Impacts of a super typhoon on coral diversity, substrates and reef fish assemblages on nearshore reefs in Wenchang, northern South China Sea

Impacts of a super typhoon on coral diversity, substrates and reef fish assemblages on nearshore reefs in Wenchang, northern South China Sea | 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 Research Article Impacts of a super typhoon on coral diversity, substrates and reef fish assemblages on nearshore reefs in Wenchang, northern South China Sea Chen Zhang, Zhiqiang Chen, Tuanjie Li, Youqi Wang, Yihua Lv This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8302420/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Typhoons are among the most intense natural disturbances shaping tropical and subtropical coral reefs. Wenchang, on the eastern coast of Hainan Island, lies within a high landfall-frequency zone of the western North Pacific. On 6 September 2024, Super Typhoon Yagi (ID: 2411) made landfall near Wengtian, causing severe impacts on nearby reef habitats. We conducted paired surveys of representative nearshore reefs in August 2024 (pre-event) and September 2024 (post-event) to assess effects on coral cover, reef fish assemblages and benthic substrates. Following the typhoon, live coral cover declined markedly and variability among sites increased. Encrusting and foliose corals contracted sharply, whereas massive corals remained dominant but also decreased slightly. Benthic substrates shifted from being largely covered by macroalgae, sponges and soft corals to rubble–sand dominated states, indicating physical removal of biotic cover and associated habitat damage. Coral species richness decreased from 24.6 to 18.0, and Shannon diversity and evenness declined from 2.45 to 2.13 and from 0.771 to 0.765, respectively, indicating a reduction in α -diversity and fewer co-occurring species rather than an outright collapse of overall diversity structure. Reef fishes showed parallel but distinct responses: total abundance declined substantially (482→289), species richness decreased slightly (13.2→12.0), and dominance structure shifted, with higher Shannon diversity and evenness ( H’ : 1.55→1.92; J’ : 0.651→0.809) and a steeper rank–abundance curve. Dominant corals and fishes both turned over and shifted toward disturbance-tolerant taxa, revealing a multidimensional response characterized by reduced live cover, substrate damage and restructured dominance, but only moderate changes in conventional diversity indices. Together, these results highlight the need for long-term monitoring and targeted restoration to track post-typhoon trajectories and sustain the resilience of nearshore reef ecosystems under a future of potentially more frequent and intense storms. coral reefs typhoon disturbance coral cover biodiversity dominant species Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 1. Introduction Coral reefs are widely recognized as some of the most biodiverse, structurally complex and productive ecosystems on Earth. Despite occupying less than 1% of the global ocean, they provide critical habitat for roughly one quarter of all described marine species (Palomares & Pauly, 2010 ; Porter & Tougas, 2001 ; Jones et al., 2019 ; Fisher et al., 2015 ). Reef frameworks are built and maintained through the continual deposition of calcium carbonate by reef-building scleractinian corals. Massive corals, with robust, thick skeletons, form the primary load-bearing framework; branching and foliose corals rapidly occupy space and increase three-dimensional complexity; and encrusting corals bind rubble and enhance the structural integrity of the reef (Baldock et al., 2014 ; Stoddart, 1969 ). Together, these complementary growth forms create highly complex three-dimensional habitats that provide shelter and breeding grounds for fishes and invertebrates and support multiple ecosystem services, including fisheries production, shoreline protection, biogeochemical cycling, and cultural and tourism values (Wang et al., 2014 ; Costa et al., 2016 ; Moberg & Folke, 1999 ). However, the structural stability and ecological functioning of coral reefs are highly vulnerable to extreme climatic events such as typhoons. Typhoon-driven waves can directly dislodge scleractinians from the substrate or break the skeletons of branching and foliose corals, degrading reef architecture and habitat complexity, thereby reducing biodiversity and weakening coastal protection(White et al., 2013 ; Harris et al., 2018 ). Strong hydrodynamic forcing also resuspends bottom sediments, lowering water clarity and impairing photosynthesis by symbiotic zooxanthellae; resettled sediments may smother coral tissues and cause mortality(Junjie et al., 2014 ; Jones et al., 2019 ). In addition, nutrients released from suspended particles can enrich surface waters, promoting benthic algal overgrowth, triggering phase shifts, and increasing the risks of coral bleaching and disease (Hongo et al., 2012 ; Roff et al., 2015 ; Doropoulos et al., 2014 ). Over longer timescales, such disturbances can alter community structure and decrease biodiversity, thereby diminishing reef contributions to fisheries, shoreline defense, and cultural services. At 16:20 local time on 6 September 2024, Super Typhoon Yagi (international ID 2411; Chinese name Mojie ) made landfall along the coast of Wengtian Town, Wenchang City, Hainan Province, with maximum sustained winds reaching Beaufort force 17 (62 m s⁻¹, ~ 223 km h⁻¹). The event caused severe damage and substantial economic losses in Wenchang and surrounding areas. As a typical extreme weather event, a typhoon can inflict both immediate and far-reaching impacts on coral-reef ecosystems, often manifested as abrupt declines in coral cover, community reassembly and reduced species diversity. However, empirical, region-specific evidence on how such disturbances differentially affect coral growth forms and reef fish diversity remains limited, particularly in the northern South China Sea. To quantitatively assess typhoon-induced disturbance, we conducted paired surveys of representative nearshore reefs in Wenchang immediately before (August 2024) and after (September 2024) the event. We systematically analysed changes in coral assemblages, reef fish assemblages and benthic substrates to elucidate the ecological impacts of Typhoon Yagi on local coral-reef ecosystems and to inform targeted restoration and conservation management in this region. 2. Materials and Methods 2.1 Study Area Wenchang lies on the northeastern coast of Hainan Island, fronting the South China Sea, and is influenced by both the southeasterly monsoon and frequent typhoons, constituting a typical tropical oceanic monsoon climate. Its nearshore waters are characterized by complex hydrodynamics and relatively strong tidal energy, with pronounced inputs from terrigenous runoff and the impacts of coastal development. Compared with the southern reefs around Sanya, Compared with the southern reefs around Sanya, Wenchang's reefs are more discontinuous—occurring mainly as narrow fringing belts or isolated patches in shallow water—and are therefore more vulnerable to typhoon wave forcing and sediment resuspension. In this study, we examined coral and reef-fish communities at five sites (W1-W5) on reefs along Wenchang's eastern coast; site information and locations are provided in Table 1 and Fig. 1 . Table 1 Station information Sites Longitude/E° Latitude/N° W1 110.77 20.04094 W2 111.020641 19.637923 W3 110.979077 19.625904 W4 110.916481 19.57733 W5 110.745959 19.4059 2.2 Data collection and survey methods Surveys followed the Line Intercept Transect (LIT) method (English et al., 1997 ). Trained divers carried underwater video cameras (GoPro 11) and recorded along predefined transects or survey areas in August 2024 (pre-typhoon) and September 2024 (post-typhoon). Survey depth at each station was set according to the local depth range of coral distribution. At each site, five parallel transects of 10 m in length were established at each depth. Depth strata (at least two to three per site) were selected in situ according to the local depth range and vertical distribution of reef-building corals. In the laboratory, transect videos were analyzed for taxonomic identification based on high-resolution footage acquired with GoPro 11 cameras, supported by expert knowledge and regional field guides. Fish sizes were visually estimated by trained observers using reference scales and calibrated field experience. Coral cover and biodiversity metrics were computed from the number of taxonomic units recorded per transect. 2.3 Biodiversity Indices Species richness is one of the most fundamental and widely used biodiversity metrics in ecology; it describes the number of species within a given area without weighting by differences in species abundances (Waide et al., 1999 ). In this study, species diversity at each sampling site was quantified using the Shannon–Wiener index ( H′ ), which jointly accounts for species richness and the evenness of individual distributions among species (Keylock, 2005 ). The index is calculated as: $$\:H’=-\sum\:_{i=1}^{\text{S}}{P}_{i}{ln}\left({P}_{i}\right)$$ where S is the total number of species, and p i is the proportion of individuals of the i- th species in the sample. Pielou's evenness ( J' ) was used to quantify the uniformity of the abundance distribution among species (Jost, 2010 ), and is calculated as: $$\:J’=H’∕{ln}\left(S\right)$$ where H' denotes the Shannon–Wiener diversity index and S is the total number of species in the community. The range of Pielou's evenness J' is 0–1; values approaching 1 indicate a more even distribution of individuals among species, whereas values approaching 0 indicate an uneven distribution dominated by a few species. Differences in Shannon diversity, species richness, and evenness among groups were assessed using Welch's ANOVA, which is appropriate when variances are unequal or sample sizes differ. When the omnibus test was significant, pairwise post hoc comparisons were conducted with the Dunnett T3 procedure. All statistical analyses and visualizations were performed in GraphPad Prism 10.0, with statistical significance set at p < 0.05. 2.4 Dominance index To quantify the relative importance of each species within the community, we used a dominance index ( Y ) that integrates relative abundance and frequency of occurrence. The index is defined as $$\:{Y}_{i}=\frac{{n}_{i}}{N}\times\:{f}_{i}$$ where n i is the abundance (count) of species i , N is the total number of individuals across all species within a transect, and f i is the frequency of occurrence of species i across sampling sites (number of sites where present / total number of sites). Species with Y i >0.02 were classified as dominant (McNaughton, 1970 ). In practice, we first tallied the abundance of each species at every survey site and converted these counts to relative abundance ( n i / N ); we then calculated each species'occurrence frequency ( f i ) across all sites; finally, we obtained the dominance index as the product of these two quantities. This metric captures both numerical superiority and spatial ubiquity, thereby facilitating the identification of dominant species and comparison of community structure before and after the typhoon. All statistical analyses and visualizations were performed in GraphPad Prism 10.0. 