Study on the Variation Law of DBH of Picea crassifolia in Dahekou of Qilian Mountains
Diameter at breast height(DBH)is one of the most important indicators in forestry survey,which can characterize the growth and change law of forest resources.In this paper,six fixed sample plots of Picea crassifo-lia in the eighth and ninth continuous forest resources inventory in Minle County,Zhangye City,Gansu Province were taken as the research objects.By analyzing the correlation between the DBH data of each tree in the two pe-riods,the purpose was to reveal the variation law of DBH of Picea crassifolia.The results of regression analysis showed that the optimal fitting formula of late DBH and early DBH of Picea crassifolia was quadratic model(Dafter=0.369+1.038Dbefore-0.001 D2before.Dafter is the DBH of the ninth continuous inventory,that is,the late DBH;Dbefore is the DBH of the eighth continuous inventory,that is,the before DBH.The calculation results of the model equa-tion are in good agreement with the actual measured DBH data in 2023.The quadratic model can better reflect the growth and change relationship of Picea crassifolia DBH in Qilian Mountains,which will provide a theoretical ba-sis for the future prediction of Picea crassifolia population.
万方数据
维普
