不同农艺措施组合对云南红壤坡耕地氮素平衡和流失的影响

通过对野外坡度为26.05%的径流小区实地观测,研究种植方式、施肥方式和等高植物篱条带3种农艺措施不同组合对云南红壤坡耕地氮素投入、带走平衡的影响.结果表明,在等高种植+平衡施肥+等高植物篱条带组合农艺措施条件下,收获玉米带走的氮为177.24 kg·hm-2,占水土流失和收获玉米带走氮总量的99.42%,水土流失带走1.03 kg·hm-2的氮,占水土流失和收获玉米带走氮总量的0.58%;顺坡种植+农民习惯施肥收获玉米带走的氮仅为120.31 kg·hm-2,占水土流失和收获玉米带走氮总量的79.36%,而水土流失带走31.29 kg·hm-2的氮,占带走氮总量的20.64%.等高种植比顺坡种植增加收获玉米带走氮素13.36 kg·hm-2,减少水土流失带走氮素18.53 kg·hm-2;等高种植和平衡施肥条件下,等高植物篱条带因占用少量土地而减少收获玉米带走氮素6.09 ks·hm-2,减少水土流失带走氮素5.73 kg·hm-2;顺坡种植和习惯施肥条件下,等高植物篱条带减少收获玉米带走氮素5.39 kg·hm-2,减少水土流失带走氮素29.97 kg·hm-2;平衡施肥比习惯施肥增加收获玉米带走氮素49.66 kg·hm-2,减少水土流失带走氮素6.00 kg·hm-2.云南红壤坡耕地氮素的平衡主要与氮肥、钾肥施用量和玉米籽粒、秸秆产量有密切关系,施氮量高,氮素投入高于带走;平衡施肥玉米籽粒、秸秆产量高,氮带走总量较多,氮素带走略高于投入;习惯施肥玉米籽粒、秸秆产量低,氮素投入高,带走较少.

Effect of Different Integrate Agronomic Measures on Nitrogen Balance and Loss of Red Soil on Sloping Farmland in Yunnan

Soil and water erosion, which highly related to improper farming, is a serious problem in Yunnan Province. A runoff experiment was conducted on a slopping farmland with a gradient of 26.05% in red soil area from 2004 to 2006 at Gaocang Village of Fumin County in Yunnan Province. Nitrogen(N)balance status between input and removal by corn and straw harvest, water and soil erosion were investigated in this experiment consisted of different cropping patterns, fertilization and contour hedgerow strip. The resul...