Wind erosion is controlled by reducing the wind forces on erodible soil particles or by creating aggregates on soil surfaces that are? more resistant to wind forces. There are various methods of biological and physical methods to control wind erosion, including windbreakers, maintaining vegetation residues on the soil surface, utilizing stable soil aggregates or clods, reducing field width, roughing of the land surface and leveling of the land.
Much progress has been made in the evolution of technologies for the prevention and control of wind erosion in recent years. On the application side, however, there remains more to be done, especially in arid regions. A closer analysis of the wind erosion situation in these areas will indicate that if this phenomenon is to be controlled and contained, there is a need to first appraise and understand existing techniques, then to select and apply the most appropriate mix of technologies in the context of integrated land management specific to each region.
While individual conservation practices can be successful in controlling erosion, a combination of practices should always be considered when a wind erosion control system is being planned. Droughts will be always a limiting factor in planing of wind erosion control methods. Soil clods and ridging for erosion control are all temporary control measures and serve best as supplemental practices (1).
Climatical factors play important roles in wind erosion control. A dry and windy climate is essential in the process of land desertification. The climatical factors mainly include wind regime, precipitation, temperature, and humidity, among which wind speed is the primary factor because it is the most direct power source of soil erosion. The higher the wind speed is, the greater the erosion will be. Temperature and precipitation are also important factors affecting wind erosion. These two factors determine the drought degree of a region, and a drier soil is more feasible for wind erosion. Therefore, in evaluating the wind erosion potential of an area, climatical factors should be the first condition taken into account in the evaluation of the process (2).
As mentioned before, there are different methods to control wind erosion, including biological methods (using plants as windbreak and sand dune stabilizers) and mechanical methods (trench excavation and building windbreak). Soil surface layer reinforcement using soil stabilizers such as petroleum mulches and polymeric materials can also be implemented. Applications of mechanical and biological combinations are especially useful to reduce the execution time and costs of the surface stabilization. Principles for controlling wind erosion in farming areas include stabilizing them with various materials; producing a rough, cloddy surface; reducing effective field width with barriers; and establishing and maintaining sufficient vegetative cover (3).
Eucalyptus trees as windbreak
Those principles for controlling wind erosion are summarized by the general functional relationship given by Woodruff and Siddoway in 1965 as a wind erosion equation in the form E = f (I,K,C,L,V), where E is potential average annual soil loss per unit area, “I” is a soil erodibility index based on fraction of non-erodible soil aggregates (particles > 0.84 mm) in the erodible size range, “K” is a soil ridge roughness factor, “C” is a climatic factor, “L” is the unsheltered median travel distance of wind across a field and “V” is equivalent quantity of vegetative cover. The equation was developed as a result of many years of studying the factors influencing wind erosion. It has been used widely for its intended purposes to determine both the potential erosion from a particular field and the field conditions (soil cloddiness, roughness, vegetative cover, sheltering by barrier, or width and orientation of field) necessary to reduce potential erosion to a tolerable amount (4).
Field length according to WEQ and RWEQ
Wind erosion control is carried out on two fronts: reduction of wind-speed at ground level and an increase in soil cohesion, thus improving soil resistance to wind.
Increasing Soil Cohesion: Soil cohesion depends strongly on the consistence, packing, and saturation condition. Cohesion of soil is an important factor of soil consistency. The word cohesion, however, has acquired two connotations. In soil physics, it is defined, as the cohesive force that takes place between adjacent particles. In soil mechanics, however, cohesion means “the shear strength when the compressive stresses are equal to zero”. It is apparent that these two meanings differ. For the sake of convenience, “soil cohesion” will here refer to the soil physics definition, while “shear cohesion” will refer to that of soil mechanics. Theoretical concepts of soil cohesion is an ideal soil composed of uniform spherical particles and others on the basis of surface-tension force due to water films between particles (5).