3. Results 3.1 Changes in live coral cover and coral growth forms before and after the typhoon As shown in Fig. 2 and Fig. 3 , live coral cover declined after the typhoon and became more spatially dispersed. Total cover decreased from 12.66 ± 4.54% to 9.52 ± 6.97%, with the higher standard deviation indicating greater among-site heterogeneity. In terms of growth forms, massive corals remained dominant in both periods but declined from 9.72 ± 5.38% to 8.29 ± 6.07%, with increased variability, suggesting some resistance to strong disturbance yet a modest downturn. Encrusting and foliose corals showed marked reductions—from 1.20 ± 0.90% and 1.59 ± 2.97% to 0.24 ± 0.24% and 0.23 ± 0.27%, respectively—shifting from broader occurrence to more sporadic presence and indicating greater short-term sensitivity. Branching corals remained at very low cover and contributed little to overall community structure. Collectively, the immediate effects of the typhoon were characterized by a decline in total cover, a slight weakening of the dominant growth form, pronounced contraction of rare/vulnerable forms, and increased among-site variability, reflecting short-term community reassembly and asynchronous spatial responses. 3.2 Changes in coral biodiversity indices before and after the typhoon According to the comparison of substrate composition before and after the typhoon, the structure of benthic substrates on the coral reef changed markedly (Fig. 4 ). Prior to the typhoon, the cover of “others” (including macroalgae, sponges and soft corals, as well as other benthic organisms) was generally high across sites, reaching more than 60% at some locations and exhibiting considerable spatial variability, thus representing the dominant substrate type on the reef. In contrast, the coverage of coral rubble and sand was overall low, with high values occurring only at a few sites. After the typhoon, the mean coverage of both coral rubble and sand increased, whereas the coverage of “others” declined sharply, particularly at sites that had previously been dominated by macroalgae, sponges and soft corals, where this type of substrate decreased substantially. This pattern indicates that the typhoon caused intense disturbance and damage to attached and structurally complex benthic organisms, converting part of the originally biotic substrate cover into coral rubble and unconsolidated sediments, and consequently shifting the reef substrate structure from a state dominated by biotic cover to one characterized by a higher proportion of inorganic substrates. 3.3 Changes in coral biodiversity indices before and after the typhoon Based on the comparison of diversity indices before and after the typhoon, the coral communities exhibited noticeable differences in richness, Shannon diversity, and evenness (Fig. 5 ). Specifically, species richness decreased from an average of approximately 24.6 before the typhoon to 18 after the typhoon, indicating that some species disappeared or were no longer recorded following the typhoon disturbance, and that the overall number of species in the community declined markedly. The Shannon diversity index decreased from 2.45 before the typhoon to 2.13 after the typhoon, suggesting that overall community diversity declined in parallel with the reduction in species richness. By contrast, the evenness index was approximately 0.77 and 0.76 before and after the typhoon, respectively, with only a small change, implying that the typhoon mainly affected community diversity by reducing species richness and total abundance, while its impact on the relative abundance distribution of the remaining species was relatively limited. The Rank–Abundance curve (Fig. 6 ) clearly reveals differences in the community's abundance distribution before and after the typhoon. Overall, the pre-typhoon curve extends farther, indicating a greater number of species and thus higher species richness; by contrast, the post-typhoon curve terminates around the 50th-ranked species, suggesting the loss of some low-abundance species and a reduction in total species number. In terms of curve shape, the leading segment of the pre-typhoon curve is steeper, indicating that a few dominant species accounted for relatively high abundances while rare species were more prevalent. The post-typhoon curve is comparatively flatter, implying that although the number of species declined, differences in abundance among species narrowed and community evenness increased. In sum, the typhoon led to the loss of rare species and an adjustment of dominance patterns, such that species richness decreased while the abundance distribution became more even. 3.4 Changes in dominant coral species, dominance, and rare species before and after the typhoon As shown in Table 2 , the top five dominant coral species changed between periods. Before the typhoon, the most dominant species was Galaxea fascicularis (dominance index = 0.128), followed by Duncanopsammia peltata (0.090), Favites complanata (0.082), Porites lutea (0.081), and Plesiastrea versipora (0.071). After the typhoon, the composition of dominant taxa shifted: G.fascicularis remained first and its dominance increased to 0.173; Porites sp. (0.103) rose to second; Goniopora sp. (0.095) became the new third-ranked dominant taxon; and F.complanata (0.076) and P.versipora (0.044) remained within the top five. Overall, post-typhoon dominance became more concentrated, with some previously dominant species (e.g., D.peltata ) dropping out of the top five and new dominant taxa emerging, indicating that the disturbance altered both the composition and the relative importance of dominant species. 3.5 Changes in reef-fish biodiversity indices before and after the typhoon Based on the comparison of diversity indices, the reef-fish community exhibited different changes in species richness, Shannon diversity, and evenness before and after the typhoon (Fig. 7 ). The mean species richness decreased from 13.2 before the typhoon to 12.0 after the typhoon; the mean Shannon index increased from 1.55 to 1.92; and the mean Pielou's evenness increased from 0.651 to 0.809. Overall, the post-typhoon reef-fish community showed a pattern of slightly reduced richness alongside higher Shannon diversity and evenness. Figure 8 presents a rank–abundance comparison of reef fishes before and after the typhoon (species ordered from highest to lowest abundance). Overall, the post-typhoon curve lies distinctly below the pre-typhoon curve across ranks, and its leading segment (approximately the first 10 ranks) declines more steeply, indicating a general reduction in the abundances of high-ranking species and a greater concentration of dominance. In the mid-to-tail segment (around rank 15 onward), the two curves converge, reflecting assemblages dominated by low-abundance species. The horizontal extents of the curves are similar, indicating comparable numbers of recorded species (37 before the typhoon and 38 after), whereas the total number of individuals declined markedly (482 before vs. 289 after). Thus, Fig. 8 visually depicts a pattern of nearly unchanged species richness coupled with reduced overall abundance and an increased relative contribution of dominant species. 3.6 Changes in dominant reef fish species, dominance, and rare species before and after the typhoon As shown in Table 3 , the dominance rankings of several reef-fish species changed between the two periods. Before the typhoon, the top-ranked species by dominance was Pomacentrus chrysurus (dominance index = 0.118), followed by Pempheris oualensis (0.116), Plectroglyphidodon fasciolatus (0.066), and Chromis fumea (0.039). After the typhoon, the composition of dominant species shifted: P.chrysurus remained first and its dominance increased to 0.274, indicating an enhanced relative status under strong disturbance; P.fasciolatus (0.166) rose to second; Stethojulis bandanensis (0.035) became the new third-ranked dominant taxon; and Labridae sp. (0.021) also became dominant. Overall, post-typhoon dominance became more concentrated, with some previously dominant species (e.g., P.oualensis and C.fumea ) dropping out and new dominant taxa emerging, indicating that the disturbance altered both the composition and the relative importance of dominant species. 4. Discussion 4.1 Effects of typhoon disturbance on coral cover, substrate and spatial patterns Following the typhoon, live coral cover declined overall, with encrusting and foliose growth forms showing the most pronounced reductions, while massive corals exhibited a more moderate decrease and remained the dominant morphological group. In parallel, reef substrate composition was markedly reorganized (Fig. 4 ). Before the typhoon, “others” (macroalgae, sponges, soft corals and other attached benthic organisms) were the primary substrate category and often exceeded 60% cover at some sites, whereas coral rubble and sand were generally less abundant and only locally elevated. After the typhoon, mean cover of coral rubble and sand increased substantially, whereas “others” declined sharply, especially at sites previously dominated by macroalgae, sponges and soft corals. Reef fish abundance responded concordantly: total numbers of individuals and mean abundance per site both decreased between the two surveys, consistent with the loss of structurally complex habitats and the shift towards rubble- and sand-dominated substrates. Typhoons generate large waves and strong winds, producing energetic flows and high shear stresses that are key drivers of enhanced sediment transport (Storlazzi et al., 2011 ). Kench and McLean ( 2004 ) showed that cross-reef flows and sediment transport on the Cocos (Keeling) Islands increased by two orders of magnitude during Tropical Cyclone Graham in December 1991, and subsequent modelling in Hawaiian waters indicated that storm conditions can account for up to 63% of annual sediment flux (Storlazzi et al., 2011 ). Such events therefore provide the physical forcing needed to rapidly remove biotic cover, mobilize unconsolidated material and restructure reef surfaces. At the community level, typhoons often induce abrupt shifts in coral assemblages, disproportionately reducing the abundance of morphologies most vulnerable to wave damage (Adjeroud et al., 2002 ; Connell et al., 2004 ; Fabricius et al., 2008 ; Tanner, 2017 ). In our study, branching and foliose corals, which typically build three-dimensional complexity through rapid growth and space occupation, declined strongly, reflecting their fragile skeletons and high susceptibility to breakage under intense wave energy. Encrusting corals, which stabilize rubble primarily through cementation, almost completely regressed under sediment smothering and strong currents. By contrast, massive corals, with thick skeletons and high structural integrity, retained relatively high cover and showed greater resistance. These functional and morphological differences largely determine sensitivity and response to disturbance, leading to selective loss of fragile growth forms and relative persistence of robust, framework-building taxa. The shift from biotic cover to coral rubble and sand also implies a simplification of habitat structure, with fewer crevices and microhabitats available for reef fishes. This helps explain the observed post-typhoon decline in fish abundance, as species closely associated with structurally complex coral habitats and attached benthic organisms are more likely to decline or relocate. At the same time, between-site variance in cover increased (Fig. 2 ), and substrate configurations became more heterogeneous among sites, indicating that the typhoon not only reduced overall cover but also enhanced small-scale spatial heterogeneity in both communities and substrate structure. Previous studies have similarly reported that disturbance can increase spatial patchiness and among-site variability in benthic communities when its effects are uneven in space (Aronson & Precht, 1995 ; Fuhlendorf et al., 2006 ; Hawkins et al., 2015 ), although strong environmental filtering can also drive homogenization in other contexts (Iacarella et al., 2018 ; Richardson et al., 2018 ). In our case, the increase in spatial heterogeneity suggests that local sedimentation, substrate stability and hydrodynamic conditions were differentially altered among sites, likely leading to non-uniform recovery trajectories. Overall, the typhoon not only reduced total coral cover but, through selective damage and substrate reorganization, reshaped the spatial configuration of benthic habitats, with potentially long-lasting consequences for reef structural and functional stability. 