Cumulative effects on sediment and associated chemical fluxes at the landscape scale: the role of geomorpological connectivity

景观尺度上沉积物和相关化学通量的累积效应：地貌连通性的作用

• 批准号: 341995-2013
• 负责人: Owens, Philip
• 金额: $ 1.97万
• 依托单位: University of Northern British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=633931
• 关键词: Cumulative; effects; sediment; associated; chemical

One of the current research themes in environmental science is how natural and anthropogenic pressures or stressors - such as climate change, land-use activities like forestry and mining, and natural events like wildfires - affect water resources and aquatic ecosystems. This interest is driven by the recognition that most, if not all, water bodies are affected by multiple stressors (often termed cumulative effects) that impact water quantity (e.g. water flows) and water quality (e.g. chemistry, sediment concentrations). The objective of this research project is to determine the cumulative effects of multiple stressors on the environment by focusing on the Quesnel River Basin (QRB, ca. 12,000 km2) in central British Columbia. The overall research project will specifically focus on how geomorphological connectivity (e. g. linkages between land and rivers, and linkages within channels) influences the transfer of sediment and associated chemicals - like trace metals (i.e. arsenic, copper, zinc), nutrients (e.g. phosphorus) and particulate carbon - due to stressors acting in the QRB. One project will evaluate the role of storage elements (specifically glacial forefields, riparian buffers, floodplains, and channel beds) in controlling how sediment and associated chemicals move through landscapes that have been influenced by climate change and land-use activities. In particular, this project will determine if such storage elements attenuate and/or modify material flows and fates. A second project will employ a nested monitoring program in conjunction with sediment tracers, to follow the movement of sediment and chemicals downstream of specific land-use activities such as agriculture, forestry and mining. A third project will use existing spatially distributed models to examine the role of geomorphological connectivity on sediment and associated chemical responses to stressors at the watershed-scale, utilizing the empirical information obtained from the first two projects and an existing GIS platform available for the QRB. The work will provide an improved understanding of how watersheds respond to cumulative effects in a rapidly changing world, which will help to protect water resources and aquatic habitats in Canada.

当前的环境科学研究主题之一是自然和人为压力或压力源（例如气候变化，林业和采矿等土地利用活动）如何影响水资源和水生生态系统。这一兴趣是由认识到，大多数（如果不是全部）水体受到影响水量（例如水流）和水质（例如化学，沉积物浓度）的多种压力源（通常称为累积效应）的影响。该研究项目的目的是通过重点关注不列颠哥伦比亚省中部的Quesnel河流盆地（QRB，12,000 km2）来确定多种压力源对环境的累积影响。整个研究项目将专门关注地貌连通性（例如，土地与河流之间的联系以及渠道内的联系）如何影响沉积物和相关化学物质的传递，例如微量金属（即砷，铜，锌），营养素（例如，磷）和颗粒碳 - 由于压力碳 - 由于压力型 - 由于压力符 - 构成了QRB的压力。一个项目将评估存储元素（特别是冰川前场，河岸缓冲液，洪泛区和河道床）的作用在控制沉积物和相关化学物质如何通过受气候变化和土地利用活动影响的景观中移动。特别是，该项目将确定此类存储元素是否会减弱和/或修改材料流和命运。第二个项目将与沉积物示踪剂一起采用嵌套的监测计划，以遵循特定土地利用活动（例如农业，林业和采矿）下游的沉积物和化学物质的运动。第三个项目将使用现有的空间分布模型来检查地域尺度上的地貌连通性在沉积物和相关的化学反应上的作用，并利用从前两个项目获得的经验信息以及可用于QRB的现有GIS平台的经验信息。这项工作将对迅速变化的世界中的流域如何应对累积效应有了深刻的了解，这将有助于保护加拿大的水资源和水生栖息地。