M. Alisa Mast
Alisa is an hydrologist for the Colorado Water Science Center
Science and Products
Filter Total Items: 70
A caveat regarding diatom-inferred nitrogen concentrations in oligotrophic lakes
Atmospheric deposition of reactive nitrogen (Nr) has enriched oligotrophic lakes with nitrogen (N) in many regions of the world and elicited dramatic changes in diatom community structure. The lakewater concentrations of nitrate that cause these community changes remain unclear, raising interest in the development of diatom-based transfer functions to infer nitrate. We developed a diatom calibrati
Authors
Heather A. Arnett, Jasmine E. Saros, Alisa Mast
Response of lake chemistry to changes in atmospheric deposition and climate in three high-elevation wilderness areas of Colorado
Trends in precipitation chemistry and hydrologic and climatic data were examined as drivers of long-term changes in the chemical composition of high-elevation lakes in three wilderness areas in Colorado during 1985–2008. Sulfate concentrations in precipitation decreased at a rate of −0.15 to −0.55 μeq/l/year at 10 high-elevation National Atmospheric Deposition Program stations in the state during
Authors
Alisa Mast, John T. Turk, David W. Clow, Donald D. Campbell
Spring runoff water-chemistry data from the Standard Mine and Elk Creek, Gunnison County, Colorado, 2010
Water samples were collected approximately every two weeks during the spring of 2010 from the Level 1 portal of the Standard Mine and from two locations on Elk Creek. The objective of the sampling was to: (1) better define the expected range and timing of variations in pH and metal concentrations in Level 1 discharge and Elk Creek during spring runoff; and (2) further evaluate possible mechanisms
Authors
Andrew H. Manning, Philip L. Verplanck, Alisa Mast, Joseph Marsik, R. Blaine McCleskey
Rocky Mountain snowpack physical and chemical data for selected sites, 2010
The Rocky Mountain Snowpack program established a network of snowpack-sampling sites in the Rocky Mountain region, from New Mexico to Montana, to monitor the chemical content of snow and to understand the effects of regional atmospheric deposition on freshwater systems. Scientists with the U.S. Geological Survey, in cooperation with the National Park Service; the U.S. Department of Agriculture For
Authors
George P. Ingersoll, Alisa Mast, James M. Swank, Chelsea D. Campbell
Trends in lake chemistry in response to atmospheric deposition and climate in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming, 1993-2009
In 2010, the U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, began a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. The purpose of this report is to describe trends in the chemical composition
Authors
Alisa Mast, George P. Ingersoll
Response of lake chemistry to atmospheric deposition and climate in selected Class I wilderness areas in the western United States, 1993-2009
The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, conducted a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. Understanding how and why lake chemistry is changing in mountain areas is essenti
Authors
Alisa Mast
Potential climate change effects on water tables and pyrite oxidation in headwater catchments in Colorado
A water, energy, and biogeochemical model (WEBMOD) was constructed to simulate hydrology and pyrite oxidation for the period October 1992 through September 1997. The hydrologic model simulates processes in Loch Vale, a 6.6-km² granitic watershed that drains the east side of the Continental Divide. Parameters describing pyrite oxidation were derived sulfate concentrations measured in pore water and
Authors
Richard M. Webb, Alisa Mast, Andrew H. Manning, David W. Clow, Donald H. Campbell
Rocky Mountain snowpack physical and chemical data for selected sites, 2009
The Rocky Mountain Snowpack program established a network of snowpack-sampling sites in the Rocky Mountain region from New Mexico to Montana to monitor the chemical content of snow and to understand the effects of regional atmospheric deposition. The U.S. Geological Survey, in cooperation with the National Park Service; the U.S. Department of Agriculture Forest Service; the Colorado Department of
Authors
George P. Ingersoll, Alisa Mast, James M. Swank, Chelsea D. Campbell
Comparison of mercury in water, bottom sediment, and zooplankton in two Front Range reservoirs in Colorado, 2008-09
