Effects of Environmentally Relevant Microplastic and Nanoplastic Concentrations on Soil Hydro-Physical Properties: A Global Meta-Analysis

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Alghamdi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8629622/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 Aims Microplastics (MPx) and nanoplastics (NPx) are widely distributed in agricultural ecosystems, but their effects on soil physico-hydrological properties remain poorly understood. Methods To better constrain the role of MPx/NPx in soil processes and potential impacts, we conducted a meta-analysis on the effects of MPx/NPx on soil bulk density, porosity, water retention, hydraulic conductivity, and soil organic. Results This study indicates that MNPx decreased soil bulk density (2–6%) and significantly increased porosity (~ 23%), implying that soil compaction was potentially alleviated. The effects of MNPx on water-related properties (e.g., field capacity, hydraulic conductivity) were inconsistent and depended on the polymer types, concentration, and exposure time. MNP was found to be positively associated with soil organic carbon, suggesting that carbon cycling may be altered. The responses of evapotranspiration and aggregate stability to MPx/NPx were variable, indicating context-dependent effects on soil structure. Conclusion In conclusion, our study provided quantitative evidence for predicting the mechanistic effect pathways of MPx in altering soil physic-hydrological properties. Nonetheless, both experimental and modeling studies are required to reveal the ecological impacts of MPx under realistic environmental scenarios. This work also pointed out a significant knowledge gap regarding the long-term and field-scale effects of MPx on soil-water interactions and carbon cycling. Microplastic Nanoplastic Soil physical Soil Hydrology Meta-analysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Introduction Plastic contamination is one of the most serious environmental and societal threats, given its ubiquitous use, long-term persistence in the environment, and negative impacts on biota (Azeem et al. 2022 ). The global plastics production accounted for 368 million tons, of which China and Europe accounted for about 114 and 59 million tons, respectively(Geyer et al. 2017 ). Plastic use was projected to increase from 464 million tons in 2020 to 884 million tons by 2050, resulting in a total stock of plastic in the environment of up to 4725 million tons in 2050 relative to the year 2000 (Dokl et al. 2024 ). Plastic contamination is currently creating a significant global environmental issue due to improper disposal in landfills and unseemly and noncompliant burning. Large-scale production, application, and unethical disposal of plastic waste have resulted in their massive contamination of both terrestrial and aquatic environments (Geyer et al. 2017 ). Microplastics (MPx < 5 mm in size) are one of the most toxic and emerging classes of pollutants in the soil environment (Zhang et al. 2022b ). Initially viewed as predominantly an issue of marine litter, MPx are now known to be both abundant and persistent in terrestrial ecosystems, including agroecosystems. In fact, soils are now thought to be the largest sink of environmental MPx, with an estimated 52% of global MPx emissions(Liu et al. 2024 ; Nizzetto et al. 2016 ; Rillig and Lehmann 2020 ). This soil MPx accumulation is likely due to practices such as plastic mulching, wastewater irrigation, biosolid amendments, atmospheric deposition, and degradation of larger plastic debris [5–7]. It is estimated that more than 50×104 tons of MPx may accumulate in agricultural fields each year (Maddela et al. 2023 ), with up to 7% of the soil mass in some systems (de Souza Machado et al. 2019 ; Tiwari and Sistla 2024 ). These high contamination rates call for a comprehensive evaluation of the full ecological consequences of plastic pollution in soils. In the soil environment, MPx are transported by agricultural activity and biota and can alter nutrient cycling through a variety of biogeochemical pathways, potentially affecting plant growth, productivity, and soil functioning (Azeem et al. 2024 ; Xiang et al. 2025 ; Zhao et al. 2024 ). MPx can be transported through the soil by agricultural practices and biological activity, can alter nutrient cycling via multiple biogeochemical pathways, thereby affecting nutrient availability, plant growth, productivity, and soil functions (Steinmetz et al. 2016 ; Wan et al. 2023 ; Zhou et al. 2024 ). Underlying the delivery of these key soil services are soil hydro-physical characteristics, which are closely linked to the bulk density, porosity, aggregate stability, infiltration capacity, and water retention capacity of the soil (Xu et al. 2024a ). These key soil properties are not only foundational for plant growth and microbial activity but also for regulating water and nutrient dynamics, supporting biogeochemical cycling, and maintaining soil structural integrity (Hillel 2003 ). Disturbances to the soil hydro-physical regime can, thus, have dramatic and undesirable effects on root growth, water flux, gas exchange, and ecosystem productivity (Iqbal et al. 2024 ). Recent evidence has indicated that MPx and NPx can affect all of these fundamental soil processes in ways that can be modulated by the physical and chemical properties of these materials (Li and Xiao 2023 ). Changes in hydro-physical properties may, for example, affect soil aggregation (particle binding), water flow (change porosity and flow path), induce hydrophobicity that impedes water infiltration and retention, and many other processes (de Souza Machado et al. 2018 ; Sajjad et al. 2022 ; Wang et al. 2023 ). MPx have been shown to significantly affect key soil physical properties, including bulk density, aggregation, porosity, and water holding capacity. However, the extent and magnitude of these effects depend highly on the type, shape, and concentration of MPx in the soil (de Souza Machado et al. 2019 ; de Souza Machado et al. 2018 ). These physical alterations of soil structure can, in turn, indirectly affect soil biochemical processes by altering the soil physiochemical, hydraulic, and enzyme activities, organic matter decomposition, nitrification, denitrification, and even microbial diversity and community activities (Lozano et al. 2021b ; Zhao et al. 2021 ). In addition, MPx increases the water repellency of the soil and prevents water infiltration by generating hydrophobic conditions that can directly affect soil biochemical dynamics and C and N contents (Cramer et al. 2023 ; Meng et al. 2022 ; Qi et al. 2020 ). MPx also shifts soil pH and, by extension, the activity of many of these enzymes, which influence soil microbial functions and soil nutrient cycling (Higashida and Takao 1986 ; Inubushi et al. 2022 ; Qiu et al. 2022 ). Once in the soil, MPx migrate and move vertically in the soil profile and are found in a variety of shapes, sizes, and compositions (Jia et al. 2024 ; Yu et al. 2020 ). Several MPx polymers, including polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), high-density polyethylene (HDPE), and biodegradable polylactic acid, have been reported to significantly affect soil physio-hydraulic properties such as soil bulk density, hydraulic characteristics, porosity, and soil nitrogen and C mineralization (Awet et al. 2018 ; Chakraborty et al. 2025 ; Guo et al. 2022 ; Jia et al. 2024 ). However, the findings have been contradictory in that while some reports have indicated decreases in soil bulk density and increases in porosity, others have seen reduced water infiltration and destabilized aggregates with MPx contamination (Boots et al. 2019 ; de Souza Machado et al. 2018 ; Lozano et al. 2021a ). These discrepancies suggest a major gap in our current knowledge, the lack of a systematic assessment of the impact of MPx/NPx on soil hydro-physical dynamics, taking into account a wide diversity of MPx/NPx types, shapes, and sizes, exposure levels, soil types, and soil depth. While the majority of the experimental studies have focused on a limited set of plastic attributes (mostly polymer type or shape) while neglecting how types, particle size, and concentration of MPx can influence its effects on soil hydraulic properties using physicochemical indicators (Iqbal et al. 2024 ; Xiang et al. 2024 ). In addition, the influence of MPx on soil hydraulic properties (water content, hydraulic conductivity, water repellency, among other indicators) has recently emerged as a significant concern in agroecosystems (Meng et al. 2022 ). The vast majority of the available empirical evidence has primarily focused on assessing whether different types, sizes, and concentrations of MPx influence soil physio-hydraulic dynamics (Boots et al. 2019 ; Cramer et al. 2023 ; de Souza Machado et al. 2018 ; Guo et al. 2022 ; Lozano et al. 2021a ). However, recent meta-analyses have sought to understand the effect of MPx on soil physio-chemical properties, C and N cycling, and their consequences for soil biota (Iqbal et al. 2024 ; Xiang et al. 2025 ; Zhang et al. 2022a ) while, the impact of MPx/NPx on soil’s physical and hydraulic behavior has received relatively little systematic attention. In particular, a comprehensive dataset is lacking to quantify the effect of MPx/NPx on key soil physio-hydraulic properties such as bulk density, porosity, saturated hydraulic conductivity, moisture retention and aggregate stability under more realistic environmental conditions. Moreover, MPx/NPx, due to their small size and high potentials to penetrate deeper into the soil matrix, are likely to pose unique risks for altering key hydro-physical properties that have not been well-explored in the context of these synthesis efforts. Understanding how MPx/NPx influence soil hydro-physical functions is a critical step towards predicting their broader ecological consequences. These include potential consequences for crop water use efficiency, erosion vulnerability, nutrient leaching, microbial habitat suitability, and overall food security under plastic-polluted and climate-stressed environments. The emerging view from both field and lab studies is that MPx/NPx, even at environmentally relevant levels, can affect soil structure and water dynamics, but the magnitude, direction, and mechanisms of these effects are highly context-dependent and remain poorly quantified. To address this gap, systematic data syntheses are needed to mechanistically link MPx pollution impacts to key factors modulating their effects on soil hydraulic and physicochemical properties. In this study, we performed a meta-analysis to quantitatively synthesize recent experimental studies to evaluate the impact of MPx/NPx pollution on soil hydro-physical properties, including bulk density, porosity, saturated hydraulic conductivity, moisture retention, and aggregate stability. We hypothesized that the effect of MPx on soil physic-hydraulic properties differed according to (1) fundamental soil characteristics, and (2) plastic-specific factors, including MPx/NPx type, particle size, concentration, exposure medium, and the presence of plants. This study will, therefore, provide a mechanistic and quantitative insight into how MPx/NPx influence the physical structure and hydraulic functioning of soils. It will also build on the existing knowledge by parsing out the roles of environmental moderators and plastic attributes in regulating these interactions. The findings will highlight critical implications for agricultural sustainability under rising plastic pollution and climate variability, and the need to understand these interactions to anticipate risks to soil health, plant productivity, and ecosystem resilience. Methodology Literature search Peer-reviewed Publications from the year 2018-2025 (June 2025) were selected for the meta-analysis study using different databases such as Web of Science, Google Scholar, PubMed, Scopus, PubMed, and ResearchGate. A number of keywords were used for the search including “plastic particles”, “microplastic”, “nanoplastic”, “soil”, “soil bulk density”, “aggregates”, “porosity”, “water stable aggregates”, “soil aggregation”, “soil texture”, “soil organic matter”, “water holding capacity”, “hydraulic conductivity”, “water retention capacity”, “saturated hydraulic