Measuring biomass and carbon stock in resprouting woody plants

Resprouting multi-stemmed woody plants form an important component of the woody vegetation in many ecosystems, but a clear methodology for reliable measurement of their size and quick, non-destructive estimation of their woody biomass and carbon stock is lacking. Our goal was to find a minimum number of sprouts, i.e., the most easily obtainable, and sprout parameters that should be measured for accurate sprout biomass and carbon stock estimates. Using data for 5 common temperate woody species, we modelled carbon stock and sprout biomass as a function of an increasing number of sprouts in an interaction with different sprout parameters. The mean basal diameter of only two to five of the thickest sprouts and the basal diameter and DBH of the thickest sprouts per stump proved to be accurate estimators for the total sprout biomass of the individual resprouters and the populations of resprouters, respectively. Carbon stock estimates were strongly correlated with biomass estimates, but relative carbon content varied among species. Our study demonstrated that the size of the resprouters can be easily measured, and their biomass and carbon stock estimated; therefore, resprouters can be simply incorporated into studies of woody vegetation.

萌枝型多茎木本植物是多数生态系统木本植被的关键组成部分，但当前仍缺乏可可靠测定其个体尺寸、且能快速无损估算其木质生物量与碳储量的清晰方法框架。本研究旨在确定需测量的最少枝条（即最易获取的枝条）数量及枝条参数，以实现对萌枝生物量与碳储量的精准估算。我们依托5种常见温带木本植物的实测数据，以萌枝数量与不同枝条参数的交互效应为自变量，构建了碳储量与萌枝生物量的预测模型。研究结果表明，仅选取2~5根最粗壮萌枝的平均基径，以及每桩株最粗壮萌枝的基径与胸径（DBH），即可分别精准估算单株萌枝植物的总萌枝生物量与种群总萌枝生物量。碳储量估算结果与生物量估算结果呈现极强的相关性，但不同物种的相对碳含量存在显著种间差异。本研究证实，萌枝植物的个体尺寸可便捷测定，其生物量与碳储量亦可快速估算；因此，萌枝植物可被简便地纳入木本植被相关研究范畴。