organic carbon Organic carbon 15 Soils 9 China 8 soil carbon 6 Ecosystems 4 Forestry 4 Soil organic carbon 4 carbon sequestration 4 Sediments 3 Soil organic carbon sequestration 3 Vegetation 3 Algae 2 Biomass 2 Carbon sequestration 2 Climate change 2 Digital storage 2 Ecology 2 Lakes 2 Land use 2 Landforms 2 Microorganisms 2 Nitrogen 2 Organics 2 Soil carbon sequestration 2 Wetlands 2 bioenergy 2 biomass 2 glacial-interglacial cycle 2 grassland 2