Dynamic analysis of the evaporation from forest floor taking consideration in the canopy structure

考虑冠层结构的森林地面蒸发动态分析

基本信息

批准号：
18580143
负责人：
HATTORI Shigeaki
金额：
$ 2.39万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18580143/
关键词：
evaporation from forest floor canopy structure micrometeorological factor water balances heat balance litter layer deciduous broad-leaved forest 自動開閉式チャンバー

项目摘要

The evaporation from forest floor has been observed for two years in a deciduous broad-leaved forest in Seto city, taking the thickness, of litter layer into consideration. The characteristics of the daily and seasonal changes of the evaporation from forest floor was analyzed considering the influences of micrometeorological factors, soil moisture of litter layer and canopy structure. As the results, the following findings were obtained.1.The characteristics of daily and seasonal changes of evaporation from forest floor The daily evaporation was 0.42 mm in foliated season (May-October) and 0.29 mm in defoliated season (November-April) . These data were almost the same range of evaporation reported so far in various forests. The ratio of evaporation from forest floor in forest evapotranspiration from dry canopy was about 14% in foliated season and about 29% in defoliated season.2.The response of evaporation from forest floor to micrometeorological condition The regression analysis was carried out to make clear the influence of micrometeorological factors on the evaporation from forest floor. We confirmed that the saturation vapor deficit correlated closer with the evaporation from forest floor than the other factors.3.The influences of the litter layer on the evaporation from forest floorThe evaporation from forest floor with litter layer decreased comparing with the evaporation from bare soil surface ; litter layers with 1.5 cm thickness and 4 cm thickness decreased by about 5 % and by about 19% respectively. The limitation of evaporation from forest floor might be larger according to the thickness of litter layer.

考虑到枯落物层的厚度，在濑户市的落叶阔叶林中，对森林地面的蒸发进行了两年的观察。综合考虑微气象因素、枯落物层土壤湿度和冠层结构的影响，分析了森林地表蒸发量的日变化和季节变化特征。结果表明:1、林地蒸发量日变化和季节变化特征叶叶季(5-10月)日蒸发量为0.42 mm,落叶季(11-4月)日蒸发量为0.29 mm。这些数据与迄今为止报告的各种森林的蒸发范围几乎相同。森林地表蒸发量占森林干冠蒸散量的比例，叶季约为14%，落叶季约为29%。2、林地蒸发量对微气象条件的响应通过回归分析，明确了森林地表蒸发量对微气象条件的响应。微气象因素对森林地面蒸发的影响我们证实，与其他因素相比，饱和水汽亏缺与森林地表蒸发量的相关性更密切。3.凋落物层对森林地表蒸发量的影响有凋落物层的森林地表蒸发量比裸土表面蒸发量减少。 ; 1.5厘米厚和4厘米厚的枯落物层分别减少约5%和约19%。根据凋落物层的厚度，森林地面蒸发的限制可能会更大。