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The “Hydroecology of Flowing Waters” project was initiated in 1998 with the aim to improve understanding of how stream and river corridors function naturally in ways that produce valuable ecosystem services (e.g. flood attenuation, carbon and nutrient storage and contaminant removal, habitat value for fish and wildlife, recreation). The research is increasingly focused on how aquatic ecosystem services can be better protected in the face of degradation resulting from accelerating land use and climate change. Central to the research is the investigation of interactions between physical and biological processes, e.g. how land use change affects hydraulics and channel geomorphology in ways that produce cascading...
1) Improve predictions of streamflow at ungaged basins, and 2) understanding the causes of streamflow changes due to human changes to the environment, and 3) establish biological-flow relations.
To study the mechanisms, pathways, and rates of transformation of carbon and nitrogen compounds (natural and contaminant) mediated by microorganisms in aquatic habitats and identify factors controlling these transformations and to examine the effect that these transformations have upon other biogeochemical processes.
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Collection of 4 assessments for Upland Streams and Rivers. The Condition Index ranks stream segments according to how well they meet the Desired State described qualitatively and quantitatively in the draft Integrated Science Agenda (v4). From the Condition Index, 3 assessments are derived that rank opportunities for management and restoration of conditions included in the Condition Index – Watershed Land Use, Riparian Cover, and Stream Meander. Watershed Land Use management opportunities are based on the proportion of undisturbed land in the contributing (i.e. cumulative) watershed such that stream segments meeting the Desired State are considered Maintenance opportunities (values 5-6). Those that do not meet the...
Toxic contaminants and naturally occurring substances found in the subsurface can exist in multiple phases, and undergo complex reactions including biodegradation. A comprehensive and quantitative understanding of the processes controlling the fate and transport of subsurface contaminants is necessary to develop policies and strategies for managing water-quality conditions in different land use and environmental settings. Numerical models that simulate flow, transport, and reactions are useful tools for understanding the fate of chemicals in the subsurface when used in conjunction with field and laboratory studies. The research efforts of this project consider flow and chemical behavior in the saturated and unsaturated...
Using long-term data records, this project is focused on two problems of importance to water resources managers. First, long-term streamflow records are being used to a) identify broad regional to national trends in floods and low-flows and relate them to possible causes (climate change, water management changes, land-cover changes, and ground-water level change) and b) determine whether there are patterns that relate to watershed size or climate characteristics. It is often stated in the popular press and in official publications on global climate change that we can expect increased variability, including larger and/or more frequent floods, and deeper and longer droughts, as a result of greenhouse warming. This...
The NRP had its beginnings in the late 1950's. Since that time, the program has grown to encompass a broad spectrum of scientific investigations. The sciences of hydrology, mathematics, chemistry, physics, ecology, biology, geology, and engineering are used to gain a fundamental understanding of the processes that affect the availability, movement, and quality of the Nation's water resources. Results of NRP's long-term research investigations often lead to the development of new concepts, techniques, and approaches that are applicable not only to the solution of current water problems, but also to future issues that may affect the Nation's water resources. Basic tools of hydrology that have been developed by the...
Categories: Project; Types: ScienceBase Project; Tags: Acid Mine Drainage, Aquatic Habitat, Arid Land Hydrology, Carbon Cycle, Contaminant Reactions and Transport, All tags...
My research focuses on the application of remote sensing to rivers as a means of more efficiently characterizing fluvial systems, primarily channel form and behavior. More specifically, I develop, test, and apply methods of measuring various river attributes, such as depth, streambed composition, turbidity, and flow velocity, from different types of remotely sensed data, including multi- and hyperspectral images and near-infrared and green LiDAR. These techniques provide higher resolution, essentially continuous data over larger spatial extents than could be surveyed via conventional field methods and thus could facilitate river research and management. My research involves a combination of numerical radiative...
Many difficult problems in river mechanics may have stemmed from inadequate understanding of the multiplicity and interaction of fluvial processes. Some of the problems may have been solved, but in a very simplified, approximate way. Many efforts have been directed, but without apparent success, to fully account for the causes, occurrences, and mechanisms of catastrophic events, such as flash floods, debris flows, and channel changes resulting from torrential storms, sudden snow or glacier melt, dam break, volcanic eruptions, and earthquakes. Such failures may be partially attributed to the deficiency and incompleteness of existing empirical formulas (or models) representing the relationships between various processes...
To provide useful tools in river hydraulics, sediment transport, and geomorphology that: can be used to predict the impacts of man’s activities in rivers, canals, and reservoirs; can forecast the natural evolution of fluvial courses of water; provide analytic and computational platforms to study hypothesis; and enhance our understanding of fluvial morphodynamics.
