【摘要】 以黄土丘陵沟壑区燕沟流域为研究对象,对流域内2006年不同类型土壤水分垂直变化进行了分析。结果表明,在实验设计条件下,不同层次的土壤水分变幅较大,坝地、梯田和坡地各层土壤含水量变化与降雨量的季节性变化呈现出较一致的趋势,而苹果地除0—100 cm外,100—200 cm随着降雨量的季节性变化出现较大波动;不同类型土地的土壤含水量变化程度不同,同一类型土地的土壤含水量变化幅度也有差异,10 cm处土壤含水量变异系数最大,随着土层深度的增加变异系数逐渐递减。根据土壤含水量变异系数分析,将不同类型土壤含水量垂直变化划分为速变层、活跃层、次活跃层和相对稳定层4个层次;并建立了不同类型土地各层土壤含水量变异系数回归方程。更多还原

【Abstract】 The vertical variations of different types of soil moisture in Yan’gou watershed in the hilly and gully area of the Loess Plateau are analyzed.Results show that the variation of soil moisture content in different layers is great under the condition of designed experiment.Soil moisture contents on dam,terrace,and slope are consistent with the seasonal change of rainfall.Soil moisture content of 100—200 cm layer in orchard fluctuates significantly with the seasonal change of rainfall.The variation of soil moisture content is different in extent not only under the different land types,but also under the same land type.The variation coefficient of soil moisture content is the biggest at 10 cm depth and is gradually reduced with increased soil depth.According to the analysis of the variation coefficient,the vertical distribution of soil moisture content under different land types may be divided into vertiginous layer,active layer,subactive layer,and relatively stable layer.Regression equations of the variation coefficient are also found for the soil layers of different land types.更多还原