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摘要
Soil thermal conductivity (lambda) models are needed frequently in studying coupled heat and water transfer in soils. Several models are available, but some are complicated and some produce relatively large errors. In this study, we developed a simple model for estimating lambda from soil texture, bulk density (rho(b)), and water content (theta). Three parameters, alpha, beta, and lambda(dry), are included in the model, where lambda(dry) is determined by rho(b) and alpha and beta are shape factors estimated from soil texture and rho(b). Empirical relations were developed for alpha and beta by fitting the model to heat-pulse (HP) measurements of lambda(theta) on seven soils of various textures. The model performance was evaluated with independent lambda(theta) data from independent HP measurements and literature values. The results show that the model is able to express the lambda(theta) curves from oven dry to saturation at fixed rho(b) values. When rho(b) is varied, the estimated lambda data agree well with measured values. The root mean square errors are <0.15 W m(-1) K-1, and the bias is within 0.10 W m(-1) K-1. The new model has the potential for use in studying heat movement in soils of varying texture, bulk density, and water content and can be incorporated into numerical algorithms for describing coupled heat and mass transfer processes.
- 出版日期2014-12
- 单位中国农业大学; 中国林业科学研究院林业研究所
