CAJ | 학술논문

由于平原城市地貌起伏不大，较难划分城市河流的流域范围，使得与河道面源污染相关的研究范围的边界确定存在一定的困难。针对这一问题，本文对比了基于缓冲区和排水区的两种研究范围及方法。根据遥感影像，利用GIS提取研究区内土地利用信息并与河流水质进行回归分析，对比两种范围及方法所得出的结果，试图为城市河道污染物的研究及管理提供方法支持和理论依据。本文选取了天津滨海地区11条河流进行研究，结果表明：（1）选取城市排水区作为土地利用数据的方法能够与河流中污染物的发生，迁移的真实情况相符合，能够综合考虑不同的景观格局分布对于水质的影响，结合平原城市的特殊性反映土地利用与河流污染物之间的相关关系，在机理严谨性上优于使用缓冲区范围，在整体性上更为完整；（2）基于缓冲区的研究方法能够在一定程度上解释在地表径流作用下，河流近岸不同距离的土地利用类型对河流污染物的影响，如耕地对污染物的影响，河流近岸100 m缓冲区的联合显著性为0.848，300 m缓冲区的仅为0.165；（3）土地利用类型对河流中污染物类型的贡献和消减趋势基本一致，城市居民点与工矿用地是河流当中重金属污染物如铅、汞的主要输入源；耕地对重金属等污染物有一定的截留消减作用，但在面积较大时增加了河流的有机污染物如氨氮；林地、园地、草地和水体对于城市河流污染物有一定的净化作用。两种方法结合起来可以得出更为详尽、客观的研究结果。
유우평원성시지모기복불대，교난화분성시하류적류역범위，사득여하도면원오염상관적연구범위적변계학정존재일정적곤난。침대저일문제，본문대비료기우완충구화배수구적량충연구범위급방법。근거요감영상，이용GIS제취연구구내토지이용신식병여하류수질진행회귀분석，대비량충범위급방법소득출적결과，시도위성시하도오염물적연구급관리제공방법지지화이론의거。본문선취료천진빈해지구11조하류진행연구，결과표명：（1）선취성시배수구작위토지이용수거적방법능구여하류중오염물적발생，천이적진실정황상부합，능구종합고필불동적경관격국분포대우수질적영향，결합평원성시적특수성반영토지이용여하류오염물지간적상관관계，재궤리엄근성상우우사용완충구범위，재정체성상경위완정；（2）기우완충구적연구방법능구재일정정도상해석재지표경류작용하，하류근안불동거리적토지이용류형대하류오염물적영향，여경지대오염물적영향，하류근안100 m완충구적연합현저성위0.848，300 m완충구적부위0.165；（3）토지이용류형대하류중오염물류형적공헌화소감추세기본일치，성시거민점여공광용지시하류당중중금속오염물여연、홍적주요수입원；경지대중금속등오염물유일정적절류소감작용，단재면적교대시증가료하류적유궤오염물여안담；임지、완지、초지화수체대우성시하류오염물유일정적정화작용。량충방법결합기래가이득출경위상진、객관적연구결과。
As the plain urban area doesn’t show much difference in topography conditions, the usage of traditional river basin concept applying in plain urban area is not convincing. Thus, it’s hard to make an identification of effective border of the land use that can impact the relevant river water quality. To solve this issue, this paper compares the final results based respectively on the traditional buffer zone and drainage area method. Using 11 rivers’ pollutants in Tianjin Costal region and RS image, this paper apply GIS to study the correlation between land use and water quality by analyzing land use buffer data along the river banks and selecting land use data in drainage area, trying to provide methods and theories support to analyze and manage the rivers’ pollutants in plain urban area. The preliminary results showed that (1)The drainage area method can better illustrate the relationship between water quality and urban land use by taking full consideration of urban specialties such as water pollutant occurrence, movement and the impact of different landscape on water quality. It’s more theoretically convincing and comprehensive compared with the buffer zone analysis.(2)The buffer zone analysis can explain the influence on water quality under the effect of surface runoff to a certain extent. The negative correlation between the distance of buffer zone and the joint significance level can be used to identify the key area. For example, the joint significance level for arable land within 100 meters buffer zone is 0.848 and that number decreases to 0.165 as buffer zone expands to 300 meters. (3) Both methods show the same pattern for the relationship between water pollutant and land type. Urban construction land use will increase the water pollutant such as Pb and Hg;the arable land can reduce the heavy metal pollutant but will increase the organic pollutants such as ammonia as the area of arable land gets bigger;the grass land and water body will serve as the cleaner of the pollutants and help to improve the water quality. The combination of these two methods can help to get the result more objectively and comprehensively.