The U.S. Geological Survey, in cooperation with the Colorado Department of Public Health and Environment, conducted a study to investigate environmental factors that may contribute to the bioaccumulation of mercury in two Front Range reservoirs. One of the reservoirs, Brush Hollow Reservoir, currently (2009) has a fish-consumption advisory for mercury in walleye (Stizostedion vitreum), and the oth
Authors
Alisa Mast, David P. Krabbenhoft
Mechanisms for chemostatic behavior in catchments: implications for CO2 consumption by mineral weathering
Concentrations of weathering products in streams often show relatively little variation compared to changes in discharge, both at event and annual scales. In this study, several hypothesized mechanisms for this “chemostatic behavior” were evaluated, and the potential for those mechanisms to influence relations between climate, weathering fluxes, and CO2 consumption via mineral weathering was asses
Authors
David W. Clow, Alisa Mast
Historical deposition of mercury and selected trace elements to high-elevation National Parks in the Western U.S. inferred from lake-sediment cores
Atmospheric deposition of Hg and selected trace elements was reconstructed over the past 150 years using sediment cores collected from nine remote, high-elevation lakes in Rocky Mountain National Park in Colorado and Glacier National Park in Montana. Cores were age dated by 210Pb, and sedimentation rates were determined using the constant rate of supply model. Hg concentrations in most of the core
Authors
Alisa Mast, David J. Manthorne, David A. Roth
Rocky Mountain Snowpack Physical and Chemical Data for Selected Sites, 1993-2008
The Rocky Mountain Snowpack program established a network of snowpack-sampling sites in the Rocky Mountain region from New Mexico to Montana to monitor the chemical content of snow to help in the understanding of the effects of atmospheric deposition to this region. The U.S. Geological Survey, in cooperation with the National Park Service, the USDA Forest Service, Teton County in Wyoming, Rio Blan
Authors
George P. Ingersoll, Alisa Mast, Donald H. Campbell, David W. Clow, Leora Nanus, John T. Turk
Science and Products
Filter Total Items: 70
A caveat regarding diatom-inferred nitrogen concentrations in oligotrophic lakes
Atmospheric deposition of reactive nitrogen (Nr) has enriched oligotrophic lakes with nitrogen (N) in many regions of the world and elicited dramatic changes in diatom community structure. The lakewater concentrations of nitrate that cause these community changes remain unclear, raising interest in the development of diatom-based transfer functions to infer nitrate. We developed a diatom calibrati
Authors
Heather A. Arnett, Jasmine E. Saros, Alisa Mast
Response of lake chemistry to changes in atmospheric deposition and climate in three high-elevation wilderness areas of Colorado
Trends in precipitation chemistry and hydrologic and climatic data were examined as drivers of long-term changes in the chemical composition of high-elevation lakes in three wilderness areas in Colorado during 1985–2008. Sulfate concentrations in precipitation decreased at a rate of −0.15 to −0.55 μeq/l/year at 10 high-elevation National Atmospheric Deposition Program stations in the state during
Authors
Alisa Mast, John T. Turk, David W. Clow, Donald D. Campbell
Spring runoff water-chemistry data from the Standard Mine and Elk Creek, Gunnison County, Colorado, 2010
Water samples were collected approximately every two weeks during the spring of 2010 from the Level 1 portal of the Standard Mine and from two locations on Elk Creek. The objective of the sampling was to: (1) better define the expected range and timing of variations in pH and metal concentrations in Level 1 discharge and Elk Creek during spring runoff; and (2) further evaluate possible mechanisms
Authors
Andrew H. Manning, Philip L. Verplanck, Alisa Mast, Joseph Marsik, R. Blaine McCleskey
Rocky Mountain snowpack physical and chemical data for selected sites, 2010
The Rocky Mountain Snowpack program established a network of snowpack-sampling sites in the Rocky Mountain region, from New Mexico to Montana, to monitor the chemical content of snow and to understand the effects of regional atmospheric deposition on freshwater systems. Scientists with the U.S. Geological Survey, in cooperation with the National Park Service; the U.S. Department of Agriculture For
