Mechanics of soil erosion by water: Mathematical modelling and laboratory experimentation

水土流失机理：数学模型和实验室实验

• 批准号: RGPIN-2020-06271
• 负责人: Gumiere, Silvio
• 金额: $ 1.89万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=765649
• 关键词: Mechanics; soil; erosion; water; Mathematical

Soil erosion by water is foremost to an accelerated loss of the world's food-producing lands, threatening global food security and water quality. Soil erosion is increasing as a result of long-term human-related activities and its erosion-prone landforms and climate change. The FAO led Global Soil Partnership reports that 75 billion tonnes per year of soil are eroded from arable lands worldwide. Anthropogenic forces that alter the physical landscape cause substantial soil erosion, which harms surface water bodies and therefore necessitating sediment control as essential aspects of catchment management planning. Simulation models are a vital component of attempts to understand the impact of agricultural processes, land-use and climate change on soil erosion. However, nowadays approaches to modelling soil erosion, despite an endless number of available models, have shown little overall improvement in their ability to predict erosion processes. Due to the complexity, multiple scales and time dependence erosion processes are hard to be thoroughly characterized. That is why most of the nowadays models are only based on soil loss experiments in steady-state conditions, with constant-intensity rainfall rater then phenomenological ones. What makes predictive models very limited to the date and soil types they were calibrated The proposed research program is designed to gain deeper insights into the fine-scale physical mechanisms governing soil erosion using cutting edge experimental technics and new modelling frameworks. The uniqueness of this research program lies in the integrated analysis of hydrological and soil conditions (initial and boundary) and subsequent effects on contaminant transport. More specifically, the short-term objectives of the present research program are to develop: (i) high-speed, high-resolution imaging and CT-Scan techniques to simultaneously track sediment particles in shallow overland flow under controlled laboratory conditions; (ii) a very detailed discrete element model associated with the Lattice Boltzmann method (LBM) of the main processes governing soil detachment and transport by water and (iii)a modified version of the model for field and research applications in the form of a WEB-based version for field and research applications, decision maker's, agronomists and engineers.

水的土壤侵蚀是最重要的是加速了世界上粮食生产的土地，威胁着全球粮食安全和水质。由于长期与人类相关的活动及其容易发生的地形和气候变化，土壤侵蚀正在增加。粮农组织领导的全球土壤合作伙伴关系报告说，全球耕地侵蚀了每年750亿吨的土壤。改变物理景观的人为力量会导致大量的土壤侵蚀，这会损害地表水体，因此需要将沉积物控制作为集水管理计划的基本方面。模拟模型是尝试了解农业过程，土地利用和气候变化对土壤侵蚀的影响的重要组成部分。然而，如今，尽管有无数的可用模型，但对土壤侵蚀进行建模的方法几乎没有预测侵蚀过程的能力。由于复杂性，多个量表和时间依赖性侵蚀过程很难彻底表征。这就是为什么当今大多数模型仅基于稳态条件下的土壤流失实验，然后具有恒定强度的降雨量评估者。使预测模型非常局限于校准的日期和土壤类型，拟议的研究计划旨在更深入地了解使用尖端实验技术和新建模框架来控制土壤侵蚀的精细规模的物理机制。该研究计划的独特性在于对水文和土壤条件（初始和边界）的综合分析以及对污染物运输的后续影响。更具体地说，本研究计划的短期目标是开发：（i）在受控实验室条件下，高速，高分辨率成像和CT扫描技术同时跟踪浅层陆上流中的沉积物颗粒； （ii）一个非常详细的离散元素模型与晶格玻尔兹曼方法（LBM）相关联的主要过程，该过程涉及水的土壤脱离和运输水以及（iii）以网络和研究应用程序形式的修改版本的现场版本和研究应用程序的形式，用于现场和研究应用程序，决策者，农工和工程师。