Human activities from climate change to waste discharges to water management are modifying ecosystems across the earth, often in ways that are not well understood. This project addresses the problem of better understanding changes in aquatic ecosystems as driven by human disturbances interacting with natural processes. More specifically, the project studies a) the mechanisms of biological and ecological response to stressors such as metal contamination, nutrient enrichment, physical habitat alteration, climate change, and introduced species, and b) the influence of species, communities, and ecosystem processes on the distribution, transport, and fate of chemical contaminants (e.g., metals, nutrients). Most studies...
The objectives are to 1) Quantify the hydrogeomorphic and ecological controls of nutrient and contaminant fluxes in wetland ecosystems; 2) Scale wetland fluxes from site to watershed scale; and 3) Identify the principals and modeling tools for managing wetland and river ecosystems. The focus will be on floodplain ecosystems, which are poorly studied due to the challenges of working in this environment and their inherent complexity.
Climate displays an often-unrecognized order in both time and space. What may appear as a random sequence of precipitation at a point or within a watershed is actually the local expression of a broad integrated system of weather processes that are active on scales of 100’s to 1000’s of kilometers. Only when climate forcings and hydrologic responses are considered from a regional perspective does the order become evident. Understanding these regional processes provides a sound basis for national, regional, and local hydrologic analysis, resource management, and hazard assessment/mitigation. The objectives of this research are (1) to identify and quantify relations between large-scale atmospheric circulation and sea-surface...
Human activities from climate change to waste discharges to water management are modifying ecosystems across the earth, often in ways that are not well understood. This project addresses the problem of better understanding changes in aquatic ecosystems as driven by human disturbances interacting with natural processes. More specifically, the project studies a) the mechanisms of biological and ecological response to stressors such as metal contamination, nutrient enrichment, physical habitat alteration, climate change, and introduced species, and b) the influence of species, communities, and ecosystem processes on the distribution, transport, and fate of chemical contaminants (e.g., metals, nutrients). Most studies...
Predicting the outcome of flow and sediment transport events quantitatively has been difficult due to the complex nature of stream systems and the effects of woody vegetation on flow and sediment transport. Interactions between channel and floodplain flow, sediment transport, and woody vegetation have important implications for the health of riparian vegetation and as well as for contaminant transport and deposition. The goal of my research is to develop methods for the application and testing of predictive, process-based models (no empirically adjusted coefficients) that compute the flow and sediment transport from fluid mechanical theory for (1) known channel and floodplain topography and (2) measured tree and...
Recent increases in the atmospheric concentrations of carbon dioxide and methane have emphasized the need for a more complete understanding of the processes that control carbon transfer among air, land, and water. Knowledge of the amount, rate and chemical form of carbon transfer across environmental interfaces, such as the land-air and water-air interfaces, is of particular importance. These fluxes are commonly controlled by a combination of physical, biological, and chemical processes at or near the interface. Isolation of the primary mechanisms that determine carbon transfer across the interface allows for development of process-based models that can be used for carbon mass transfer estimates at the ecosystem...
Uncertainty in application of physically based surface-water hydrologic models is a function of adequacy of the conceptualization of the processes involved and of the quantity and quality of data available to use as input to the model. In any type of modeling exercise, even if the physical processes are well understood, spatial heterogeneities make application of the model on a basin-wide scale problematic, and it is almost always necessary to use some form of spatial averaging to obtain 'effective' input variables. The over-all goal of our research is to investigate: (1) Model output errors as a function of model complexity and uncertainty in model input, (2) Derivation of simplified yet physically based models...
Project research is focused on two general objectives: first, to better understand the basic physics of coupled flow and sediment transport in geophysical flows; second, to develop practical tools based on that understanding that can be used in a predictive manner to aid in the management of the Nation’s rivers. Within the context of this overarching pair of long-term goals, the project has a number of specific shorter-term objectives, some of which are research oriented, and others of which are related to technology transfer or consultation on specific riverine issues. Our current research objectives are as follows: 1) Develop and test physically based methods for predicting the initiation, development, and response...
Sediment moves through a river system in response to specific events and changing conditions in the drainage basin. The movement of sediment is usually discontinuous. Episodes of movement are separated by periods of storage that can range from less than a year to more than one thousand. Understanding the movement and storage of sediment in rivers is important to navigation, flood control, and other aspects of river engineering, as well as to the prediction of the fate of contaminants adsorbed on sediment particles. This project's objectives are to assess: (1) changes in river sediment loads over periods of decades or longer, and the factors (natural or artificial) that cause the changes; (2) rates at which sediment...
My primary objective is to characterize the hydrology and water chemistry of watersheds and how they are affected by both natural factors and disturbance. I study the role of precipitation type, intensity, and spatial distribution in driving runoff and transport of sediment, carbon, nutrients, and major ions in both disturbed and undisturbed sites. My research incorporates field research and existing climate, hydrologic, and water-quality data to distinguish between the roles of climate, land-cover change, and disturbance in driving watershed processes. I strive to communicate research findings to scientists, regulators, and the public in order to support the management of water resources.


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