4.2 Apparent stability of diversity indices and hidden vulnerability Analysis of diversity indices showed that coral species richness declined after the typhoon, whereas the Shannon index and evenness changed only slightly. For corals, the Shannon index tended to decrease after the event, whereas for reef fishes it tended to increase; however, both changes were small and not statistically significant, so overall diversity indices appeared broadly stable between the two surveys. This pattern suggests that, although some coral species were lost or no longer detected, the remaining taxa became more evenly distributed in terms of relative abundance, preventing the dominance of a single taxon and keeping aggregate diversity metrics within a narrow range. Such “apparent stability” is consistent with the persistence of resistant groups, notably massive corals, which maintained comparatively high relative abundance and thereby buffered large shifts in community-level indices. However, this apparent stability masks an erosion of the local species pool. The disproportionate loss of rare and disturbance-sensitive growth forms implies reduced functional redundancy and a narrower repertoire of response traits, which may weaken the community's capacity to cope with subsequent or chronic stressors (Mouillot et al., 2014 ; Graham et al., 2011 ). Limited changes in Shannon diversity and evenness therefore do not necessarily indicate a safe or resilient state; rather, they may reflect an intermediate, simplified condition in which diversity metrics lag behind underlying structural and functional degradation. The reef fish assemblage further underscores this hidden vulnerability. Although changes in fish diversity indices were modest, total abundance and mean number of individuals per site declined substantially, and the rank–abundance curve shifted downward with a steeper leading segment. This indicates a contraction in overall abundance accompanied by a relative increase in a few disturbance-tolerant species, while small-bodied and rare species that rely on structurally complex corals and biotically dominated substrates became less common or disappeared. Taken together, the modest shifts in coral diversity indices and the pronounced decline in fish abundance point to a partial decoupling between short-term maintenance of diversity metrics and longer-term loss of species and functions, with consequences that are likely to unfold over extended time scales. 4.3 Turnover in dominant taxa and functional reorganisation Changes in dominant taxa further illuminate the depth of typhoon impacts on reef functioning. Before the typhoon, dominance was distributed among several coral species representing different growth forms, whereas after the event it became concentrated in a smaller subset of resistant, thick-skeleton, predominantly massive taxa. For example, corymbose–massive forms strengthened their dominance, while some previously dominant species dropped out of the top ranks. This pattern is consistent with earlier findings that massive and other robust corals (e.g. Merulinidae, Porites) are generally less affected by storms, whereas assemblages dominated by branching species (e.g. Acropora, Pocillopora, Stylophora) tend to suffer more severe damage (Baird et al., 2018 ). Functionally, this turnover implies a shift from communities that combined rapid framework accretion and high structural complexity, driven in part by branching and foliose corals, towards assemblages dominated by slower-growing but more disturbance-tolerant massive corals. While the latter help maintain basic framework stability and prevent complete structural collapse, their dominance may constrain the recovery of fine-scale structural complexity and associated ecological functions, such as the provision of small refuges and specialised microhabitats for invertebrates and reef fishes. In parallel, post-typhoon dominance patterns among reef fishes became increasingly biased towards species better adapted to rubble–sand substrates, elevated turbidity and simplified habitats, whereas species closely tied to branching and foliose corals retreated from the dominant ranks. Because most reef fishes are mobile and often have longer life spans than their benthic habitat formers, fish assemblages typically exhibit a temporal lag in their response to changes in coral cover and substrate structure. Thus, the declines and compositional shifts observed shortly after the typhoon likely represent an early phase of adjustment, and further divergence between fish and coral assemblages may emerge as habitat degradation or recovery proceeds over longer time scales. Substrate reorganisation and shifts in coral dominance therefore represent two tightly coupled facets of structural–functional adjustment that propagate “bottom-up” to the fish assemblage. In combination, they indicate that the typhoon has pushed the coral reef system towards a new functional state: diversity metrics change only modestly, but the identity of dominant taxa, the nature of the substrate and the distribution of ecological roles have been substantially reorganised. If such disturbance regimes recur or recovery is slow, this reorganisation may alter the division of labour in reef-building processes and energy flow, with potentially long-lasting consequences for the structural and functional stability of the coral reef ecosystem. From a conservation and management perspective, these findings highlight the need to explicitly incorporate extreme events into local reef management in Wenchang. Nearshore reefs that still support structurally complex coral assemblages and biotically rich substrates should be treated as priority areas for protection and post-typhoon monitoring, because they both sustain higher fish abundance and are more sensitive to disturbance. In parallel, reducing chronic land-based stressors—such as sediment and nutrient inputs from coastal development and runoff—could help prevent rubble–sand-dominated states from becoming entrenched and facilitate the natural recovery of branching and foliose corals. At heavily damaged sites, targeted restoration actions, including stabilisation of rubble fields and outplanting of functionally important but disturbance-sensitive taxa, may be warranted. Establishing rapid post-storm assessment protocols and integrating small nearshore reefs into broader regional conservation planning will improve the capacity of managers to track recovery trajectories and maintain the structural and functional diversity of Wenchang's reefs under a future of more frequent and intense typhoons. 5. Conclusion By jointly examining changes in coral cover, substrate composition and reef fish assemblages before and after a major typhoon, this study shows that a single intense event can rapidly and profoundly reorganise coral reef ecosystems. Live coral cover declined markedly, with fragile encrusting, foliose and branching forms experiencing the greatest losses, whereas disturbance-tolerant massive corals retained their relative dominance. Reef substrates shifted from being largely covered by macroalgae, sponges, soft corals and other attached biota to increasingly rubble- and sand-dominated states, reflecting the physical removal of biotic cover and a simplification of habitat structure. Reef fish abundance decreased concurrently, and community composition shifted towards more disturbance-tolerant and habitat-generalist species. At the same time, increased among-site differences in cover and substrate composition indicate that the typhoon not only reduced local biomass and structural complexity, but also enhanced small-scale spatial heterogeneity and the unevenness of recovery trajectories. Overall, our findings show that a single super typhoon can markedly reorganise coral diversity, substrates and reef fish assemblages on nearshore reefs, emphasising the need to incorporate such extreme events into coral reef conservation and restoration planning in increasingly storm-prone oceans. Declarations Institutional Review Board Statement Ethical review and approval were waived for this study due to the fact that all data were obtained through non-invasive ecological field surveys, which did not involve any experimentation on humans or animals. Funding: This work was supported by National Key Research and Development Project of China (no. 2022YFC3106303), National Key Research and Development Program of China (no. 2024YFC-89) Author Contribution Y.L., Z.C.,T.L. and C.Z. conceived the research ideas and designed the methodology; Y.L., Z.C. and T.L. were responsible for data collection and fieldwork; Y.L., Z.C.,T.L. , Y.W. and C.Z.conducted data analysis; Y.L., Z.C.and C.Z. led the writing of the manuscript. All authors have read and agreed to the published version of the manuscript. Data Availability The data associated with the article has been archived in the South China Sea Marine Data Center (https://data.scsio.ac.cn/metaDataPool-detail/1997703865167196160, accessed on 8 December 2025). References Adjeroud M, Augustin D, Galzin R, Salvat B (2002) Natural disturbances and interannual variability of coral reef communities on the outer slope of Tiahura (Moorea, French Polynesia): 1991 to 1997. Mar Ecol Prog Ser 237:121–131 Aronson RB, Precht WF (1995) Landscape patterns of reef coral diversity: a test of the intermediate disturbance hypothesis. J Experimental Marine Biology Ecology 192(1):1–14 Baird AH, Álvarez-Noriega M, Cumbo VR, Connolly SR, Dornelas M, Madin JS (2018) Effects of tropical storms on the demography of reef corals. Mar Ecol Prog Ser 606:29–38 Baldock TE, Karampour H, Sleep R, Vyltla A, Albermani F, Golshani A, Mumby PJ (2014) Resilience of branching and massive corals to wave loading under sea level rise–A coupled computational fluid dynamics-structural analysis. Mar Pollut Bull 86(1–2):91–101 Bessellbrowne P, Jones R, Fisher R (2019) Sediment deposition and coral smothering. PLoS ONE, 14(6), e0216248 Burman SG, Aronson RB, van Woesik R (2012) Biotic homogenization of coral assemblages along the Florida reef tract. Mar Ecol Prog Ser 467:89–96 Connell JH, Hughes TP, Wallace CC, Tanner JE, Harms KE, Kerr AM (2004) A long-term study of competition and diversity of corals. Ecol Monogr 74(2):179–210 Costa MB, Araújo M, Araújo TC, Siegle E (2016) Influence of reef geometry on wave attenuation on a Brazilian coral reef. Geomorphology 253:318–327 Doropoulos C, Roff G, Zupan M, Nestor V, Isechal AL, Mumby PJ (2014) Reef-scale failure of coral settlement following typhoon disturbance and macroalgal bloom in Palau, Western Pacific. Coral Reefs 33(3):613–623 English S, Wilkinson C, Baker V (1997) Survey manual for tropical