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.

塑料在环境中的积累是一个普遍的全球性问题，对生物、生态系统和人类健康造成严重后果。塑料的行为就像环境中的天然材料一样，因为它们会降解形成更小的颗粒，包括微塑料（长度为5毫米的碎片）。这些塑料颗粒通过包括风和水在内的传统地貌过程进行运输。塑料的降解和运输导致其在一系列环境中积累，为全球塑料-碳循环提供了基础。然而，塑料-碳循环的一个关键组成部分-即通过河流和洪泛区运输和储存微塑料-仍然受到很大限制。了解塑料在沿着河流和洪泛平原上堆积的位置和原因对于减轻和管理塑料污染至关重要，因为河流将上游的塑料生产和使用与海岸和公海连接起来。该项目将分析土壤样本，以量化在不同洪泛区环境中发现的微塑料的数量和类型，并将塑料积累模式与环境参数联系起来。该团队将为高中生共同开发和提供关于通过流域运输塑料的双语教育材料，作为马萨诸塞州林恩环境正义社区海滩姐妹篇计划的一部分。该项目将为本科生和研究生提供指导研究的机会，并支持早期的职业研究人员。洪泛区作为沉积物，碳和污染物的关键汇，但由于塑料的独特材料特性，以及调解洪泛区沉积的复杂和动态过程，它们在全球塑料-碳循环中的作用知之甚少。控制洪泛区沉积的相同地貌过程应介导这些环境中的微塑料累积，尽管相对于天然沉积物（~1.4至2.9 g/cm 3），普通塑料（~0.05至1.5 g/cm 3）的密度相对较低，这意味着整个洪泛区的塑料侵蚀和沉积模式将是独特的。该项目将实地调查和取样与地球化学分析和水力模拟相结合，以测试一系列假设，这些假设描述了洪水淹没、流速、地貌环境以及塑料的物理和化学性质对其在洪泛区积累的相互作用。这项研究将使研究人员能够建立一个全面的模型，了解塑料在洪泛区地貌单元中的积累位置和方式，为量化其他河流-洪泛区走廊沿着的微塑料储存量提供基础。更广泛地说，该项目将使他们能够测试沉降速度模型的适用性，这些模型是为具有不同材料特性的塑料颗粒上的天然沉积物开发的。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。