Abstract:

Taking Caragana sinica,a natural shrub distributed in the central Tianshan Mountains,as the study object,and 40 sample trees were collected from Hutubi Branch and soil samples were collected.Firstly,the correlation analysis of factors affecting biomass was carried out.Then,the canopy area of natural Caragana was used as the independent variable,and the aboveground biomass was used as the dependent variable.The aboveground biological model was fitted by linear,quadratic,power and exponential regression;Finally,the fitting results were compared and analyzed.The results showed that the aboveground biomass of natural Caragana was positively correlated with plant height,average branch length,crown area,soil organic carbon and hydrolytic nitrogen,and positively correlated with average basal diameter and soil available phosphorus,but had no significant correlation with soil available potassium.The optimal aboveground biomass model was the conic curve model,with a fitting accuracy of 89.54%.

Key words: the Central Tianshan Mountains, Caragana arborescens, tree crown width, aboveground biomass, model