Is Jordan suffers from desertification? view the map.
Most of Jordan arid and semi-arid areas has suffered
desertification. Although the rate of desertification was not identified, however several surveys and studies at the country's level indicated that Jordan's land is at the threat of high rate of desertification. The process has been accelerated by unsupervised management and land use practices of overgrazing, cultivation and plowing of marginal soils and woodland removal in the high rainfall zones. The regions of irrigated highlands and the Jordan Valley were also affected by aspects of salinization and alkalinization of soil. In addition to human induced factors, climatic factors of irrational rainfall and periodic droughts are contributing to the problem. According to Al-Hadidi (1996), the transition zone (between arid areas in the east and sub-humid areas in the west) has suffered from a high risk of desertification and is expected to lose its productivity over time.
Status of desertification
Desertification status in Jordan was investigated and tackled by few studies at the country level. In terms of desertification status, the country can be divided into four major zones as following:
I – Zone 1:
Includes the bioclimatic subdivisions of 7, 8 and 9 (Figure below) and mainly restricted to the Saharo-Arabian and Sudanian Penetration areas. Land regions 2, 5, 6, 7, 12, 13, 16, 17 and eastern parts of 14 are entirely within this zone. The area witnessed high rates of desertification and reached an advanced stage of desertification and can be considered as highly desertified area. Aspects of desertification in this zone are the absence of vegetation cover, the dominant desert pavements, the high salt contents and dominance of gypsiorthids soils. The desertification process within this zone is also accelerated by the low annual rainfall (<100 mm). At the eastern borders with Saudi Arabia, large areas are covered by sand dunes, particularly areas of Wadi Rum, Ghadeer al-Sheikh, Bayer and Mudawwara.The rest of the area is covered with desert pavement almost with no visible plant cover. Some plant species, however, can be found inside waterways.
II- Zone 2:
Most of this zone is Steppe and located within the Irano-Turanian climate.The area includes bioclimatic subdivisions 2, 3, 4 and 5 and land regions 11 and 15. The area is considered as a transitional zone of the Badia. Aprevious project (JAZPP, 2000) indicated that the intensive agricultural activity of barley cultivation and irrigation is taking place in the area. The dominant aspects of desertification in this zone are the higher rates of erosion by wind and water, the substantial accumulation of calcareous silt on the soil surface, low germination rate of plants, low intensity of plant cover caused by overgrazing and poor rainfall distribution. The area is also affected by soil surface crust that accelerates erosion by water and a soil compaction problem caused by uncontrolled movement and travel of grazing herds and vehicles. Many parts of this zone, however, have a high resilience; indicated by the high recovery and productivity of the protected natural vegetation inside natural and range reserves
III – Zone 3:
This zone falls completely within Mediterranean climate and includes semiarid and dry sub-humid zones (climatic subdivisions 1, 2 and 3) and the land regions of 8, 9 and 18. Annual rainfall in this zone is relatively high and varies from 300 mm to more than 600 mm. Existing soils are believed to be developed under humid climate which indicates that this zone has passed through a physical environmental change. Nevertheless, anthropogenic factors of woodland cutting, urbanization and land fragmentation have accelerated desertification in this zone. Currently, observed aspects of desertification includes the recession of forest areas, high rate of water erosion by water, expansion of urbanized area in the high rainfall zone, reduction in soil organic matter and soil compaction an deterioration.
IV – Zone 4:
This zone includes the irrigated area in Jordan Valley and extends from Tiberia Lake in the north to the Dead Sea in the south. The area is different from other zones in terms of climate, soils and land management. Irrigation is the dominant land use in this zone with surface water as the main source of irrigation. Aspects of desertification in this zone are mainly the soil salinization caused by improper irrigation practices and fertilization and land abandonment in the southern areas resulted from deep plowing and mixing of underlying Marl with soil material.Generally, the whole process of desertification in these zones is accelerated by the socio-economic factors of low income, inadequate inputs, improper management and overgrazing of natural vegetation
Causes of desertification
Generally speaking, land mismanagement and climatic factors of drought and climate change are the main causes of desertification in Jordan. Several practices are aggravating degradation in the first and the second zones. The irrational plowing, the cultivation of land for barley, the mismanagement of plant residues and the overgrazing of natural vegetation are the main causes of desertification in these zones. Causes of desertification in the third zone include forest cutting, inappropriate land use, random urbanization, land fragmentation and over-pumping of groundwater. In the fourth zone, land degradation aspects and causes are mainly attributed to mismanagement of irrigated lands, particularly in the middle and southern parts of Jordan Valley. In addition to the above causes of desertification, a very important factor of desertification in the country is the high population growth which exerts more pressure on the natural resources to meet the demands of the increasingly growing population.
Ministry of Environment - Jordan
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