Soil erodibility is not a static characteristic but rather one that varies with time. It is also a factor of soil cohesion, which in turn can be influenced by moisture content as well as the absorptive and electromagnetic forces that bind soil particles together, especially in clays and silt (6).
The sum integration of various physical, chemical and biological properties create soil productivity. This is often referred to as “soil quality.” Soil quality can be defined as an inherent attribute of a soil that is inferred from its specific characteristics and observations (e.g., compatibility, erodibility, and fertility). The term also refers to the soil’s structural integrity, which imparts resistance to erosion, and to the loss of plant nutrients and organic matter. Lack of soil quality is often related to soil degradation, which can be defined as the rate of change over time in soil quality.
In characterizing soil quality, biological properties have received less emphasis than chemical and physical properties, because their effects are more difficult to measure, predict, or quantify. Improved soil quality is indicated by increased infiltration or aeration, presence of micropores, aggregate size, aggregate stability, the organic matter content of soil, decreased bulk density, soil resistance to erosion, and nutrient runoff (7).
Soil organic matter (SOM) is the most important indicator of soil quality and productivity and consists of a complex and varied mixture of organic substances. Soil organic matter is commonly defined as the percentage of humus in a soil’s composition. Humus is the unidentifiable residue of plant soil micro-organisms and fauna that becomes fairly resistant to further decay. Organic matter is very important in the functioning of soil systems for many reasons. Soil organic matter increases soil porosity, thereby increasing infiltration and water-holding capacity of the soil, providing more water availability for plants and less potentially erosive runoff and agro-chemical contamination (8).
SOM is an important component of both managed and unmanaged terrestrial ecosystems and it is especially important in influencing soil erodibility. SOM contains three times more carbon than vegetation and twice the carbon content of the Earth’s atmosphere. Organic matter in eroded soil decomposes at a greater rate than in intact soil. Stable SOM (humus), which can have a mean residence time of centuries, becomes a potential source of “greenhouse gases” through a series of biochemical transformations initiated by the physical process of erosion. Erosion enhances SOM decomposition at two locations: the eroded surface of the land and the eroded ‘in transit’ soil / sediment. Erosion creates a new pool of mine- realizable organic matter that is different from the remaining stable organic matter. This transported soil organic fraction is no longer under the same physical and environmental conditions that allowed the organic matter to initially stabilize (9).
In places with enough water availability, supplementary irrigation can be an effective and financially viable way of reducing erosion problems. Irrigating the soil prior to the normal rainy season is sufficient to allow favorable tillage conditions and establish plant cover before the rainy season.
Increasing roughness of the soil surface: Smooth soil surfaces offer little resistance to the wind force. Keeping the surface rough by tilling when the soil is moist enough to form large clods will reduce wind erosion. It is also important to recognize that excessive and frequent tillage can gradually reduce roughness of soil by breaking clods and aggregates that resist erosion. Tilling dry soil may cause a dry dust to form, which can aggravate an erosion problem. Ridges and depressions formed by tillage alter wind speed by absorbing and deflecting part of the wind energy away from erodible soil. Effective ridges must be nearly perpendicular to the direction of prevailing winds. Rough surfaces also trap moving particles. This reduces abrasion and the normal build-up of eroding materials downwind (10).
Research shows that creating ridges 50-100mm high, at correct angles relative to the wind, reduces erosion. But erosion increases again if ridges exceed 100mm in height (11).
Surface roughness can also determine the erosion potential of fields. As fields become smoother, the potential wind speed at the soil surface becomes greater. Surface roughness is due to clods (random roughness) and tillage ridges (oriented roughness). Larger clods and tillage ridges perpendicular to the prevailing wind direction are more effective for wind erosion control (12). A cloddy surface will also slow down wind and protect and trap smaller particles, reducing saltation and thereby erosion.