marine resources. Australian Institute of Marine Science Fabricius KE, De'Ath G, Puotinen ML, Done T, Cooper TF, Burgess SC (2008) Disturbance gradients on inshore and offshore coral reefs caused by a severe tropical cyclone. Limnol Oceanogr 53(2):690–704 Fisher R, O'Leary RA, Low-Choy S, Mengersen K, Knowlton N, Brainard RE, Caley MJ (2015) Species richness on coral reefs and the pursuit of convergent global estimates. Curr Biol 25(4):500–505 Fuhlendorf SD, Harrell WC, Engle DM, Hamilton RG, Davis CA, Leslie Jr DM (2006) Should heterogeneity be the basis for conservation? Grassland bird response to fire and grazing. Ecol Appl 16(5):1706–1716 Graham NAJ, Chabanet P, Evans RD, Jennings S, Letourneur Y, Macneil MA et al (2011) Extinction vulnerability of coral reef fishes. Ecol Lett 14(4):341–348 Harris DL, Rovere A, Casella E, Power H, Canavesio R, Collin A et al (2018) Coral reef structural complexity provides important coastal protection from waves under rising sea levels. Sci Adv 4(2):eaao4350 Hawkins CP, Mykrä H, Oksanen J, Vander Laan JJ (2015) Environmental disturbance can increase beta diversity of stream macroinvertebrate assemblages. Glob Ecol Biogeogr 24(4):483–494 Hongo C, Kawamata H, Goto K (2012) Catastrophic impact of typhoon waves on coral communities in the Ryukyu Islands under global warming. J Geophys Research: Biogeosciences, 117(G2) Iacarella JC, Adamczyk E, Bowen D, Chalifour L, Eger A, Heath W, Baum JK (2018) Anthropogenic disturbance homogenizes seagrass fish communities. Glob Change Biol 24(5):1904–1918 Jones R, Fisher R, Bessell-Browne P (2019) Sediment deposition and coral smothering. PLoS ONE, 14(6), e0216248 Jost L (2010) The relation between evenness and diversity. Diversity 2(2):207–232 Junjie RK, Browne NK, Erftemeijer PLA, Todd PA, Rotjan RD (2014) Impacts of sediments on coral energetics: partitioning the effects of turbidity and settling particles. PLoS ONE, 9(9), e107195 Karp DS, Rominger AJ, Zook J, Ranganathan J, Ehrlich PR, Daily GC (2012) Intensive agriculture erodes β-diversity at large scales. Ecol Lett 15(9):963–970 Kench PS, McLean RF (2004) Hydrodynamics and sediment flux of hoa in an Indian Ocean atoll. Earth Surf Processes Landforms: J Br Geomorphological Res Group 29(8):933–953 Keylock C (2005) Simpson diversity and the Shannon–Wiener index as special cases of a generalized entropy. Oikos 109(1):203–207 McNaughton SJ, Wolf LL (1970) Dominance and the Niche in Ecological Systems: Dominance is an expression of ecological inequalities arising out of different exploitation strategies. Science 167(3915):131–139 Moberg F, Folke C (1999) Ecological goods and services of coral reef ecosystems. Ecol Econ 29(2):215–233 Mouillot D, Villeger S, Parravicini V, Kulbicki M, Arias-Gonzalez JE, Bender M et al (2014) Functional over-redundancy and high functional vulnerability in global fish faunas on tropical reefs. Proc Natl Acad Sci USA 111(38):13757–13762 Palomares MLD, Pauly D (2010) Marine biodiversity in Southeast Asian and adjacent seas: Part 1 Porter JW, Tougas JI (2001) Reef ecosystems: threats to their biodiversity. Encyclopedia Biodivers, 73–95 Richardson LE, Graham NA, Pratchett MS, Eurich JG, Hoey AS (2018) Mass coral bleaching causes biotic homogenization of reef fish assemblages. Glob Change Biol 24(7):3117–3129 Roff G, Chollett I, Doropoulos C, Golbuu Y, Steneck RS, Isechal AL, Mumby PJ (2015) Exposure-driven macroalgal phase shift following catastrophic disturbance on coral reefs. Coral Reefs 34(3):715–725 Socolar JB, Gilroy JJ, Kunin WE, Edwards DP (2016) How should beta-diversity inform biodiversity conservation? Trends Ecol Evol 31(1):67–80 Stoddart DR (1969) Ecology and morphology of recent coral reefs. Biol Rev 44(4):433–498 Storlazzi CD, Elias E, Field ME, Presto MK (2011) Numerical modeling of the impact of sea-level rise on fringing coral reef hydrodynamics and sediment transport. Coral Reefs 30(Suppl 1):83–96 Tanner JE (2017) Multi-decadal analysis reveals contrasting patterns of resilience and decline in coral assemblages. Coral Reefs 36(4):1225–1233 Waide RB, Willig MR, Steiner CF, Mittelbach G, Gough L, Dodson SI, Parmenter R (1999) The relationship between productivity and species richness. Annu Rev Ecol Syst 30(1):257–300 Wang LR, Yu KF, Zhao HT, Zhang QM (2014) Economic Valuation of the Coral Reefs in South China Sea. Trop Geogr 34(1):44–49 White KN, Ohara T, Fujii T, Kawamura I, Reimer JD (2013) Typhoon damage on a shallow mesophotic reef in okinawa, japan. PeerJ 1:e151 Tables Tables 2 and 3 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table23.docx Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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1","display":"","copyAsset":false,"role":"figure","size":243078,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLocation of the study area on Hainan Island and distribution of survey sites\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/06333b1c4ac07d2439a47aba.png"},{"id":100789520,"identity":"8029b7bc-9c7d-4567-b00c-d8732497fd8c","added_by":"auto","created_at":"2026-01-21 12:15:36","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":142491,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChanges in total coral cover and the cover of different coral growth forms before and after the typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/4874364d4bf7b044c1981d95.png"},{"id":100789518,"identity":"e2f0739c-2d64-44e1-91f1-8af57c481673","added_by":"auto","created_at":"2026-01-21 12:15:36","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":770436,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea. Corals with most of their surfaces covered by sediments; b. Coral fragments broken by the typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/674ae834c28c820161f1f21a.png"},{"id":100857771,"identity":"27c311f4-406c-41f9-a17f-5e1c53ff88c0","added_by":"auto","created_at":"2026-01-22 07:22:16","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":83958,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChanges in Reef Substrate Composition Before and After the Typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/22e49be98eab41f686b6938a.png"},{"id":100857755,"identity":"4843d11a-7516-4aaa-b42e-8d399b6a11c0","added_by":"auto","created_at":"2026-01-22 07:21:41","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":91399,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChanges in the diversity indices of coral communities before and after the typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/864932cb6bbca5e67c12e0ca.png"},{"id":100796806,"identity":"771ecaa2-c69d-4e06-81a0-5e3a32ca6a92","added_by":"auto","created_at":"2026-01-21 13:46:04","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":139129,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eRank-Abundance curves of coral communities before and after the typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/66064bf2a1e09344134ff46c.png"},{"id":100789517,"identity":"5a967eeb-4fd8-4a84-87f2-7864acbd4234","added_by":"auto","created_at":"2026-01-21 12:15:36","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":88450,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChanges in the diversity indices of reef fish communities before and after the typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/9ad75e173458c690e076cfde.png"},{"id":100789540,"identity":"71cd8b31-2abc-4c7b-b96c-c00331549b20","added_by":"auto","created_at":"2026-01-21 12:15:36","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":97139,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eRank-Abundance curves of reef fish communities before and after the typhoon\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/6a0e7bd8f4861c80cb3ee751.png"},{"id":101818426,"identity":"b37d195d-2dd2-4976-b475-81cf77581999","added_by":"auto","created_at":"2026-02-04 02:25:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3090875,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/50f4e434-f433-4b07-84c8-330ecd5d35db.pdf"},{"id":100789515,"identity":"c4194cb9-c988-4fff-980d-cef5a26c274e","added_by":"auto","created_at":"2026-01-21 12:15:35","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":2930209,"visible":true,"origin":"","legend":"","description":"","filename":"Table23.docx","url":"https://assets-eu.researchsquare.com/files/rs-8302420/v1/79741f24259e0c1fb463a8c2.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Impacts of a super typhoon on coral diversity, substrates and reef fish assemblages on nearshore reefs in Wenchang, northern South China Sea","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eCoral reefs are widely recognized as some of the most biodiverse, structurally complex and productive ecosystems on Earth. Despite occupying less than 1% of the global ocean, they provide critical habitat for roughly one quarter of all described marine species (Palomares \u0026amp; Pauly, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Porter \u0026amp; Tougas, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2001\u003c/span\u003e; Jones et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Fisher et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Reef frameworks are built and maintained through the continual deposition of calcium carbonate by reef-building scleractinian corals. Massive corals, with robust, thick skeletons, form the primary load-bearing framework; branching and foliose corals rapidly occupy space and increase three-dimensional complexity; and encrusting corals bind rubble and enhance the structural integrity of the reef (Baldock et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Stoddart, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e1969\u003c/span\u003e). Together, these complementary growth forms create highly complex three-dimensional habitats that provide shelter and breeding grounds for fishes and invertebrates and support multiple ecosystem services, including fisheries production, shoreline protection, biogeochemical cycling, and cultural and tourism values (Wang et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Costa et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Moberg \u0026amp; Folke, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e1999\u003c/span\u003e). However, the structural stability and ecological functioning of coral reefs are highly vulnerable to extreme climatic events such as typhoons.\u003c/p\u003e \u003cp\u003eTyphoon-driven waves can directly dislodge scleractinians from the substrate or break the skeletons of branching and foliose corals, degrading reef architecture and habitat complexity, thereby reducing biodiversity and weakening coastal protection(White et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Harris et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Strong hydrodynamic forcing also resuspends bottom sediments, lowering water clarity and impairing photosynthesis by symbiotic zooxanthellae; resettled sediments may smother coral tissues and cause mortality(Junjie et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Jones et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). In addition, nutrients released from suspended particles can enrich surface waters, promoting benthic algal overgrowth, triggering phase shifts, and increasing the risks of coral bleaching and disease (Hongo et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Roff et al., \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Doropoulos et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Over longer timescales, such disturbances can alter community structure and decrease biodiversity, thereby diminishing reef contributions to fisheries, shoreline defense, and cultural services.