Estimation Of Carbon Storage Of Arbor Forest Based On The Forest Resource Inventory Data

Forest is one of the most abundant resources in nature and plays an important role in the global carbon cycle.The carbon stock of forest tree layer is the dominant part in the carbon stock of forest ecosystem.Accurate estimation of national carbon stock can provide the basis for forest scientific management.Based on the sampling data of the Ninth National Forest Resources Inventory,this paper divides the arbor forest into 37 forest types,establishes and compares two kinds of accumulation models for each forest type,estimates the carbon reserves of arbor forest in China by using the optimal model,and focuses on analyzing the differences of carbon reserves of different forest types,different age groups and regions,and explores the environmental factors Effect of seed on carbon density of arbor forest.?1?In the established models,the accuracies of the volume model related to the tree height and the forest basal area is higher.The R² of the model is between 0.55-0.99,the bias%is between-1.61-10.67%,and the RMSE%of the volume prediction is between 5.30-57.97%,which can be used to estimate the volume of forest.?2?The carbon stock of arbor forest was estimated by the above model.From the perspective of forest types,the average carbon density of each forest type is 59.39 Mg ha^-1,the carbon density of Alpine pine,Phoebe,fir is the highest,the carbon density of other pine,red pine,eucalyptus is the lowest;oak,larch and fir are the important contributors of carbon reserves of arbor forest,the sum of the three accounts for 24.63%of total carbon reserves of arbor forest.From the age group,the average carbon density of each age group is 64.60 Mg ha^-1,and the carbon density increases with the age of arbor forest.The over mature forest with the largest carbon density is 86.73 Mg ha^-1,and the young forest with the smallest carbon density is 41.89 Mg ha^-1;the middle age forest has the largest carbon storage,and the over mature forest has the smallest carbon storage,accounting for 29.80%and 9.81%of the total carbon storage,respectively.From the regional point of view,the average carbon density of arbor forest in each region is 50.85 Mg ha^-1,and the carbon density from high to low is southwest,East China,northwest,East China,northeast and North China,respectively.The southwest region with the largest carbon density is 56.52 Mg ha^-1,and the North China region with the smallest carbon density is 48.76 Mg ha^-1 From high to low,the carbon reserves are respectively southwest,northeast,Central South,northwest,East China and North China,which together account for 60.68%of the national carbon reserves.?3?Longitude,latitude,altitude,soil thickness,slope,aspect,slope position,temperature and rainfall were selected to explore their effects on carbon density.Among them,the importance of variables from large to small are longitude,latitude,soil thickness,rainfall,slope,altitude,temperature,slope position and slope direction.The carbon density of arbor forest has no significant increase or decrease trend in all longitudes and latitudes;the carbon density increases gradually with the elevation;the carbon density is the highest in the semi sunny slope and the lowest in the semi cloudy slope;the higher the carbon density is,the higher the carbon density is;the trend of the carbon density with the increase of slope is to increase first and then decrease;the thicker the soil is,the lower the carbon density is;the carbon density with the temperature of air The increase of rainfall was first increased and then decreased.