GLOWCAD: A global database of woody tissue carbon concentrations/fractions

Woody tissue carbon (C) concentration is a key wood trait necessary for accurately estimating forest C stocks and fluxes, which also varies widely across species and biomes. However, coarse approximations of woody tissue C (e.g., 50%) remain commonplace in forest C estimation and reporting protocols, despite leading to substantial errors in forest C estimates. Here, we describe the Global Woody Tissue Carbon Concentration Database (GLOWCAD): a database containing 3,676 individual records of woody tissue C concentrations from 864 tree species. Woody tissue C concentration data—i.e., the mass of C per unit dry mass—were obtained from live and dead woody tissues from 130 peer-reviewed sources published between 1980-2020. Auxiliary data for each observation include tissue type, as well as decay class and size characteristics for dead wood. In GLOWCAD, 1,242 data points are associated with geographic coordinates, and are therefore presented alongside 46 standardized bioclimatic variables extracted from climate databases. GLOWCAD represents the largest available woody tissue C concentration database, and informs studies on forest C estimation, as well as analyses evaluating the extent, causes, and consequences of inter- and intraspecific variation in wood chemical traits.

木质组织碳浓度（Woody Tissue Carbon Concentration）是精准估算森林碳库与碳通量的关键木质性状，且该性状在不同物种和生物群区间存在广泛变异。然而，在森林碳估算与报告规程中，直接采用固定值（例如50%）作为木质组织碳浓度近似值的做法仍十分普遍，尽管此类操作会导致森林碳估算结果产生显著误差。本研究构建了全球木质组织碳浓度数据库（Global Woody Tissue Carbon Concentration Database, GLOWCAD），该库收录了来自864个树种的3676条木质组织碳浓度独立观测记录。木质组织碳浓度数据（即单位干质量中的碳质量）取自1980年至2020年间发表的130篇同行评议文献中的活体与枯死木质组织样本。每条观测记录附带的辅助数据包括组织类型，以及枯死木质组织的腐朽等级与尺寸特征。该数据库中共有1242条数据附带地理坐标，因此同步提供了从气候数据库中提取的46项标准化生物气候变量。GLOWCAD是目前已公开的规模最大的木质组织碳浓度数据库，可为森林碳估算相关研究，以及解析木材化学性状种间与种内变异的程度、成因及影响的各类分析提供数据支撑。