容重变化与土壤水分特征的依赖关系研究  

Dependent Relationship Between Bulk Density Changes and Soil Water Characteristics

作　　者：吕殿青[1,2] 邵明安[2] 潘云[1] 

机构地区：[1]湖南师范大学资源与环境科学学院,湖南长沙410081 [2]中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100

出　　处：《水土保持学报》2009年第3期209-212,216,共5页Journal of Soil and Water Conservation

基　　金：国家自然科学基金资助项目(40801083);湖南省重点学科资助项目;中国博士后基金(20060391018);黄土高原土壤侵蚀与旱地农业国家重点实验室基金(10501-200)

摘　　要：通过石蜡固定容积方法,用离心机测定黄土高原典型两种扰动土壤不同压实容重下的水分特征曲线,采用Brooks-Corey模型对实验数据进行拟合,分析容重对模型参数和土壤持水性能的依赖关系。结果表明:随着土壤容重的增大,同一吸力下的有效饱和度增大,土壤水分特征曲线坡度越平缓。Brooks-Corey模型参数λ随容重的增大而减小,参数α随容重的增大而减小,且容重与参数α,λ可用幂函数和线性关系来描述。随着压实程度的增加,土壤的最大有效水含量却明显减少。因此,土壤压实使得其对水分的调节能力下降,降低土壤的水分存储能力,不利于植物生长。Soil water characteristic curves were measured under a series of certain bulk density for three soils with centrifuge. Bulk density was kept constant by fixing soil volume using paraffin. The experiment data were fitted with Brooks-Corey model and dependent relationship of bulk density on model parameters and soil retention capacity were also analyzed. The results showed that valid saturation increased in same suction and slope of soil water characteristics curve became smoother with the increase of bulk density. Brooks-Corey model parameter 2, decreased with the increase of bulk density for studied soils,and their relations could described well by linear function. Parameter a decreased and the relationships between a and bulk density could be expressed by power function. Soil potentially available moisture content decreased obviously with increase of compaction. So soil compaction weakens the capacity of soils in regulating water supply and isn＇t helpful of plants growth.

关 键 词：容重 Brooks-Corey模型 有效含水量 

分 类 号：S152.7[农业科学—土壤学] S152.5[农业科学—农业基础科学]