Fine-Scale Spatial Variability of Soil Organic Carbon and Related Environmental Variables in a Protected Area of Sicily, Italy

Abstract

The institution of Natural Reserves has promoted, in Italy, the conservation and the environmental improvement of several areas and their physical and biological factors. Agriculture, forestry and every human activity are regulated to preserve their high ecological and naturalistic value. Land use, in particular, must follow careful rules to preserve the soil fertility and to limit the factors of landscape degradation. Maps of soil organic carbon (SOC) or soil organic matter (SOM) are of interest for agricultural management, resulting a very important soil fertility parameter, as well as in environmental policy related to the terrestrial sequestration of atmospheric carbon. Thus, a better understanding of the distribution of soil organic carbon (SOC) pool is necessary in order to manage soil fertility and to predict its potential responses to land use change. Geostatistics is widely used to map SOC at any scale level assessing also the statistical uncertainty. At fine scale level geostatistical methods that utilize spatially correlated secondary information increase the quality of the maps of SOC distribution (Simbahan, 2006). In fact, whereas are significant correlations between the target variable and secondary data hybrid techniques generally result in more accurate local prediction (Goovaerts, 1999; McBratney et al., 2000). The goals of this study were: i) to assess the SOC spatial variability in the Natural Reserve of S. Ninfa (Italy) and ii) to quantify the relationships among soil C, land use and some environmental variables.