核素^(210)Pb_(ex)示踪法在小流域农业氮磷流失研究中的应用  

Estimation of Nitrogen and Phosphorus Losses Using ^(210)Pb_(ex) in a Small Watershed

作　　者：杨育红[1] 阎百兴[2] 严登华[3] 

机构地区：[1]华北水利水电学院水利学院,郑州450011 [2]中国科学院东北地理与农业生态研究所,长春130012 [3]中国水利水电科学研究院水资源研究所,北京100038

出　　处：《农业环境科学学报》2012年第10期1994-1998,共5页Journal of Agro-Environment Science

基　　金：国家"十二五"科技支撑计划课题(2012BAC19B03);华北水利水电学院高层次人才科研启动项目(001289)

摘　　要：利用210Pbex核素示踪和野外定位监测相结合的方法,通过研究吉林省长春市莫家沟小流域土壤流失厚度和土壤侵蚀模数,探讨土壤侵蚀与农业面源污染的输移关系,估算了农业面源颗粒态和水溶态污染负荷。结果表明,土壤流失厚度1.85mm·a-1,土壤侵蚀模数为2331t·km2·a-1,属于中度-强烈侵蚀水平;研究区单位面积年均输入水库的农业面源污染物总氮(TN)、水溶态总氮(WEN)、氨氮(NH3-N)、硝态氮(NO-3-N)、总磷(TP)、水溶态总磷(WEP)、磷酸盐磷(PO3-4-P)负荷分别为29、0.097、0.025、0.059、12、0.004、0.003kg·hm-2·a-1;土壤流失的TN、TP分别占多年平均化肥施用量的22%和10%。流失土壤携带的颗粒态TN、TP污染负荷分别是能被降雨径流浸提形成水溶态氮磷WEN、WEP污染负荷的300倍和3000倍。侵蚀流失的土壤颗粒是N、P流失的主要载体,也是最大的面源污染。Agricultural nonpoint sources pollution nutrient loads are closely related to soil erosion.Northeast of China is a key commodity grain base,and is one of the most important water erosion areas.The loads of particulate nitrogen and phosphorus（TN,TP）,and water extractable nitrogen and phosphorus（WEN,NH 3-N,NO 3-N,WEP,PO 34-P）were estimated using by 210 Pb ex nuclear tracing technique and field monitoring method.The annual mean erosion thickness was 1.85 mm·a^-1 at the Mojiagou watershed in Changchun City Jilin Province.The erosion intensity was 2331 t·km^-2 ·a^-1,classified to the moderate and severe degree transition section according to techniques standards for comprehensive control of soil erosion in the black soil region（SL 446—2009）.The fallout tracer technique of 210 Pb ex is feasible to quantify the soil erosion and the associated pollutants loads in Northeast of China.The annual mean values of pollution loads were TN 29 kg·hm^-2 ·a^-1,WEN 0.097 kg·hm^-2 ·a^-1,NH 3-N 0.025 kg·hm^-2 ·a^-1,NO 3-N 0.059 kg·hm^-2 ·a^-1,TP 12 kg·hm^-2 ·a^-1,WEP 0.004 kg·hm^-2 ·a^-1,PO 34-P 0.003 kg·hm^-2 ·a^-1,respectively.The particulate nitrogen and phosphorus loss rates per year with soil erosion accounted for 22% and 10% of the fertilizers applied,respectively.The particulate nitrogen and phosphorus loads were 300 times and 3000 times as that of water extractable nitrogen and phosphorus.Soil particles with soil loss were the main medium to transport nitrogen and phosphorus and the key nonpoint sources pollutants.

关 键 词：核素示踪法 土壤侵蚀 农业面源污染 中国东北 

分 类 号：X522[环境科学与工程—环境工程]