摘要
土壤水分持留曲线指的是土壤体积水分含量与压力水头之间的关系,在研究土壤水分流动和溶质运移中有着非常重要的作用。由于它们之间的关系复杂,难以从理论上推导出确切的关系式;但通过大量的试验研究,人们已提出了许多经验公式来描述它,其中比较常用的有:Brooks-Corey（1964）模型,Gardner（1970）模型,van Genuchten（1980）模型和 Gardner-Russo（1988）模型等。在这些模型中都含有许多待求的参数。本文借助于最小二乘法,形成了确定这四个模型中的参数所对应的非线性方程组,并用Picard迭代求解它们。最后,用数值例子说明了这四种模型对不同类型土壤的适应性。
Soil water retention curve refers to the relationship between volumetric water content and pressure head, which plays a very important role in solving the problems of water flow and solute transport in soil. Due to its complexity, it is difficult to derive an accurate equation theory erically However, quite a number of experience formulas have ever been proposed on the basis of a number of experiments, such as Brooks-corey(1964) model, Gardner(1970) model, van Grnuchten(1980) model, and Gardner-Russo(1988) model etc. , in which many parameters need to be determined. In this paper, by means of the least square method, the nonlinear equation groups that are used to obtain the parameters in models above mentioned, are derived respectively, and their Picard iterative forms are got. At last, the suitability of the four models for different types of soil is indicated by the numerical examples.
出处
《土壤学报》
CAS
CSCD
北大核心
2002年第4期498-504,共7页
Acta Pedologica Sinica
基金
国家自然科学基金(No.49971041)
973项目(G1999011803)
所长基金(ISSDF0004)
ACIAR(LWR1/96/164)资助
