摘要
采用野外田间试验定点监测的方法,通过研究滇中坡耕地地表径流中氮素流失的形态和浓度来反映氮素动态变化特征。结果表明：雨季氮素输出主要以径流为主,占流失量的64.86%。相同降雨条件下,不同处理三氮浓度均值均表现为：CK〈N1〈N2〈N3〈N4〈N5,N5处理总氮和硝态氮浓度最高值达到5.52,4.36 mg/L,高出其他各处理的2.85-4.69倍和4.73-10.45倍,铵态氮浓度介于0.01-1.30 mg/L之间。滇中坡耕地地表径流输出主要以可溶态为主,可溶态氮中以硝态氮为主,硝态氮占全氮浓度比例为21.02%-83.55%,铵态氮仅占总氮的1.02%-38.58%。氮素各形态浓度与施肥量之间、总氮浓度与氮素输出量之间、施肥量与氮素输出量之间存在显著的线性关系,相关系数达到0.864 1-0.983 8。
Sentinel surveillance methods was conducted to study overland runoff patterns and concentrations of nitrogen loss in sloping filed in the middle regions of Yunnan province,it could reflect the dynamic changes feature of nitrogen.The results showed that： runoff nitrogen export was the main pattern in the rainy season;it was accounted for 64.86 percent.The mean TN,NO-3-N,NH＋4-N concentration of different treatments in the same rainfall conditions were expressed：CKN1N2N3N4N5.The highest TN,NO-3-N concentration of N5 treatment reached 5.52,4.36 mg/L,they were higher 2.85~4.69 times and 4.73~10.45 times than other different treatments,NH＋4-N concentration was ranged from 0.01 mg/L to 1.30 mg/L.Soluble nitrogen was the main overland runoff pattern in sloping filed,the ratio of NO-3-N concentration was accounted for 21.02%~83.55% in soluble nitrogen,and NH＋4-N concentration was only about 1.02 %~38.58%.There were significant linear relationships between concentrations of different nitrogen patterns loss and fertilizer concentration,TN concentration and nitrogen output,fertilizer concentration and nitrogen output,their correlation coefficient were about 0.864 1~0.983 8.
出处
《水土保持学报》
CSCD
北大核心
2010年第4期7-11,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)
西南林业大学水土保持重点学科项目
关键词
地表径流
硝态氮
铵态氮
坡耕地
滇中
overland runoff
NO-3-N
NH＋4-N
sloping filed
the middle regions of Yunnan province
