ABSTRACT

Dry tropical forests in arid lands cover large areas in Brazil, but few studies report the total biomass stock showing the importance of height measurements, in addition to applying and comparing local and pan-tropical models. Here, we use a biomass data set of 500 trees and shrubs, covering 15 species harvested in a management plan in the state of Pernambuco, in Brazil. We seek to develop local models and compare them with the equations traditionally applied to dry forests – showing the importance of tree height measurements. Due to the non-linear relationships with the independent variables of the tree, we used a nonlinear least squares modeling technique when adjusting models, we adopted the cross-validation procedure. In summary, our above-ground biomass data set is best represented by the Schumacher-Hall equation: exp [3.5336 + 1.9126 × log (D) + 1.2438 × log (Ht)], which shows that height measurements are essential to estimate accurately biomass. The biggest prediction errors observed when testing pan-tropical models in our data demonstrated the importance of developing new local models and indicated that careful considerations should be made if generic “pan-tropical” models without height measurements are planned for application in dry forests in Brazil.

摘要

干旱地区的干旱热带森林覆盖了巴西的大片区域，但除了应用和比较当地和泛热带模型外，很少有研究报告显示高度测量重要性的总生物量存量。在这里，我们使用了包含 500 棵树木和灌木的生物量数据集，涵盖了在巴西伯南布哥州的一项管理计划中采伐的 15 个物种。我们寻求开发本地模型并将它们与传统上应用于干燥森林的方程式进行比较——显示树高测量的重要性。由于与树的自变量的非线性关系，我们在调整模型时使用了非线性最小二乘建模技术，我们采用了交叉验证程序。总之，我们的地上生物量数据集最好用 Schumacher-Hall 方程表示：exp [3.5336 + 1. 9126 × log (D) + 1.2438 × log (Ht)]，这表明高度测量对于准确估计生物量至关重要。在我们的数据中测试泛热带模型时观察到的最大预测误差证明了开发新的本地模型的重要性，并表明如果计划在巴西的干旱森林中应用没有高度测量的通用“泛热带”模型，则应仔细考虑.