conductivity”, “water repellency”, “soil water availability”, “evapotranspiration”, and “soil organic carbon” (Figure 1). We developed and executed a strict search strategy to collect the most relevant, novel, and reliable data sets (Figure S1). As noted above, the initial search returned 1297 research articles, and that group was narrowed to 103 articles (First, reviews, concept papers, opinion articles, and letters lacking primary experimental data were excluded. Second, studies conducted solely in non-soil media or focusing on biodegradation processes, transport mechanisms, or contaminant adsorption were not considered. Due to the limited availability of studies assessing other soil properties beyond hydro-physical and key physic-chemical indicators, papers that did not report data on soil bulk density, porosity, aggregate stability, moisture retention, saturated hydraulic conductivity, or related parameters were excluded from the final dataset) by mandating the following criteria in our search strategy: (i) the study included the application of plastic (MPx or NPx) on agroecosystem (ii) the experiment was conducted under laboratory or field conditions (iii) a control or MPx/NPx-free treatment was included and (iv) the results were supported by appropriate statistical analyses. Only studies that met all four specific criteria were included for meta-analysis. Data extraction Data were extracted from each peer-reviewed study that met the inclusion criteria, including plastic particle size and concentration (Figure S1), soil physic-hydraulic properties studied (Figure S1), and types of plastics (MPx and NPx), encompassing various polymer types such as polyethylene (PE), polystyrene (PS), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyamide (PA), polylactic acid (PLA), fibers, polyether sulfone (PES), polyethylene terephthalate (PET), Polyvinyl chloride (PVC), polypropylene (PP), and MPx with organic amendments (Figure 1). In the current manuscript, the article search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (Figure S1) (Moher et al. 2009). A total of 103 peer-reviewed research articles were included in the meta-analysis (Figure 2), and data were extracted from figures using WebPlotDigitizer 4.8 software (an open-source online tool). Data endpoints In the current meta-analysis classified all data endpoints (i.e., the number of observations within the studies) were classified into three main categories and sixteen sub-categories based on their relevance to soil physic-hydraulic properties. These include indicators of hydraulic behavior such as volumetric water content, hydraulic conductivity, and associated biochemical responses (Figure 2). For instance, if a study investigated multiple treatments of MPx or NPx and reported outcomes related to soil hydraulic parameters, particle size, type, and concentration, each treatment-specific endpoint was included as an independent observation. The classification scheme is illustrated in Figure 3. Each category or sub-category was expressed as a percentage, calculated by dividing the number of affected endpoints by the total number of endpoints within the corresponding main or sub-category. First-order meta-analysis In the current meta-analysis, we used the natural log-transformed response ratio (InRR) method, as described by Hedges et al. (1999) and Gurevitch et al. (2018) to elucidate the impacts of MPx/NPx types, size, and concentration on soil physiological, hydraulic, and biochemical parameters, as illustrated in Figure 3. The following equation was used for calculating the effect size of MPx/NPx. Where X (treat) denotes the mean value of the treatment group, while X (ctrl) represents the mean of the control group. When studies reported only the standard error (SE), then we calculated the standard deviation (SD) using the formula SD = SE √n, where “n” was the number of replicates. The estimated size effect was further converted into a percentage using the following equation. Statistical analysis All statistical analysis and data pre-processing were performed by Microsoft Excel 2021 and OpenMEE software (an open source software) (Viechtbauer and Cheung 2010). The pooled effect of the experiments was calculated using a first-order meta-analysis with 95% confidence intervals (CI = 95%) and illustrated as forest plots. Positive values indicate a beneficial effect on plants, while negative values highlight adverse impacts. All forest plots were generated using GraphPad Prism 8 (version 8.0.2) based on data from OpenMEE software. Results Comprehensive Effect of plastic on soil Figure 4 presents the grand mean effect sizes (± 95% confidence intervals) of plastic contamination (primarily microplastics, MPx, and nanoplastics, NPx) on various soil physico-hydrological and soil organic parameters. The collective results (Fig. 4 and Figure S2) show that MPx/NPx pollution causes a mix of positive and negative shifts in soil properties. Bulk density presents a consistently negative effect size, indicating that MPx exposure significantly decreased soil BD by about 5.45%. As plastics have lower density than mineral soil particles, their presence makes the soil matrix lighter and more porous. This BD reduction under MPx is supported by previous studies; for example, mixing microplastics into loamy sand was found to decrease compaction and increase aeration. Soil aggregation was also adversely affected. Indices of aggregate stability, such as the geometric mean diameter (GWD) of aggregates and total macroaggregate content, showed significant reductions (on the order of 0.4–16%), suggesting that MPx detrimentally impact soil aggregation. Soil porosity (n = 136) presented a positive mean ES (9.42%), meaning that MPx treatment increased the total porosity of soil. In detail, PHB and PET significantly increased total porosity by 47.9–63.5% (Figure S2A). The increase in porosity is directly linked to the lower bulk density of plastic particles and the ability of MPx particles to generate artificial pore spaces by disrupting soil packing. Correspondingly, water retention metrics responded variably. Field capacity (n = 36) shows significantly positive effects (5.65%), suggesting that soils contaminated with plastics tend to retain more water (Figure S2A). Whereas, saturated water content (n = 232) and water absorption capacity (n = 32) showed a negative response (8.4-15.46%) when exposed to different types of MPx (Fig. 4 ). These plastic-induced effects suggest that MPx enhanced the soil’s ability to retain water under saturated or near-saturated conditions, possibly because of the increased porosity and a slower drainage process (Fig. 4 ). Furthermore, the current study revealed that saturated hydraulic conductivity (n = 194) and hydraulic conductivity (n = 186) showed a strong negative response, meaning that MPx contamination seriously affects the water flow behavior in soils (Fig. 4 and S2C). Interestingly, other water-related parameters such as plant-available water (n = 12) and evapotranspiration (n = 44) show positive effects (7.25–17.94%) (Figure S2B). The increase in plant-available water suggests that the incorporation of MPx might change the pore size distribution, which potentially causes an increase in mesopore fractions that contain water plant roots can use (Fig. 4 ). Soil organic carbon (n = 258) also shows a positive ES (6.29%), suggesting that MPx can lead to an increase in measured SOC. This increase may partially be the result of the input of carbon by plastics to the measured pool, as well as indirect MPx effects on the decomposition of organic matter and microbial activities. SOM (n = 168) also shows a positive (1.01%) but highly variable response, with a wide CI, indicating no consistent results across the studies (Fig. 4 and S2D). Impact of plastic (MPx and NPx) size on soil properties The grand mean effect sizes (with 95% CI) of plastic contamination ( 1000 µm, and < 100 nm) on a variety of soil hydro-physical, structural, and carbon-related parameters. On the y-axis, the figure lists soil attributes such as bulk density (n = 220), soil aggregates (n = 40), soil porosity (n = 212), soil moisture (n = 106), field capacity (n = 42), saturated water content (n = 232), saturated hydraulic conductivity (n = 218), hydraulic conductivity (n = 146), water holding capacity (n = 128), MWD (n = 26), GWD (n = 14), water in aggregates (n = 162), plant available water (n = 48), SOC (n = 372) and SOM (n = 132) (Fig. 5 and S3). The findings of the current study revealed that MPx/NPx sizes exhibited a slight negative effect on soil bulk density, suggesting that the presence of plastic particles tends to reduce bulk density. Aggregate indices (aggregates, MWD, and GWD) also show negative effect sizes, indicating a consistent reduction in soil aggregation or aggregate size in response to plastic contamination. In contrast, MPx/NPx sizes significantly increased the soil porosity, suggesting the tendency of plastic contamination to increase the total soil porosity. Field capacity, water-holding capacity, and plant-available water had slight to significant positive responses to MPx/NPx exposure, suggesting the potential for contaminated soils to retain more water or have higher field capacity. However, water aggregates were significantly reduced under plastic contamination with various sizes ( 1000 µm, and < 100 nm). Crucially, plastic contamination strongly impeded soil hydraulic conductivity across particle sizes. Saturated hydraulic conductivity showed a large negative effect size under MPx/NPx presence, and unsaturated hydraulic conductivity was also negatively biased (though not always statistically significant) (Figure S2C). Effect of NPx and MPx concentration on soil hydro physical properties Grand mean effect sizes (with 95% confidence intervals) for a broad set of soil physical, hydraulic, structural, and carbon-related parameters in response to plastic contamination (spanning from nano- to micrometer scale) in soils. On the vertical axis are listed soil attributes such as bulk density (272), water aggregates (34), porosity (182), soil moisture (40), field capacity (28), saturated water content (234), water absorption capacity (28), saturated hydraulic conductivity (196), hydraulic conductivity (192), water holding capacity (118), MWD (32), GWD (18), water aggregates (152), evapotranspiration (34), plant available water (54), SOC (308), and SOM (163) (Fig. 6 ). The numbers in parentheses indicate the number of observations or effect-size records for each parameter. Along the horizontal axis is the effect size scale: zero reflects no overall effect of plastic contamination; negative values denote a decrease in the soil parameter under plastic contamination, while positive values denote an increase. The results outline a multi-faceted pattern of soil responses to plastic contamination. Firstly, bulk density shows a noteworthy negative effect size (the circle is clearly to the left of the zero line), signaling that soils contaminated with plastics tend to have reduced bulk density. In parallel, structural indicators such as MWD and GWD also show negative effect sizes, indicating a decline in aggregate size or stability under plastic contamination. “Water Aggregates (152)” also displays a modest negative effect size, suggesting that the water held or associated with aggregates is reduced. On the contrary, porosity exhibits a positive effect size (circle to the right of zero), meaning that plastic contamination tends to increase the total porosity of soil. Soil Moisture and Field Capacity likewise show positive shifts, indicating that soils with plastic contamination tend to hold more moisture and have higher field capacity (Fig. 6 ). Similarly, saturated water content and water absorption capacity show positive effect sizes, suggesting that the soil’s capacity to fill with water and absorb water is increased in the presence of plastics. Though, and importantly, hydraulic flow parameters behave differently. Both saturated hydraulic conductivity and hydraulic conductivity (unsaturated/other conditions) show strong negative effect sizes, with saturated hydraulic conductivity especially shifted far to the left of zero. This suggests that although soils may hold more water (larger water content, higher field capacity), their capacity to transmit or drain water