Invasive alien plants can indirectly suppress native plants by altering soil biota and nutrient cycling through their litter input. The diversity of litter resulting from co-invasion by multiple species may further modulate these impacts. Fluctuating resources are known to favour many invasive plants; however, it is unclear how nutrient fluctuations alter the effects of litter diversity of invasive plants on native communities. Therefore, we grew a native plant community in a control soil without litter, as well as in soils mixed with litter from one, two, three, and six invasive species under constant or pulsed nutrient supply. Invasive species litter altered soil microbial communities, and increased soil total nitrogen concentration and native community biomass. Under pulsed nutrient supply, native community biomass and soil total phosphorus concentration decreased with increasing litter diversity of the invasive species. However, these effects did not occur under constant nutrient supply. A structural equation model indicated that soil phosphorus and fungal community composition were key mediating factors driving the decrease in native community biomass with increasing litter diversity under pulsed nutrient supply. Our findings underscore that the impact of alien invaders on native communities depends on the diversity of the alien plant litter and nutrient fluctuations.

Root foraging is a common response of plants to heterogeneous soils. Individuals (ramets) of clonal plants are often connected, allowing resource and signal sharing, and thus cooperative responses to environmental heterogeneity. However, it remains unknown how intraspecific and interspecific competition on a ramet influences root foraging of its connected ramet in heterogeneous soils. We grew a younger ramet of the stoloniferous herb Fragaria pentaphylla either in a heterogeneous environment consisting of high- and low-nutrient soil patches or a homogeneous environment containing an even mixture of the two soils, and its connected older ramet in a homogeneous, high-nutrient soil. The older ramet grew alone or with a ramet of the same or a different species (Duchesnea indica, Hydrocotyle sibthorpioides, or Centella asiatica). Regardless of competition, the younger ramet of F. pentaphylla exhibited root foraging in the heterogeneous soil, with a stronger response when its older ramet grew with C. asiatica than when it grew alone. However, growing with other species did not influence root foraging. Root, shoot, and total mass of the younger ramet and the whole clone of F. pentaphylla were higher in the heterogeneous than in the homogeneous soil when the older ramet grew with D. indica or H. sibthorpioides, but such effects disappeared when it grew alone, or with F. pentaphylla or C. asiatica. Our findings suggest that interspecific competition can promote root foraging of clonal plants in heterogeneous soils, but such an effect is context-dependent and not necessarily associated with performance promotion.

Alien plant invasions profoundly influence soil carbon (C) cycling, yet their mechanisms on the priming effect of soil organic carbon (SOC) decomposition are poorly understood. We selected three coastal wetland community types (non-invaded, moderately invaded and highly invaded community by Spartina alterniflora) across five climatically distinct sites in China to clarify the priming effect of soil organic matter decomposition using 13C-glucose tracer method. In the laboratory experiment, the priming effect was positive in all three community types, with the absolute priming values ranging from 15.6 to 108 mg C kg-1 soil. Heavy S. alterniflora invasion enhanced the priming effect by 43.5%- 76.3% compared to non-invaded soils, with this invasion-induced enhancement being more pronounced in tropical and subtropical zones than in temperate zone. S. alterniflora invasion decreased SOC content, nitrogen (N) availability, and microbial biomass and activity, while increasing the microbial C: N ratio. Structural equation modeling (SEM) provided quantitative support for the finding that the reduction in model-derived microbial carbon use efficiency (CUE) emerges as a key mediating factor of the amplified priming effect in S. alterniflora invaded communities. Our findings highlight that plant invasions can accelerate soil C loss via microbial physiological shifts, underscoring the need to incorporate priming mechanisms into C budget assessments of invaded ecosystems.

