施氮对南疆潮土硝态氮分布的影响

Effect of nitrogen fertilizer on fluvo-aquic soil NO_3^--N distribution in Nanjiang

通过田间小区试验,对南疆潮土区不施氮、优化施氮和传统施氮下棉田土壤剖面NO3--N分布进行动态分析。结果表明:随施氮量的增加土壤剖面NO3--N的含量和下移深度增加;优化处理和传统处理在花期均随初花期追肥、灌水发生硝态氮淋溶,优化处理淋溶到60~90 cm,传统处理由于基肥用量过大可淋溶至150~180cm,说明基肥用量和第一次灌水是影响土壤硝态氮淋溶的主要因素。总体来说,优化处理施肥较合理,它在确保农民收益的同时能够兼顾环境。

The nitrate-N content and dynamic distribution in soil under different nitrogen fertilizer were monitored through field test. The result indicated that the content and moving depth of nitrate nitrogen increased with the increase of nitrogen fertilizer. During the cotton growth period, the leaching of nitrate nitrogen arrived in 60-90 cm in optimised treatment, whereas in traditional treatment it arrived in 150-180 cm in flow- ering stage because of superfluous base nitrogen fertilizer along with the irrigation in early flowering stage. That means the primary influence factors of nitrate nitrogen leaching are based on the nitrogen rate and first irrigation. Generally, the N apply rate of optimized treatment is reasonable because optimized treatment insure both the farmer＇s income and favorable environment.