中国水土保持科学2018，Vol.16Issue(1)：38-45,8.DOI:10.16843/j.sswc.2018.01.005
不同降雨等级下耕作措施对坡地产流产沙的影响
Effects of tillage measures on runoff and sediment yield of farmland under different rainfall levels
摘要
Abstract
[Background] As an agricultural measure,tillage practices play an important role in soil and water conservation.To provide the basis for effective prevention and control of soil erosion in different rainfall levels,soil erosion characteristics of sandy soil was explored under cross-ridge and straight-ridge cultivation in the hilly area of western Sichuan.[Methods] Based on the measured data of 1984-1987 in 4 runoff plots (20 m × 5 m of each) in Chaoyang reservoir,Pujiang County,western Sichuan,runoff,rainfall duration,and sediment yields between cross-ridge plots and straight-ridge plots,and between slope 10° plot and slope 20° plot were analyzed using SPSS 20.0 and compared.Rainfall was measured using siphon rain gauge.The generated rainfall runoff,the depth of runoff and runoff coefficient were calculated when each rainfall process finished and the water level in each plot was recorded.[Results] Heavy rain and rainstorm were erosive rainfall patterns which mainly occurred in July and August in western Sichuan.It was difficult for light rain and moderate rain to cause soil erosion.Runoff coefficient of every runoff plot gradually increased along with rainfall levels.The runoff coefficient of straight-ridge cultivation plot was 1.33 to 3.81 times that of the cross-ridge of cultivation plot,which reached the biggest value during the period of rainstorm.Under the same cultivation measures,the runoff coefficient of 10°and 20°slope was equal.The soil concentration increased with the rainfall level first and then decreased,and the soil concentration was the largest during the period of heavy rain,and the effect of the slope was more obvious.With the increase of rainfall level,the dispersion degree of runoff in every plot was decreasing.It showed that the effect of large rainstorm and extraordinary rainstorm on soil's initial water content was not obvious.The sediment yield was irregular,for example,the sediment yield of extraordinary rainstorm was less than that of large rainstorm.By establishing the regression equation between runoff and sediment yield and rainfall duration,we may see that the simulation effect of runoff depth was better than that of sediment yield.[Conclusions] Overall,runoff volume did not increase with the increase of rainfall level in the farmland of hilly region of western Sichuan.Under extraordinary rainstorm,sediment yield of the cross-ridge area was higher than that of the straight-ridge area.Meanwhile,the sediment yield of extraordinary rainstorm was less than that of the large rainstorm.It indicated that the mechanism of sediment yield was relatively complex under different rainfall levels.关键词
耕作措施/降雨等级/径流系数/土壤侵蚀/川西丘陵区Key words
tillage practices/rainfall level/runoff coefficient/soil erosion/hilly region of western Sichuan分类
农业科技引用本文复制引用
郑江坤,杨帆,王文武,郎登潇,马星,廖峰,陈旭立..不同降雨等级下耕作措施对坡地产流产沙的影响[J].中国水土保持科学,2018,16(1):38-45,8.基金项目
中国博士后科学基金面上项目“四川紫色土土壤有机碳流失机理及对碳储量的影响”(2012M511938) （2012M511938）
国家自然科学基金项目“华北土石山区典型林分坡地径流形成机制研究”(41601028) （41601028）
水利部公益性行业科研专项“水土保持生态效应监测与评价技术研究”(201501045) （201501045）
