The Review of Studies on Stand Basal Area Growth Model

Stand basal area growth model is a main component of stand growth and yield prediction model system.Based on the analysis of the common stand basal area growth model such as Richards model and Schumacher model,four important questions in study on stand basal area growth model are summarized as follows:(1)Three variables should be included in the model i.e.site quality index,age,and stand density index.(2)Thinned and unthinned stand growth model should be considered at the same time.Furthermore,the method of index of suppression used for basal area prediction for thinned stands is introduced in detail.(3)The construction of thinning index needs stand factors before thinning and after thinning.(4)The proposed model should have the desirable properties,such as mechanism, asymptotic property,compatibility,monotonicity,and the invariance for projection length.