Capability of sands spectroscopy in sediment dispersal study along the Tuscan Coast (Italy)

One of the most important factors controlling the dynamics of coastal areas is river input of freshwater and its sediment load. Spatial variations in lithology provides information on the direction of sediment transport patterns, which can be studied through conventional analysis. Reflectance properties of sediments are related to lithologic composition and grain size. These properties can be investigated using hyperspectral and multispectral techniques to detect possible changes of their distribution in time and space and to produce maps at different scales. Compared with conventional petrographic and granulometric analyses, which are generally invasive, timeconsuming and expensive, remote sensing techniques allow a rapid acquisition of a large amount of data on sediment properties, such as lithologic composition and grain size. The study area is located in Tuscany between the mouth of the Serchio river and the harbor of Livorno. Along this sector three river mouths (Serchio, Arno and Scolmatore) discharge their sediment load affecting the composition of the littoral sands. About 130 sediment samples have been collected along the coast in the study area. Sampling site were situated along beaches at several depths (from +1 to - 5 m), in different locations within the Holocene and Upper Pleistocene coastal dunes and in the river beds of the three water courses. The lithological composition of the collected sand samples, based on petrographic microscopy analysis, have been compared to the spectral response obtained using the Analytical Spectral Device (ASD) Fieldspec spectroradiometer, in order to investigate the relation between such features.