Mapping and modelling mass movements and gullies in mountainous areas using remote sensing and GIS techniques

Natural as well as human-induced mass movements and gullies are severe environmental hazards. Remote sensing data offer promising possibilities for identification and monitoring. But their effective use in mountainous areas is hampered by cloud effects and relief-controlled factors, which cause geometric distortions and shadow areas, among other constraints. Nevertheless, aerial photographs and satellite images (visible, infrared and microwave bands), or combinations thereof, have been successfully used to discriminate and delineate landslide and gully types. GIS modelling of mass movements and gullies, using ancillary information in combination with remote sensing data, is rapidly developing. The shortcomings of deterministic modelling of such chaotic phenomena as mass movements and gullies highlight the relevance of GIS-assisted approaches to exploratory and predictive modelling. This paper describes practical applications of remote sensing and GIS for mapping, monitoring, exploring cause-effect relationships and assessing hazards of mass movements and gullies in hilly and mountainous areas.