Study On Carbon Neutral Land Use And Land Space Optimization In Beijing-Tianjin-Hebei Region

In the context of global warming and other prominent ecological and environmental issues,carbon emission reduction and carbon sink increase have become the consensus of the international community.Therefore,China has put forward the long-term goal of reaching the carbon peak by 2030 and achieving carbon neutrality by 2060.As the second largest source of carbon emissions,land plays an important role in achieving the goal of carbon peaking and carbon neutrality.The Beijing-Tianjin-Hebei region,as a rapid development area of industrialization and urbanization in the north,is characterized by continuous expansion of construction land,drastic land development and huge energy consumption,which not only brings growth to economic development,but also increases regional carbon emission pressure.Therefore,based on the five periods of land use data and socio-economic data of 2000,2005,2010,2015 and 2020,this paper studies the land use change of Beijing,Tianjin and Hebei cities in the past 20 years.The IPCC carbon emission coefficient method was used to calculate the carbon budget of different land use types in Beijing,Tianjin and Hebei,and analyze the spatio-temporal changes and the carbon neutrality and spatio-temporal changes formed by the sum of the two.On this basis,the carbon neutrality was partitioned according to the carbon emission contribution rate and the ecological carrying coefficient of carbon absorption.At the same time,combined with the main function regionalization of the three provinces and cities of Beijing,Tianjin and Hebei and the actual situation of each city in Beijing,Tianjin and Hebei,the differentiated regional spatial optimization scheme is proposed respectively.The results show that:(1)From 2000 to 2020,the land use types in the Beijing-Tianjin-Hebei region were mainly cultivated land and woodland,and both the quantity and structure of land use had changed to a certain extent.Among them,the area of construction land increased significantly,the area of cultivated land decreased significantly,the area of woodland,grassland and unused land decreased slowly,and the area of water showed a fluctuating growth state.The area of cultivated land changed the most,while that of unused land changed the least,followed by grassland,construction land,forest land and water area.In the past 20 years,the diversification degree of land use was generally above the level.(2)The carbon source and carbon sink capacity of different land use types in the cities of Beijing,Tianjin and Hebei are different.The carbon source mainly comes from construction land and cultivated land,while the carbon sink mainly comes from woodland and grassland.The carbon storage of woodland is the largest,while that of unused land and water is the smallest.Beijing,Tianjin and Tangshan were always the largest carbon sources,accounting for 56% of the total carbon sources,while Chengde and Zhangjiakou were always the largest carbon sinks,accounting for 58% of the total carbon sinks.(3)From 2000 to 2020,the carbon emission and carbon neutrality of land use in the cities of Beijing,Tianjin and Hebei showed a trend of increasing and accelerating year by year,showing a spatial distribution characteristic of decreasing from southeast to northwest,and the carbon emission and carbon neutrality of the cities with higher GDP were the most prominent.The carbon uptake of land use decreased slowly year by year,and the spatial distribution showed an increasing trend from southeast to northwest.The high value area was distributed in the northern Hebei mountain and Bashang plateau,while the low value area was distributed in the low-lying plain area.(4)The Beijing-Tianjin-Hebei of 13 city is divided into six national spatial partition,low carbon development respectively-producing agricultural products(Baoding),carbon sinks function-key ecological function areas(Zhangjiakou and Chengde city),carbon sinks function-optimized development zone(Qinhuangdao),the carbon intensity control-optimized development zone(Beijing,Tianjin,Langfang),High carbon optimization Key development zone(Shijiazhuang,Handan,Xingtai,Hengshui),high carbon optimization-optimization development zone(Tangshan City,Cangzhou City).In order to achieve the goal of carbon neutrality,the implementation of carbon reduction and increase of carbon sink is the key.