USGS initiated the Water, Energy, and Biogeochemical Budgets (WEBB) program to understand the processes controlling water, energy, and biogeochemical fluxes over a range of temporal and spatial scales, and the effects of atmospheric and climatic variables. Trout Lake is one of five small, geographically and ecologically diverse watersheds representing a range of hydrologic and climatic conditions.
SITE DESCRIPTION
The Trout Lake WEBB site is in the Northern Highland area of north-central Wisconsin. The site includes five open lakes and two bog lakes. It is also the site of the NSF-sponsored North Temperate Lakes Long-Term Ecological Research (NTL/LTER) project, which has been ongoing since 1980 under the direction of the Center for Limnology, University of Wisconsin-Madison. The WEBB hydrologic and biogeochemical research in the LTER lake watersheds complements the ecological research conducted at the NTL/LTER, which is focused on in-lake processes. In this sparsely populated area, many lakes have totally forested watersheds and no private frontage.
Geologic features of the area are dominated by a sandy outwash plain consisting of 30 to 50 meters of unconsolidated sand and coarser till overlying Precambrian igneous bedrock. The predominant soils are thin forest soils with high organic content in the uppermost horizon. The site is representative of the glacial lake districts common to the upper Midwest and Canada, but certain individual characteristics distinguish it from other nearby lake areas. Among the most important of these characteristics is glacial drift that is virtually carbonate free; as a result, the ground-water chemistry is almost entirely controlled by silicate hydrolysis.
Most of the lakes in the Northern Highland area are seepage lakes--they have no surface-water inlets or outlets. Water budgets are thus dominated by direct precipitation, ground-water flow, and evapotranspiration. The seven study lakes, four of which are seepage lakes, are all in the same ground-water-flow system. Lakes in topographic highs, such as the two bog lakes and Crystal Lake, receive little ground-water flow and no streamflow and have water with low ionic concentrations (10 to 20 microSiemens per centimeter, mS/cm). Lakes in topographic lows, such as Trout Lake, are dominated by ground-water and stream inputs and have water with higher ionic concentrations (70 to 90 mS/cm). Although linked by a common ground-water-flow system and similar climate, the lakes represent a broad range of size, morphometry, habitat, thermal features, chemistry, biological productivity, and species composition.
RESEARCH AREAS
Rainfall, Streamflow, and Recharge Processes
Objectives:
- Investigate the processes controlling streamflow generation in response to rainfall for low-relief hydrologic settings.
- Investigate the processes that lead to ground-water recharge in the TL basin.
- Develop appropriate predictive capabilities for the identified streamflow-generation and ground-water-recharge processes.
- Investigate the implications of increases in spatial and temporal scale on the predictive capabilities.
Approach:
- Use stable isotopes of water (oxygen-18 and deuterium) to identify streamflow-generation mechanisms by examining the isotopic evolution of water as in moves through the hydrologic system. Three detailed hillslope sites along Allequash Creek are instrumented with nested piezometers, lysimeters and bulk rainfall and throughfall collectors.
Groundwater/Surface Water Interactions
Objectives:
- Determine the water and solute yields for the Trout Lake Basin and determine the relative importance of streamflow to the water and solute budgets for Trout Lake.
- Identify the geochemical processes that control the flux of major chemical species (such as nitrogen and sulfur species) at the aquifer-lake and aquifer-stream interfaces, and the temporal and spatial variability of these processes.
Approach:
- Streams tributary to Trout Lake are sampled periodically to allow the computation of solute fluxes from streams into and out of Trout Lake. The samples are analyzed for nutrients and major ions. The importance of surface-water sources to the complete hydrologic and chemical budget of Trout Lake is being determined from the estimated surface-water fluxes and the existing NTL/LTER data base.
- Processes that control the mass flux of chemical species across the stream interface are being identified by means of fine-scale sampling (that is, less than 1 centimeter, cm). The samples are collected at various times of the year at two locations along Allequash Creek. Samples are also collected periodically from a detailed transect along Allequash Creek to determine larger-scale variations.
