摘要
以野外布设的径流小区为研究对象,采用模拟降雨方法研究随机条件下降雨侵蚀过程中泥沙有机碳含量及流失过程的动态变化规律。结果表明:(1)降雨侵蚀过程中泥沙有机碳含量随降雨的进行逐渐降低并趋于平稳,与坡面土壤有机碳含量相比显著增高(p<0.01),有机碳在泥沙中明显富集,富集比最大值达1.780,泥沙中有机碳含量及富集比随侵蚀速率的增加明显减小且趋于稳定;(2)泥沙有机碳流失速率随降雨的进行先波动增大,达到最大值后又波动减小,最后逐渐趋于准稳定,整个过程呈单峰分布;(3)泥沙有机碳流失强度与土壤侵蚀强度呈显著性线性正相关(p<0.01),说明土壤侵蚀量决定侵蚀过程中有机碳流失量,准确获取土壤侵蚀强度是估算坡面有机碳流失量的基础。
In this study,simulated rainfall was conducted to mainly investigate and analyze organic carbon content of sediment and its dynamic change during the rainfall on the outdoor runoff plot under random conditions.The sediment organic carbon content,which was significantly higher than that of the soil organic carbon（p〈0.01）,decreased gradually during the early stage of the rainfall,then tended to be stable in the later stage.The organic carbon was obviously enriched in sediment,and the maximum of enrichment ratio was 1.780.The content and enrichment ratio of organic carbon in sediment decreased obviously with the increasing of erosion rate,and tended to be stable.The loss process of sediment organic carbon showed a unimodal distribution during the rainfall,which increased first with the rainfall,then decreased after reaching the maximum value,and finally tended to quasi stable.There was a significant linear relationship between soil organic carbon loss and soil erosion amount（p〈0.01）,indicating that soil erosion amount determined the organic carbon loss during the erosion process,so accurate estimation of soil erosion intensity was the basis of estimating organic carbon loss on the slope.
作者
任瑞雪
张风宝
杨明义
王永吉
王子豪
邓鑫欣
REN Ruixue;ZHANG Fengbao;YANG Mingyi;WANG Yongji;WANG Zihao;DENG Xinxin(State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A ＆ F University, Yangling , Shaanxi 712100;Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100)
出处
《水土保持学报》
CSCD
北大核心
2017年第6期15-19,共5页
Journal of Soil and Water Conservation
基金
国家重点研发计划项目(2016YFC0402406)
国家自然科学基金项目(41571130082
41371283
41671281)
关键词
坡面侵蚀
模拟降雨
土壤有机碳流失
slope erosion
simulated rainfall
soil organic carbon loss
