Atmosphere-Biosphere Exchange in a Forest Ecosystem in New England

Wofsy博士和Bazzaz博士将确定新英格兰地区大气和森林生态系统之间重要气体的净交换率。其目的是量化在马萨诸塞州彼得沙姆市哈佛森林的混合阔叶林中二氧化碳、水、臭氧、NO、NO2、NOY(所有氧化氮的总和)和总碳氢化合物的大气-生物圈交换速率。这些测量将有助于阐明该系统及其主要组成部分对自然环境变化和污染物输入的反应，为了解生态系统对气候变化和全球污染的反应提供必要的数据。整个生态系统的气体交换速率将使用涡旋相关方法进行测量，为期2个或更多个年度周期。将监测土壤排放速率，并在整个林冠范围内测量完整树叶的交换率。大气中的浓度将在从地面到30米的8个水平上进行连续监测。将为生态系统开发生物活性气体交换的诊断模型，以帮助阐明调节气体交换的因素。这项研究将确定森林中二氧化碳和其他气体在所有季节的净生态系统交换(NEE)，将确定土壤和整个树冠上的叶片对净生态系统交换(NEE)的贡献，并将研究臭氧、氮氧化物以及太阳辐射、温度、湿度变化对CO2固定和其他交换过程的可能影响。将确定气态碳氢化合物在森林碳收支中的作用。Wofsy博士和Bazzaz博士是各自领域的领导者，对这项研究的机构支持是杰出的。

Drs. Wofsy and Bazzaz will determine net exchange rates for important gases between the atmosphere and a forest ecosystem in New England. The purpose is to quantify atmosphere-biosphere exchange rates for CO2, H2O, O3, NO, NO2, NOy (sum of all oxidized nitrogen), and total hydrocarbons in a mixed hardwood stand in Harvard Forest, Petersham, Massachusetts. The measurements will help to elucidate the response of the system, and its main component parts, to natural environmental variations and pollutant inputs, providing data essential for understanding ecosystem response to climate change and global pollution. Rates of gas exchange for the whole ecosystem will be measured using eddy-correlation methods, for 2 or more annual cycles. Soil emission rates will be monitored, and exchange rates for intact leaves will be measured throughout the forest canopy. Concentrations in the atmosphere will be monitored continuously at 8 levels from the ground to 30m. A diagnostic model for exchange of biologically active gases will be developed for the ecosystem, to aid in elucidating the factors regulating gas exchange. The study will determine net ecosystem exchange (NEE) of CO2 and other gases in the forest in all seasons, will define contributions to NEE of soils and of leaves throughout the canopy, and will examine possible influence of O3, nitrogen oxides and variations in solar irradiance, temperature, humidity, on CO2 fixation and other exchange processes. The role of gaseous hydrocarbons in the forest carbon budget will be defined. Dr. Wofsy and Bazzaz are leaders in their fields, and the institutional support for this research is outstanding.