Effects of parental environments on offspring phenotypes are ecologically and evolutionarily important for plants. As clonal offspring develop close to their parents and their environments are predictable, plant clonality is hypothesized to influence adaptive parental effects. We conducted a meta-analysis of parental effects on offspring performance of clonal and non-clonal plant species. Offspring performance was extracted from experiments that evaluated offspring in both benign and stressful environments, with parents originating from the same benign or stressful environments. Parental effects generally enhanced offspring performance under matching (predictable) parent-offspring environments, but their direction and intensity varied depending on the environmental context and clonality. Parental effects positively affected offspring growth, reproductive and morphological traits of clonal plant species in predictable benign environments, but parental effects were significantly stronger on growth, morphological and physiological traits of non-clonal plant species in predictable stressful environments. For clonal plant species only, parental effects on reproductive traits were more positive in clonally derived than in sexually derived offspring in predictable benign environments, but more positive in sexually derived than in clonally derived offspring in predictable stressful environments. Synthesis. Plant clonality enhances parental effects on offspring performance in predictable benign environments, but does not increase the chance of adaptive parental effects in predictable stressful environments. The findings highlight the importance of considering reproductive modes and environmental contexts in parental effects on offspring phenotypes.

Soil nutrient heterogeneity can influence the performance of both native and alien plants. However, such effects may be modified by native generalist herbivores and this modification may differ between native and alien plants due to differences in co-evolutionary histories with the herbivores. In a greenhouse experiment, we grew two native and two alien plants either alone or in native-alien pairs in homogeneous or heterogeneous soils, with or without the native generalist herbivore Spodoptera litura. Total biomass of the native plant Alternanthera sessilis and the alien plant Celosia argentea was lower in the heterogeneous than in the homogeneous soils, indicating an overall negative effect of soil nutrient heterogeneity. Although the heterogeneity × herbivory interaction was not significant, post-hoc comparisons revealed species-specific patterns. For A. sessilis, the lowest total biomass occurred in heterogeneous soils under herbivory, whereas the other treatment combinations did not differ significantly. In contrast, for C. argentea, total biomass differences between homogeneous and heterogeneous soils were evident only in the absence of herbivores. Belowground biomass analyses suggest that the contrasting responses were likely to result from species-specific, herbivore-induced trade-offs between the benefits and costs of root foraging precision in heterogeneous soils. These effects, however, were not observed for the native plant Achyranthes bidentata or the alien plant Amaranthus retroflexus. Competition with alien plants reduced aboveground biomass of both native plants, whereas the alien plants were unaffected by competition with natives. Competition did not alter the effects of soil heterogeneity or herbivory. These results indicate that soil nutrient heterogeneity and native generalist herbivores may jointly shape the performance of native and alien plants in a species-specific manner, regardless of competition between them.

Maintaining ecological stability is essential for sustaining ecosystem functions and the benefits they provide to society. Ecological theory predicts that plant diversity destabilizes local populations, yet empirical studies report variable effects. We hypothesize that this discrepancy arises at least in part from differences captured by different diversity (average vs cumulative richness, i.e. the mean annual richness vs the cumulative richness across years) and stability metrics (abundance-unweighted vs weighted mean population stability). To test this, we analyzed data from > 8000 permanent vegetation plots across biomes on five continents. We found a negative (i.e. destabilizing) diversity-stability relationship when using abundance-weighted rather than unweighted measures of population stability, which are more influenced by dominant species. Similarly, cumulative richness - capturing total species occurrence over time and long-term turnover - reveals a stronger destabilizing effect compared to average annual richness. Our findings reveal that, when specific metrics of diversity and stability are considered, more species and potentially the associated increase in interspecific competition tend to destabilize populations across natural ecosystems world-wide - particularly those of dominant species.

