Developing allometric models to predict the individual aboveground biomass of shrubs worldwide

Aim Existing global models to predict standing woody biomass are based on trees characterized by a single principal stem, well-developed in height. However, their use in open woodlands and shrublands, characterized by multistemmed species with substantial crown development, generates a high level of uncertainty in biomass estimates. This limitation led us to i) develop global predictive models of shrub individual aboveground biomass based on simple allometric variables; ii) to compare the fit of these models with existing global biomass models; and iii) to assess whether models fit change when bioclimatic variables are considered. Location Global. Time period Present. Major taxa studied 118 species. Methods We compile a database of 3243 individuals across 49 sites distributed worldwide. Including basal diameter, height and crown diameter as predictor variables, we built potential models and compared their fit using generalized least squares. We used mixed effects models to determine if ...

目标 现有用于预测立木生物量的全球模型均基于具有单一主茎且高度发育良好的树木。然而，将其应用于以多茎物种为主、冠层发育旺盛的开阔林地和灌丛时，会导致生物量估算产生较高的不确定性。这一局限促使我们开展以下工作：i) 基于简单异速生长变量（allometric variables）构建灌木个体地上生物量的全球预测模型；ii) 将这些模型的拟合度与现有全球生物量模型进行比较；iii) 评估纳入生物气候变量时模型拟合度是否发生变化。
地点 全球。
时间范围 当前。
研究的主要类群 118种。
方法 我们汇编了一个包含全球49个站点3243个个体的数据库。将基径、高度和冠幅作为预测变量构建潜在模型，并使用广义最小二乘法比较其拟合度。我们采用混合效应模型以确定是否...