湖北林业科技

poplar plantations in Tianmen，Qianjiang and xiantao was taken as the research object，and data from48sam- ple plots in2022were collected，measuring the growth of731poplar trees as modeling data . Nine commonly used DBH- tree height models were fitted using the R software . The best model was determined based on six evaluation indicators：co- efficient of determination（R2），root mean square error（RMSE），sum of squared residuals（SSE），mean absolute error （MAE），mean relative error（MRE），and Akaike information criterion（AIC）. The predictive ability of the best model was tested using DBHand tree height data from10fixed plots in poplar plantations in Tianqianmian area in2021，which had similar site conditions and initial stocking density. The results showed that among1to 9models，the4th model（quadratic polynomial）provides the best fitting result. The expression of this model wasH —1. 0410D— 0. 0122D2 . It can serve as the fundamental model for diameter-height relationship in poplar plantations in Tianmen，Qianjiang and xiantao .