A Multidisciplinary GIS-Based Approach for Mapping Paleoriver Migration: A Case Study of the Serchio River (Lucca Alluvial Plain, Tuscany)

Abstract

This paper presents a multidisciplinary study of river migration in alluvial plains. The selected case study is a sector of the Lucca alluvial plain (Tuscany, Central Italy) in which the Serchio River flows. Various types of data were collected, analyzed, and processed using a GIS. In particular, remote sensing imagery of different resolution (aerial orthophotos and satellite images) were processed to enhance buried fluvial features. Detected features were compared with data from stratigraphic investigations, archaeological surveys, geomorphological maps, and previous remote sensing studies. Traces of ancient channels were mapped and compiled in an interactive vector database listing the most important characteristics of each element. Two fluvial channel systems (here called primary and secondary) of differing size (e.g. length and width) were identified. Our analyses confirm the major features of the main paleochannels identified in previous works and enabled the discovery of smaller channels thanks to the higher resolution of the source data. These new traces suggest the existence of a secondary drainage network comprising minor channels of the Serchio River modified by human activity. These secondary paleotraces are possibly linked to channelling for land reclamation purposes beginning in the Roman period, when the alluvial plain was reorganized on the lines of Roman centuriation.