This study was conducted on the south slope of Al-Jabal Al-Akhdar (the Green Mountain) rangelands, northeast Libya to investigate changes in perennial plant species richness, landscape function and soil surface condition in order to determine whether exclosures are effected strategy for the improvement and rehabilitation of rangeland ecosystem at the regional level. Four study sites are positioned along a strong north-south rainfall gradient. A total of 28 monitoring sites were reinstalled and assessed between May and December 2014, the sites were then initially installed and assessed between the period of May and December 2006. The monitoring site layout is based on the Western Australia Rangeland Monitoring System (WARMS). The response variables measured were those included in the protocols of Landscape Function Analysis technique (LFA). Based on the results, LFA indices were in the low and medium scales in all of the monitoring sites within the exclosures. Notably, it is considered a good comparison tool for what it is currently occurring at the target grazing areas. No changes in perennial plant species richness amid the study areas, with the exception of the Thahar Altair area (TT). Overall, in estimation, at least 10 years of protection from grazing is required in the highest rainfall area (Maduar Zetun), and a considerably longer period in the lower rainfall areas to the south before vegetation cover and soil surface conditions recover sufficiently to be re-exposed to grazing. Consequently, grazing should be controlled to conserve national forage resources. تفاصيل المقالة

The degradation rate of Mediterranean steppes, especially in North Africa is 1% per year, and this considered a high rate of degradation. This study conducted in 2014 in the south slope of Al-Jabal Al-Akhdar, northeast Libya to quantify the vegetation recovery rate and assess selected Vegetation Indices (VIs) for mapping rangelands degradation status using remote sensing technology. Through a review of VIs we found that NDVI (Normalized Difference Vegetation Index) and MSAVI2 (Modified Soil Adjusted Vegetation Index) are the most useful indices for the study area to achieve the research objectives. Two Landsat (ETM+) satellite images (captured in September 2006 and 2014) used to map, monitor and assess the patterns of changes in plant cover. Three exclosures (fenced areas) with moderately to severely degraded soil and vegetation, were selected along a strong north-south rainfall gradient. Landscape Function Analysis (LFA) technique used to calculate Total Patch Area (TPA) for comparison purpose. According to the results, NDVI and MSAVI2 can be employed as a consistent and comparatively simple to use a tool in management and assessment of desertification processes in the Mediterranean rangelands. It seems that MSAVI2 more reliable than NDVI when the vegetation cover is very low. Overall, the plant cover did not change or increase for a large portion of regions at a time when 80% of the study area still under very severe and severe conditions of land degradation status. تفاصيل المقالة