摘要
研究川中丘陵区次降雨过程中不同土地利用方式对土壤侵蚀及养分流失的影响。结果表明:(1)不同土地利用方式下,地表径流量的变化均随着降雨时间的增加呈对数变化趋势,在同一降雨时间内,地表径流量均表现为农田>果园>草地>灌丛>林地。(2)农田泥沙流失量随降雨时间的增加幅度较大,且在降雨后期出现陡增陡降的变化特征,其他土地利用方式下泥沙流失量的增加幅度较小;不同土地利用下泥沙流失量大小顺序为:农田>果园>草地>灌丛>林地。(3)农田和果园地表径流量和壤中流总量显著高于灌丛和林地(p<0.05),地表径流量和壤中流均表现为:农田>果园>草地>灌丛>林地。(4)不同土地利用方式下泥沙积累量均随降雨时间的延续而呈指数变化趋势。(5)不同土地利用方式下水相氮磷流失量、泥沙氮磷流失量和氮磷流失总量均表现为:农田>果园>草地>灌丛>林地;不同土地利用方式下降雨径流过程中,氮素的流失是以径流水相为主,而磷的流失是以侵蚀泥沙相为主。(6)不同土地利用方式降雨前期土壤全氮和全磷含量大小均表现为农田>果园>草地>灌丛>林地,泥沙氮磷含量比雨前土壤表层氮磷含量有所增加,说明侵蚀泥沙对氮、磷具有富集作用,并且不同土地利用方式下侵蚀泥沙富集磷素能力高于富集氮素能力,综合比较可知,农田和果园侵蚀泥沙富集养分的能力最高,而灌丛和林地是减少水土流失的土地利用方式。
Characteristics of soil nutrient losses under different land use types in purple soil during course of rainfall were studied.The results indicated that：（1）the surface runoff under different land use types had a logarithmic change tendency with the duration of rainfall,which followed the order：farmland〉orchard〉grassland〉shrub land〉woodland;（2）the increasing range of soil erosion of grassland was larger,and farmland,woodland,orchard was lower,which decreased in the order：farmland〉orchard〉grassland〉shrubland〉woodland;（3）the surface runoff and interflow of orchard and farmland were significant higher than those in the woodland and shrub land（p〈0.05）,which decreased in the order：farmland〉orchard〉grassland〉shrubland〉woodland;（4）the sediment accumulation under different land use types had a exponential function change tendency with the increase of rainfall;（5）the nitrogen and phosphorus losses along with runoff,nitrogen and phosphorus losses along with sediment and the total losses of nitrogen and phosphorus decreased in the order：farmland〉orchard〉grassland〉shrubland〉woodland;（6）the total contents of nitrogen and phosphorus under different land use types decreased in the order：farmland〉orchard〉grassland〉shrubland〉woodland before rainfall;contents of nitrogen and phosphorus in the sediment was higher,indicating that erosion and sediment had the enrichment effect of nitrogen and phosphorus,and the nitrogen enrichment was higher than phosphorus enrichment,the nutrient enrichment is the highest in the grassland.
作者
张晓艳
李琴书
ZHANG Xiaoyan;LI Qinshu(Yunnan College of Business Managent,Kunming 650106,China;Faculty of Environmental Sciences and Engineering,Kunming University of Science and Technology,Kunming 650093,China)
出处
《水土保持研究》
CSCD
北大核心
2018年第5期12-17,共6页
Research of Soil and Water Conservation
