The Hidden Oases: Unveiling Trophic Dynamics in Namib's Fog Plant Ecosystem

The Hidden Oases: Unveiling Trophic Dynamics in Namib's Fog Plant Ecosystem | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article The Hidden Oases: Unveiling Trophic Dynamics in Namib's Fog Plant Ecosystem Huei Ying Gan, Karin Hohberg, Clément Schneider, Martin Ebner, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3496857/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Jun, 2024 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract The Namib Desert is a hyperarid coastal desert where fog is a major moisture source. We hypothesized that the fog-harvesting grass Stipagrostis sabulicola establishes an important ecological niche in the extreme Namib Sand Sea ecosystem, referred to as "Fog-Plant-Oases (FPO)". Using a combination of extraction methods, we collected and described the above- and belowground FPO invertebrate communities and inferred their trophic feedings based on stable carbon and nitrogen isotope values. Our findings revealed a complex trophic structure and a unique food web, all of which revolve around a single fog plant as the primary producer. We demonstrated that S. sabulicola serves as the primary energy source for the aboveground food web, encompassing a diverse range of trophic levels. Nevertheless, the distinctive stable isotope values of bacterial- and fungal-feeding nematodes indicated the separation of the aboveground niche, which is primarily sustained by S. sabulicola, from the belowground niche, where wind-blown sediments serve as the main energy source. These findings further accentuate the role of S. sabulicola not only as a primary producer but also as a source of moisture and habitat provider for belowground invertebrates. Huei Ying Gan, Karin Hohberg, and Clément Schneider contributed equally to this work. Earth and environmental sciences/Biogeochemistry Earth and environmental sciences/Climate sciences Earth and environmental sciences/Ecology Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Hydrology Figures Figure 1 Figure 2 Figure 3 Introduction Fog oases are fertile vegetation islands that rely on fog condensation for their water supply. They have been widely studied in the lomas formation in Peru and Chile (Peru & Péfaur, 1982; Pinto et al., 2006; Rundel & Dillon, 1998), in the relic forests Fray Jorge (30°S) at the top of the coastal range (400 – 650 m ASL) in Chile (Gonzales et al., 2023), the redwood forest Sequoia sempervirens in northern California (Dawson, 1998) and the cloud forests of the central South Arabian mountains of Yemen and Oman (Ball & Tzanopoulos, 2020). In the present study, we investigated “Fog-Plant-Oases” (FPOs), which operate on a significantly smaller scale and revolve around individual plants compared to previously studied fog oases that function at the community or ecosystem level. Beneath single grass tussocks of a fog-harvesting plant, soil hammocks or biogenic hillocks were formed, creating isolated islands with moisture and food availability (Danin, 1991). The formation of soil hammocks is postulated to create stable conditions that encourage the utilization and colonization of such FPOs by other species as well as support the growth of the plant itself. Nonetheless, the function of FPOs, particularly by the fog-harvesting specialist Stipagrostis sabulicola ( Poaceae ) (Ebner et al., 2011), as trophic hotspots for above- and belowground invertebrates have not been examined. The Namib Desert is a hyperarid coastal desert in which fog precipitation serves as a significant moisture source (Frossard et al., 2015; Henschel & Seely, 2008; Lancaster & Seely, 1984). At our study area in the Namib Sand Sea, near Gobabeb (23°34’S 15°02’E), fog from the Atlantic Ocean is a more regular moisture source (39 mm mean annual condensation) than rainfall (21.2 mm mean annual precipitation) (Henschel, 2000). Advection fog condensation, where the moisture is derived from evaporation over the South Atlantic Ocean and transported inland by onshore winds, is mainly influenced by the distance from the coast and elevation (Mitchell et al., 2020). To cope with the extreme dryness, a considerable number of endemic species of the flora and fauna of Namib have adapted to exploit atmospheric moisture (Mitchell et al., 2020). An excellent example of how organisms adapted to extreme aridity in the Namib Desert and even shaped their environment is the formation of FPOs by the perennial endemic grass S. sabulicola . As shown previously, S. sabulicola possesses specialized leaf structures that are highly effective at condensing moisture from the air (Ebner et al., 2011; Roth-Nebelsick et al., 2012). Belowground, S. sabulicola has a shallow but extensive root system for effective anchoring in the unstable and highly dynamic windblown sand and uptake of moisture condensing on the sand surface (Louw & Seely, 1980). Overall, these studies have shown the distinctive morphological characteristics that enable S. sabulicola to utilize fog water efficiently and stabilize Aeolian sand. The trophic structure in an ecosystem depicts its energy and nutrient transfers, commonly studied and illustrated through its food web (Holt & Loreau, 2002). Despite their major importance in global biogeochemical cycling, the above- and belowground food webs of ecosystems are still poorly understood, mainly due to the huge diversity of soil-dwelling and aboveground organisms of which many are general feeders (Crotty et al., 2014; Potapov et al., 2019; Scheu, 2002). This is exacerbated by the fact that food web studies are focused on certain land uses and climate regions, such as agricultural lands and temperate ecosystems (Crotty et al., 2014; Potapov et al., 2019; Scheu, 2002). Therefore, there remains a need to continue exploring the trophic structure of both soil-dwelling and aboveground animal communities, particularly in arid and hyperarid ecosystems as they cover a high proportion of the Earth’s surface and due to their sensitivity to climate change (Nielsen & Ball, 2015; Quoreshi et al., 2022; Whitford W. G., 1996). Previously, only a couple of studies employed stable isotope analysis in understanding the belowground food web in a hyperarid desert, including the investigation of the diet of soil nematodes and tardigrades under biological soil crusts in the arid Southwest of US (Darby & Neher, 2012) and the study of the diet of nematodes, tardigrades, rotifers, and microarthropods in the McMurdo Dry Valleys in Antarctica (Shaw et al., 2018). Our study presents the community composition and abundance of previously unexplored above- and belowground invertebrates found around the S. sabulicola FPOs. We hypothesized that the fog-harvesting efficiency of S. sabulicola facilitates important ecological niches within the Namib Sand Dune ecosystem. Additionally, we proposed that the plant litter from S. sabulicola serves as the primary carbon source for the FPO trophic structure, which fuels carbon flow from lower to higher trophic levels. To test these hypotheses, we aimed to measure the natural variations of δ13C and δ15N of above- and belowground invertebrates of the S. sabulicola FPOs, and to evaluate its trophic connections and food web. Isotopic analysis is based on the premise that the stable carbon and nitrogen isotopes (δ 13 C and δ 15 N) of above- and belowground invertebrates reflect their diet compositions. This can be used to determine their trophic positions i.e., detritivores, secondary decomposers, herbivores, or predators within the soil web (Ponsard & Arditi, 2000; Vanderklift & Ponsard, 2003). Combined with isotope mixing models, a finer resolution of their diet compositions can be achieved (Govan et al., 2023; Parnell et al., 2013; Post, 2002). In addition, due to the lack of rainfall that activates microbial decompositions in this hyperarid ecosystem (K. Jacobson et al., 2015; K. M. Jacobson & Jacobson, 1998), we further aimed to identify the main primary decomposers of the S. sabulicola FPOs by estimating the contributions of plant litter in their diets. Results Diversity and abundance of FPO fauna Aboveground fauna The overall composition of non-flying or poor flying arthropods were evaluated by bush-beating. Rapid flyers such as Diptera and Hymenoptera often escaped and thus were mostly not studied. Collected arthropods included: oribatid mites ( Zygoribatula sp., 100 specimens), beetles ( Cybocephalus sp., 17 specimens, Exochmus flaviventris , 1 specimen), thrips ( Haplothrips sp . , 15 specimens), barklice ( Liposcelis sp., 14 specimens), weevils ( Sibinia sp . , 13 specimens), pseudoscorpions ( Nanolpium sp ., 9 specimens), leafhoppers ( Deltocephalinae sp . , 5 specimens), jumping spiders ( Salticinae sp . , 2 specimens), ground sac spiders ( Thysanina sp . , 1 specimen), and parasitoid wasps ( Haltichellinae sp . , 2 specimens). Peeling of plant stems revealed the occurrence of armoured scale insects (Diaspididae) and mealybugs ( Pseudococcidae sp . ) and again the oribatid mite Zygoribatula sp . , under the leaf sheath near the nodes. Details on the taxonomic assignment of these species are provided in Appendix 1. Further groups observed on the leaves of S. sabulicola , but not studied in detail, included red velvet mites (Trombidiidae), predatory mites (Gamasina), and more insects: cockroaches (Blattodea, 1 specimen), grasshoppers (Orthoptera, 1 specimen), true bugs (Heteroptera, 1 specimen), flies (Diptera, several spp.) and parasitoid wasps (Hymenoptera, several spp.). Supplementary collection of dune surface dwellers that frequently visit S. sabulicola included dune ants ( Campotonous detritus ), which tends scale insects and leafhoppers to collect honeydew (Curtis, 1985b). These ants are more abundant on the base dunes as well as on the dune slope as compared to the high dunes. Ten individuals of tenebrionid beetles consisting of Onymacris plana (4 specimens), Physadesmia globosa (3 specimens), and Onymacris laeviceps (3 specimens) were collected both from the high dunes as well as from the dune base near the Kuiseb Riverbed. As a comparison to the S. sabulicola food web, two individuals of blister beetles Hycleus zigzagus were included, which were the herbivores of the !Nara melon ( Acanthosicyos horridus ) that also occurs on the base of the dunes. A. horridus is a perennial endemic shrub and another potential fog-harvesting FPO that grows alongside S. sabulicola at the base of Namib dunes. Belowground fauna A total of 5233 nematode individuals with a total biomass of 913.4 µg biomass (fresh weight) were extracted through wet extractions (Baermann method). Most individuals were found in soils (dune sands) under mature FPOs with the highest density in deeper soil layers (30-50 cm depth). The nematodes were predominantly bacterial feeders (84.8% of overall biomass) represented by the genera Acrobeles, Cephalobus, Cervidellus, Chiloplacus, Elaphonema, Panagrobelus, Panagrolaimus, Zeldia , and some juvenile Mesorhabditidae and Diplogastridae . Fungal-feeding nematodes contributed to 14.7% of overall nematode biomass and consisted of Aphelenchoides, Aphelenchus, Ditylenchus, Paraphelenchus , and a few Tylenchidae . As a third feeding group, omnivorous nematodes were detected only sporadically, but due to their large body size still accounted for 0.5% of overall nematode biomass. Tardigrades were extracted from only 3 of the 84 soil samples. They belonged to the genus Hexapodibius and were found with 3, 5, and 5 specimens under matured FPOs at 5-10 cm soil depth. Also, some mites (Pediculochelidae sp.) were found in very low numbers. Dry extractions (Berlese method) of another subset of 84 soil samples did not yield any animals, and only small amounts of nematodes, which were not analysed, were caught in underground pitfalls. Flotation (84 samples) yielded altogether 121 mites (Micropasmmidae sp., Pediculochelidae sp., and some Astigmata (not further analysed)) and the remains of a single springtail (cuticle of an Entomobryidae ). Stable isotope values δ 13 C and δ 15 N values of basal resources The average δ 13 C values of different parts of S. sabulicola spanned only 1.4‰ between -13.7 and -15.1‰ (Table 1). The fresh leaves were 13 C-depleted (δ 13 C = -15.1±0.7‰) compared to dead leaves (δ 13 C = -14.0±0.6‰) and dead leaves with visible fungal colonization (δ 13 C = -14.0±0.5‰). Belowground, plant roots had isotopic values of δ 13 C = -14.1±0.3‰, and rhizosheaths δ 13 C = -13.7±0.4‰. Soil detritus (light fraction organic matter) extracted from hummocks of mature FPOs had δ 13 C = -14.3±0.2‰ values. The average δ 15 N values of different parts of S. sabulicola spanned almost 4‰ between -1.9‰ and 2.0‰. The δ 15 N of fresh leaves were close to the atmospheric δ 15 N value of δ 15 N = 0.2±1.5‰. Dead leaves (δ 15 N = -1.9±1.6‰) and dead leaves with visible fungal colonies (δ 15 N = -0.7±2.5‰) were 15 N-depleted when compared to fresh leaves. Belowground, plant root (δ 15 N = 0.1±1.4‰) and rhizosheath (δ 15 N = 0.8±0.4‰) were 15 N-enriched in comparison to fresh leaves; while dead leaves with soil detritus (δ 15 N = 2.0±1.2‰) were enriched in δ 15 N values compared toplant samples. Compared to S. sabulicola , which had δ 13 C values typical of C 4 plants, the δ 13 C values of A. horridus litter resembled those of typical C 3 plants (δ 13 C = -21.7±0.8‰). Soil detritus under A. horridus (δ 13 C = -17.1±1.2‰) were markedly 13 C-depleted compared to the dead leaves and soil detritus of S. sabulicola . Compared to the litter and detritus of S. sabulicola , the plant litter (dead stem) of A. horridus (δ 15 N = 4.2±1.6‰) and soil detritus under A. horridus (δ 15 N = 3.7±0.2‰) were 15 N-enriched. δ 13 C and δ 15 N values of invertebrates A subset of the above-mentioned above- and belowground invertebrates were included in the stable isotope analysis for the construction of FPO trophic structure (Figure 1). Aboveground, invertebrates that have δ 13 C values close to the dead leaves of S. sabulicola (δ 13 C = -14.0±0.6‰) include the saprophilous and fungivorous Zygoribatula sp . (δ 13 C = -14.7±0.7‰), sap feeders Deltocephalinae sp. (δ 13 C = -13.9±0.4‰) and Diapsididae sp . (δ 13 C = -15.7±0.8‰). Saprophilous and fungivorous Liposcelis sp . was markedly 13 C-depleted (δ 13 C = -20.6±3.3‰) compared to the fresh leaves of S. sabulicola (δ 13 C = -15.1±0.7‰). Similarly, the herbivores Sibinia sp . (δ 13 C = -21.0±1.6‰) and Haplothrips sp. (δ 13 C = -17.8±1.9‰) were 13 C-depleted compared to the fresh leaves of S. sabulicola . Dune surface dwellers were also 13 C-depleted compared to the dead leaves of S. sabulicola including C. detritus : δ 13 C = -15.8±1.8‰ , O. laeviceps : δ 13 C = -16.0±1.5‰ , and O. plana : δ 13 C = -17.2±2.0‰ , while the δ 13 C values of P. globosa were markedly depleted (δ 13 C = -25.2±0.6‰) compared to the tenebrionid beetles from the genus Onymacris . Predators Salticinae sp . (δ 13 C = -14.1±0.3‰) and parasitoids Haltichellinae sp. (δ 13 C = -14.0±0.3‰) had δ 13 C values almost identical to the dead leaves of S. sabulicola (δ 13 C = -14.0±0.6‰). Scale insects predator Cybocephalus sp . (δ 13 C = -13.5±0.2‰) and predator Thysanina sp . (δ 13 C = -12.8‰) was 0.5-1.2 ‰ 13 C-enriched compared to the same plant material. In contrast, the δ 13 C value of Nanolpium sp . (δ 13 C = -18.4±2.5‰) was markedly 13 C-depleted compared to the dead leaves of S. sabulicola as well as other predatory species. The summary of aboveground invertebrates, their expected trophic feeding types, and isotopic values are summarised in Table 2. Belowground, both bacterial- (δ 13 C = -24.6±1.9‰) and fungal-feeding nematodes (δ 13 C = -23.6±0.2‰) were markedly 13 C-depleted compared to dead leaves of S. sabulicola . Values of δ 15 N in a consumer’s tissue are more 15 N-enriched compared to those of its diet, and this is termed “enrichment” as denoted by ∆, where ∆ 15 N = δ 15 N consumer - δ 15 N diet (Eq. 1). In the present study, ∆ 15 N values were used to calculate trophic positions (TP) of above- and belowground invertebrates at the S. sabulicola FPOs, where dead leaves of the fog plant were assumed to form the trophic base (∆ 15 N = 0) of the invertebrate food web. Calculation of trophic positions assumes the enrichment factor per trophic level equals 3.4‰ according to a previous large-scale study on marine and freshwater organisms by Minagawa & Wada (1984). Therefore, Eq. 1 is rewritten as TP = [δ 15 N invertebrate - δ 15 