Carbon Flux Processes
Objectives:
- Identify the processes that control the flux of major carbon species (such as dissolved inorganic carbon, dissolved organic carbon, carbon dioxide and methane) within the Allequash Creek watershed, and the temporal and spatial variability of these processes.
Approach:
- Carbon fluxes are being estimated through periodoc sampling of various system components (see carbon flux schematic for details), and measured directly for soil effux using soil chambers. A variety of land cover and slope/aspect combinations are being sampled to help pinpoint the spatial variability.
Below are publications associated with this project.
Simulating the effect of climate change on stream temperature in the Trout Lake Watershed, Wisconsin
Integrated watershed-scale response to climate change for selected basins across the United States
MODFLOW-style parameters in underdetermined parameter estimation
Approaches to highly parameterized inversion: Pilot-point theory, guidelines, and research directions
Characterizing climate-change impacts on the 1.5-yr flood flow in selected basins across the United States: a probabilistic approach
Approaches to highly parameterized inversion-A guide to using PEST for groundwater-model calibration
Using a cloud to replenish parched groundwater modeling efforts
Approaches to highly parameterized inversion: A guide to using PEST for model-parameter and predictive-uncertainty analysis
On constraining pilot point calibration with regularization in PEST
Two statistics for evaluating parameter identifiability and error reduction
Obtaining parsimonious hydraulic conductivity fields using head and transport observations: A Bayesian geostatistical parameter estimation approach
Using a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, northern Wisconsin
Below are news stories associated with this project.
Below are partners associated with this project.
- Overview
USGS initiated the Water, Energy, and Biogeochemical Budgets (WEBB) program to understand the processes controlling water, energy, and biogeochemical fluxes over a range of temporal and spatial scales, and the effects of atmospheric and climatic variables. Trout Lake is one of five small, geographically and ecologically diverse watersheds representing a range of hydrologic and climatic conditions.
SITE DESCRIPTION
The Trout Lake WEBB site is in the Northern Highland area of north-central Wisconsin. The site includes five open lakes and two bog lakes. It is also the site of the NSF-sponsored North Temperate Lakes Long-Term Ecological Research (NTL/LTER) project, which has been ongoing since 1980 under the direction of the Center for Limnology, University of Wisconsin-Madison. The WEBB hydrologic and biogeochemical research in the LTER lake watersheds complements the ecological research conducted at the NTL/LTER, which is focused on in-lake processes. In this sparsely populated area, many lakes have totally forested watersheds and no private frontage.
Geologic features of the area are dominated by a sandy outwash plain consisting of 30 to 50 meters of unconsolidated sand and coarser till overlying Precambrian igneous bedrock. The predominant soils are thin forest soils with high organic content in the uppermost horizon. The site is representative of the glacial lake districts common to the upper Midwest and Canada, but certain individual characteristics distinguish it from other nearby lake areas. Among the most important of these characteristics is glacial drift that is virtually carbonate free; as a result, the ground-water chemistry is almost entirely controlled by silicate hydrolysis.
Most of the lakes in the Northern Highland area are seepage lakes--they have no surface-water inlets or outlets. Water budgets are thus dominated by direct precipitation, ground-water flow, and evapotranspiration. The seven study lakes, four of which are seepage lakes, are all in the same ground-water-flow system. Lakes in topographic highs, such as the two bog lakes and Crystal Lake, receive little ground-water flow and no streamflow and have water with low ionic concentrations (10 to 20 microSiemens per centimeter, mS/cm). Lakes in topographic lows, such as Trout Lake, are dominated by ground-water and stream inputs and have water with higher ionic concentrations (70 to 90 mS/cm). Although linked by a common ground-water-flow system and similar climate, the lakes represent a broad range of size, morphometry, habitat, thermal features, chemistry, biological productivity, and species composition.
RESEARCH AREAS
Middle Allequash stream site in winter, 2003 Rainfall, Streamflow, and Recharge Processes
Objectives:
- Investigate the processes controlling streamflow generation in response to rainfall for low-relief hydrologic settings.
- Investigate the processes that lead to ground-water recharge in the TL basin.
