松花江流域非点源污染负荷估算与评价

结合RS和G IS技术,利用二元结构模型对2000年松花江流域非点源污染负荷进行计算与结果验证,并对流域内非点源污染状况做出评价。结果表明:4种非点源污染类型(农田、农村居民点、畜禽养殖和城市径流)中,农田TN、TP和NH₄⁺-N非点源污染负荷量最高;畜禽养殖COD非点源污染比重最大。流域TN、TP的非点源污染负荷大于点源的污染负荷,其中TP的非点源污染负荷远远超过点源;而NH₄⁺-N和COD的点源污染负荷则大于非点源污染。4种污染类型的不同污染指标(COD、TN、TP、NH₄⁺-N)在时间(2000年内)和空间上呈现出一定的分布规律。

Integrated Assessment of Non-point Source Pollution in Songhuajiang River Basin

On the basis of the opportunity of National Water Resource Planning in China,the loads of non-point source pollution were calculated in Songhuajiang River Basin in Northeast China in 2000.The work was finished by a model called binary structure model based on the data collection and investigation in the study area,additionally with the assistance of 3S technology.This model was set up by simplifying the process of pollutants transported of non-point source pollution.We divided the factors which affected the fate of pollutants into 2 categories;one is natural factors,the other social parameters.The most particular characteristic is that the dynamic factor,precipitation runoff factor was included in the equation.The model was applied in basin after calibration and validation.Then an assessment of non-point source pollution condition was presented.The results indicate: the load of TN,TP,and NH₄⁺-N almost came from agricultural fields(>70% for these 3 pollutants),but livestock and rural residential contributed the most COD load(>95%) among the 4 type′s pollution sources,i.e.,agricultural farm,livestock farm,rural residential areas and urban areas.The load of TN,TP resulted from non-point source pollution(about 61% of the sum) is larger than that from point pollution,in which the load of TP is about 10 times more than that from point pollution.The relationship between the loads of COD and NH₄⁺-N from non-point source and point pollution sources is opposite.The load of COD,TN,TP,and NH₄⁺-N from 4 type pollution sources presents a temporal and spatial characteristic in distribution.In general,the load transported during flood season(from June to September) is larger than that during drought period(December to next April).And the pollutants from non-point source pollution dispersed in the Songnen Plain in the Songhuajiang River basin and the Nenjiang River basin.