Tuesday, November 3, 2009
Convention Center, Exhibit Hall BC, Second Floor
Sugarbeet production can potentially sequester carbon (C) in the following intermediate- and long-term pools: soil organic matter, soil inorganic matter, and the sugar product. Reducing fossil fuel combustion and slowing organic matter decomposition rates will also curtail the rate of atmospheric CO2 concentration increase. The purpose of this work was to identify and quantify potential C credits resulting from sugarbeet production that can offset C emissions from sugar factories. Management practices considered as variables in this project were tillage, lime application, and cover crop production. Estimates of C emission to the atmosphere and C addition to the soil resulting from sugarbeet production were based on data from peer-reviewed sources and records from sugar cooperatives. Carbon emissions from the following sources were included in the C audit: soil respiration, CO2 off-gassed following tillage, fertilizer and lime production, and operations related to tillage, fertilization, and lime application. Carbon contained in the harvested biomass of an average sugarbeet root crop is 6.3 Mg C ha-1. Potentially sequestered C in a conventional tillage system without cover crop production or lime application is estimated to be 4.8 Mg C ha-1 yr-1; this value includes the C in the harvested root biomass. The greatest value for potentially sequestered C was attained with strip tillage and lime application; the estimated value is 5.2 Mg C ha-1yr-1, including harvested root biomass.