is markedly impaired when plastics are present (Fig. 6 and S4). Water holding capacity (the ability of soil to retain water accessible to plants) likewise shows a slightly negative effect size. Evapotranspiration and plant-available water show small positive effect sizes, while SOC shows a positive effect size, and SOM again a positive but wide confidence interval (greater uncertainty) (Figure S4). The large CI on SOM also indicates high variability depending on the experimental conditions (Fig. 6 ). Impact of plastic exposure duration on soil hydro physical properties Figure 7 explains the summary of how the duration of plastic exposure in soils influences a range of hydro-physical, structural, and carbon-related soil attributes. On the y-axis various soil parameters including bulk density (n = 276), aggregates (n = 36), porosity (n = 212), soil moisture (n = 120), field capacity (n = 30), saturated water content (n = 216), hydraulic conductivity (n = 50), water holding capacity (n = 108), MWD (n = 26), GWD (n = 18), water aggregates (n = 152), evapotranspiration (n = 38), plant-available water (n = 54), SOC (n = 328) and soil SOM (n = 206) are listed, each with the number of observations in parentheses (Fig. 7 ). The x-axis displays effect sizes, with zero indicating no overall effect of plastic exposure duration; negative values indicate a decline in a given soil parameter with longer exposure, and positive values indicate an increase. From the plotted means and their confidence intervals, several patterns emerge. First, bulk density shows a slightly negative effect size (the point is just to the left of zero), suggesting that as plastic exposure duration increases, bulk density tends to decline, though the effect is moderate (Fig. 7 A). Aggregate metrics (e.g., the “Aggregates” parameter) also trend negatively, indicating that longer plastic exposure may reduce aggregate content or stability in soils. In contrast, porosity shows a small positive effect size, implying that longer exposure to plastics may lead to a modest increase in total pore volume or pore space. Soil moisture shows a slight negative effect, and field capacity likewise appears slightly positive or near zero, but with wide confidence intervals, meaning the evidence is less clear for these parameters under exposure-duration scaling. Saturated water content is very close to zero or slightly positive, but again with limited certainty. Hydraulic conductivity, however, shows a very close to zero (or marginal negative) effect size with a small sample (n = 50), suggesting that longer durations of plastic exposure do not consistently amplify or reduce hydraulic conductivity across studies. Water holding capacity shows a small positive effect, meaning that over time, soils with plastics may hold somewhat more water, accessible or stored (Fig. 7 ). The structural metrics like MWD and GWD display small negative effect sizes, suggesting that longer exposure leads to slight reductions in aggregate size or geometry. Water in aggregates again shows a marginal negative trend. Evapotranspiration shows a moderate positive effect size, indicating that longer exposure to plastics may increase evapotranspiration rates. Plant available water shows a small positive effect size. Importantly, SOC shows a clear positive effect size; longer plastic exposure is associated with increased SOC levels across the dataset. The SOM parameter likewise shows a positive effect but with very wide confidence intervals, reflecting high variability and lower precision (Fig. 7 D). Effect of exposure medium and presence of plants on soil physico-hydrological indicators Figure 8 presents a subgroup meta-analysis illustrating how different exposure media (incubation, pot, field, and column experiments) influence the effects of plastic contamination on key soil physicochemical and hydrological indicators. Each panel shows overall (grand mean) and medium-specific effect sizes with 95% confidence intervals. Figure 8 A shows the impact of plastics on physical properties, which was determined by a meta-analysis of 20 studies. Plastic exposure significantly decreased bulk density (p < 0.001) and soil aggregate stability (p = 0.015), while soil porosity (p < 0.001) increased in general, indicating that plastics made soils looser and more porous. The effects were larger for pot and incubation experiments. Consistent with our analysis, Chen et al. ( 2025 ) and Wang et al. ( 2023 ) reported a lower bulk density in microplastic-amended soils due to the low density of microplastic particles(Chen et al. 2025 ; Wang et al. 2023 ). The reduction of aggregate stability was also consistent with previous studies and may be related to the physical interference of microplastic particles with soil aggregates. Figure 8 B presents the effects of plastics on the water properties of soil. Soil moisture (p = 0.005), field capacity (p < 0.001), and saturated water content (p = 0.018) were slightly higher, while water holding capacity (p = 0.128) and water aggregates (p = 0.676) were not significant under plastic exposure in general, with inconsistent results among different exposure media. Figure S5 includes the effect sizes of different properties (physical, soil water, hydraulic, and organic) with and without plants. The figure uses forest plots to show the effect sizes along with their p-values, which indicate the level of statistical significance of the effect. Each soil property is divided into two sub-categories: with and without plants. The p-values are shown on the right side of the forest plots and help determine if the observed effect is statistically significant or not. The figure shows the effect sizes for different soil properties with and without the presence of plants. In the physical properties category, soil porosity showed a significant effect (I 2 = 99.39%, p < 0.001), indicating that the presence of plants had a strong influence on porosity. The other properties in this category, such as bulk density, soil aggregates, and GWD, showed no significant effect (p > 0.05), but bulk density had a moderate level of variability (I 2 = 55.72%). Discussion Microplastic pollution induces significant changes in soil properties, making soils less compact but more structurally fragile. Our meta-analysis found that bulk density dropped significantly under plastic contamination, consistent with plastics’ low density and the resulting reduction in soil compaction. Studies have shown similar bulk density declines alongside increased soil aeration when microplastics are mixed into soil (Dong et al. 2025 ; Jing et al. 2023 ). Likewise, aggregate stability declined in the presence of plastics, as plastic particles interfere with the natural binding agents (organic matter, fungal hyphae, etc.) that hold soil particles together (Tziourrou and Golia 2024 ). A previous study observed that adding plastic fibers reduced macroaggregate formation and increased microaggregate fractions, illustrating this disruption of aggregation (Liang et al. 2021 ). In summary, microplastics make soil structure looser (lower BD, higher porosity) but also less coherent (weaker aggregation). These structural changes also possess strong effects on soil water dynamics as more total pore space, soils with microplastics can retain more water. We observed higher field capacity and increased soil moisture content in contaminated soils, indicating that microplastics generally favor water retention. However, the concurrent loss of aggregate integrity and pore continuity means that drainage is impeded (Mohammed and Zornberg 2026 ). Correspondingly, saturated hydraulic conductivity dropped sharply in our analysis and water infiltrated much more slowly in plastic-contaminated soil. The same additional pores created by microplastics are often poorly connected, so soils hold more water overall but transmit water downward less efficiently (Wang et al. 2023 ). Similar results found by (Xing et al. 2025 ) where plastics increased soil water retention, they simultaneously decreased infiltration rates. Moreover, (Wang et al. 2024 ) observed that fibrous plastics can clog large soil pores even as they increase small-pore water holding capacity. Microplastics also alters soil biogeochemistry, as evidenced by changes in soil organic carbon as we found a moderate increase in SOC in polluted soils. The increment in SOC fractions is likely due to slower organic matter decomposition as microplastics can suppress microbial activity and enzyme access (Song et al. 2025 ; Yu et al. 2020 ), leading to a buildup of undecomposed material. Microplastics may also create new microhabitats that physically protect organic matter from decay (e.g. by occluding it within plastic-induced pores) (Lehmann et al. 2021 ). Additionally, plastics can also alter measurement of soil organic matter, as (Shi et al. 2022 ) found that microplastic presence raised measured SOC by 21% and microbial biomass up to 17%, but also reduced microbial diversity, indicating a disruption of the soil food web. Thus, higher SOC under contamination likely reflects organic matter accumulating due to impaired breakdown (e.g., via physical protection of organic matter) rather than a true gain in stable humus. Furthermore, the severity of microplastic effects depends on plastic characteristics and exposure duration (Song et al. 2017 ). In our data, smaller microplastic particles (< 1 mm) had more pronounced effects than larger fragments. Fine particles have greater surface area and can blend into soil more thoroughly, so such particles increase soil microporosity but significantly decline BD and hydraulic conductivity (Wang et al. 2023 ). The duration of plastic exposure emerges as an important factor that can accentuate or slightly modify soil responses to MPx/NPx. Over longer time scales, our results indicate that some changes in soil properties become more pronounced for example, bulk density continued to decrease and porosity to increase with extended exposure, hinting at a cumulative structural loosening of soil over time. This could be due to ongoing microplastic fragmentation or gradual reorganization of soil particles around persistent plastics, effectively reshaping the soil matrix year after year (Liu et al. 2021 ). Similarly, the incremental decline in aggregate stability over time suggests that chronic plastic presence might prevent natural processes of aggregate formation or even actively break down existing aggregates through physical abrasion or biophysical interference (e.g. roots and hyphae might be less effective in binding soil that contains plastic fractions) (Fang et al. 2024 ; Liang et al. 2021 ) Our analysis further revealed that plastic effects were generally more pronounced in pot and incubation experiments than in field conditions. In controlled environments, soils are often homogenously mixed with plastics and kept relatively static (no erosion, limited external inputs), so the effects on bulk density, porosity, and other properties manifest clearly. Field studies, however, involve many confounding factors (climate events, bioturbation, heterogeneous distribution of plastics) that can dilute or mask the impact of plastics on measured parameters. For example, we observed that while the direction of change (e.g. reduced bulk density, increased porosity) was consistent, the effect sizes in field studies were typically smaller and sometimes not statistically significant compared to lab studies. This doesn’t mean plastics are benign in the field; rather, it reflects higher variability and possibly adaptive responses in real soil ecosystems. Soil in a pot has no new organic inputs except what researchers add, whereas field soil has continuous litter fall, root growth, and other processes that might compensate for some effects (like aggregation by roots counteracting some microplastic-induced dispersion of particles). Nonetheless, even in field settings, we see significant plastic-induced changes, confirming that the phenomena demonstrated in lab studies do translate to real-world conditions. The presence of plants is another crucial factor as living plants interact with soil plastics in multiple ways like, roots can push plastics through the soil profile, exudates might affect plastic surface chemistry, and plants can modulate soil moisture and structure (Wang et