湖州平原河网区水环境容量计算研究

Calculation of the water environmental capacity for plain river network area of Huzhou

针对湖州东部平原河网区往复流水文特征,建立了基于正、负加权法的平原河网水环境容量计算模型,研究了90%水文保证率下COD和氨氮水环境容量。研究结果表明:90%水文保证率下湖州平原河网区COD和氨氮水环境容量分别为82262 t·a-1、4926 t·a-1;氨氮污染物排放入河量超过水环境容量现象较COD严重,按照COD和氨氮排放入河量现状,部分乡镇COD和氨氮入河量需进行削减后,才能基本满足相应的水环境功能区要求。

Based on the tide fluctuations,complicated hydrodynamic structure,the environmental capacities of plain river network area of Huzhou to assimilate COD and NH4+- N were studied using weighted water environmental capacity calculation model. The COD and NH4+- N water environmental capacity on the basis of 90% confidence instream flow in Huzhou plain river network area was 82262 t·a- 1and 4926 t·a- 1respectively. The river pollution load entering river body,calculated according to villages or towns,exceeded its water environmental capacity in some villages or towns. In order to make water quality met designated use,pollutant load reduction for COD and NH4+- N was necessary.