甘肃河西绿洲灌区农田耕层土壤养分调查与评价

Investigation and evaluation of nutrients in surface soil of farmland in Hexi oasis irrigation area of Gansu Province

【目的】明确甘肃河西绿洲灌区农田土壤养分的空间分布现状,有助于制定合理的施肥策略和实现该地区农业生产的可持续发展.【方法】通过GPS定点采集2011年和2017年0~20 cm耕作层土壤样品,调查分析河西绿洲灌区土壤养分现状.【结果】甘肃省河西绿洲灌区土壤偏碱性,全氮与有机质含量较低,速效磷与速效钾含量中等偏上.总体表现为,武威市与张掖市的土壤养分含量优于酒泉市与金昌市,随着耕种时间的推进,酒泉市土壤有机质下降趋势明显,张掖市的民乐县与武威市的天祝县土壤全氮、有机质、速效磷与速效钾均呈增加趋势,土壤肥力维持较好.【结论】建议在酒泉市与张掖市的甘州区、临泽县、山丹县及金昌市金川区,增施有机肥或秸秆还田,氮肥以追施为主,适量补充磷钾肥,通过优化土壤理化性质,改善土壤肥力状况,增强土壤的可持续性.

【Objective】To clarify the contents of soil nutrients of farmland in Hexi oasis irrigation area of Gansu Province in order to establish proper fertilization strategy for high yield and quality crop production and sustainable development of agriculture.【Method】Soil samples of fixed points in 0~20 cm soil layer were collected in 2011 and 2017 to investigate and analyze the soil nutrient status in Hexi oasis irrigation area.【Result】The soil was alkalescence,the contents of total nitrogen and organic matter were low,while the contents of available phosphorus and potassium were in medium high level.In general,the soil nutrient contents in Wuwei and Zhangye cities were higher than that in Jiuquan and Jinchang cities.The content of soil organic matter in Jiuquan City showed an obvious decreasing trend with the cultivation time.However,the contents of soil total nitrogen,organic matter,available phosphorus and available potassium was increased in Minle and Tianzhu counties,and the soil fertility was well maintained.【Conclusion】The recommended fertilization maintenance strategy is organic fertilizer application or straw-returning,and the nitrogen fertilizer should be mainly topdressed with proper supplementary phosphorus and potassium fertilizers in Ganzhou District,Linze County,Shandan County of Zhangye City,and Jinchuan District of Jinchang City.