M. Alisa Mast (Former Employee)
Science and Products
Filter Total Items: 96
Mercury transport in a high-elevation watershed in Rocky Mountain National Park, Colorado Mercury transport in a high-elevation watershed in Rocky Mountain National Park, Colorado
Mercury (Hg) was measured in stream water and precipitation in the Loch Vale watershed in Rocky Mountain National Park, Colorado, during 2001–2002 to investigate processes controlling Hg transport in high-elevation ecosystems. Total Hg concentrations in precipitation ranged from 2.6 to 36.2 ng/L and showed a strong seasonal pattern with concentrations that were 3 to 4 times higher during...
Authors
M.A. Mast, K. Campbell, D. P. Krabbenhoft, Howard E. Taylor
The U.S. Geological Survey Hydrologic Benchmark Network The U.S. Geological Survey Hydrologic Benchmark Network
No abstract available.
Authors
Peter S. Murdoch, Michael R. McHale, M. Alisa Mast, David W. Clow
Rocky Mountain Snowpack Chemistry at Selected Sites, 2002 Rocky Mountain Snowpack Chemistry at Selected Sites, 2002
During spring 2002, the chemical composition of annual snowpacks in the Rocky Mountain region of the Western United States was analyzed. Snow samples were collected at 75 geographically distributed sites extending from New Mexico to Montana. Near the end of the 2002 snowfall season, the snow-water equivalent (SWE) in annual snowpacks sampled generally was below average in most of the...
Authors
George P. Ingersoll, M. Alisa Mast, Leora Nanus, David J. Manthorne, David W. Clow, Heather M. Handran, Jesse A. Winterringer, Donald H. Campbell
Atmospheric deposition of nutrients, pesticides, and mercury in Rocky Mountain National Park, Colorado, 2002 Atmospheric deposition of nutrients, pesticides, and mercury in Rocky Mountain National Park, Colorado, 2002
Nutrients, current-use pesticides, and mercury were measured in atmospheric deposition during summer in Rocky Mountain National Park in Colorado to improve understanding of the type and magnitude of atmospheric contaminants being deposited in the park. Two deposition sites were established on the east side of the park: one at an elevation of 2,902 meters near Bear Lake for nutrients and...
Authors
M. Alisa Mast, Donald H. Campbell, George P. Ingersoll, William T. Foreman, David P. Krabbenhoft
Rocky Mountain snowpack chemistry at selected sites for 2001 Rocky Mountain snowpack chemistry at selected sites for 2001
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants...
Authors
George P. Ingersoll, M. Alisa Mast, David W. Clow, Leora Nanus, Donald H. Campbell, Heather Handran
Using water-quality profiles to characterize seasonal water quality and loading in the upper Animas River basin, southwestern Colorado Using water-quality profiles to characterize seasonal water quality and loading in the upper Animas River basin, southwestern Colorado
One of the important types of information needed to characterize water quality in streams affected by historical mining is the seasonal pattern of toxic trace-metal concentrations and loads. Seasonal patterns in water quality are estimated in this report using a technique called water-quality profiling. Water-quality profiling allows land managers and scientists to assess priority areas...
Authors
Kenneth J. Leib, M. Alisa Mast, Winfield G. Wright
Atmospheric deposition maps for the Rocky Mountains Atmospheric deposition maps for the Rocky Mountains
Variability in atmospheric deposition across the Rocky Mountains is influenced by elevation, slope, aspect, and precipitation amount and by regional and local sources of air pollution. To improve estimates of deposition in mountainous regions, maps of average annual atmospheric deposition loadings of nitrate, sulfate, and acidity were developed for the Rocky Mountains by using spatial...
Authors
L. Nanus, K. Campbell, G.P. Ingersoll, D. W. Clow, M.A. Mast
Chemistry of selected high-elevation lakes in seven national parks in the western United States Chemistry of selected high-elevation lakes in seven national parks in the western United States
A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky...
Authors
David W. Clow, Robert G. Striegl, Leora Nanus, M. Alisa Mast, Donald H. Campbell, David P. Krabbenhoft
Use of natural 35S to trace sulphate cycling in small lakes, Flattops Wilderness Area, Colorado, U.S.A. Use of natural 35S to trace sulphate cycling in small lakes, Flattops Wilderness Area, Colorado, U.S.A.
