西藏一江两河农田土壤氮、磷变化动态分析

Farmland Soil Nitrogen and Phosphorus Dynamic of One River and Two Streams in Tibet

环境问题是我国亟待解决的重大问题,农业面源污染是我国所面临的环境问题之一。一江两河流域是我区主要的粮食生产基地,由于我区一江两河流域氮、磷肥使用量在不断增加,使氮素、磷素在土壤中不断积累,同时也增加了氮、磷的流失风险。本文主要对西藏一江两河流域农业主产区拉萨市(墨竹工卡县、达孜县、曲水县)、山南市(贡嘎县、扎囊县、乃东区)、日喀则市(江孜县、白朗县、桑珠孜区)农区农田土壤进行样品采集,分别采用了凯氏蒸馏法和钼锑比色法测定了全氮、全磷的含量,并通过实验数据进行分析和讨论,分析2015年与2016年土壤氮素、磷素动态变化,从而判断一江两河流域农业面源污染的风险性。

Environmental problems,such as agricultural non-point source pollution is one of the environmental problems facing in our country.One River and Two Streams Basin in Tibet is the major area of agricultural production,with the increasing of N,P fertilizer usage,the accumulation of N and P in the soil may lead to the dangrous loss of N and P.The farmland soil samples in Tibet like agriculture producing Lhasa(Maizhokunggar,Dazi and Qushui),Shannan(Gonggar,Zhanang,Naidong),and Xigaze(Jiangzi,Bainang,Sangzhuzi Rigion)were collect,and T-N and T-P were determinated by distillation and molybdenum antimony colorimetric method.The experimental data of N and P was analyzed,and to discuss linear correlation of dynamic changes of soil N and P in 2015 and 2016,therefore,the cause of agricultural non-point source pollution was to be judged.