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Sustainable provision of critical ecosystem services in drylands is reliant on their stability under anthropogenic disturbances. Livestock grazing and shrub encroachment are the primary drivers of disturbance that impact their biodiversity and production dynamics. However, the effects of grazing on the stability at multiple scales, particularly following the transition from grass-dominated to shrub-encroached drylands, is still largely unexplored. Here, we conducted comparable sheep-grazing experiments in two types of drylands (grass-dominated vs. shrub-encroached grasslands) on the Mongolia Plateau to explore the effects of grazing and shrub encroachment on biodiversity and stability at multiple scales. We examined how grazing affected the temporal stability of aboveground biomass in herbaceous communities in both grass-dominated and shrub-encroached grasslands, through two potential mechanisms: insurance effects and changes in the population-level stability of individual species. We found that an increase in sheep grazing intensity had significant and negative effects on insurance effects by decreasing both species asynchrony and spatial asynchrony but it had no effects on population stability, consequently leading to reductions in herbaceous community stability of the grasslands. However, grazing-increased insurance effects canceled out grazing-decreased population stability, contributing to no changes in the community stability of shrub-encroached grasslands. Likely, because grazing-induced reductions in the relative abundance of the dominant species were more noticeable in shrub-encroached grasslands than that of in grasslands. Moreover, the grazing-decreased abundance of dominant species was directly correlated to increases in insurance effects in shrub-encroached grasslands but not in grasslands, despite the positive relationships between population stability and the relative abundance of the dominant species in both grass-dominated and shrub-encroached dryla, Sustainable provision of critical ecosystem services in drylands is reliant on their stability under anthropogenic disturbances. Livestock grazing and shrub encroachment are the primary drivers of disturbance that impact their biodiversity and production dynamics. However, the effects of grazing on the stability at multiple scales, particularly following the transition from grass-dominated to shrub-encroached drylands, is still largely unexplored. Here, we conducted comparable sheep-grazing experiments in two types of drylands (grass-dominated vs. shrub-encroached grasslands) on the Mongolia Plateau to explore the effects of grazing and shrub encroachment on biodiversity and stability at multiple scales. We examined how grazing affected the temporal stability of aboveground biomass in herbaceous communities in both grass-dominated and shrub-encroached grasslands, through two potential mechanisms: insurance effects and changes in the population-level stability of individual species. We found that an increase in sheep grazing intensity had significant and negative effects on insurance effects by decreasing both species asynchrony and spatial asynchrony but it had no effects on population stability, consequently leading to reductions in herbaceous community stability of the grasslands. However, grazing-increased insurance effects canceled out grazing-decreased population stability, contributing to no changes in the community stability of shrub-encroached grasslands. Likely, because grazing-induced reductions in the relative abundance of the dominant species were more noticeable in shrub-encroached grasslands than that of in grasslands. Moreover, the grazing-decreased abundance of dominant species was directly correlated to increases in insurance effects in shrub-encroached grasslands but not in grasslands, despite the positive relationships between population stability and the relative abundance of the dominant species in both grass-dominated and shrub-encroached dryla

Sustainable provision of critical ecosystem services in drylands is reliant on their stability under anthropogenic disturbances. Livestock grazing and shrub encroachment are the primary drivers of disturbance that impact their biodiversity and production dynamics. However, the effects of grazing on the stability at multiple scales, particularly following the transition from grass-dominated to shrub-encroached drylands, is still largely unexplored. Here, we conducted comparable sheep-grazing experiments in two types of drylands (grass-dominated vs. shrub-encroached grasslands) on the Mongolia Plateau to explore the effects of grazing and shrub encroachment on biodiversity and stability at multiple scales. We examined how grazing affected the temporal stability of aboveground biomass in herbaceous communities in both grass-dominated and shrub-encroached grasslands, through two potential mechanisms: insurance effects and changes in the population-level stability of individual species. We found that an increase in sheep grazing intensity had significant and negative effects on insurance effects by decreasing both species asynchrony and spatial asynchrony but it had no effects on population stability, consequently leading to reductions in herbaceous community stability of the grasslands. However, grazing-increased insurance effects cancelled out grazing-decreased population stability, contributing to no changes in the community stability of shrub-encroached grasslands. Likely, because grazing-induced reductions in the relative abundance of the dominant species were more noticeable in shrub-encroached grasslands than that of in grasslands. Moreover, the grazing-decreased abundance of dominant species was directly correlated to increases in insurance effects in shrub-encroached grasslands but not in grasslands, despite the positive relationships between population stability and the relative abundance of the dominant species in both grass-dominated and shrub-encroached dryl

Aim: The interactions between plants and soil microbes play crucial roles in modulating the function and stability of terrestrial ecosystems. However, the relationships between plant and soil microbial diversity for different taxa have remained been elusive. Location: Northern China. Major taxa: Plant and soil microbes of grassland ecosystems. Time period: 2018 and 2019. Methods: We conducted a transect survey across grasslands to measure plant diversity, plant traits, and soil microbial diversity. High throughput sequencing was used to assess soil microbial diversity for bacterial 16S ribosomal RNA (16S) and fungal internal transcribed spacer (ITS) regions on an Illumina MiSeq. The random forest algorithm was used to determine the important spatial and environmental variables in predicting plant and microbial diversity, and structural equation modelling was used to examine the direct and indirect effects of climatic and edaphic variables on plant and microbial diversity. Results: Plant diversity was positively correlated with the diversity of soil fungi, particularly for predicted arbuscular mycorrhizal fungi (AMF) and saprotrophic fungi, and they were positively related to soil nutrients and texture. However, the correlation between plant and bacterial diversity varied by phyla and functional guilds, resulting in decoupling between plant and soil bacterial diversity. Community weighted mean leaf C:N ratio indirectly decreased soil fungal diversity through a negative relationship with soil total nitrogen. Soil bacterial and fungal diversity increased with increasing functional richness of specific leaf area and stem density, respectively. Main conclusions: These findings have contributed to unravelling the direct and indirect linkages between plant and soil fungal diversity, highlighting particularly strong linkages between plant diversity and predicted AMF and saprotrophic fungi diversity. However, we failed to detect an overall linkage between plant and soil b