Advancing Numerical Model for Fate and Transport of Microplastics in the Marine Environment

推进海洋环境中微塑料的归宿和迁移的数值模型

• 批准号: RGPIN-2022-03908
• 负责人: Niu, Haibo
• 金额: $ 1.89万
• 依托单位: Dalhousie University
• 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=752736
• 关键词: Advancing; Numerical; Model; Fate; Transport

The intense and continuous release of plastics into the environment has caused their accumulation in all major marine habitats including Canadian Arctic. Because of their potential risks to marine biota, ecosystem, and human health, the microplastic (MP) pollution has become a major concern for scientists, governments, and even lay person. Numerical model is a key tool for plastic management which can be used to track their origin, predict their trajectory, and identify hotspot of risks. The existing models for fate/transport of MPs in the marine environment are still very limited due to their low resolution and lack of comprehensive weathering processes. Oil-spill model methodology has been proved to be very useful in tracking oil slicks which makes it a good candidate for adapting them for the purpose of tracking MPs and simulating their weathering processes. My previous NSERC Discovery Grant has focused on developing oil spill models for Canadian waters, which has established the important foundation for expanding my research program in advancing numerical model to include emerging contaminants, such as MPs.    The specific objectives are to: 1) developing high-resolution hydrodynamic/ice models to provide the current and ice fields for subsequent fate/transport modelling; 2) better understanding of the settling behaviours of MPs of various shapes to support the development of equations for fate/transport modelling; 3) developing 3D MP fate/transport model (open water condition) that considers various weathering processes such as aggregation, degradation, biofouling, and settling; 4) continue developing the fate/transport model for ice covered conditions; and 5) conducting risk assessment of MPs to marine biota by comparing the hazard with the exposure. This research covers both fundamental research (studying settling behaviours of MPs) and applied research (development of numerical tools & risk assessment). The novelties include: 1) generating new knowledge on the complex settling behaviours of irregular shaped MP particles; 2) producing better hydrodynamic/ice forcing using unstructured grid model for simulation of pathways of MPs in Arctic environment; 3) significant enhancement of existing simple particle tracking models by implementation of comprehensive weathering model; 4) providing new information on high risk areas for marine organism in Canadian waters such as Strait of Georgia and Canadian Arctic Archipelago. The most significant outcomes of this research program are: 1) availability of an advanced numerical model to help us understanding the distribution of MPs in the marine environment; 2) having the ability to quantify risks to marine organisms from exposure to MPs; 3) availability of a technology to support development of policy on management of marine plastics. Application of these models can have environmental benefits to protect marine organisms, and this could also bring economic benefits to Canada.

大量和持续的塑料释放到环境中，导致它们在包括加拿大北极地区在内的所有主要海洋栖息地积累。由于其对海洋生物群，生态系统和人类健康的潜在风险，微塑料（MP）污染已成为科学家，政府甚至非专业人士的主要关注点。数值模型是塑料管理的重要工具，可用于跟踪其来源，预测其轨迹，并识别风险热点。由于分辨率低和缺乏全面的风化过程，现有的海洋环境中MP的归趋/迁移模型仍然非常有限。溢油模型方法已被证明是非常有用的，在跟踪浮油，这使得它成为一个很好的候选人，以适应他们的目的，跟踪MP和模拟其风化过程。我以前的NSERC发现补助金专注于开发加拿大沃茨的溢油模型，这为扩大我的研究计划奠定了重要基础，在推进数值模型，包括新兴的污染物，如MP。 具体目标是：1）开发高分辨率的水动力/冰模型，为随后的归宿/迁移建模提供海流和冰场; 2）更好地了解各种形状的MP的沉降行为，以支持归宿/迁移建模方程的开发; 3）建立MP的三维归趋/迁移模型（开放水域条件），考虑了各种风化过程，如聚集、降解、生物淤积和沉降; 4）继续开发冰盖条件下的归宿/迁移模型; 5）通过比较危害与暴露，进行MP对海洋生物群的风险评估。 该研究涵盖基础研究（研究MP的沉降行为）和应用研究（开发数值工具和风险评估）。这些创新包括：1）产生关于不规则形状MP颗粒的复杂沉降行为的新知识; 2）使用非结构化网格模型模拟北极环境中MP的路径，产生更好的水动力/冰强迫; 3）通过实施综合风化模型，显著增强现有的简单颗粒跟踪模型; 4）提供了加拿大沃茨海洋生物高风险区的新信息，如格鲁吉亚海峡和加拿大北极群岛。 该研究计划最重要的成果是：1）先进的数值模型的可用性，以帮助我们了解MP在海洋环境中的分布; 2）能够量化暴露于MP对海洋生物的风险; 3）技术的可用性，以支持制定海洋塑料管理政策。这些模式的应用可以对保护海洋生物产生环境效益，也可以为加拿大带来经济效益。