ABSTRACT
As an important part of inland waters,small pond is a neglected source of greenhouse gas.The main objective of the study was to quantify greenhouse gas fluxes (CO2 and CH4) from small pond in the Yangtze Delta using flux-gradient method.The results showed that:â zero-gradient test indicated that the flux measurement precision for water vapor,CO2,and CH4 was 7.525 W·m-2,0.022 mg·(m2·s)-1,and 0.054 µg·(m2·s)-1,respectively.During the test period,84%,80%,and 94% of half-hourly flux data for H2O,CO2,and CH4 were higher than the zero-gradient measurement precision.â¡ Based on the measurement,the small pond was the source of CO2 and CH4 for the atmosphere in summer,the mean emission flux of CO2 and CH4 was 0.038 mg·(m2·s)-1 and 0.889 µg·(m2·s)-1,respectively.The CH4 emission fluxes from the small pond were more higher than the median value of emission for global lakes.The results indicated that greenhouse gas emission from small pond was an important part for estimating inland water greenhouse gas emissions,especially for CH4 emission.These results can provide scientific reference for making emission inventory of regional greenhouse gas.
