摘要
Carbon dioxide partial pressures(pCO 2) and CO 2 fluxes on air water interface in different trophic level areas of Taihu Lake were calculated and corrected using alkalinity, pH, ionic strength, active coefficient, water temperature and wind speed on the basis of the data sets of monthly sampling in 1998 The mean values of pCO 2 in the hypertrophic, eutrophic, and mesotrophic areas are 1807 8±1025 8(mean±standard deviation) μatm, 416 3±207 8 μatm, and 448 5±194 0 μatm,respectively. A maximum and minimum pCO\-2 values were found in the hypertrophic(4053 7 μatm) and the eutrophic(3 2 μatm) areas. There was about one magnitude order of difference in mean CO\-2 fluxes between the hypertrophic area(27 3±17 4 mmol/(m\+2·d)) and the eutrophic(1 99±4 50 mmol/(m\+2·d)) and mesotrophic (2 22±4 31 mmol/(m\+2·d)) areas. But there was no significant difference between eutrophic and mesotrophic areas in pCO 2 and the flux of CO 2 In respect to CO 2 equilibrium, input of the rivers will obviously influence inorganic carbon distribution in the riverine estuary. An exponential relationship between the pCO 2 values and chlorophyll a concentrations was obtained( r =0 8356, n =60) in eutrophic bay. Results suggested that lake ecosystems, also may be considered as unique aggregation, which can contain and be patient of different components that have their relative independence so long as its size enough to large. A productive lake, though it has positive fluxes of CO 2 to atmosphere during the most of time, is a huge and permanent sink of carbon in terrestrial ecosystems through receiving a great quantity of carbon materials via rivers, precipitation, and biological production.
Carbon dioxide partial pressures(pCO 2) and CO 2 fluxes on air water interface in different trophic level areas of Taihu Lake were calculated and corrected using alkalinity, pH, ionic strength, active coefficient, water temperature and wind speed on the basis of the data sets of monthly sampling in 1998 The mean values of pCO 2 in the hypertrophic, eutrophic, and mesotrophic areas are 1807 8±1025 8(mean±standard deviation) μatm, 416 3±207 8 μatm, and 448 5±194 0 μatm,respectively. A maximum and minimum pCO\-2 values were found in the hypertrophic(4053 7 μatm) and the eutrophic(3 2 μatm) areas. There was about one magnitude order of difference in mean CO\-2 fluxes between the hypertrophic area(27 3±17 4 mmol/(m\+2·d)) and the eutrophic(1 99±4 50 mmol/(m\+2·d)) and mesotrophic (2 22±4 31 mmol/(m\+2·d)) areas. But there was no significant difference between eutrophic and mesotrophic areas in pCO 2 and the flux of CO 2 In respect to CO 2 equilibrium, input of the rivers will obviously influence inorganic carbon distribution in the riverine estuary. An exponential relationship between the pCO 2 values and chlorophyll a concentrations was obtained( r =0 8356, n =60) in eutrophic bay. Results suggested that lake ecosystems, also may be considered as unique aggregation, which can contain and be patient of different components that have their relative independence so long as its size enough to large. A productive lake, though it has positive fluxes of CO 2 to atmosphere during the most of time, is a huge and permanent sink of carbon in terrestrial ecosystems through receiving a great quantity of carbon materials via rivers, precipitation, and biological production.
基金
TheKnowledgeInnovationMajorProjectsofChineseAcademyofSciences(KZCX1 SW 0 1 15andKZCX1 SW 12 Ⅱ)
