Estimation Of Xilin Gol Grassland Biomass Carbon Stock

This paper based on the vegetation growing season (5-9months)MODIS-NDVI data and meteorological data of XilinGol grassland in2002,2005and2009year, use the CASA model and plant bitter loss model, toestimate the Aboveground biomass Carbon Stock of XilinGol grassland. Andaccording to the proportion of Aboveground biomass and Belowgroundbiomass, calculate the below-ground biomass Carbon Stock. Finally, analyzethe spatial distribution pattern and dynamic changes of Carbon Stock ofresearch area. The results showed that:1. The Carbon Stock and Carbon Density of XilinGol grassland in recentyearsIn2002, the Aboveground, Belowground and the total biomass CarbonDensity of the research area was0.05、0.23、0.28kgC/m2; And theAboveground, Belowground and the total biomass Carbon Stock of theresearch area was8.68、40.64、49.33Tg(1Tg=1×1012g). Thus, theBelowground biomass Carbon Stock was about4.68times bigger than theAboveground biomass Carbon Stock。In2005, the Aboveground, Belowground and the total biomass CarbonDensity of the research area was0.05、0.21、0.26kgC/m2; And theAboveground, Belowground and the total biomass Carbon Stock of theresearch area was8.09、37.48、45.58Tg. Thus, the Belowground biomassCarbon Stock was about4.63times bigger than the Aboveground biomassCarbon Stock.In2009, the Aboveground, Belowground and the total biomass CarbonDensity of the research area was0.04、0.21、0.25kgC/m2; And theAboveground, Belowground and the total biomass Carbon Stock of theresearch area was7.61、36.04、43.64Tg. Thus, the Belowground biomass Carbon Stock was about4.74times bigger than the Aboveground biomassCarbon Stock.2. The spatial distribution of biomass Carbon Stock in research areaThe spatial distribution of XilinGol grassland Aboveground,Belowground and the total biomass Carbon Stock showed features of gradualincrease from west to east. The largest Carbon Stock was appeared in thenortheast, and the minimum Carbon Stock was in the western region.Strictlyspeaking, the distribution pattern of XilinGol grassland biomass Carbon Stockwas followed by high-medium-high-low characteristics from northeast tosoutheast.3. The Carbon Stock of different grassland types in XilinGolCarbon Stock of the typical steppe is largest in XilinGol, accounting for75%of the total biomass Carbon Stock; and the meadow steppe is in thesecond place, about18%of the total biomass Carbon Stock, but the area ofmeadow steppe is only accounted for14%of XilinGol league. The CarbonStock of desert steppe is minimum, only7%of the total Carbon Stock.4. The dynamic changes of XilinGol grassland biomass Carbon Stock（1）The monthly change trend of biomass Carbon StockThe monthly change analysis shows that there are certain rules for themonthly change trend of XilinGol grassland biomass Carbon Stock. But, thereare differences between the different years and different grassland type also.In2002and2005year, the monthly change of meadow and typical steppe isshowed as the characteristics of single peak. The peak value is appeared inJuly. But in2009, the monthly change feature is gradually decreased influctuation. And to desert steppe, there is no obvious common monthlychange trend in2002,2005and2009year.（2）The annual change trend of biomass Carbon StockBy the annual analysis we can see that there are weak decrease trend ofthe Aboveground, Belowground and the total biomass Carbon Stockbetween2002-2009, and the rate of change between2002-2005is fatter thanchange between2005-2009.The Belowground biomass Carbon Stock reduced 7.77%in2002-2005, and reduced3.86%in2005-2009. The AbovegroundCarbon Stock reduced6.8%in2002-2005, reduced6.05%in2005-2009. Thetotal biomass Carbon Stock reduced7.6%in2002-2005, and reduced4.25%in2005-2009.5. The space change characteristics of XilinGol grassland biomassCarbon StockBy analysis we know that there are obvious regional differences inannual change of XilinGol grassland biomass Carbon Stock. In the westernregion, there are increasing characteristic in fluctuation, and decreasing influctuation in the eastern region.