Disentangling leaf area and environmental effects on the response of the net ecosystem CO2 exchange to diffuse radiation
Disentangling leaf area and environmental effects on the response of the net ecosystem CO2 exchange to diffuse radiation
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DOI：
10.1029/2008gl035090
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发表时间：
2008-08
影响因子：
5.2
通讯作者：
G. Wohlfahrt;A. Hammerle;Alois Haslwanter;M. Bahn;U. Tappeiner;A. Cernusca
中科院分区：
文献类型：
--
作者：
G. Wohlfahrt;A. Hammerle;Alois Haslwanter;M. Bahn;U. Tappeiner;A. Cernusca
关于为什么某些生态系统的净生态系统二氧化碳交换 (NEE) 对漫射辐射的敏感度低于其他生态系统，以及其他环境因素在确定 NEE 对漫射辐射的响应中所起的作用，目前正在进行讨论。使用来自奥地利温带山地草原的六年数据集，我们表明生态系统之间的差异可以根据其绿地面积指数（GAI；每平方米地面面积的平方米绿色植物面积）来协调——对漫射辐射的敏感性随着 GAI 的增加而增加。我们的数据表明，当 GAI 低于 2 m2 m−2 时，漫射辐射对 NEE 的影响可以忽略不计。研究发现，空气/土壤温度和空气湿度的变化与漫射辐射的比例同时发生，会放大所调查的温带山地草原生态系统对漫射辐射的敏感性。
There is an ongoing discussion about why the net ecosystem CO2 exchange (NEE) of some ecosystems is less sensitive to diffuse radiation than others and about the role other environmental factors play in determining the response of NEE to diffuse radiation. Using a six‐year data set from a temperate mountain grassland in Austria we show that differences between ecosystems may be reconciled based on their green area index (GAI; square meter green plant area per square meter ground area) ‐ the sensitivity to diffuse radiation increasing with GAI. Our data suggest diffuse radiation to have a negligible influence on NEE below a GAI of 2 m2 m−2. Changes in air/soil temperature and air humidity concurrent with the fraction of diffuse radiation were found to amplify the sensitivity of the investigated temperate mountain grassland ecosystem to diffuse radiation.