- Develop appropriate predictive capabilities for the identified streamflow-generation and ground-water-recharge processes.
- Investigate the implications of increases in spatial and temporal scale on the predictive capabilities.
Approach:
- Use stable isotopes of water (oxygen-18 and deuterium) to identify streamflow-generation mechanisms by examining the isotopic evolution of water as in moves through the hydrologic system. Three detailed hillslope sites along Allequash Creek are instrumented with nested piezometers, lysimeters and bulk rainfall and throughfall collectors.
Groundwater/Surface Water Interactions
Objectives:
- Determine the water and solute yields for the Trout Lake Basin and determine the relative importance of streamflow to the water and solute budgets for Trout Lake.
- Identify the geochemical processes that control the flux of major chemical species (such as nitrogen and sulfur species) at the aquifer-lake and aquifer-stream interfaces, and the temporal and spatial variability of these processes.
Approach:
- Streams tributary to Trout Lake are sampled periodically to allow the computation of solute fluxes from streams into and out of Trout Lake. The samples are analyzed for nutrients and major ions. The importance of surface-water sources to the complete hydrologic and chemical budget of Trout Lake is being determined from the estimated surface-water fluxes and the existing NTL/LTER data base.
- Processes that control the mass flux of chemical species across the stream interface are being identified by means of fine-scale sampling (that is, less than 1 centimeter, cm). The samples are collected at various times of the year at two locations along Allequash Creek. Samples are also collected periodically from a detailed transect along Allequash Creek to determine larger-scale variations.
Carbon Flux Processes
Objectives:
- Identify the processes that control the flux of major carbon species (such as dissolved inorganic carbon, dissolved organic carbon, carbon dioxide and methane) within the Allequash Creek watershed, and the temporal and spatial variability of these processes.
Approach:
- Carbon fluxes are being estimated through periodoc sampling of various system components (see carbon flux schematic for details), and measured directly for soil effux using soil chambers. A variety of land cover and slope/aspect combinations are being sampled to help pinpoint the spatial variability.
- Publications
Below are publications associated with this project.
Filter Total Items: 32Simulating the effect of climate change on stream temperature in the Trout Lake Watershed, Wisconsin
The potential for increases in stream temperature across many spatial and temporal scales as a result of climate change can pose a difficult challenge for environmental managers, especially when addressing thermal requirements for sensitive aquatic species. This study evaluates simulated changes to the thermal regime of three northern Wisconsin streams in response to a projected changing climate uAuthorsWilliam R. SelbigIntegrated watershed-scale response to climate change for selected basins across the United States
A study by the U.S. Geological Survey (USGS) evaluated the hydrologic response to different projected carbon emission scenarios of the 21st century using a hydrologic simulation model. This study involved five major steps: (1) setup, calibrate and evaluated the Precipitation Runoff Modeling System (PRMS) model in 14 basins across the United States by local USGS personnel; (2) acquire selected simuAuthorsSteven L. Markstrom, Lauren E. Hay, D. Christian Ward-Garrison, John C. Risley, William A. Battaglin, David M. Bjerklie, Katherine J. Chase, Daniel E. Christiansen, Robert W. Dudley, Randall J. Hunt, Kathryn M. Koczot, Mark C. Mastin, R. Steven Regan, Roland J. Viger, Kevin C. Vining, John F. WalkerMODFLOW-style parameters in underdetermined parameter estimation
In this article, we discuss the use of MODFLOW-Style parameters in the numerical codes MODFLOW_2005 and MODFLOW_2005-Adjoint for the definition of variables in the Layer Property Flow package. Parameters are a useful tool to represent aquifer properties in both codes and are the only option available in the adjoint version. Moreover, for overdetermined parameter estimation problems, the parameterAuthorsMarco D. D'Oria, Michael N. FienenApproaches to highly parameterized inversion: Pilot-point theory, guidelines, and research directions
Pilot points have been used in geophysics and hydrogeology for at least 30 years as a means to bridge the gap between estimating a parameter value in every cell of a model and subdividing models into a small number of homogeneous zones. Pilot points serve as surrogate parameters at which values are estimated in the inverse-modeling process, and their values are interpolated onto the modeling domaiAuthorsJohn E. Doherty, Michael N. Fienen, Randall J. HuntCharacterizing climate-change impacts on the 1.5-yr flood flow in selected basins across the United States: a probabilistic approach
