CAS-MNP: Evaluating Patterns and Controls on Microplastic Accumulation in Floodplains

CAS-MNP：评估洪泛区微塑料积累的模式和控制

• 批准号: 2219334
• 负责人: Samuel Munoz
• 金额: $ 53.03万
• 依托单位: Northeastern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2219334&HistoricalAwards=false
• 关键词: CAS; MNP; Evaluating; Patterns; Controls

Plastic accumulation in the environment is a pervasive global problem with severe consequences for organisms, ecosystems, and human health. Plastics behave like natural materials in the environment in that they are degraded to form smaller particles including microplastics (fragments 5 mm in length). These plastic particles are transported by conventional geomorphic processes including wind and water. The degradation and transport of plastics has led to its accumulation across a range of environments, providing the basis for a global plastic-carbon cycle. However, a key component of the plastic-carbon cycle — namely the transport and storage of microplastics through rivers and floodplains — remains poorly constrained. Understanding where and why plastics accumulate along rivers and floodplains is critical for mitigating and managing plastic pollution because rivers connect plastics production and use upstream to coasts and the open ocean. This project will analyze soil samples to quantify the amount and types microplastics found in different floodplain environments, and relate patterns of plastic accumulation to environmental parameters. The team will co-develop and deliver bilingual educational materials on plastic transport through watersheds for high school students as part of the Beach Sisters program in Lynn, Massachusetts, an environmental justice community. The project will provide mentored research opportunities for an undergraduate and graduate student and support an early career researcher.Floodplains serve as critical sinks for sediments, carbon, and pollutants, but their role in the global plastic-carbon cycle is poorly understood owing to the unique material properties of plastics, and the complex and dynamic processes that mediate floodplain sedimentation. The same geomorphic processes that control floodplain sedimentation should mediate microplastic accumulation in these environments, although the relatively low density of common plastics (~0.05 to 1.5 g/cm3) relative to natural sediments (~1.4 to 2.9 g/cm3) imply that patterns of plastic erosion and deposition across a floodplain will be unique. This project integrates field-based surveys and sampling with geochemical analyses and hydraulic modeling to test a series of hypotheses describing the interaction of flood inundation, flow velocity, geomorphic setting, and the physical and chemical properties of plastics on their accumulation in floodplains. The study will allow the investigators to build a comprehensive model of where and how plastics accumulate across the geomorphic units of a floodplain, providing a basis to quantify microplastic storage along other river-floodplain corridors. More broadly, the project will allow them to test the suitability of settling velocity models developed for natural sediments on plastic particles with different material properties in an observational setting.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

环境中的塑性积累是一个普遍存在的全球问题，对生物，生态系统和人类健康造成了严重影响。塑料在环境中的表现就像天然材料，因为它们被降解成形成包括微​​塑料在内的较小颗粒（片段长5 mm）。这些塑料颗粒是通过包括风和水在内的常规地貌过程传输的。塑料的降解和运输导致其在各种环境中的积累，为全球塑料碳循环提供了基础。但是，塑料碳循环的关键组成部分（即微塑料通过河流和洪泛区的运输和存储）仍然受到巨大约束。了解塑料沿河流和洪泛区积累的何处和为什么对于缓解和管理塑料污染至关重要，因为河流将塑料生产并用在上游到Costats和Open Ocean。该项目将分析土壤样品，以量化在不同洪泛区环境中发现的数量和类型的微塑料，以及塑性积累与环境参数的相关模式。该团队将在环境正义社区的马萨诸塞州林恩（Lynn）的Beach Sisters Program的一部分中共同开发并提供有关高中生的塑料运输的双语教育材料。该项目将为本科生和研究生提供指导的研究机会，并支持早期的职业研究员。植物图是沉积物，碳和污染物的关键水槽，但由于塑料的独特材料以及中等的动态过程，它们在全球塑料碳循环中的作用很少，因此很少理解。控制洪泛区沉积的同样的地貌过程应在这些环境中中值微塑料积累，尽管相对于天然沉积物（〜1.4至2.9 g/cm3）的相对低密度（〜0.05至1.5 g/cm3）暗示着跨洪泛酶的塑料侵蚀和沉积模式是独一无二的。该项目通过地球化学分析和水解建模整合了基于现场的调查和采样，以测试一系列假设，描述了洪水淹没，流速，地貌环境以及塑料对洪泛区积累的物理和化学特性的相互作用。这项研究将使研究人员能够建立一个综合模型，即塑料在洪泛区的地貌单元中积累的位置和如何积累，从而提供了量化沿其他河流泛滥图层的微塑料存储的基础。更广泛地说，该项目将使他们能够测试在观察环境中为具有不同材料特性的塑料颗粒开发的速度模型的适用性。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子和广泛的影响审查标准来评估NSF的法定任务。