城市湿地小流域尺度景观空间分异及其对水体质量的影响——以南京市紫金山东郊典型湿地为例  

Impacts of landscape heterogeneity on water quality of urban wetlands at sub-watershed scale:a case study on the eastern suburb of Nanjing

作　　者：郝敬锋[1] 刘红玉[1] 胡俊纳[1] 李玉凤[1] 郑囡[1] 

机构地区：[1]南京师范大学地理科学学院,江苏省环境演变与生态建设重点实验室,南京210046

出　　处：《生态学报》2010年第15期4154-4161,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(40871084;40701174);青蓝工程项目(184080H10240)

摘　　要：综合利用遥感、GIS技术、景观生态和实验分析方法,选择南京市紫金山东郊17个典型湿地,在2008年3月至2009年3月期间进行野外湿地水体水质监测。以每个湿地所在的小流域为景观单元,通过SPSS系统聚类分析将17个小流域划分3类,揭示城市化影响区域小流域土地利用特征及其对湿地水体质量影响,结果表明:(1)城市土地利用对湿地水质影响显著。以林地斑块为主要景观类型的小流域水质比以草地斑块为主的小流域水质好,林地面积越大,湿地水质越好;(2)通过引入增强斑块指数ZQI、削减斑块指数XJI、及增强-削减斑块对比指数R_ZXI,进一步揭示小流域内景观格局与水质之间的相关关系。研究表明,当R_ZXI小于-1时,随着R_ZXI的增加,一些易流失营养型污染物质TN、CODMn呈下降趋势,而当其大于-1呈上升趋势;一些易沉积营养物质如TP则表现出相反变化趋势;(3)小流域内各景观斑块空间上分布越均匀,湿地水体中的易流失营养型污染物质表现出下降趋势,而易沉积型营养物质则表现出上升的趋势。Urban wetland is an important part of urban landscape.Its ecological function plays a significant role in the development of urban eco-environment.But,with a rapid expansion of urban land and citizenry on the eastern suburb of Nanjing,most of wetlands lost.As results,landscape surrounding each remnant wetland has been changed.In this study,based on remote sensing and GIS techniques,the landscape heterogeneities were identified at sub-watershed scale for 17 wetlands in the eastern suburban of Nanjing.Farther more,these 17 sub-watersheds were divided into three classes that can best explain land use characteristics by clustering analyses of SPSS.The collection of samples for water quality analysis was performed in March,2008 to March 2009,and samples were collected in 17 wetlands once a month.Our research results found that：① land use of urban wetland impacted water quality prominently.Higher percent forest cover was associated with better water quality.② the index of ZQI（Increased patch）,XJI（Decreased Patch）,R_ZXI（contrast of ZQI and XJI） was related to higher water quality.R _ZXI increase were associated with decrease of Total nitrogen（TN） and Chemical Oxygen Demand（COD） when R_ZXI〈 -1;and R_ZXI increase were associated with increase of TN and COD when R_ZXI 〉-1.However,the total phosphorus（TP） change exhibited opposite to TN.③ Evenness of landscape for wetlands were also related to water quality.Higher evenness were associated with lower TN,CODMn,and it＇s opposite to TP.

关 键 词：城市湿地 景观空间分异 水质 南京市 

分 类 号：X37[环境科学与工程—环境工程]