“The European Space Agency is organising the first “Sentinel-2 Preparatory Symposium”, which will be hosted in ESA-ESRIN, Frascati, Italy, from 23 to 27 April 2012.”
In context of Land use and Cover change (LUCC), we will present a poster on “Estimation of carbon capture and storage from LUCC. We compute land use change maps in the southwest of Toulouse (France), from satellite classifications during 2002 to 2010. This study was conducted in two parts: (a) changes in land use between 2002 and 2009; (b) crop rotations year by year. Tests are done on Formosat-2 images and in progress on Spot2-4-5 images.
The methodology consists in (1) classification to obtain land cover maps for each year (2); regrouping the main land cover theme in the classification result (Woodland, Water, Built up area / mineral surfaces, Grassland, Crops; (3) regularization (smoothing) the classified images by using segmentation; (4) contour erosion: to compare classified images, it is necessary to eliminate mixed pixels (pixels on border of two classes) which correspond to false changes and imply change errors in statistical results; (5) comparison of classified images from change matrices: change-classes are created; (6) Crop rotation: comparison of N classifications in N years and obtaining change matrices and change image; (7) the soil carbon stocks are estimated using a mathematical model (INRA, 2002) from statistics obtained by the land change map.
Land use change maps for the main classes (forest, croplands and pastures) are used to estimate Soil Organic Carbon (SOC) changes by applying a simple model based on regional observations (Soussana and Arrouays 2004). Crop rotation maps will be employed to refine this approach. Regional yield statistics will be computed to estimate Net Primary Production (NPP) and crop carbon balance by using a similar methodology as proposed by West et al. (2010).
