引用本文: | 韩龙飞,许有鹏,邵玉龙,石怡.城市化对水系结构及其连通性的影响——以秦淮河中、下游为例.湖泊科学,2013,25(3):335-341. DOI:10.18307/2013.0304 |
| HAN Longfei,XU Youpeng,SHAO Yulong,SHI Yi.Effect of urbanization on the stream structure and connectivity — A case study in the midlower reaches of the Qinhuai River. J. Lake Sci.2013,25(3):335-341. DOI:10.18307/2013.0304 |
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摘要: |
针对当前城市化所引起水系衰减、河流连通受阻以及由此所引起洪涝与水环境的问题,以秦淮河中、下游为例,选取1979和2006年两期流域遥感影像,分析了城市化影响下的下垫面变化特征;选取1980s和2009年的地形图对河流水系进行提取,借鉴景观生态学中河流廊道空间结构分析方法,通过不同时期水系分级,探讨了城市化对水系结构及其连通性的影响.结果表明:(1)城市化使得2006年城镇用地面积相比1979年增加84.54 km2,增加了9倍多,大量林草地、耕地以及水域转变成城镇用地;(2)河流长度在过去的30年里减少了41%,河道主干化趋势明显;河流发育呈现由多元到单一、由复杂到简单的趋势;(3)连通性参数连接率、实际结合度分别由原来的1.28、0.43下降到0.79、0.26,河流的连通性呈下降趋势.该研究将为城市化地区河流水系保护提供支持与参考. |
关键词: 水系结构 连通性 城市化 秦淮河 |
DOI:10.18307/2013.0304 |
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基金项目:国家自然科学基金重点项目(40730635);水利部公益性行业科研专项经费项目(201201072)联合资助 |
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Effect of urbanization on the stream structure and connectivity — A case study in the midlower reaches of the Qinhuai River |
HAN Longfei, XU Youpeng, SHAO Yulong, SHI Yi
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School of Geographic and Oceanographic Science, Nanjing University, Nanjing 210093, P.R.China
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Abstract: |
The effect of urbanization on the stream structure and connectivity has been a hot topic nowadays.At the present,fast urbanization has caused many enviromental problems,such as the decreasing of river numbers,rivers unconnected,water quality worsening,and frequent flood.The Qinhuai River watershed,mainly located in Nanjing City,Jiangsu Province,China,could serve as a good example.Two remote sensing images in 1979 and 2006 in mid-lower reaches of the Qinhuai River were processed and classified for the analyses on the spatial and temporal characteristics of underlying lands,which were the result of urbanization.The river systems were extracted based on the topographic maps in 1980s and 2009,and the influence on the stream structure and connectivity was discussed using a combination of stream grading and structure analysis methods on the river corridor in landscape ecology.Results show that: (1) Urban land has increased 9 times by 84.54 km2,and a large area of forest land has been transformed into urban land.Besides,paddy and dry land area were also decreased.Expanding of the urban areas of the city has invaded many other lands.(2) Length of the river has been decreased by 41% and the main river channel of the catchment are broadening.The stability of river has been declining and composition of the river system network was getting simpler.The stream stucture was developing from a complex model to a simple one.(3) Parameters of the river connectivity were both decreased.This explains why the rivers were not as well connected as 30 years ago and flood risk of this area current is high. |
Key words: Stream structure connectivity urbanization Qinhuai River |