Priming effects play an important role in controlling soil organic matter (SOM) decomposition and global carbon (C) cycle. Although numerous studies have investigated the effect of inorganic nitrogen (N) addition on priming effects, large uncertainties remain regarding whether different N forms (e.g., organic versus inorganic) have divergent impacts. To examine how long-term N addition with different N forms and application rates alters soil properties and thereby influences the priming effects, 13C-labelled glucose was added to soils from a semi-arid grassland that had received inorganic- (ammonium nitrate and ammonium sulfate) or urea-N of varying rates (0, 5, and 50 g N m-2 yr-1) for five years. Our results showed that effect of N application history on priming depends on application rates. Only the high-rate (50 g N m-2 yr-1) inorganic N addition significantly decreased the cumulative priming effect, likely due to elevated N availability and soil acidification. In contrast, high-rate urea amendment exerted no significant effect on the cumulative amount of primed C. Across all treatments, the cumulative priming effect was negatively correlated with soil total N concentration, but positively correlated with pH and soil C:N. Importantly, net N mineralization rates were positively correlated with the magnitude of priming, reinforcing the role of N availability in regulating the priming effect. We conclude that different forms and rates of long-term N addition result in distinct soil properties (e.g., soil C:N, N availability, and soil acidity) that ultimately regulate the susceptibility of SOM to priming. Our findings underscore that predicting soil C cycle in scenarios of increased N deposition requires accounting for form-specific alterations in soil properties.

Abstract. Long-term, high-resolution canopy cover data are essential for understanding grassland ecosystem dynamics and informing sustainable management. However, existing products are largely limited to coarse spatial resolutions, constraining their utility for high-precision, large-scale analyses. In this study, we collected over 16,000 drone image tiles (30 m × 30 m) from 2,144 sites across China and developed a machine learning model to produce a spatially seamless, 30 m annual dataset of national grassland canopy cover from 1990 to 2023 by integrating drone and Landsat-series imagery. The model achieves high predictive accuracy (R2 = 0.73, RMSE = 18.4 %) and robust temporal transferability (R2 = 0.68, RMSE = 20.6 %). Comparisons with existing large-scale products demonstrated significantly improved accuracy and reduced residual artifacts, underscoring the robustness of our approach across diverse grassland types and time periods. Spatiotemporal analysis indicated a multi-decadal mean canopy cover of 43.80 ± 18.69 % across China’s grasslands. Over the 34-year period, 41.76 % of grasslands exhibited significant increases, 57.16 % showed nonsignificant change, and 1.08 % experienced significant declines. Climatic factors—including drought, precipitation, and temperature—emerged as the dominant drivers of canopy cover dynamics at the national scale, although their effects exhibited pronounced spatial heterogeneity. In contrast, anthropogenic pressures played a secondary role overall but could override climatic influences at local scales. Collectively, these findings, together with the long-term, high-resolution canopy cover dataset developed in this study, provide an essential basis for advancing the understanding of grassland ecosystem dynamics and for supporting evidence-based conservation and sustainable management strategies, particularly under intensifying climate change and increasing frequency of extreme events. The national grassland canopy cover dataset generated in this study is archived on Zenodo and can be freely downloaded from https://doi.org/10.5281/zenodo.20301123 (Jiang et al., 2026).

Abstract Soil microbes and their mediation of biogeochemical processes play critical roles in soil organic carbon (SOC) formation and persistence and can be significantly affected by water-table changes in peatlands. However, it is still unclear how water-table changes alter microbial attributes associated with microbial-derived carbon (C) pools, particularly in peatlands where soils have very high organic matter and low redox potential. We manipulated water-table declines in an alpine peatland on the Qinghai-Tibetan Plateau, measured soil microbial composition and microbial attributes (e.g. extracellular enzyme activities, and hydrolytic and ligninolytic gene abundances), and quantified living microbial biomass (via microbial biomass carbon) and microbial residues (via amino sugar biomarkers). Declining water tables reduced both living microbial biomass and microbial residues, thereby decreasing microbial-derived C pools, but increased hydrolytic and/or ligninolytic gene abundances and enzyme activities, suggesting enhanced microbial C-acquisition attributes. Water-table decline and the associated reduction in soil water content induced taxonomic shifts in the microbial community with significant phylogenetic signals, indicating that hydrological change acts as an environmental filter favoring aerobic C-decomposing taxa such as Sphingorhabdus and Gemmatimonas. Our findings highlight that these microbial responses, together with shifts in key microbial taxa, influence the effects of water-table changes on microbial-derived C pools in peatlands, and point out the importance of water level management in maintaining peatlands.

