Estimating and mapping of soil carbon stock using satellite data

Abstract:

Recently, the carbon capture and storage has been attracting attention as a method for the mitigation of the global warming in agricultural sphere. In Japan, since its topography is complicated, precision monitoring and investigation has a limit. So, utilization of the remote sensing is expected as a precise and effective investigation method. Previous research in Japan, Sekiya et al. (2010) estimated the soil carbon stock from soil surface down to 100 cm depth in Hokkaido. However, the estimated values may not reflect current situation, because in this research relatively old soil survey data from the 1960’s to the 1970’s were used to estimate the soil carbon stock.

Under this background, we developed an estimation method using satellite data to evaluate the soil carbon stocks in the agricultural field covering wide area to be used as the fundamental data.

Result of our study suggests that there is a significant correlation between the amount of soil carbon and the reflectance value from visible to near-infrared wavelength region. This is the reason that the color of the soil becomes dark and electromagnetic wave absorbency from visible to near-infrared wavelength increases corresponding with increment of the soil carbon content. Especially, a high negative correlation is found between the reflectance value of red wavelength and the soil carbon stock in the SPOT satellite data of 2013.