Abstract:
Background Ulan Buh Desert is located on the west bank of the Inner Mongolia section of the Yellow River Basin, which is the most active interruption of wind and sand in the Yellow River Basin. The continuous expansion of Ulan Buh Desert not only constitutes a serious challenge to the security of water resources in the Yellow River Basin and the security of key infrastructures, but also profoundly affects the living environment of the people and the ability of sustainable development. The Ulan Buh Desert, which is close to the Yellow River, accounts for 77% of the total area of Dengkou county, which is of great significance for the protection of the Yellow River's water resources and desertification prevention and control. Only by deeply exploring the wind condition environment and particle size characteristics of this place, can we provide theoretical basis for the desertification control engineering measures in this place and maximize the effectiveness of the function of desertification control measures.
Methods This study took Dengkou county as the study area, and based on the hour-by-hour wind speed, wind direction and other data monitored by Dengkou meteorological station from 2018 to 2023 and the collection of field surface sand and gravel data, systematically analyzed the characteristics of the wind conditions and sand transport potential of sand-raising winds, as well as the characteristics of the gravel grain sizes under different desertification control and prevention measures.
Results 1) The average annual sand-driving wind speed in Ulan Buh Desert between 2018 and 2023 was 7.08 m/s, and the average annual sand-driving wind frequency was 27.30%, with the maximum wind speed reaching 20 m/s, and the sanding activity was the most active in spring. The dominant wind direction of the sand-driving winds was consistent throughout the year and was dominated by westerly winds (SW, WSW, W and WNW) and easterly winds (NE, ENE and E). 2) The annual (2018–2023) drift potential (DP) and resultant drift potential (RDP) of the Dengkou in the Ulan Buh Desert were 390.86 VU and 249.83 VU, respectively, which belonged to the medium wind energy environment, with a directional variability index of 0.64, which belonged to the medium variability, and resultant drift potential direction (RDD) of 88.81°. 3) Comparing the mobile sand dune area as a control with other protection areas, the average particle size comparison was Border-locked forest zone (38.93 μm) < Farmland protection forest zone (81.28 μm) < Haloxylon ammodendron plantation zone (177.31 μm) < Enclosed zone (192.75 μm) < Ungoverned mobile sand dunes (232.08 μm) < Photovoltaic sand control zone (242.49 μm) < PLA sand barrier zone (243.20 μm).
Conclusions When developing sand control programs, sand control measures should be perpendicular to the westerly winds to prevent them from transporting sand sources to the east. Among the different sand control measures, the average particle size of the border-locked forest zone is smaller, and the effect of this sand control measure is the most significant, and a variety of measures should be created to build together, which has maximized the benefits of sand control.