黄土丘陵区地形微气候环境与植物功能性状响应

The importance of microhabitats in global biodiversity conservation has been highly recognized. Topography is an important controlling factor of microhabitats climate. Understanding the climate characteristics of topography controlled microhabitats is crucial to understanding the spatial vegetation pattern and ecosystem function in areas with complex terrain. However, research on the microhabitat climate in loess hilly region is lacking, and the importance of microhabitats in vegetation restoration are poorly understood. Thus, this study intends to take the Yanhe River catchment as a case study, and divide the whole study area into different bioclimatic zones to investigate the microhabitat climate change in loess hilly region. Within each bioclimatic zone, microhabitats will be selected depending on the terrain changes. Temperature, humidity and soil moisture will be measured to analyze the spatial and temporal variation of microhabitat climate and environment. Meanwhile, zonal temperature and humidity will be measured at different bioclimatic zones (on behalf of the regional climate) to detect the differences between microhabitat climate and regional climate. Then the decoupling of microhabitat climate from regional climate will be assessed. Plant species composition and leaf/root functional traits in each selected microhabitat will also be investigated, and the response of plant functional traits and their inter-correlation to microhabitat climate change will be analyzed, and adaptation strategy of different species and communities to microhabitat climate will be detected. Then a hierarchical model will be developed to detect the contributions of microhabitat climate and regional climate to the changes in plant functional traits and to reveal the mechanism of the formation and maintenance of vegetation pattern in complex terrain areas, providing the support for the conservation and recovery of biodiversity in loess hilly areas.

微生境在全球生物多样性保护与恢复中的重要性受到广泛关注。地形是微生境气候环境形成的重要基础，了解地形控制下的微生境气候环境特征，对于理解地形复杂区植被格局的形成与系统功能变化具有重要意义。研究针对黄土丘陵区微生境气候研究薄弱、微生境环境在植被恢复与生态保护中未受重视的现状，拟选择延河流域为研究区，区分不同的生物气候区（植被带），依地形变化，在每个生物气候区选择典型的地形微生境，测定温度、湿度及土壤水分，了解微生境气候环境的时空变化及其与区域气候变化的差异性，评估微生境在缓减环境气候变化影响中的作用；调查不同微生境下的群落物种组成，测定植物叶/根的关键功能性状，分析功能性状及其关系对微生境气候环境变化的响应，揭示物种和群落对微生境环境的适应机制；分析微生境气候与区域气候对植物功能性状变异的影响与贡献，揭示复杂地形条件下植被格局的形成与维持机制，为黄土丘陵地区的生物多样性保护与恢复提供依。

微生境在全球生物多样性保护与恢复中的重要性受到广泛关注。地形是微生境气候环境形成的重要基础，了解地形控制下的微生境气候环境特征，对于理解地形复杂区植被格局的形成与系统功能变化具有重要意义。本研究通过对不同地形条件下的57个样点的微生境的温度、湿度及土壤水分进行定量分析，了解微生境气候环境的时空变化及其与区域气候变化的差异性，评估了微生境在缓减环境气候变化影响中的作用，为全球气候变化背景下识别生物避难所（refugia），为物种多样性的保护提供数据支持；以植被功能性状为媒介，通过分析植物功能性状及其相关关系对微生境气候的响应规律，探究不同物种或群落对微生境环境的适应策略，阐明区域气候环境与微气候环境对区域植物功能性状变异的贡献，揭示了黄土丘陵区地形微生境的在群落构建中的重要性。同时,针对该区特殊的侵蚀环境（地形多变、环境复杂）特点，深入分析了群落物种多样性和功能多样性与微地形变化的关系；针对黄土高原植被恢复中以植被区划为基础而忽视局部的生境变化从而造成造林树种与立地环境的不匹配这一问题，对自然林分与人工刺槐林分布区的环境条件进行系统的比较分析。为黄土丘陵地区的生物多样性保护与恢复提供科学依据。