红壤坡地干旱季节地表-大气界面水分传输——以茶园为例  

Water transport through interface between land and atmosphere in dry season on red soil slopes

作　　者：段华平[1] 卞新民[1] 谢小立[2] 王凯荣[2] 

机构地区：[1]南京农业大学农学系,南京210095 [2]中国科学院亚热带区域农业研究所,长沙410125

出　　处：《生态学报》2004年第3期457-463,共7页Acta Ecologica Sinica

基　　金：中国科学院知识创新资助项目(KZCX2 - 40 7)~~

摘　　要：以红壤坡地茶园为研究对象 ,用波纹比——能量平衡法研究了红壤坡地干旱季节地表 -大气界面水热传输特性 ,结果表明 :在茶园稳定生态系统中 ,气象因素和表层土壤含水量是影响地表 -大气界面水热传输的重要因素。特别是在受旱条件下 ,土壤水分对地表 -大气界面水热传输起决定作用 ,土壤水分越小 ,潜热通量越小 ,显热通量越大 ,反之亦然。观测期间 ,棵间蒸发量占总蒸散量的 3 2 % 。Water resource is very rich in red soil regions of China. But the dramatic changes and spatial unbalances of rainfall in these regions is unfavorable for the agricultural sustainable development of this region. Based on Taoyuan Agro-ecological Experimental Station, Chinese Academy of Sciences, water transport processes through soil-atmosphere and leaf- atmosphere interface and their relationships with the environmental conditions were studied on red soil slopes tea plant. The aim of this study was to investigate the response characteristics of plant to seasonal drought and the approaches for regulating the interface processes and to provide the theoretical and practice basis for avoiding from or fighting against drought during the agricultural exploitation of red soil slopes. The results are as follows: (1)When the effect of crop was neglected, seasonal variation of water transfer flux of soil-atmosphere interface was affected significantly by microclimate and top layer (0~20cm) soil water contents. Correlation analysis showed that the correlation coefficients between soil evaporation under crop canopy and air temperature, leaf temperature, relative humidity were highly significant (0.63^(**), 0.76^(**),-0.61^(**), n=19); the correlation coefficients between soil evaporation under crop canopy and net radiation, soil surface temperature, sunlight hour were significant (0.48~*, 0.50~*, 0.51~*, n=19). When the LAI was 2.2 on red soil slopes, the function of relative evaporation (E/ET_0) to soil water content(θ) was as follow: E/ET_0=1.1807+0.3876Lnθ,R^2=0.6009,P<0.01. (2)Stomatal behavior had the mechanisms of respond to environment change. The daily variation curve of stomatal resistance was W form under drought condition, and the daily variation curve of stomatal resistance was U form under wet condition, and stomatal resistance under drought condition was more than that of under wet condition. Multi-regression analysis between stomatal conductivity and light intensity, air temperature, relative humidity showe

关 键 词：红壤坡地 干旱季节 地表/大气界面 水分传输 农田 水分利用效率 土壤 水分蒸发 生态系统 

分 类 号：S152.7[农业科学—土壤学] S155.25[农业科学—农业基础科学]