利用第八次全国森林资源清查内蒙古自治区2013年清查的12万株保留木前后期实测胸径数据,分内蒙地方和内蒙森工2个建模总体,建立了各个树种组的立木胸径生长率模型。对内蒙地方建模总体中分布范围较广的树种组,利用哑变量建模方法,建立了适用于东、中、西部不同区域的胸径生长率模型。结果表明,利用各个树种组的胸径生长率模型预估林木的后期胸径时,绝大多数树种组的确定系数R ²能达到0.96以上,平均预估误差MPE在1%以下。所建胸径生长率模型可为第九次全国森林资源清查内蒙古自治区2018年清查外业调查时判定林木胸径生长量是否过大提供定量依据。

Based on the mensuration data of diameter at breast height (DBH) from about 120 thousand survival trees in Inner Mongolian forest inventory 2013 of the 8th National Forest Inventory in China,individual tree DBH growth rate models for major tree species were developed for two modeling populations,Inner Mongolian Autonomous Region (I) and Inner Mongolian Key State-owned Forest Management Bureau of Daxing’anling (II).For some tree species with a wide range of distribution in modeling population I,dummy modeling approach was used to develop DBH growth rate models suitable for eastern,central and western regions.The results showed that determination coefficients (R ²) for most tree species were more than 0.96,and mean prediction errors (MPE) were less than 1%,when DBH growth rate models were used to estimate diameters at the end of interval period.The developed DBH growth rate models would provide quantitative basis for determining whether the DBH growth of trees is too large in field survey of Inner Mongolian forest inventory of the 9th National Forest Inventory.