基于有限资料的水土流失区非点源污染负荷估算

The Non-point Source Pollution Loads Estimation Method in Limited Data of the Soil and Water Loss Region

依据多沙河流的非点源污染特点,结合河流床沙中的污染物含量与流域内表层土壤污染物含量间的关系,提出了基于有限资料条件下的水土流失区非点源污染负荷估算方法,并以渭河流域华县断面为例进行了实际应用,结果表明:该法简单易行,资料需求程度不高,计算结果合理,可用于水土流失区非点源污染的初步估算;渭河流域华县断面非点源污染总磷负荷与汛期输沙量相关程度最高,达到0.91,而氨氮和硝酸盐氮分别为0.77和0.75,相对较弱;渭河流域华县断面丰沙年输出氨氮53 304 t、硝酸盐氮18 878 t、总磷237 387 t;而平沙年、枯沙年分别输出氨氮26 796 t,9 204 t,硝酸盐氮10 444 t,4 847 t,总磷144 431 t,82 740 t。

According to the non-point source pollution characteristics of sediment-laden river,combining with the pollutant content relation between the river bed sediment and inner drainage area surface soil, advising the non-point source pollution loads estimation method of soil and water loss region in limited data direction and applying the method in Huaxian section of the Weihe River Basin. This method is simple and practicable, the requirement of data is less so the method can be applied for elementary estimation in soil and water loss region. The research shows： The correlation degree between total phosphorus load of non-point source pollution and flood season sediment discharge is highest and is 0. 91 in Huaxian section of the Weihe River Basin, the correlation degree between ammonia nitrogen and flood season sediment discharge is 0. 78 and the correlation degree between nitrate nitrogen and flood season sediment discharge is 0.77. In high sediment concentration year, the ammonia nitrogen output is 53 304 t, the nitrate nitrogen output is 18 878 t and total phosphorus output is 237 387 in natural and low sediment concentration year, the ammonia nitrogen output are respective 26 796 t and 9 204 t, the nitrate nitrogen output are respective 10 444 t and 4 847 t,the total phosphorus output are respective 144 431 t and 82 740 t.