Roughing the surface to prevent wind erosion
Increasing plant cover: Accelerated soil erosion is often associated with deficient vegetative cover and may be partially responsible for societal failures. Vegetative cover is one of the keys to effective erosion control. Vegetation holds soil together, slows wind and traps any moving particles. Vegetative cover can be alive or dead, but needs to be well-attached to the soil. In addition to providing resistance to soil particle detachment and transport, decomposing plant materials give rise to other hallmark functions. These functions, which contribute to the maintenance of dynamic soil organic matter levels, are inherently related to soil erosion control because of increased rainfall capture and retention. The notion is widely held that land management has a profound effect on wind erosion control of the soil surface. In humid and sub-humid climates, the canopy of native vegetation communities is generally sufficient to prevent erosive wind energy from reaching the soil surface. In semiarid and arid climates, however, native plant communities do not fully protect the soil surface from the erosive forces of wind. Semiarid ecosystems including grasslands, shrub land, savanna, woodland, and forests are all susceptible to wind erosion, especially when disturbed by human activities (13).
The effects of vegetation cover on wind erosion and soil loss have been investigated in a section of desert grassland in southern New Mexico. The authors of the study concluded that once lateral cover, a function of plant number density and vertical dimension, drops below 9%, wind erosion increases dramatically (14).
In farmlands, wind erosion may be controlled through tillage, maintenance of a surface cover of growing crops or crop residues, and by surface application of cementing agents. The importance of maintaining a cover of growing vegetation or residue has been recognized for several decades. In addition to controlling wind erosion, the maintenance of surface residues helps conserve water by increasing infiltration and decreasing runoff. While many crops produce sufficient residue to protect the surface, tillage and weathering reduce the amount of residue remaining during the fallow season. Standing residue is much more effective at reducing erosion than flattened residue. In semi-arid regions, drought often limits the production of residue and sparse surface residues have been shown to actually increase wind erosion in some cases. Where residue production is insufficient to protect the surface, tillage can be and is often implemented to control erosion (15).
While the early research on the role of plants in wind erosion control has primarily aimed at developing specific practical solutions to protect cultivated land or human infrastructures, the focus of recent research has shifted towards a more holistic and conceptual perspective. A large number of recent studies focusing not only on cultivated land but also on grazing land and natural ecosystems. They deal with ecological interactions between wind erosion, vegetation, climate and degradation processes on different spatial and temporal scales. In this context, it has been recognized that the loss of protective vegetation cover is often accompanied or preceded by changes in physicochemical and biological soil properties, such as soil structure, plant nutrient availability, organic matter content and microbial activity. With regard to wind erosion control, it has thus been acknowledged to be of critical importance to address not only vegetation cover, but also these biological and physicochemical soil qualities (16).
Type, coverage and arrangement of vegetation has the strongest influence on the ability of wind to reach the soil surface. The patchy and dynamic nature of vegetation in drylands regions results in aeolian transport. They can highly be heterogeneous in both space and time. The amount of material that is moved depends on the size of non-vegetated gaps upon which the wind can act (generally excluding rocky or gravelly areas, referred to as desert pavement, and areas covered by physical or biological soil crust) and the height and density of the vegetation, which controls the size of the protected area downwind of individual plants.
Although surface characteristics are important, the amount of horizontal flux depends largely on the structure of the ecosystem and the degree of connectivity between non-vegetated gaps. Non-vegetated areas immediately downwind of vegetation (within 5–10 times the height of an individual plant) are relatively protected from the erosive force of the wind by the plant. In contrast, non-vegetated areas further downwind from a plant do not experience the same degree of protection from erosion. This disparity leads to heterogeneous erosion and the net movement of soil and litter from non-vegetated gaps, and concentration of these resources beneath plant canopies (17).
An increase in plant density can also cut wind speed. Since this is clearly not easy in arid zones, it is particularly important to ensure sound crop residue management, keeping residues on the ground so as to increase ground roughness and protect the soil surface, rather than further plowing of soils, which would only slightly improve soil structure and resistance to wind. In the semi-arid tropical conditions of West Africa, the large natural stands of Acacia albida, which are prevalent in cultivated zones, provide fairly effective protection against wind erosion by cutting wind-speed at ground level, as well as by shedding leaves onto the ground (18).
