Soil carbon stock changes due to afforestation in Japan by the paired sampling method on an equivalent mass basis

To identify the soil carbon stock changes from croplands/grasslands to forestlands in Japan, we compared of a cropland/grassland with that an adjacent forestland at 22 different sites. With respect 0–30-cm depth basis, was same as forestland; however, it less than when equivalent mass approach used. The ratio 1.11 on average, which is comparable previous mass-corrected paired sampling studies. affected by two factors: tree age and current vegetation. Mean annual temperature, mean precipitation, phosphate absorption coefficient, litter quantity, former land use did not affect ratio. According comparison results study for deforestation, application reciprocal deforestation afforestation slightly overestimated. Further studies are necessary establish general conclusion. Some studies, including those involving non-mass-corrected data, possibly biased, more using method basis must be conducted provide factor change future.