Shifting community composition determines the biodiversity–productivity relationship under increasing precipitation and N deposition

作者：Ruiyang Zhang, Michael P. Schellenberg, Dashuan Tian, Fangfang Ma, Tianyou Zhang, Hu Wang, Qian Wu, Y. Bai, Guodong Han, Shuli Niu · 发表于：Journal of Vegetation Science · 年份：2021 · DOI：10.1111/jvs.12998 · 被引用次数：19 · 研究领域：Ecology and Vegetation Dynamics Studies、Plant Water Relations and Carbon Dynamics、Peatlands and Wetlands Ecology

Abstract Questions The relationships between biodiversity and ecosystem functioning (BEF) vary largely across natural ecosystems, with a unimodal, monotonous linear or no relationship. However, it remains unclear how BEF relationships vary under global change. Given future predicted changes in precipitation and nitrogen (N) deposition, it is crucial to determine how precipitation change and N deposition affect grassland biodiversity and productivity, and regulate their relationships. Location A Dry Mixed‐Grass Prairie of western Canada. Methods We established a manipulative field experiment of increased precipitation (water addition with approximately 15% and 30% more monthly precipitation) and N addition (10 g/m 2 ) using a randomized complete block design, including six treatments, each replicated five times (30 plots). We conducted vegetation sampling with a 1 m × 1 m quadrat in each plot from 2016 to 2017, to examine the individual and interactive effects of water and N addition on plant diversity, functional group composition, above‐ and below‐ground productivity, and the diversity–productivity relationships. Results We found a positive linear diversity–above‐ground biomass (AGB) relationship under increased precipitation, which was attributed to the water‐induced increase in the abundance of forbs in the plant community, further promoting the positive effect of plant diversity on AGB. However, N addition caused a negative linear diversity–AGB relationship by increasing ...