Biological invasions and environmental gradients are major drivers of biodiversity change in wetland ecosystems, but their associations on native plant diversity in Central Asian riverine wetlands remain poorly understood. We surveyed 158 wetland plant communities across 54 transects in the Ertix River Basin to examine how environmental gradients (elevation, mean annual temperature [MAT], and mean annual precipitation [MAP]) and non-native plant establishment jointly related to native plant importance values and alpha diversity indices. Non-native plants were classified according to invasion stage—non-naturalized, naturalized, and invasive—to elucidate how the associations between alien plants and native communities shift dynamically along the invasion continuum. Elevation emerged as the dominant predictor, explaining 82% (individual R2 = 0.15) of the variance in native species richness and 63.37% (individual R2 = 0.1) of the variance in the Shannon–Wiener diversity index, while MAT and MAP were not retained as significant predictors in the optimal models. Native plant importance values, richness, and diversity all increased with elevation. Unexpectedly, naturalized plant richness and abundance were positively associated with native diversity metrics, contrasting with the negative associations of all non-native categories (non-naturalized, naturalized, and invasive) on native importance values, partly reflecting the compositional nature of this metric. Our results reveal positive co-occurrence patterns between early-stage naturalized species and native species, but native dominance may eventually decline as invasion intensity increases. These findings highlight the importance of considering invasion stage when predicting wetland biodiversity responses to biological invasions under environmental heterogeneity.

Genetic diversity within plant populations is a key determinant of ecosystem functioning, especially, in shaping plant productivity. However, existing research examining how genetic diversity influences productivity has primarily focused on genotypic richness (number of genotypes), leaving the role of genotypic evenness (relative abundance of genotypes) understudied. Moreover, while microplastics has become a widespread contaminant, it is unknown whether microplastics could influence the impact of genetic diversity on plant growth performance. To address these gaps, we conducted an experiment using the clonal plant Hydrocotyle verticillata, manipulating both genotypic richness (1, 3, 6) and genotypic evenness (low, medium, high), crossing treatments with three types of soil microplastics (polylactic acid (PLA), poly-3-hydroxybutyrate (PHB) and polybutylene succinate (PBS)) and a control group without microplastics. All three microplastics significantly decreased biomass of H. verticillata. Genotypic richness had no effects on biomass, however, its effect on ramet numbers was altered by microplastics. The effect of genotypic evenness on both biomass and ramets were regulated by microplastics. With PBS, H. verticillata with high genotypic evenness produced significantly lower biomass and ramet numbers than those with low or medium evenness. However, this pattern was not observed under the PHB or PLA treatments. The study concludes that microplastics can modulate the effects of genotypic richness and evenness on the population performance of H. verticillata, but the effects vary depending on the type of microplastics. Our findings highlight the role of microplastics in regulating biodiversity-productivity relationships.

Nitrogen deposition is a key global change driver that can alter soil processes and ecosystem functioning in forest ecosystems. Biochar is widely used as a soil amendment to improve soil properties and ecosystem functioning, yet how biochar regulates soil multifunctionality (SMF) across different nitrogen deposition levels remains poorly understood, particularly in plantation forests. Here, we conducted a field experiment in mature Larix kaempferi plantations to examine how biochar addition influences SMF across simulated nitrogen deposition levels and to explore the microbial mechanisms underlying these responses. The effects of biochar on SMF were strongly dependent on nitrogen addition levels. Biochar increased SMF under both ambient and high nitrogen additions, but reduced SMF under low nitrogen addition when applied at high biochar rates, indicating context-dependent responses of SMF to biochar under varying nitrogen deposition conditions. SMF was more strongly associated with fungal richness and community composition, whereas bacterial community properties and microbial network attributes showed only weak associations with SMF. Structural equation modeling revealed that fungal community composition directly influenced SMF and acted as a major pathway through which biochar application affected SMF. Although biochar significantly altered microbial network structure, these changes were not strongly associated with variation in SMF. Overall, our results indicate that biochar regulates SMF under different nitrogen deposition levels primarily through shifts in fungal community rather than through changes in bacterial community and microbial interaction networks. These findings highlight the importance of accounting for nitrogen deposition context when applying biochar in subtropical plantation forests.

