Karen C. Rice, PhD (Former Employee)
Science and Products
Filter Total Items: 71
From headwaters to coast: Influence of human activities on water quality of the Potomac River Estuary
The natural aging process of Chesapeake Bay and its tributary estuaries has been accelerated by human activities around the shoreline and within the watershed, increasing sediment and nutrient loads delivered to the bay. Riverine nutrients cause algal growth in the bay leading to reductions in light penetration with consequent declines in sea grass growth, smothering of bottom-dwelling organisms,
Authors
Suzanne B. Bricker, Karen C. Rice, Owen P. Bricker
Stream water temperature limits occupancy of salamanders in mid-Atlantic protected areas
Stream ecosystems are particularly sensitive to urbanization, and tolerance of water-quality parameters is likely important to population persistence of stream salamanders. Forecasted climate and landscape changes may lead to significant changes in stream flow, chemical composition, and temperatures in coming decades. Protected areas where landscape alterations are minimized will therefore become
Authors
Evan H. Campbell Grant, Amber N. M. Wiewel, Karen C. Rice
Comparison of mineral weathering and biomass nutrient uptake in two small forested watersheds underlain by quartzite bedrock, Catoctin Mountain, Maryland, USA
To quantify chemical weathering and biological uptake, mass-balance calculations were performed on two small forested watersheds located in the Blue Ridge Physiographic Province in north-central Maryland, USA. Both watersheds, Bear Branch (BB) and Fishing Creek Tributary (FCT), are underlain by relatively unreactive quartzite bedrock. Such unreactive bedrock and associated low chemical-weathering
Authors
Karen C. Rice, Jason R. Price
Response to L. Land comment on Bricker, Rice, Bricker (2014) From Headwaters to Coast: Influence of human activities on water quality of the Potomac River Estuary. Aquatic Geochemistry 20: 291-324
Overabundance of nutrients is considered one of the top challenges to most populated coastal water bodies, including Chesapeake Bay (Executive Order 13508). As scientists, one of our responsibilities is to contribute to the discussion and evaluation of management actions that have the potential to decrease pollution with concomitant improvement of water quality. Results of our science should infor
Authors
Suzanne B. Bricker, Karen C. Rice, III Bricker
Synthesis and interpretation of surface-water quality and aquatic biota data collected in Shenandoah National Park, Virginia, 1979-2009
Shenandoah National Park in northern and central Virginia protects 777 square kilometers of mountain terrain in the Blue Ridge physiographic province and more than 90 streams containing diverse aquatic biota. Park managers and visitors are interested in the water quality of park streams and its ability to support healthy coldwater communities and species, such as the native brook trout (Salvelinus
Authors
John D. Jastram, Craig D. Snyder, Nathaniel P. Hitt, Karen C. Rice
Mass-balance modeling of mineral weathering rates and CO2 consumption in the forested, metabasaltic Hauver Branch watershed, Catoctin Mountain, Maryland, USA
Mineral weathering rates and a forest macronutrient uptake stoichiometry were determined for the forested, metabasaltic Hauver Branch watershed in north-central Maryland, USA. Previous studies of Hauver Branch have had an insufficient number of analytes to permit determination of rates of all the minerals involved in chemical weathering, including biomass. More equations in the mass-balance matrix
Authors
Karen C. Rice, Jason R. Price, David W. Szymanski
Spatial and temporal trends in runoff at long-term streamgages within and near the Chesapeake Bay Watershed
Long-term streamflow data within the Chesapeake Bay watershed and surrounding area were analyzed in an attempt to identify trends in streamflow. Data from 30 streamgages near and within the Chesapeake Bay watershed were selected from 1930 through 2010 for analysis. Streamflow data were converted to runoff and trend slopes in percent change per decade were calculated. Trend slopes for three runoff
Authors
Karen C. Rice, Robert M. Hirsch
Acidification of Earth: An assessment across mechanisms and scales
In this review article, anthropogenic activities that cause acidification of Earth’s air, waters, and soils are examined. Although there are many mechanisms of acidification, the focus is on the major ones, including emissions from combustion of fossil fuels and smelting of ores, mining of coal and metal ores, and application of nitrogen fertilizer to soils, by elucidating the underlying biogeoche
Authors
Karen C. Rice, Janet S. Herman
Evaluation of Bayesian estimation of a hidden continuous-time Markov chain model with application to threshold violation in water-quality indicators
Natural resource managers require information concerning the frequency, duration, and long-term probability of occurrence of water-quality indicator (WQI) violations of defined thresholds. The timing of these threshold crossings often is hidden from the observer, who is restricted to relatively infrequent observations. Here, a model for the hidden process is linked with a model for the observatio
Authors
Frank A. Deviney, Karen C. Rice, Donald E. Brown
Assessment of salinity intrusion in the James and Chickahominy Rivers as a result of simulated sea-level rise in Chesapeake Bay, East Coast, USA
Global sea level is rising, and the relative rate in the Chesapeake Bay region of the East Coast of the United States is greater than the worldwide rate. Sea-level rise can cause saline water to migrate upstream in estuaries and rivers, threatening freshwater habitat and drinking-water supplies. The effects of future sea-level rise on two tributaries of Chesapeake Bay, the James and Chickahominy (
Authors
Karen C. Rice, Bo Hong, Jian Shen
Simulated changes in salinity in the York and Chickahominy Rivers from projected sea-level rise in Chesapeake Bay
As a result of climate change and variability, sea level is rising throughout the world, but the rate along the east coast of the United States is higher than the global mean rate. The U.S. Geological Survey, in cooperation with the City of Newport News, Virginia, conducted a study to evaluate the effects of possible future sea-level rise on the salinity front in two tributaries to Chesapeake Bay,
