During the summertime of 2007/2008, carbon dioxide (CO2) and methane (CH4) fluxes across airewater
interface were investigated in the littoral zones of Lake Mochou and Lake Tuanjie, east Antarctica, using
a static chamber technique. The mean fluxes of CO2 and CH4 were 70.8 mgCO2 m2 h1 and
144.6 mgCH4 m2 h1, respectively, in the littoral zone of Lake Mochou; The mean fluxes were
36.9 mgCO2 m2 h1 and 109.8 mgCH4 m2 h1, respectively, in the littoral zone of Lake Tuanjie. Their
fluxes showed large temporal and spatial dynamics. The CO2 fluxes showed a significantly negative
correlation with daily total radiation (DTR) and a weakly negative correlation with air temperature and
water temperature, indicating that sunlight intensity controlled the magnitude of CO2 fluxes from the open
lakes. The CH4 fluxes significantly correlated with local air temperature, water table and total dissolved
solids (TDS), indicating that they were the predominant factors influencing CH4 fluxes. Summertime CO2
budgets in the littoral zones of Lake Mochou and Lake Tuanjie were estimated to be 152.9 gCO2 m2 and
79.7 gCO2 m2, respectively, and net CH4 emissions were estimated to be 312.3 mgCH4 m2 and
237.2 mgCH4 m2, respectively. Our results show that shallow, open, alga-rich lakes might be strong
summertime CO2 absorbers and small CH4 emitters during the open water in coastal Antarctica.