Assessment Of Forest Carbon Sequestration Capacity In Wuhan City

Forest ecosystem is the largest carbon pool in terrestrial ecosystem.It can regulate global carbon balance and slow down the rise of greenhouse gases such as CO₂ by utilizing the absorption and accumulation of carbon dioxide by vegetation in forest ecosystem.Therefore,it is necessary to scientifically estimate the biomass and carbon storage of regional forest ecosystem,quantitatively describe and analyze its current situation and dynamic change,and reveal the inherent law.It provides decision support for regional ecological construction and protection of typical vegetation types.Based on the data of the fourth forest resources inventory in Wuhan,the forest biomass in Wuhan was predicted by IPCC method,continuous function factor method and weighted function regression model method respectively.Through comparative analysis,continuous function factor method was selected as the estimation method of this study to evaluate the carbon sink capacity of forests in Wuhan.In addition,this paper evaluates the carbon storage and carbon density of sub-regions,sub-tree species?groups?in Wuhan.The results show that:?1?Based on the data of the fourth continuous forest inventory in Wuhan,the total forest biomass in Wuhan was assessed by the continuous function factor method.The total forest biomass in Wuhan was 4.568 million tons,the biomass per unit area was39.7 t/hm²,and the average carbon density was 19.65 tC/hm².Li Haikui and other studies show that the average carbon density of forests in Hubei Province is 23.74tC/hm².In contrast,the average carbon storage density of forests in Wuhan City is relatively low.In the future,we should increase afforestation,strengthen forest management,improve forest structure,increase carbon storage of forest ecosystems,and contribute to global carbon sinks.?2?Huangpi District,the regional city with the highest forest biomass,accounted for 45.89%of the total forest biomass in Wuhan,followed by Jiangxia District,accounting for 31.8%of the total forest biomass in Wuhan.East-West Lake and Caidian are the least,accounting for only about 5%of the forest biomass in Wuhan.There are great differences in the distribution of urban forests in the central and suburban areas of Wuhan.Generally speaking,most of the large-scale urban forests are distributed in the suburbs,but the number of urban forests in the central area is insufficient.Wuhan needs to start with the forest distribution pattern of the whole city of Wuhan,considering the spatial and functional attributes of different patterns,so as to be holistic and systematic.Optimize the distribution pattern of urban forests,better play the ecological function of urban forests,and contribute to urban carbon sinks.?3?Young forests,middle-aged forests and near-mature forests account for 87%of the total biomass.At present,middle-aged forests have an advantage in carbon storage of forest arbor forests,followed by near-mature forests and middle-aged forests.There is a significant gap between mature forests and over-mature forests in the proportion of carbon storage compared with the former two.Although this gap will gradually narrow over time,it may be morained for a longer period of time thereafter.Carbon storage in forest and arbor forests maintained the distribution characteristics among these age groups.?4?The biomass of Pinus massoniana,Poplar and Cunninghamia lanceolata is larger,accounting for more than 69%of the total biomass.The largest biomass is Pinus massoniana,accounting for 35%of the total biomass.Poplar accounted for 20.5%of the total biomass.Coniferous forests accounted for 54.2%of the total forest biomass,broad-leaved forests accounted for 37.1%of the total forest biomass,and coniferous-broad-leaved mixed forests accounted for only about 9%of the total forest biomass.In the future,the afforestation area of coniferous and broad-leaved mixed forests will be increased and the forest structure of Wuhan will be enriched.?5?The total carbon sequestration value of forests in Wuhan is 2219.329 million yuan.Among all the dominant tree species?groups?,Pinus massoniana creates the highest carbon sequestration value for Wuhan.Among all age groups,the middle-aged forest contributed the most to Wuhan,and the difference between young forest and near-mature forest was not far.In all areas of Wuhan,Huangpi District has made a significant contribution to the carbon sink of Wuhan.In the future,the East-West Lake Region and Caidian District should pay attention to afforestation and increase forest area.