摘要
通过对川中丘陵区不同施肥坡地径流、泥沙和养分流失的观测与测定分析,研究了紫色土坡耕地暴雨下的产流产沙特征和氮、磷养分流失特征。结果表明,秸秆还田显著影响雨季紫色土坡耕地土壤侵蚀和产流情况;相比单施化肥处理。秸秆还田的泥沙量减少了70%~82%.地表径流量减少了26%~31%,渗漏径流量增加了30%~52%。秸秆还田显著减少了N、P的流失.减幅为60%~76%;各处理P流失的强度顺序依次为:NPK〉RSD〉RSDNPK〉RSDNP〉RSDN,N流失的强度顺序为:NPK〉RSDN〉RSDNPK〉RSDNP〉RSD;地表径流损失是P的主要流失途径。颗粒态是地表径流中P的主要迁移形态.磷酸盐是地表径流中溶解态总磷的主要组成部分,渗漏径流中的PO4^3- -P/DTP显著下降。渗漏淋失是N的主要流失途径.硝态氮是渗漏液中N的主要迁移形态.地表径流中NO3^- -N/DTN较渗漏液略低,溶解态总氮在地表径流N流失中所占比例超过50%。
A field experiment was conducted to study the characteristics of nutrient loss in hilly area of central Sichuan basin. There were 5 kinds of fertilization systems: application of N+P+K (NPK), straw returned to field alone (RSD), straw + N (RSDN), straw +N+P (RSDNP), straw +N+P+K (RSDNPK). Series water samples were collected from the different plots in each rainfall event. The results showed as follows: Returned straw significantly affected the soil erosion and runoff from slope cropland of purple soil. Compared with NPK, the sediment yield from the application with returned straw decreased by 70%- 82%, the surface runoff decreased by 26%-31%, and the leaching amount increased by 30%-52%. Returned straw significantly reduced 60%-76% of the total nutrient loss. There were significant differences in the losses of nutrient of various treatment plots. The order of phosphorus loss was NPK 〉RSD〉 RSDNPK〉RSDNP 〉 RSDN, and the order of nitrogen loss was NPK 〉 RSDN 〉 RSDNPK〉RSDNP〉 RSD. As to phosphorus, transported by surface runoff was the major way, and total particulate phosphorus was the major form in that way. PO4^3- -P is major form of dissolved total phosphorus in surface runoff. On the other hand, PO4^3- -P / DTP in leachate significantly decreased. As to nitrogen, transported by leaching was the major way, NO3^- -N was the major form in leachate and there was not a same situation in surface runoff.
出处
《水土保持学报》
CSCD
北大核心
2006年第1期30-32,36,共4页
Journal of Soil and Water Conservation
基金
国家自然科学基金(40571093)
国家基础研究发展计划(2003CB415202)资助
关键词
秸秆还田
养分流失
地表径流
渗漏
紫色土坡耕地
returned straw
nutrient loss
surface runoff
leaching
slope cropland of purple soil