Authors
George P. Ingersoll, Alisa Mast, James M. Swank, Chelsea D. Campbell
Trends in lake chemistry in response to atmospheric deposition and climate in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming, 1993-2009
In 2010, the U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, began a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. The purpose of this report is to describe trends in the chemical composition
Authors
Alisa Mast, George P. Ingersoll
Response of lake chemistry to atmospheric deposition and climate in selected Class I wilderness areas in the western United States, 1993-2009
The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, conducted a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. Understanding how and why lake chemistry is changing in mountain areas is essenti
Authors
Alisa Mast
Potential climate change effects on water tables and pyrite oxidation in headwater catchments in Colorado
A water, energy, and biogeochemical model (WEBMOD) was constructed to simulate hydrology and pyrite oxidation for the period October 1992 through September 1997. The hydrologic model simulates processes in Loch Vale, a 6.6-km² granitic watershed that drains the east side of the Continental Divide. Parameters describing pyrite oxidation were derived sulfate concentrations measured in pore water and
Authors
Richard M. Webb, Alisa Mast, Andrew H. Manning, David W. Clow, Donald H. Campbell
Rocky Mountain snowpack physical and chemical data for selected sites, 2009
The Rocky Mountain Snowpack program established a network of snowpack-sampling sites in the Rocky Mountain region from New Mexico to Montana to monitor the chemical content of snow and to understand the effects of regional atmospheric deposition. The U.S. Geological Survey, in cooperation with the National Park Service; the U.S. Department of Agriculture Forest Service; the Colorado Department of
Authors
George P. Ingersoll, Alisa Mast, James M. Swank, Chelsea D. Campbell
Comparison of mercury in water, bottom sediment, and zooplankton in two Front Range reservoirs in Colorado, 2008-09
The U.S. Geological Survey, in cooperation with the Colorado Department of Public Health and Environment, conducted a study to investigate environmental factors that may contribute to the bioaccumulation of mercury in two Front Range reservoirs. One of the reservoirs, Brush Hollow Reservoir, currently (2009) has a fish-consumption advisory for mercury in walleye (Stizostedion vitreum), and the oth
Authors
Alisa Mast, David P. Krabbenhoft
Mechanisms for chemostatic behavior in catchments: implications for CO2 consumption by mineral weathering
Concentrations of weathering products in streams often show relatively little variation compared to changes in discharge, both at event and annual scales. In this study, several hypothesized mechanisms for this “chemostatic behavior” were evaluated, and the potential for those mechanisms to influence relations between climate, weathering fluxes, and CO2 consumption via mineral weathering was asses
Authors
David W. Clow, Alisa Mast
Historical deposition of mercury and selected trace elements to high-elevation National Parks in the Western U.S. inferred from lake-sediment cores
Atmospheric deposition of Hg and selected trace elements was reconstructed over the past 150 years using sediment cores collected from nine remote, high-elevation lakes in Rocky Mountain National Park in Colorado and Glacier National Park in Montana. Cores were age dated by 210Pb, and sedimentation rates were determined using the constant rate of supply model. Hg concentrations in most of the core
Authors
Alisa Mast, David J. Manthorne, David A. Roth
Rocky Mountain Snowpack Physical and Chemical Data for Selected Sites, 1993-2008
The Rocky Mountain Snowpack program established a network of snowpack-sampling sites in the Rocky Mountain region from New Mexico to Montana to monitor the chemical content of snow to help in the understanding of the effects of atmospheric deposition to this region. The U.S. Geological Survey, in cooperation with the National Park Service, the USDA Forest Service, Teton County in Wyoming, Rio Blan
Authors
George P. Ingersoll, Alisa Mast, Donald H. Campbell, David W. Clow, Leora Nanus, John T. Turk