Institute of Ecology, College of Urban and Environmental Science, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China.
Ministry of Education Key Laboratory of Ecology and Resources Use of the Mongolian Plateau, School of Ecology and Environment, Inner Mongolia University, Hohhot, China.
Ecol Lett. 2021 Oct;24(10):2054-2064. doi: 10.1111/ele.13826. Epub 2021 Jul 28.
Livestock grazing is a major driver shaping grassland biodiversity, functioning and stability. Whether grazing impacts on grassland ecosystems are scale-dependent remains unclear. Here, we conducted a sheep-grazing experiment in a temperate grassland to test grazing effects on the temporal stability of productivity across scales. We found that grazing increased species stability but substantially decreased local community stability due to reduced asynchronous dynamics among species within communities. The negative effect of grazing on local community stability propagated to reduce stability at larger spatial scales. By decreasing biodiversity both within and across communities, grazing reduced biological insurance effects and hence the upscaling of stability from species to communities and further to larger spatial scales. Our study provides the first evidence for the scale dependence of grazing effects on grassland stability through biodiversity. We suggest that ecosystem management should strive to maintain biodiversity across scales to achieve sustainability of grassland ecosystem functions and services.
放牧是塑造草原生物多样性、功能和稳定性的主要驱动因素。放牧对草原生态系统的影响是否依赖于规模尚不清楚。在这里，我们在温带草原进行了一项绵羊放牧实验，以测试放牧对生产力在不同尺度上的时间稳定性的影响。我们发现，放牧增加了物种的稳定性，但由于群落内物种之间的异步动态减少，大大降低了群落的局部稳定性。放牧对局部群落稳定性的负面影响会进一步降低较大空间尺度上的稳定性。放牧通过减少群落内和群落间的生物多样性，降低了生物保险效应，从而降低了从物种到群落再到更大空间尺度稳定性的扩大。本研究通过生物多样性首次提供了放牧对草原稳定性的影响具有尺度依赖性的证据。我们认为，生态系统管理应该努力维持生物多样性的各个尺度，以实现草原生态系统功能和服务的可持续性。
