植物与水分关系一直是生态水文学研究的核心内容。在干旱沙区，固沙植物对水分的敏感性使得植物动态与水分利用之间关系的研究成为人们关注的重点。目前国内外相关研究主要从生理生化的角度探讨了植物的水分利用特征及其对干旱胁迫的响应机理，而从植物个体形态调整对土壤水分的适应阈值方面研究较少。本研究以沙坡头地区不同配置的固沙植物柠条和油蒿为研究对象，通过试验和模拟的方法，量化不同固沙植物的生长动态及其与土壤水分相互作用的各个环节；建立随机生态-水文模型，模拟分析植物的生长发育及其季节性变化对水文过程的响应与适应，确定固沙植物形态调整的土壤水分阈值范围；揭示沙区随机降雨模式下的植物-水分相互作用机制。项目的研究成果不仅可以进一步丰富我们对植物与水分关系的认识，还可以为沙区人工植被恢复与重建后的植被稳定性及其变化趋势评价提供理论依据。

Plant water relations has always been the core content of eco-hydrology. In the arid desert area,theoretical studies on the relationship between plant dynamics and water use have received increasing interests in recent years because of the sensitivity of the sand-fixation plantations on soil water. Many researches have explored the plant water use and its response to drought stress from the perspective of ecophysiology, but less work has been done based on the morphological adjustment threshold of individual desert shrubs towards variation in certain range of soil moisture. The present study takes the typical sand fixing plants community of Caragana korshinskii and Artemisia ordosica as our research object in the Shapotou area. Through experimental and simulative study, we aimed to (1) study the soil water dynamics and the mechanism of morphological adjustment relating the response of aboveground part and roots of plant to soil moisture variations,(2) construct the stochastic eco-hydrological model to simulate the responses of plant growth and its seasonal dynamics to hydrological processes, and further to determine the soil moisture threshold of plant morphological adjustment, and (3) explore the mechanisms of plant water interaction under random rainfall events. The results of this project would be expected to not only improve our understanding on the plant - water relationships, but also provide scientific and technological support for the evaluation of vegetation stability and its succession trends after revegetation in the western arid desert regions.