摘要
预报非饱和土壤水分运动必须首先获得土壤水分运动参数。土壤水分运动参数包括土壤水分特征曲线和导水率。本文使用积分方法求解了一维水平非饱和土壤水分运动问题，根据其解建立了推求非饱和土壤水分运动参数的简单入渗法，用以推求ｖａｎ Ｇｅｎｕｃｈｔｅｎ特征曲线模型中的参数α和ｎ。α和ｎ是根据湿润区的特征长度、吸渗率和土壤的饱和导水率（ｋｓ）来确定的，而非饱和导水率可由α、ｎ和Ｋｓ确定。这一新的简单入渗法是基于Ｒｉｃｈａｒｄｓ方程和土壤导水特征的闭合型方程。简单入渗法提供了利用瞬态水流方法来确定土壤水分特征曲线而替代通常的平衡法。简单入渗法是一个全新的、简捷的确定土壤导水特性的方法。
Summary Information of soil hydraulic propenties is required to predict water flow in unsaturated soils. Soil hydraulic propeeres include .soil water characteristic curve and hydraulic conductivity. In this paper an integral method is used to solve the Problem of wader absorption into an one-dimensional and horizontal soil column. According to the solved results, a simple infiltration is established to estimate the parameters, a and n, in the van Genuchten model of a soil water characteristic curve. The two parameters, a and n, in the characteristic curve model are estimated by the characteristic length of wetted zone, sorptivity, and saturated hydraulic conductivity. Unsaturated soil hydraulic conductivity is then estimated from the parameters determined in the soil water characteristic curve. ms new method uses both Richards' equation and the closed form equations of soil hydraulic properties. The simple infiltration method provides a transient warier flow approach to estimate the soil water characteristic curve instead of the usual equilibrium method. This is a new and simple means to determine soil hydraulic properties.
出处
《土壤学报》
CAS
CSCD
北大核心
2000年第1期1-8,共8页
Acta Pedologica Sinica
基金
中国科学院重大项目!(KZ951-B1-211)
国家自然科学基金
关键词
简单入渗法
土壤水分
运动参数
水分运动
A simple infiltration method
Soil hydraulic properties
Soil water
