Study On Planting Design Of Urban Green Space To Improve The Efficiency Of Carbon Sink

Global climate change has become the biggest environmental challenge to human development.Greenhouse gas emissions caused by man-made activities have been the main cause of global warming since the mid-20 th century.Urban areas are the places where fossil energy utilization and greenhouse gas emissions are concentrated,as well as the areas where global climate change has a significant impact on human beings.Reducing CO2 emissions within urban boundaries and enhancing carbon sinks are considered as two key countermeasures to adapt to climate change and mitigate the subsequent impacts of climate issues on urban areas.As the only ecological space near nature in the city,urban green space plays an important role in maintaining carbon balance,human health and ecosystem services.In terms of adaptation and mitigation of climate problems,green space can directly sequester carbon and release oxygen.Through photosynthesis,plants in green space can absorb greenhouse gases such as CO2 and convert them into organic carbon for storage as biomass,thus carrying out long-term natural carbon sink storage.At present,how to accurately regulate the physical and chemical indicators of plant communities in urban green space,so as to achieve more efficient and sustainable carbon absorption is still a challenging issue in the industry.Based on this background,this paper will take the plant community in urban green space as the research object,explore the influence of its characteristic indicators on the carbon sink benefit of green space,and carry out effective intervention on the characteristic indicators through planting design,in order to provide reference for the fine management and control of the carbon sink benefit of urban green space,and expand the green way to practice carbon neutrality.The study took the attached greenbelt of Nanjing Forestry University as an example and took the carbon sink benefit of the plant community in the greenbelt as the research object.First,the representative plant communities in the green space were investigated,and the specification parameters of main plants were determined,so as to calculate the distribution of characteristic indicators of the plant communities in the green space.Secondly,the carbon sequestration benefits of each plant community were quantitatively calculated,and the relationship between community characteristics and carbon sequestration capacity was discussed by correlation analysis,regression analysis and cluster analysis.Finally,the planting design model of plants with high carbon sink capacity was summarized,and the current plant community was optimized for planting design.The details include the following:(1)Statistical characteristics of green space plant communities.According to the plot division and plant community classification,a certain number of plant communities in the region were selected for study.The number,DBH,plant height,crown width,leaf area index,photosynthetic rate and other individual characteristics of different plant communities were measured and collected,as well as the community characteristics of different plant communities,such as the ratio of grass to irrigation,canopy density,diameter class structure,planting density,etc.,and mathematical induction was carried out to obtain the planting design situation of the current green space.(2)The carbon sink capacity of green space plant community was calculated.According to the selected carbon sink benefit index,combined with assimilation quantity method,biomass method and relevant calculation formula,the daily carbon sequestration and carbon storage of individual plants and daily carbon sequestration and carbon storage per unit area of plant community in the green space were calculated respectively,so as to quantify the carbon sink benefit of each green space plant community sample plot,laying the foundation for subsequent data analysis.(3)Explore the relationship between plant community characteristics and carbon sink.SPSS software was used to conduct correlation analysis and regression analysis on each characteristic factor of individual and community of green space plants and their corresponding carbon sink benefits,respectively exploring the characteristic factors significantly related to the carbon sink benefits of individual and community of plants,determining their correlation ranking,drawing fitting curve,and then classifying the carbon sink benefit levels by cluster analysis.Furthermore,the characteristics of high carbon sink benefit of green space plant community were summarized.(4)Optimize the planting design model of plant community.For the green space plant community with poor carbon sink benefit at present,according to the summarized characteristics of the plant community with high carbon sink benefit,the dominant tree species of carbon sink and vegetation community structure regulation were selected to optimize the planting design.By comparing the changes of carbon sink benefit before and after optimization,the planting design mode of urban green space with high carbon sink suitable for Nanjing was finally concluded.To achieve sustainable greenbelt long-term carbon sinks.