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Item type: المادة , Study and assessment of natural vegetation cover in the Jabal Al-Akhdar region (Final report)(Omar Al-Mukhtar University, 2005) Omar Al-Mukhtar UniversityThis exploratory study was initiated to assess the condition of shrub vegetation in the Jabal al-Akhdar region and to identify the causes of the deterioration that had become clearly evident in one of its most important components: long-lived evergreen juniper trees, which account for an estimated 80% of all mature trees in this important region of the Great Jamahiriya. The specialists who conducted the study considered it necessary to include natural rangelands, recognizing that the conservation and development of shrub cover can only be achieved by characterizing the vegetation of natural rangelands, identifying their ecological assets, and proposing measures for their improvement. Such measures would help reduce the pressures exerted on forest and scrubland areas by increasing numbers of livestock that roam through them in search of forage sufficient to meet their nutritional needs. The study was also undertaken to establish a scientific perspective grounded in factual evidence and quantitative measurements, with the aim of addressing the questions and interpretations circulated at all levels concerning the observed deterioration in the condition of natural vegetation across Jabal al-Akhdar. The following section presents the preliminary indications reached by the specialists through an exploratory investigation of a natural phenomenon whose occurrence involves complex interactions among biotic and abiotic factors. More detailed studies are required to determine the role of each factor. Because the characteristics of complex ecosystems change only over long time scales, it is difficult to establish the causes of their degradation within a period of no more than eighteen months, which was the duration of the present study. It is well established that a number of indicators are used to assess the condition of shrub and rangeland vegetation in a given area. Some have been proposed by major international agencies, such as the Food and Agriculture Organization of the United Nations (FAO) and the United Nations Environmental Protection Agency (UNEPA), while others have been adopted by international and regional organizations, including the International Union for Conservation of Nature (IUCN) and the World Wide Fund for Nature (WWF), which is concerned with Mediterranean forests. These indicators include measurements of growth rates, vigour, density, canopy cover, regenerative capacity, and the level of services available to people, such as recreation in the surrounding environment and the utilization of vegetation products. Natural vegetation may also be assessed according to its capacity to provide suitable conditions for wildlife and economically important insects, such as honey bees, and to protect soil against erosion, thereby slowing the acceleration of desertification and sand encroachment onto agricultural land and human settlements, particularly in arid and semi-arid regions. Modern technologies, including satellite imagery, are also used to document the total area occupied by natural vegetation across a defined tract of land at a particular historical point, in order to monitor subsequent changes in its extent or condition and to investigate their causes. Guided by these considerations, plans and implementation mechanisms for the study and assessment of natural vegetation in Jabal al-Akhdar were designed to address these vital aspects and ensure the achievement of the study objectives. This is reflected in the reports produced by the specialized working teams and in the resulting important database covering geology and mapping, soils and water resources, forests and rangelands, diseases and pests, and the socioeconomic characteristics of the region's population. On the basis of the field and laboratory observations and data obtained by these teams, documented in periodic reports throughout the exploratory study and compiled in this final report, marked deterioration in shrub and rangeland vegetation, together with a reduction in its extent, was recorded in several areas of Jabal al-Akhdar. Indicators of the deterioration of natural shrub cover - although varying in their manifestations and severity - were not confined to a single area. Degradation was recorded at several locations on the first coastal terrace, including Sidi Amer-al-Hamamah, Wadi al-Jabal, and Wadi Bualnidi; on the second terrace, including al-Sultiyah, Qandafurah, and Silyun; and on the third terrace, including Qasr Libya-Marawah, Wadi al-Mafwah, and Wadi al-Sudan. The results showed that the diseases and pests recorded in the Jabal al-Akhdar areas targeted by this exploratory study are common in such environments. These included spotting diseases affecting al-Sakhab, al-Butum, and al-Barish; soil fungi recorded on al-Zuhayrah and al-Shabraq; cicadas (Bourzin); and weevils. At this exploratory level, however, these organisms were not found to constitute a principal cause of the degradation affecting shrub cover in particular. Dense lichen growth on juniper trees in some severely degraded areas has attracted the attention of many observers and may lead them mistakenly to assume that the lichens caused tree mortality. In fact, these growths are opportunistic organisms that found a suitable habitat on trees after the trees had already undergone decline or complete death as a result of other, non-pathogenic factors. The indicators of natural vegetation condition used in this study, including density, canopy cover, and regeneration, also showed that, despite the death of substantial numbers of juniper trees or parts of them, appreciable regeneration of the dominant tree and shrub species was recorded across the region. This was evident in the numbers of juniper seedlings along paved road verges and beyond, including at Qasr Libya-Marawah, Mirad Masoud, al-Aslab, and the coastal zone extending from Soussa to al-Hamamah. Resprouting of al-Shammari and al-Butum shrubs was also observed at sites from which they had been removed or where they had been destroyed by severe fires, including Talaq Nazar, Ras al-Hilal, and Sidi Hamad. In addition, terraces currently occupied by invasive trees, as in Mirad Masoud and al-Bayadah, are expected to recover their formerly dominant shrub cover - which was cleared in the 1980s for the cultivation of fruit trees - provided that seed sources are available and the soils are protected against erosion. These signs merit close attention and should be monitored, while suitable conditions should be created to extend their occurrence throughout Jabal al-Akhdar. Moreover, important sites such as Mirad Masoud-coast, Sidi Khalid, Ras al-Turab, and al-Zardah have retained the vigour, density, and diversity of their natural shrub cover, either because they were not exposed to indiscriminate fires or excessive cutting, or because favourable soil conditions were present, particularly adequate soil-profile depth and available moisture. Other contributing factors include fissures, fractures, and cavities resulting