Temporal And Spatial Pattern Evolution Of Carbon Source/Sink In Guangxi Beibu Gulf Economic Zone And Its Human Factors

Based on the classification of land use and the accounting method and system based on the IPCC greenhouse gas inventory guidelines,the remote sensing geographic information system(rs-gis)is applied to monitor and analyze the carbon source / sink classification and spatial-temporal pattern evolution of Beibu Gulf Economic Zone from 1995 to 2018,Based on agricultural land and non-agricultural construction land,this paper establishes a log mean Di’s index(LMDI)decomposition model to quantitatively analyze the impact of human factors such as population,economy,industry,energy and technology level on carbon emissions in Beibu Gulf Economic Zone.The results show that: 1(1)Regional carbon cycle is one of the important hot spots in the context of global change and low-carbon development.As a high concentration of population and economic activities,urban agglomeration is an important driving force of global carbon cycle.Beibu Gulf Economic Zone,as an important economic development area and emerging urban agglomeration in Guangxi,is developing rapidly in industrialization and urbanization.It is of great value to study the evolution of its carbon / sink spatial-temporal pattern and its human factors.(2)From 1995 to 2018,the carbon emissions of Guangxi Beibu Gulf Economic Zone increased from 14.3172 million tons to 96.2371 million tons;Carbon absorption increased from17.3361 million tons to 24.4626 million tons.The net carbon emission is negative before 2005,Guangxi Beibu Gulf Economic Zone belongs to carbon sink area;It became a carbon source area after 2005.(3)In the evolution of carbon source / sink time series,although the carbon absorption increased year by year from 1995 to 2018,the range was not obvious.In contrast,the increase of carbon emission changed significantly,especially from 2005;Compared with construction land,the increase of carbon emission of cultivated land is relatively flat.(4)In the spatial pattern of carbon source / sink,the carbon emissions from 1995 to 2000 were mainly distributed in Nanning and Yulin,and the high value areas of carbon emissions appeared in the north and east of the study area.In 2005,Nanning,Yulin and Fangchenggang became high carbon emission areas.From 2010,the high value area of carbon emissions moved to the south of the economic zone,which is basically consistent with the moving track of the economic center of Guangxi Beibu Gulf Economic Zone;The main contribution area of carbon absorption in 1995 was Yulin City,followed by Nanning city.In 2000,the high value areas of carbon absorption were mainly distributed in the north and east of the study area.After 2000,the distribution of carbon absorption tended to be balanced.(5)The overall impact of the seven human impact factors on net carbon emissions is positive in the period of 1995-2018.During 1995-2000,the land use structure effect is the main human factor of carbon emission reduction in Guangxi Beibu Gulf Economic Zone.At the same time,the land use structure effect and per capita energy consumption effect are also the factors of carbon emission reduction.The land use efficiency,urban and rural economic structure and per capita energy consumption are the factors of carbon emission increase.From 2000 to 2005,land use structure is the main factor of carbon emission reduction,and land use efficiency is also the factor of carbon emission reduction;Unit energy consumption output,urban and rural economic structure,per capita energy consumption and population size are all factors leading to the increase of carbon emissions.From 2005 to 2010,land use efficiency is the main factor to reduce carbon emissions,and the output effect of unit energy consumption is the main factor to increase carbon emissions;The impact of land use structure on carbon emission reduction is also very high.Urban and rural economic institution effect,per capita energy consumption effect and population size effect are the factors that increase carbon emission.From 2010 to 2018,land use efficiency is the main factor of carbon emission reduction,land use structure effect is also the factor of carbon emission reduction,and unit energy consumption output is the main factor of carbon emission increase;Urban and rural economic structure effect,per capita energy consumption and population size are the factors that increase carbon emissions.