Experiment on Nitrate Nitrogen Transport and Transformation in Saline Soil under the Irrigation-Drainage Condition in Arid Inland Basin

Groundwater and surface water have been threaten by nitrate nitrogen pollution because of the increasing of agricultural fertilizers. In this paper, we studied on nitrate nitrogen transport and transformation in soil under the irrigation-drainage condition in arid inland basin through a longtime field test. The study has draw conclusions as following: 1) The irrigation has a great impact on groundwater level and the amount of agricultural drainage. The ratio between drainage and irrigation is 53.77% in 2003 in test plot. Flood irrigation has a threat to Bosten Lake because which will produce a lot of agricultural drainage and take a lot of inorganic salt and nitrogen. 2) Initial concentration and lithology of soil have a great influence on transport and transformation of nitrogen. 3) Concentration of nitrate nitrogen below 100 cm is much higher than background concentration, so it shows that nitrate nitrogen is main pollutant of nitrogen under irrigation-drainage condition.