N baseline ] / 3.4, where δ 15 N invertebrate = δ 15 N values of above- and belowground invertebrates found on or within proximity to S. sabulicola , and δ 15 N baseline = dead leaves of S. sabulicola . Likewise, the δ 15 N baseline to calculate the trophic position of H. zigzagus , the herbivore species found feeding on A. horridus , was assumed to be the δ 15 N values of dead A. horridus stem. Overall, the gradient spanned over 16 δ units in ∆ 15 N values for all FPO invertebrates that occupied 5 trophic positions. The first trophic position was occupied by primary decomposers including Zygoribatula sp. (∆ 15 N = 0.05±0.6‰) and Liposcelis sp. (∆ 15 N = 2.8±1.9‰) as well as sap feeder Diapsididae sp. (∆ 15 N = 0.9±0.6‰). The second trophic level was occupied by the most taxa with various feeding strategies, including sap feeder Deltocephalinae sp. (∆ 15 N = 3.2±1.2‰), predators Thysanina sp. (∆ 15 N = 4.0‰) , Nanolpium sp. (∆ 15 N = 5.5±0.7‰) , and Cybocephalus sp. (∆ 15 N = 5.9±2.8‰) , bacterial-feeding nematodes (∆ 15 N = 5.4±1.2‰), as well as herbivore H. zigzagus (∆ 15 N = 6.2±1.1‰), and honeydew feeder C. detritus (∆ 15 N = 6.6±0.9‰) . Both tenebrionid species occupied the third trophic level: O. laeviceps (∆ 15 N = 6.7±5.0‰) and O. plana (∆ 15 N = 7.2±1.8‰). P. globosa is excluded from trophic level calculation because of their distinctive δ 13 C values and lack of a suitable baseline value. The fourth trophic level was occupied by Salticinae sp. (∆ 15 N = 10.9±0.9‰) and Haplothrips sp. (∆ 15 N = 11.4±2.5‰) , while Sibinia sp. (∆ 15 N = 13.7±1.4‰) and Haltichellinae sp. (∆ 15 N = 16.7±0.4‰) occupied the fifth trophic level. Fungal-feeding nematodes were positioned way below the trophic baseline due to their markedly low ∆ 15 N value (-11.04 ± 3.90‰). Diet estimates of FPO invertebrates Estimates for the diet of aboveground invertebrates were conducted using the Stable Isotope Mixing Models (function “simmr”) (Govan et al., 2023). The analyses were based on both the δ 13 C and δ 15 N values of consumers (mixtures) as well as their potential diets (sources). Corrections were considered for the analyses, which included the standard deviations for consumers’ δ 13 C and δ 15 N values, the % of carbon and nitrogen of diet, as well as enrichment factors for 13 C=0.4±1.3‰ and 15 N=3.4±1.0‰ according to Post (2002). Mixing models were used to estimate i) the contributions of dead leaf, soil detritus, and scale insects ( Diaspididae sp.) to the diet of primary as well as secondary decomposers and ii) the contributions of lower ranked invertebrates to the diet of predatory taxa. Estimations of potential dietary components of the sampled invertebrates varied markedly as indicated by high standard deviations (Table 3 and Table 4). Nevertheless, the estimates suggested that fungal-infected dead leaves of S. sabulicola constituted a large proportion in the diet of Zygoribatula sp. (78±27%) and Cybocephalus sp. (67±17%). Soft scales Diaspididae sp. had substantial contributions to the diets of Liposcelis sp. (73±42%), O. laeviceps (78±19%), and O. plana (89±5%). Soil detritus which comprised of light fraction organic matter under S. sabulicola FPOs showed an important contribution to the diet of C. detritus (86±18%). Among predatory taxa that occupy lower trophic levels (TL), Liposcelis sp. contributed 65±10% to the diet of Nanolpium sp. (TL= 2) while Zygoribatula sp. contributed 46±31% to the diet of Thysanina sp. (TL= 2). Among the “higher” predatory taxa, Cybocephalus sp. contributed 37±17% to the diet of Salticinae sp. (TL= 4) while Haplothrips sp. contributed 75±10% to the diet of Haltichellinae sp. (TL = 5). The summary of the trophic relationships was shown in Figure 3. Discussion The ability of S. sabulicola to establish itself in barren environments from the seedling stage classifies it as a pioneer species. However, unlike most pioneer species which were eventually replaced by other successional species once stable conditions are achieved, S. sabulicola continues to grow into large grass tussocks with hummock formations and ultimately become the climax species. The persistence of S. sabulicola as the only plant species on the higher dunes can be attributed to two main mechanisms. Firstly, the fog plant possesses distinctive morphology that enables it to harvest fog and exploit near-surface moisture effectively, as well as to anchor itself on the highly unstable sand dunes (Ebner et al., 2011; Louw & Seely, 1980; Roth-Nebelsick et al., 2012). Secondly, abiotic factors such as the rapid sand movement on the dunes and scarce rainfall hinder the succession of the fog and dune specialists by other plant species (Yeaton, 1988). Overall, the unusual formation of S. sabulicola FPOs highlights their potential as habitats for various invertebrates and a unique food web. In this study, we illustrated that S. sabulicola FPOs harbor trophic niches for a diverse array of above- and belowground invertebrates. Aboveground through bush-beating, we found a total of 12 arthropod taxa on the leaf surface and within the leaf sheaths, with an additional 7 taxa observed, but not studied in detail. In contrast, flotation of soil samples yielded only a few soil microarthropod species which were predominantly mites. Belowground microarthropods under S. sabulicola hummock were previously recognized by Coineau & Seely (1983). They retrieved a higher diversity of taxa than us, especially with the findings of Arthropleona springtails (a single cuticle found by us). Their sampling methodology differed from ours, as they frequently watered a well in the sand for one week before sampling 10 L of sands. Our sampling design was likely not sensitive enough to capture the rare taxa (Pauropoda). From the cuticle we found, we suspect the reported Arthropleona to belong to a rather common, yet undescribed, Entomobryidae we observed in the Kuiseb and in Gobabeb. The species is a rapid runner that could have rapidly aggregated in the watered well while being scarce in the natural conditions targeted by our sampling. Though bush-beating and soil sampling are difficult to compare, arthropod species richness and biomass were evidently higher on the grass canopy of S. sabulicola than in the sand near the roots, revealing the complexity of these “hidden oases”. Soil life is probably inhibited by the instability of the dune surface (Scholz, 1972), but the presence of a thriving fauna community on the aboveground canopy was undeniably enabled by an ample supply of fog water stored in the grooved stems of S. sabulicola (Ebner et al., 2011). Sufficient wetting of aboveground litter has also been previously observed to undergo rapid fungal decomposition which additionally provides aboveground fauna with high-quality litter (K. Jacobson et al., 2015). Overall, the presence of moisture, food sources, and potential wind and solar protection provided by the grass tussock canopy collectively render it a suitable habitat for the discovered invertebrates. Among the aboveground soil invertebrates that have similar δ 13 C values as S. sabulicola , their trophic levels were observed to span from the detritivore ( Zygoribatula sp . ) to the predatory taxa ( Cybocephalus sp. to Salticinae sp. , and Haltichellinae sp.). This points to S. sabulicola as the primary source of carbon that fuelled the aboveground FPO food web from the bottom to the higher trophic levels (Figure 2, Figure 3). However, the δ 13 C values of the other half of the FPO invertebrates were found to be 13 C-depleted, some markedly, compared to the litter of S. sabulicola . For instance, Liposcelis sp . was about 6‰ depleted compared to the litter of S. sabulicola . However, it is not clear if the markedly depleted δ 13 C values of this saprophilous and fungivorous species mirrored the plant sap of S. Sabulicola , since δ 13 C values of phloem sap have been previously reported to be like plant leaves (Sagers & Goggin, 2007). Depleted δ 13 C values compared to S. sabulicola were also apparent in Haplothrips sp. and Sibinia sp., both typically classified as plant herbivores. Moreover, the phenomenon of markedly depleted δ 13 C values among plant herbivores seemed to occur only within the FPO soil food web, whereas H. zigzagus , the arthropod that fed on the stem of A. horridus , showed a 3‰ enrichment in δ 13 C compared to its host plant. As mentioned above, the markedly depleted δ 13 C values of some of the plant herbivores of the FPOs differed from earlier studies that reported a trend of increasing δ 13 C values moving up the trophic level (Ponsard & Arditi, 2000; Scheu & Falca, 2000). Past research has reported variations in δ 13 C values of different primary and secondary photosynthetic products from various temperate plants e.g. 13 C-enriched sucrose and starch and 13 C-depleted lignin and lipid (Gleixner et al., 1993). Therefore, these herbivore species yet with distinct δ 13 C values compared to their host plant may be feeding on specific types of photosynthetic products with depleted δ 13 C values than the bulk leaves or litter of S. sabulicola . Apart from diet, the lower δ 13 C values could also be explained by higher lipid content in animal tissues, which is generally more 13 C-depleted compared to proteins and carbohydrates. The depleted δ 13 C values due to higher lipid content are shown by negative correlations between invertebrate C/N ratios and their δ 13 C values (Focken & Becker, 1998; Post et al., 2007). Overall, we found significant negative correlations between the δ 13 C values of Liposcelis sp . and their C/N ratios (adjusted R-squared = 0.93, p-value = <0.001) which supports this hypothesis, but no correlation between δ 13 C values and C/N ratios were found for Haplothrips sp. and Sibinia sp. Additionally, we discovered that the FPO invertebrates showed a pattern of lower C/N ratios (Table 2) compared to soil invertebrates from temperate forests and grasslands (Crotty et al., 2014; Ponsard & Arditi, 2000). This finding suggests that climatic influence, in this case hyperaridity, may be driving these differences. This hypothesis is supported by prior studies which demonstrated that lipid storage plasticity is associated with starvation tolerance in arthropods under temperature manipulations (Jensen et al., 2018; van Dooremalen & Ellers, 2010). Given the importance of detritivores in the decomposition of plant litter outside of rain events in the Namib Desert (K. Jacobson et al., 2015; K. M. Jacobson & Jacobson, 1998), we further focused on the diet of detritivore species at FPOs. In the present study, we found oribatid mites from the genus Zygoribatula sp. to be the most abundant primary decomposer species inhabiting the leaves of S. sabulicola. Previous studies have reported that oribatid mites from the same genus, Zygoribatula exilis, exclusively occupy trees or lichens (Fischer et al., 2010). Isotope data from prior studies on Z. exilis in temperate forests indicated a slight 15 N-enrichment relative to the tree barks, implying that they feed on algae and bryophyte (Erdmann et al., 2007). Similarly, our diet estimates showed a majority contribution of dead leaves with heavy fungal infection to the diets of Zygoribatula sp., thus highlighting their importance as the main primary decomposer of the S. sabulicola FPOs and potentially helping to control fungal pathogens of the fog plant. We further investigated the roles of tenebrionid beetles and dune ants as potentially important detritivores of the S. sabulicola FPOs. Our stable isotope data confirmed the niche separation between P. globosa and other tenebrionid beetles from the genus Onymacris (Figure 2). In agreement with previous studies, we showed that specimens from the genus Onymacris tend to inhabit open sand and vegetation-less dune slips compared to P. globosa which occupies the dry riverbeds and the gravel plains (Osberg et al., 1986; Roberts et al., 1991). In terms of diets, our estimates showed that the leaf litter of S. sabulicola did not have significant contributions as food resources for O. laeviceps and O. plana . Furthermore, the tenebrionid beetles also occupy a rather high trophic level like other predators. Previously, wind-blown litter has been suggested to dominate the diet of these species (Holm & Edney, 1973), but our stable isotope data provide evidence that plant litter plays a less important role in their diets compared to other food sources with higher δ 15 N values, such as a diet rich in animal-derived sources. The dune ants C. detritus , while proficient at clearing surface detritus, do not function as detritus consumers themselves (Curtis, 1985a). Instead, they primarily subsist on a diet of honeydews, which are secreted by aphids and scale insects (Curtis, 1985b). In line with this, we observed that the δ 13 C values of C. detritus closely mirrored those of the Diaspididae sp. that were notably abundant within the inner sheath of S. sabulicola . However, diet estimates also showed a high contribution of soil detritus in the diet of C. detritus , confirming the large diet spectrum of this generalist feeder. In summary, these results indicate that O. laeviceps, O. plana , and C. detritus were not the main consumers of S. sabulicola 's litter , and likely played a smaller role than Zygoribatula sp. in the decomposition of plant litter within the FPOs. Belowground, soil nematodes were predominantly bacterial feeders (bacterivores) followed by fungal feeders (fungivores), which mirrors their trophic composition of the well-studied gravel plains nearby and other arid ecosystems (Marais et al., 2020; Pen-Mouratov et al., 2004; Steinberger Y. et al., 1988; Treonis et al., 2022). Overall, the markedly depleted δ 13 C values of both trophic groups of nematodes compared to the litter of S. sabulicola suggest that the fog plant might not be their main carbon source. Compared to the δ 13 C values of aboveground invertebrates which in general resemble δ 13 C values of S. Sabulicola , the δ 13 C values of belowground fauna indicate that their main energy source originated from wind-blown sediments. The distinct energy sources between the above- and the belowground food web suggest two separate niches. According to their 15 N-enrichment (∆ 15 N), bacterivores occupied the second trophic level of the FPO food web, confirming their trophic roles as secondary decomposers (Kudrin et al., 2015; Melody et al., 2016). Markedly depleted ∆ 15 N values, however, positioned the fungivorous nematodes way below the baseline of the S. sabulicula plant tissues, showing similar values as lichen-feeding oribatid mites in a temperate forest (Erdmann et al., 2007). To the best of our knowledge, there is no other in-situ comparison of δ 15 N values among fungal-feeding nematodes in the current literature. Results from a feeding experiment conducted by Ruess et al. (2004) showed that the depleted ∆ 15 N of fungivores Aphelenchoides saprophilus originated from its fungal food source that was depleted in ∆ 15 N compared to the medium where the fungi grew. Together with these previous findings, our results indicate that depleted ∆ 15 N of fungivores may be related to feeding on low-quality food sources such as blown-in detritus, lichens, or fungal biomass which is typically N-depleted (Mouginot et al., 2014), as well as mechanisms of 15 N fractionations by nematode to compensate for low-quality food resources. Methods Site description The study was conducted in the Namib Sand Sea near the Gobabeb Namib Research Institute (23°34’S, 15°03’ E, 407m a.s.l., ~1km south across the Kuiseb River). S. sabulicola is the dominant plant species growing on the Aeolian dunes, particularly the plinth (flattened slope on the dune base) and the windward slopes (Robinsonj & Seely, 1980; Southgate et al., 1996). At the dune base, S. sabulicola was found to coexist with other Stipagrostis species, Acanthosicyos horridus (!Nara melon) and Cladoraphis spinosa . A total of seven FPOs established by S. sabulicola with two contrasting grass tussock sizes (3 young and 7 mature tussocks with signs of senescence) were selected as study sites. Mature and young FPOs referred to growth stages of S. sabulicola that forms the FPO. At mature FPOs, sizable sand hummocks (up to 10m x 9m wide) were formed by tussocks that frequently grow up to 2 meters tall, while young plants (under 1 meter in height) did not accumulate visible hummocks yet. Open sand next to the FPOs were assigned as controls. All