Land Use In The Urbanization Process Of Fuzhou City Study On The Effect Of Carbon Budget And Expenditure

Global warming restricts human development.In the process of rapid urbanization,greenhouse gas emissions from human activities,such as the burning of fossil energy and land use change,are the main causes of climate warming.Studying the effect of land use carbon budget in the process of urbanization can provide scientific reference for the reduction of carbon emissions in cities and the rational planning and layout of ecosystems.Therefore,this study takes the main urban area of Fuzhou as an example,accounts and analyzes the change status of land use carbon stocks and flux(carbon input and carbon output)in the study area from2008 to 2017 by through of the construction of land use carbon effect assessment framework and method system,and the use of land use change survey data and socio-economic data and other data.By establishing the correspondence between land use types and carbon stocks and flux,the spatiotemporal characteristics of carbon revenue and expenditure in each land use type for 10 years are obtained and analyzed.Under the background of urbanization,the influence factors of carbon revenue and expenditure effect of land use in the main urban area of Fuzhou are discussed.The main conclusions are as follows:(1)As far as the carbon stocks and carbon flux of different land use types,the largest carbon sources are urban villages and industrial and mining land,and woodland is the largest carbon sink.Carbon stocks:from 2008 to 2017,the land use type with highest annual total carbon stocks was the woodland,following by the urban villages and industrial and mining land and arable land,with their annual total carbon stocks accounting for 66.47%,18.63%and 10.65%of the total carbon stocks,respectively.The carbon stocks of cultivated land showed a downward trend,which decreased from 551.21 ten thousand tons in 2008 to 457.51 ten thousand tons in 2017,attributing to the decreasing of arable land in the main urban area of Fuzhou.The carbon stocks of urban villages and industrial and mining land increased by about 309.92 ten thousand tons in ten years,the largest increase and the largest carbon stocks per unit area,and its carbon density per unit area was as high as 153.43t/hm2in the year 2017.Carbon input:The land use type with highest annual total carbon input was woodland,the annual total carbon input value was 240.13 ten thousand tons,following by urban villages and industrial and mining land,64.75 ten thousand tons,and finally water and water conservancy facilities land and arable land,about 8%of the total carbon input.Grassland carbon input value was very low.The land use type with highest carbon input per unit area was urban villages and industrial and mining areas,about 15.77 t/hm2,indicating that the land use intensity is enormous,followed by woodland,about 10.61 t/hm2.Carbon output:The land type with highest total carbon output was urban villages and industrial and mining land,the annual total carbon output was 907.23 ten thousand tons,reached 1115.34 ten thousand tons in 2017,accounting for 62.54%of the total carbon output,is the largest carbon source,and the increase of up to 95%in the past decade,its carbon output intensity is also growing rapidly,growing from 145.71t/hm2in 2008 to 213.77 t/hm2in 2017.The annual total carbon output of woodland was 607.83 ten thousand tons.(2)In terms of the temporal trending of total carbon stocks and carbon flux,from 2008 to 2017,the land use carbon stocks,carbon input and carbon output in the main urban areas of Fuzhou were increasing year by year,and the growth of carbon output is significantly greater than that of carbon input and carbon stocks.The total annual carbon stocks of land use increased from 3903.53 ten thousand tons in 2008 to 4296.73 ten thousand tons in 2017,by about 393.2 ten thousand tons and by 10.07%;the land use carbon input was about 301.66 ten thousand tons in 2008,about 351.44 ten thousand tons in 2017,an increase of about 49.78 ten thousand tons,and increased by about 16.50%;land-use carbon output increased from 1220.42 ten thousand tons in 2008 to 2017 in 1783.41 ten thousand tons,an increase of about 46.13%.As for the spatial distribution patterns of total carbon stocks and carbon flux,the average annual carbon stocks of Fuzhou City,Changle District and Minhou County were 1178.52 ten thousand tons,711.73 ten thousand tons and 2228.32 ten thousand tons respectively from 2008 to2017.The annual average carbon input was 199.16 ten thousand tons,62.45 ten thousand tons and 174.41 ten thousand tons,respectively,and the annual average carbon output was 772.49 ten thousand tons,250.80ten thousand tons,and 555.86 ten thousand tons,respectively.The analysis shows that Minhou County has the most carbon stocks(abundant forestry resources),followed by more carbon stocks in the urban areas,while that in the Changle area was the least.the carbon output:The urban carbon output had the most carbon output,then the Minhou County,the least was the Changle area,the carbon input(2008-2010):Minhou County Carbon input had the most carbon input,the urban area was the lowest,However,from 2011 to 2017,the urban carbon input was the most,the Minhou County was the second,and the Changle region was the least distributed state.(3)The influence of urbanization factors on carbon output was relatively large,and the correlation coefficient is significantly correlated with 0.01 levels;The influence of population urbanization and land urbanization on carbon output is greater than that of economic urbanization,and all are positive effects;The correlation coefficients of proportion of construction land,proportion of urban population and per capita GDP with carbon output are the highest.By constructing a multivariate regression model with construction land area,total GDP and urban population as independent variables and net carbon emissions as dependent variables,it can be used to predict the future net carbon emissions of Fuzhou City.Moreover,when the construction land area increases by 1 km~2,urban population increases by 10000 people,and GDP increases by 100 million yuan,net carbon emissions will increase by 85180 tons.