Plant Elemental Homeostasis Enhances Species Performance and Community Functioning in Wetlands: Looking Beyond Nitrogen and Phosphorus

Abstract

Understanding how species optimise and stabilise their elementome, namely stoichiometric homeostasis (H), is crucial for species adaptation in changing environments. Species can be stoichiometrically homeostatic to different degrees, and elemental homeostasis is related to species' nutrient economic strategies. Recent studies on N and P homeostasis have provided a framework linking plant fitness to ecosystem functioning. However, the mechanisms by which homeostasis of bioelements beyond N and P affects species performance and community functioning remain poorly understood, despite the well-established physiological functions of these bioelements. Based on 16 bioelements of 84 plant species from 232 wetlands, we found that bioelements with higher concentrations were more homeostatic in plants. Besides P, we further proposed that higher HK, HCa and HNa enhanced species biomass, dominance, stability and community biomass. Climate, nutrient supply, community elemental concentration and homeostasis coregulated community biomass of submerged plants. These findings expand the stoichiometric framework for predicting the adaptative mechanisms of plants and their communities to environmental changes.