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Plant diversity can significantly affect the grassland productivity and its stability. However, it remains unclear how plant diversity affects the spatial stability of natural grassland productivity, especially in alpine regions that are sensitive to climate change. We analyzed the interaction between plant (species richness and productivity, etc.) and climatic factors (precipitation, temperature, and moisture index, etc.) of alpine natural grassland on the Qinghai-Tibetan Plateau. In addition, we tested the relationship between plant diversity and spatial stability of grassland productivity. Results showed that an increase in plant diversity significantly enhanced community productivity and its standard deviation, while reducing the coefficient of variation in productivity. The influence of plant diversity on productivity and the reciprocal of productivity variability coefficient was not affected by vegetation types. The absolute values of the regression slopes between climate factors and productivity in alpine meadow communities with higher plant diversity were smaller than those in alpine meadow communities with lower plant diversity. In other words, alpine meadow communities with higher plant diversity exhibited a weaker response to climatic factors in terms of productivity, whereas those with lower plant diversity showed a stronger response. Our results indicate that high plant diversity buffers the impact of ambient pressure (e.g., precipitation, temperature) on alpine meadow productivity, and significantly enhanced the spatial stability of grassland productivity. This finding provides a theoretical basis for maintaining the stability of grassland ecosystems and scientifically managing alpine grasslands under the continuous climate change., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Rapid climate warming is altering multiple ecosystem functions of alpine grasslands. However, the responses of the above- and belowground ecosystem multifunctionality (EMF) to climate warming might exhibit difference in semi-arid alpine grasslands. Based on manipulative field experiments at an alpine meadow and an alpine steppe, we explored warming effects on the functioning of alpine grassland ecosystems on the Tibetan Plateau. Warming significantly decreased plant diversity and aboveground biomass, but tended to increase belowground biomass, soil carbon, and soil nutrient contents. Experimental warming generally had neutral effects on the EMF of both alpine grasslands. Nevertheless, warming differentially affects the above- and belowground ecosystem functioning of Tibetan semi-arid alpine grasslands, with the aboveground EMF (AEMF) deceased but the belowground EMF (BEMF) increased under warmer conditions. Our results further showed that the negative effect of experimental warming on AEMF was mainly regulated by the changes of plant and soil biodiversity. However, plant productivity had a pivotal role in propelling the positive effect of warming on BEMF. Our results emphasized the potential impacts of plant and soil biodiversity, productivity, and soil nutrients in maintaining the EMF of alpine grasslands, which could offer novel views for sustainable management of Tibetan semi-arid alpine ecosystems., Competing Interests: Declaration of competing interest The authors declare no competing financial interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

On-going climate warming is threatening the ecological function of grassland ecosystems. However, whether warming has positive effects on community microhabitats and appearance, especially in degraded grasslands, remains elusive. To address this issue, we conducted a 2-year field experiment on the severely degraded alpine meadow and undegraded alpine meadow with no warming and warming treatments. Community coverage and height in degraded meadow significantly increased under warming, while these changes were not significant in undegraded meadow. Two-year warming increased the community height of degraded meadow and undegraded meadow by 56.55% and 10.99%, respectively. Warming also increased community coverage by 41.88% in degraded meadow and decreased community coverage by 3.01% in undegraded meadow. Moreover, the response of topsoil temperature to warming was stronger in degraded meadow (6.89%) than in undegraded meadow (- 0.26%), while the negative response of topsoil moisture to warming was weaker in degraded meadow (- 13.95%) than in undegraded meadow (- 20.00%). The SEMs further demonstrated that warming had positive effects on topsoil temperature and community height, while had negative effects on topsoil moisture both in degraded and undegraded meadows. Our results confirm that warming-induced soil drying is an important pathway affecting the community appearance in alpine meadows. These findings highlight that warming has positive effects on community height and coverage and is particularly effective in improving community coverage appearance in severely degraded alpine meadow with topsoil drying., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The community stability is the main ability to resist and be resilient to climate changes. In a world of climate warming and melting glaciers, alpine gravel encroachment was occurring universally and threatening hillside grassland ecosystem. Gravel encroachment caused by climate warming and glacial melting may alter community structure and community stability in alpine meadow. Yet, the effects of climate warming-induced gravel encroachment on grassland communities are unknown. Here, a 1-year short-term field experiment was conducted to explore the early stage drive process of gravel encroachment on community structure and stability at four different gravel encroachment levels 0%, 30%, 60%, and 90% gravel coverage at an alpine meadow on the Qinghai Tibetan Plateau, by analyzing the changes of dominant species stability and species asynchrony to the simulated gravel encroachment processes. Gravel encroachment rapidly changed the species composition and species ranking of alpine meadow plant community in a short period of time. Specifically, community stability of alpine meadow decreased by 61.78-79.48%, which may be due to the reduced dominant species stability and species asynchrony. Species asynchrony and dominant species stability were reduced by 2.65-17.39% and 46.51-67.97%, respectively. The results of this study demonstrate that gravel encroachment presents a severe negative impact on community structure and stability of alpine meadow in the short term, the longer term and comprehensive study should be conducted to accurate prediction of global warming-induced indirect effects on alpine grassland ecosystems., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)