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Al Jabal al Akhdar, Locally known as the Green Mountain, located in Cyrenaica on the north east coast of Libya. It is a limestone plateau with maximum altitudes of about 900 meters, holds the highest plant density and species diversity within the country. Among these plants is the Juniperus phoenicea (JP) which covers about 70% of this mountain. It has been sharply deteriorated by unidentified causes over large scales. In this work, we have used remote sensing and GIS data to monitor vegetation vigor variations and study the drought related issues to forest and JP decline in the this area. The analysis of the collected data involved Topological, Geological and Geographical (TGG) data modelling over the selected area and within a period of eight years from 2006 to 2013. We have included two main data sets among few sets of satellite images that were employed in this study. The first data set was from the updated version of Shuttle Radar Topography Mission (SRTM) DEM of ~90 m spatial resolution and the second data set from Landsat 7 and Landsat 8 Level 1T images of 30 m spatial resolution. The collected data were used to construct the images and figures, to monitor and map the forest and JP decline through the normalized difference vegetation index (NDVI) and, then to illustrate the expected reasons and attributes for this decline. The study attributes the decline due to several specific indicators related to TGG inter-related factors including; altitude, slope, aspect, drainage pattern, topographic curvature, seawater intrusion, wind and soil erosions. The results were consistent and in a good agreement with several published data on the effect of topography, geology and geography on vegetation covers of similar terrain regions.

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From the beginning of the twentieth century, topographic maps for the Libyan state carried out by various compilers, where the first mapping was carried out by the Italian Military Geographical Institute, the Soviet Union Military, and the U.S. Army, followed by mapping carried out by the Libyan state from the 1950s to the 2000s. Most of these maps have not been digitized and updated using the techniques of geographic information systems and remote sensing. This paper discusses on the objectives, methodology and results of the Libya Topography Project, “Libya Topo” for updating the previously compiled topographical map at scale, 1:250000. Open spatial data from different platforms (OSM, Logistics Cluster, Landsat 8 satellite imagery, and SRTM data, etc.). Also, POIs extracted from previously compiled topographic and geological maps. Spatial database for each UTM zone created to store the features and raster. As for the cartographic style, the map layout adopted is the style of the U.S. Defense Mapping Agency maps. The results of the project are an update of 121 topographical map sheets using Quantum (GIS), those will be freely available for the interested users on request (e.g., environmentalists, academics, and university students, etc.).