前期土壤含水量对红壤坡面产流产沙特性的影响  

Effects of antecedent soil moisture on hillslope runoff-generation and soil erosion over red soil-mantled landscapes

作　　者：张向炎[1,2] 史学正[1,2] 于东升[1] 王洪杰[1] 刘振波[3] 张文太[1,2] 

机构地区：[1]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,江苏南京210008 [2]中国科学院研究生院,北京100039 [3]南京信息工程大学遥感学院,江苏南京210044

出　　处：《水科学进展》2010年第1期23-29,共7页Advances in Water Science

基　　金：国家重点基础研究发展计划(973)资助项目(2007CB407206);国家自然科学基金创新研究群体基金资助项目(40621001);中国科学院知识创新工程领域前沿资助项目(ISSASIP0715)~~

摘　　要：利用田间人工模拟降雨试验,研究了前期土壤含水量对两种红壤坡面降雨入渗、产流和产沙特性的影响。结果表明:前期含水量越高,两种土壤都是产流越快,达到稳定径流和入渗的时间越短。低含水量区(干态和稍干),两种土壤的径流系数和入渗率都与降雨时间呈线性关系,并在60 min内达不到稳定。高含水量区(稍湿和湿态),两种土壤的径流系数、入渗率及产沙速率与降雨时间关系都符合Boltzmann(玻耳兹曼)方程;第四纪红粘土发育的红壤稍干态和红砂岩发育的红壤干态下的产沙速率在整个降雨过程中变化不明显,并都维持在较低水平;第四纪红粘土发育的红壤干态和红砂岩发育的红壤稍干态下的产沙速率随着模拟降雨的进行而大致以线性关系增大。土壤前期含水量越高,两种土壤坡地累tk积入渗量都越小,雨水转化为土壤水分的比率亦越小。The effect of antecedent soil moisture on hillslpoe infiltration processes, runoff generations and soil erosions was investigated through artificial rainfall experiments at two sites with different types of red soil-mantled landscapes. The results show that the higher the level of antecedent soil moisture, the lower the accumulated infiltration is, the smaller the soil absorption is, the more quickly the runoff generation is, and the shorter the duration of runoff and infiltration steady is. The rainfall duration is found to be linearly correlated with both runoff coefficient and infiltration rate at the two sites under low initial soil moisture conditions. The state of equilibrium will not be reached within 60 minutes of the artificial rainfall. Under high initial soil moisture conditions, the Boltzmann equation can be used to describe the relationships between the rainfall duration and the runoff coefficient, the infiltration rate, as well as the soil erosion rate. Low or even invariable soil erosion rates are observed from the quaternary red clay under the slightly dry condition and from the red sandstone tinder the dry condition during the entire periods of artificial rainfalls. Interestingly, noted that the soil erosion rates at the two sites will increase linearly if the initial soil moisture conditions are swapped among the two eases.

关 键 词：前期土壤含水量 红壤 产流 产沙 

分 类 号：S152.7[农业科学—土壤学] TV121.7[农业科学—农业基础科学]