三峡工程的修建使得长江中游故道湿地景观格局发生显著改变，进而对湿地水环境质量产生重要影响。然而目前湿地景观格局与水环境质量的关系及其尺度依赖性还没有明确的结论，很难用于长江中游故道湿地景观格局变化及其水环境质量效应的评价。为此本项目拟以长江中游典型故道湿地为研究对象，一方面通过遥感手段获取三峡工程建设前后不同时期故道湿地景观格局及其变化特征；另一方面通过水样采集，结合采样期间遥感影像提取的景观格局特征，采用时间序列分析和直接梯度分析方法探讨多空间尺度景观类型及景观因子与水质的关系并识别影响水质变化的关键景观因子。在此基础上，建立不同空间尺度上关键景观因子与水质指标之间的模型，分析不同时期景观格局变化对水质的影响。这些工作的开展，将有助于明确三峡工程对故道湿地景观格局变化的影响，加深湿地景观格局对水质影响的机制理解，为缓解三峡工程对其下游生态环境影响提供科学依据。

The construction of the Three Gorges Dam (TGD) deeply influenced landscape pattern changes of oxbows in the middle reach of Yangtze River, which in turn have important effects on water environment quality. However, there is no common and clear conclusion on the relationship between landscape pattern changes and water quality and how it may vary across spatial scales. Thus, it is difficult to evaluate the effect of landscape pattern changes to water quality in the oxbows of Yangtze River. In this study, we select Tian'e-zhou and Hei-wa-wu oxbow of Yangtze River as our study area to (1) explore the variation of landscape pattern before and after the construction of TGD; (2) use time series analysis and direct gradient analysis to identify the key landscape factors on water quality. We will then establish the model between landscape pattern changes and water quality index to study the mechanisms. The results will help us better assess the influence of TGD to oxbows landscape pattern changes and its water environment quality effects, and will therefore offer a scientific support to ease the adversely effect of TGD to the ecological environment of the middle and lower reach of Yangtze River.