\u003c/p\u003e \u003cp\u003eAt 16:20 local time on 6 September 2024, Super Typhoon \u003cem\u003eYagi\u003c/em\u003e (international ID 2411; Chinese name \u003cem\u003eMojie\u003c/em\u003e) made landfall along the coast of Wengtian Town, Wenchang City, Hainan Province, with maximum sustained winds reaching Beaufort force 17 (62 m s⁻\u0026sup1;, ~\u0026thinsp;223 km h⁻\u0026sup1;). The event caused severe damage and substantial economic losses in Wenchang and surrounding areas. As a typical extreme weather event, a typhoon can inflict both immediate and far-reaching impacts on coral-reef ecosystems, often manifested as abrupt declines in coral cover, community reassembly and reduced species diversity. However, empirical, region-specific evidence on how such disturbances differentially affect coral growth forms and reef fish diversity remains limited, particularly in the northern South China Sea. To quantitatively assess typhoon-induced disturbance, we conducted paired surveys of representative nearshore reefs in Wenchang immediately before (August 2024) and after (September 2024) the event. We systematically analysed changes in coral assemblages, reef fish assemblages and benthic substrates to elucidate the ecological impacts of Typhoon \u003cem\u003eYagi\u003c/em\u003e on local coral-reef ecosystems and to inform targeted restoration and conservation management in this region.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Study Area\u003c/h2\u003e \u003cp\u003eWenchang lies on the northeastern coast of Hainan Island, fronting the South China Sea, and is influenced by both the southeasterly monsoon and frequent typhoons, constituting a typical tropical oceanic monsoon climate. Its nearshore waters are characterized by complex hydrodynamics and relatively strong tidal energy, with pronounced inputs from terrigenous runoff and the impacts of coastal development. Compared with the southern reefs around Sanya, Compared with the southern reefs around Sanya, Wenchang's reefs are more discontinuous\u0026mdash;occurring mainly as narrow fringing belts or isolated patches in shallow water\u0026mdash;and are therefore more vulnerable to typhoon wave forcing and sediment resuspension. In this study, we examined coral and reef-fish communities at five sites (W1-W5) on reefs along Wenchang's eastern coast; site information and locations are provided in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eStation information\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSites\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLongitude/E\u0026deg;\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLatitude/N\u0026deg;\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e110.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e20.04094\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e111.020641\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19.637923\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e110.979077\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19.625904\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e110.916481\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19.57733\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e110.745959\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19.4059\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Data collection and survey methods\u003c/h2\u003e \u003cp\u003eSurveys followed the Line Intercept Transect (LIT) method (English et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e1997\u003c/span\u003e). Trained divers carried underwater video cameras (GoPro 11) and recorded along predefined transects or survey areas in August 2024 (pre-typhoon) and September 2024 (post-typhoon). Survey depth at each station was set according to the local depth range of coral distribution. At each site, five parallel transects of 10 m in length were established at each depth. Depth strata (at least two to three per site) were selected in situ according to the local depth range and vertical distribution of reef-building corals. In the laboratory, transect videos were analyzed for taxonomic identification based on high-resolution footage acquired with GoPro 11 cameras, supported by expert knowledge and regional field guides. Fish sizes were visually estimated by trained observers using reference scales and calibrated field experience. Coral cover and biodiversity metrics were computed from the number of taxonomic units recorded per transect.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Biodiversity Indices\u003c/h2\u003e \u003cp\u003eSpecies richness is one of the most fundamental and widely used biodiversity metrics in ecology; it describes the number of species within a given area without weighting by differences in species abundances (Waide et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e1999\u003c/span\u003e). In this study, species diversity at each sampling site was quantified using the Shannon\u0026ndash;Wiener index (\u003cem\u003eH\u0026prime;\u003c/em\u003e), which jointly accounts for species richness and the evenness of individual distributions among species (Keylock, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2005\u003c/span\u003e). The index is calculated as:\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:H\u0026rsquo;=-\\sum\\:_{i=1}^{\\text{S}}{P}_{i}{ln}\\left({P}_{i}\\right)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere S is the total number of species, and \u003cem\u003ep\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e is the proportion of individuals of the \u003cem\u003ei-\u003c/em\u003eth species in the sample.\u003c/p\u003e \u003cp\u003ePielou's evenness (\u003cem\u003eJ'\u003c/em\u003e) was used to quantify the uniformity of the abundance distribution among species (Jost, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2010\u003c/span\u003e), and is calculated as:\u003cdiv id=\"Equb\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equb\" name=\"EquationSource\"\u003e\n$$\\:J\u0026rsquo;=H\u0026rsquo;∕{ln}\\left(S\\right)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere \u003cem\u003eH'\u003c/em\u003e denotes the Shannon\u0026ndash;Wiener diversity index and \u003cem\u003eS\u003c/em\u003e is the total number of species in the community. The range of Pielou's evenness \u003cem\u003eJ'\u003c/em\u003e is 0\u0026ndash;1; values approaching 1 indicate a more even distribution of individuals among species, whereas values approaching 0 indicate an uneven distribution dominated by a few species.\u003c/p\u003e \u003cp\u003eDifferences in Shannon diversity, species richness, and evenness among groups were assessed using Welch's ANOVA, which is appropriate when variances are unequal or sample sizes differ. When the omnibus test was significant, pairwise post hoc comparisons were conducted with the Dunnett T3 procedure. All statistical analyses and visualizations were performed in GraphPad Prism 10.0, with statistical significance set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Dominance index\u003c/h2\u003e \u003cp\u003eTo quantify the relative importance of each species within the community, we used a dominance index (\u003cem\u003eY\u003c/em\u003e) that integrates relative abundance and frequency of occurrence. The index is defined as\u003cdiv id=\"Equc\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equc\" name=\"EquationSource\"\u003e\n$$\\:{Y}_{i}=\\frac{{n}_{i}}{N}\\times\\:{f}_{i}$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere \u003cem\u003en\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e is the abundance (count) of species \u003cem\u003ei\u003c/em\u003e, N is the total number of individuals across all species within a transect, and \u003cem\u003ef\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e is the frequency of occurrence of species \u003cem\u003ei\u003c/em\u003e across sampling sites (number of sites where present / total number of sites). Species with \u003cem\u003eY\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e\u0026gt;0.02 were classified as dominant (McNaughton, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e1970\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn practice, we first tallied the abundance of each species at every survey site and converted these counts to relative abundance (\u003cem\u003en\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e/\u003cem\u003eN\u003c/em\u003e); we then calculated each species'occurrence frequency (\u003cem\u003ef\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e) across all sites; finally, we obtained the dominance index as the product of these two quantities. This metric captures both numerical superiority and spatial ubiquity, thereby facilitating the identification of dominant species and comparison of community structure before and after the typhoon. All statistical analyses and visualizations were performed in GraphPad Prism 10.0.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e3.1 Changes in live coral cover and coral growth forms before and after the typhoon\u003c/h2\u003e\n \u003cp\u003eAs shown in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e, live coral cover declined after the typhoon and became more spatially dispersed. Total cover decreased from 12.66\u0026thinsp;\u0026plusmn;\u0026thinsp;4.54% to 9.52\u0026thinsp;\u0026plusmn;\u0026thinsp;6.97%, with the higher standard deviation indicating greater among-site heterogeneity. In terms of growth forms, massive corals remained dominant in both periods but declined from 9.72\u0026thinsp;\u0026plusmn;\u0026thinsp;5.38% to 8.29\u0026thinsp;\u0026plusmn;\u0026thinsp;6.07%, with increased variability, suggesting some resistance to strong disturbance yet a modest downturn. Encrusting and foliose corals showed marked reductions\u0026mdash;from 1.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90% and 1.59\u0026thinsp;\u0026plusmn;\u0026thinsp;2.97% to 0.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.24% and 0.23\u0026thinsp;\u0026plusmn;\u0026thinsp;0.27%, respectively\u0026mdash;shifting from broader occurrence to more sporadic presence and indicating greater short-term sensitivity. Branching corals remained at very low cover and contributed little to overall community structure. Collectively, the immediate effects of the typhoon were characterized by a decline in total cover, a slight weakening of the dominant growth form, pronounced contraction of rare/vulnerable forms, and increased among-site variability, reflecting short-term community reassembly and asynchronous spatial responses.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003e3.2 Changes in coral biodiversity indices before and after the typhoon\u003c/h2\u003e\n \u003cp\u003eAccording to the comparison of substrate composition before and after the typhoon, the structure of benthic substrates on the coral reef changed markedly (Fig. