考虑生物结皮影响的陆气湍流模式研究

A Turbulent Model of the Land-Atmosphere Interaction with the Crust Layer Influence

在以前工作基础上 ,针对腾格里沙漠人工植被区陆气水热传输过程 ,提出了一个多层陆气耦合模式。特别给出了导水率的计算模型和修正后的根系吸水模式 ,考虑了结皮层对土壤水分入渗的影响以及植被演化的过程。陆面过程耦合模式分别对大气、植被、土壤作多层划分 ,以助于细致了解沿高度分布的各物理量。同时 ,利用本模式对中国科学院沙坡头沙漠站人工植被区陆气水热交换过程进行了数值模拟 ,模拟结果与实测值吻合较好 。

In the paper, we have elucidated the importance of investigation on land surface\|atmosphere interaction for mankinds living environment protection and local economics development as well as its present state. Based on the previous work, a coupling micrometeorological model for SPAC system over wheat field in the Tengger Desert is presented. Especially, the leaf stoma non\|saturation condition is considered to calculate the evapotranspiration, and the root absorption model is revised as well. The presence of microbiotic crust changes the soil hydraulic conductivity, alters the temporal and spatial distribution of limited precipitation in sand layer and leads to the degradation of deep\|rooted shrubs. The canopy is divided into several layers, aiming at revealing the vertical profiles of mean quantities within it and providing scientific basis for parameterization of terrestrial processes. The model is shown capable of well simulating the microenvironment of wheat canopy in good agreement with measured mean temperature, specific humidity and latent heat fluxes \%et al\%. And the sensitivity test is carried out as well to analyze canopys influence.