Abstract:

Based on the plot survey data,the Richard equation and the Schumacher model were used to fitting.The model was fited by nonlinear metric error method,the result showed the fitting effects of the two basic models were good,and the model determination coefficients were all over 0.9.The Schumacher model was the optimal basic model.After the dummy variable was introduced into the model,the calculated coefficient of the fracture area and the accumulation model was increased to 0.9927 and 0.9972,and the model accuracy is improved to 96.1% and 97.2%.Paired t-tests were performed on the dummy variable model,and the p-values were all greater than 0.05,indicating that the model can be used to estimate the splitting area and stand volume of Pinus elliottii forests with different management measures,such as fat-harvesting and non-removing fat,in order to measure the stock of Pinus elliottii forest stand.The forest management model provides a reference.

Key words: Pinus elliottii, stand growth model, dummy variables, nonlinear measurement error, compatibility