中文摘要：

经分析历史数据资料和2005-2006年现场调查数据，全面探讨长江口青草沙水源地开发的生态环境影响。研究结果表明：青草沙水域水质总体良好，主要水质指标满足地表水Ⅱ类标准；陆域植被分布面积11.3km^2，常见植物种类22种，以芦苇、菰和青蒿为主；水域水生生物多样性较高，水生生物生态类型主要以淡水性和趋淡水性为主；在流域污染排放与上游来水水质、重大工程建设与河口咸潮入侵等环境变化背景下，青草沙水源地开发将对库区水环境以及周边生态环境产生不同程度的影响，建议关注水库运营优化、水源保护区划定、环境污染控制和生态环境补偿等保护策略。

英文摘要：

Based on historical and 2005 - 2006 field survey data, environmental impact assessment of Qingcaosha Reservoir construction project in the Yangtze Estuary was carried out. Resuits show that water quality in Qingcaosha is good, and the main indicators of water quality can meet the class Ⅱ of national surface water standard. There are 22 common types of plants in the study area with a vegetation cover of 11.3km^2. The aquatic biodiversity is high, and freshwater species are the main types of aquatic ecology. River basin pollution emissions, upstream runoff water quality deterioration, major construction projects and estuarine saltwater invasion may impact water quality of the reservoir. Reservoir operations optimization, delineation of source water protected areas, environmental pollution control and compensation strategy should be taken to protect the Qingcaosha area.