摘要
采取模拟试验的方法,研究了在人工降雨和自然降雨条件下,坡度、土壤质地、地表覆盖状况以及施肥方式对坡地农田径流中氮素污染负荷的影响.结果表明:随着坡度的增加,农田土壤径流中氮的浓度和氮的输出量都增加;在人工模拟降雨和自然降雨条件下,土壤径流中氮的浓度变化趋势相同,都随着质地的变粗而减少;和裸地相比,种植小麦能明显减少土壤径流中氮的浓度和输出量,氮的流失量减少范围在11.80～238.46kg/hm2之间;相同施肥量条件下,面施氮肥时土壤径流中氮的浓度和输出量比穴施时明显增加.
Simulated experiment was used in this experiment to study the effects of soil factors on the farmland nitrogen losses and its concentration under artificial rainfall and natural rainfall. A number of soil and landscape factors were taken into account such as slope gradient, plant covers, fertilizers' application performances as well as rainfall intensity. The result showed: the concentration of total nitrogen (TN) and the loss rate increased when the slope gradient became high; there has no significant difference in TN concentration between under artificial rainfall and under natural rainfall, TN concentration in runoff is smaller with the courser soil texture; and obviously lower with wheat planting than without covering, among which the loss decreased 11.80~238.46kg/hm2; in condition of the same N application account, diffuse application of fertilizer caused more nitrogen loss than cave application.
出处
《中国农学通报》
CSCD
2004年第5期148-150,共3页
Chinese Agricultural Science Bulletin
基金
云南省应用基础研究项目(1999C0011G)。
