Carbon sequestration and soil organic carbon
The 10 cropping systems received different amounts of carbon input in the form of crop residues, manures and cover crops (Figure 1). The organic corn/tomato rotation (OMT) received the most carbon inputs and the unfertilized, rainfed wheat/fallow (RWC) received the least.
Carbon inputs to the 10 cropping systems (Kong et al., 2005).
Changes in the average amount of carbon accumulated or lost over the ten-year period from 1994 to 2003 are represented in Figure 2 for all the cropping systems. The OMT system had the largest increase in soil organic carbon (SOC). The RWC system showed a decline in SOC while SOC in the other wheat systems was not significantly different. This information is important for assessing the potential for carbon sequestration in California soils.
Rate of soil organic sequestration (Kong et al, 2005).