Measurements of the cosmogenically-produced 35S, a radioisotope of sulphur (t1/2 = 87 days), are reported for the Ned Wilson Lake watershed in Colorado. The watershed contains two small lakes and a flowing spring presumed to be representative of local ground water. The watershed is located in the Flattops Wilderness Area and the waters in the system have low alkalinity, making them...
Authors
Robert L. Michel, John T. Turk, Donald H. Campbell, M. Alisa Mast
Rocky Mountain snowpack chemistry network: History, methods, and the importance of monitoring mountain ecosystems Rocky Mountain snowpack chemistry network: History, methods, and the importance of monitoring mountain ecosystems
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey to more thoroughly determine the quality of precipitation and to identify sources of atmospherically deposited pollution in a network of high-elevation sites. Depth-integrated samples of seasonal snowpacks at 52 sampling sites, in a network from New...
Authors
George P. Ingersoll, John T. Turk, M. Alisa Mast, David W. Clow, Donald H. Campbell, Zelda C. Bailey
Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition
Depth-integrated snowpack chemistry was measured just prior to maximum snowpack depth during the winters of 1992-1999 at 12 sites co-located with National Atmospheric Deposition Program/National Trend Network (NADP/NTN) sites in the central and southern Rocky Mountains, USA. Winter volume-weighted mean wet-deposition concentrations were calculated for the NADP/NTN sites, and the data...
Authors
David W. Clow, George P. Ingersoll, M. Alisa Mast, John T. Turk, Donald H. Campbell
Major-ion chemistry of the Rocky Mountain snowpack, USA Major-ion chemistry of the Rocky Mountain snowpack, USA
During 1993-97, samples of the full depth of the Rocky Mountain snowpack were collected at 52 sites from northern New Mexico to Montana and analyzed for major-ion concentrations. Concentrations of acidity, sulfate, nitrate, and calcium increased from north to south along the mountain range. In the northern part of the study area, acidity was most correlated (negatively) with calcium...
Authors
J.T. Turk, Howard E. Taylor, G.P. Ingersoll, K.A. Tonnessen, D. W. Clow, M.A. Mast, K. Campbell, J.M. Melack
Science and Products
Filter Total Items: 96
Mercury transport in a high-elevation watershed in Rocky Mountain National Park, Colorado Mercury transport in a high-elevation watershed in Rocky Mountain National Park, Colorado
Mercury (Hg) was measured in stream water and precipitation in the Loch Vale watershed in Rocky Mountain National Park, Colorado, during 2001–2002 to investigate processes controlling Hg transport in high-elevation ecosystems. Total Hg concentrations in precipitation ranged from 2.6 to 36.2 ng/L and showed a strong seasonal pattern with concentrations that were 3 to 4 times higher during...
Authors
M.A. Mast, K. Campbell, D. P. Krabbenhoft, Howard E. Taylor
The U.S. Geological Survey Hydrologic Benchmark Network The U.S. Geological Survey Hydrologic Benchmark Network
No abstract available.
Authors
Peter S. Murdoch, Michael R. McHale, M. Alisa Mast, David W. Clow
Rocky Mountain Snowpack Chemistry at Selected Sites, 2002 Rocky Mountain Snowpack Chemistry at Selected Sites, 2002
During spring 2002, the chemical composition of annual snowpacks in the Rocky Mountain region of the Western United States was analyzed. Snow samples were collected at 75 geographically distributed sites extending from New Mexico to Montana. Near the end of the 2002 snowfall season, the snow-water equivalent (SWE) in annual snowpacks sampled generally was below average in most of the...
Authors
George P. Ingersoll, M. Alisa Mast, Leora Nanus, David J. Manthorne, David W. Clow, Heather M. Handran, Jesse A. Winterringer, Donald H. Campbell
Atmospheric deposition of nutrients, pesticides, and mercury in Rocky Mountain National Park, Colorado, 2002 Atmospheric deposition of nutrients, pesticides, and mercury in Rocky Mountain National Park, Colorado, 2002
Nutrients, current-use pesticides, and mercury were measured in atmospheric deposition during summer in Rocky Mountain National Park in Colorado to improve understanding of the type and magnitude of atmospheric contaminants being deposited in the park. Two deposition sites were established on the east side of the park: one at an elevation of 2,902 meters near Bear Lake for nutrients and...
