摘要
在云南抚仙湖流域尖山河典型小流域,建立标准径流场和微型小区,采用野外田间试验定点监测的方法,以坡耕地烤烟为研究对象,对其氮素平衡特征进行研究。结果表明:在坡耕地农田生态系统中,可溶态氮是天然降雨径流流失氮素的主要形态,其中硝态氮约占总氮的26.5%～75.2%;田面径流中氮素的含量随氮肥施用量的增加而升高,而氮肥施用强度与径流量具有一定的相关性;随着施氮量的增加,烤烟吸收氮的量由60.78kg/hm2上升至87.75kg/hm2,但吸收量与施肥量的比例由45.02%减小至25.91%,径流流失的量明显上升,严重影响了生态平衡以及对环境造成了很大的影响。
Nitrogen balance characteristics in typical small watershed basin sloping of flue-cured tobacco were analyzed by sentinel surveillance methods to nine micro-plots as the research object. The results showed that：field surface runoff of nitrogen content was increased with the amount of nitrogen fertilizer; soluble nitrogen is a natural rainfall-runoff loss of the main form of nitrogen in sloping farmland ecological system,which accounts for about the total nitrate nitrogen,26.5%-75.2%; intensity and nitrogen fertilizer runoff has certain relevance. With the amount of nitrogen increases,the amount of flue-cured tobacco gradual increase in absorption of nitrogen but there are certain restrictions. With the amount of nitrogen increases,the amount of flue-cured tobacco to absorb nitrogen increased by 60.78 kg/hm^2 to 87.75 kg/hm^2,but the absorption and the ratio of fertilizer decreased from 45.02% to 25.91%,while the nitrogen was lost as runoff a clear upward trend,which it will have a negative impact in sloping farmland ecosystem nitrogen balance and eutrophication of water environment.
出处
《水土保持学报》
CSCD
北大核心
2010年第1期150-154,共5页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(30660037)
云南省自然科学基金项目(2006D0041M)
云南省科技计划项目(2006SG20)
关键词
氮素平衡
烤烟
坡耕地
滇中
sloping filed
flue-cured tobacco
nitrogen balance
the middle Yunnan
