Remote sensing and geographic information system (GIS) methods were used for karst research in the coastal area of Northwest Morocco near the city of Safi in order to identify karst landscapes, to describe karst features and to detect geological structures relevant to karst development. The aim of this study was to investigate the use of different satellite data, such as Landsat, RapidEye and IKONOS imagery, as well as ASTER-and SRTM-derived digital elevation models (DEMs) for the analysis of karst features. Dolines were identified by visual interpretations based on high resolution satellite imagery and aerial photographs. Digital image processing of the satellite data, such as deriving vegetation and water index images, helped to identify regions with relatively higher surface water input, where karstification processes might be more intense than in surrounding areas. ArcGIS-integrated weighted overlay tools were used for this purpose as well by aggregating of morphometric, causal factors (lowest and flattest areas) influencing the susceptibility to higher surface water input. Lineament analysis based on the different satellite data contributed to the detection of near-surface fault and fracture zones with potential influence on dissolution processes in sub-terrain waterways.

The quality , data amount and information content of GeoInformation Systems (GIS) dealing with natural hazards and vulnerability assessment has increased considerably during the last decades. Meanwhile many countries have implemented such a GIS for the public use, whereby satellite imageries before and after disasters form important layers within these GIS. In the scope of this research adaptation strategies are developed by presenting an approach in which Geographic Information Systems, used together with remote sensing data, contribute to the analysis and presentation of information, especially required for the increasing geo-hazards in Morocco, such as earthquakes, mass movements and flooding using mainly free available, existing data for contributing to a GIS integrated data base.

<p><strong>Abstract.</strong> Landslide hazard is one of the major environmental hazards in the coastal area. For helping the planners in selection of suitable locations to implement development projects, a landslide hazard zonation map has been produced for the coastal area of Safi (Morocco) as part of coastal Meseta. For this purpose, after preparation of a landslide inventory of the study area, some major parameters were examined for integrated analysis of landslide hazard in the region. The analyses of parameters were done by geo-referencing and lateral model making, satellite imaging of the study area, and spatial analyses by using geographical information system (GIS). The produced factor maps were weighted with analytic hierarchy process (AHP) method and then classified. The study area was classified into four classes of relative landslide hazards: negligible, low, moderate, and high. The final produced map for landslide hazard zonation in coastal area revealed that: the parameters of slope, geologic formation and fracturation have strong correlation and predict 75% of existing instabilities.</p>

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