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). Prior to the typhoon, the cover of \u0026ldquo;others\u0026rdquo; (including macroalgae, sponges and soft corals, as well as other benthic organisms) was generally high across sites, reaching more than 60% at some locations and exhibiting considerable spatial variability, thus representing the dominant substrate type on the reef. In contrast, the coverage of coral rubble and sand was overall low, with high values occurring only at a few sites. After the typhoon, the mean coverage of both coral rubble and sand increased, whereas the coverage of \u0026ldquo;others\u0026rdquo; declined sharply, particularly at sites that had previously been dominated by macroalgae, sponges and soft corals, where this type of substrate decreased substantially. This pattern indicates that the typhoon caused intense disturbance and damage to attached and structurally complex benthic organisms, converting part of the originally biotic substrate cover into coral rubble and unconsolidated sediments, and consequently shifting the reef substrate structure from a state dominated by biotic cover to one characterized by a higher proportion of inorganic substrates.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n \u003ch2\u003e3.3 Changes in coral biodiversity indices before and after the typhoon\u003c/h2\u003e\n \u003cp\u003eBased on the comparison of diversity indices before and after the typhoon, the coral communities exhibited noticeable differences in richness, Shannon diversity, and evenness (Fig. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). Specifically, species richness decreased from an average of approximately 24.6 before the typhoon to 18 after the typhoon, indicating that some species disappeared or were no longer recorded following the typhoon disturbance, and that the overall number of species in the community declined markedly. The Shannon diversity index decreased from 2.45 before the typhoon to 2.13 after the typhoon, suggesting that overall community diversity declined in parallel with the reduction in species richness. By contrast, the evenness index was approximately 0.77 and 0.76 before and after the typhoon, respectively, with only a small change, implying that the typhoon mainly affected community diversity by reducing species richness and total abundance, while its impact on the relative abundance distribution of the remaining species was relatively limited.\u003c/p\u003e\n \u003cp\u003eThe Rank\u0026ndash;Abundance curve (Fig. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e) clearly reveals differences in the community\u0026apos;s abundance distribution before and after the typhoon. Overall, the pre-typhoon curve extends farther, indicating a greater number of species and thus higher species richness; by contrast, the post-typhoon curve terminates around the 50th-ranked species, suggesting the loss of some low-abundance species and a reduction in total species number. In terms of curve shape, the leading segment of the pre-typhoon curve is steeper, indicating that a few dominant species accounted for relatively high abundances while rare species were more prevalent. The post-typhoon curve is comparatively flatter, implying that although the number of species declined, differences in abundance among species narrowed and community evenness increased. In sum, the typhoon led to the loss of rare species and an adjustment of dominance patterns, such that species richness decreased while the abundance distribution became more even.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003e3.4 Changes in dominant coral species, dominance, and rare species before and after the typhoon\u003c/h2\u003e\n \u003cp\u003eAs shown in Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, the top five dominant coral species changed between periods. Before the typhoon, the most dominant species was \u003cem\u003eGalaxea fascicularis\u003c/em\u003e (dominance index\u0026thinsp;=\u0026thinsp;0.128), followed by \u003cem\u003eDuncanopsammia peltata\u003c/em\u003e (0.090), \u003cem\u003eFavites complanata\u003c/em\u003e (0.082), Porites lutea (0.081), and \u003cem\u003ePlesiastrea versipora\u003c/em\u003e (0.071). After the typhoon, the composition of dominant taxa shifted: \u003cem\u003eG.fascicularis\u003c/em\u003e remained first and its dominance increased to 0.173; Porites sp. (0.103) rose to second; Goniopora sp. (0.095) became the new third-ranked dominant taxon; and \u003cem\u003eF.complanata\u003c/em\u003e (0.076) and \u003cem\u003eP.versipora\u003c/em\u003e (0.044) remained within the top five. Overall, post-typhoon dominance became more concentrated, with some previously dominant species (e.g., \u003cem\u003eD.peltata\u003c/em\u003e) dropping out of the top five and new dominant taxa emerging, indicating that the disturbance altered both the composition and the relative importance of dominant species.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003e3.5 Changes in reef-fish biodiversity indices before and after the typhoon\u003c/h2\u003e\n \u003cp\u003eBased on the comparison of diversity indices, the reef-fish community exhibited different changes in species richness, Shannon diversity, and evenness before and after the typhoon (Fig. \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e). The mean species richness decreased from 13.2 before the typhoon to 12.0 after the typhoon; the mean Shannon index increased from 1.55 to 1.92; and the mean Pielou\u0026apos;s evenness increased from 0.651 to 0.809. Overall, the post-typhoon reef-fish community showed a pattern of slightly reduced richness alongside higher Shannon diversity and evenness.\u003c/p\u003e\n \u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e presents a rank\u0026ndash;abundance comparison of reef fishes before and after the typhoon (species ordered from highest to lowest abundance). Overall, the post-typhoon curve lies distinctly below the pre-typhoon curve across ranks, and its leading segment (approximately the first 10 ranks) declines more steeply, indicating a general reduction in the abundances of high-ranking species and a greater concentration of dominance. In the mid-to-tail segment (around rank 15 onward), the two curves converge, reflecting assemblages dominated by low-abundance species. The horizontal extents of the curves are similar, indicating comparable numbers of recorded species (37 before the typhoon and 38 after), whereas the total number of individuals declined markedly (482 before vs. 289 after). Thus, Fig. \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e visually depicts a pattern of nearly unchanged species richness coupled with reduced overall abundance and an increased relative contribution of dominant species.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003e3.6 Changes in dominant reef fish species, dominance, and rare species before and after the typhoon\u003c/h2\u003e\n \u003cp\u003eAs shown in Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e, the dominance rankings of several reef-fish species changed between the two periods. Before the typhoon, the top-ranked species by dominance was \u003cem\u003ePomacentrus chrysurus\u003c/em\u003e (dominance index\u0026thinsp;=\u0026thinsp;0.118), followed by \u003cem\u003ePempheris oualensis\u003c/em\u003e (0.116), \u003cem\u003ePlectroglyphidodon fasciolatus\u003c/em\u003e (0.066), and \u003cem\u003eChromis fumea\u003c/em\u003e (0.039). After the typhoon, the composition of dominant species shifted: \u003cem\u003eP.chrysurus\u003c/em\u003e remained first and its dominance increased to 0.274, indicating an enhanced relative status under strong disturbance; \u003cem\u003eP.fasciolatus\u003c/em\u003e (0.166) rose to second; \u003cem\u003eStethojulis bandanensis\u003c/em\u003e (0.035) became the new third-ranked dominant taxon; and \u003cem\u003eLabridae\u003c/em\u003e sp. (0.021) also became dominant. Overall, post-typhoon dominance became more concentrated, with some previously dominant species (e.g., \u003cem\u003eP.oualensis\u003c/em\u003e and \u003cem\u003eC.fumea\u003c/em\u003e) dropping out and new dominant taxa emerging, indicating that the disturbance altered both the composition and the relative importance of dominant species.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e4.1 Effects of typhoon disturbance on coral cover, substrate and spatial patterns\u003c/h2\u003e \u003cp\u003eFollowing the typhoon, live coral cover declined overall, with encrusting and foliose growth forms showing the most pronounced reductions, while massive corals exhibited a more moderate decrease and remained the dominant morphological group. In parallel, reef substrate composition was markedly reorganized (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Before the typhoon, \u0026ldquo;others\u0026rdquo; (macroalgae, sponges, soft corals and other attached benthic organisms) were the primary substrate category and often exceeded 60% cover at some sites, whereas coral rubble and sand were generally less abundant and only locally elevated. After the typhoon, mean cover of coral rubble and sand increased substantially, whereas \u0026ldquo;others\u0026rdquo; declined sharply, especially at sites previously dominated by macroalgae, sponges and soft corals. Reef fish abundance responded concordantly: total numbers of individuals and mean abundance per site both decreased between the two surveys, consistent with the loss of structurally complex habitats and the shift towards rubble- and sand-dominated substrates.\u003c/p\u003e \u003cp\u003eTyphoons generate large waves and strong winds, producing energetic flows and high shear stresses that are key drivers of enhanced sediment transport (Storlazzi et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). Kench and McLean (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2004\u003c/span\u003e) showed that cross-reef flows and sediment transport on the Cocos (Keeling) Islands increased by two orders of magnitude during Tropical Cyclone Graham in December 1991, and subsequent modelling in Hawaiian waters indicated that storm conditions can account for up to 63% of annual sediment flux (Storlazzi et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). Such events therefore provide the physical forcing needed to rapidly remove biotic cover, mobilize unconsolidated material and restructure reef surfaces.\u003c/p\u003e \u003cp\u003eAt the community level, typhoons often induce abrupt shifts in coral assemblages, disproportionately reducing the abundance of morphologies most vulnerable to wave damage (Adjeroud et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2002\u003c/span\u003e; Connell et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Fabricius et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2008\u003c/span\u003e; Tanner, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). In our study, branching and foliose corals, which typically build three-dimensional complexity through rapid growth and space occupation, declined strongly, reflecting their fragile skeletons and high susceptibility to breakage under intense wave energy. Encrusting corals, which stabilize rubble primarily through cementation, almost completely regressed under sediment smothering and strong currents. By contrast, massive corals, with thick skeletons and high structural integrity, retained relatively high cover and showed greater resistance. These functional and morphological differences largely determine sensitivity and response to disturbance, leading to selective loss of fragile growth forms and relative persistence of robust, framework-building taxa.