three young FPOs and two mature FPOs were located on dune ridges, while two mature FPOs were located on the windward plinth and dune base respectively. Sampling and processing of samples Field work and sampling of all study materials were carried out during the fog season in early September 2022. Samples for extracting soil nematodes and other belowground invertebrates consisted of two replicates (one for wet extractions for nematodes and one for other fauna) of 3-4 soil cores each per FPO (diameter 5cm, height 5cm), with 84 samples in total. Immediately after sampling, nematodes were extracted from soil samples using a modified Baermann method (wet extraction) for 48 hours. In this study, we used "soil" as a generic term for "ground substrate", which in this case refers to sandy substrate from the dunes. At the end of the extraction, nematodes were heat-killed and fixed with formaldehyde. The nematodes were identified to genus level, and where possible to species, under an inverted microscope (400x magnification). The body length and width of each specimen was measured and translated into body mass using the formula of Andrassý (1956). Nematode genera were assigned to bacterivorous, fungivorous, and omnivorous feeding types following Yeates et al. (1993). Several adults from each genus were isolated for preparation on permanent slides and species determination. The remaining bacterivores yielded sufficient biomass for isotope analysis, hence were hand picked under the inverted microscope in two samples, which weighed 48.5 and 105.8 µg dried nematode mass, respectively. The numbers and biomass of fungivorous nematodes did not suffice, thus two samples containing both bacterivores and fungivores were weighed together. Since in both of these pooled samples, the biomass ratios of the two trophic groups (m bac and m fun ) were accurately measured, and the isotopic signal for bacterivores (F bac ) was already determined, the isotope signals (F fun ) could be calculated from the isotopic signal F pool and biomass m pool of the pooled samples, using a two pools mass-balance equation: m pool F pool = m bac F bac + m fun F fun , where m = the biomass ratios and F = the fractional isotopic abundance of bacterivorous and fungivorous nematodes within the two pooled samples. Other soil arthropods were extracted using a combination of Berlese-Tullgren (dry extraction), underground pitfalls, and flotation methods. Bush-beating was used to sample the small invertebrates living on the plant, while macrofauna (ants and darkling beetles) were collected on sight by hand. Stems of the plant were also peeled under the stereomicroscope to recover small invertebrates living under the leaf layers. All fauna except for nematodes were killed and preserved in 100% ethanol solution. Preservation of faunas in ethanol and formalin can affect their isotopic values but the shift in values was usually less than 1‰ (Fábián, 1997; Krab et al., 2012; Sticht et al., 2006). Plant materials (fresh leaves, dead leaves, plant roots, and rhizosheath) were dried at 60°C for 3-5 days. Soil detritus was extracted using a flotation method (3:1 water:soil ratios) then filtered through a fine mesh (6 µm). Above ground invertebrates were collected by beating the stems and leaves of the grass into a plastic box, then captured with a mouth aspirator modified for immediate preservation in 100% ethanol. We collected most arthropods that did not fly away immediately. We sorted the animals into morphospecies using a stereo-microscope. We selected the morphospecies we estimated to offer enough biomass for stable isotopes analysis and molecular sequencing. One individual of each was selected for genome skimming, either from a cutted leg, or from the whole individual depending on the size. DNA extractions were done using the DNeasy Blood & Tissue Kit (Qiagen, Hilden), Illumina libraries were made using the NEBNext® Ultra™ II DNA Library Prep Kit (New England Biolabs, Ipswich), for a 150 bp insert size. Sequencing was done at Novogene UK on a NovaSeq 6000 system (Illumina, San Diego), aiming for 10Gb per library. The sequenced libraries were trimmed with Trimmomatic (v0.39) (Bolger et al., 2014) then assembled with SPAdes (v3.14.1)(Bankevich et al., 2012). The COI-5P marker (658 bp) and the 28S rDNA full gene was searched directly in the scaffolds using Blastn (v2.13.0+). The integrity of the protein coding sequences was verified, and each sequence was first queried on Genbank to check for obvious contaminants. We further confirmed that none of the sequences could be directly assigned to a species using the BOLD identification tool. We then proceeded to a phylogenetic placement. We adapted our method case by case, but the general approach was as follows. For each morphospecies, we subselected the BOLD public database using the lowest taxonomic group we recognized (Araneae, Cicadellidae, Coccoidea, Cucujoidea, Hymenoptera, Psocodea, Pseudoscorpionides and Thysanoptera). For each supra-family taxa selection, we sampled the database allowing from 20 to 50 records for each family (duplicated sequences removed, records randomly selected, and number of maximum records manually tuned to keep the number of OTUs around or below 3000). A rapid phylogenetic placement was performed using MAGUS (Smirnov & Warnow, 2021) for multiple sequence alignments and FastTree2 (Price et al., 2010) for ML tree inference. When the dataset contained less than 400 OTUs, we used Muscle v5 (Edgar, 2022) + Raxml-ng (Kozlov et al., 2019) instead. The trees were visualised using iTOL (Letunic & Bork, 2021). The closest family was selected as a novel filter of the BOLD database, and the sampling process was repeated at genus level. For some taxa, COI-5P did not allow a taxonomic placement. In such cases we retrieved suitable comprehensive phylogenetic datasets based on 28S rDNA and used them to accurately confirm the family of the concerned species. Then again, high resolution placement was done using the COI-5P against the BOLD public database. Once the closest genus could be identified, we searched the literature for previous reports in Namibia. Details for each species are provided in Appendix 1. Stable isotope analysis and statistics Prior to weighing, all plant and detritus samples were hand-milled manually using a pestle and mortar to ensure homogeneity and transferred into tin capsules. Invertebrates were transferred directly in tin capsules and oven-dried at 60°C for at least 24 hours. Nematodes were weighed in tin capsules with lids to avoid biomass loss from evaporation. Bigger arthropods (tenebrionid and blister beetles) were freeze-dried (Heto PowerDry LL3000; Thermo Fisher Scientific, Waltham, USA) for 48-72 hours. C/N concentrations and stable isotopes were quantified using an elemental analyzer coupled to isotope-ratio mass spectrometer (IRMS) (MAT 251, Finnigan, Bremen, Germany) (Langel & Dyckmans, 2014). Isotope ratios of all samples were reported in conventional δ-notation: , where R is the ratio of heavier to lighter isotope. The δ values were expressed as per mill (‰) or parts per thousand. All statistical analyses were conducted in R version 3.3.2 (R Core Team, 2020). The R package Stable Isotope Mixing Models (function “simmr”) was used for the reconstruction of faunal diet (Govan et al., 2023). The mixing models required both the δ 13 C and δ 15 N values of consumers as well as likely sources (diet) including corrections (i.e. standard deviations for δ 13 C and δ 15 N values, enrichment factor for 13 C=0.4±1.3‰ and 15 N=3.4±1.0‰ according to, as well as the % of carbon and nitrogen in diet). Simmr was used to estimate: 1) the contributions of dead leaf, soil detritus, and scale insects to the diets of detritivore species and ii) the contributions of invertebrates from lower trophic levels to the diet of predatory species. Fitting linear models (function “lm”) was used to determine the correlation between δ 13 C of invertebrates and their C/N ratios. Plant Collection Statement The plant collection and use were in accordance with all the relevant guidelines provided by the Namibian National Commission on Research, Science, and Technology, as stipulated on the research permit issued with Permit Number RPIV00672022. 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Values are reported as mean ±SD. samples n Total carbon (%) Total nitrogen (%) C/N ratio δ 13 C δ 15 N Stipagrostis sabulicola Fresh leaves 5 45.5±1.3 1.4±0.3 34.9±10.4 -15.1±0.7 0.2±1.5 Dead leaves 7 43.0±3.0 0.5±0.1 88.5±20.4 -14.0±0.6 -1.9±1.6 Dead leaves with fungal infection 12 43.8±2.3 0.9±0.5 57.0±23.1 -14.0±0.5 -0.7±2.5 Root 6 45.8±0.5 0.6±0.1 71.8±10.1 -14.1±0.3 0.1±1.4 Rhizosheath 8 20.4±6.7 0.5±0.2 43.5±5.6 -13.7±0.4 0.8±0.4 Soil detritus 7 34.5±9.8 0.9±0.2 38.8±11.3 -14.3±0.2 2.0±1.2 Acanthosicyos horridus Litter (Dead stem) 8 43.3±3.1 1.6±0.9 38.2±27.6 -21.7±0.8 4.2±1.6 Soil detritus 6 28.8±6.6 1.1±0.2 27.5±9.3 -17.1±1.2 3.7±0.2 Table 2 . δ13C and ∆15N values found for the aboveground invertebrates of S . sabulicola FPOs. The feeding habits expected from the known biology of each group were indicated Taxon n Expected feeding habit Source δ13C ∆15N C/N Zygoribatula sp. 5 (pooled) Saprophilous, fungivorous (Erdmann et al., 2007) -14.7±0.7‰ 0.05±0.6‰ 5.2±0.3 Diapsididae sp. 5 (pooled) Sap feeder (Curtis, 1985a) -15.7±0.8‰ 0.9±0.6‰ 7.7±1.2 Liposcelis sp. 9 Saprophilous, fungivorous (Wondale Endshaw & Berhanu Hiruy, 2020) -20.6±3.3‰ 2.8±1.9‰ 9.8±4.7 Deltocephalinae sp. 3 Sap feeder (Dmitriev, 2001) -13.9±0.4‰ 3.2±1.2‰ 3.8±0.1 Thysanina sp. 1 Predator (Lyle & Haddad, 1938) -12.8‰ 4.0‰ 3.4 Nanolpium sp. 4 Predator (Judson & Heurtault, n.d.) -18.4±2.5‰ 5.5±0.7‰ 5.9±1.3 Cybocephalus sp. 4 Scale insect’s predator (Smith, 2022) -13.5±0.2‰ 5.9±2.8‰ 4.6±0.3 Camponotus detritus 6 Mainly honeydew feeder (Curtis, 1985b) -15.8±1.8 6.6±0.9‰ 4.2±0.3 Onymacris laeviceps 3 Omnivorous, mainly on plant detritus but also on green plants and dead animals (Holm & Edney, 1973) -16.0±1.5 6.7±5.0‰ 4.7±1.1 Onymacris plana 4 Omnivorous, mainly on plant detritus but also on green plants and dead animals (Holm & Edney, 1973) -17.2±2.0 7.2±1.8‰ 5.0±0.3 Physadesmia globosa 3 No specific diet, probably omnivorous (Wharton & Seely, 1982) -25.2±0.6 8.5±1.6‰ 5.3±0.7 Salticinae sp. 2 Predator (Haddad & Wesołowska, 2011) -14.1±0.3‰ 10.9±0.9‰ 3.5±0.1 Haplothrips sp. 6 Herbivorous, pollinizer (Wang et al., 2022) -17.8±1.9‰ 11.4±2.5‰ 4.9±0.6 Sibinia sp. 5 Herbivorous (Henschel et al., 2003) -21.0±1.6‰ 13.7±1.4‰ 4.7±0.1 Haltichellinae sp. 2 Carnivorous during larval development then nectar or honeydew feeder. (Heraty et al., 2013) -14.0±0.3‰ 16.7±0.4‰ 3.8±0.1 Table 3 Diet estimations of detritivores by stable isotope mixing models (mean % ±SD). Mean values above 15% are marked by bold letters C. detritus Cybocephalus sp. Liposcelis sp. O. laeviceps O. plana Zygoribatula sp. mean SD mean SD mean SD mean SD mean SD mean SD Dead leaves 0.034 0.027 0.124 0.095 0.252 0.422 0.059 0.046 0.034 0.026 0.079 0.133 Fungal-infected dead leaves 0.033 0.026 0.668 0.169 0.007 0.005 0.095 0.189 0.032 0.023 0.799 0.273 Soil detritus 0.856 0.179 0.174 0.156 0.009 0.007 0.063 0.050 0.041 0.032 0.034 0.027 Softscale insect ( Diaspididae sp.) 0.077 0.165 0.034 0.024 0.732 0.420 0.782 0.189 0.893 0.050 0.089 0.225 Table 4 Diet proportions of predators estimated by stable isotope mixing models (mean % ±SD). Mean values above 15% are marked by bold letters. Nanolpium sp. Thysanina sp. Salticinae sp. Haltichellinae sp. mean SD mean SD mean SD mean SD Liposcelis sp. 0.650 0.100 0.056 0.086 0.061 0.048 0.034 0.028 Diaspididae sp. 0.090 0.078 0.081 0.116 0.088 0.068 0.040 0.033 Deltocephalinae sp. 0.055 0.046 0.149 0.216 0.120 0.100 0.036 0.028 Zygoribatula sp. 0.119 0.085 0.464 0.307 0.078 0.058 0.033 0.025 Sibinia sp. 0.023 0.014 0.026 0.019 0.095 0.058 0.047 0.041 Cybocephalus sp. 0.037 0.029 0.190 0.252 0.366 0.166 0.059 0.077 Haplothrips sp. 0.026 0.017 0.033 0.027 0.192 0.133 0.750 0.103 Additional Declarations No competing interests reported. Supplementary Files Appendix1taxonomicassignements.docx Cite Share Download PDF Status: Published Journal Publication published 10 Jun, 2024 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 27 Jan, 2024 Reviews received at journal 25 Jan, 2024 Reviews received at journal 01 Dec, 2023 Reviewers agreed at journal 22 Nov, 2023 Reviewers agreed at journal 20 Nov, 2023 Reviewers invited by journal 17 Nov, 2023 Editor assigned by journal 17 Nov, 2023 Editor invited by journal 07 Nov, 2023 Submission checks completed at journal 07 Nov, 2023 First submitted to journal 26 Oct, 2023 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3496857","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":246863350,"identity":"527a9027-c288-4abb-b197-749762b8d6bf","order_by":0,"name":"Huei Ying 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Institute","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Gillian","middleName":"","lastName":"Maggs-Kölling","suffix":""},{"id":246863358,"identity":"15edf90f-9444-4b6f-a8f7-0deb68bec423","order_by":8,"name":"Hervé Bocherens","email":"","orcid":"","institution":"University of Tübingen","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hervé","middleName":"","lastName":"Bocherens","suffix":""}],"badges":[],"createdAt":"2023-10-27 01:44:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3496857/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3496857/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-024-61796-8","type":"published","date":"2024-06-10T14:49:16+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":46182306,"identity":"9f70afc1-ba60-4ba2-b507-6ee5a2e9820b","added_by":"auto","created_at":"2023-11-09 20:01:15","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":197666,"visible":true,"origin":"","legend":"\u003cp\u003eMean (±SD) δ\u003csup\u003e13\u003c/sup\u003eC and δ\u003csup\u003e15\u003c/sup\u003eN signatures of different basal resources (void shapes) and invertebrates (filled shapes) associated with different basal resources according to different colour and shapes: sand diamonds (\u003cem\u003eS. sabulicola\u003c/em\u003e), black squares (\u003cem\u003eA. horridus\u003c/em\u003e), and blue circle (hypolithic biomass).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3496857/v1/09c963f1c47f4398c508f633.png"},{"id":46182307,"identity":"ec816e5e-4e1a-49df-bdaa-602b8841dbe1","added_by":"auto","created_at":"2023-11-09 20:01:15","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":311139,"visible":true,"origin":"","legend":"\u003cp\u003e\u003csup\u003e15\u003c/sup\u003eN-enrichment of all above- and belowground invertebrates sampled from \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs as well as one species (\u003cem\u003eH. zigzagus\u003c/em\u003e) from \u003cem\u003eA. horridus\u003c/em\u003e. \u0026nbsp;signatures. TL = trophic level based on an enrichment factor of δ\u003csup\u003e15\u003c/sup\u003eN=3.4‰ per trophic level.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-3496857/v1/14921edd0b3b922a515714d4.png"},{"id":46182308,"identity":"f5d71690-3204-4533-a2d6-11f0a2f5cf4b","added_by":"auto","created_at":"2023-11-09 20:01:15","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":357754,"visible":true,"origin":"","legend":"\u003cp\u003eSummary of detritus and predatory food web according to stable isotope mixing models. Dotted red arrows indicate the detrital pathway while solid black arrows indicate predation.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-3496857/v1/af6c54ae4218f1a8d8be5d71.png"},{"id":58822094,"identity":"9a98c3c4-32b9-42b6-882a-2748d6bd654d","added_by":"auto","created_at":"2024-06-21 16:30:25","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1718115,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3496857/v1/20b10528-ae08-4f27-89d7-da83847f3930.pdf"},{"id":46182309,"identity":"b980d063-9907-4dbc-927d-ed6b398a729f","added_by":"auto","created_at":"2023-11-09 20:01:15","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":2322534,"visible":true,"origin":"","legend":"","description":"","filename":"Appendix1taxonomicassignements.docx","url":"https://assets-eu.researchsquare.com/files/rs-3496857/v1/6bb745bf82b300cfa2c15154.