The U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) model was applied to basins in 14 different hydroclimatic regions to determine the sensitivity and variability of the freshwater resources of the United States in the face of current climate-change projections. Rather than attempting to choose a most likely scenario from the results of the Intergovernmental Panel on Climate ChaAuthorsJohn F. Walker, Lauren E. Hay, Steven L. Markstrom, Michael D. DettingerApproaches to highly parameterized inversion-A guide to using PEST for groundwater-model calibration
Highly parameterized groundwater models can create calibration difficulties. Regularized inversion-the combined use of large numbers of parameters with mathematical approaches for stable parameter estimation-is becoming a common approach to address these difficulties and enhance the transfer of information contained in field measurements to parameters used to model that system. Though commonly useAuthorsJohn E. Doherty, Randall J. HuntUsing a cloud to replenish parched groundwater modeling efforts
Groundwater models can be improved by introduction of additional parameter flexibility and simultaneous use of soft-knowledge. However, these sophisticated approaches have high computational requirements. Cloud computing provides unprecedented access to computing power via the Internet to facilitate the use of these techniques. A modeler can create, launch, and terminate “virtual” computers as neeAuthorsRandall J. Hunt, Joseph Luchette, Willem A. Schreuder, James O. Rumbaugh, John Doherty, Matthew J. Tonkin, Douglas B. RumbaughApproaches to highly parameterized inversion: A guide to using PEST for model-parameter and predictive-uncertainty analysis
Analysis of the uncertainty associated with parameters used by a numerical model, and with predictions that depend on those parameters, is fundamental to the use of modeling in support of decisionmaking. Unfortunately, predictive uncertainty analysis with regard to models can be very computationally demanding, due in part to complex constraints on parameters that arise from expert knowledge of sysAuthorsJohn E. Doherty, Randall J. Hunt, Matthew J. TonkinOn constraining pilot point calibration with regularization in PEST
Ground water model calibration has made great advances in recent years with practical tools such as PEST being instrumental for making the latest techniques available to practitioners. As models and calibration tools get more sophisticated, however, the power of these tools can be misapplied, resulting in poor parameter estimates and/or nonoptimally calibrated models that do not suit their intendeAuthorsM.N. Fienen, C.T. Muffels, R. J. HuntTwo statistics for evaluating parameter identifiability and error reduction
Two statistics are presented that can be used to rank input parameters utilized by a model in terms of their relative identifiability based on a given or possible future calibration dataset. Identifiability is defined here as the capability of model calibration to constrain parameters used by a model. Both statistics require that the sensitivity of each model parameter be calculated for each modelAuthorsJohn Doherty, Randall J. HuntObtaining parsimonious hydraulic conductivity fields using head and transport observations: A Bayesian geostatistical parameter estimation approach
Flow path delineation is a valuable tool for interpreting the subsurface hydrogeochemical environment. Different types of data, such as groundwater flow and transport, inform different aspects of hydrogeologic parameter values (hydraulic conductivity in this case) which, in turn, determine flow paths. This work combines flow and transport information to estimate a unified set of hydrogeologic paraAuthorsMichael N. Fienen, R. Hunt, D. Krabbenhoft, T. ClemoUsing a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, northern Wisconsin
A major focus of the U.S. Geological Survey’s Trout Lake Water, Energy, and Biogeochemical Budgets (WEBB) project is the development of a watershed model to allow predictions of hydrologic response to future conditions including land-use and climate change. The coupled groundwater/surface-water model GSFLOW was chosen for this purpose because it could easily incorporate an existing groundwater floAuthorsRandall J. Hunt, John F. Walker, Steven L. Markstrom, Lauren E. Hay, John Doherty - News
Below are news stories associated with this project.
- Partners
Below are partners associated with this project.