基于功能多样性的荒漠草原植物群落时间稳定性维持机制

荒漠草原生态系统抗干扰能力和自我恢复力较弱，降水和生物多样性是影响其植被恢复可持续性的主要因素。功能多样性作为生物多样性重要组成部分，直接参与和调控荒漠草原植被稳定性对降水变化的响应。理解功能多样性-群落稳定性维持机制，对荒漠草原退化草地自我调节能力和稳定维持具有重要意义。本项目拟以宁夏荒漠草原退化草地补播恢复后的7种群落为研究对象，通过改变降雨格局（增减雨30%、50%；自然降水），基于植物群落叶片和根系功能性状、地上生物量、土壤水分等指标，采用数学模型拟合分析方法，对不同植物群落地上和地下功能多样性、水分提取和利用、群落时间稳定性等展开研究，分析比较不同植物群落自我调节能力和时间稳定性差异；揭示影响群落水分提取和利用的关键功能性状指标；探明降雨变化条件下，植物功能多样性-群落稳定性维持机制。研究结果可为荒漠草原区模拟草地原生自然植被结构，构建一种可持续的植被恢复模式提供理论依据。

The ecosystem is weak in resistance and self-recovery, and precipitation and biodiversity are the two main key factors that affect the sustainability of vegetable recovery and reconstruction in desert steppe. Plant functional diversity, as an important component of biodiversity, direct involvement and regulation the stability of vegetation. Understanding the mechanism of functional diversity - community stability maintenance is of great significance to the self-regulation and stability restoration of degraded ecosystems in desert grasslands. In this project, seven plant communities will be selected as the objects, which were recovered by reseeding improvement measures. Based on plant community leaves and roots functional traits, aboveground biomass and soil water content, plant functional diversity of leaves and roots, water uptake capacity and effective availability, and the temporal stability of different plant communities will be analyzed by mathematical model fitting method. We aim to (ⅰ) analysis and compare the differences in self-regulation ability and stability of different plant communities; (ⅱ) reveal the key plant functional traits determining the water uptake capacity and effective availability; (ⅲ) explore the potential mechanisms of functional diversity affects plant community stability under precipitation change. Our findings will provide a scientific basis for mimic natural native natural vegetation structure of grassland to design a sustainable vegetation restoration models.