Hillslope-Riparian Zone Reservoir Mixing: A Multi- Catchment Test of a New Methodology for Predicting Stream Chemistry

山坡-河岸带储层混合：预测河流化学新方法的多流域测试

• 批准号: 9805475
• 负责人: Jeffrey McDonnell
• 金额: $ 39万
• 依托单位: SUNY College of Environmental Science and Forestry
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2001-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9805475&HistoricalAwards=false
• 关键词: Hillslope; Riparian; Zone; Reservoir; Mixing

9805475McDonnellUnderstanding and predicting streamwater chemical response to perturbations such as climate change and non-point source pollutants requires knowledge of the hydrologic mechanisms controlling streamflow generation and biogeochemical mechanisms influencing solutes transport. Despite the nearly two decades of intensive research in small catchments, no quantitative framework has emerged that specifies the measurements necessary to characterize a given catchment or even provides a context for the interpretation of field measurements. The proposed project seeks to develop such a framework through a combined modeling and field effort.Previous research has indicated that hillslope-riparian reservoir mixing may be the most important control on stream chemistry at the watershed scale. We will conduct a field-modeling study of hillslope-riparian zone mixing at 3 catchments (Panola Mountain, Sleeper River and Maimai New Zealand) spanning a wide range of geomorphic and hydrologic conditions. Our research is based on realizations that: (1) the hillslope may not contribute much directly to streamflow during storm events, (2) the chemical signature of the hillslope is not apparent in the stream during events, thus challenging our traditional view of the stream as integrator of the catchment, and (3) we may not be able to construct whole (including the hillslope) catchment models based upon stream chemistry and hydrology for prediction of future conditions. The ultimate goal is objective delineation of catchments (based on prescribed measurements) into homogeneous reservoirs to provide a general methodology to interpret field observations and develop predictive models. The physical connections among these reservoirs define the hydrologic flowpaths in the catchment. By working at multiple catchments, we hope to be able to discern patterns that are not specific to one catchemtn.Uncertainty analysis will be used. Our objectives are to: (i) develop a new TOPMODEL-based hydrogeochemical reservoir mixing to test our perceptual understanding of flow pathways and runoff production mechanism, consistent with hydrometric measurements, (ii) determine what catchment factors determine hillslope influence on stream chemistry using a watershed cross-comparison, (iii) quantify when hillslope water becomes riparian water, (iv) develop a data-based reservoir mixing model with robust structure to apply generally to upland catchments. This study represents an innovative attempt to link a reservoir mixing, model constrained by both isotope and geochemical data within a topographically-driven hydrologic model at the catchment scale.

9805475 McDonnell了解和预测河水对气候变化和非点源污染物等扰动的化学反应，需要了解控制水流生成的水文机制和影响溶质迁移的地球化学机制。 尽管近二十年的密集研究小集水区，没有量化的框架已经出现，具体说明必要的测量，以表征一个给定的集水区，甚至提供了现场测量的解释背景。 建议的项目旨在开发这样一个框架，通过结合建模和field effort.Previous研究表明，山坡河岸水库混合可能是最重要的控制流化学在流域尺度。 我们将在3个集水区（帕诺拉山，Sleeper河和Maimai新西兰）进行一项山坡-河岸带混合的实地模拟研究，涵盖广泛的地貌和水文条件。 我们的研究基于以下认识：（1）在暴雨期间，山坡可能不会直接对径流产生太大影响，（2）在暴雨期间，山坡的化学特征在溪流中并不明显，因此挑战了我们传统上认为溪流是集水区的组成部分的观点，及（3）我们未必能根据河流化学及水文学，建立整个（包括山坡）集水区的模型，以预测未来的情况。 最终目标是客观地将集水区（根据规定的测量）划分为均质储层，以提供一种通用方法来解释现场观察和开发预测模型。 这些水库之间的物理连接确定了集水区内的水文流路。 通过在多个集水区工作，我们希望能够辨别出不特定于一个集水区的模式。将使用不确定性分析。 我们的目标是：（i）开发一个新的基于TOPMODEL的水文地球化学水库混合，以测试我们对水流路径和径流产生机制的感知理解，与水文测量一致，（ii）使用流域交叉比较确定哪些集水因素决定山坡对河流化学的影响，（iii）量化山坡水何时成为河岸水，（iv）发展一个以数据为基础、结构稳健的储层混合模式，以普遍适用于高地集水区。 这项研究是一个创新的尝试，连接水库混合，模型约束的同位素和地球化学数据在地形驱动的水文模型在流域尺度。