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Questions: Although the relationships between biodiversity and individual ecosystem functions under resource enrichment have been extensively studied, there is limited understanding of how resource‐induced changes affect ecosystem multifunctionality and its temporal stability, along with the underlying biological mechanisms. Location: Inner Mongolia, China. Methods: We investigated the impact of biodiversity mechanisms on ecosystem multifunctionality and its temporal stability through a 3‐year field experiment. This experiment involved augmenting growing season precipitation and nitrogen deposition, conducted in a typical steppe ecosystem of Inner Mongolia alongside regular mowing. Results: Our findings revealed that the addition of water (W) and nitrogen (N) had varying effects on ecosystem multifunctionality and its temporal stability. The combination of N and W additions enhanced ecosystem multifunctionality, whereas both W and N + W additions promoted the temporal stability of ecosystem multifunctionality. Structural equation modeling demonstrated that the community‐weighted mean height, in response to nitrogen addition, played a key role in enhancing ecosystem multifunctionality. By contrast, increased species asynchrony because of water addition and greater functional diversity in terms of leaf area contributed to heightened temporal stability of ecosystem multifunctionality. Furthermore, the positive effects of community‐weighted mean height on ecosystem multifunctionality exhibited a gradual increase with rising threshold levels. Conclusions: Our study provides the first evidence of the independent effects of selection, exemplified by community‐weighted mean and complementarity, represented by factors such as species richness, functional diversity and species asynchrony on both ecosystem multifunctionality and its temporal stability. This underscores how global change factors can directly influence ecosystem multifunctionality and its temporal stability while also indirectly modulating biodiversity effects in the short term. Overall, our findings underscore the vital role of biodiversity conservation in enhancing grassland management and the delivery of ecosystem services in the context of global change, particularly in regions subject to extensive mowing. [ABSTRACT FROM AUTHOR]

Although livestock grazing can strongly affect pools and cycles of phosphorus (P) in grassland ecosystems, few studies have examined how grassland management regimes influence the components of the soil P pool. Here, we use a long-term experiment in the Inner Mongolia grassland to examine how grassland management and biotic and abiotic factors affect soil P fractions. The grassland management regimes we studied included a traditional grazing system (continuous grazing, TS), a mixed grazing system (grazing and mowing rotation, MS), and a haymaking system (continuous mowing, HS). Our results showed that traditional grazing accelerated the return of P to ecosystems lost by herbivores and decoupled labile P (i.e., Ca2-P) from soil organic carbon in the topsoil (0–10 cm). Labile P was significantly reduced in the topsoil in HS (− 10%) and MS (− 24%). Mowing promoted the downward movement of soil P and the transformation of O-P to Ca2-P in the topsoil by removing large amounts of biomass and litter. Both grazing and mowing increased Fe-P and Ca10-P concentrations. The amount of labile P in the topsoil was mainly explained by plant properties, whereas the amounts of moderately labile P (Ca8-P, Al-P and Fe-P) and stable P (O-P and Ca10-P) were mainly explained by soil properties. Moreover, shifts in plant community composition resulted in substantial impacts on the soil stable P fractions. Our study demonstrates that long-term continuous grazing is detrimental to the accumulation of available nutrients in soils. Understanding how grazing and mowing affect conversion between P pools could improve adaptive grassland management in the face of global change. [ABSTRACT FROM AUTHOR]

Predicting the comprehensive driver of ecosystem multifunctionality is crucial for effective grassland management. However, the underlying biotic and abiotic mechanisms of ecosystem multifunctionality under global change and land use remain poorly understood. In this study, a 3-year field experiment was conducted in a semi-arid steppe in Inner Mongolia to investigate the relative importance of different biotic and abiotic factors in regulating aboveground ecosystem multifunctionality (AEM) and belowground ecosystem multifunctionality (BEM) in response to resource input after long-term grazing. The experiment involved three grazing intensities (1.5 low, 4.5 moderate, and 9.0 high sheep/ha) with a 7-year difference in grazing history. Precipitation (W) and nitrogen deposition (N) were manipulatively increased during the growing season. The study focused on exploring the effects of various biotic factors (e.g. species richness, functional diversity, plant functional groups) and abiotic factors (e.g. soil environment variables) on AEM and BEM. The results revealed asymmetric responses of AEM and BEM to resource input. Resource input enhanced AEM, but not BEM. However, increasing grazing intensity substantially reduced BEM, though we noted that AEM and BEM decreased the most under moderate grazing. Interestingly, the study found consistent responses of single ecosystem functions and ecosystem multifunctionality to resource input across the three grazing blocks. Structural equation modeling (SEM) analysis indicated that species richness primarily enhanced AEM, while soil environment played a major role in promoting BEM across different grazing history intensities and the whole grazed system. Multiple biotic and abiotic factors with varying relative importance in different grazing history scenarios controlled AEM and BEM. Species richness exhibited a strong influence on AEM and BEM, but within a narrow effect threshold range, whereas soil environment had a lesser effect size but a wider threshold range. This study provides the first evidence that grazing history and resource enrichment jointly regulate AEM and BEM. The findings highlight the importance of considering biodiversity conservation, soil health, and land use history in management practices aimed at maintaining ecosystem multifunctionality under climate change and human activities scenarios. • AEM and BEM decreased the most under grazing history with moderate intensity. • Resource input enhances AEM and maintains BEM after long-term grazing. • Species richness and soil factors primary controls AEM and BEM, respectively. [ABSTRACT FROM AUTHOR]