Prosopis sp. as windbreak
Windbreaks: Windbreaks are rows of trees or shrubs that reduce the force of wind. They can reduce soil erosion, increase crop yields and protect livestock from heat and cold. Windbreaks can shield buildings and roads from drifting snow. They beautify the landscape, travel routes and provide habitat for wildlife. Windbreaks can also be sources of wood and food. In areas subject to violent blows from a regular direction, hedges and windbreaks are well-known methods. Their role is twofold: cutting down wind-speed, reduction both evaporation and wind erosion. The effect of cutting wind-speed by 20% is operative over an area 10 to 12 times the height of the barrier before and behind it.
Windbreaks are major component of a successful agricultural system throughout the world. The focus is on private and commercial agricultural systems, where windbreaks contribute to both producer profitability and environmental quality by increasing crop production while simultaneously reducing the level of off-farm inputs. They help control wind, blow snow, improve animal health and survival under winter conditions, reduce energy consumption of the farmstead unit, and enhance habitat diversity, providing refuges for predatory birds and insects. On a larger scale, windbreaks provide habitat for various types of wildlife and have the potential to contribute significant benefits to the carbon balance equation. They also ease the economic burdens associated with climate change. Maximizing the benefits of windbreaks requires a thorough understanding of the physical interaction between the wind and the barrier.
In order for a windbreak to function properly, it must be designed with the needs of the landowner in mind. The ability of a windbreak to meet a specific need is determined by its structure: both external structure, width, height, shape, and orientation as well as the internal structure; the amount and arrangement of the branches, leaves, and stems of the trees or shrubs in the windbreak. In response to windbreak structure, wind flow in the vicinity of a windbreak is altered and the microclimate in sheltered areas is changed; temperatures tend to be slightly higher and evaporation is reduced. These types of changes in microclimate can be utilized to enhance agricultural sustainability and profitability (19).
Field shelter-belts increase yields of field and forage crops throughout the world. The increases are due to reduced wind erosion, improved microclimate, snow retention and reduced crop damage by high winds. Crops differ in their responsiveness to shelter. Of the field and forage crops tested, winter wheat, barley, rye, millet, alfalfa and hay (mixed grasses and legumes) appear to be highly responsive to protection, while spring wheat, oats and corn respond to a lesser degree. Shelter-belt height and longevity, field width and shelter-belt orientation are major considerations in determining the effect of shelter-belts on crop yields (20).
The principal benefit of the windbreaks appeared to be reducing wind speed during periods with short duration erosive winds. More than 1 H (height) from the windbreaks, wind erosion was reduced for 36 H downwind of the windbreak that provided most shelter during the period of maximum soil movement. Browsing stock increased the porosity of the lower 1.5 m of the windbreaks, which allowed wind to funnel under the windbreaks. Changes in wind speed and microclimate as a result of wind shelter vary spatially and temporally. When the wind direction was perpendicular to the windbreaks, wind-run reductions greater than 20% extended 18 times the height of the windbreak (H) downwind. However, over the whole growing season wind-run reductions greater than 20% only extended 3–6 H from the windbreaks, and were confined to within 4 H over the whole year. Over the growing season, atmospheric vapor pressure and average daily temperature and potential evaporation in the most sheltered part of the windbreak bay were generally within ± 5 –10% of unsheltered values. While growing conditions were generally improved, there were periods at the end of the growing season when sheltered crops experienced increased air temperatures and vapor pressure deficit (21).
Functional effects of windbreaks are directly related to the effects of windbreaks on airflow. Additionally, the indirect effects of windbreaks on air temperature and humidity are interrelated with the effects of air movement.
