Table 2: The baseline SOC stocks of major land use classes and their change rates.

Land use typeNumber of pixelaChange in pixelSOC in 19721972–1998bSOC in 19981998–2007
1972199820071998–2007Mg C/haMg C/ha/yr Mg C/haMg C/ha/yr

Forest2752372976074.0−0.2275.0−0.02
Grassland734466184865−175381.9−0.1176.10.04
Agriculture263272434222705−163786.6−0.4575.90.05
Wetland183616843309162595.9−0.3875.60.04

Mean85.8−0.3875.90.04
Stdev22.90.2719.70.40

aPixel size =  m2.
bBaseline SOC stocks in 1998 for each land use type are not necessarily associated with the calculation of annual SOC change rate for 1972–1998 because of land use change.