| The Ebinur Lake is the largest saltwater lake in Xinjiang Uygur Autonomous Region of China,which is suffering from severe environmental problems such as shrinking lake area,strong wind and sand activities,soil salinization,vegetation degeneration and climate warming.In the background of global warming and soil salinization is aggravating,the high salt lakes in arid areas of wetland soil in greenhouse gas flux research in order to further understand the wetland on the influence of the pattern of the source/sink of greenhouse gases in the atmosphere is of great significance.In this study,a study was conducted to study the soil of high-salinity Ebinur Lake wetland as the research area.Based on the 2015-2017 in January?winter?,may?spring?,August?summer?,November?fall?,the static box-gas chromatography of soil to capture CO2,CH4 and N2O,and record and determination of environmental factors.Based on the synchronous acquisition of soil spatiotemporal variation of CO2,CH4 and N2O and environmental factor analysis,revealing the lakes in arid areas,the greenhouse gas emission flux changes of wetland soil,discusses influence high Salt Lake wetland soil in greenhouse gas emissions main controlling factor,to objectively estimate the regional soil in greenhouse gas emissions and to understand the source/sink area pattern has important guiding significance.The main conclusions are as follows:?1?The high-salinity Ebinur Lake wetland is the"source"of CO2 and N2O and the"sink"of CH4.The peaks of soil CO2 and N2O flux emissions occur respectively in summer and autumn,and the lowest emission flux appears in winter.And the soil CH4 flux is a single peak curve with summer absorption peak,and the lowest absorption flux is also found in winter.?2?The changes of soil CO2 and N2O flux space are all patchy distribution.Among them,the high-value region of soil CO2 flux emission appears in the northwest?Haloxylon ammodendron-Tamarix chinensis?,and the low-value region appears in the southwest?Populus euphratica?.The N2O emission fluxes of soil show the characteristics of southeast?Populus euphratica?,northwest,northeast?Haloxylon ammodendron?and southwest.The soil CH4 flux shows a strip distribution,and the absorption value decreases successively from the north to the south.?3?Correlation analysis and principal component analysis and multiple regression analysis showed that soil temperature,air temperature and humidity,soil organic matter is high aibi lake salt lakes wetland soil CO2,CH4,N2O flux of the main factors;When soil temperature at 25?32?,25?32?,the range of 0?5?,the air temperature at 30?to 40?,30?to 40?,the range of 0?10?,relative humidity of air at 030%range,organic content,respectively,at 2040 g·kg-1,2040 g·kg-1,1020 g·kg-1 of scope,the most beneficial to soil release CO2,absorption of CH4 and N2O release;?4?The high-salinity Ebinur Lake wetland in northeast?Haloxylon ammodendron?,southeastern?Populus euphratica?,southwest?Populus euphratica?,northwest?Haloxylon ammodendron-Tamarix chinensis?GWPs were2421.96,1579.77,546.83 and 3168.19 gCO2/m2,soil comprehensive performance for the"source"of greenhouse gases,which stimulates the global warming.The comparison of CO2,CH4 and N2O fluxes of other typical ecosystems at home and abroad shows that the soil CO2,CH4 and N2O emission in the high-salinity Ebinur Lake wetland are relatively small,and its warming effect is relatively low. |
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