保水材料对河套灌区土壤硝态氮和铵态氮动态变化的影响

为了研究内蒙古河套灌区农业化肥面源污染检测和治理措施,采用大田土壤淋溶试验,分析了河套灌区农田在保水材料处理下,玉米生育期内土壤硝态氮、铵态氮累积量及动态变化特征。结果表明,与CK相比,保水材料处理玉米苗期土壤NO_3~--N累积量平均提高20.49%,收获期平均降低13.98%;苗期土壤NH_4~+-N累积量平均提高35.21%,收获期平均降低28.93%。保水材料有效地抑制了氮素的淋溶损失,提高了氮素利用率,同时保证了玉米生育后期有效氮的供应,避免短时间内氮素的大量累积,在一定程度上减少了化肥面源污染,为农业面源污染治理提供有力措施。

Effect of Water Retaining Material on Soil Nitrate Nitrogen and Ammonium Nitrogen Dynamic Change in Hetao Irrigation Area

To study non-point source pollution detection and control measures of Hetao irrigation area of Inner Mongolia agricultural,chemical fertilizer field soil leaching tests were used and soil nitrate nitrogen and ammo-nium nitrogen dynamic change in the Hetao irrigation farmland under the water-retaining material processing were analyzed.The results showed that water-retaining material could effectively adsorb NO3--N and NH4+-N leaching amount in shallow soil and it could reduce nutrient leaching.So it had the protecting of fertilizer ap-plied delay effect.Compared to CK,soil NO3--N accumulation amount of water-retaining material processing treatments increased by 20.49%in corn seedling period,but increased by 13.98%on average in the harvest peri-od;Soil NH4+-N accumulation amount increased by 35.21%on average,but increased by 28.93%on average in the harvest period.Water-retaining material effectively inhibited nitrogen leaching losses and improved the utili-zation rate of nitrogen.At the same time,it could guarantee the effective nitrogen supply of following corn stage and avoid a large number of accumulations in a short time.So to a certain extent,water-retaining material reduc-es the fertilizer non-point source pollution and provides the effective measures for agricultural pollution control.