CAREER: Dynamic water table controls on reactive solute transport near the groundwater-surface water interface

职业：动态地下水位控制地下水-地表水界面附近的反应性溶质输送

基本信息

批准号：
1752995
负责人：
Audrey Sawyer
金额：
$ 54.76万
依托单位：
Ohio State University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-03-15 至 2025-02-28
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1752995&HistoricalAwards=false
关键词：
CAREER Dynamic water table controls

项目摘要

Water table fluctuations influence the transport of nutrients and contaminants between soils, groundwater, and surface water. The water table moves up and down over short and long timespans, particularly near rivers. Water table fluctuations introduce oxygen to shallow groundwater, which can react with ecologically important dissolved substances like organic carbon, nitrate, iron and manganese and have cascading effects on contaminants like arsenic. This project aims to understand how groundwater chemistry evolves in response to water table fluctuations over a range of timescales. Field observations, controlled laboratory column experiments, and computer models will quantify the movement of reactive solutes such as oxygen, nitrate, iron, and manganese beneath a fluctuating water table. Results will improve our understanding of dynamic changes in both groundwater and river water quality and the management of these vital water resources. This project will also introduce a broad audience of citizens and future scientists to dynamic surface water-groundwater interactions through the creation of a hands-on outdoor laboratory facility and museum exhibit. Water table fluctuations play an important role in reactive solute transport and water quality near rivers. When the water table rises, entrapped soil air exchanges oxygen with surrounding pore water, which travels downward when the water table falls. The enhanced supply of oxygen stimulates aerobic respiration, nitrification-denitrification, and oxidation of dissolved iron and manganese in groundwater. Water table fluctuations can propagate tens to hundreds of meters into an aquifer in response to changes in river stage. Yet the implications for reactive transport and water quality near rivers remain poorly understood. The overarching goal of this project is to quantify relationships between water table fluctuations, redox transformations, and solute export from aquifers to rivers. This project leverages novel sensor technology to observe the effects of water table fluctuations on groundwater chemistry in controlled column experiments and natural riparian aquifers. The four field sites in this study experience a range of water table fluctuations in response to tides, storms, and seasons. Each site has unique properties that influence reactive transport near the water table. However, pairs of sites also have commonalities in climate, lithology, catchment scale, land use, and geomorphology. Numerical fluid flow and reactive transport models will quantify dynamics in biogeochemical transformation rates and solute fluxes in these riparian aquifers. Observations and model results will be synthesized to generate a quantitative understanding of the effects of water table fluctuations on reactive solute transport in dynamic riparian aquifers.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.

地下水位波动会影响土壤，地下水和地表水之间养分和污染物的运输。地下水位在短时间内和长时间的潘斯（尤其是河流附近）上下移动。地下水位波动将氧气引入浅地下水，这些氧气可以与有机碳，硝酸盐，铁和锰等生态重要的溶解物质反应，并对砷等污染物产生层叠作用。该项目旨在了解地下水化学如何响应在各个时间尺度上的地下水位波动而发展。现场观测，受控实验室实验和计算机模型将量化反应性溶质的运动，例如氧气，硝酸盐，铁和锰在波动的地下水位下。结果将提高我们对地下水和河水质量的动态变化以及这些重要水资源的管理的理解。该项目还将通过创建动手的户外实验室设施和博物馆展览来向广泛的公民和未来科学家介绍动态的地表水水互动。地下水位波动在河流附近的反应性溶质传输和水质中起着重要作用。当地下水位升起时，被夹住的土壤空气与周围的孔隙水交换，当地下水位掉落时，孔就会向下行驶。氧气供应的增强刺激了有氧呼吸，硝酸化 - 硝化剂以及地下水中溶解的铁和锰的氧化。水桌波动可以响应河流阶段的变化，将数十至数百米的含量传播到含水层中。然而，对河流附近的反应性运输和水质的影响仍然很少。该项目的总体目标是量化水表波动，氧化还原转换和从含水层到河流的溶质出口之间的关系。该项目利用新颖的传感器技术观察受控柱实验和天然河岸含水层中地下水的影响对地下水化学的影响。这项研究的四个现场地点经历了一系列水桌波动，以响应潮汐，风暴和季节。每个地点都有独特的特性，会影响地下水位附近的反应性传输。但是，成对的地点在气候，岩性，集水量表，土地使用和地貌学上也有共同点。数值流体流量和反应性传输模型将量化这些河岸含水层中生物地球化学转化速率和溶质通量的动力学。观察结果和模型结果将被合成，以产生对动态河岸含水层中地下水位波动对反应性溶质转运的影响的定量理解。该奖项反映了NSF的法定任务，并被认为值得通过基金会的知识分子优点和更广泛的影响来通过评估来获得支持。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Groundwater‐stream connectivity from minutes to months across United States basins as revealed by spectral analysis

光谱分析显示，美国流域地下水流连通性从几分钟到几个月不等

DOI：
10.1002/hyp.14514
发表时间：
2022
期刊：
Hydrological Processes
影响因子：
3.2
作者：
Clyne, Jacob B.;Sawyer, Audrey H.
通讯作者：
Sawyer, Audrey H.

Nitrate Removal Within Heterogeneous Riparian Aquifers Under Tidal Influence

DOI：
10.1029/2019gl085699
发表时间：
2020-05
期刊：
Geophysical Research Letters
影响因子：
5.2
作者：
C. Wallace;A. Sawyer;M. Soltanian;R. Barnes
通讯作者：
C. Wallace;A. Sawyer;M. Soltanian;R. Barnes

A Model Analysis of the Tidal Engine That Drives Nitrogen Cycling in Coastal Riparian Aquifers

沿海河岸含水层驱动氮循环的潮汐发动机模型分析

DOI：
10.1029/2019wr025662
发表时间：
2020
期刊：
Water Resources Research
影响因子：
5.4
作者：
Wallace, Corey D.;Sawyer, Audrey H.;Barnes, Rebecca T.;Soltanian, Mohamad Reza;Gabor, Rachel S.;Wilkins, Michael J.;Moore, Myles T.
通讯作者：
Moore, Myles T.

On-Campus Field Experiences Help Students to Learn and Enjoy Water Science During the COVID-19 Pandemic

校园实地体验帮助学生在 COVID-19 大流行期间学习和享受水科学

DOI：
10.3389/fenvs.2022.877327
发表时间：
2022
期刊：
Frontiers in Environmental Science
影响因子：
4.6
作者：
Saup, C.;Lamantia, K.;Chen, Z.;Bell, B.;Schulze, J.;Alsdorf, D.;Sawyer, A.H.
通讯作者：
Sawyer, A.H.

Spectral analysis of continuous redox data reveals geochemical dynamics near the stream–aquifer interface