Root-mediated conspecific recognition and avoidance could alleviate intraspecific competition and promote interspecific competitive abilities. This could result in communities dominated by few species. However, it remains unclear whether invasive plants, which frequently become dominant, possess higher capabilities of root recognition and segregation than natives. We compared root-recognition and segregation capabilities between five congeneric pairs of invasive and native plants using a split-root assay and an intraspecific root-distribution experiment. We also assessed the roles of soil microbial legacies in root-segregation capabilities. The split-root assay showed that invasive plants exhibited stronger root-recognition capacities than natives by reducing root allocation toward conspecifics. The intraspecific root-distribution experiment showed that both invasives and natives exhibited root segregation when grown on unconditioned soils. However, when grown on soils conditioned by either invasive or native plants, root segregation of natives disappeared, whereas invasives remained unaffected. Changes in root segregation of natives were associated with changes in the composition of soil fungal and bacterial communities. Invasive plants possess mechanisms of avoiding intensive intraspecific competition irrespective of soil microbial legacies, whereas for native plants, these mechanisms can be disrupted by soil microbial legacies. This could contribute to the competitive superiority of invasive plants.

Genetically induced phenotypic diversity can drive overyielding in plant communities via resource partitioning, pathogen dilution, and abiotic stress alleviation. Theoretically, environmentally induced phenotypic diversity within genetically uniform populations could also generate overyielding through these mechanisms. Testing this possibility will expand the generality of biodiversity-ecosystem functioning relationships.

Soil nutrient heterogeneity is common in nature, but few studies have tested the effects of soil nutrient heterogeneity on plant productivity in natural communities. Such effects are of particular interest in habitats where heterogeneity may be increasing due to global warming, as in high-elevation grassland on the Qinghai-Tibetan Plateau. In a three-year study, we added N, P, and K to 2 m × 2 m plots in grassland to establish five homogeneous and six heterogeneous treatments that varied in patch size, patch contrast (difference in nutrient levels between patches), and number of patch types (with different nutrient levels). We measured aboveground biomass of grasses, other graminoids, legumes, and forbs. Biomass of grasses was higher (over 300g/m2) and that of legumes was lower (about 25g/m2) at higher nutrient availability in homogeneous treatments. Within heterogeneous plots, grasses similarly had about 25% higher biomass and legumes had about 60% lower biomass in patches with higher nutrients, mainly at the larger patch size and sometimes more so when patch contrast was greater. Accounting for 47-61% of the total aboveground biomass, grasses showed a roughly similar pattern to that of the whole community. An increase in soil nutrient heterogeneity is unlikely to affect plant aboveground biomass in this grassland, although it can increase biomass of grasses and decrease that of legumes. Soil nutrient heterogeneity might partly mitigate these effects if large patches without elevated nutrients persist.

Information on the determinants of taxonomic and phylogenetic diversity of invasive plant species is crucial for managing invasive plants. With globalization, most countries have experienced substantial economic losses and environmental damage due to biological invasions. We analysed the determinants of variation in the diversity and phylogenetic structure of invasive plants among countries worldwide. To do so, we used a comprehensive checklist of invasive plants in 152 countries worldwide to calculate taxonomic and phylogenetic diversity (i.e. Faith’s PD metric) and phylogenetic structure, using mean phylogenetic distance (MPD) and mean nearest taxon distance (MNTD). We then combined these data in minimum adequate models with data on geographic, climatic, socio‐economic and international trade variables. We also conducted randomization tests to determine whether the phylogenetic diversity of invasive plants in these countries was clustered or overdispersed. Taxonomic and phylogenetic diversity of invasive plants exhibited spatial congruence. Taxonomic and phylogenetic diversity were positively correlated with insularity, mean annual precipitation (MAP) and HS‐12 (seeds, grains and medicinal plants) import values per capita, but negatively associated with mean annual temperature (MAT) and HS‐07 (vegetables) import evenness. In addition, taxonomic diversity also increased with airport density, HS‐12 import evenness and lower HS‐08 (fruit and nuts) imports. MPD increased with greater land area and airport density and fewer HS‐12 exporting source countries. MNTD increased with MAT but declined with greater land area and insularity. Phylogenetic clustering occurred in 28.9%–49.3% of countries, whereas phylogenetic overdispersion was rare, observed only in 0.6%–5.3% of countries. Synthesis . Our study reveals that variation in taxonomic and phylogenetic diversity of invasive plant species among countries is shaped by geographic, socio‐economic, climatic and international trade factors. Nearly one‐third of the countries showed phylogenetic clustering of invasive plant species, indicating a relatively consistent global pattern. These findings underscore the importance of integrating both taxonomic and phylogenetic perspectives in invasion ecology, emphasizing the need for regionally tailored management strategies that effectively account for regional geographic, climatic, socio‐economic and trade‐related factors to mitigate future plant invasions.