\u003c/p\u003e \u003cp\u003eThe shift from biotic cover to coral rubble and sand also implies a simplification of habitat structure, with fewer crevices and microhabitats available for reef fishes. This helps explain the observed post-typhoon decline in fish abundance, as species closely associated with structurally complex coral habitats and attached benthic organisms are more likely to decline or relocate. At the same time, between-site variance in cover increased (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), and substrate configurations became more heterogeneous among sites, indicating that the typhoon not only reduced overall cover but also enhanced small-scale spatial heterogeneity in both communities and substrate structure. Previous studies have similarly reported that disturbance can increase spatial patchiness and among-site variability in benthic communities when its effects are uneven in space (Aronson \u0026amp; Precht, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e1995\u003c/span\u003e; Fuhlendorf et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; Hawkins et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2015\u003c/span\u003e), although strong environmental filtering can also drive homogenization in other contexts (Iacarella et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Richardson et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). In our case, the increase in spatial heterogeneity suggests that local sedimentation, substrate stability and hydrodynamic conditions were differentially altered among sites, likely leading to non-uniform recovery trajectories. Overall, the typhoon not only reduced total coral cover but, through selective damage and substrate reorganization, reshaped the spatial configuration of benthic habitats, with potentially long-lasting consequences for reef structural and functional stability.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e4.2 Apparent stability of diversity indices and hidden vulnerability\u003c/h2\u003e \u003cp\u003eAnalysis of diversity indices showed that coral species richness declined after the typhoon, whereas the Shannon index and evenness changed only slightly. For corals, the Shannon index tended to decrease after the event, whereas for reef fishes it tended to increase; however, both changes were small and not statistically significant, so overall diversity indices appeared broadly stable between the two surveys. This pattern suggests that, although some coral species were lost or no longer detected, the remaining taxa became more evenly distributed in terms of relative abundance, preventing the dominance of a single taxon and keeping aggregate diversity metrics within a narrow range. Such \u0026ldquo;apparent stability\u0026rdquo; is consistent with the persistence of resistant groups, notably massive corals, which maintained comparatively high relative abundance and thereby buffered large shifts in community-level indices.\u003c/p\u003e \u003cp\u003eHowever, this apparent stability masks an erosion of the local species pool. The disproportionate loss of rare and disturbance-sensitive growth forms implies reduced functional redundancy and a narrower repertoire of response traits, which may weaken the community's capacity to cope with subsequent or chronic stressors (Mouillot et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Graham et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). Limited changes in Shannon diversity and evenness therefore do not necessarily indicate a safe or resilient state; rather, they may reflect an intermediate, simplified condition in which diversity metrics lag behind underlying structural and functional degradation.\u003c/p\u003e \u003cp\u003eThe reef fish assemblage further underscores this hidden vulnerability. Although changes in fish diversity indices were modest, total abundance and mean number of individuals per site declined substantially, and the rank\u0026ndash;abundance curve shifted downward with a steeper leading segment. This indicates a contraction in overall abundance accompanied by a relative increase in a few disturbance-tolerant species, while small-bodied and rare species that rely on structurally complex corals and biotically dominated substrates became less common or disappeared. Taken together, the modest shifts in coral diversity indices and the pronounced decline in fish abundance point to a partial decoupling between short-term maintenance of diversity metrics and longer-term loss of species and functions, with consequences that are likely to unfold over extended time scales.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003e4.3 Turnover in dominant taxa and functional reorganisation\u003c/h2\u003e \u003cp\u003eChanges in dominant taxa further illuminate the depth of typhoon impacts on reef functioning. Before the typhoon, dominance was distributed among several coral species representing different growth forms, whereas after the event it became concentrated in a smaller subset of resistant, thick-skeleton, predominantly massive taxa. For example, corymbose\u0026ndash;massive forms strengthened their dominance, while some previously dominant species dropped out of the top ranks. This pattern is consistent with earlier findings that massive and other robust corals (e.g. Merulinidae, Porites) are generally less affected by storms, whereas assemblages dominated by branching species (e.g. Acropora, Pocillopora, Stylophora) tend to suffer more severe damage (Baird et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eFunctionally, this turnover implies a shift from communities that combined rapid framework accretion and high structural complexity, driven in part by branching and foliose corals, towards assemblages dominated by slower-growing but more disturbance-tolerant massive corals. While the latter help maintain basic framework stability and prevent complete structural collapse, their dominance may constrain the recovery of fine-scale structural complexity and associated ecological functions, such as the provision of small refuges and specialised microhabitats for invertebrates and reef fishes.\u003c/p\u003e \u003cp\u003eIn parallel, post-typhoon dominance patterns among reef fishes became increasingly biased towards species better adapted to rubble\u0026ndash;sand substrates, elevated turbidity and simplified habitats, whereas species closely tied to branching and foliose corals retreated from the dominant ranks. Because most reef fishes are mobile and often have longer life spans than their benthic habitat formers, fish assemblages typically exhibit a temporal lag in their response to changes in coral cover and substrate structure. Thus, the declines and compositional shifts observed shortly after the typhoon likely represent an early phase of adjustment, and further divergence between fish and coral assemblages may emerge as habitat degradation or recovery proceeds over longer time scales.\u003c/p\u003e \u003cp\u003eSubstrate reorganisation and shifts in coral dominance therefore represent two tightly coupled facets of structural\u0026ndash;functional adjustment that propagate \u0026ldquo;bottom-up\u0026rdquo; to the fish assemblage. In combination, they indicate that the typhoon has pushed the coral reef system towards a new functional state: diversity metrics change only modestly, but the identity of dominant taxa, the nature of the substrate and the distribution of ecological roles have been substantially reorganised. If such disturbance regimes recur or recovery is slow, this reorganisation may alter the division of labour in reef-building processes and energy flow, with potentially long-lasting consequences for the structural and functional stability of the coral reef ecosystem.\u003c/p\u003e \u003cp\u003eFrom a conservation and management perspective, these findings highlight the need to explicitly incorporate extreme events into local reef management in Wenchang. Nearshore reefs that still support structurally complex coral assemblages and biotically rich substrates should be treated as priority areas for protection and post-typhoon monitoring, because they both sustain higher fish abundance and are more sensitive to disturbance. In parallel, reducing chronic land-based stressors\u0026mdash;such as sediment and nutrient inputs from coastal development and runoff\u0026mdash;could help prevent rubble\u0026ndash;sand-dominated states from becoming entrenched and facilitate the natural recovery of branching and foliose corals. At heavily damaged sites, targeted restoration actions, including stabilisation of rubble fields and outplanting of functionally important but disturbance-sensitive taxa, may be warranted. Establishing rapid post-storm assessment protocols and integrating small nearshore reefs into broader regional conservation planning will improve the capacity of managers to track recovery trajectories and maintain the structural and functional diversity of Wenchang's reefs under a future of more frequent and intense typhoons.\u003c/p\u003e \u003c/div\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eBy jointly examining changes in coral cover, substrate composition and reef fish assemblages before and after a major typhoon, this study shows that a single intense event can rapidly and profoundly reorganise coral reef ecosystems. Live coral cover declined markedly, with fragile encrusting, foliose and branching forms experiencing the greatest losses, whereas disturbance-tolerant massive corals retained their relative dominance. Reef substrates shifted from being largely covered by macroalgae, sponges, soft corals and other attached biota to increasingly rubble- and sand-dominated states, reflecting the physical removal of biotic cover and a simplification of habitat structure. Reef fish abundance decreased concurrently, and community composition shifted towards more disturbance-tolerant and habitat-generalist species. At the same time, increased among-site differences in cover and substrate composition indicate that the typhoon not only reduced local biomass and structural complexity, but also enhanced small-scale spatial heterogeneity and the unevenness of recovery trajectories. Overall, our findings show that a single super typhoon can markedly reorganise coral diversity, substrates and reef fish assemblages on nearshore reefs, emphasising the need to incorporate such extreme events into coral reef conservation and restoration planning in increasingly storm-prone oceans.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eInstitutional Review Board Statement\u003c/h2\u003e \u003cp\u003eEthical review and approval were waived for this study due to the fact that all data were obtained through non-invasive ecological field surveys, which did not involve any experimentation on humans or animals.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThis work was supported by National Key Research and Development Project of China (no. 2022YFC3106303), National Key Research and Development Program of China (no. 2024YFC-89)\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eY.L., Z.C.,T.L. and C.Z. conceived the research ideas and designed the methodology; Y.L., Z.C. and T.L. were responsible for data collection and fieldwork; Y.L., Z.C.,T.L. , Y.W. and C.Z.conducted data analysis; Y.L., Z.C.and C.Z. led the writing of the manuscript. All authors have read and agreed to the published version of the manuscript.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data associated with the article has been archived in the South China Sea Marine Data Center (https://data.scsio.ac.cn/metaDataPool-detail/1997703865167196160, accessed on 8 December 2025).