Estimating soil organic carbon sequestration change with applying modified Rothamsted Carbon model to paddy and upland fields in Japan

Abstract

Sustainability of the soil organic carbon (SOC) sequestration of farms producing the cereals which are raw materials of the biomass ethanol is an important issue. We estimated SOC sequestration change of a paddy field soil (Anthrosols) and an upland field soil (Andosols) in Japan with applying the modified RothC models, and suggested appropriate farming management for sustainable agriculture on the basis of SOC sequestration. In the paddy field experimental plots, at forage rice of Tachisugata plots, compost application of 0.5 - 1.2 Mg ha^-1 each year was required to maintain SOC content. In contrast, only plant residues in forage rice of Leaf star plots were sufficient to maintain SOC sequestration. In the upland field experimental plots, considering from the prediction, 2 Mg ha^-1 compost applications each year at the tillage and chemical fertilizer application plot is sufficient for maintain SOC content. Furthermore, plant residue was vital source of organic matter for chemical fertilizer plot, and SOC content would decrease 14.0 Mg-C ha^-1 from 2007 to 2030 if plant residue is carried out from the field. SOC sequestration under diverse assumed management conditions in Japanese fields is predicted. The modeling tool of RothC would be useful to field management for sustainable agriculture, so it is necessary to consider about the field management with using these modeling tools.