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Hidden Oases: Unveiling Trophic Dynamics in Namib's Fog Plant Ecosystem","fulltext":[{"header":"Introduction","content":"\u003cp\u003eFog oases are fertile vegetation islands that rely on fog condensation for their water supply. They have been widely studied in the \u003cem\u003elomas\u0026nbsp;\u003c/em\u003eformation in Peru and Chile\u0026nbsp;(Peru \u0026amp; P\u0026eacute;faur, 1982; Pinto et al., 2006; Rundel \u0026amp; Dillon, 1998), in the relic forests Fray Jorge (30\u0026deg;S) at the top of the coastal range (400 \u0026ndash; 650 m ASL) in Chile\u0026nbsp;(Gonzales et al., 2023), the redwood forest \u003cem\u003eSequoia sempervirens\u0026nbsp;\u003c/em\u003ein northern California (Dawson, 1998)\u0026nbsp;and the cloud forests of the central South Arabian mountains of Yemen and Oman\u0026nbsp;(Ball \u0026amp; Tzanopoulos, 2020). In the present study, we investigated \u0026ldquo;Fog-Plant-Oases\u0026rdquo; (FPOs), which operate on a significantly smaller scale and revolve around individual plants compared to previously studied fog oases that function at the community or ecosystem level. Beneath single grass tussocks of a fog-harvesting plant, soil hammocks or biogenic hillocks were formed, creating isolated islands with moisture and food availability\u0026nbsp;(Danin, 1991). The formation of soil hammocks is postulated to create stable conditions that encourage the utilization and colonization of such FPOs by other species as well as support the growth of the plant itself. Nonetheless, the function of FPOs, particularly by the fog-harvesting specialist \u003cem\u003eStipagrostis sabulicola\u0026nbsp;\u003c/em\u003e(\u003cem\u003ePoaceae\u003c/em\u003e)\u0026nbsp;(Ebner et al., 2011), as trophic hotspots for above- and belowground invertebrates have not been examined.\u003c/p\u003e\n\u003cp\u003eThe Namib Desert is a hyperarid coastal desert in which fog precipitation serves as a significant moisture source\u0026nbsp;(Frossard et al., 2015; Henschel \u0026amp; Seely, 2008; Lancaster \u0026amp; Seely, 1984). At our study area in the Namib Sand Sea, near Gobabeb (23\u0026deg;34\u0026rsquo;S 15\u0026deg;02\u0026rsquo;E), fog from the Atlantic Ocean is a more regular moisture source (39 mm mean annual condensation) than rainfall (21.2 mm mean annual precipitation) (Henschel, 2000). Advection fog condensation, where the moisture is derived from evaporation over the South Atlantic Ocean and transported inland by onshore winds, is mainly influenced by the distance from the coast and elevation\u0026nbsp;(Mitchell et al., 2020). To cope with the extreme dryness, a considerable number of endemic species of the flora and fauna of Namib have adapted to exploit atmospheric moisture\u0026nbsp;(Mitchell et al., 2020). An excellent example of how organisms adapted to extreme aridity in the Namib Desert and even shaped their environment is the formation of FPOs by the perennial endemic grass \u003cem\u003eS. sabulicola\u003c/em\u003e. As shown previously, \u003cem\u003eS. sabulicola\u003c/em\u003e possesses\u0026nbsp;specialized leaf structures that are highly effective at condensing moisture from the air\u0026nbsp;(Ebner et al., 2011; Roth-Nebelsick et al., 2012). Belowground, \u003cem\u003eS. sabulicola\u003c/em\u003e has a shallow but extensive root system for effective anchoring in the unstable and highly dynamic windblown sand and uptake of moisture condensing on the sand surface\u0026nbsp;(Louw \u0026amp; Seely, 1980). Overall, these studies have shown the distinctive morphological characteristics that enable \u003cem\u003eS. sabulicola\u003c/em\u003e to utilize fog water efficiently and stabilize Aeolian sand.\u003c/p\u003e\n\u003cp\u003eThe trophic structure in an ecosystem depicts its energy and nutrient transfers, commonly studied and illustrated through its food web\u0026nbsp;(Holt \u0026amp; Loreau, 2002). Despite their major importance in global biogeochemical cycling, the above- and belowground food webs of ecosystems are still poorly understood, mainly due to the huge diversity of soil-dwelling and aboveground organisms of which many are general feeders\u0026nbsp;(Crotty et al., 2014; Potapov et al., 2019; Scheu, 2002). This is exacerbated by the fact that food web studies are focused on certain land uses and climate regions, such as agricultural lands and temperate ecosystems\u0026nbsp;(Crotty et al., 2014; Potapov et al., 2019; Scheu, 2002). Therefore, there remains a need to continue exploring the trophic structure of both soil-dwelling and aboveground animal communities, particularly in arid and hyperarid ecosystems as they cover a high proportion of the Earth\u0026rsquo;s surface and due to their sensitivity to climate change (Nielsen \u0026amp; Ball, 2015; Quoreshi et al., 2022; Whitford W. G., 1996). Previously, only a couple of studies employed stable isotope analysis in understanding the belowground food web in a hyperarid desert, including the investigation of the diet of soil nematodes and tardigrades under biological soil crusts in the arid Southwest of US (Darby \u0026amp; Neher, 2012)\u0026nbsp;and the study of the diet of nematodes, tardigrades, rotifers, and microarthropods in the McMurdo Dry Valleys in Antarctica\u0026nbsp;(Shaw et al., 2018).\u003c/p\u003e\n\u003cp\u003eOur study presents the community composition and abundance of previously unexplored above- and belowground invertebrates found around the \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs. We hypothesized that the fog-harvesting efficiency of \u003cem\u003eS. sabulicola\u003c/em\u003e facilitates important ecological niches within the Namib Sand Dune ecosystem. Additionally, we proposed that the plant litter from \u003cem\u003eS. sabulicola\u003c/em\u003e serves as the primary carbon source for the FPO trophic structure, which fuels carbon flow from lower to higher trophic levels. To test these hypotheses, we aimed to measure the natural variations of \u0026delta;13C and \u0026delta;15N of above- and belowground invertebrates of the \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs, and to evaluate its trophic connections and food web. Isotopic analysis is based on the premise that the stable carbon and nitrogen isotopes (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN) of above- and belowground invertebrates reflect their diet compositions. This can be used to determine their trophic positions i.e., detritivores, secondary decomposers, herbivores, or predators within the soil web\u0026nbsp;(Ponsard \u0026amp; Arditi, 2000; Vanderklift \u0026amp; Ponsard, 2003).\u0026nbsp;Combined with isotope mixing models, a finer resolution of their diet compositions can be achieved (Govan et al., 2023; Parnell et al., 2013; Post, 2002).\u0026nbsp;In addition, due to the lack of rainfall that activates microbial decompositions in this hyperarid ecosystem (K. Jacobson et al., 2015; K. M. Jacobson \u0026amp; Jacobson, 1998), we further aimed to identify the main primary decomposers of the \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs by estimating the contributions of plant litter in their diets.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eDiversity and abundance of FPO fauna\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAboveground\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;fauna\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe overall composition of non-flying or poor flying arthropods were evaluated by bush-beating. Rapid flyers such as Diptera and Hymenoptera often escaped and thus were mostly not studied. Collected arthropods included: oribatid mites (\u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp., 100 specimens), beetles (\u003cem\u003eCybocephalus\u003c/em\u003e sp., 17 specimens, \u003cem\u003eExochmus flaviventris\u003c/em\u003e, 1 specimen), thrips (\u003cem\u003eHaplothrips\u003c/em\u003e sp\u003cem\u003e.\u003c/em\u003e, 15 specimens), barklice (\u003cem\u003eLiposcelis\u003c/em\u003e sp., 14 specimens), weevils (\u003cem\u003eSibinia\u003c/em\u003e sp\u003cem\u003e.\u003c/em\u003e, 13 specimens), pseudoscorpions (\u003cem\u003eNanolpium\u003c/em\u003e sp\u003cem\u003e.,\u0026nbsp;\u003c/em\u003e9 specimens), \u0026nbsp;leafhoppers (\u003cem\u003eDeltocephalinae\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e, 5 specimens), jumping spiders (\u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e, 2 specimens), ground sac spiders (\u003cem\u003eThysanina\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e, 1 specimen), and parasitoid wasps (\u003cem\u003eHaltichellinae\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e, 2 specimens). Peeling of plant stems revealed the occurrence of armoured scale insects (Diaspididae) and mealybugs (\u003cem\u003ePseudococcidae\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e) and again the oribatid mite \u003cem\u003eZygoribatula\u003c/em\u003e sp\u003cem\u003e.\u003c/em\u003e, under the leaf sheath near the nodes. Details on the taxonomic assignment of these species are provided in Appendix 1. Further groups observed on the leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e, but not studied in detail, included red velvet mites (Trombidiidae), predatory mites (Gamasina), and more insects: cockroaches (Blattodea, 1 specimen), grasshoppers (Orthoptera, 1 specimen), true bugs (Heteroptera, 1 specimen), flies (Diptera, several spp.) and parasitoid wasps (Hymenoptera, several spp.).\u003c/p\u003e\n\u003cp\u003eSupplementary collection of dune surface dwellers that frequently visit \u003cem\u003eS. sabulicola\u003c/em\u003e included dune ants (\u003cem\u003eCampotonous detritus\u003c/em\u003e), which\u003cem\u003e\u0026nbsp;\u003c/em\u003etends scale insects and leafhoppers to collect honeydew (Curtis, 1985b). These ants are more abundant on the base dunes as well as on the dune slope as compared to the high dunes. Ten individuals of tenebrionid beetles consisting of \u003cem\u003eOnymacris plana\u003c/em\u003e (4 specimens), \u003cem\u003ePhysadesmia globosa\u003c/em\u003e (3 specimens), and \u003cem\u003eOnymacris laeviceps\u0026nbsp;\u003c/em\u003e(3 specimens) were collected both from the high dunes as well as from the dune base near the Kuiseb Riverbed. As a comparison to the \u003cem\u003eS. sabulicola\u0026nbsp;\u003c/em\u003efood web, two individuals of blister beetles \u003cem\u003eHycleus zigzagus\u003c/em\u003e were included, which were the herbivores of the !Nara melon\u0026nbsp;(\u003cem\u003eAcanthosicyos horridus\u003c/em\u003e) that also occurs on the base of the dunes. \u003cem\u003eA. horridus\u003c/em\u003e is a perennial endemic shrub and another potential fog-harvesting FPO that grows alongside \u003cem\u003eS. sabulicola\u003c/em\u003e at the base of Namib dunes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eBelowground\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;fauna\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 5233 nematode individuals with a total biomass of 913.4 \u0026micro;g biomass (fresh weight) were extracted through wet extractions (Baermann method). Most individuals were found in soils (dune sands) under mature FPOs with the highest density in deeper soil layers (30-50 cm depth). The nematodes were predominantly bacterial feeders (84.8% of overall biomass) represented by the genera \u003cem\u003eAcrobeles, Cephalobus, Cervidellus, Chiloplacus, Elaphonema, Panagrobelus, Panagrolaimus, Zeldia\u003c/em\u003e\u003cem\u003e,\u003c/em\u003e and some juvenile \u003cem\u003eMesorhabditidae\u003c/em\u003e and \u003cem\u003eDiplogastridae\u003c/em\u003e. Fungal-feeding nematodes contributed to 14.7% of overall nematode biomass and consisted of \u003cem\u003eAphelenchoides, Aphelenchus, Ditylenchus, Paraphelenchus\u003c/em\u003e\u003cem\u003e,\u003c/em\u003e and a few \u003cem\u003eTylenchidae\u003c/em\u003e. \u0026nbsp;As a third feeding group, omnivorous nematodes were detected only sporadically, but due to their large body size still accounted for 0.5% of overall nematode biomass. Tardigrades were extracted from only 3 of the 84 soil samples. They belonged to the genus \u003cem\u003eHexapodibius\u003c/em\u003e and were found with 3, 5, and 5 specimens under matured FPOs at 5-10 cm soil depth. Also, some mites (Pediculochelidae sp.) were found in very low numbers. Dry extractions (Berlese method) of another subset of 84 soil samples did not yield any animals, and only small amounts of nematodes, which were not analysed, were caught in underground pitfalls. Flotation (84 samples) yielded altogether 121 mites (Micropasmmidae sp., Pediculochelidae sp., and some Astigmata (not further analysed)) and the remains of a single springtail (cuticle of an \u003cem\u003eEntomobryidae\u003c/em\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStable isotope values\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of basal resources\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe average \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of different parts of \u003cem\u003eS. sabulicola\u003c/em\u003e spanned only 1.4\u0026permil; between -13.7 and -15.1\u0026permil; (Table 1). The fresh leaves were \u003csup\u003e13\u003c/sup\u003eC-depleted (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -15.1\u0026plusmn;0.7\u0026permil;) compared to dead leaves (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.0\u0026plusmn;0.6\u0026permil;) and dead leaves with visible fungal colonization (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.0\u0026plusmn;0.5\u0026permil;). Belowground, plant roots had isotopic values of \u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.1\u0026plusmn;0.3\u0026permil;, and rhizosheaths \u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -13.7\u0026plusmn;0.4\u0026permil;. Soil detritus (light fraction organic matter) extracted from hummocks of mature FPOs had \u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.3\u0026plusmn;0.2\u0026permil; values. The average \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of different parts of \u003cem\u003eS. sabulicola\u003c/em\u003e spanned almost 4\u0026permil; between -1.9\u0026permil; and 2.0\u0026permil;. The \u0026delta;\u003csup\u003e15\u003c/sup\u003eN of fresh leaves were close to the atmospheric \u0026delta;\u003csup\u003e15\u003c/sup\u003eN value of \u0026delta;\u003csup\u003e15\u003c/sup\u003eN = 0.2\u0026plusmn;1.5\u0026permil;. Dead leaves (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = -1.9\u0026plusmn;1.6\u0026permil;) and dead leaves with visible fungal colonies (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = -0.7\u0026plusmn;2.5\u0026permil;) were \u003csup\u003e15\u003c/sup\u003eN-depleted when compared to fresh leaves. Belowground, plant root (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = 0.1\u0026plusmn;1.4\u0026permil;) and rhizosheath (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = 0.8\u0026plusmn;0.4\u0026permil;) were \u003csup\u003e15\u003c/sup\u003eN-enriched in comparison to fresh leaves; while dead leaves with soil detritus (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = 2.0\u0026plusmn;1.2\u0026permil;) \u0026nbsp;were enriched in \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values compared toplant samples.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCompared to \u003cem\u003eS. sabulicola\u003c/em\u003e, which had \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values typical of C\u003csub\u003e4\u003c/sub\u003e plants, the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of \u003cem\u003eA. horridus\u003c/em\u003e litter resembled those of typical C\u003csub\u003e3\u003c/sub\u003e plants (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -21.7\u0026plusmn;0.8\u0026permil;). Soil detritus under \u003cem\u003eA. horridus\u0026nbsp;\u003c/em\u003e(\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -17.1\u0026plusmn;1.2\u0026permil;) were markedly \u003csup\u003e13\u003c/sup\u003eC-depleted compared to the dead leaves and soil detritus of \u003cem\u003eS. sabulicola\u003c/em\u003e. Compared to the litter and detritus of \u003cem\u003eS. sabulicola\u003c/em\u003e, the plant litter (dead stem) of \u003cem\u003eA. horridus\u003c/em\u003e (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = 4.2\u0026plusmn;1.6\u0026permil;) and soil detritus under \u003cem\u003eA. horridus\u003c/em\u003e (\u0026delta;\u003csup\u003e15\u003c/sup\u003eN = 3.7\u0026plusmn;0.2\u0026permil;) were \u003csup\u003e15\u003c/sup\u003eN-enriched.