A5101945474- Hydrology and Watershed Management Studies
- Soil and Water Nutrient Dynamics
- Groundwater flow and contamination studies
- Fish Ecology and Management Studies
- Groundwater and Isotope Geochemistry
- Urban Stormwater Management Solutions
- Hydrology and Sediment Transport Processes
- Flood Risk Assessment and Management
- Wastewater Treatment and Nitrogen Removal
- Smart Materials for Construction
- Microplastics and Plastic Pollution
- Cryospheric studies and observations
- Wildlife-Road Interactions and Conservation
- Water Quality and Pollution Assessment
- Geophysics and Gravity Measurements
- Methane Hydrates and Related Phenomena
- Earthquake Detection and Analysis
- Climate variability and models
- Archaeology and Natural History
- Geophysical and Geoelectrical Methods
- Climate change and permafrost
- Hydrology and Drought Analysis
- Arctic and Antarctic ice dynamics
- Hydrological Forecasting Using AI
- Landslides and related hazards
Virginia Tech
2023-2024
Oak Ridge National Laboratory
2022-2024
Vanderbilt University
2017-2024
Waters (United States)
2023-2024
New Mexico Institute of Mining and Technology
2012-2023
Incheon National University
2022
Pacific Northwest National Laboratory
2019-2022
United States Geological Survey
2013-2015
Rivers are important ecosystems under continuous anthropogenic stresses. The hyporheic zone is a ubiquitous, reactive interface between the main channel and its surrounding sediments along river network. We elaborate on physical, biological, biogeochemical drivers processes within that have been studied by multiple scientific disciplines for almost half century. These previous efforts shown modulator most metabolic stream serves as refuge habitat diverse range of aquatic organisms. It also...
Hyporheic exchange has been hypothesized to have basin-scale consequences; however, predictions throughout river networks are limited by available geomorphic and hydrogeologic data models that can analyze aggregate hyporheic flows across large spatial scales. We developed a parsimonious but physically based model of flow for application in basins: Networks with EXchange Subsurface Storage (NEXSS). applied NEXSS broad range diversity reaches synthetic networks. demonstrates vertical beneath...
Hyporheic exchange plays a key role in the biogeochemical evolution of water and ecosystem functioning at local, reach, watershed scales. Residence time is fundamental metric to describe possible transformation taking place this zone. With mind, we use simple conceptual model explore residence distributions (RTDs) sinuosity‐driven hyporheic zones (HZs) discriminate individual effect sinuosity ( σ ), valley slope J x hydraulic conductivity K aquifer dispersivity α L timescales (BTSs) that...
Abstract Downstream flow in rivers is repeatedly delayed by hydrologic exchange with off‐channel storage zones where biogeochemical processing occurs. We present a dimensionless metric that quantifies river connectivity as the balance between downstream and of water bed, banks, floodplains. The degree directly influences quality — too little limits amount exchanged leads to biogeochemically inactive storage, while much contact time sediments for reactions proceed. Using reaction significance...
Lakes, reservoirs, and other ponded waters are ubiquitous features of the aquatic landscape, yet their cumulative role in nitrogen removal large river basins is often unclear. Here we use predictive modeling, together with comprehensive water quality, land use, hydrography datasets, to examine explain influences more than 18,000 on through networks Northeastern United States. Thresholds pond density where become important regional identified shown vary according a waters' relative size,...
Abstract Hyporheic zones increase freshwater ecosystem resilience to hydrological extremes and global environmental change. However, current conceptualizations of hyporheic exchange, residence time distributions, the associated biogeochemical cycling in streambed sediments do not always accurately explain complexity observed streams rivers. Specifically, existing conceptual models insufficiently represent coupled transport reactivity along groundwater surface water flow paths, role...
Abstract Bed form‐induced hyporheic interactions are characterized by a nested system of flow paths that continuously exchange water, solutes, momentum, and energy. At the local scale, sediment heterogeneity plays key role in hydrodynamics potential for biogeochemical transformations within zone. This manuscript explores low‐permeability sedimentary layers on interplay between bed groundwater upwelling. A hydrodynamic conceptualization sequentially couples fully‐turbulent water column...
Abstract Hydrologic exchange fluxes (HEFs) vary significantly along river corridors due to spatiotemporal changes in discharge and geomorphology. This variability results the emergence of biogeochemical hot‐spots hot‐moments that ultimately control solute energy transport ecosystem services from local watershed scales. In this work, we use a reduced‐order model gain mechanistic understanding bank storage sinuosity‐driven hyporheic induced by transient discharge. is first time systematic...
Abstract Discharge varies in space and time, driving hyporheic exchange processes river corridors that affect biogeochemical cycling ultimately control the dynamics of hot spots moments. Herein, we use a reduced‐order model to conduct systematic analysis interplay between discharge variability (peak flow intensities, duration, skewness) streambed topography (bedform aspect ratios channel slopes) their role transport characteristics zones (HZs). We simple robust conceptualization single peak...
