中文摘要：

基于波段组合指数与单波段特征相结合的方法对九龙江流域城镇建设用地进行提取,并采用景观生态学与统计分析方法,分别对流域内城镇建设用地的面积百分比及景观格局指数与水体中的高锰酸盐指数、NH 4＋-N、TP浓度变化之间的关系进行研究.结果表明,流域内城镇建设用地的面积百分比与高锰酸盐指数、NH 4＋-N、TP呈现显著正相关（r为0.701、0.695、0.789）,城镇建设用地的最大斑块指数（LPI）与高锰酸盐指数、NH 4＋-N、TP浓度呈现显著正相关（r为0.555、0.643、0.722）,城镇建设用地的景观形状指数（LSI）与高锰酸盐指数、TP浓度呈现正相关（r为0.564、0.553）,说明城镇建设用地对水质的影响不仅与其在流域内的面积比例有关,而且与其空间格局关系密切.季节性关联分析发现,随着城镇建设用地的增多,在丰水期和枯水期的水质恶化过程较快,是水华易发的敏感时期;各小流域的水环境质量处于受影响状态,位于九龙江源头的龙门溪、苏溪、小溪流域城镇建设用地比例较高（9%～16%）,需及时进行城市化进程的调整和控制.

英文摘要：

Band grouping indices combined with single band characteristic were used to extract urban built-up land based on satellite image in the Jiulong River Watershed.Landscape ecology method and statistical analysis were employed to explore the relationship between urban built-up land and permanganate index,NH＋4-N,TP concentrations.There were significantly positive correlations between the proportion of urban built-up land and permanganate index,NH＋4-N,TP（r= 0.701,0.695,0.789）.It indicates the proportion of urban built-up land areas in the sub-watershed could be an effective indicator of water quality.The largest patch index（LPI） was positively correlated to permanganate index,NH＋4-N,TP concentrations in the water（r=0.555,0.643,0.722）.The landscape shape index（LSI） was positively correlated to permanganate index and TP concentrations in the water（r=0.564,0.553）.These means the impacts of urban built-up land on water quality are influenced not only by urban built-up land areas but also by spatial patterns.The seasonally linear correlation results show that water quality deteriorates quickly with urban built-up land during the flood season and dry season,and the water is susceptible to eutrophication in both flood and dry seasons.The water quality in most sub-watersheds are impacted by urban built-up land,while the urban built-up land areas of Longmen stream,Su stream and Xiao stream located in headstreams are intensive,which need to be adjusted and controlled to protect the water quality.