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of invertebrates\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA subset of the above-mentioned above- and belowground invertebrates were included in the stable isotope analysis for the construction of FPO trophic structure (Figure\u0026nbsp;1). Aboveground, invertebrates that have \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values close to the dead leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.0\u0026plusmn;0.6\u0026permil;) include the saprophilous and fungivorous \u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.7\u0026plusmn;0.7\u0026permil;), sap feeders \u003cem\u003eDeltocephalinae\u0026nbsp;\u003c/em\u003esp.\u003cem\u003e\u0026nbsp;\u003c/em\u003e(\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -13.9\u0026plusmn;0.4\u0026permil;) and Diapsididae\u003cem\u003e\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u0026nbsp;\u003c/em\u003e(\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -15.7\u0026plusmn;0.8\u0026permil;). Saprophilous and fungivorous \u003cem\u003eLiposcelis\u003c/em\u003e sp\u003cem\u003e.\u0026nbsp;\u003c/em\u003ewas markedly \u003csup\u003e13\u003c/sup\u003eC-depleted (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -20.6\u0026plusmn;3.3\u0026permil;) compared to the fresh leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -15.1\u0026plusmn;0.7\u0026permil;). Similarly, the herbivores \u003cem\u003eSibinia\u003c/em\u003e sp\u003cem\u003e.\u0026nbsp;\u003c/em\u003e(\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -21.0\u0026plusmn;1.6\u0026permil;) and \u003cem\u003eHaplothrips\u003c/em\u003e sp. (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -17.8\u0026plusmn;1.9\u0026permil;) were \u003csup\u003e13\u003c/sup\u003eC-depleted compared to the fresh leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e. Dune surface dwellers were also \u003csup\u003e13\u003c/sup\u003eC-depleted compared to the dead leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e including \u003cem\u003eC. detritus\u003c/em\u003e:\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -15.8\u0026plusmn;1.8\u0026permil;\u003cem\u003e, O. laeviceps\u003c/em\u003e:\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -16.0\u0026plusmn;1.5\u0026permil;\u003cem\u003e,\u003c/em\u003e and\u003cem\u003e\u0026nbsp;O. plana\u003c/em\u003e:\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -17.2\u0026plusmn;2.0\u0026permil;\u003cem\u003e,\u003c/em\u003e while the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of \u0026nbsp;\u003cem\u003eP. globosa\u003c/em\u003e were markedly depleted (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -25.2\u0026plusmn;0.6\u0026permil;) compared to the tenebrionid beetles from the genus \u003cem\u003eOnymacris\u003c/em\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePredators \u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.1\u0026plusmn;0.3\u0026permil;) and parasitoids \u003cem\u003eHaltichellinae\u0026nbsp;\u003c/em\u003esp. (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.0\u0026plusmn;0.3\u0026permil;) had \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values almost identical to the dead leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -14.0\u0026plusmn;0.6\u0026permil;). Scale insects predator \u003cem\u003eCybocephalus\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u0026nbsp;\u003c/em\u003e(\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -13.5\u0026plusmn;0.2\u0026permil;) and predator \u0026nbsp;\u003cem\u003eThysanina\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -12.8\u0026permil;) was 0.5-1.2 \u0026permil; \u003csup\u003e13\u003c/sup\u003eC-enriched compared to the same plant material. In contrast, the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC value of \u003cem\u003eNanolpium\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u0026nbsp;\u003c/em\u003e(\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -18.4\u0026plusmn;2.5\u0026permil;) was markedly \u003csup\u003e13\u003c/sup\u003eC-depleted compared to the dead leaves of \u003cem\u003eS. sabulicola\u0026nbsp;\u003c/em\u003eas well as other predatory species. The summary of aboveground invertebrates, their expected trophic feeding types, and isotopic values are summarised in Table\u0026nbsp;2. Belowground, both bacterial- (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -24.6\u0026plusmn;1.9\u0026permil;) and fungal-feeding nematodes (\u0026delta;\u003csup\u003e13\u003c/sup\u003eC = -23.6\u0026plusmn;0.2\u0026permil;) were markedly \u003csup\u003e13\u003c/sup\u003eC-depleted compared to dead leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eValues of \u0026delta;\u003csup\u003e15\u003c/sup\u003eN in a consumer\u0026rsquo;s tissue are more \u003csup\u003e15\u003c/sup\u003eN-enriched compared to those of its diet, and this is termed \u0026ldquo;enrichment\u0026rdquo; as denoted by ∆, where ∆\u003csup\u003e15\u003c/sup\u003eN = \u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003econsumer\u003c/sub\u003e - \u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003ediet\u003c/sub\u003e (Eq. 1). In the present study, ∆\u003csup\u003e15\u003c/sup\u003eN values were used to calculate trophic positions (TP) of above- and belowground invertebrates at the \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs, where dead leaves of the fog plant were assumed to form the trophic base (∆\u003csup\u003e15\u003c/sup\u003eN = 0) of the invertebrate food web. Calculation of trophic positions assumes the enrichment factor per trophic level equals 3.4\u0026permil; according to a previous large-scale study on marine and freshwater organisms by Minagawa \u0026amp; Wada (1984). Therefore, Eq. 1 is rewritten as TP = [\u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003einvertebrate\u003c/sub\u003e - \u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003ebaseline\u003c/sub\u003e]\u003csub\u003e\u0026nbsp;\u003c/sub\u003e/ 3.4,\u003csub\u003e\u0026nbsp;\u003c/sub\u003ewhere \u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003einvertebrate\u003c/sub\u003e = \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of above- and belowground invertebrates found on or within proximity to \u003cem\u003eS. sabulicola\u003c/em\u003e, and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003ebaseline\u003c/sub\u003e = dead leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e. Likewise, the \u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003csub\u003ebaseline\u003c/sub\u003e to calculate the trophic position of \u003cem\u003eH. zigzagus\u003c/em\u003e, the herbivore species found feeding on \u003cem\u003eA. horridus\u003c/em\u003e, was assumed to be the \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of dead \u003cem\u003eA. horridus\u0026nbsp;\u003c/em\u003estem.\u003c/p\u003e\n\u003cp\u003eOverall, the gradient spanned over 16 \u0026delta; units in ∆\u003csup\u003e15\u003c/sup\u003eN values for all FPO invertebrates that occupied 5 trophic positions. The first trophic position was occupied by primary decomposers including \u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp.\u003cem\u003e\u0026nbsp;\u003c/em\u003e(∆\u003csup\u003e15\u003c/sup\u003eN = 0.05\u0026plusmn;0.6\u0026permil;) and \u003cem\u003eLiposcelis\u003c/em\u003e sp. (∆\u003csup\u003e15\u003c/sup\u003eN = 2.8\u0026plusmn;1.9\u0026permil;) as well as sap feeder \u003cem\u003eDiapsididae\u0026nbsp;\u003c/em\u003esp.\u003cem\u003e\u0026nbsp;\u003c/em\u003e(∆\u003csup\u003e15\u003c/sup\u003eN = 0.9\u0026plusmn;0.6\u0026permil;). The second trophic level was occupied by the most taxa with various feeding strategies, including sap feeder \u003cem\u003eDeltocephalinae\u003c/em\u003e sp. (∆\u003csup\u003e15\u003c/sup\u003eN = 3.2\u0026plusmn;1.2\u0026permil;), predators \u003cem\u003eThysanina\u003c/em\u003e sp. (∆\u003csup\u003e15\u003c/sup\u003eN = 4.0\u0026permil;)\u003cem\u003e, Nanolpium sp.\u0026nbsp;\u003c/em\u003e(∆\u003csup\u003e15\u003c/sup\u003eN = 5.5\u0026plusmn;0.7\u0026permil;)\u003cem\u003e,\u0026nbsp;\u003c/em\u003eand \u003cem\u003eCybocephalus\u003c/em\u003e sp. (∆\u003csup\u003e15\u003c/sup\u003eN = 5.9\u0026plusmn;2.8\u0026permil;)\u003cem\u003e,\u003c/em\u003e bacterial-feeding nematodes (∆\u003csup\u003e15\u003c/sup\u003eN = 5.4\u0026plusmn;1.2\u0026permil;), as well as herbivore \u003cem\u003eH.\u0026nbsp;zigzagus\u003c/em\u003e (∆\u003csup\u003e15\u003c/sup\u003eN = 6.2\u0026plusmn;1.1\u0026permil;), and honeydew feeder \u003cem\u003eC. detritus\u003c/em\u003e (∆\u003csup\u003e15\u003c/sup\u003eN = 6.6\u0026plusmn;0.9\u0026permil;)\u003cem\u003e.\u0026nbsp;\u003c/em\u003eBoth tenebrionid species occupied the third trophic level: \u003cem\u003eO. laeviceps\u0026nbsp;\u003c/em\u003e(∆\u003csup\u003e15\u003c/sup\u003eN = 6.7\u0026plusmn;5.0\u0026permil;) and \u003cem\u003eO. plana\u003c/em\u003e (∆\u003csup\u003e15\u003c/sup\u003eN = 7.2\u0026plusmn;1.8\u0026permil;). \u003cem\u003eP. globosa\u003c/em\u003e is excluded from trophic level calculation because of their distinctive \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values and lack of a suitable baseline value. The fourth trophic level was occupied by \u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp.\u0026nbsp;(∆\u003csup\u003e15\u003c/sup\u003eN = 10.9\u0026plusmn;0.9\u0026permil;) and \u003cem\u003eHaplothrips\u0026nbsp;\u003c/em\u003esp.\u003cem\u003e\u0026nbsp;\u003c/em\u003e(∆\u003csup\u003e15\u003c/sup\u003eN = 11.4\u0026plusmn;2.5\u0026permil;)\u003cem\u003e,\u0026nbsp;\u003c/em\u003ewhile \u003cem\u003eSibinia\u0026nbsp;\u003c/em\u003esp. (∆\u003csup\u003e15\u003c/sup\u003eN = 13.7\u0026plusmn;1.4\u0026permil;) and \u003cem\u003eHaltichellinae\u003c/em\u003e sp. (∆\u003csup\u003e15\u003c/sup\u003eN = 16.7\u0026plusmn;0.4\u0026permil;) occupied the fifth trophic level. Fungal-feeding nematodes were positioned way below the trophic baseline due to their markedly low ∆\u003csup\u003e15\u003c/sup\u003eN value (-11.04 \u0026plusmn; 3.90\u0026permil;).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiet estimates of FPO invertebrates\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEstimates for the diet of aboveground invertebrates were conducted using the\u0026nbsp;Stable Isotope Mixing Models (function \u0026ldquo;simmr\u0026rdquo;)\u0026nbsp;(Govan et al., 2023). The analyses were based on both the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of consumers (mixtures) as well as their potential diets (sources). Corrections were considered for the analyses, which included the standard deviations for consumers\u0026rsquo; \u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values, the % of carbon\u0026nbsp;and nitrogen of diet, as well as enrichment factors for \u003csup\u003e13\u003c/sup\u003eC=0.4\u0026plusmn;1.3\u0026permil; and \u003csup\u003e15\u003c/sup\u003eN=3.4\u0026plusmn;1.0\u0026permil; according to Post (2002). Mixing models were used to estimate\u0026nbsp;i)\u0026nbsp;the contributions of dead leaf, soil detritus, and scale insects (\u003cem\u003eDiaspididae\u0026nbsp;\u003c/em\u003esp.)\u003cem\u003e\u0026nbsp;\u003c/em\u003eto\u0026nbsp;the diet of primary as well as secondary decomposers\u0026nbsp;and ii) the contributions of lower ranked invertebrates to the diet of predatory taxa.\u003c/p\u003e\n\u003cp\u003eEstimations of potential dietary components of the sampled invertebrates varied markedly as indicated by high standard deviations (Table\u0026nbsp;3\u0026nbsp;and Table\u0026nbsp;4). Nevertheless, the estimates suggested that fungal-infected dead leaves of \u003cem\u003eS. sabulicola\u003c/em\u003e constituted a large proportion in the diet of \u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp. (78\u0026plusmn;27%) and \u003cem\u003eCybocephalus\u0026nbsp;\u003c/em\u003esp. (67\u0026plusmn;17%). Soft scales \u003cem\u003eDiaspididae\u0026nbsp;\u003c/em\u003esp. had substantial contributions to the diets of \u003cem\u003eLiposcelis\u0026nbsp;\u003c/em\u003esp. (73\u0026plusmn;42%), \u003cem\u003eO. laeviceps\u0026nbsp;\u003c/em\u003e(78\u0026plusmn;19%), and \u003cem\u003eO. plana\u0026nbsp;\u003c/em\u003e(89\u0026plusmn;5%). Soil detritus which comprised of light fraction organic matter under \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs showed an important contribution to the diet of \u003cem\u003eC. detritus\u003c/em\u003e (86\u0026plusmn;18%).\u0026nbsp;Among predatory taxa that occupy lower trophic levels (TL),\u0026nbsp;\u003cem\u003eLiposcelis\u003c/em\u003e sp.\u0026nbsp;contributed 65\u0026plusmn;10% to the diet of\u0026nbsp;\u003cem\u003eNanolpium\u003c/em\u003e sp.\u0026nbsp;(TL= 2) while\u0026nbsp;\u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp. contributed 46\u0026plusmn;31% to the diet of\u0026nbsp;\u003cem\u003eThysanina\u003c/em\u003e sp.\u0026nbsp;(TL= 2). Among the \u0026ldquo;higher\u0026rdquo; predatory taxa,\u0026nbsp;\u003cem\u003eCybocephalus\u003c/em\u003e sp.\u0026nbsp;contributed 37\u0026plusmn;17% to the diet of\u0026nbsp;\u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp.\u0026nbsp;(TL= 4) while\u0026nbsp;\u003cem\u003eHaplothrips\u0026nbsp;\u003c/em\u003esp.\u0026nbsp;contributed 75\u0026plusmn;10% to the diet of\u0026nbsp;\u003cem\u003eHaltichellinae\u003c/em\u003e sp. (TL = 5). The summary of the trophic relationships was shown in Figure 3.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe ability of \u003cem\u003eS. sabulicola\u0026nbsp;\u003c/em\u003eto establish itself in barren environments from the seedling stage classifies it as a pioneer species. However, unlike most pioneer species which were eventually replaced by other successional species once stable conditions are achieved, \u003cem\u003eS. sabulicola\u003c/em\u003e continues to grow into large grass tussocks\u0026nbsp;with hummock formations and ultimately become the climax species. The persistence of \u003cem\u003eS. sabulicola\u003c/em\u003e as the only plant species on the higher dunes can be attributed to two main mechanisms. Firstly, the fog plant possesses distinctive morphology that enables it to harvest fog and exploit near-surface moisture effectively, as well as to anchor itself on the highly unstable sand dunes\u0026nbsp;(Ebner et al., 2011; Louw \u0026amp; Seely, 1980; Roth-Nebelsick et al., 2012).\u0026nbsp;Secondly, abiotic factors such as the rapid sand movement on the dunes and scarce rainfall hinder the succession of the fog and dune specialists by other plant species (Yeaton, 1988). Overall, the unusual formation of \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs highlights their potential as habitats for various invertebrates and a unique food web. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn this study, we illustrated that \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs harbor trophic niches for a diverse array of above- and belowground invertebrates. Aboveground through bush-beating, we found a total of 12 arthropod taxa on the leaf surface and within the leaf sheaths, with an additional 7 taxa observed, but not studied in detail. In contrast, flotation of soil samples yielded only a few soil microarthropod species which were predominantly mites. Belowground microarthropods under \u003cem\u003eS. sabulicola\u003c/em\u003e hummock were previously recognized by Coineau \u0026amp; Seely (1983). They retrieved a higher diversity of taxa than us, especially with the findings of Arthropleona springtails (a single cuticle found by us). Their sampling methodology differed from ours, as they frequently watered a well in the sand for one week before sampling 10 L of sands. Our sampling design was likely not sensitive enough to capture the rare taxa (Pauropoda). From the cuticle we found, we suspect the reported Arthropleona to belong to a rather common, yet undescribed, Entomobryidae we observed in the Kuiseb and in Gobabeb. The species is a rapid runner that could have rapidly aggregated in the watered well while being scarce in the natural conditions targeted by our sampling. Though bush-beating and soil sampling are difficult to compare, arthropod species richness and biomass were evidently higher on the grass canopy of \u003cem\u003eS. sabulicola\u003c/em\u003e than in the sand near the roots, revealing the complexity of these \u0026ldquo;hidden oases\u0026rdquo;. Soil life is probably inhibited by the instability of the dune surface\u0026nbsp;(Scholz, 1972), but the presence of a thriving fauna community on the aboveground canopy was undeniably enabled by an ample supply of fog water stored in the grooved stems of \u003cem\u003eS. sabulicola\u003c/em\u003e (Ebner et al., 2011). Sufficient wetting of aboveground litter has also been previously observed to undergo rapid fungal decomposition which additionally provides aboveground fauna with high-quality litter\u0026nbsp;\u0026nbsp;(K. Jacobson et al., 2015). Overall, the presence of moisture, food sources, and potential wind and solar protection provided by the grass tussock canopy collectively render it a suitable habitat for the discovered invertebrates.