风沙治理工程综合效益分析——以敦煌黑山嘴风沙口为例

Analysis of comprehensive benefits of wind-blown sand control projects:a case study of Heishanzui,Dunhuang,China

通过对敦煌黑山嘴风沙工程治理区和未治理区近地表风动力环境与土壤理化性质对比分析,研究了风沙治理工程下黑山嘴的防风固沙与土壤改良的综合效益,为今后该区域近地表风沙动力过程的深入研究和风沙灾害综合治理提供了借鉴。结果表明:相较于未治理区,敦煌黑山嘴工程治理区的平均风速、起沙风频率均明显降低,输沙强度减小,年输沙势降低85%,大风天气减少;工程治理区土壤各养分及水盐含量也在一定深度明显增加,全氮、全磷、全钾含量在5 cm土层深度增长率分别达到了322.5%、49.3%、15.1%,全氮、易溶盐对其他组分影响增大,土壤肥力显著提升;两区域土壤电导率与易溶盐含量变化趋势相同,但工程治理区两者含量在土壤表层明显增加,应警惕发生地表盐渍化。

Based on the analysis and observation of the near-surface wind power environment and soil physical and chemical properties of the Dunhuang Heishanzui engineering control area and unregulated area,the research studied the wind regime and sand-fixation's comprehensive benefits under the regulated project of Heishanzui.It is helpful for the wind dynamic in-depth study in this region for the future and provides the reference of the sandstorm disaster comprehensive governance.The results show that the average wind speed and the frequency of sand-driving wind are significantly reduced,the intensity of sand transport is reduced,the annual sand transport potential is reduced by 85%,and the windy weather is reduced in the Heishanzui engineering control area compared with the unregulated area.In the same time,the contents of soil nutrients,water and salt increased significantly at a certain depth.Taking total nitrogen,total phosphorus and total potassium as an example,their growth rates reached 322.5%,49.3%and 15.1%at 5 cm depth,respectively.The effects of total nitrogen and soluble salt on other components increased,and soil fertility increased significantly.The change trend of soil conductivity and soluble salt content was the same in the two regions,but the two contents increased significantly in the soil surface in the engineering control area,so we should be vigilant of surface salinization.