Stream water quality can change substantively during diurnal cycles, discrete flow events, and seasonal time scales. In this study, we assessed event responses in surface nutrient concentrations biogeochemical parameters through the deployment of continuous sensors from March to October 2011 East Fork Jemez River, located northern New Mexico, USA. Events included two pre-fire non-monsoonal precipitation events April, four post-fire August September (associated with monsoonal thunderstorms),...
Abstract Small ponds—farm ponds, detention or impoundments below 0.01 km 2 —serve important human needs throughout most large river basins. Yet the role of small ponds in regional nutrient and sediment budgets is essentially unknown, currently making it impossible to evaluate their management potential achieve water quality objectives. Here we used new hydrography data sets found that depending on spatial position within both local catchments larger network, can dominate retention nitrogen,...
Abstract Coupled groundwater flow and heat transport within hyporheic zones extensively affect water, energy, solute exchange with surrounding sediments. The local cumulative implications of this tightly coupled process strongly depend on characteristics drivers (i.e., discharge temperature the water column) modulators hydraulic thermal properties sediment). With in mind, we perform a systematic numerical analysis responses to understand how temporal variability river zones. We identify...
Key Points Age distributions evolve over time under transient flow conditions Transient leads to the emergence of new characteristic scales in ADs Dynamic impact biogeochemical evolution water watersheds and HZs
Abstract Residence times provide vital information on hydrological, geochemical, and ecological processes in watersheds. The common perception is that mean residence watersheds are very short, the order of days to years. However, there growing concern longer centuries millennia not being captured by traditional surface water age‐dating methods. We hypothesize if biased then weathering rates calculated from will be forced unrealistically high match observed solute concentrations. test this...
Abstract Channel discharge, geomorphological setting, and regional groundwater flow determine the spatiotemporal variability of bedform‐induced hyporheic exchange emergence biogeochemical hot spots moments that it drives. Of particular interest, significantly understudied, is role dynamically changing discharge has on process how modulates effects transience. In this study, we use a reduced‐complexity model to systematically explore responses events in systems with different bedform...
Abstract Floodplain inundation poses both risks and benefits to society. In this study, we characterize floodplain across the United States using 5800 stream gages. We find that between 4% 12.6% of a river’s annual flow moves through its floodplains. Flood duration magnitude is greater in large rivers, whereas frequency events small streams. However, relative exchange floodwater channel similar streams with exception water-limited arid river basins. When summed up entire network, 90% occurs...
Transformation and removal of dissolved nutrients pollutants in streams strongly depends on microbial processes streambed sediments. The contact between these solutes communities is mediated by the physical transport from bulk stream to, through, streambed, a process broadly referred to as hyporheic exchange. Even though multiple biological influence rate exchange, we here show that many exchange mechanisms can be represented simply one‐dimensional diffusion process, where...
While there have been advances in understanding the above ground plastic cycle, is still a substantial lack of sources and activation mechanisms pollution affecting entry, fate, transport, transformation impact microplastics into soils, riverbeds, sediment groundwater aquifers.We here present initial outcomes integrated field laboratory analytical experimental approaches mathematical modelling studies to provide mechanistic overall magnitude as well hot spots (and moments) microplastic entry...
Abstract New experimental techniques are allowing, for the first time, direct visualization of mass and momentum transport across sediment‐water interface in streams. These insights catalyzing a renaissance our understanding role stream turbulence plays host critical ecosystem services, including nutrient cycling. In this commentary, we briefly review nature its hyporheic exchange cycling A simple process‐based model, borrowed from biochemical engineering, provides link between empirical...
Abstract Hyporheic exchange is a crucial control of the type and rates streambed biogeochemical processes, including metabolism, respiration, nutrient turnover, transformation pollutants. Previous work has shown that increasing discharge during an individual peak flow event strengthens turnover by enhancing water dissolved solutes. However, due to nonsteady nature process, successive events do not exhibit proportional variations in residence time some cases, can reduce hyporheic zones'...
Sanitary sewer systems are critical urban water infrastructure that protect both human and environmental health. Their design, operation, monitoring require novel modeling techniques capture dominant processes while allowing for computationally efficient simulations. Open flow in sewers rivers intrinsically similar processes. With this mind, we formulated a new parsimonious model inspired by the Width Function Instantaneous Unit Hydrograph (WFIUH) approach, widely used to predict...
Abstract Hydrologic exchange processes are critical for ecosystem services along river corridors. Meandering contributes to this by driving channel water, solutes, and energy through the surrounding alluvium, a process called sinuosity‐driven hyporheic exchange. This is embedded within modulated regional groundwater flow (RGF), which compresses zone potentially diminishes its overall impact. Quantifying role of at reach‐to‐watershed scale requires mechanistic understanding interplay between...