\u003c/p\u003e\n\u003cp\u003eAmong the aboveground soil invertebrates that have similar \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values as \u003cem\u003eS. sabulicola\u003c/em\u003e, their trophic levels were observed to span from the detritivore (\u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp\u003cem\u003e.\u003c/em\u003e) to the predatory taxa (\u003cem\u003eCybocephalus\u003c/em\u003e sp. to \u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp.\u003cem\u003e,\u003c/em\u003e and \u003cem\u003eHaltichellinae\u0026nbsp;\u003c/em\u003esp.). This points to \u003cem\u003eS. sabulicola\u003c/em\u003e as the primary source of carbon that fuelled the aboveground FPO food web from the bottom to the higher trophic levels (Figure\u0026nbsp;2, Figure 3). However, the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of the other half of the FPO invertebrates were found to be \u003csup\u003e13\u003c/sup\u003eC-depleted, some markedly, compared to the litter of \u003cem\u003eS. sabulicola\u003c/em\u003e. For instance, \u003cem\u003eLiposcelis\u003c/em\u003e sp\u003cem\u003e.\u0026nbsp;\u003c/em\u003ewas about 6\u0026permil; depleted compared to the litter of \u003cem\u003eS. sabulicola\u003c/em\u003e. However, it is not clear if the markedly depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of this saprophilous and fungivorous species mirrored the plant sap of \u003cem\u003eS. Sabulicola\u003c/em\u003e, since \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of phloem sap have been previously reported to be like plant leaves\u0026nbsp;(Sagers \u0026amp; Goggin, 2007). Depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values compared to \u003cem\u003eS. sabulicola\u003c/em\u003e were also apparent in \u003cem\u003eHaplothrips\u0026nbsp;\u003c/em\u003esp. and \u003cem\u003eSibinia\u003c/em\u003e sp., both typically classified as plant herbivores. Moreover, the phenomenon of markedly depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values among plant herbivores seemed to occur only within the FPO soil food web, whereas \u003cem\u003eH. zigzagus\u003c/em\u003e, the arthropod that fed on the stem of \u003cem\u003eA. horridus\u003c/em\u003e, showed a 3\u0026permil; enrichment in\u0026nbsp;\u0026delta;\u003csup\u003e13\u003c/sup\u003eC\u0026nbsp;compared to its host plant.\u003c/p\u003e\n\u003cp\u003eAs mentioned above, the markedly depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of some of the plant herbivores of the FPOs differed from earlier studies that reported a trend of increasing \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values moving up the trophic level\u0026nbsp;(Ponsard \u0026amp; Arditi, 2000; Scheu \u0026amp; Falca, 2000).\u0026nbsp;Past research has reported variations in \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of different primary and secondary photosynthetic products from various temperate plants e.g. \u003csup\u003e13\u003c/sup\u003eC-enriched sucrose and starch and \u003csup\u003e13\u003c/sup\u003eC-depleted lignin and lipid (Gleixner et al., 1993). Therefore, these\u0026nbsp;herbivore\u0026nbsp;species\u0026nbsp;yet with distinct\u0026nbsp;\u0026delta;\u003csup\u003e13\u003c/sup\u003eC values\u0026nbsp;compared to their host plant\u0026nbsp;may be feeding on specific types of photosynthetic products with depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values than the bulk leaves or litter of \u003cem\u003eS. sabulicola\u003c/em\u003e. Apart from diet, the lower \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values could also be explained by higher lipid content in animal tissues, which is generally more \u003csup\u003e13\u003c/sup\u003eC-depleted compared to proteins and carbohydrates. The depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values due to higher lipid content are shown by negative correlations between invertebrate C/N ratios and their \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values (Focken \u0026amp; Becker, 1998; Post et al., 2007). Overall, we found significant negative correlations between the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of \u003cem\u003eLiposcelis\u003c/em\u003e sp\u003cem\u003e.\u003c/em\u003e and their C/N ratios (adjusted R-squared = 0.93, p-value = \u0026lt;0.001) which supports this hypothesis, but no correlation between \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values and C/N ratios were found for \u003cem\u003eHaplothrips\u0026nbsp;\u003c/em\u003esp. and \u003cem\u003eSibinia\u003c/em\u003e sp. Additionally, we discovered that the FPO invertebrates showed a pattern of lower C/N ratios (Table\u0026nbsp;2) compared to soil invertebrates from temperate forests and grasslands\u0026nbsp;(Crotty et al., 2014; Ponsard \u0026amp; Arditi, 2000). This finding suggests that climatic influence, in this case hyperaridity, may be driving these differences. This hypothesis is supported by prior studies which demonstrated that lipid storage plasticity is associated with starvation tolerance in arthropods under temperature manipulations (Jensen et al., 2018; van Dooremalen \u0026amp; Ellers, 2010).\u003c/p\u003e\n\u003cp\u003eGiven the importance of detritivores in the decomposition of plant litter outside of rain events in the Namib Desert\u0026nbsp;(K. Jacobson et al., 2015; K. M. Jacobson \u0026amp; Jacobson, 1998), we further focused on the diet of detritivore species at FPOs. In the present study, we found oribatid mites from the genus \u003cem\u003eZygoribatula\u003c/em\u003e sp. to be the most abundant primary decomposer species inhabiting the leaves of \u003cem\u003eS. sabulicola.\u003c/em\u003e Previous studies have reported that oribatid mites from the same genus, \u003cem\u003eZygoribatula exilis,\u003c/em\u003e exclusively occupy trees or lichens\u0026nbsp;(Fischer et al., 2010). Isotope data from prior studies on \u003cem\u003eZ. exilis\u003c/em\u003e in temperate forests indicated a slight \u003csup\u003e15\u003c/sup\u003eN-enrichment relative to the tree barks, implying that they feed on algae and bryophyte\u0026nbsp;(Erdmann et al., 2007). Similarly, our diet estimates showed a majority contribution of dead leaves with heavy fungal infection to the diets of \u003cem\u003eZygoribatula\u003c/em\u003e sp., thus highlighting their importance as the main primary decomposer of the \u003cem\u003eS. sabulicola\u003c/em\u003e FPOs and potentially helping to control fungal pathogens of the fog plant.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe further investigated the roles of tenebrionid beetles and dune ants as potentially important detritivores of the\u003cem\u003e\u0026nbsp;S. sabulicola\u003c/em\u003e FPOs. Our stable isotope data confirmed the niche separation between \u003cem\u003eP. globosa\u003c/em\u003e and other tenebrionid beetles from the genus \u003cem\u003eOnymacris\u003c/em\u003e (Figure 2). In agreement with previous studies, we showed that specimens from the genus \u003cem\u003eOnymacris\u003c/em\u003e tend to inhabit open sand and vegetation-less dune slips compared to \u003cem\u003eP. globosa\u003c/em\u003e which occupies the dry riverbeds and the gravel plains\u0026nbsp;(Osberg et al., 1986; Roberts et al., 1991). In terms of diets, our estimates showed that the leaf litter of \u003cem\u003eS. sabulicola\u003c/em\u003e did not have significant contributions as food resources for \u003cem\u003eO. laeviceps\u003c/em\u003e and \u003cem\u003eO. plana\u003c/em\u003e. Furthermore, the tenebrionid beetles also occupy a rather high trophic level like other predators. Previously, wind-blown litter has been suggested to dominate the diet of these species\u0026nbsp;(Holm \u0026amp; Edney, 1973), but our stable isotope data provide evidence that plant litter plays a less important role in their diets compared to other food sources with higher \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values, such as a diet rich\u0026nbsp;in\u0026nbsp;animal-derived sources. The dune ants \u003cem\u003eC. detritus\u003c/em\u003e, while proficient at clearing surface detritus, do not function as detritus consumers themselves\u0026nbsp;(Curtis, 1985a). Instead, they primarily subsist on a diet of honeydews, which are secreted by aphids and scale insects\u0026nbsp;(Curtis, 1985b). In line with this, we observed that the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of \u003cem\u003eC. detritus\u003c/em\u003e closely mirrored those of the Diaspididae sp. that were notably abundant within the inner sheath of \u003cem\u003eS. sabulicola\u003c/em\u003e. However, diet estimates also showed a high contribution of soil detritus in the diet of \u003cem\u003eC. detritus\u003c/em\u003e, confirming the large diet spectrum of this generalist feeder. In summary, these results indicate that \u003cem\u003eO. laeviceps, O. plana\u003c/em\u003e, and \u003cem\u003eC. detritus\u003c/em\u003e were not the main consumers of \u003cem\u003eS. sabulicola\u003c/em\u003e\u0026apos;s litter\u003cem\u003e,\u003c/em\u003e and likely played a smaller role than \u003cem\u003eZygoribatula sp.\u0026nbsp;\u003c/em\u003ein the decomposition of plant litter within the FPOs.\u003c/p\u003e\n\u003cp\u003eBelowground, soil nematodes were predominantly bacterial feeders (bacterivores) followed by fungal feeders (fungivores), which mirrors their trophic composition of the well-studied gravel plains nearby\u0026nbsp;and other arid ecosystems\u0026nbsp;(Marais et al., 2020; Pen-Mouratov et al., 2004; Steinberger Y. et al., 1988; Treonis et al., 2022). Overall, the markedly depleted \u0026delta;\u003csup\u003e13\u003c/sup\u003eC values of both trophic groups of nematodes compared to the litter of \u003cem\u003eS. sabulicola\u003c/em\u003e suggest that the fog plant might not be their main carbon source.\u0026nbsp;Compared to the\u0026nbsp;\u0026delta;\u003csup\u003e13\u003c/sup\u003eC values\u0026nbsp;of aboveground invertebrates which in general resemble\u0026nbsp;\u0026delta;\u003csup\u003e13\u003c/sup\u003eC values\u0026nbsp;of\u0026nbsp;\u003cem\u003eS. Sabulicola\u003c/em\u003e, the\u0026nbsp;\u0026delta;\u003csup\u003e13\u003c/sup\u003eC values\u0026nbsp;of belowground fauna indicate that their main energy source originated from\u0026nbsp;wind-blown sediments. The distinct energy sources between the above- and the belowground food web suggest two separate niches.\u0026nbsp;According to their \u003csup\u003e15\u003c/sup\u003eN-enrichment (∆\u003csup\u003e15\u003c/sup\u003eN), bacterivores occupied the second trophic level of the FPO food web, confirming their trophic roles as secondary decomposers\u0026nbsp;(Kudrin et al., 2015; Melody et al., 2016). Markedly depleted ∆\u003csup\u003e15\u003c/sup\u003eN values, however, positioned the fungivorous nematodes way below the baseline of the \u003cem\u003eS. sabulicula\u003c/em\u003e plant tissues, showing similar values as lichen-feeding oribatid mites in a temperate forest (Erdmann et al., 2007). To the best of our knowledge, there is no other in-situ comparison of\u0026nbsp;\u0026delta;\u003csup\u003e15\u003c/sup\u003eN values\u0026nbsp;among fungal-feeding nematodes\u0026nbsp;in the current literature. Results from a feeding experiment conducted by Ruess et al. (2004) showed that the depleted ∆\u003csup\u003e15\u003c/sup\u003eN of fungivores\u0026nbsp;\u003cem\u003eAphelenchoides\u0026nbsp;saprophilus\u003c/em\u003e originated from its fungal food source that was depleted in ∆\u003csup\u003e15\u003c/sup\u003eN compared to the medium where the fungi grew. Together with these previous findings, our results indicate\u0026nbsp;that depleted ∆\u003csup\u003e15\u003c/sup\u003eN of fungivores may be related to feeding on low-quality food sources such as blown-in detritus, lichens, or fungal biomass\u0026nbsp;which is typically N-depleted (Mouginot et al., 2014), as well as mechanisms of \u003csup\u003e15\u003c/sup\u003eN fractionations by nematode to compensate for low-quality food resources.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003eSite description\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted in the Namib Sand Sea near the Gobabeb Namib Research Institute (23\u0026deg;34\u0026rsquo;S, 15\u0026deg;03\u0026rsquo; E, 407m a.s.l., ~1km south across the Kuiseb River). \u003cem\u003eS. sabulicola\u003c/em\u003e is the dominant plant species growing on the Aeolian dunes, particularly the plinth (flattened slope on the dune base) and the windward slopes (Robinsonj \u0026amp; Seely, 1980; Southgate et al., 1996). At the dune base, \u003cem\u003eS. sabulicola\u0026nbsp;\u003c/em\u003ewas found to coexist with other \u003cem\u003eStipagrostis\u003c/em\u003e species, \u003cem\u003eAcanthosicyos horridus\u003c/em\u003e (!Nara melon) and \u003cem\u003eCladoraphis spinosa\u003c/em\u003e. A total of seven FPOs established by \u003cem\u003eS. sabulicola\u003c/em\u003e with two contrasting grass tussock sizes (3 young and 7 mature tussocks with signs of senescence) were selected as study sites. Mature and young FPOs referred to growth stages of \u003cem\u003eS. sabulicola\u003c/em\u003e that forms the FPO. At mature FPOs, sizable sand hummocks (up to 10m x 9m wide) were formed by tussocks that frequently grow up to 2 meters tall, while young plants (under 1 meter in height) did not accumulate visible hummocks yet. Open sand next to the FPOs were assigned as controls. All three young FPOs and two mature FPOs were located on dune ridges, while two mature FPOs were located on the windward plinth and dune base respectively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSampling and processing of samples\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eField work and sampling of all study materials were carried out during the fog season in early September 2022. Samples for extracting soil nematodes and other belowground invertebrates consisted of two replicates (one for wet extractions for nematodes and one for other fauna) of 3-4 soil cores each per FPO (diameter 5cm, height 5cm), with 84 samples in total.\u0026nbsp;Immediately after sampling, nematodes were extracted from soil samples using a modified Baermann method (wet extraction) for 48 hours. In this study, we used \u0026quot;soil\u0026quot; as a generic term for \u0026quot;ground substrate\u0026quot;, which in this case refers to sandy substrate from the dunes.\u0026nbsp;At the end of the extraction, nematodes were heat-killed and fixed with formaldehyde. The nematodes were identified to genus level, and where possible to species, under an inverted microscope (400x magnification). The body length and width of each specimen was measured and translated into body mass using the formula of Andrass\u0026yacute; (1956). Nematode genera were assigned to bacterivorous, fungivorous, and omnivorous feeding types following Yeates et al. (1993). \u0026nbsp;Several adults from each genus were isolated for preparation on permanent slides and species determination. The remaining bacterivores yielded sufficient biomass for isotope analysis, hence were hand picked under the inverted microscope in two samples, which weighed 48.5 and 105.8 \u0026micro;g dried nematode mass, respectively. The numbers and biomass of fungivorous nematodes did not suffice, thus two samples containing both bacterivores and fungivores were weighed together. Since in both of these pooled samples, the biomass ratios of the two trophic groups (m\u003csub\u003ebac\u003c/sub\u003e and m\u003csub\u003efun\u003c/sub\u003e) were accurately measured, and the isotopic signal for bacterivores (F\u003csub\u003ebac\u003c/sub\u003e) was already determined, \u0026nbsp; the isotope signals (F\u003csub\u003efun\u003c/sub\u003e) could be calculated from the isotopic signal F\u003csub\u003epool\u0026nbsp;\u003c/sub\u003eand biomass m\u003csub\u003epool\u003c/sub\u003e of the pooled samples, using a two pools mass-balance equation: m\u003csub\u003epool\u003c/sub\u003eF\u003csub\u003epool\u003c/sub\u003e = m\u003csub\u003ebac\u003c/sub\u003eF\u003csub\u003ebac\u003c/sub\u003e + m\u003csub\u003efun\u003c/sub\u003eF\u003csub\u003efun\u003c/sub\u003e, where m\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= the biomass ratios and F = the fractional isotopic abundance of bacterivorous and fungivorous nematodes within the two pooled samples.