Hydrology and mercury biogeochemistry of the Hudson Bay lowland

哈德逊湾低地的水文学和汞生物地球化学

• 批准号: 217046-2009
• 负责人: Branfireun, Brian
• 金额: $ 2.91万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=497095
• 关键词: Hydrology; mercury; biogeochemistry; Hudson; Bay

The vast majority of research on peatlands and surface water quality has been done in small catchments, often with highly simplified water balances, and this certainly applies to investigations of the role of peatlands in mercury fate and transport. There have been no attempts to scale up the process-based knowledge that we have about Hg cycling in small peatlands to the larger extensive peatland systems of the world. The Hudson Bay Lowlands (HBL) is the second largest contiguous peatland in the world, with a total area of approximately 320 000 sq km. The HBL is in a region that is likely to be subjected to the most significant increases in annual average temperature due to climate change of anywhere in the world. The absence of process-oriented hydrological and water quality data means that the potentially dramatic impacts of a changing climate on the hydrological and biogeochemical processes of the peatlands of the HBL and the subsequent changes to the mercury cycle are unknown. Given the importance of the mercury cycle to northern ecosystems and communities, this is a significant knowledge gap. By undertaking research on the hydrology and mercury biogeochemistry in both the southern discontinuous and northern continuous permafrost zones of the HBL, I hope to: 1) elucidate the contributions of the HBL peatlands to the budget of water, total mercury (THg) and methylmercury (MeHg) of major tributaries of Hudson/James Bay; 2) gain mechanistic insight into the processes that control MeHg production and transport in the extensive peatlands of the HBL with varying ground ice conditions, and; 3) apply a landscape-based model of peatland-watershed processes to the extensive peatland watersheds of the HBL. Research findings will provide important guidance for land-use management and northern communities in a region that is coming under increasing pressure for resource extraction, and offer insights into the potential hydrological and biogeochemical alterations of the more northern rivers as climate change begins to impact the extent of permafrost.

绝大多数关于泥炭地和地表水质的研究都是在小型流域内进行的，通常水平衡高度简化，这当然适用于泥炭地在汞归宿和迁移中的作用的研究。目前还没有尝试将我们所掌握的有关小型泥炭地汞循环的基于过程的知识扩展到世界上更广泛的泥炭地系统。 哈德逊湾低地 (HBL) 是世界第二大连续泥炭地，总面积约 32 万平方公里。 HBL 所在的地区可能会因世界上任何地方的气候变化而遭受最显着的年平均气温上升。 由于缺乏面向过程的水文和水质数据，意味着气候变化对 HBL 泥炭地水文和生物地球化学过程的潜在巨大影响以及汞循环的后续变化尚不清楚。 鉴于汞循环对北方生态系统和社区的重要性，这是一个巨大的知识差距。 通过对HBL南部不连续和北部连续多年冻土区的水文和汞生物地球化学研究，我希望：1）阐明HBL泥炭地对哈德逊/詹姆斯湾主要支流的水、总汞（THg）和甲基汞（MeHg）收支的贡献； 2) 深入了解 HBL 广阔泥炭地中不同地面冰条件下控制甲基汞生产和运输的过程； 3) 将基于景观的泥炭地流域过程模型应用于 HBL 的广泛泥炭地流域。 研究结果将为资源开采压力日益增大的地区的土地利用管理和北部社区提供重要指导，并为随着气候变化开始影响永久冻土范围而对北部河流潜在的水文和生物地球化学变化提供见解。