关键词: 湿地, 芦苇, 涡动相关, 碳通量, 感热通量, 潜热通量

Abstract: The dynamics of carbon flux,sensible heat flux and latent heat flux of Phragmites ecosystem were analyzed based on long term field observation data in Panjin wetland from May 26,2004 to Oct.15,2005.The results indicated that reed wetland was a strong carbon sink.The reed wetland absorbed carbon about 13.32 t CO_2/hm~2 in 2005,and the values of diurnal mean sensible heat flux and latent heat flux were 2464 kJ/ m~2 and 3880 kJ/m~2 in 2005,respectively.The mean Bowen ratio of daily cumulation from June to September in both 2004 and 2005 was about 0.15.The diurnal patterns of carbon flux,sensible heat flux and latent heat flux in reed wetland were single kurtosis and single vale,and the maximum value appeared at noon.The absolute flux values of Phragmites in growth season during daytime were higher than those during nighttime,and carbon was absorbed in daytime and emitted in nighttime.The annual average diurnal pattern of carbon dioxide concentration was also single kurtosis and single vale.The concentration became strong in nighttime and would reach maximum value near sunrise,then dropped down rapidly,and increased again on dusk.In reed wetland,the value of annual average sensible heat flux was positive in daytime and negative in nighttime,but the value of annual average latent heat flux was positive in all day different with that of forest ecosystems.The seasonal changes were obvious.In winter,the diurnal values of CO_2 flux had few changes,and the values were close to zero.The sensible heat flux was upwards as a whole,and the values in spring were higher than those in growth season.The value of latent heat flux was minimum and near zero in winter,then increased obviously in spring,and reached maximum in growth season.