al. 2025 ). Our results with Figure S5 indicated that plants can amplify certain effects of plastics. Notably, the increase in porosity under plastic contamination was even greater when plants were present. This likely arises because roots create biopores and gaps, and in a plastic-laden soil, those root channels plus the microplastic voids together resulted in higher total pore space (Chaudhary et al. 2025 ; Xu et al. 2024b ). In the broader context of ecosystem function, these results suggest that microplastic pollution in soils can interplay with vegetation and land-use in complex ways. Agricultural soils with crops might experience changes in water dynamics due to plastics that could affect irrigation needs or yield (e.g. more water retained near roots but risk of poor drainage). Natural soils with rich biota might buffer some effects (through continuous aggregation processes), but long-term, the persistent presence of plastics still alters the baseline soil condition. Conclusion This meta-analysis indicates that MPx contamination significantly impacted the soil hydro-physical properties. This positive relationship between MPx and most soil hydro-physical parameters was observed. However, some other parameters, such as BD, showed a negative relationship with MPx contamination, and different exposure duration, types of MPs, and concentration also significantly affected the relationships between MPx and soil hydro-physical properties. Although there is a positive correlation between MPx and SOC, although underlying mechanism needs further investigation. Therefore, it is essential to study the long-term effects of MPx on soil structure, water movement, and nutrient cycling, which is a gap in the existing research. Additionally, it is critical to investigate the mechanisms underlying these effects to develop effective soil management practices in MPx-polluted environments. Declarations Acknowledgement The author would like to thank the Ongoing Research Funding program, (ORF-2026-825), King Saud University, Riyadh, Saudi Arabia for funding this investigation. Conflict of interest The authors declare no competing interests Author’s contributions Single Author Consent for publication All authors have read and approved the final version of the manuscript, and everyone has provided their consent for publication of this manuscript. References Awet T, Kohl Y, Meier F, Straskraba S, Grün A-L, Ruf T, Jost C, Drexel R, Tunc E, Emmerling C (2018) Effects of polystyrene nanoparticles on the microbiota and functional diversity of enzymes in soil. 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Journal of Hazardous Materials 461: 132705. doi: https://doi.org/10.1016/j.jhazmat.2023.132705. Supplementary Files Graphicalabstract.docx Supplementaryfile.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. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8629622","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":589900115,"identity":"f4be9150-636c-427e-83db-2e77083e8860","order_by":0,"name":"Abdulaziz G. Alghamdi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4klEQVRIiWNgGAWjYHACNiBm5uHnAXOYSdAi2UOqFgaDM8Rq4e9ffu3BzxxrGeMzx59JMFRYJzbwH36AV4vEjTflhr3b0nnMzvaYSTCcSU9skEgzwG/NjTNpErzbDvOYnedhk2BsOwzUwoBfizxQi+RfoBbjfvZnEoz/gFr4j3/Aq8XgfPsxaZAtBrwNZhKMDUAtDDn4bTG8wcMmLQv0i8SZM8YWCcfSjdskcgrwapE7f/yZ5Ntt1vb8PekPb3yosZbt5z++Aa8WBglkZyQwQKIJP+A//oCgmlEwCkbBKBjhAAA1B0WndPOgygAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-9349-6735","institution":"King Saud University College of Food and Agriculture Sciences","correspondingAuthor":true,"prefix":"","firstName":"Abdulaziz","middleName":"G.","lastName":"Alghamdi","suffix":""}],"badges":[],"createdAt":"2026-01-18 07:02:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8629622/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8629622/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102963084,"identity":"3c9c0af6-62bb-42c6-babc-d493e2207324","added_by":"auto","created_at":"2026-02-19 04:13:22","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":536978,"visible":true,"origin":"","legend":"\u003cp\u003eKeyword co-occurrence network map related to MPx/NPx in soil environments, showing clustered research themes such as soil contamination, water indicators, hydraulic parameters, and environmental impacts. Node size highlights keyword frequency, while line thickness reflects co-occurrence strength. (B) Top 25 keywords with the strongest citation bursts from 2016 to 2025, highlighting temporal trends and emerging topics in MPx/NPx research within soil systems. Red bars indicate periods of high citation intensity.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/16b9830e1974580a2b2751cf.png"},{"id":102963279,"identity":"e0abf601-b6dc-4429-96f7-a6ad807d956a","added_by":"auto","created_at":"2026-02-19 04:15:08","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":334604,"visible":true,"origin":"","legend":"\u003cp\u003eOverview of the meta-analysis workflow assessing the impact of MPx/NPx on soil physio-biochemical and hydraulic properties. The figure illustrates the objective, keyword-based literature search strategy, screening process, and final data analysis.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/bb8313a726b13c48081c3eb5.png"},{"id":102860121,"identity":"033b83e0-1b9c-4a42-bb70-c6b6c9ad3ce6","added_by":"auto","created_at":"2026-02-17 15:59:48","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":702718,"visible":true,"origin":"","legend":"\u003cp\u003eMeta-analysis categories and sub-categories about MPx/NPx.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/56cf63109535935b89c9e274.png"},{"id":102860123,"identity":"10d58c48-6db1-4c75-8576-2f1a4cd050c7","added_by":"auto","created_at":"2026-02-17 15:59:49","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":262917,"visible":true,"origin":"","legend":"\u003cp\u003eForest plot showing the grand mean (overall combined) effect sizes (±95% CI) of MPx contamination on soil hydro-physical and structural properties. The vertical dashed line highlights the null effect (zero). Circles represent mean effect sizes, with the values in parentheses indicating the number of observations.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/e8606b939727a99b52b25c6e.png"},{"id":102860119,"identity":"3d7c1320-fb07-45bd-a791-ec0eb358b862","added_by":"auto","created_at":"2026-02-17 15:59:48","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":245629,"visible":true,"origin":"","legend":"\u003cp\u003eForest plot on the grand mean (overall combined) impact of plastic size on soil physio-hydrological indicators. Circular markers indicate mean effect sizes, and whiskers represent 95% confidence intervals. The black vertical line indicates no change in parameters. Values in brackets (n) are the sample sizes. Groups with significant differences (p \u0026lt; 0.05) are marked.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/67afe32c98f2bfeddc15208a.png"},{"id":102860124,"identity":"00d051bf-6038-46fa-b9a9-423cc3660579","added_by":"auto","created_at":"2026-02-17 15:59:49","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":261619,"visible":true,"origin":"","legend":"\u003cp\u003eForest plot of the grand mean (overall combined) of MPx/NPx concentrations on soil indicators. Error bars represent the confidence intervals about the mean. The vertical dotted line indicates zero effect (no response). Positive values indicate increases, negative values indicate decreases. Numbers in left-side brackets indicate the number of observations.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/c6e202b97253c69ab0c11113.png"},{"id":102963455,"identity":"a9d5c1da-1e85-466b-97d0-388fb0516e22","added_by":"auto","created_at":"2026-02-19 04:18:00","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":415052,"visible":true,"origin":"","legend":"\u003cp\u003eGrand mean effects (overall combined) of MPx/NPx exposure duration on soil parameters. (A) soil physical properties, (B) soil water content indicators, (C) soil hydraulic properties, and (D) soil organic indicators. Error bars represent the confidence intervals about the mean. The vertical dotted line indicates zero effect (no response). Positive values indicate increases, negative values indicate decreases. Numbers in left-side brackets indicate the number of observations.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/b396b7a32677c06c118e1bb4.png"},{"id":102860117,"identity":"1f94ffec-dc1d-436e-a06c-41e369e12994","added_by":"auto","created_at":"2026-02-17 15:59:48","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":378980,"visible":true,"origin":"","legend":"\u003cp\u003eSubgroup meta-analysis of effect sizes of plastic exposure in different experimental media (incubation, pot, field, and column) on soil physicochemical and hydrological indices. (A) Bulk density, soil aggregates, and soil porosity; (B) soil moisture, field capacity, saturated water content, water holding capacity, and water aggregates; (C) saturated hydraulic conductivity and hydraulic conductivity; and (D) soil organic carbon (SOC) and soil organic matter (SOM). Open dots denote mean effect sizes with 95% confidence intervals, and the dashed vertical line represents the grand mean.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/a4ce8499eb30bacb0d67c12b.png"},{"id":102967052,"identity":"35883004-8302-44c5-b046-28a9a21c3f3b","added_by":"auto","created_at":"2026-02-19 04:39:47","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":374250,"visible":true,"origin":"","legend":"\u003cp\u003eFlowcharts highlight the interconnection between microplastics (MPx) sources and the potential impact they could have on soil properties. Furthermore, the impact has been categorized into three groups. They are the effects associated with bulk density and aggregate stability (MWD, GWD), water holding capacity and organic matter (SOM, SOC), and the impact of MPx/NPx on soil properties in the presence or absence of plants.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/fa015df1cb4e311024999aee.png"},{"id":107481427,"identity":"ccd2d2f8-2dbb-4f2d-922c-1bfe1dca7786","added_by":"auto","created_at":"2026-04-22 02:17:49","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3421625,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/23b01756-fbdb-4a26-a243-33f4a07ad810.pdf"},{"id":102860125,"identity":"059c8085-b950-40b4-8a94-30f213acfa1e","added_by":"auto","created_at":"2026-02-17 15:59:49","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":212236,"visible":true,"origin":"","legend":"","description":"","filename":"Graphicalabstract.docx","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/c14e8724ada9a745a41d6d08.docx"},{"id":102860122,"identity":"938b0e1a-f6d1-4356-b413-3fc7059663c0","added_by":"auto","created_at":"2026-02-17 15:59:48","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":1668548,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementaryfile.docx","url":"https://assets-eu.researchsquare.com/files/rs-8629622/v1/e128c8b3872fc75cfc857271.docx"}],"financialInterests":"","formattedTitle":"Effects of Environmentally Relevant Microplastic and Nanoplastic Concentrations on Soil Hydro-Physical Properties: A Global Meta-Analysis","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePlastic contamination is one of the most serious environmental and societal threats, given its ubiquitous use, long-term persistence in the environment, and negative impacts on biota (Azeem et al. \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). The global plastics production accounted for 368\u0026nbsp;million tons, of which China and Europe accounted for about 114 and 59\u0026nbsp;million tons, respectively(Geyer et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Plastic use was projected to increase from 464\u0026nbsp;million tons in 2020 to 884\u0026nbsp;million tons by 2050, resulting in a total stock of plastic in the environment of up to 4725\u0026nbsp;million tons in 2050 relative to the year 2000 (Dokl et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Plastic contamination is currently creating a significant global environmental issue due to improper disposal in landfills and unseemly and noncompliant burning. Large-scale production, application, and unethical disposal of plastic waste have resulted in their massive contamination of both terrestrial