Optimization of aeolian soil erosion control with sand fences

沙栅风沙控制优化

• 批准号: 386788973
• 负责人: Dr. Eric Josef Ribeiro Parteli
• 金额: --
• 依托单位: Forschungsgruppe Theoretische Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/386788973?language=en
• 关键词: Optimization; aeolian; soil; erosion; control

This project is motivated by the need for a reliable numerical tool to optimize measures for protecting sediment soil from wind erosion. Control of soil erosion by wind often requires the erection of different arrays of sand fences, which may be applied in combination with vegetation cultivation to reduce wind power and induce deposition. However, evaluating their efficacy to protect large-scale aeolian landscapes based on experiments alone is difficult both due to the long-term processes involved in the bed evolution and because soil morphodynamics depends strongly on local topography and wind behavior. Therefore, a numerical tool for designing optimized strategies to protect soils against wind erosion is required and shall be developed in the present project. The numerical tool couples Computational Fluid Dynamic (CFD) modeling of the average turbulent wind field over the soil and the erected fences with state-of-the-art morphodynamic modeling of sediment landscapes. To validate the simulations, field measurements of the average basal shear stress, height-integrated sediment flux and bed profile evolution shall be performed in the dune field of Jericoacoara, Northeastern Brazil, and the results compared with numerical predictions. Subsequently, the numerical tool shall be applied to derive strategies for optimal soil protection using arrays of fences of different porosity, spacing and height, and under different wind regimes and conditions of sand availability. To investigate the effect of sand fences on the development of vegetation cover, the simulations shall be then extended to include a model for the interaction between wind, particles in saltation and vegetation. This is important to develop improved anti-desertification measures and to address the long-standing problem of dune immobilization.

该项目的动机是需要一个可靠的数值工具，以优化保护沉积物土壤免受风蚀的措施。控制土壤风蚀往往需要建立不同排列的防沙栅，可与植被种植结合使用，以减少风力和引起沉积。然而，评估其有效性，以保护大规模的风沙景观的基础上单独的实验是困难的，由于长期的过程中所涉及的床的演变，因为土壤形态动力学强烈依赖于当地的地形和风的行为。因此，需要一个数字工具来设计优化的战略，以保护土壤免受风力侵蚀，并应在本项目中开发。该数值工具将土壤和竖立围栏上方平均湍流风场的计算流体动力学（CFD）建模与最先进的沉积物景观形态动力学建模相结合。为了验证模拟，应在巴西东北部Jericoacoara沙丘区进行平均基底剪切应力、高度综合沉积物通量和河床剖面演变的现场测量，并将结果与数值预测进行比较。随后，应使用数值工具，在不同的风力状况和沙的可用性条件下，使用不同孔隙度、间距和高度的栅栏阵列，得出最佳土壤保护战略。为了研究沙栅栏对植被发育的影响，模拟应扩展到包括风、跃移颗粒和植被之间相互作用的模型。这对于制定更好的防治荒漠化措施和解决沙丘固定不动这一长期存在的问题十分重要。