Biogeochemical Tracers in Arctic Rivers: Linking the Pan-Arctic Watershed to the Arctic Ocean

北极河流中的生物地球化学示踪剂：连接泛北极分水岭与北冰洋

• 批准号: 0229302
• 负责人: Bruce Peterson
• 金额: $ 164.84万
• 依托单位: Marine Biological Laboratory
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-10-01 至 2007-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0229302&HistoricalAwards=false
• 关键词: Biogeochemical; Tracers; Arctic; Rivers; Linking

The overall objective of this proposal is to use river water chemistry as a means to study the origins and fates of continental runoff. Tracers in addition to temperature and salinity are needed to identify river contributions to surface waters of the Arctic Ocean because melting of sea ice confounds interpretation of temperature-salinity mixing models. Furthermore, tracers provide a means to distinguish contributions from different rivers regionally. A 5-year project is proposed in which selected parameters focusing on tracers of river water will be measured in the largest 6 rivers that drain the watershed of the Arctic Ocean: the Yenisey, Lena, Ob', Mackenzie, Yukon, and Kolyma. Tracers to be measured include H218O, barium, organic matter, alkalinity, and nutrients. Sampling will be conducted during the high flow season in Years 1 and 4 and during all seasons in Years 2 and 3. Synthesis and modeling will occur throughout the 5-year project. Samples will be collected near the mouths of the rivers (but above tidal influence) in order to get fully integrated watershed signals and the most relevant freshwater end member values for oceanographic tracking. To investigate transport pathways of river waters through the Arctic Ocean, newly defined end member values will be examined in the context of existing and growing oceanographic tracer databases. To study watershed sources, tracers will be examined in the context of geomorphology, land cover, and hydrology models. The proposed work will also generate a synoptic pan-arctic database on river biogeochemistry for comparison with past and future data in trend analyses. A collaborative network of expertise to successfully sample the 6 largest arctic rivers was assembled. Scientists from 4 nations are involved, including representatives of agencies responsible for water quality monitoring in the Russian, Canadian, and US Arctic. The research group is also in a strong position to analyze and synthesize information on river tracer fluxes into and through the Arctic Ocean at the pan-Arctic scale because of the diverse expertise brought to the project by hydrologists, biogeochemists, and oceanographers. Outreach will involve participation of high school students living in villages near the study sites. Under the supervision of local teachers or researchers, these students will collect water samples from their rivers. They will perform basic analyses such as temperature, pH, and conductivity. Participating students will also be active in exchange of data via the web where available. Scientists from the research group will visit the students and discuss the project, present lectures to their classes, and involve the students in as many aspects of the project as possible.

这项建议的总体目标是利用河水化学作为研究大陆径流的起源和命运的一种手段。除了温度和盐度外，还需要示踪剂来确定河流对北冰洋表层水域的贡献，因为海冰的融化混淆了对温度-盐度混合模型的解释。此外，示踪剂提供了一种手段来区分不同河流的区域贡献。提出了一个为期5年的项目，将在排放北冰洋分水岭的6条最大的河流：叶尼西河、莱纳河、奥布河、麦肯齐河、育空河和科利马河中测量侧重于河水示踪剂的选定参数。被测量的示踪剂包括H_(18)O、钡、有机物、碱度和营养素。采样将在第1年和第4年的旺季进行，并在第2年和第3年的所有季节进行。综合和建模将在整个5年项目中进行。将在河口附近(但在潮汐影响之上)采集样本，以获得完全综合的分水岭信号和最相关的淡水末端成员值，以便进行海洋跟踪。为了调查河流水域通过北冰洋的运输路径，将在现有的和不断扩大的海洋示踪剂数据库的背景下审查新定义的末端成员值。为了研究分水岭来源，将在地貌、土地覆盖和水文模型的背景下研究示踪剂。拟议的工作还将生成一个关于河流生物地球化学的泛北极天气数据库，以便在趋势分析中与过去和未来的数据进行比较。建立了一个成功采集北极6条最大河流样本的专家协作网络。来自4个国家的科学家参与其中，其中包括负责俄罗斯、加拿大和美国北极水质监测的机构的代表。由于水文学家、生物地球化学家和海洋学家为该项目带来了不同的专业知识，研究小组在分析和综合泛北极范围内流入和通过北冰洋的河流示踪剂通量的信息方面也处于有利地位。外展将包括居住在研究地点附近村庄的高中生参与。在当地教师或研究人员的监督下，这些学生将从他们的河流中采集水样。他们将执行基本的分析，如温度、pH和电导率。参与的学生还将积极通过网络交换数据(如果有)。研究小组的科学家将拜访学生并讨论该项目，向他们的班级讲课，并尽可能多地让学生参与该项目的各个方面。