Understanding of heat and water balance, and evapotranspiration characteristics on Asian monsoon area with one-dimensional land surface models

以东西伯利亚雅库茨克针叶林为研究对象，建立了包括两层植被的一维地表模型（2LM）。模拟了落叶松林与草地的潜热通量较小（感热通量较大），与观测值相符。尽管落叶松与禾草的叶片生理特性没有差异，但其叶片面积对蒸腾的贡献较小。将Jarvis气孔导度模型引入2LM。通过植物生理学家在东北亚几个地点的测量，确定了两个参数集。一个是通过在每个场址进行实地测量获得的；另一种是由汇集所有数据确定的，并对所有站点通用。利用这两个参数集模拟了相似的季节水通量和能量通量。泰国北部的蒸腾高峰出现在旱季后期。这意味着利用了雨季积累的深层土壤水分。采用多层模型对不同生根深度下的蒸腾峰值和年径流量进行了模拟，并对生根深度为4 ~ 5 m时的蒸腾峰值和年径流量进行了模拟。为了模拟土壤中的热、水环境和土壤呼吸，在模型中引入了二氧化碳和水溶液的扩散过程。该模型适用于泰国北部常绿森林；合理模拟了土壤温度、含水量、二氧化碳浓度和土壤呼吸的观测剖面。

A one-dimensional land surface model (2LM) including two vegetation layers was adapted to taiga larch forest in Yakutsk eastern Siberia. Small latent heat (large sensible heat) flux was simulated in the larch forest compared with a grass land, it corresponds to observation. It is explained by small leaf area contributing transpiration even if there are no differences on leaf physiological characteristics between larch and grass.Jarvis stomatal conductance model was introduced into 2LM. Two parameter sets was determined with measurements by plant physiologists in several sites in north-east Asia. One is obtained by in situ measurements in each site ; the other is determined by pooled all data, and common to all sites. Similar seasonal courses of water and energy fluxes were simulated using these two parameter sets.Transpiration peak is observed in late dry season in northern Thailand. It means that deep soil water accumulated in rainy season was used. According to examinations with various rooting depth using a multi-layer model, the transpiration peak and annual runoff were simulated with 4 to 5 meters of rooting depth.In order to simulate heat and water environment in soil and soil respiration, diffusion processes of carbon dioxide and water solutions were introduced into the model. The model was adapted to evergreen forest in northern Thailand ; observed profile of soil temperature, water content and carbon dioxide concentration, and soil respiration were reasonably simulated.