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOther soil arthropods were extracted using a combination of Berlese-Tullgren (dry extraction), underground pitfalls, and flotation methods. Bush-beating was used to sample the small invertebrates living on the plant, while macrofauna (ants and darkling beetles) were collected on sight by hand. Stems of the plant were also peeled under the stereomicroscope to recover small invertebrates living under the leaf layers. All fauna except for nematodes were killed and preserved in 100% ethanol solution. Preservation of faunas in ethanol and formalin can affect their isotopic values but the shift in values was usually less than 1\u0026permil; (F\u0026aacute;bi\u0026aacute;n, 1997; Krab et al., 2012; Sticht et al., 2006).\u0026nbsp;Plant materials (fresh leaves, dead leaves, plant roots, and rhizosheath) were dried at 60\u0026deg;C for 3-5 days. Soil detritus was extracted using a flotation method (3:1 water:soil ratios) then filtered through a fine mesh (6 \u0026micro;m).\u003c/p\u003e\n\u003cp\u003eAbove ground invertebrates were collected by beating the stems and leaves of the grass into a plastic box, then captured with a mouth aspirator modified for immediate preservation in 100% ethanol. We collected most arthropods that did not fly away immediately. We sorted the animals into morphospecies using a stereo-microscope. We selected the morphospecies we estimated to offer enough biomass for stable isotopes analysis and molecular sequencing. One individual of each was selected for genome skimming, either from a cutted leg, or from the whole individual depending on the size. DNA extractions were done using the DNeasy Blood \u0026amp; Tissue Kit (Qiagen, Hilden), Illumina libraries were made using the NEBNext\u0026reg; Ultra\u0026trade; II DNA Library Prep Kit (New England Biolabs, Ipswich), for a 150 bp insert size. Sequencing was done at Novogene UK on a NovaSeq 6000 system (Illumina, San Diego), aiming for 10Gb per library. The sequenced libraries were trimmed with Trimmomatic (v0.39) (Bolger et al., 2014)\u0026nbsp;then assembled with SPAdes (v3.14.1)(Bankevich et al., 2012). The COI-5P marker (658 bp) and the 28S rDNA full gene was searched directly in the scaffolds using Blastn (v2.13.0+). The integrity of the protein coding sequences was verified, and each sequence was first queried on Genbank to check for obvious contaminants. We further confirmed that none of the sequences could be directly assigned to a species using the BOLD identification tool. We then proceeded to a phylogenetic placement. We adapted our method case by case, but the general approach was as follows. For each morphospecies, we subselected the BOLD public database using the lowest taxonomic group we recognized (Araneae, Cicadellidae, Coccoidea, Cucujoidea, Hymenoptera, Psocodea, Pseudoscorpionides and Thysanoptera). For each supra-family taxa selection, we sampled the database allowing from 20 to 50 records for each family (duplicated sequences removed, records randomly selected, and number of maximum records manually tuned to keep the number of OTUs around or below 3000). A rapid phylogenetic placement was performed using MAGUS (Smirnov \u0026amp; Warnow, 2021) for multiple sequence alignments and FastTree2 (Price et al., 2010) for ML tree inference. When the dataset contained less than 400 OTUs, we used Muscle v5 (Edgar, 2022) + Raxml-ng\u0026nbsp;(Kozlov et al., 2019)\u0026nbsp;instead. The trees were visualised using iTOL (Letunic \u0026amp; Bork, 2021). The closest family was selected as a novel filter of the BOLD database, and the sampling process was repeated at genus level. For some taxa, COI-5P did not allow a taxonomic placement. In such cases we retrieved suitable comprehensive phylogenetic datasets based on 28S rDNA and used them to accurately confirm the family of the concerned species. Then again, high resolution placement was done using the COI-5P against the BOLD public database. Once the closest genus could be identified, we searched the literature for previous reports in Namibia. Details for each species are provided in Appendix 1.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStable isotope analysis and statistics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePrior to weighing, all plant and detritus samples were hand-milled manually using a pestle and mortar to ensure homogeneity and transferred into tin capsules. Invertebrates were transferred directly in tin capsules and oven-dried at 60\u0026deg;C for at least 24 hours. \u0026nbsp;Nematodes were weighed in tin capsules with lids to avoid biomass loss from evaporation. Bigger arthropods (tenebrionid and blister beetles) were freeze-dried (Heto PowerDry LL3000; Thermo Fisher Scientific, Waltham, USA)\u0026nbsp;for 48-72 hours. C/N concentrations and stable isotopes were quantified using an elemental analyzer coupled to isotope-ratio mass spectrometer (IRMS) (MAT 251, Finnigan, Bremen, Germany) (Langel \u0026amp; Dyckmans, 2014).\u0026nbsp;Isotope ratios of all samples were reported in conventional \u0026delta;-notation: , where R is the ratio of heavier to lighter isotope. The \u0026delta;\u003csup\u003e\u0026nbsp;\u003c/sup\u003evalues were expressed as per mill (\u0026permil;) or parts per thousand.\u003c/p\u003e\n\u003cp\u003eAll statistical analyses were conducted in R version 3.3.2 (R Core Team, 2020). The R package\u0026nbsp;Stable Isotope Mixing Models (function \u0026ldquo;simmr\u0026rdquo;) was used for the reconstruction of faunal diet\u0026nbsp;(Govan et al., 2023). The mixing models required both the \u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values of consumers as well as likely sources (diet) including corrections (i.e. standard deviations for \u0026delta;\u003csup\u003e13\u003c/sup\u003eC and \u0026delta;\u003csup\u003e15\u003c/sup\u003eN values, enrichment factor for \u003csup\u003e13\u003c/sup\u003eC=0.4\u0026plusmn;1.3\u0026permil; and \u003csup\u003e15\u003c/sup\u003eN=3.4\u0026plusmn;1.0\u0026permil; according to, as well as the % of carbon and nitrogen in diet). Simmr was used to estimate: 1) the contributions of dead leaf, soil detritus, and scale insects\u0026nbsp;to\u0026nbsp;the diets\u0026nbsp;of detritivore species and ii) the contributions of invertebrates from lower trophic levels\u0026nbsp;to\u0026nbsp;the diet of predatory species. Fitting linear models (function \u0026ldquo;lm\u0026rdquo;) was used to determine the correlation between \u0026delta;\u003csup\u003e13\u003c/sup\u003eC of invertebrates and their C/N ratios.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlant Collection Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe plant collection and use were in accordance with all the relevant guidelines\u0026nbsp;provided by the Namibian National Commission on Research, Science, and Technology, as stipulated on the research permit issued with Permit Number RPIV00672022.\u0026nbsp;The plant material used in this study was identified by Dr. Tatiana Miranda and Dr. Martin Ebner, both co-authors of this paper. They have previously published a paper on the same plant \u003cem\u003eS. sabulicola\u003c/em\u003e (Ebner et al., 2011).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData deposition\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eUpon acceptance of the manuscript, the animals DNA sequences will be publicly deposited on BOLD (https://www.boldsystems.org) and voucher specimens will be deposited in the collections of the National Museum of Namibia, Windhoek. All identifiers and accession numbers are to be provided in the final version.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBall, L., \u0026amp; Tzanopoulos, J. (2020). 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Feeding Habits in Soil Nematode Families and Genera--An Outline for Soil Ecologists. \u003cem\u003eJournal of Nematology\u003c/em\u003e, \u003cem\u003e25\u003c/em\u003e(3), 315\u0026ndash;331.\u003c/li\u003e\n\u003cli\u003eYeaton, R. I. (1988). Structure and Function of the Namib Dune Grasslands: Characteristics of the Environmental Gradients and Species Distributions. \u003cem\u003eJournal of Ecology\u003c/em\u003e, \u003cem\u003e76\u003c/em\u003e(3), 744\u0026ndash;758. https://www.jstor.org/stable/2260571\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable\u003c/strong\u003e \u003cstrong\u003e1\u003c/strong\u003e Total carbon, total nitrogen, C/N ratios, and isotopic values of basal resources. Values are reported as mean \u0026plusmn;SD.\u003c/p\u003e\n\u003cdiv\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"964\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003esamples\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003en\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal carbon (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal nitrogen (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eC/N ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026delta;\u003csup\u003e13\u003c/sup\u003eC\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026delta;\u003csup\u003e15\u003c/sup\u003eN\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003col start=\"1\"\u003e\n \u003cli\u003e\u003cem\u003eStipagrostis sabulicola\u003c/em\u003e\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eFresh leaves\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e45.5\u0026plusmn;1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e1.4\u0026plusmn;0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e34.9\u0026plusmn;10.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-15.1\u0026plusmn;0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.2\u0026plusmn;1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eDead leaves\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e43.0\u0026plusmn;3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.5\u0026plusmn;0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e88.5\u0026plusmn;20.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-14.0\u0026plusmn;0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e-1.9\u0026plusmn;1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eDead leaves with fungal infection\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e43.8\u0026plusmn;2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.9\u0026plusmn;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e57.0\u0026plusmn;23.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-14.0\u0026plusmn;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e-0.7\u0026plusmn;2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eRoot\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e45.8\u0026plusmn;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.6\u0026plusmn;0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e71.8\u0026plusmn;10.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-14.1\u0026plusmn;0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.1\u0026plusmn;1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eRhizosheath\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e20.4\u0026plusmn;6.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.5\u0026plusmn;0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e43.5\u0026plusmn;5.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-13.7\u0026plusmn;0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.8\u0026plusmn;0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eSoil detritus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e34.5\u0026plusmn;9.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e0.9\u0026plusmn;0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e38.8\u0026plusmn;11.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-14.3\u0026plusmn;0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e2.0\u0026plusmn;1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003col start=\"2\"\u003e\n \u003cli\u003e\u003cem\u003eAcanthosicyos horridus\u0026nbsp;\u003c/em\u003e\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eLitter (Dead stem)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e43.3\u0026plusmn;3.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e1.6\u0026plusmn;0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e38.2\u0026plusmn;27.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-21.7\u0026plusmn;0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e4.2\u0026plusmn;1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.547717842323653%\" valign=\"top\"\u003e\n \u003cp\u003eSoil detritus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.692946058091286%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e28.8\u0026plusmn;6.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e1.1\u0026plusmn;0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.817427385892117%\" valign=\"bottom\"\u003e\n \u003cp\u003e27.5\u0026plusmn;9.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.751037344398341%\" valign=\"top\"\u003e\n \u003cp\u003e-17.1\u0026plusmn;1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.730290456431534%\" valign=\"top\"\u003e\n \u003cp\u003e3.7\u0026plusmn;0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003cstrong\u003e. \u0026nbsp;\u003c/strong\u003e\u0026delta;13C and ∆15N values found for the aboveground invertebrates\u0026nbsp;of S\u003cem\u003e. sabulicola\u003c/em\u003e FPOs. The feeding habits expected from the known biology of each group were indicated\u003c/p\u003e\n\u003cdiv\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"1011\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTaxon\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003en\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eExpected feeding habit\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSource\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026delta;13C\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e∆15N\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eC/N\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eZygoribatula\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e5 (pooled)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eSaprophilous, fungivorous\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Erdmann et al., 2007)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-14.7\u0026plusmn;0.7\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e0.05\u0026plusmn;0.6\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e5.2\u0026plusmn;0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eDiapsididae\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e5 (pooled)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eSap feeder\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Curtis, 1985a)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-15.7\u0026plusmn;0.8\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e0.9\u0026plusmn;0.6\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e7.7\u0026plusmn;1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eLiposcelis\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eSaprophilous, fungivorous\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Wondale Endshaw \u0026amp; Berhanu Hiruy, 2020)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-20.6\u0026plusmn;3.3\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e2.8\u0026plusmn;1.9\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e9.8\u0026plusmn;4.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eDeltocephalinae\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eSap feeder\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Dmitriev, 2001)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-13.9\u0026plusmn;0.4\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e3.2\u0026plusmn;1.2\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e3.8\u0026plusmn;0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eThysanina\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003ePredator\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Lyle \u0026amp; Haddad, 1938)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-12.8\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e4.0\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e3.