Carbon 200 Carbon dioxide 193 China 91 Organic carbon 74 Article 72 Climate change 72 Ecosystems 67 Biomass 61 Forestry 59 carbon dioxide 59 Greenhouse gases 56 Soils 54 climate change 52 carbon emission 50 Global warming 48 Sustainable development 46 human 45 carbon 43 controlled study 42 Gas emissions 39 biomass 38 nonhuman 38 Carbon emissions 37 Economic and social effects 36 Emission control 36 Energy utilization 36 Life cycle 36 Humans 33 carbon sequestration 33 metabolism 33