Reducing plant community variability and improving resilience for sustainable restoration of temperate grassland

Grassland ecosystem is important for the realization of the global sustainable development goals (e.g. Goal 15) since it provides irreplaceable services for human beings, supporting human health and sustainable development. Most studies have focused on improving grassland restoration techniques, but less attention has been paid to grassland ecosystem stability in succession. Plant community stability of temperate grassland in arid and semi-arid regions is analyzed through 38 sampling sites in Inner Mongolia, China. The degradation succession sequence of grassland is established by principal component analysis, and the species diversity and functional diversity along degradation gradient analyzed by multivariate statistical analysis. The results show that (1) functional diversity has higher explanatory power for community stability than species diversity due to the functional dispersion of plant traits; (2) climate factors rather than grazing or soil control plant community diversity and stability at regional scale; (3) the resistance of plant community does not change in degradation succession, but the trade-off effect of stability components in different plant communities differ, such as the order of trade-off effects (e.g. community resilience (ET)＞community resistance (RT)＞structural variability (St)＞functional variability (Fu) in the community dominated by Stipa grandis, RT＞ET＞St＞Fu in Leymus chinensis community, St＞ET＞Fu＞RT in Stipa capillata community, RT＞St＞Fu＞ET in Artemisia frigida community, St＞Fu＞ET＞RT in Cleistogenes squarrosa community, and Fu＞St＞RT＞ET in Artemisia halodendron community); (4) grassland ecosystem with higher diversity shows greater resilience and lower variability than those with single species, which supports the established diversity hypothesis. Furthermore, sustainable grassland restoration should reduce community variability and improve resilience. These findings highlight the response of diversity to stability in temperate grassland and provide scientific support for grassland ecosystem protection and restoration.