Cropland versus Gariga schrubland on soil organich carbon storage under Mediterranen climatic of Sicily

Soil organic carbon (SOC) pool is the largest among the terrestrial pool and it plays a key role to mitigate climatechange. The restoration of SOC pool represents a potential sink for atmospheric CO2. Land use is one of the mostimportant factors controlling organic carbon content. The main land uses throughout the Mediterranean are croplands(olive, wheat and vineyards) and scrublands. The land abandonment or the reclamation of land is changingthe cover of scrubland and cropland. This will change the carbon cycle. The aim of this work is determining thedirection and magnitude of soil organic change associated with land use change under Mediterranean ClimaticConditions. Using both historic record and land cover crop maps we estimated the effect of land cover changeon the stock carbon from 1972 to 2008 in Sicily. A system of paired plots was established on Mollic Gypsiriccambisol and Gypsiric cambisol on agriculture and rangeland land uses. The study sites were selected at thenatural reserve “Grotta di S. Ninfa”, in the West of Sicily. Soil samples (24) were taken at 20 and 40 cm depth,air dried and sieved at 2 mm. Dry aggregate size fractions selected were >1000 m, 1000-500 m, 500-250 m,250-63 m, 63-25 m and <25 m. The results show that gariga increase the organic matter in soil, mainly on theorganic horizon.