Collaborative Research: The effects of river regulation on lateral and integrated longitudinal mass and energy transfers in coupled terrestrial-aquatic systems

协同研究：河流调控对陆水耦合系统横向和纵向整体质量和能量传递的影响河流和浅层地下水相互联系，不断交换水分；河水暂时流经河床和河岸。河岸的横向交换带（LEZ）影响河流水质，因为LEZ内的微生物群落消耗水生营养物质和溶质。我们对当地LEZ过程如何综合影响大型河流的溪流水质知之甚少。在全球范围内，60%的主要河流由水坝管理，一些水坝管理的河流定期（每天）发生洪水。本研究将研究和了解河流的流动和动态生物地球化学制度如何影响河流走廊上的营养和热能转移。它将导致对人类影响的地表-地下水文系统的生物地球化学过程的理解。通过对德克萨斯州6阶科罗拉多河下游90公里河段的实地观测，并通过对河流和LEZ过程的耦合数值模拟，我们将确定洪水/衰退期间LEZ的动态膨胀/收缩如何控制LEZ内的化学反应速率和热量传递，以及这反过来如何影响河流水质和下游溶质和能量的输送。这项研究将为管理水坝管理的河流提供有用的知识。在所有州中，德克萨斯州拥有最多的水坝，作为最近一项州法案的一部分，该州计划为水利基础设施分配资源。至关重要的是，必须了解河流调节对LEZ过程、地下水和溪流水质以及河流生态的权衡和潜在影响。这方面的研究很少，这项调查将有助于填补这一知识空白。此外，这项研究将培训下一代水文工程师和科学家，并提高公众对河流-地下水相互作用重要性的认识，特别是在受管制的河流范围内。参与研究的学生包括K-12、学士、硕士、博士，以及K-12教师。将为K-12学生组织实地考察。将向公众举办外展讲座。

Collaborative Research: The effects of river regulation on lateral and integrated longitudinal mass and energy transfers in coupled terrestrial-aquatic systemsRivers and shallow groundwater are inter-connected and continuously exchange water; river water temporarily circulates through the beds and banks of rivers. The lateral exchange zone (LEZ) in the banks affects instream water quality since microbial communities in the LEZ consume water-borne nutrients and solutes. We know little about how local LEZ processes integrate to impact instream water quality for large rivers. Globally, 60% of major rivers are regulated by dams and some dam-regulated rivers are subject to periodic (daily) floods. This study will examine and understand how flow and dynamic biogeochemical regimes in regulated rivers impact nutrient and thermal energy transfers through the river corridor. It will lead to understanding of biogeochemical processes in human-impacted surface-subsurface hydrologic systems. Through field observations along a 90-km section of the 6-th order Lower Colorado River in Texas and through coupled numerical simulations of instream and LEZ processes, we will determine how the dynamic expansion/contraction of the LEZ during flooding/recession controls chemical reaction rates and heat transfer within the LEZ, and how this in turn impacts instream water quality and downstream delivery of solutes and energy.The study will generate knowledge that is useful for the management of dam-regulated rivers. Texas has the most dams amongst all states with many more planned as part of a recent state bill that allocates resources for water infrastructure. It is critical that the trade-offs and potential effects of river-regulation on LEZ processes, groundwater and instream water quality, and river ecology be understood. This has seldom been studied and this investigation will help fill this knowledge gap. Further, the study will train the next generation of hydrologic engineers and scientists and increase public awareness of the importance of river-groundwater interactions, particularly within the context of regulated rivers. Students from K-12, BS, MA/MS, to PhD level, and K-12 teachers will participate in the research. Field trips to the site will be organized for K-12 students. Outreach lectures will be presented to the public.