Price Charles A, Schroeder Todd A, Branoff Benjamin, Marcano-Vega Humfredo, Pillot-Torres Nicole, Chaudry Morgan, Ross Michael, Papeș Monica, Van Bloem Skip
Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, United States of America.
National Institute for Modeling Biological Systems, University of Tennessee, Knoxville, Tennessee, United States of America.
PLoS One. 2025 Sep 11;20(9):e0323926. doi: 10.1371/journal.pone.0323926. eCollection 2025.
Estimating the biomass of terrestrial forests generally, and mangrove forests in particular, is an area of considerable interest. Most approaches rely on empirically derived allometric models to predict tree biomass. The single parameter with the strongest predictive ability in most studies is diameter at breast height (DBH); however the use of DBH arose primarily out of convenience, not from an analysis of tree form. While DBH explains a lot of variability in other tree metrics such as height or above ground biomass, its utility in smaller species is uncertain. Here we used measurements from 302 destructively sampled mangrove trees of four species to test which of three bole diameter measurements, basal stem diameter (BSD), diameter at 30 cm (D30), and DBH, is the best predictor of aboveground biomass. D30 had the highest mean coefficient of determination (R2) and lowest mean root mean squared error (RMSE) across all site/species combinations. However, the improvement over DBH was modest, with a mean across all site/species combinations of 1.58 kg RMSE and R2 of 0.948 for D30, compared to 1.63 kg RMSE and R2 of 0.917 for DBH. Nevertheless, D30 may have utility in future studies as it allows for lower size thresholds and has better overall explanatory power than DBH.
总体而言，估算陆地森林的生物量，尤其是红树林的生物量，是一个备受关注的领域。大多数方法依靠经验得出的异速生长模型来预测树木生物量。在大多数研究中，预测能力最强的单一参数是胸径（DBH）；然而，胸径的使用主要是出于方便，而非对树木形态的分析。虽然胸径可以解释其他树木指标（如高度或地上生物量）的许多变异性，但其在较小物种中的效用尚不确定。在这里，我们使用了对四个物种的302棵经破坏性采样的红树林树木的测量数据，来测试三个树干直径测量值（基部茎干直径（BSD）、30厘米处直径（D30）和胸径）中哪一个是地上生物量的最佳预测指标。在所有地点/物种组合中，D30的平均决定系数（R2）最高，平均均方根误差（RMSE）最低。然而，与胸径相比，其改进幅度不大，在所有地点/物种组合中，D30的平均RMSE为1.58千克，R2为0.948，而胸径的平均RMSE为1.63千克，R2为0.917。尽管如此，D30在未来的研究中可能有用，因为它允许更低的尺寸阈值，并且比胸径具有更好的整体解释力。
