Change in functional trait diversity mediates the effects of nutrient addition on grassland stability

作者：Qingqing Chen, Shaopeng Wang, Eric W. Seabloom, Forest Isbell, Elizabeth T. Borer, Jonathan D. Bakker, Siddharth Bharath, Christiane Roscher, Pablo L. Peri, Sally A. Power, Ian Donohue, Carly Stevens, Anne Ebeling, Carla Nogueira, Maria C. Caldeira, Andrew S. MacDougall, Joslin L. Moore, Sumanta Bagchi, Anke Jentsch, Michelle Tedder, Kevin Kirkman, Juan Alberti, Yann Hautier · 发表于：Journal of Ecology · 年份：2024 · DOI：10.1111/1365-2745.14404 · 被引用次数：12 · 研究领域：Ecology and Vegetation Dynamics Studies、Ruminant Nutrition and Digestive Physiology、Rangeland and Wildlife Management

Abstract Nutrient enrichment impacts grassland plant diversity such as species richness, functional trait composition and diversity, but whether and how these changes affect ecosystem stability in the face of increasing climate extremes remains largely unknown. We quantified the direct and diversity‐mediated effects of nutrient addition (by nitrogen, phosphorus, and potassium) on the stability of above‐ground biomass production in 10 long‐term grassland experimental sites. We measured five facets of stability as the temporal invariability, resistance during and recovery after extreme dry and wet growing seasons. Leaf traits (leaf carbon, nitrogen, phosphorus, potassium, and specific leaf area) were measured under ambient and nutrient addition conditions in the field and were used to construct the leaf economic spectrum (LES). We calculated functional trait composition and diversity of LES and of single leaf traits. We quantified the contribution of intraspecific trait shifts and species replacement to change in functional trait composition as responses to nutrient addition and its implications for ecosystem stability. Nutrient addition decreased functional trait diversity and drove grassland communities to the faster end of the LES primarily through intraspecific trait shifts, suggesting that intraspecific trait shifts should be included for accurately predicting ecosystem stability. Moreover, the change in functional trait diversity of the LES in turn influenced different fa...