Research On Decarbonization Of Land Use In Changsha City

Since the Industrial Revolution, the dioxide carbon content in the atmosphere has increased nearly the30%by the result of human activities. As the base for all socio-economic activities of humans, land resource is not only the carrier of carbon emissions, but also provide a surface for terrestrial ecosystems to sink carbon. Studies have shown that land use has contributed much to the increasing of global carbon dioxide, which of the extent is only after the combustion of fossil fuels. Land use is the most important factor of affecting urban carbon cycle and regional carbon cycle,while regional carbon cycle is influenced by land use model,land use structure,land use intensity.Currently,Changsha is in the possess of quickly urbanization and the land use change is sharply.The analysis of anthropogenic carbon emissions and carbon sink of terrestrial ecosystem can help to quantifying the net carbon emissions in Changsha city and exploring low-carbon land use strategies,which is an important way to promote both economy and the environment.This paper selects Changsha city as the study area, and established a conceptual system of low-carbon land use, which contains two subsystems-"carbon source" system and "carbon sink" system. Each system contains different indicators, by these indicators the paper estimates the net carbon emissions of land use in Changsha city form2009to2012, makes maps of carbon footprints of land use in Changsha, and analysis the correlation of the growth of carbon emissions and the development of economy of Changsha city. The research results shows that:first, the carbon source system includes the emissions of industry land, urban living land and rural living land and transportation land,the living land is the highest carbon emission; the carbon sink system includes farmland, forest land, garden land, urban green land and meadow land. Farmland absorbs the most of carbon dioxide. Second, the estimation method of carbon source and carbon sink is established. It estimates that the net carbon emissions in Changsha city is7,036,200tons, while the net carbon emissions in Changsha is10,723,600tons. The average annual growth rate is9.54%.It is demonstrated that the carbon budget is unbalanced, and the unbalance is growing gradually. Third, it carries out the decoupling analysis between the economic development and carbon emissions in Changsha by the Tapio decoupling index. As the result shows that it is a weak decoupled stated.The best strategies of low carbon oriented land use are strenthening the reducing the carbon source and enhancing the carbon sink function,optimizing land use structure.Thus it can make the goal of low-carbon land use come true.