城市非点源污染控制的景观生态学途径

城市非点源污染是伴随城市快速发展而出现的新问题.城市土地利用的特殊性、不透水层面积的增加,使城市非点源污染不同于农业非点源污染,而控制难度更大.治理城市非点源污染的常用方法是最佳管理措施(Best Management Practices,BMPs),主要采取一些局部修复措施在地表径流迁移过程中控制污染物.但城市土地利用格局的改变对非点源污染的影响十分显著,结合局部的BMPs和区域的景观规划是控制城市非点源污染的一个理想途径.城市非点源污染控制的景观生态学途径首先需要了解城市景观格局对非点源污染源、污染物迁移过程和受纳水体的影响,明确非点源污染与景观格局的关系,判定造成非点源污染的主要原因和关键环节.在此基础上,根据城市非点源污染控制要求,针对性地重新组合原有景观格局或引入新的景观要素以构建新的景观格局,并将BMPs融入规划之中,将景观规划与管理有机结合,增强城市景观异质性,实现对城市非点源污染的有效控制.

A landscape ecological approach for urban non-point source pollution control

Urban non-point source pollution is a new problem appeared with the speeding development of urbanization.The particularity of urban land use and the increase of impervious surface area make urban non-point source pollution differ from agricultural non-point source pollution,and more difficult to control.Best Management Practices (BMPs) are the effective practices commonly applied in controlling urban non-point source pollution,mainly adopting local repairing practices to control the pollutants in surface runoff.Because of the close relationship between urban land use patterns and non-point source pollution,it would be rational to combine the landscape ecological planning with local BMPs to control the urban non-point source pollution,which needs,firstly,analyzing and evaluating the influence of landscape structure on water-bodies,pollution sources and pollutant removal processes to define the relationships between landscape spatial pattern and non-point source pollution and to decide the key polluted fields,and secondly,adjusting inherent landscape structures or/and joining new landscape factors to form new landscape pattern,and combining landscape planning and management through applying BMPs into planning to improve urban landscape heterogeneity and to control urban non-point source pollution.