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The occurrence of dust phenomenon in Sistan from the point of view of repetition and continuity in recent years has taken a growing trend. This challenge has intensified in recent years due to the hydrological change of the Hirmand River due to dam construction and drought. With the drying up of Hamun lake, the level of dust collection has increased. The drying of the Hamon wetland bed and the intensification of the dust challenge have seriously threatened the agricultural foundations and natural resources of the Sistan plain, the well reservoirs, facilities, rural dwellings, human health, the reduction of air quality, the reduction of flight safety, etc. The challenge of wind erosion and dust storms and quicksands in Sistan region is formed and aggravated due to the presence of 120-day winds and the dry bed of Hamoons. In order to reduce dust storms and quicksands and according to the proposal of the relevant ministry, a comprehensive dust control plan of Sistan was defined in 2018 in the Research Institute of Forests and Pastures and in the entire Sistan plain with an area of 400 thousand hectares. For this purpose, 10 study groups including weather and climate, soil science, wind erosion, vegetation, surface water, underground water, flood, determination of wetland title, use of wastewater, application of natural resources laws, agriculture, economic and social studies and integration were conducted. In order to provide solutions and provide executive and management plans to reduce the dust of Sistan Plain, after identifying all the resources in the region and preparing step-by-step maps, summarizing and analyzing the data was done. Due to the large extent of Hamuns in Sistan, prioritization of work units was determined using land sensitivity information, and implementation plans were presented only in units with priority one, but land management plans were presented for the entire study area.
The most important areas prone to dust production in Sistan include the bed of the six Hamoons, including Puzak, Cheng Sorkh, Bringak, Saberi, Hirmand and Godzare, which surround the plain of Sistan. The impact of dust from Sabri, Hirmand and Brinkak Hamuns on Sistan (Iranian part) is more than other regions, therefore the purpose of further study was focused on these regions. After being harvested from the bed of the mentioned sands, due to the strong wind energy, they move towards the border in the erosive corridors of Qargari-Pozak, Niatek, Jejink and Rig Chah-Tasuki. Therefore, the containment approach in the harvesting area and the transportation area is different from each other. According to the studies of the Research Institute of Forests and Pastures of the country, 20.7% of the rural areas with a population of 46388 people (12306 households) are caught in dust within the 3 corridors and corridors. .. According to these studies, in the last 5 years, 30 thousand people, equal to 7600 households, from the entire Sistan plain, and 16 thousand people, equal to 3000 households from the wind erosion corridors of Sistan, have left the region for other destinations. Therefore, 7.5% of the population of Sistan migrated from the region to Zahedan, Golestan, Yazd, Mashhad and Birjand, Tehran, Hormozgan, etc. in a period of 5 years (1390-1995).
The general results showed that in terms of land use, 59% of the area of Sistan's Hamuns in the Iranian part is pasture, which consists of 22 types of plants, and the rest are other uses (bare soil, lake, rock, sand dunes, and residential areas). is The characteristics of the energy of erosive winds showed that the sand carrying potential in the Sistan plain is the highest (2535 vector units) in the country, and moving towards the east or south, the average wind speed and the sand carrying potential decrease. In fact, the energy of the erosive winds in the north of the Sistan plain and on the Bringak and Saberi hills is more than in other parts of the plain. Also, the results of wind analysis showed that in all four seasons, the prevailing wind direction in Sistan is north to northwest.
The amount of energy of the erosive winds in the Sistan region has had many temporal and spatial changes, so that its amount is higher in the northern areas of the Sistan plain and decreases as we move towards the south and east. Therefore, it is suggested that the soil protection and stabilization operations should be concentrated in the northern areas of the plain (Bringak and Saberi mounds), which are also the origin of wind deposits in those areas. Stabilization operations inside erosion corridors are not prioritized due to high wind energy, except in critical areas where there are population centers or important infrastructure structures, because it will cause accumulation of sand in agricultural lands, irrigation canals and other infrastructure structures, which will eventually change the topography of the surface. The land will fill rivers and irrigation canals and hydrological changes. Temporal changes in the amount of wind sediment transport potential showed that in the last decade, the energy of erosive winds was more than in recent years. Therefore, planning for each issue should be done on the maximum limit and the highest energy of erosive winds.
The results of determining the sensitivity of land to wind erosion on the surface of Sistan's dunes showed that the western edge of Saberi and Hirmand dunes have a high priority for stabilization. These areas contribute a lot to the production of sand and fine dust due to the arrival of dry rivers in the western margin, which provide new sources of sediment for fine dust and sand storms.
The results of wind sediment distribution showed that the activity of wind sediments in Sistan takes place inside the four erosion corridors. Any development of infrastructure structures such as roads, water resources, railways or population areas and development of agricultural lands inside erosion corridors will face many problems in the future. Failure to pay attention to the location of development projects leads to high costs for maintenance, sediment discharge and more maintenance costs, therefore it is suggested to locate development projects along the sediment transport route.
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