The horizontal extent of windbreak effects upwind and downwind is usually assumed to be proportional to windbreak height, h. Measurable reductions in wind-speed have been recorded as far as 50 h to the lee of windbreaks, and sometimes even farther.
The most important structural feature in designing windbreaks is porosity. Maximum wind speed reductions are closely related to windbreak porosity. Barriers with very low porosity create more turbulence downwind than medium-dense barriers. Higher turbulence may result in recovery of mean horizontal wind speeds to upwind speeds closer to low-porosity barriers, thus resulting in a shorter protected distance. However, the reduction in protected distance with very dense windbreaks compared to medium-density windbreaks is much less than much of the older literature suggests. Turbulence in the approach flow reduces windbreak effectiveness, particularly at far downwind positions. The turbulence may be caused by thermal instability, a rough ground surface, or other upwind barriers to flow (22).
When wind, blowing across a surface, encounters large obstacles, such as isolated shrubs, trees or shelter-belts, the vegetation absorbs a proportion of the wind’s momentum, resulting in a reduction of wind speed. This wind-speed reduction proportionally decreases the available shear force to the surface, thereby reducing the wind erosion potential in the lee of the wind barrier.
Land uses, such as livestock grazing and crop production, can cause an increase in the potential for wind erosion because of the removal of natural or planted ground cover and alteration of soil structure. Management strategies to reduce wind erosion have incorporated the use of windbreaks, shelter-belts and structural barriers that result in a reduction of wind speeds in the lee. Ranging practices, particularly on marginal lands, such as in the American Southwest and Australia, have been partly responsible for dust storms, causing health and traffic hazards. Planting or maintaining natural vegetation cover at sufficient canopy densities can eliminate the likelihood of wind erosion. Moreover, on cropped fields, the implementation of windbreaks has the added benefit of creating a favorable micro-climate that can lead to an increase in crop productivity (23).
The best arrangement of a windbreak scheme would be two rows of tall trees surrounded by two rows of low trees, making up an approximately 10-meter strip. The cropped area between wind-breaks can be as wide as 100 meters if the tall trees are over 5 meters. It is particularly important to repair breaches in a hedge to keep the wind from pouring through at these points (the Venturi effect) and considerably reducing effectiveness (24).
Sand dunes fixation: Stabilizing a dune to control the sand movement can be accomplished chemically, mechanically or biologically. Stabilization control measures could be temporary or permanent. A temporary sand control system is used as an initial stage during the application of a permanent one. A temporary system may include shielding the ground with stable material or erection of fences or other methods. Shielding the ground can be accomplished by stone mulching, wetting, chemical stabilizers, biological crusting or covering the ground by any other material such as tree branches, sheets, nets, geo-textiles, or similar materials. The erection of fences can also temporarily control sand hazard.
Fences can be in the form of checkerboards or fore dune fences (impounding fences and diversion fences), and the selection of a fence type is based on the geomorphological condition of the area and the availability of the fence material. Fences can be constructed of plant remains (such as palm leaves), wood, fiberglass or concrete. Porous fences are more efficient than the solid fences, much less costly and fast to erect. Vegetation is, however, the most appealing permanent solution and is accomplished through planting shelter-belts that can survive the local environmental conditions.
The logic of sand dune fixation is to eliminate the sand source and to keep the dunes in place. In places where high winds come from only one direction, wind erosion can be stopped by erecting rows of fences perpendicular to this wind at distances of 20 times the height of the rows. This means that large amounts of available material are needed (such as straw stalks, tamarix, palms branches which grow in desert regions, or pruning from the trees or shrubs found in those regions). However, when the high winds come from a variety of directions, the use of grids of permeable windbreak with a height of 50 to 80 cm is indicated to be essential. The stronger the winds, the smaller the grid, ranging from 5 × 5 m to 8 × 8 m in normal conditions. As soon as this grid is in place and the soil surface has become more stable, a variety of grasses and shrubs must be planted inside it to restore plant cover and definitively stabilize the dune.
