Modeling Survival, Yield, Volume Partitioning and Their Response to Thinning for Longleaf Pine Plantations
2012
Gonzalez-Benecke, Carlos A. | Gezan, Salvador A. | Leduc, Daniel J. | Martin, Timothy A. | Cropper, Wendell P. | Samuelson, Lisa J.
Longleaf pine (Pinus palustris Mill.) is an important tree species of the southeast U.S. Currently there is no comprehensive stand-level growth and yield model for the species. The model system described here estimates site index (SI) if dominant height (Hdₒₘ) and stand age are known (inversely, the model can project Hdₒₘ at any given age if SI is known). The survival (N) equation was dependent on stand age and Hdₒₘ, predicting greater mortality on stands with larger Hdₒₘ. The function that predicts stand basal area (BA) for unthinned stands was dependent on N and Hdₒₘ. For thinned stands BA was predicted with a competition index that was dependent on stand age. The function that best predicted stand stem volume (outside or inside bark) was dependent on BA and Hdₒₘ. All functions performed well for a wide range of stand ages and productivity, with coefficients of determination ranging between 0.946 (BA) and 0.998 (N). We also developed equations to estimate merchantable volume yield consisting of different combinations of threshold diameter at breast height and top diameter for longleaf pine stands. The equations presented in this study performed similarly or slightly better than other reported models to estimate future N, Hdₒₘ and BA. The system presented here provides important new tools for supporting future longleaf pine management and research.
显示更多 [+] 显示较少 [-]