Seasonal community stability increased with water addition and shrub removal but reduced with nitrogen addition in semi-arid grassland

1. Stability is a useful indicator of the functioning and sustainability of an ecosystem, and many studies have explored the effects of anthropogenic disturbance on the inter-annual stability of plant communities. However, the effects of multiple anthropogenic stressors on seasonal community stability have not been clearly elucidated, especially for vulnerable semi-arid grasslands. 2. During the growing season in the 5th year of the experiment, we determined how nitrogen (N) addition, water addition, and shrub removal altered seasonal community stability in a semi-arid grassland dominated by the shrub Caragana microphylla on the Mongolian Plateau. 3. We found that shrub removal, N addition, and water addition had different effects on the stability of the community and plant functional groups (PFGs). Shrub removal increased seasonal community stability mostly via increases in the stability of perennial forbs and C4 plants, and shrub removal did not alter the effects of N addition or wate..., ,1. 稳定性是衡量生态系统功能与可持续性的重要指标，既往诸多研究已探讨了人为干扰对植物群落在年际尺度上稳定性的影响。然而，多重人为胁迫因子对群落季节稳定性的影响尚未得到清晰阐明，针对脆弱的半干旱草原而言尤为如此。 2. 本研究于实验开展的第5个生长季，在蒙古高原以小叶锦鸡儿（Caragana microphylla）为优势灌木的半干旱草原样地中，探究了氮（N）添加、补水处理及灌木移除对群落季节稳定性的调控效应。 3. 研究结果显示，灌木移除、氮添加与补水处理对群落及植物功能群（PFGs）的稳定性存在差异化影响。其中，灌木移除主要通过提升多年生草本植物与C4植物的稳定性，进而增强群落季节稳定性，且灌木移除并未改变氮添加及补水……