Net ecosystem exchange of CO2 and H2O in a subtropical mountain cloud forest (Taiwan)

本研究旨在利用涡动相关法，量化台湾亚热带山地云雾林生态系统中CO2和H2O的净交换量，并进一步了解复杂地形下CO2和H2O的进出口通量。在台湾北部海拔1650 m的亚热带山地云雾林中，提出了一项靠近元阳湖（YYL）遗址的生态系统实验研究。摘要本研究的目的是探讨台湾樟树林内二氧化碳收支及可能平流对净生态系统-大气交换的影响。台湾Chamaecyparis obtusa ar. formosana是一种特殊的柏树，仅生长在台湾的山云地区，近年来通过林业活动得到了更新。在全球变化的内容中，量化二氧化碳的生物圈-大气交换是非常重要的，特别是在研究不充分的地区。在非均匀地形上改进测量方法也很重要，这样就可以量化不同森林冠层上的气体交换。虽然文献中有关于平流通量的广泛讨论，但对平流通量和水平通量散度对东北东线测量的直接观测很少。该问题应采用涡动相关法进行二维测量。

The aim of the project is to quantify the net ecosystem exchange of CO2 and H2O in a subtropical mountain cloud forest in Taiwan by using the eddy covariance method, and to achieve more information about the import and export fluxes of CO2 and H2O over complex terrain.An experimental ecosystem research study close to the Yuan Yang Lake (YYL) site, in the subtropical mountain cloud forest of northern Taiwan at 1650 m a.s.l., is proposed. The aim of the study is to examine the CO2 budget and possible advection on estimates of net ecosystem-atmosphere exchange within a stand of Chamaecyparis obtusa var. formosana in Taiwan. Chamaecyparis obtusa var. formosana is an extraordinarily cypress species which only grows in the mountain cloud regions in Taiwan and which has been regenerated through forestry activities lately. In the content of global change, it is very important to quantify the CO2 biosphere-atmosphere exchange especially of the not well examined regions. It is also important to advance measurement methods on heterogeneous terrain so that it will become feasible to quantify gas exchange over various forest canopies. Although extensive discussion of the advective fluxes exists in literature, direct observations of the contributions of advection and horizontal flux divergence to NEE measurements are rare. The problem should be solved with two dimensional measurements by using the eddy covariance method.