Analysis On The Change And Driving Force Of Carbon Storage Of Main Land Use Types In Chongming Island From 2009 To 2018

The acceleration of the urbanization process has changed the composition and structure of terrestrial ecosystems,and how does this change affect vegetation carbon storage.This study takes Chongming Island as the research object,based on the 2009 and 2018 fixed-point field survey data,analyzed the vegetation carbon storage and carbon density of the three major land use types in 2009 and 2018,including cultivated land,forest land and construction land;according to 2009 and The area of cultivated land,forest land and construction land and the average carbon density of sample points of cultivated land,forest land and construction land in 2018 estimate the total carbon storage of cultivated land,forest land and construction land;and the changes in carbon stocks of cultivated land,forest land and construction land in 2009 and 2018 The natural drivers and social drivers were analyzed.This study provides a basis for the construction of ecological urbanization and sustainable development of cities.The main conclusions are as follows:1.Analysis of land use type change: The statistics of the cultivated land,forest land,construction land,water body,and unused land area of Chongming Island in2009 and 2018 are shown by ENVI: The construction land,forest land,water body,and unused land area of Chongming Island in 2018 is higher than that of 2009 The area increased,and the area increased by 96.75km2,53.88km2,26.02km2,10.89km2respectively;while the cultivated land area decreased,the area decreased by43.29km2.2.Vegetation overview: By analyzing the vegetation of the three main land-use types of cultivated land,forest land and construction land from 2009 to 2018,Chongming Island has the most forest vegetation types in 2009 and 2018,followed by construction land and cultivated land.Cultivated land and woodland are mainly dominated by deciduous trees and deciduous shrubs,while construction land is dominated by deciduous trees and evergreen shrubs.In 2018,compared with 2009,cultivated land mainly added Guangyulan,Luan tree,Ligustrum lucidum,Hibiscus and other tree species.Guangyulan,Eucommia,Luanshu and other tree species.3.Analysis of carbon storage by land use types: In 2009,the vegetation carbon storage of Chongming Island sample sites totaled 346.35 Mg,and in 2018,the vegetation carbon storage of Chongming Island sample sites totaled 1230.87 Mg.In2009 and 2018,the carbon reserves of vegetation at various sites of cultivated land,forest land and construction land on Chongming Island were in the order of forest land,construction land and cultivated land.In 2009,the average carbon density of cultivated land,forest land,and construction land samples was 36.33Mg/hm2,176.26Mg/hm2,and 38.46Mg/hm2,respectively.In 2018,the average carbon density of cultivated land,forest land,and construction land samples was 181.36 Mg/hm2,450.46 Mg/hm2,222.65 Mg/hm2.According to the vegetation density and area of??each land use type,the total carbon storage can be estimated: the total carbon storage of cultivated land,forest land and construction land in 2009 was 3.16 kg,4.12 kg,0.55kg;the total carbon storage of cultivated land,forest land and construction land was 15.03 in 2018 kg,12.96 kg,5.31 kg.4.Analysis of the driving force of carbon storage by land use type:(1)The impact of vegetation life style on vegetation carbon storage: The increase in the number of trees and shrubs in cultivated land,forest land and construction land in 2018 resulted in the increase in the number of trees in cultivated land,forest land and construction land in 2018.important reason.(2)Impact of vegetation characteristics on carbon storage: In 2009 and 2018,the average vegetation carbon storage in forest land was directly and positively correlated with tree breast diameter and tree height,and directly negatively correlated with vegetation and vegetation density.In 2009 and 2018,the average vegetation carbon storage of construction land was directly related to the tree breast diameter and tree height,and indirectly related to the tree crown.(3)The impact of social factors on vegetation carbon storage: mainly explained by changes in vegetation types,changes in land use types,and adjustment of vegetation structure caused by human factors.The results show that: lead to cultivated land,forest land and construction land from 2009 to 2018 The driving force for the change of vegetation carbon storage is mainly the driving force that causes the increase of vegetation carbon storage:Analysis of the social driving force for the increase of vegetation carbon storage incultivated land,forest land and construction land shows that: the increase in the number of vegetation,the change of land type,the change and increase of vegetation type are all social driving forces that lead to the increase in vegetation carbon storage in cultivated land,forest land and construction land Among them,the change and increase of vegetation types are the main social driving forces that lead to changes in arable land carbon storage.(4)Analysis of main driving forces for changes in vegetation carbon storage of major land use types Based on the structural equation model,the driving force for the change of vegetation carbon storage in cultivated land,forest land and construction land is analyzed: The main driving force for the change in forest vegetation carbon storage from 2009 to 2018 is the change in tree breast diameter,which is a natural factor.The establishment of a structural equation model for the changes in vegetation carbon storage in Chongming Island shows that the changes in vegetation carbon storage in Chongming Island from 2009 to 2018 were affected by changes in the number of trees and changes in tree breast diameter,of which the change in the number of trees is the main driving force.