坡耕地顺坡非均匀施肥对氮磷迁移及玉米生长的影响

Effects of Nonuniform Fertilization on Nutrient Transport and Maize Growth in the Sloping Farmland

[目的]分析坡耕地坡脚低肥、坡中中肥和坡顶高肥的顺坡非均匀施肥方式对土壤养分及玉米生长的作用,为坡耕地科学的施肥方式提供依据。[方法]通过布设野外径流小区和水样采集设备,观测了坡耕地土壤中氮磷迁移和玉米对养分的吸收。[结果](1)降雨后坡脚的土壤含水量最高,坡顶的土壤水分下降最快最多。(2)整个玉米生长周期内土壤水氮向坡脚浅土层处迁移,而土壤水总磷则呈峰值变化的趋势且以坡顶最为显著。(3)非均匀施肥下玉米生长对氮素的吸收以及干物质产量都较好,坡脚处的氮肥吸收率达到51.3%,磷肥吸收率达到25.5%。[结论]减少总施肥量的非均匀施肥方式能够保证玉米生长对肥料的吸收及产量,为我国坡耕地施肥方式优化提供参考。

[Objective]The aims of this research are to investigates the effect of nonuniform fertilizer in slope foot of low fertilizer,middle fertilizer and slope top of high fertilizer on soil nutrient and maize growth,and to provide a basis for the scientific fertilization method in sloping farmland.[Methods]Field runoff plot and soil water collection were designed to observe nitrogen and phosphorus transport and nutrient absorption by corn.[Results](1)Soil water content of slope foot was the highest and that of slope top had a fastest and largest decrease.(2)The nitrogen transported to shallow soil layer of slope foot,but phosphorus displayed peak value trends especially at the slope top.(3)A good nitrogen absorption in maize growth and dry material production were revealed under nonuniform fertilization,and nitrogen absorption rate at slope foot reached to 51.3%,and phosphorus absorption rate reached to 25.5%.[Conclusion]Nonuniform fertilization of decreasing total fertilizer amount ensures maize growth and yield,providing reference to optimize fertilization in sloping farmland of our country.