Assessment Of Carbon Fixation And Oxygen Release Of Green Space In Anren County

With a series of challenges and hazards brought by climate change and climate disasters to cities and the attention of the state to carbon emission and carbon neutralization,it is very important to carry out the assessment of ecological benefits of carbon and oxygen release.The study on carbon and oxygen release benefits of urban green space has become an indispensable part of urban and rural green space construction.The level of carbon sequestration and oxygen release benefit is the premise and foundation of reasonable and scientific planning of urban green space,and the core content of low-carbon city construction.As a typical county in South China,Anren County has the research ability.The level of carbon and oxygen release benefit of green space is,what level is it in the green space of Chinese cities,and how different from other cities.The specific reason for the difference is the focus of this paper.This study selects the green space of built-up area in Anren County of Hunan Province as the research object.Through the field investigation of Anren County,the data of various urban green space in the research area are extracted and calculated by using i-tree eco model.The carbon and oxygen release benefits of different tree species and different green space types are compared,and the carbon and oxygen release level of county green space is studied.The space analysis of green space in Anren County was carried out by ArcGIS software,and the factors leading to the difference of carbon fixation and oxygen release level were discussed.The main conclusions of this paper are as follows:(1)The effect of carbon fixation and oxygen release in green space is related to plant species,DBH,crown width and growth status.The high carbon and oxygen release levels of the tree species are:camphor,osmanthus,duying,ginkgo,Luan,cherry,Magnolia,Salix mandshurica,and Ziwei.Among them,the daily carbon fixation and oxygen release efficiency of unit leaf area is an important factor to measure the carbon fixation and oxygen release of plants.The results showed that Wutong,eucalyptus,elm,Indus,two Qiao Yulan,Magnolia,Huai tree,loquat,Shi Nan and cherry blossom were the most effective trees for the carbon sequestration and oxygen release efficiency of plant area in Anren county.(2)The carbon and oxygen release levels of different green space types are different,the higher the carbon and oxygen release levels are in the regions with more plants and good growth status.The benefits of carbon fixation and oxygen release in the green space of Anren County are from large to small:park green space,square green space,public management and public service green space,industrial green space,protective green space,public facilities green space,road green space,commercial service green space and residential green space.Among them,the green space and the protective green space play a leading role in the carbon sequestration and oxygen release benefits of the green space in the county of Anren County.(3)The level of carbon fixation and oxygen release in the green space of Anren County has obvious regularity in spatial distribution,and the level of carbon fixation and oxygen release is related to the type of urban green space.The carbon and oxygen release benefits of different green space types are not only related to the species,quantity,growth and health of plants,but also the carbon and oxygen release levels among various green spaces.The environment around urban green space and the connecting mode of adjacent green space are related.(4)The carbon and oxygen release benefits of the green space in Anren County are at the lower and middle level in China,are basically the same as those of northern cities such as Yantai and Zhengzhou,and there is still a certain gap between them.(5)Because of the difference between the method and the calculation method,the results of i-tree model will be lower than that of instrument,and i-tree model may underestimate the benefits of carbon fixation and oxygen release.In conclusion,Anren County,as a typical representative of the green space in southern China,has a low level of carbon fixation and oxygen release in China.Under the background of carbon neutralization,China should also accelerate the construction of a complete evaluation system of urban green space ecosystem service benefit,and improve the level of carbon fixation and oxygen release of urban green space.