There are some very successful examples of various countries combating sand dune fixation in different regions of the world. M. Akram and M. Abdullah have reported one of such exciting experience of sand dunes control in Cholistan desert in Pakistan (25).
Stabilization of sand dunes with perennial vegetation cover is the only sustainable solution to halt sand migration toward irrigated fertile lands, to avoid their abandonment, and to produce timber, wood for fuel, and forage for livestock. This will rehabilitate desertified land, protecting it and surrounding areas against desertification. The stabilization of mobile sand can be achieved by prohibiting free livestock grazing and by re-vegetation with drought resistant species of afforestation trees, shrubs and grasses. Shifting sand had been fixed in India through the implementation of micro-barrier fences in a checkerboard-like arrangement before plants establishment at Dingarh to successfully create an environment for growth of plants. These micro-fences had prevented the movement of sand for long enough to enable natural and planted vegetation to become established. Alternative irrigation with rainwater and saline water helps the plants to grow rapidly. It has therefore played an important role in developing good vegetative cover to protect bare soil against the danger of wind erosion. Perennial tree species, such as. Acacia, Tamarix, Zizyphus, Parkinsonia, Prosopis, Ampliceps and Eucalyptus, have been used to develop excellent vegetation cover on the mobile sandy area affected with wind erosion (26).
Another inexpensive method well-suited to West Africa is that of sowing rows or grids of millet or some other fast-growing plant in the rainy season, thus giving the soil further stability. If the survival of these fragile planted plots is to be assured, it is obviously vital to protect them against grazing and fire, although after five years some light and well-supervised grazing may be possible (27).
There are also very intense activities combating desertification in China. Possessing extensive amounts of arid and semi-arid areas (3.32 million km2), of which 79% located in more than a quarter of the country’s territory and is highly vulnerable to desertification (28). To combat desertification and sand storms, the Chinese government has launched large and costly programs to fix sand and increase vegetation cover. Among these projects, manual plantation and aerial seeding are commonly applied measures (29). In seeding projects, species are selected that can tolerate harsh dune habitats and are able to realize fast plant population expansion. Clonal plants, which often are successful colonizers in stressful environments, are commonly used to fix shifting dunes and prevent sand encroachment in adjacent areas in China and many other desert regions in the world (30).
Along with other research activities to develop methods for sand dune fixation, the investigators have invented a straw checker-box method. The establishment of a straw checker-board changes the structure of the airflow and changes the ground surface status from erosion to deposition. Owing to the deposition of fine particles, a soil crust is formed and soil formation begins. Soil formation has been observed from semi-arid sandy land in north-eastern China to the extremely arid deserts of western China. It has also been observed in sandy lands in Tibet. Soil formation can further stabilize the surface of sand dunes and improve the microenvironment (31).
Biological measures to combat desertification in Iran include techniques to expand dunes fixation using species adapted to the harsh conditions of deserts, planting seedlings, and direct seeding of suitable plant species. Since the first steps were taken to stabilize sand dunes, various plant species have been used. Nearly all species are shrubs, apart from the perennial grass Panicum antidotale (millet). Haloxylon species were used from the early years of desertification control and are the most widely cultivated species in desertified provinces. Only in provinces bordering the coasts of the Persian Gulf and the Sea of Oman and those with more adequate rainfall near the Zagros Mountains, Haloxylon is not used. Haloxylon aphyllum and Calligonum comosum species, used for stabilizing sand dunes in Rezaabad, Semnan province, were shown to improve the physicochemical properties of soil including structure, organic matter, and nutrient status (N,P,K), and to increase the density of Stipagrostis pennata, the native vegetation of the area (32).
Desert plants, which usually grow on sand dunes with loose texture or sandy beaches, include grasses, shrubs and trees. These plants must be able to tolerate rapid sand accumulation, flooding, salt spray, sandblast, wind and water erosion, wide temperature fluctuations, drought, and low nutrient levels. In spite of the severe limits placed on the plant species, plants capable of stabilizing coastal dunes can be established in most coastal regions with enough rainfall to support plant growth (33).