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAdjeroud M, Augustin D, Galzin R, Salvat B (2002) Natural disturbances and interannual variability of coral reef communities on the outer slope of Tiahura (Moorea, French Polynesia): 1991 to 1997. Mar Ecol Prog Ser 237:121\u0026ndash;131\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAronson RB, Precht WF (1995) Landscape patterns of reef coral diversity: a test of the intermediate disturbance hypothesis. J Experimental Marine Biology Ecology 192(1):1\u0026ndash;14\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaird AH, \u0026Aacute;lvarez-Noriega M, Cumbo VR, Connolly SR, Dornelas M, Madin JS (2018) Effects of tropical storms on the demography of reef corals. Mar Ecol Prog Ser 606:29\u0026ndash;38\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaldock TE, Karampour H, Sleep R, Vyltla A, Albermani F, Golshani A, Mumby PJ (2014) Resilience of branching and massive corals to wave loading under sea level rise\u0026ndash;A coupled computational fluid dynamics-structural analysis. Mar Pollut Bull 86(1\u0026ndash;2):91\u0026ndash;101\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBessellbrowne P, Jones R, Fisher R (2019) Sediment deposition and coral smothering. PLoS ONE, 14(6), e0216248\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBurman SG, Aronson RB, van Woesik R (2012) Biotic homogenization of coral assemblages along the Florida reef tract. Mar Ecol Prog Ser 467:89\u0026ndash;96\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eConnell JH, Hughes TP, Wallace CC, Tanner JE, Harms KE, Kerr AM (2004) A long-term study of competition and diversity of corals. Ecol Monogr 74(2):179\u0026ndash;210\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCosta MB, Ara\u0026uacute;jo M, Ara\u0026uacute;jo TC, Siegle E (2016) Influence of reef geometry on wave attenuation on a Brazilian coral reef. Geomorphology 253:318\u0026ndash;327\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDoropoulos C, Roff G, Zupan M, Nestor V, Isechal AL, Mumby PJ (2014) Reef-scale failure of coral settlement following typhoon disturbance and macroalgal bloom in Palau, Western Pacific. Coral Reefs 33(3):613\u0026ndash;623\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEnglish S, Wilkinson C, Baker V (1997) Survey manual for tropical marine resources. Australian Institute of Marine Science\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFabricius KE, De'Ath G, Puotinen ML, Done T, Cooper TF, Burgess SC (2008) Disturbance gradients on inshore and offshore coral reefs caused by a severe tropical cyclone. Limnol Oceanogr 53(2):690\u0026ndash;704\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFisher R, O'Leary RA, Low-Choy S, Mengersen K, Knowlton N, Brainard RE, Caley MJ (2015) Species richness on coral reefs and the pursuit of convergent global estimates. Curr Biol 25(4):500\u0026ndash;505\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFuhlendorf SD, Harrell WC, Engle DM, Hamilton RG, Davis CA, Leslie Jr DM (2006) Should heterogeneity be the basis for conservation? Grassland bird response to fire and grazing. Ecol Appl 16(5):1706\u0026ndash;1716\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGraham NAJ, Chabanet P, Evans RD, Jennings S, Letourneur Y, Macneil MA et al (2011) Extinction vulnerability of coral reef fishes. Ecol Lett 14(4):341\u0026ndash;348\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHarris DL, Rovere A, Casella E, Power H, Canavesio R, Collin A et al (2018) Coral reef structural complexity provides important coastal protection from waves under rising sea levels. Sci Adv 4(2):eaao4350\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHawkins CP, Mykr\u0026auml; H, Oksanen J, Vander Laan JJ (2015) Environmental disturbance can increase beta diversity of stream macroinvertebrate assemblages. Glob Ecol Biogeogr 24(4):483\u0026ndash;494\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHongo C, Kawamata H, Goto K (2012) Catastrophic impact of typhoon waves on coral communities in the Ryukyu Islands under global warming. J Geophys Research: Biogeosciences, 117(G2)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIacarella JC, Adamczyk E, Bowen D, Chalifour L, Eger A, Heath W, Baum JK (2018) Anthropogenic disturbance homogenizes seagrass fish communities. Glob Change Biol 24(5):1904\u0026ndash;1918\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJones R, Fisher R, Bessell-Browne P (2019) Sediment deposition and coral smothering. PLoS ONE, 14(6), e0216248\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJost L (2010) The relation between evenness and diversity. Diversity 2(2):207\u0026ndash;232\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJunjie RK, Browne NK, Erftemeijer PLA, Todd PA, Rotjan RD (2014) Impacts of sediments on coral energetics: partitioning the effects of turbidity and settling particles. PLoS ONE, 9(9), e107195\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKarp DS, Rominger AJ, Zook J, Ranganathan J, Ehrlich PR, Daily GC (2012) Intensive agriculture erodes β-diversity at large scales. Ecol Lett 15(9):963\u0026ndash;970\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKench PS, McLean RF (2004) Hydrodynamics and sediment flux of hoa in an Indian Ocean atoll. Earth Surf Processes Landforms: J Br Geomorphological Res Group 29(8):933\u0026ndash;953\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKeylock C (2005) Simpson diversity and the Shannon\u0026ndash;Wiener index as special cases of a generalized entropy. Oikos 109(1):203\u0026ndash;207\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMcNaughton SJ, Wolf LL (1970) Dominance and the Niche in Ecological Systems: Dominance is an expression of ecological inequalities arising out of different exploitation strategies. Science 167(3915):131\u0026ndash;139\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoberg F, Folke C (1999) Ecological goods and services of coral reef ecosystems. Ecol Econ 29(2):215\u0026ndash;233\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMouillot D, Villeger S, Parravicini V, Kulbicki M, Arias-Gonzalez JE, Bender M et al (2014) Functional over-redundancy and high functional vulnerability in global fish faunas on tropical reefs. Proc Natl Acad Sci USA 111(38):13757\u0026ndash;13762\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePalomares MLD, Pauly D (2010) Marine biodiversity in Southeast Asian and adjacent seas: Part 1\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePorter JW, Tougas JI (2001) Reef ecosystems: threats to their biodiversity. Encyclopedia Biodivers, 73\u0026ndash;95\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRichardson LE, Graham NA, Pratchett MS, Eurich JG, Hoey AS (2018) Mass coral bleaching causes biotic homogenization of reef fish assemblages. Glob Change Biol 24(7):3117\u0026ndash;3129\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoff G, Chollett I, Doropoulos C, Golbuu Y, Steneck RS, Isechal AL, Mumby PJ (2015) Exposure-driven macroalgal phase shift following catastrophic disturbance on coral reefs. Coral Reefs 34(3):715\u0026ndash;725\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSocolar JB, Gilroy JJ, Kunin WE, Edwards DP (2016) How should beta-diversity inform biodiversity conservation? Trends Ecol Evol 31(1):67\u0026ndash;80\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStoddart DR (1969) Ecology and morphology of recent coral reefs. Biol Rev 44(4):433\u0026ndash;498\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStorlazzi CD, Elias E, Field ME, Presto MK (2011) Numerical modeling of the impact of sea-level rise on fringing coral reef hydrodynamics and sediment transport. Coral Reefs 30(Suppl 1):83\u0026ndash;96\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTanner JE (2017) Multi-decadal analysis reveals contrasting patterns of resilience and decline in coral assemblages. Coral Reefs 36(4):1225\u0026ndash;1233\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWaide RB, Willig MR, Steiner CF, Mittelbach G, Gough L, Dodson SI, Parmenter R (1999) The relationship between productivity and species richness. Annu Rev Ecol Syst 30(1):257\u0026ndash;300\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang LR, Yu KF, Zhao HT, Zhang QM (2014) Economic Valuation of the Coral Reefs in South China Sea. Trop Geogr 34(1):44\u0026ndash;49\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWhite KN, Ohara T, Fujii T, Kawamura I, Reimer JD (2013) Typhoon damage on a shallow mesophotic reef in okinawa, japan. PeerJ 1:e151\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 2 and 3 are available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"coral reefs, typhoon disturbance, coral cover, biodiversity, dominant species","lastPublishedDoi":"10.21203/rs.3.rs-8302420/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8302420/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eTyphoons are among the most intense natural disturbances shaping tropical and subtropical coral reefs. Wenchang, on the eastern coast of Hainan Island, lies within a high landfall-frequency zone of the western North Pacific. On 6 September 2024, Super Typhoon Yagi (ID: 2411) made landfall near Wengtian, causing severe impacts on nearby reef habitats. We conducted paired surveys of representative nearshore reefs in August 2024 (pre-event) and September 2024 (post-event) to assess effects on coral cover, reef fish assemblages and benthic substrates. Following the typhoon, live coral cover declined markedly and variability among sites increased. Encrusting and foliose corals contracted sharply, whereas massive corals remained dominant but also decreased slightly. Benthic substrates shifted from being largely covered by macroalgae, sponges and soft corals to rubble\u0026ndash;sand dominated states, indicating physical removal of biotic cover and associated habitat damage. Coral species richness decreased from 24.6 to 18.0, and Shannon diversity and evenness declined from 2.45 to 2.13 and from 0.771 to 0.765, respectively, indicating a reduction in \u003cem\u003eα\u003c/em\u003e-diversity and fewer co-occurring species rather than an outright collapse of overall diversity structure. Reef fishes showed parallel but distinct responses: total abundance declined substantially (482\u0026rarr;289), species richness decreased slightly (13.2\u0026rarr;12.0), and dominance structure shifted, with higher Shannon diversity and evenness (\u003cem\u003eH\u0026rsquo;\u003c/em\u003e: 1.55\u0026rarr;1.92; \u003cem\u003eJ\u0026rsquo;\u003c/em\u003e: 0.651\u0026rarr;0.809) and a steeper rank\u0026ndash;abundance curve. Dominant corals and fishes both turned over and shifted toward disturbance-tolerant taxa, revealing a multidimensional response characterized by reduced live cover, substrate damage and restructured dominance, but only moderate changes in conventional diversity indices. Together, these results highlight the need for long-term monitoring and targeted restoration to track post-typhoon trajectories and sustain the resilience of nearshore reef ecosystems under a future of potentially more frequent and intense storms.\u003c/p\u003e","manuscriptTitle":"Impacts of a super typhoon on coral diversity, substrates and reef fish assemblages on nearshore reefs in Wenchang, northern South China Sea","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-21 12:15:30","doi":"10.21203/rs.3.rs-8302420/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"438d984b-63a0-447c-8a71-cca5ae59e27a","owner":[],"postedDate":"January 21st, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-04T02:24:02+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-21 12:15:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8302420","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8302420","identity":"rs-8302420","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}