and aquatic environments (Geyer et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Microplastics (MPx\u0026thinsp;\u0026lt;\u0026thinsp;5 mm in size) are one of the most toxic and emerging classes of pollutants in the soil environment (Zhang et al. \u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e2022b\u003c/span\u003e). Initially viewed as predominantly an issue of marine litter, MPx are now known to be both abundant and persistent in terrestrial ecosystems, including agroecosystems. In fact, soils are now thought to be the largest sink of environmental MPx, with an estimated 52% of global MPx emissions(Liu et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Nizzetto et al. \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Rillig and Lehmann \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). This soil MPx accumulation is likely due to practices such as plastic mulching, wastewater irrigation, biosolid amendments, atmospheric deposition, and degradation of larger plastic debris [5\u0026ndash;7]. It is estimated that more than 50\u0026times;104 tons of MPx may accumulate in agricultural fields each year (Maddela et al. \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), with up to 7% of the soil mass in some systems (de Souza Machado et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Tiwari and Sistla \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). These high contamination rates call for a comprehensive evaluation of the full ecological consequences of plastic pollution in soils. In the soil environment, MPx are transported by agricultural activity and biota and can alter nutrient cycling through a variety of biogeochemical pathways, potentially affecting plant growth, productivity, and soil functioning (Azeem et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Xiang et al. \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Zhao et al. \u003cspan citationid=\"CR60\" class=\"CitationRef\"\u003e2024\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eMPx can be transported through the soil by agricultural practices and biological activity, can alter nutrient cycling via multiple biogeochemical pathways, thereby affecting nutrient availability, plant growth, productivity, and soil functions (Steinmetz et al. \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Wan et al. \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Zhou et al. \u003cspan citationid=\"CR61\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Underlying the delivery of these key soil services are soil hydro-physical characteristics, which are closely linked to the bulk density, porosity, aggregate stability, infiltration capacity, and water retention capacity of the soil (Xu et al. \u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e2024a\u003c/span\u003e). These key soil properties are not only foundational for plant growth and microbial activity but also for regulating water and nutrient dynamics, supporting biogeochemical cycling, and maintaining soil structural integrity (Hillel \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2003\u003c/span\u003e). Disturbances to the soil hydro-physical regime can, thus, have dramatic and undesirable effects on root growth, water flux, gas exchange, and ecosystem productivity (Iqbal et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Recent evidence has indicated that MPx and NPx can affect all of these fundamental soil processes in ways that can be modulated by the physical and chemical properties of these materials (Li and Xiao \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Changes in hydro-physical properties may, for example, affect soil aggregation (particle binding), water flow (change porosity and flow path), induce hydrophobicity that impedes water infiltration and retention, and many other processes (de Souza Machado et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Sajjad et al. \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Wang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eMPx have been shown to significantly affect key soil physical properties, including bulk density, aggregation, porosity, and water holding capacity. However, the extent and magnitude of these effects depend highly on the type, shape, and concentration of MPx in the soil (de Souza Machado et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; de Souza Machado et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). These physical alterations of soil structure can, in turn, indirectly affect soil biochemical processes by altering the soil physiochemical, hydraulic, and enzyme activities, organic matter decomposition, nitrification, denitrification, and even microbial diversity and community activities (Lozano et al. \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e; Zhao et al. \u003cspan citationid=\"CR59\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). In addition, MPx increases the water repellency of the soil and prevents water infiltration by generating hydrophobic conditions that can directly affect soil biochemical dynamics and C and N contents (Cramer et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Meng et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Qi et al. \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). MPx also shifts soil pH and, by extension, the activity of many of these enzymes, which influence soil microbial functions and soil nutrient cycling (Higashida and Takao \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e1986\u003c/span\u003e; Inubushi et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Qiu et al. \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Once in the soil, MPx migrate and move vertically in the soil profile and are found in a variety of shapes, sizes, and compositions (Jia et al. \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Yu et al. \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Several MPx polymers, including polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), high-density polyethylene (HDPE), and biodegradable polylactic acid, have been reported to significantly affect soil physio-hydraulic properties such as soil bulk density, hydraulic characteristics, porosity, and soil nitrogen and C mineralization (Awet et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Chakraborty et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Guo et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Jia et al. \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). However, the findings have been contradictory in that while some reports have indicated decreases in soil bulk density and increases in porosity, others have seen reduced water infiltration and destabilized aggregates with MPx contamination (Boots et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; de Souza Machado et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Lozano et al. \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2021a\u003c/span\u003e). These discrepancies suggest a major gap in our current knowledge, the lack of a systematic assessment of the impact of MPx/NPx on soil hydro-physical dynamics, taking into account a wide diversity of MPx/NPx types, shapes, and sizes, exposure levels, soil types, and soil depth. While the majority of the experimental studies have focused on a limited set of plastic attributes (mostly polymer type or shape) while neglecting how types, particle size, and concentration of MPx can influence its effects on soil hydraulic properties using physicochemical indicators (Iqbal et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Xiang et al. \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). In addition, the influence of MPx on soil hydraulic properties (water content, hydraulic conductivity, water repellency, among other indicators) has recently emerged as a significant concern in agroecosystems (Meng et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). The vast majority of the available empirical evidence has primarily focused on assessing whether different types, sizes, and concentrations of MPx influence soil physio-hydraulic dynamics (Boots et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Cramer et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; de Souza Machado et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Guo et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Lozano et al. \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2021a\u003c/span\u003e). However, recent meta-analyses have sought to understand the effect of MPx on soil physio-chemical properties, C and N cycling, and their consequences for soil biota (Iqbal et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Xiang et al. \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Zhang et al. \u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e2022a\u003c/span\u003e) while, the impact of MPx/NPx on soil\u0026rsquo;s physical and hydraulic behavior has received relatively little systematic attention. In particular, a comprehensive dataset is lacking to quantify the effect of MPx/NPx on key soil physio-hydraulic properties such as bulk density, porosity, saturated hydraulic conductivity, moisture retention and aggregate stability under more realistic environmental conditions. Moreover, MPx/NPx, due to their small size and high potentials to penetrate deeper into the soil matrix, are likely to pose unique risks for altering key hydro-physical properties that have not been well-explored in the context of these synthesis efforts.\u003c/p\u003e \u003cp\u003eUnderstanding how MPx/NPx influence soil hydro-physical functions is a critical step towards predicting their broader ecological consequences. These include potential consequences for crop water use efficiency, erosion vulnerability, nutrient leaching, microbial habitat suitability, and overall food security under plastic-polluted and climate-stressed environments. The emerging view from both field and lab studies is that MPx/NPx, even at environmentally relevant levels, can affect soil structure and water dynamics, but the magnitude, direction, and mechanisms of these effects are highly context-dependent and remain poorly quantified. To address this gap, systematic data syntheses are needed to mechanistically link MPx pollution impacts to key factors modulating their effects on soil hydraulic and physicochemical properties.\u003c/p\u003e \u003cp\u003eIn this study, we performed a meta-analysis to quantitatively synthesize recent experimental studies to evaluate the impact of MPx/NPx pollution on soil hydro-physical properties, including bulk density, porosity, saturated hydraulic conductivity, moisture retention, and aggregate stability. We hypothesized that the effect of MPx on soil physic-hydraulic properties differed according to (1) fundamental soil characteristics, and (2) plastic-specific factors, including MPx/NPx type, particle size, concentration, exposure medium, and the presence of plants. This study will, therefore, provide a mechanistic and quantitative insight into how MPx/NPx influence the physical structure and hydraulic functioning of soils. It will also build on the existing knowledge by parsing out the roles of environmental moderators and plastic attributes in regulating these interactions. The findings will highlight critical implications for agricultural sustainability under rising plastic pollution and climate variability, and the need to understand these interactions to anticipate risks to soil health, plant productivity, and ecosystem resilience.\u003c/p\u003e"},{"header":"Methodology","content":"\u003cp\u003e\u003cstrong\u003eLiterature search\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePeer-reviewed Publications from the year 2018-2025 (June 2025) were selected for the meta-analysis study using different databases such as Web of Science, Google Scholar, PubMed, Scopus, PubMed, and ResearchGate. A number of keywords were used for the search including \u0026ldquo;plastic particles\u0026rdquo;, \u0026ldquo;microplastic\u0026rdquo;, \u0026ldquo;nanoplastic\u0026rdquo;, \u0026ldquo;soil\u0026rdquo;, \u0026ldquo;soil bulk density\u0026rdquo;, \u0026ldquo;aggregates\u0026rdquo;, \u0026ldquo;porosity\u0026rdquo;, \u0026ldquo;water stable aggregates\u0026rdquo;, \u0026ldquo;soil aggregation\u0026rdquo;, \u0026ldquo;soil texture\u0026rdquo;, \u0026ldquo;soil organic matter\u0026rdquo;, \u0026ldquo;water holding capacity\u0026rdquo;, \u0026ldquo;hydraulic conductivity\u0026rdquo;, \u0026ldquo;water retention capacity\u0026rdquo;, \u0026ldquo;saturated hydraulic conductivity\u0026rdquo;, \u0026ldquo;water repellency\u0026rdquo;, \u0026ldquo;soil water availability\u0026rdquo;, \u0026ldquo;evapotranspiration\u0026rdquo;, and \u0026ldquo;soil organic carbon\u0026rdquo; (Figure 1). We developed and executed a strict search strategy to collect the most relevant,\u0026nbsp;novel, and reliable data sets (Figure S1).