Authors
M. Alisa Mast, Donald H. Campbell, George P. Ingersoll, William T. Foreman, David P. Krabbenhoft
Rocky Mountain snowpack chemistry at selected sites for 2001 Rocky Mountain snowpack chemistry at selected sites for 2001
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants...
Authors
George P. Ingersoll, M. Alisa Mast, David W. Clow, Leora Nanus, Donald H. Campbell, Heather Handran
Using water-quality profiles to characterize seasonal water quality and loading in the upper Animas River basin, southwestern Colorado Using water-quality profiles to characterize seasonal water quality and loading in the upper Animas River basin, southwestern Colorado
One of the important types of information needed to characterize water quality in streams affected by historical mining is the seasonal pattern of toxic trace-metal concentrations and loads. Seasonal patterns in water quality are estimated in this report using a technique called water-quality profiling. Water-quality profiling allows land managers and scientists to assess priority areas...
Authors
Kenneth J. Leib, M. Alisa Mast, Winfield G. Wright
Atmospheric deposition maps for the Rocky Mountains Atmospheric deposition maps for the Rocky Mountains
Variability in atmospheric deposition across the Rocky Mountains is influenced by elevation, slope, aspect, and precipitation amount and by regional and local sources of air pollution. To improve estimates of deposition in mountainous regions, maps of average annual atmospheric deposition loadings of nitrate, sulfate, and acidity were developed for the Rocky Mountains by using spatial...
Authors
L. Nanus, K. Campbell, G.P. Ingersoll, D. W. Clow, M.A. Mast
Chemistry of selected high-elevation lakes in seven national parks in the western United States Chemistry of selected high-elevation lakes in seven national parks in the western United States
A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky...
Authors
David W. Clow, Robert G. Striegl, Leora Nanus, M. Alisa Mast, Donald H. Campbell, David P. Krabbenhoft
Use of natural 35S to trace sulphate cycling in small lakes, Flattops Wilderness Area, Colorado, U.S.A. Use of natural 35S to trace sulphate cycling in small lakes, Flattops Wilderness Area, Colorado, U.S.A.
Measurements of the cosmogenically-produced 35S, a radioisotope of sulphur (t1/2 = 87 days), are reported for the Ned Wilson Lake watershed in Colorado. The watershed contains two small lakes and a flowing spring presumed to be representative of local ground water. The watershed is located in the Flattops Wilderness Area and the waters in the system have low alkalinity, making them...
Authors
Robert L. Michel, John T. Turk, Donald H. Campbell, M. Alisa Mast
Rocky Mountain snowpack chemistry network: History, methods, and the importance of monitoring mountain ecosystems Rocky Mountain snowpack chemistry network: History, methods, and the importance of monitoring mountain ecosystems
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey to more thoroughly determine the quality of precipitation and to identify sources of atmospherically deposited pollution in a network of high-elevation sites. Depth-integrated samples of seasonal snowpacks at 52 sampling sites, in a network from New...
Authors
George P. Ingersoll, John T. Turk, M. Alisa Mast, David W. Clow, Donald H. Campbell, Zelda C. Bailey
Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition
Depth-integrated snowpack chemistry was measured just prior to maximum snowpack depth during the winters of 1992-1999 at 12 sites co-located with National Atmospheric Deposition Program/National Trend Network (NADP/NTN) sites in the central and southern Rocky Mountains, USA. Winter volume-weighted mean wet-deposition concentrations were calculated for the NADP/NTN sites, and the data...
Authors
David W. Clow, George P. Ingersoll, M. Alisa Mast, John T. Turk, Donald H. Campbell
Major-ion chemistry of the Rocky Mountain snowpack, USA Major-ion chemistry of the Rocky Mountain snowpack, USA
During 1993-97, samples of the full depth of the Rocky Mountain snowpack were collected at 52 sites from northern New Mexico to Montana and analyzed for major-ion concentrations. Concentrations of acidity, sulfate, nitrate, and calcium increased from north to south along the mountain range. In the northern part of the study area, acidity was most correlated (negatively) with calcium...
Authors
J.T. Turk, Howard E. Taylor, G.P. Ingersoll, K.A. Tonnessen, D. W. Clow, M.A. Mast, K. Campbell, J.M. Melack