补水景观湖水生态系统构建对水质的影响及因子分析

以广州市最大补水人工景观湖白云湖水生态系统构建示范区为对象，利用综合污染指数评价了以沉水植被构建为主的修复措施对示范区水体水质改善的影响，并应用因子分析法对各水质指标和生态因子之间的相互关系进行了研究。综合污染分析结果表明，恢复沉水植物后，示范区水体各项污染物浓度大幅降低，水质从V -劣V类提高到Ⅲ-IV类，水体综合污染状态由严重污染改善为轻污染。因子分析显示，10项水质指标可划分为四类主因子来反映水质状况，其中，第一主因子主要反映水体营养盐指数，第二主因子反映水体有机污染指数，第三主因子反映温度变化对水质的影响，第四主因子反映水体的酸碱度；综合评分结果说明了生态系统构建后水质综合评分可大幅降低，且月评分结果呈现温度越高、水质越优的特点，水体特征呈现向草型水体发展的趋势。上述结果表明，水生态系统构建可有效改善示范区水质，是保障城市河道补水水源安全的有效方法。

Effect of aquatic ecosystem reconstruction on water quality of landscape lake of water supplement purpose by factor analysis

The effect of submerged aquatic-vegetation based restoration on water quality of Baiyun Lake Ecological Demonstration Area,which was the largest landscape artificial lake of water supplement purpose in Guangzhou City,was evaluated by using comprehensive pollution index.Results showed that,as the development of submerged vegetation,the water quality was improved from grades Ⅴ or worse than grades Ⅴ to grades Ⅲ or Ⅳ of state water quality standards for surface water,and the comprehensive pollution status changed from serious pollution to mild pollution.In addition,factor analysis was used to investigate the relationship between water quality and ecological factors.Ten water quality indicators were classified into four categories to reflect the water quality.The first factor contained the information of nutrient index.The second factor provided the information of organic pollution.The third factor was mainly about influence of temperature on water quality.And the forth factor was related with pH value.The comprehensive score based on factor analysis was greatly reduced after the ecology system was set up.And the monthly score throughout the year manifested as the higher temperature,the better water quality,which may be a trend towards a macrophytic lake.In summary,aquatic ecosystem reconstruction can improve the water quality of demonstration area significantly,and may be a feasible solution to ensure the safety of urban river water supplement.