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作 者 ：冯兆忠,王效科,冯宗炜,刘宏云,李延林

期 刊 ：生态学报 2003年 23卷 10期 页码：2027~2032

关键词：秋浇；土壤NO_3-N；淋失量；农田类型；河套灌区；

Keywords:autumn irrigation, NO 3 N in soil profile, leaching amount, farmlands, Hetao i rrigation district,

摘 要 ：研究了河套灌区秋浇对不同类型农田 NO3 - N淋失的影响。结果表明 ,秋浇前小麦和白菜地 NO3 - N含量最高 ,玉米地和小麦 -玉米套种地次之 ,葵花地最低。秋浇后土壤剖面 NO3 - N的损失量按照表层 (0～40 cm)、中层 (40～ 80 cm)、深层 (80～ 1 2 0 cm)依次递减 (玉米地除外 )。不同农田 NO3 - N淋失量按照小麦地、白菜地、玉米地、葵花地、小麦 -玉米地依次递减。这说明 ,发展套种耕作将有利于减少氮素淋失。土壤 NO3 -N的淋失还直接导致地下水质的恶化。在当前的耕作制度及秋浇定额下 ,河套灌区每年可损失约 2 .6× 1 0 7kg N。因此 ,需要科学地确定秋浇方式和秋浇量 ,减少氮素淋失 ,减少地下水污染。

Abstract:Autumn irrigation is a particular irrigation system, which washes salt to deeper soil profile and keeps higher soil water content for cultivating next spring cr ops in Hetao Irrigation District of China. Autumn irrigation occurs during the n on-growing season and may cause leaching of any nitrates left in the soil profi l e. However, this nitrate leaching has been rarely paid attention. The paper is a imed to determine and compare the effects of autumn irrigation on soil nitrate l eaching among different fa...

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