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eNanolpium\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003ePredator\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Judson \u0026amp; Heurtault, n.d.)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-18.4\u0026plusmn;2.5\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e5.5\u0026plusmn;0.7\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e5.9\u0026plusmn;1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eCybocephalus\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eScale insect\u0026rsquo;s\u0026nbsp;predator\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Smith, 2022)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-13.5\u0026plusmn;0.2\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e5.9\u0026plusmn;2.8\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e4.6\u0026plusmn;0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eCamponotus detritus\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eMainly honeydew feeder\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Curtis, 1985b)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-15.8\u0026plusmn;1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e6.6\u0026plusmn;0.9\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e4.2\u0026plusmn;0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eOnymacris laeviceps\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eOmnivorous, mainly on plant detritus but also on green plants and dead animals\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Holm \u0026amp; Edney, 1973)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-16.0\u0026plusmn;1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e6.7\u0026plusmn;5.0\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e4.7\u0026plusmn;1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eOnymacris plana\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eOmnivorous, mainly on plant detritus but also on green plants and dead animals\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Holm \u0026amp; Edney, 1973)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-17.2\u0026plusmn;2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e7.2\u0026plusmn;1.8\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e5.0\u0026plusmn;0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003ePhysadesmia globosa\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eNo specific diet, probably omnivorous\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Wharton \u0026amp; Seely, 1982)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-25.2\u0026plusmn;0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e8.5\u0026plusmn;1.6\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e5.3\u0026plusmn;0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003ePredator\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Haddad \u0026amp; Wesołowska, 2011)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-14.1\u0026plusmn;0.3\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e10.9\u0026plusmn;0.9\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e3.5\u0026plusmn;0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eHaplothrips\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eHerbivorous, pollinizer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Wang et al., 2022)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-17.8\u0026plusmn;1.9\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e11.4\u0026plusmn;2.5\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e4.9\u0026plusmn;0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eSibinia\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eHerbivorous\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Henschel et al., 2003)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-21.0\u0026plusmn;1.6\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e13.7\u0026plusmn;1.4\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e4.7\u0026plusmn;0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"14.920948616600791%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eHaltichellinae\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.324110671936759%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.383399209486164%\" valign=\"top\"\u003e\n \u003cp\u003eCarnivorous during larval development then nectar or honeydew feeder.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003e(Heraty et al., 2013)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e-14.0\u0026plusmn;0.3\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e16.7\u0026plusmn;0.4\u0026permil;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.154150197628459%\" valign=\"top\"\u003e\n \u003cp\u003e3.8\u0026plusmn;0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable\u003c/strong\u003e \u003cstrong\u003e3\u003c/strong\u003e Diet estimations of detritivores by stable isotope mixing models (mean % \u0026plusmn;SD). Mean values above 15% are marked by bold letters\u003c/p\u003e\n\u003cdiv\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.32133676092545%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.210796915167094%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eC. detritus\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.596401028277635%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eCybocephalus\u0026nbsp;\u003c/em\u003esp.\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.339331619537274%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eLiposcelis\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.210796915167094%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eO. laeviceps\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.210796915167094%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eO. plana\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.110539845758355%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.45219638242894%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.718346253229974%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.45219638242894%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eDead leaves\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.027\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e0.124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.095\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e0.252\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.422\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.059\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.046\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.026\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.718346253229974%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.079\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.133\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.45219638242894%\" valign=\"top\"\u003e\n \u003cp\u003eFungal-infected dead leaves\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.026\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.668\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.169\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.095\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.023\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.718346253229974%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.799\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.45219638242894%\" valign=\"top\"\u003e\n \u003cp\u003eSoil detritus\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.856\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.179\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.174\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.156\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.009\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.050\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.718346253229974%\" valign=\"top\"\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.027\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.45219638242894%\" valign=\"top\"\u003e\n \u003cp\u003eSoftscale insect\u003c/p\u003e\n \u003cp\u003e(\u003cem\u003eDiaspididae\u0026nbsp;\u003c/em\u003esp.)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.077\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.732\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.420\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.782\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.893\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.072351421188631%\" valign=\"top\"\u003e\n \u003cp\u003e0.050\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.718346253229974%\" valign=\"top\"\u003e\n \u003cp\u003e0.089\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.330749354005168%\" valign=\"top\"\u003e\n \u003cp\u003e0.225\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable\u003c/strong\u003e \u003cstrong\u003e4\u003c/strong\u003e Diet proportions of predators estimated by stable isotope mixing models (mean % \u0026plusmn;SD). Mean values above 15% are marked by bold letters.\u003c/p\u003e\n\u003cdiv\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"718\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.030640668523677%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.194986072423397%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eNanolpium\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.220055710306408%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eThysanina\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.77715877437326%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eSalticinae\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.77715877437326%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eHaltichellinae\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003emean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eLiposcelis\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e0.650\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.086\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.061\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eDiaspididae\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.090\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e0.078\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e0.081\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.116\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.040\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eDeltocephalinae\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.055\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e0.046\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e0.149\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.216\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eZygoribatula\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.119\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e0.085\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.464\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.307\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.078\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.058\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.025\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eSibinia\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.023\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e0.026\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.095\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.058\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eCybocephalus\u003c/em\u003e sp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.037\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e0.029\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e0.190\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.252\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.366\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.166\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.059\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.077\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.001390820584145%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eHaplothrips\u0026nbsp;\u003c/em\u003esp.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.179415855354659%\" valign=\"top\"\u003e\n \u003cp\u003e0.026\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.987482614742698%\" valign=\"top\"\u003e\n \u003cp\u003e0.017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.762169680111265%\" valign=\"top\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.570236439499304%\" valign=\"top\"\u003e\n \u003cp\u003e0.027\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd 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\u003c/table\u003e\n\u003c/div\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-3496857/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3496857/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe Namib Desert is a hyperarid coastal desert where fog is a major moisture source. We hypothesized that the fog-harvesting grass Stipagrostis sabulicola establishes an important ecological niche in the extreme Namib Sand Sea ecosystem, referred to as \"Fog-Plant-Oases (FPO)\". Using a combination of extraction methods, we collected and described the above- and belowground FPO invertebrate communities and inferred their trophic feedings based on stable carbon and nitrogen isotope values. Our findings revealed a complex trophic structure and a unique food web, all of which revolve around a single fog plant as the primary producer. We demonstrated that S. sabulicola serves as the primary energy source for the aboveground food web, encompassing a diverse range of trophic levels. Nevertheless, the distinctive stable isotope values of bacterial- and fungal-feeding nematodes indicated the separation of the aboveground niche, which is primarily sustained by S. sabulicola, from the belowground niche, where wind-blown sediments serve as the main energy source. These findings further accentuate the role of S. sabulicola not only as a primary producer but also as a source of moisture and habitat provider for belowground invertebrates.\u003c/p\u003e\n\u003cp\u003eHuei Ying Gan, Karin Hohberg, and Clément Schneider contributed equally to this work.\u003c/p\u003e","manuscriptTitle":"The Hidden Oases: Unveiling Trophic Dynamics in Namib's Fog Plant Ecosystem","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-11-09 20:01:10","doi":"10.21203/rs.3.rs-3496857/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-01-27T05:20:11+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-01-25T12:05:31+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-12-01T15:01:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"16567d2f-13f6-42f9-adc5-21203f7c4738","date":"2023-11-22T15:16:21+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"e8b3e865-4d1c-4b57-8bfa-ab3d97151efd","date":"2023-11-20T12:31:28+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-11-17T11:31:35+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-11-17T11:25:51+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2023-11-07T11:19:09+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-11-07T11:14:25+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2023-10-27T01:32:53+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c2a2bbd4-a6c1-41ce-9480-f97003b638fb","owner":[],"postedDate":"November 9th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":26059937,"name":"Earth and environmental sciences/Biogeochemistry"},{"id":26059938,"name":"Earth and environmental sciences/Climate sciences"},{"id":26059939,"name":"Earth and environmental sciences/Ecology"},{"id":26059940,"name":"Earth and environmental sciences/Environmental sciences"},{"id":26059941,"name":"Earth and environmental sciences/Hydrology"}],"tags":[],"updatedAt":"2024-06-21T14:49:16+00:00","versionOfRecord":{"articleIdentity":"rs-3496857","link":"https://doi.org/10.1038/s41598-024-61796-8","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2024-06-10 14:49:16","publishedOnDateReadable":"June 10th, 2024"},"versionCreatedAt":"2023-11-09 20:01:10","video":"","vorDoi":"10.1038/s41598-024-61796-8","vorDoiUrl":"https://doi.org/10.1038/s41598-024-61796-8","workflowStages":[]},"version":"v1","identity":"rs-3496857","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3496857","identity":"rs-3496857","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}