from tectonic movements, which are penetrated by tree and shrub roots and allow the retention of soil produced by weathering and leaching processes, thereby providing a degree of moisture and nutrients. Such conditions have been documented on the slopes surrounding the channels of Wadi al-Kuf and Wadi al-Sudan and on the hills extending from al-Hamamah to Sidi Amer, which are characterized by dense and diverse shrub cover. The study further showed that the areas occupied by natural forests and scrublands have declined in comparison with their extent in the early 1970s. An earlier report submitted by FAO indicated an area of approximately 320,000 hectares, whereas the present study estimates the current area at only about 299,000 hectares. This reduction is partly attributable to major agricultural development schemes under which important agricultural settlement projects were established on land excised from natural forests, as occurred in al-Wasitah, al-Marj, Farzu'ah, al-Bayadah, Mirad Masoud, and elsewhere. The sites selected at that time for these agricultural projects, as well as the areas allocated to them, were appropriate to the characteristics of the respective regions and demonstrated strong consistency with the principles of optimal land use and sustainable development. These principles enable productive land to be used for crop and fruit-tree cultivation while conserving natural vegetation in other areas that do not meet the criteria for such investment. However, the unsustainable human activities that followed and continue to the present - including the indiscriminate removal or deliberate burning of shrub cover to cultivate marginal crops or fruit trees, or to provide grazing land on shallow or rocky soils - have contributed both to the contraction of natural forests in these areas and to the spread of low-value invasive plants in their place. Accordingly, the quality and area criteria recommended by specialized international institutions and adopted as benchmarks in this exploratory study for assessing the condition of natural vegetation indicate degradation in some major components of shrub vegetation in Jabal al-Akhdar, including juniper and al-Shammari. The onset of this degradation cannot be attributed directly to drought resulting from reduced rainfall or poor rainfall distribution. Soils throughout Jabal al-Akhdar, across their different classifications, including those that supported well-developed shrub cover, had low moisture contents, and their capacity to provide moisture did not differ substantially from that of soils in areas characterized by severely degraded shrub cover. The study further indicates that, although the pests and diseases prevalent in these areas have important effects on natural vegetation, their severity is not sufficient to account for the level and intensity of degradation observed in several parts of Jabal al-Akhdar. Negative human practices, particularly indiscriminate cutting and overgrazing in sensitive environments such as mountain slopes and rangelands, constitute the most serious threat to ecosystems in general. The continued acceleration of both qualitative and quantitative degradation may ultimately lead to the loss of a national natural resource that would be difficult to replace. The study confirmed that the natural rangelands south of Jabal al-Akhdar are in a very poor condition as a result of the degradation of their natural vegetation. Indicators of degradation in these areas include the local disappearance of several annual plants and short evergreen shrubs, severe declines in their density and vigour, the spread of plants of low forage and economic value, or a combination of these conditions. Given the characteristics of the southern areas, which contain extensive and important rangelands such as Buzra', al-Nazur, al-Mukhayli, Jardas, Sidi Saad, and al-Habshah, and which are characterized by higher mean temperatures, degraded soil properties, lower rainfall, and poor rainfall distribution, the continuation of prevailing grazing practices will have serious consequences. Of particular concern are the increase in livestock numbers to unrealistic levels and the failure to allow sufficient time for the remaining adapted native plants of relatively good forage value - such as al-Ramth, al-Qurtah, al-Hajram, and wormwood - to reproduce and regenerate naturally through appropriate rotational grazing systems. Continuation of these practices will diminish the importance of this rangeland vegetation and intensify desertification in these important parts of Jabal al-Akhdar. The deterioration of soil properties following the removal of mature trees by people - especially on steep slopes - and the destruction of old check dams, both characteristic of forest and scrubland areas in Jabal al-Akhdar, has stimulated other destructive processes, including soil erosion and the loss of soil fertility. Deliberately set fires, which have now become common in the forests of Jabal al-Akhdar and which destroy natural vegetation, provide the clearest illustration of the adverse role played by people in relation to ecosystems. In addition to destroying enormous numbers of trees and shrubs - especially juniper trees that formerly covered steep hills across vast areas including Ras al-Hilal, Talaq Nazar, Sidi Hamad, Sidi Amer, Wadi Marqus, and elsewhere - severe fires have also destroyed signs of natural regeneration and created opportunities for other low-value invasive species to become dominant. Overgrazing in these areas has likewise reduced the effectiveness of soil-development processes by compacting the soil, lowering the rate of water infiltration through the soil layers, and reducing the accumulation of organic matter. These effects have adversely affected vegetation and prevented the establishment of new seedlings, either because their growing environment has deteriorated or because livestock feed on them. Such effects are clearly visible in areas where grazing is intensive, and juniper in particular has failed to regenerate naturally in locations where it was formerly dominant. The reduced growth and vigour of shrub vegetation, which frequently accompany these negative human activities, have made plants more susceptible to diseases and pests, impaired their ability to grow and reproduce, and reduced their capacity to benefit from the distinctive environmental resources of the region, which remain capable of supporting significant vegetation cover. Despite the challenges it faces, the natural vegetation of Jabal al-Akhdar continues to represent a model of a unique ecosystem extending along an important part of the southern Mediterranean coast. This exploratory study documented and highlighted its natural assets, and its findings confirmed the diversity and distinctive character of the region's climate, landforms, soils, water resources, shrub cover, natural rangelands, and medicinal and aromatic plants. The study also emphasized its long-established social systems and human cultural heritage, which demonstrate the region's historical contribution to shaping the legacy of the past and its continuing efforts to sustain this vital ecological and human role in the present and the future.