Soil Organic Carbon Stock

Soil organic carbon (SOC) is the carbon held within soil organic constituents (i.e., products produced as dead plants and animals decompose and the soil microbial biomass). Only SOC in the top 20-cm soil layer is estimated for this variable. Data of this variable were generated by the USGS LandCarbon project using the General Ensemble Biogeochemical Modeling System (GEMS) based on selected IPCC emissions scenarios, biogeochemical models, and climate datasets. The spatial extent is the conterminous United States and the temporal extent is from 1992 through 2050. These data are projected to Albers Equal Area in the NAD83 datum at a resolution of 2000 meters and are spatially gridded in GeoTiff format. Units of measure are expressed in g Carbon/m2土壤有机碳（Soil Organic Carbon，SOC）指储存于土壤有机组分中的碳，涵盖动植物残体腐解产物与土壤微生物生物量所含的碳。本数据集仅针对0~20厘米表层土层的土壤有机碳进行估算。该变量数据集由美国地质调查局（USGS）LandCarbon项目构建，基于筛选后的政府间气候变化专门委员会（IPCC）排放情景、生物地球化学模型与气候数据集，通过通用集合生物地球化学建模系统（General Ensemble Biogeochemical Modeling System，简称GEMS）生成。数据空间覆盖美国本土区域，时间跨度为1992年至2050年。所有数据均采用NAD83基准面的阿尔伯斯等面积投影（Albers Equal Area）进行投影，分辨率为2000米，并以GeoTiff格式实现空间网格化存储。计量单位为克碳/平方米（g C/m²）。