利用农业土壤固定有机碳——缓解全球变暖与提高土壤生产力

大气CO

Carbon Sequestration in Farming Land Soils: an Approach to Buffer the Global Warming and to Improve Soil Productivity

Global warming associated with arising of atmospheric CO2 is one the most challenging issues today. Agricultural soils behave either a source or a sink of the atmospheric CO2. Based upon the results of soil organic carbon increasing under conservation management, such as reduced- and no-till practice, rotation, and introducing cover crops in many long-term experimental in North America, soil scientists in USA and Canada believe that arable lands here have been changing from the source to the sink of atmospheric CO2. They further believe that carbon sequestrated in North America soils during next 20 years can reach 1.1 billion tons, accounting for 15% of total commission (in year 2008 ~ 2012) of both countries for CO2 emission reduction in the Kyoto Protocol. Hence, soil scientists and related governmental organizations are struggling to introduce the concept of carbon sequestration in soils to the negotiating table of global warming debate. The potential of soil sequestrating carbon is bigger in China than in North America. Management practices, such as conservation tillage, rotation, and cover cropping, widely adopted in North America would not only benefit our degrading soils, but also strengthen China's position in the future global warming negotiation.