فهرست نشریات علمی دسترسی آزاد ایران

BACKGROUND AND OBJECTIVES: The Aral Sea disaster is widely recognized as one of the worst human-caused environmental catastrophes of the twentieth century. The study objectives were to provide a comprehensive ecological assessment of the dried Aral Sea-bed in Kazakhstan to support phytomelioration planning.METHODS: Field work was carried out from 24 April to 20 May 2023, covering an area of 1,071,967 hectares. The study combined climate analysis (1991-2024 data), groundwater surveys (27 observation wells), soil studies (68 soil pits, 348 samples), and vegetation mapping (93 plots) using geographic information system and remote sensing tools. By December 2023, laboratory analyses had been finalized. The mapping of ecological risk zones was conducted through the application of weighted overlay analysis with six parameters.FINDINGS: The study documented extreme desert conditions with only 120 millimeters of annual rainfall and a humidification coefficient K = 0.20. By the year 2050, it is anticipated that the average annual air temperature will rise by 2.0-2.8 degrees Celsius in comparison to the current climate. The groundwater exhibited a high salinity level, varying from 37.6 to 104.6 grams per liter, depths of 1.2 to 5.2 meters. Soils were mostly solonchaks with surface salt content reaching 35.9 percent. A total of 368 plant species were recorded, and black saxaul (Haloxylon aphyllum) plantations exhibiting survival rates ranging from 22 percent and 100 percent. Four distinct classes of forest site conditions were established: favorable (7 percent), marginally favorable (34 percent), unfavorable (27 percent), and unsuitable (32 percent).CONCLUSION: Using six weighted parameters, four ecological risk zones were mapped: low (7 percent), moderate (37 percent), elevated (25 percent), and high (31 percent). The high-risk regions align with bare solonchaks and migrating dunes, identified as the principal contributors to salt-dust storms. The four-tier forest site classification system developed in this study, specifically calibrated for groundwater salinity levels up to 104.6 grams per liter, provides a preliminary scientific foundation for phytomelioration planning under Kazakhstan's National Afforestation Program.