Greenhouse Gas Fluxes On The Water-air Interface Of Poyang Lake

Poyang Lake water-air interface of greenhouse gases (CO2, CH4, and N2O) flux observations to explore the lake’s contribution to atmospheric greenhouse gases. The results obviously showed that during measureing period the flux of CO2of Poyang Lake water-air interface had a significantly diurnal variation, when solar radiation was strong the waterbody as the sink of atmospheric CO2, at night the waterbody as the sources atmospheric CO2and the emissions of CO2in deep water experimental points greater than it was in shallow water experimental points. Spring, summer, autumn and winter average CO2flux, respectively16.52,24.31,15.91and7.28mg·m2·h-1. Analysis of the CO2flux and environmental factors, temperature, wind speed, sediment, total nitrogen, sediment organic matter and pH of the water-air interface CO2flux had a significant impact.No apparent diurnal variation of CH4flux measurements during the Poyang Lake water-air interface, all the experimental points were the source of atmospheric CH4. Spring, summer, autumn and winter CH4flux average were0.25,0.51.0.29and0.07mg·m-2·h-1. Found through analysis of environmental factors, water-air interface CH4flux and temperature, wind speed and sediment organic carbon, water ammonium nitrogen had a significant positive correlation between a significant negative correlation with water DOC.N2O flux analysis of results found:Poyang Lake water-air interface N2O fluxes diurnal variation was not obvious, all the experimental points are the source of atmospheric N2O. Spring, summer. autumn and winter average N2O fluxes were2.86.3.87.1.5and2.25μg·m-2·h-1. Correlation analysis. the Poyang Lake water-air interface N2O flux increased with the elevated temperature, sediment, total nitrogen and pH. and reduce sediment C/N ratio and electrical conductivity increased.