Global aboveground biomass carbon density of trees in the year 2010

This layer represents the aboveground biomass (AGB) carbon (C) density estimates for trees that were used to create the harmonized global AGB C density map of Spawn et al. (2020). It has been scaled by 10 to reduce file size and should by multiplied by 0.1 before analysis to attain units of megagrams C per hectare (MgC/ha). Since trees may coexist with other vegetation types within the extent of a given grid cell, estimates in this layer have been proportionally adjusted to account for the relative spatial extent that trees are assumed to occupy in each grid cell. Grid cells that do not contain trees report a value of zero. As such, taking the pixelwise sum of the accompanying layers for tree, grass, tundra and crop AGB C will produce the harmonized global AGB C density map of Spawn et al. (2020).本图层用于呈现用于构建Spawn等人2020年提出的协调统一全球地上生物量碳密度地图的树木地上生物量（Aboveground Biomass, AGB）碳（Carbon, C）密度估算结果。为压缩文件体积，本图层已进行10倍缩放，在分析前需将其乘以0.1，以得到单位为每公顷兆克碳（Megagrams C per hectare, MgC/ha）的真实数值。由于在给定网格单元的范围内，树木可能与其他植被类型伴生共存，本图层的估算值已按比例调整，以适配各网格单元中树木假定占据的相对空间范围。不含树木的网格单元像素值为0。据此，将本图层与树木、草本、苔原及作物的地上生物量碳配套图层进行逐像素求和，即可得到Spawn等人2020年的协调统一全球地上生物量碳密度地图。