The six primary criteria of desert plants include:
1. Cold resistance and heat resistance:
Most desert plants such as Ammopiptanthus mongolicus could resist severe cold of -25c and can tolerate over 60c land temperature and 70c surface temperature.
2. Strongly favor sunlight:
Atraphaxis bracteata, Calligonum caput-medusa trees grow very well under sand dune desert condition.
3. Sand bury-resistance and wind erosion-resistance:
Twigs of many desert plants are buried by moving sand. If the twigs meet water, they can grow adventitious roots, and can grow new plants on the twigs rapidly, such as Nitraria sp. Some roots are exposed because of strong wind erosion, yet still grow tenaciously, such as Haloxylon and Calligonum.
4. Root developed strongly:
Main roots usually can reach the underground water layer, the longest roots are over ten meters. Haloxylon plants, main root can reach as 13 meters, Alhagi sparifolia, its main root can reach 5 meters deep, such as Calligonum mongolicum; its lateral root can reach 25 meters.
Calligonum polygonoides seeds
5. Drought and barren resistance:
Some desert plants grow well even when the water content rate of the sand dune is less than 2% and the nutrition of the soil is poor, such as Limonium aureum, which can still grow and blossom strongly in 1.68% water content. The endemic plants have mechanisms to adapt the drought conditions .
6. Sprout early, the growth period is long:
Desert plants usually sprout in early April and blossom in May to July. Desert plants grow vigorously; after September their growths go down gradually.
The important plant species used for combating desertification and moving of sand dunes are Hedysarum laeve, H. scoparium, Amorpha fruticosa, Lespedeza bicolor, Caragara microphylla, C. korshinskii, Artemisia halodendron, A. sphaerocephala, Astragalus adsurgens, Ulmus pumila, Hippophae rhamnoides, Haloxylon ammodendron, Calligonum mongolicum. Elaeagnus sp., Fraxinus sp. Robinia pseudeaccucia, etc.), which dry and hot-resistant plants were selected plantations (35).
Haloylon persicum in flower
Conclusion: Wind erosion results in lose of valuable soil and results consequently in desertification. Desertification remains potentially the most threatening element of ecosystem change, impacting the socioeconomic conditions of millions of people living in the drylands. It is caused by complex interactions of a number of physical, biological, political, social, cultural, and economic factors. The global community initially didn’t seriously react to desertification problem. Responses to desertification and its attendant problems were a localized approach. However, it did change to a more structured and well-established function as the intensity of the problem increased. By linking a number of critical environmental problems with socioeconomic conditions, this global treat became an important force in building a multilateral framework for addressing sustainable development practices. It is well recognized that there are several challenging factors that limit the optimal implementation of sustainable ecosystems projects. In order to ensure adequate international co-operation for mutually required resources, the commitments of the involved countries should be quantified. The countries facing the problem should come forward to use advanced technologies to monitor, assess their natural resources, collect reliable data and properly analyze their environmental degradation. International institutions must also encourage sharing experiences and best practices in natural resources management. Strong collaboration needs to be developed with educational institutions, especially, in the whole Middle Eastern countries and other regions where wind erosion and desertification problems are serious, countries such as China, India, Pakistan and Israel. The collective knowledge of these countries will help to not only create awareness on this critical issue, but to enable them to link theory and practice. Creation of a regional network to collect data and conduct research could prove beneficial in combating desertification in the Middle Eastern drylands. Most importantly, joint research facilities can be established which would house the activities of researchers from all countries in the region. Analyses of their research will enable more efficient planning of the region’s ecological and economic development. Since ecosystems, erosion and desertification do not recognize political boundaries, cooperation of all countries in the region is an absolute must if the problem of desertification is to be addressed.
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