\u0026nbsp;As noted above, the initial search returned 1297 research articles, and that group was narrowed to 103 articles (First, reviews, concept papers, opinion articles, and letters lacking primary experimental data were excluded. Second, studies conducted solely in non-soil media or focusing on biodegradation processes, transport mechanisms, or contaminant adsorption were not considered. Due to the limited availability of studies assessing other soil properties beyond hydro-physical and key physic-chemical indicators, papers that did not report data on soil bulk density, porosity, aggregate stability, moisture retention, saturated hydraulic conductivity, or related parameters were excluded from the final dataset) by mandating the following criteria in our search strategy: (i) the study included the application of plastic (MPx or NPx) on agroecosystem (ii) the experiment was conducted under laboratory or field conditions (iii) a control or MPx/NPx-free treatment was included and (iv) the results were supported by appropriate statistical analyses. Only studies that met all four specific criteria were included for meta-analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData extraction\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData were extracted from each peer-reviewed study that met the inclusion criteria, including plastic particle size and concentration (Figure S1), soil physic-hydraulic properties studied (Figure S1), and types of plastics (MPx and NPx), encompassing various polymer types such as polyethylene (PE), polystyrene (PS), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyamide (PA), polylactic acid (PLA), fibers, polyether sulfone (PES), polyethylene terephthalate (PET), Polyvinyl chloride (PVC), polypropylene (PP), and MPx with organic amendments (Figure 1). In the current manuscript, the article search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (Figure S1) (Moher et al. 2009). A total of 103 peer-reviewed research articles were included in the meta-analysis (Figure 2), and data were extracted from figures using WebPlotDigitizer 4.8 software (an open-source online tool).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData endpoints\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the current meta-analysis classified all data endpoints (i.e., the number of observations within the studies) were classified into three main categories and sixteen sub-categories based on their relevance to soil physic-hydraulic properties. These include indicators of hydraulic behavior such as volumetric water content, hydraulic conductivity, and associated biochemical responses (Figure 2). For instance, if a study investigated multiple treatments of MPx or NPx and reported outcomes related to soil hydraulic parameters, particle size, type, and concentration, each treatment-specific endpoint was included as an independent observation. The classification scheme is illustrated in Figure 3. Each category or sub-category was expressed as a percentage, calculated by dividing the number of affected endpoints by the total number of endpoints within the corresponding main or sub-category.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFirst-order meta-analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the current meta-analysis, we used the natural log-transformed response ratio (InRR) method, as described by Hedges et al. (1999) and Gurevitch et al. (2018) to elucidate the impacts of MPx/NPx types, size, and concentration on soil physiological, hydraulic, and biochemical parameters, as illustrated in Figure 3. The following equation was used for calculating the effect size of MPx/NPx.\u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cimg width=\"343\" height=\"46\" src=\"data:image/png;base64,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\" alt=\"image\"\u003e\u003c/p\u003e\n\u003cp\u003eWhere X (treat) denotes the mean value of the treatment group, while X (ctrl) represents the mean of the control group. When studies reported only the standard error (SE), then we calculated the standard deviation (SD) using the formula SD = SE \u0026radic;n, where \u0026ldquo;n\u0026rdquo; was the number of replicates. The estimated size effect was further converted into a percentage using the following equation.\u003c/p\u003e\n\u003cp\u003e\u003cimg width=\"247\" height=\"22\" src=\"data:image/png;base64,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\" alt=\"image\"\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll statistical analysis and data pre-processing were performed by Microsoft Excel 2021 and OpenMEE software (an open source software) (Viechtbauer and Cheung 2010). The pooled effect of the experiments was calculated using a first-order meta-analysis with 95% confidence intervals (CI = 95%) and illustrated as forest plots. Positive values indicate a beneficial effect on plants, while negative values highlight adverse impacts. All forest plots were generated using GraphPad Prism 8 (version 8.0.2) based on data from OpenMEE software.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eComprehensive Effect of plastic on soil\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e presents the grand mean effect sizes (\u0026plusmn;\u0026thinsp;95% confidence intervals) of plastic contamination (primarily microplastics, MPx, and nanoplastics, NPx) on various soil physico-hydrological and soil organic parameters. The collective results (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and Figure S2) show that MPx/NPx pollution causes a mix of positive and negative shifts in soil properties. Bulk density presents a consistently negative effect size, indicating that MPx exposure significantly decreased soil BD by about 5.45%. As plastics have lower density than mineral soil particles, their presence makes the soil matrix lighter and more porous. This BD reduction under MPx is supported by previous studies; for example, mixing microplastics into loamy sand was found to decrease compaction and increase aeration. Soil aggregation was also adversely affected. Indices of aggregate stability, such as the geometric mean diameter (GWD) of aggregates and total macroaggregate content, showed significant reductions (on the order of 0.4\u0026ndash;16%), suggesting that MPx detrimentally impact soil aggregation.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSoil porosity (n\u0026thinsp;=\u0026thinsp;136) presented a positive mean ES (9.42%), meaning that MPx treatment increased the total porosity of soil. In detail, PHB and PET significantly increased total porosity by 47.9\u0026ndash;63.5% (Figure S2A). The increase in porosity is directly linked to the lower bulk density of plastic particles and the ability of MPx particles to generate artificial pore spaces by disrupting soil packing. Correspondingly, water retention metrics responded variably. Field capacity (n\u0026thinsp;=\u0026thinsp;36) shows significantly positive effects (5.65%), suggesting that soils contaminated with plastics tend to retain more water (Figure S2A). Whereas, saturated water content (n\u0026thinsp;=\u0026thinsp;232) and water absorption capacity (n\u0026thinsp;=\u0026thinsp;32) showed a negative response (8.4-15.46%) when exposed to different types of MPx (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). These plastic-induced effects suggest that MPx enhanced the soil\u0026rsquo;s ability to retain water under saturated or near-saturated conditions, possibly because of the increased porosity and a slower drainage process (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Furthermore, the current study revealed that saturated hydraulic conductivity (n\u0026thinsp;=\u0026thinsp;194) and hydraulic conductivity (n\u0026thinsp;=\u0026thinsp;186) showed a strong negative response, meaning that MPx contamination seriously affects the water flow behavior in soils (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and S2C). Interestingly, other water-related parameters such as plant-available water (n\u0026thinsp;=\u0026thinsp;12) and evapotranspiration (n\u0026thinsp;=\u0026thinsp;44) show positive effects (7.25\u0026ndash;17.94%) (Figure S2B). The increase in plant-available water suggests that the incorporation of MPx might change the pore size distribution, which potentially causes an increase in mesopore fractions that contain water plant roots can use (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Soil organic carbon (n\u0026thinsp;=\u0026thinsp;258) also shows a positive ES (6.29%), suggesting that MPx can lead to an increase in measured SOC. This increase may partially be the result of the input of carbon by plastics to the measured pool, as well as indirect MPx effects on the decomposition of organic matter and microbial activities. SOM (n\u0026thinsp;=\u0026thinsp;168) also shows a positive (1.01%) but highly variable response, with a wide CI, indicating no consistent results across the studies (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and S2D).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eImpact of plastic (MPx and NPx) size on soil properties\u003c/h3\u003e\n\u003cp\u003eThe grand mean effect sizes (with 95% CI) of plastic contamination (\u0026lt;\u0026thinsp;200 \u0026micro;m, 200\u0026ndash;1000 \u0026micro;m, \u0026gt;\u0026thinsp;1000 \u0026micro;m, and \u0026lt;\u0026thinsp;100 nm) on a variety of soil hydro-physical, structural, and carbon-related parameters. On the y-axis, the figure lists soil attributes such as bulk density (n\u0026thinsp;=\u0026thinsp;220), soil aggregates (n\u0026thinsp;=\u0026thinsp;40), soil porosity (n\u0026thinsp;=\u0026thinsp;212), soil moisture (n\u0026thinsp;=\u0026thinsp;106), field capacity (n\u0026thinsp;=\u0026thinsp;42), saturated water content (n\u0026thinsp;=\u0026thinsp;232), saturated hydraulic conductivity (n\u0026thinsp;=\u0026thinsp;218), hydraulic conductivity (n\u0026thinsp;=\u0026thinsp;146), water holding capacity (n\u0026thinsp;=\u0026thinsp;128), MWD (n\u0026thinsp;=\u0026thinsp;26), GWD (n\u0026thinsp;=\u0026thinsp;14), water in aggregates (n\u0026thinsp;=\u0026thinsp;162), plant available water (n\u0026thinsp;=\u0026thinsp;48), SOC (n\u0026thinsp;=\u0026thinsp;372) and SOM (n\u0026thinsp;=\u0026thinsp;132) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and S3). The findings of the current study revealed that MPx/NPx sizes exhibited a slight negative effect on soil bulk density, suggesting that the presence of plastic particles tends to reduce bulk density. Aggregate indices (aggregates, MWD, and GWD) also show negative effect sizes, indicating a consistent reduction in soil aggregation or aggregate size in response to plastic contamination. In contrast, MPx/NPx sizes significantly increased the soil porosity, suggesting the tendency of plastic contamination to increase the total soil porosity. Field capacity, water-holding capacity, and plant-available water had slight to significant positive responses to MPx/NPx exposure, suggesting the potential for contaminated soils to retain more water or have higher field capacity. However, water aggregates were significantly reduced under plastic contamination with various sizes (\u0026lt;\u0026thinsp;200 \u0026micro;m, 200\u0026ndash;1000 \u0026micro;m, \u0026gt;\u0026thinsp;1000 \u0026micro;m, and \u0026lt;\u0026thinsp;100 nm). Crucially, plastic contamination strongly impeded soil hydraulic conductivity across particle sizes. Saturated hydraulic conductivity showed a large negative effect size under MPx/NPx presence, and unsaturated hydraulic conductivity was also negatively biased (though not always statistically significant) (Figure S2C).