Cause analysis on spatial distribution of sewage entering rivers in typical industrial city located at delta area

Based on the first national census data of pollution sources of Dongguan City,a typical industrial city in delta area,the spatial distribution characteristics of sewage entering rivers and its influential factors of Dongguan City in 2010 are analyzed.The study shows that the sewage discharge from the towns of Dongguan City is distributed unevenly;the sewage discharges from economically developed towns and the towns in Dongjiang River network area are very concentrated and have a general tendency of larger sewage discharge in downstream area;the main influential factors are GDP,pollution industry and geographic location.In the meantime,the unit GDP sewage discharge in river network area is larger than that in non-river network area,showing that the economy in river network area developed at the cost of environment.The basic causes of severe pollution in river network area are rich water resources,convenient water taking condition,concentrated pollution industries,resulting in extensive water use and severe industrial sewage pollution.