Desertification and It's Control in IRAN

Wind erosion and its destructive effects on natural resources and the environment has been a serious problem in Iran from the older times, and though there had been efforts to control it, it was not until 1965 that an organized attempt for checking the phenomenon was launched by establishment of a station in an area of 100 hectares south of Sabzevar, Khorasan province.

The objectives were protection of the environment; stabilization of shifting sands and dunes; preservation of farming lands, conservation of water resources including Ghanat system, and water supply installations; protection of roads and communication networks; and reclamation of settlements and prevention of the inhabitants'emigration.

Basically, wind erosion control involves land salvage and revegetation in areas that are subjected to it because of denudation.

The results of more than 25 years of sand dune fixation activities in the country are plantation of one million hectars with seedlings and 2 million hectars of seeding which has protected or rehabilitated more than 4 million hectars of Iranian arid lands.

Today, after carrying out experiments, researches, and projects for decades on dune stabilization and rehabilitation of desertified lands, Iran can intensify this activities, and supply efficient technical aids to the countries who face the problem.

Due to Iran geographical situation and topographical features, about 80% of Iran's total area have arid or semiarid climate. Alborz mountain chain in north and Zagros mountain chain in west have surrounded the central part of the country. In this central region the average annual precipitation is negligible varying from 50-250 mm and in most parts does not exceed 100 mm. Despite numerous difficulties and rigorous conditions of living in arid regions and deserts, man has adapted himself to it through centuries and has established settlements there and engaged in taming and animal husbandry. Villages of arid regions are mostly tiny, remote and scattered, surrounded by vast expanses of desert.

Animal life, plant cover, and natural resources of desert lands and arid regions are very sensitive and fragile and are easily offended by destructive factors.
Overgrazing, excessive shrub and other vegetation cutting for fuel, and converting the rangelands to agricultural ones are three main factors which devastate pastures and strip the vegetation plant cover.

Unrestrained growth of population and hence unsparing use of plants for fuel and other irrational use of natural regulation tends to denude the soil and intensify desertification. Denuded soil is exposed to wind erosion and shifting sand dunes destroy orchards, gardens, farming lands and threaten industrial and economic centers.

This eventually leads to total collapse of economy, devastation of the environment, abandonment of settlements and emigration of the inhabitants to other cities and residential centers, which in tum rises numerous new difficulties and problems.

 

WHAT SHOULD BE DONE?

Doubtless the most rational and efficient way to stabilize the shifting sands, rehabilitation of plant cover and reclamation of ecological conditions. But since the soil is not stable, sometimes it is necessary first to stabilize it temporarilly against movement with windbreaks or pallisades. Windbreaks are barriers of shrubs, woven canes, and tree branches which are placed over dunes in rows or crosslined patterns.

Another efficient way of temporary stabilization of dunes and creating opportunity for seeds and seedlings to grow and strike root is mulching. Mulch is a substance obtained from petroleum during refining. Mulches, after extraction of aromatics and adding chemical additives as performelation (which varies according to areas), is carried in tankers to the area. Mulches are heated there and sprayed over soil by special devices.

But for permanent stabilization of dunes, plant cover must be fully restored. This may be carried out through seeding, plantation of seedlings, and cuttings. The required seeds may be partly obtained from other planted areas and partly from natural forests of deserts. The required seedlings are grown in nurseries either in bed or plastic pots. The most frequently used seedlings in stabilization of dunes are as follows:

Haloxylon SPP
Tamarix SPP
Zygophyllum eurypterum
Stipagrostis pennuata
Calligonum SPP
Calotropis procera
Atriplex SPP
Acacia SPP
Prosopis spicigera
Nitraria schoberi
Panicum SPP

To secure a satisfactory result, in arid areas it is necessary to irrigate the planted seedlings several times in the first two years. Water can be supplied through temporary pipelines or transported by tankers. Planted areas become completely stabilized and biologically productive after two or three years.

As a result of the implementation of dune stabilization and desert elimination programs, a good opportunity was provided for revegetation and restoraion of the ecological conditions in the region, where the continuity of biological reproduction is assured by the restoration of nature's life cycle.

Reclamation of natural resources and plant cover in desert lands is a difficult and challenging task, but it will bear fruitful results, if it is carried out with rational and proper planning. Thus stabilization of dunes helps to protect residential areas, roads and valuable economic resoureces. ... and so deserts, once bare and barren, become wood and fodder producing centers.

Today, in Iran, as a result of implementation of dune stabilization projects, not only plant cover of vast expanses of deserts has been rehabilitated, but also parts of these lands have been converted to agricultural or industrial ares with vast farming lands and several industrial and economic centers.

More than a quarter of a century of widespread activities in the filed of drifting - sand stabilization, and desert elimination, and the experience gained in their practical application, have placed Iran in the rank of the world's leading and authoritative countries, in regard of the practical application of sand stabilization and desert elimination programs.

Since the menace of the progressing deserts and drifting sands constitutes the common problem of several countries in the region, as well as of certain areas of the Asian and the African continents, Iran's experience and the progress achieved by Iran in this field, may well constitute path- breakers for the interested countries.

Looking forward with hope to the day when the expansion of deserts in the wide world will be stopped and today's wastelands converted into areas fit for living and production.