Carbon (C) allocation among different plant tissues is crucial for maintaining C balance in forest ecosystems, especially under changing climate conditions. The partitioning of newly assimilated C among plant tissues, interconnected ramets and soil in forests dominated by giant clonal plants, such as moso bamboo ( Phyllostachys edulis ), and the influence of drought on this partitioning remain poorly understood. In August 2019, we performed in situ labelling of the entire crown of R0 (ramets that emerged in 2019) of moso bamboo with 13 CO 2 in plots subjected to a 5‐year drought or left untreated (ambient control) in subtropical China. We then traced the 13 C signatures in the leaves, twigs and fine roots of R0, R1 (ramets that emerged in 2018 and are connected with R0) and R2 (ramets that emerged in 2017 and are connected with R1), as well as in soil organic C (SOC) and soil respiration over the course of 1‐year post‐labelling. Drought reduced leaf 13 C assimilation and its allocation to sink tissues but did not alter the velocity of C transport from source to sink compared to controls. The peak 13 C signal was observed on day 15 for SOC and on day 5 for respired CO 2 in both drought and ambient control forests. Labelled 13 C was detected in R1 ramets on day 3 and in R2 on day 7 post‐labelling. This study reveals that new assimilates produced by the ‘younger’ R0 ramets are preferentially retained within their own tissues to meet their own demands rather than being allocated to interconnected neighbouring R1 and R2 ramets. Synthesis . In forests dominated by large clonal plants, such as giant moso bamboo, drought can alter the allocation of newly assimilated C within the tissues of source ramets but may not affect its allocation among interconnected ramets or within plant–soil systems. Our findings highlight the complexity of newly assimilated C partitioning in these forests and suggest that clonal integration may mitigate drought‐induced dieback in older ramets through resource sharing under climate change.

Although numerous studies have independently tested the roles of physiological integration and parental effects on the performance of clonal plant species, few have assessed them simultaneously. Moreover, the capacity for physiological integration differs greatly within species of clonal plants. We conducted a greenhouse experiment with eight genotypes of the clonal herb Hydrocotyle verticillata. In the first phase, we either severed or maintained the connections between the original proximal nodes (the basal portion) and the new distal nodes (the apical portion) of each genotype. In the second phase, the ramets in the apical portion produced in the first phase were selected and cultivated, and their connections were subjected to the same severance treatments. In the first phase, the negative effects of severance on the apical portion balanced the positive effects of severance on the basal portion, resulting in no net effect of severance on total mass, leaf mass, stem mass, and ramet number for the whole clone. In the second phase, the effects of parental severance on stem mass of the apical portion of H. verticillata varied among the eight genotypes. Additionally, the positive effect of physiological integration on offspring generations was greater in the apical portion and the whole clone of one genotype when the parental connections were intact than when they were severed, whereas it was greater in the apical portion of another genotype when the parental connections were severed than when they were intact. Our results suggest that clonal parental effects can influence the capacity for physiological integration of offspring generations and that these effects may differ among genotypes within a species.