Community-level trait responses and intra-specific trait variability play important roles in driving community productivity in an alpine meadow on the Tibetan Plateau

Abstract

Aims Human activities have dramatically increased nutrient inputs to ecosystems, impacting plant community diversity, composition and functioning. Extensive research has shown that a decrease in species diversity and an increase in productivity are a common phenomenon following fertilization in grasslands ecosystem. The magnitude of the response of species diversity and above-ground net primary productivity (ANPP) to fertilization mainly depends on species traits (mean trait values) and traits variability (plasticity). Our aim of this study was to examine (i) changes of species diversity (species richness and Shannon-Wiener index) and ANPP following fertilization; (ii) which species traits or communityweighted mean (CWM) traits can determine ANPP, as expected from the ‘biomass ratio hypothesis'; and (iii) the relative role of intra-specific and inter-specific trait variability in this process following fertilization. Methods We measured ANPP and four key plant functional traits