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eEffect of NPx and MPx concentration on soil hydro physical properties\u003c/h2\u003e \u003cp\u003eGrand mean effect sizes (with 95% confidence intervals) for a broad set of soil physical, hydraulic, structural, and carbon-related parameters in response to plastic contamination (spanning from nano- to micrometer scale) in soils. On the vertical axis are listed soil attributes such as bulk density (272), water aggregates (34), porosity (182), soil moisture (40), field capacity (28), saturated water content (234), water absorption capacity (28), saturated hydraulic conductivity (196), hydraulic conductivity (192), water holding capacity (118), MWD (32), GWD (18), water aggregates (152), evapotranspiration (34), plant available water (54), SOC (308), and SOM (163) (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). The numbers in parentheses indicate the number of observations or effect-size records for each parameter. Along the horizontal axis is the effect size scale: zero reflects no overall effect of plastic contamination; negative values denote a decrease in the soil parameter under plastic contamination, while positive values denote an increase. The results outline a multi-faceted pattern of soil responses to plastic contamination. Firstly, bulk density shows a noteworthy negative effect size (the circle is clearly to the left of the zero line), signaling that soils contaminated with plastics tend to have reduced bulk density. In parallel, structural indicators such as MWD and GWD also show negative effect sizes, indicating a decline in aggregate size or stability under plastic contamination. \u0026ldquo;Water Aggregates (152)\u0026rdquo; also displays a modest negative effect size, suggesting that the water held or associated with aggregates is reduced. On the contrary, porosity exhibits a positive effect size (circle to the right of zero), meaning that plastic contamination tends to increase the total porosity of soil. Soil Moisture and Field Capacity likewise show positive shifts, indicating that soils with plastic contamination tend to hold more moisture and have higher field capacity (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). Similarly, saturated water content and water absorption capacity show positive effect sizes, suggesting that the soil\u0026rsquo;s capacity to fill with water and absorb water is increased in the presence of plastics. Though, and importantly, hydraulic flow parameters behave differently. Both saturated hydraulic conductivity and hydraulic conductivity (unsaturated/other conditions) show strong negative effect sizes, with saturated hydraulic conductivity especially shifted far to the left of zero. This suggests that although soils may hold more water (larger water content, higher field capacity), their capacity to transmit or drain water is markedly impaired when plastics are present (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e and S4). Water holding capacity (the ability of soil to retain water accessible to plants) likewise shows a slightly negative effect size. Evapotranspiration and plant-available water show small positive effect sizes, while SOC shows a positive effect size, and SOM again a positive but wide confidence interval (greater uncertainty) (Figure S4). The large CI on SOM also indicates high variability depending on the experimental conditions (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eImpact of plastic exposure duration on soil hydro physical properties\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e explains the summary of how the duration of plastic exposure in soils influences a range of hydro-physical, structural, and carbon-related soil attributes. On the y-axis various soil parameters including bulk density (n\u0026thinsp;=\u0026thinsp;276), aggregates (n\u0026thinsp;=\u0026thinsp;36), porosity (n\u0026thinsp;=\u0026thinsp;212), soil moisture (n\u0026thinsp;=\u0026thinsp;120), field capacity (n\u0026thinsp;=\u0026thinsp;30), saturated water content (n\u0026thinsp;=\u0026thinsp;216), hydraulic conductivity (n\u0026thinsp;=\u0026thinsp;50), water holding capacity (n\u0026thinsp;=\u0026thinsp;108), MWD (n\u0026thinsp;=\u0026thinsp;26), GWD (n\u0026thinsp;=\u0026thinsp;18), water aggregates (n\u0026thinsp;=\u0026thinsp;152), evapotranspiration (n\u0026thinsp;=\u0026thinsp;38), plant-available water (n\u0026thinsp;=\u0026thinsp;54), SOC (n\u0026thinsp;=\u0026thinsp;328) and soil SOM (n\u0026thinsp;=\u0026thinsp;206) are listed, each with the number of observations in parentheses (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). The x-axis displays effect sizes, with zero indicating no overall effect of plastic exposure duration; negative values indicate a decline in a given soil parameter with longer exposure, and positive values indicate an increase. From the plotted means and their confidence intervals, several patterns emerge. First, bulk density shows a slightly negative effect size (the point is just to the left of zero), suggesting that as plastic exposure duration increases, bulk density tends to decline, though the effect is moderate (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eA). Aggregate metrics (e.g., the \u0026ldquo;Aggregates\u0026rdquo; parameter) also trend negatively, indicating that longer plastic exposure may reduce aggregate content or stability in soils. In contrast, porosity shows a small positive effect size, implying that longer exposure to plastics may lead to a modest increase in total pore volume or pore space. Soil moisture shows a slight negative effect, and field capacity likewise appears slightly positive or near zero, but with wide confidence intervals, meaning the evidence is less clear for these parameters under exposure-duration scaling. Saturated water content is very close to zero or slightly positive, but again with limited certainty. Hydraulic conductivity, however, shows a very close to zero (or marginal negative) effect size with a small sample (n\u0026thinsp;=\u0026thinsp;50), suggesting that longer durations of plastic exposure do not consistently amplify or reduce hydraulic conductivity across studies. Water holding capacity shows a small positive effect, meaning that over time, soils with plastics may hold somewhat more water, accessible or stored (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). The structural metrics like MWD and GWD display small negative effect sizes, suggesting that longer exposure leads to slight reductions in aggregate size or geometry. Water in aggregates again shows a marginal negative trend. Evapotranspiration shows a moderate positive effect size, indicating that longer exposure to plastics may increase evapotranspiration rates. Plant available water shows a small positive effect size. Importantly, SOC shows a clear positive effect size; longer plastic exposure is associated with increased SOC levels across the dataset. The SOM parameter likewise shows a positive effect but with very wide confidence intervals, reflecting high variability and lower precision (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eD).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eEffect of exposure medium and presence of plants on soil physico-hydrological indicators\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e presents a subgroup meta-analysis illustrating how different exposure media (incubation, pot, field, and column experiments) influence the effects of plastic contamination on key soil physicochemical and hydrological indicators. Each panel shows overall (grand mean) and medium-specific effect sizes with 95% confidence intervals. Figure\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eA shows the impact of plastics on physical properties, which was determined by a meta-analysis of 20 studies. Plastic exposure significantly decreased bulk density (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and soil aggregate stability (p\u0026thinsp;=\u0026thinsp;0.015), while soil porosity (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) increased in general, indicating that plastics made soils looser and more porous. The effects were larger for pot and incubation experiments. Consistent with our analysis, Chen et al. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2025\u003c/span\u003e) and Wang et al. (\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) reported a lower bulk density in microplastic-amended soils due to the low density of microplastic particles(Chen et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Wang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). The reduction of aggregate stability was also consistent with previous studies and may be related to the physical interference of microplastic particles with soil aggregates. Figure\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eB presents the effects of plastics on the water properties of soil. Soil moisture (p\u0026thinsp;=\u0026thinsp;0.005), field capacity (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and saturated water content (p\u0026thinsp;=\u0026thinsp;0.018) were slightly higher, while water holding capacity (p\u0026thinsp;=\u0026thinsp;0.128) and water aggregates (p\u0026thinsp;=\u0026thinsp;0.676) were not significant under plastic exposure in general, with inconsistent results among different exposure media. Figure S5 includes the effect sizes of different properties (physical, soil water, hydraulic, and organic) with and without plants. The figure uses forest plots to show the effect sizes along with their p-values, which indicate the level of statistical significance of the effect. Each soil property is divided into two sub-categories: with and without plants. The p-values are shown on the right side of the forest plots and help determine if the observed effect is statistically significant or not. The figure shows the effect sizes for different soil properties with and without the presence of plants. In the physical properties category, soil porosity showed a significant effect (I\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;99.39%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating that the presence of plants had a strong influence on porosity. The other properties in this category, such as bulk density, soil aggregates, and GWD, showed no significant effect (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05), but bulk density had a moderate level of variability (I\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;55.72%).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eMicroplastic pollution induces significant changes in soil properties, making soils less compact but more structurally fragile. Our meta-analysis found that bulk density dropped significantly under plastic contamination, consistent with plastics\u0026rsquo; low density and the resulting reduction in soil compaction. Studies have shown similar bulk density declines alongside increased soil aeration when microplastics are mixed into soil (Dong et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Jing et al. \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Likewise, aggregate stability declined in the presence of plastics, as plastic particles interfere with the natural binding agents (organic matter, fungal hyphae, etc.) that hold soil particles together (Tziourrou and Golia \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). A previous study observed that adding plastic fibers reduced macroaggregate formation and increased microaggregate fractions, illustrating this disruption of aggregation (Liang et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). In summary, microplastics make soil structure looser (lower BD, higher porosity) but also less coherent (weaker aggregation). These structural changes also possess strong effects on soil water dynamics as more total pore space, soils with microplastics can retain more water. We observed higher field capacity and increased soil moisture content in contaminated soils, indicating that microplastics generally favor water retention. However, the concurrent loss of aggregate integrity and pore continuity means that drainage is impeded (Mohammed and Zornberg \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2026\u003c/span\u003e). Correspondingly, saturated hydraulic conductivity dropped sharply in our analysis and water infiltrated much more slowly in plastic-contaminated soil. The same additional pores created by microplastics are often poorly connected, so soils hold more water overall but transmit water downward less efficiently (Wang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Similar results found by (Xing et al. \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2025\u003c/span\u003e) where plastics increased soil water retention, they simultaneously decreased infiltration rates. Moreover, (Wang et al. \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) observed that fibrous plastics can clog large soil pores even as they increase small-pore water holding capacity.