以位于江苏句容下蜀的长江三角洲森林生态站栎林为研究对象,采用涡度相关技术进行长期CO2通量观测,得到2007年12月至2008年11月间栎林净碳交换(NEE)的日变化过程:栎林从7:00左右开始吸收CO2,10:00至14:00期间,对CO2的吸收一直维持在较大量,到17:30左右转化为碳排放。对于栎林NEE与光合有效辐射(PAR)及气温的响应关系分析表明:当光合有效辐射大于5μmol/(m2.s)时,在不同季节NEE与PAR相关关系不同,NEE的月平均值与冠层月平均温度呈直线相关。
The research choice the secondary oak forest ecosystem in the forest eco-positioning location research station of Yangtze River Delta,Southeastern China,and monitored the CO2,H2O,temperature,moisture,PAR,and so on by eddy covariance.The data of regulated change and process of diurnal Net Ecosystem Exchange(NEE) of forest ecosystem were obtained during a year.The ecosystem began to absorb CO2 at about 7: 00 am,and maintains in great absorption from 10:00 to 14:00,at about 17: 30,the ecosystem began to release CO2.The analysis of the relationships of NEE and forest ecosystem and environmental factors,shows that: When the PAR5 μmol/(m2·s),the relationship of NEE and PAR has no significant correlation in different season,monthly average NEE and monthly average temperature in canopy had linear relationship.