胥彦玲¹,李怀恩¹，倪永明²,扬帆³

（1西安理工大学环境科学研究所西安，2北京自然博物馆 北京，3西安科技大学地质与环境工程系,西安）

摘要：为有效控制黑河流域因土壤侵蚀而产生的氮、磷非点源污染,改善黑河水库水质,以流域的行政单元作为估算非点源污染的响应单元,利用通用土壤流失方程并选取合适的方法进行了参数选取和率定,在软件辅助下,估算了各单元的土壤侵蚀虽,计算了流域吸附态氮磷的污染负荷。结果表明：

（1）文中所用估算方法较为合理,全流域的平均侵蚀模数为315.06/(km2.年)；

（2）流域每年由土壤流失所引起的吸附态氮磷总负荷量分别达到15.702t和3.866t。对流域水环境造成了严重的污染和破坏；

（3）马召乡、甘浴湾乡、板房子乡、安家岐乡、厚吵子乡以及小王涧乡对流域氮磷污染负荷贡献较高,是流域非点源污染控制的主要源区；

（4）退耕还林还草,增加植被覆盖度,减少农事活动是削减和控制流域非点源污染的主要措施。

Abstract: To control effectively non-point source pollution and improve reservoir water quality in Heihe watershed ,taking regionalism as estimate unity ,this paper estimates soil losses of unity using USLE and selecting right method to calibrate parameter by GIS software.Then the loadings of absorbed nitrogen and phosphorous are calculated.The results shows:

1)The estimate means is reasonable ,and the average erosion modeulus is 315.06t/(km².a) .

2)the adsorptive nitrogen and phosphorus loadings are 15.702 ton and 3.866 ton respectively,which pollute and destroy water environment greatlu.

3)Mazhao village ,Ganyuwan ,Banfangzi,Anjiaqi,Houzhenzi and Xiaowangjian village contribute more nitrogen and phosphorus loadings.They are the key source area of non-point source pollution control.

4) Returning land from farming to forestry and grass ,increasing vegetation cover and decreasing farming activity are the main measures of reducing and controlling non-point source phosphorus pollution.

key words :water and soil loss; USLE ;nitrogen and phosphorus loading ; Heihe river watershed

西北农林科技大学学报2006.3