\u003c/p\u003e \u003cp\u003eMicroplastics also alters soil biogeochemistry, as evidenced by changes in soil organic carbon as we found a moderate increase in SOC in polluted soils. The increment in SOC fractions is likely due to slower organic matter decomposition as microplastics can suppress microbial activity and enzyme access (Song et al. \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Yu et al. \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), leading to a buildup of undecomposed material. Microplastics may also create new microhabitats that physically protect organic matter from decay (e.g. by occluding it within plastic-induced pores) (Lehmann et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Additionally, plastics can also alter measurement of soil organic matter, as (Shi et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) found that microplastic presence raised measured SOC by 21% and microbial biomass up to 17%, but also reduced microbial diversity, indicating a disruption of the soil food web. Thus, higher SOC under contamination likely reflects organic matter accumulating due to impaired breakdown (e.g., via physical protection of organic matter) rather than a true gain in stable humus. Furthermore, the severity of microplastic effects depends on plastic characteristics and exposure duration (Song et al. \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). In our data, smaller microplastic particles (\u0026lt;\u0026thinsp;1 mm) had more pronounced effects than larger fragments. Fine particles have greater surface area and can blend into soil more thoroughly, so such particles increase soil microporosity but significantly decline BD and hydraulic conductivity (Wang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). The duration of plastic exposure emerges as an important factor that can accentuate or slightly modify soil responses to MPx/NPx. Over longer time scales, our results indicate that some changes in soil properties become more pronounced for example, bulk density continued to decrease and porosity to increase with extended exposure, hinting at a cumulative structural loosening of soil over time. This could be due to ongoing microplastic fragmentation or gradual reorganization of soil particles around persistent plastics, effectively reshaping the soil matrix year after year (Liu et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Similarly, the incremental decline in aggregate stability over time suggests that chronic plastic presence might prevent natural processes of aggregate formation or even actively break down existing aggregates through physical abrasion or biophysical interference (e.g. roots and hyphae might be less effective in binding soil that contains plastic fractions) (Fang et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Liang et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2021\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eOur analysis further revealed that plastic effects were generally more pronounced in pot and incubation experiments than in field conditions. In controlled environments, soils are often homogenously mixed with plastics and kept relatively static (no erosion, limited external inputs), so the effects on bulk density, porosity, and other properties manifest clearly. Field studies, however, involve many confounding factors (climate events, bioturbation, heterogeneous distribution of plastics) that can dilute or mask the impact of plastics on measured parameters. For example, we observed that while the direction of change (e.g. reduced bulk density, increased porosity) was consistent, the effect sizes in field studies were typically smaller and sometimes not statistically significant compared to lab studies. This doesn\u0026rsquo;t mean plastics are benign in the field; rather, it reflects higher variability and possibly adaptive responses in real soil ecosystems. Soil in a pot has no new organic inputs except what researchers add, whereas field soil has continuous litter fall, root growth, and other processes that might compensate for some effects (like aggregation by roots counteracting some microplastic-induced dispersion of particles). Nonetheless, even in field settings, we see significant plastic-induced changes, confirming that the phenomena demonstrated in lab studies do translate to real-world conditions. The presence of plants is another crucial factor as living plants interact with soil plastics in multiple ways like, roots can push plastics through the soil profile, exudates might affect plastic surface chemistry, and plants can modulate soil moisture and structure (Wang et al. \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Our results with Figure S5 indicated that plants can amplify certain effects of plastics. Notably, the increase in porosity under plastic contamination was even greater when plants were present. This likely arises because roots create biopores and gaps, and in a plastic-laden soil, those root channels plus the microplastic voids together resulted in higher total pore space (Chaudhary et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Xu et al. \u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e2024b\u003c/span\u003e). In the broader context of ecosystem function, these results suggest that microplastic pollution in soils can interplay with vegetation and land-use in complex ways. Agricultural soils with crops might experience changes in water dynamics due to plastics that could affect irrigation needs or yield (e.g. more water retained near roots but risk of poor drainage). Natural soils with rich biota might buffer some effects (through continuous aggregation processes), but long-term, the persistent presence of plastics still alters the baseline soil condition.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThis meta-analysis indicates that MPx contamination significantly impacted the soil hydro-physical properties. This positive relationship between MPx and most soil hydro-physical parameters was observed. However, some other parameters, such as BD, showed a negative relationship with MPx contamination, and different exposure duration, types of MPs, and concentration also significantly affected the relationships between MPx and soil hydro-physical properties. Although there is a positive correlation between MPx and SOC, although underlying mechanism needs further investigation. Therefore, it is essential to study the long-term effects of MPx on soil structure, water movement, and nutrient cycling, which is a gap in the existing research. Additionally, it is critical to investigate the mechanisms underlying these effects to develop effective soil management practices in MPx-polluted environments.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author would like to thank the Ongoing Research Funding program, (ORF-2026-825), King Saud University, Riyadh, Saudi Arabia for funding this investigation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor\u0026rsquo;s contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSingle Author\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors have read and approved the final version of the manuscript, and everyone has provided their consent for publication of this manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eAwet T, Kohl Y, Meier F, Straskraba S, Gr\u0026uuml;n A-L, Ruf T, Jost C, Drexel R, Tunc E, Emmerling C (2018) Effects of polystyrene nanoparticles on the microbiota and functional diversity of enzymes in soil. 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Environmental Pollution 267: 115544.\u003c/li\u003e\n \u003cli\u003eZhang J, Ren S, Xu W, Liang C, Li J, Zhang H, Li Y, Liu X, Jones DL, Chadwick DR, Zhang F, Wang K (2022a) Effects of plastic residues and microplastics on soil ecosystems: A global meta-analysis. Journal of Hazardous Materials 435: 129065. doi: https://doi.org/10.1016/j.jhazmat.2022.129065.\u003c/li\u003e\n \u003cli\u003eZhang Z, Cui Q, Chen L, Zhu X, Zhao S, Duan C, Zhang X, Song D, Fang L (2022b) A critical review of microplastics in the soil-plant system: Distribution, uptake, phytotoxicity and prevention. Journal of Hazardous Materials 424: 127750.\u003c/li\u003e\n \u003cli\u003eZhao T, Lozano YM, Rillig MCS (2021) Microplastics increase soil pH and decrease microbial activities as a function of microplastic shape, polymer type, and exposure time. Frontiers in Environmental 9: 675803.\u003c/li\u003e\n \u003cli\u003eZhao W, Ge Z-M, Zhu K-H, Lyu Q, Liu S-X, Chen H-Y, Li Z-F (2024) Impacts of plastic pollution on soil\u0026ndash;plant properties and greenhouse gas emissions in wetlands: A meta-analysis. Journal of Hazardous Materials 480: 136167. doi: https://doi.org/10.1016/j.jhazmat.2024.136167.\u003c/li\u003e\n \u003cli\u003eZhou J, Xu H, Xiang Y, Wu J (2024) Effects of microplastics pollution on plant and soil phosphorus: A meta-analysis. Journal of Hazardous Materials 461: 132705. doi: https://doi.org/10.1016/j.jhazmat.2023.132705.\u003c/li\u003e\n\u003c/ol\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":"Microplastic, Nanoplastic, Soil physical, Soil Hydrology, Meta-analysis","lastPublishedDoi":"10.21203/rs.3.rs-8629622/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8629622/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eAims\u003c/h2\u003e \u003cp\u003eMicroplastics (MPx) and nanoplastics (NPx) are widely distributed in agricultural ecosystems, but their effects on soil physico-hydrological properties remain poorly understood.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eTo better constrain the role of MPx/NPx in soil processes and potential impacts, we conducted a meta-analysis on the effects of MPx/NPx on soil bulk density, porosity, water retention, hydraulic conductivity, and soil organic.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThis study indicates that MNPx decreased soil bulk density (2\u0026ndash;6%) and significantly increased porosity (~\u0026thinsp;23%), implying that soil compaction was potentially alleviated. The effects of MNPx on water-related properties (e.g., field capacity, hydraulic conductivity) were inconsistent and depended on the polymer types, concentration, and exposure time. MNP was found to be positively associated with soil organic carbon, suggesting that carbon cycling may be altered. The responses of evapotranspiration and aggregate stability to MPx/NPx were variable, indicating context-dependent effects on soil structure.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eIn conclusion, our study provided quantitative evidence for predicting the mechanistic effect pathways of MPx in altering soil physic-hydrological properties. Nonetheless, both experimental and modeling studies are required to reveal the ecological impacts of MPx under realistic environmental scenarios. This work also pointed out a significant knowledge gap regarding the long-term and field-scale effects of MPx on soil-water interactions and carbon cycling.\u003c/p\u003e","manuscriptTitle":"Effects of Environmentally Relevant Microplastic and Nanoplastic Concentrations on Soil Hydro-Physical Properties: A Global Meta-Analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-17 15:59:42","doi":"10.21203/rs.3.rs-8629622/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":"460546db-5555-473b-a04a-3df9487625c2","owner":[],"postedDate":"February 17th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-17T09:42:54+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-17 15:59:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8629622","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8629622","identity":"rs-8629622","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}