毛乌素沙地油蒿灌丛空间自组织格局及其生态水文响应机制

干旱半干旱区人类活动在增强，希望通过植被恢复改善生态环境，但却产生了土壤干化、地下水位下降等负面生态效应，这主要是由于植被恢复过程中没有考虑植被空间格局与生态水文的关系。油蒿是毛乌素沙地最重要的固沙植物，弄清其植被空间格局的生态水文响应机制是该地区植被恢复的基础和核心科学问题。项目针对毛乌素沙地油蒿灌丛生态系统，通过野外调查，分析油蒿灌丛空间自组织格局特征，利用定位观测和模型模拟等手段，分析油蒿灌丛植被蒸腾耗水和土壤水分动态，探索油蒿灌丛空间格局与土壤水、蒸腾耗水等生态水文过程的关系，揭示毛乌素沙地油蒿灌丛空间自组织格局特征及其生态水文响应机制，耦合植被空间格局与植物蒸腾和土壤水的关系，构建并验证生态水文模型，优化和修正模型参数，深刻理解油蒿灌丛空间格局对植被耗水与土壤水的作用机制，并基于改进的Brook90模型，模拟并评估植被空间格局变化的生态水文特征，指导植被恢复与水资源的合理调控。

The human activities are enhancing in the arid and semi-arid region, we expect that the ecological environment can be improved through vegetation restoration, but it induced some negative ecological problems to exacerbate the regional water contradiction, such as the soil dry layers, water level dropping and reducing the runoff, and this is mainly because there did not consider the relationship of vegetation spatial pattern and ecohydrological processes in the vegetation restoration.Artemisia ordosica is an important species that fixed the sands in Mu Us sandy land. Understanding the ecohydrological response mechanism of spatial pattern of vegetation is a very important and key scientific problem for vegetation restoration in the area. By field observation, the project will analyze the characteristics of vegetation spatial self-organized pattern. And then the vegetation transpiration and soil moisture dynamics will be observed by field fixed observation and modeling to explore the relationship of shrub spatial pattern and ecohydrological processes, such as soil moisture and transpiration. The project will reveal the spatial self-organized pattern of Artemisia ordosica shrub and its ecohydrological response mechanism, and couple the relationships of vegetation spatial pattern and ecohydrological processes and validate the ecohydrological model and understand profoundly the mechanism of spatial pattern and ecohydrological processes. Based the Brook90 ecohydrological model, the project will simulate and evaluate the characteristics of soil moisture and evapotranspiration under the different vegetation spatial pattern scenarios to guide water resource regulation and vegetation restoration, such as the spatial distribution and densities in the vegetation restoration.