Authors
Karen C. Rice, Mark Bennett, Jian Shen
The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005-2006
Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product aminomethylphosphonic aci
Authors
William A. Battaglin, Karen C. Rice, Michael J. Focazio, Sue Salmons, Robert X. Barry
Science and Products
Filter Total Items: 71
From headwaters to coast: Influence of human activities on water quality of the Potomac River Estuary
The natural aging process of Chesapeake Bay and its tributary estuaries has been accelerated by human activities around the shoreline and within the watershed, increasing sediment and nutrient loads delivered to the bay. Riverine nutrients cause algal growth in the bay leading to reductions in light penetration with consequent declines in sea grass growth, smothering of bottom-dwelling organisms,
Authors
Suzanne B. Bricker, Karen C. Rice, Owen P. Bricker
Stream water temperature limits occupancy of salamanders in mid-Atlantic protected areas
Stream ecosystems are particularly sensitive to urbanization, and tolerance of water-quality parameters is likely important to population persistence of stream salamanders. Forecasted climate and landscape changes may lead to significant changes in stream flow, chemical composition, and temperatures in coming decades. Protected areas where landscape alterations are minimized will therefore become
Authors
Evan H. Campbell Grant, Amber N. M. Wiewel, Karen C. Rice
Comparison of mineral weathering and biomass nutrient uptake in two small forested watersheds underlain by quartzite bedrock, Catoctin Mountain, Maryland, USA
To quantify chemical weathering and biological uptake, mass-balance calculations were performed on two small forested watersheds located in the Blue Ridge Physiographic Province in north-central Maryland, USA. Both watersheds, Bear Branch (BB) and Fishing Creek Tributary (FCT), are underlain by relatively unreactive quartzite bedrock. Such unreactive bedrock and associated low chemical-weathering
Authors
Karen C. Rice, Jason R. Price
Response to L. Land comment on Bricker, Rice, Bricker (2014) From Headwaters to Coast: Influence of human activities on water quality of the Potomac River Estuary. Aquatic Geochemistry 20: 291-324
Overabundance of nutrients is considered one of the top challenges to most populated coastal water bodies, including Chesapeake Bay (Executive Order 13508). As scientists, one of our responsibilities is to contribute to the discussion and evaluation of management actions that have the potential to decrease pollution with concomitant improvement of water quality. Results of our science should infor
Authors
Suzanne B. Bricker, Karen C. Rice, III Bricker
Synthesis and interpretation of surface-water quality and aquatic biota data collected in Shenandoah National Park, Virginia, 1979-2009
Shenandoah National Park in northern and central Virginia protects 777 square kilometers of mountain terrain in the Blue Ridge physiographic province and more than 90 streams containing diverse aquatic biota. Park managers and visitors are interested in the water quality of park streams and its ability to support healthy coldwater communities and species, such as the native brook trout (Salvelinus
Authors
John D. Jastram, Craig D. Snyder, Nathaniel P. Hitt, Karen C. Rice
Mass-balance modeling of mineral weathering rates and CO2 consumption in the forested, metabasaltic Hauver Branch watershed, Catoctin Mountain, Maryland, USA
Mineral weathering rates and a forest macronutrient uptake stoichiometry were determined for the forested, metabasaltic Hauver Branch watershed in north-central Maryland, USA. Previous studies of Hauver Branch have had an insufficient number of analytes to permit determination of rates of all the minerals involved in chemical weathering, including biomass. More equations in the mass-balance matrix
Authors
Karen C. Rice, Jason R. Price, David W. Szymanski
Spatial and temporal trends in runoff at long-term streamgages within and near the Chesapeake Bay Watershed
Long-term streamflow data within the Chesapeake Bay watershed and surrounding area were analyzed in an attempt to identify trends in streamflow. Data from 30 streamgages near and within the Chesapeake Bay watershed were selected from 1930 through 2010 for analysis. Streamflow data were converted to runoff and trend slopes in percent change per decade were calculated. Trend slopes for three runoff
Authors
Karen C. Rice, Robert M. Hirsch
Acidification of Earth: An assessment across mechanisms and scales
In this review article, anthropogenic activities that cause acidification of Earth’s air, waters, and soils are examined. Although there are many mechanisms of acidification, the focus is on the major ones, including emissions from combustion of fossil fuels and smelting of ores, mining of coal and metal ores, and application of nitrogen fertilizer to soils, by elucidating the underlying biogeoche
Authors
Karen C. Rice, Janet S. Herman
Evaluation of Bayesian estimation of a hidden continuous-time Markov chain model with application to threshold violation in water-quality indicators
Natural resource managers require information concerning the frequency, duration, and long-term probability of occurrence of water-quality indicator (WQI) violations of defined thresholds. The timing of these threshold crossings often is hidden from the observer, who is restricted to relatively infrequent observations. Here, a model for the hidden process is linked with a model for the observatio
Authors
Frank A. Deviney, Karen C. Rice, Donald E. Brown
Assessment of salinity intrusion in the James and Chickahominy Rivers as a result of simulated sea-level rise in Chesapeake Bay, East Coast, USA
Global sea level is rising, and the relative rate in the Chesapeake Bay region of the East Coast of the United States is greater than the worldwide rate. Sea-level rise can cause saline water to migrate upstream in estuaries and rivers, threatening freshwater habitat and drinking-water supplies. The effects of future sea-level rise on two tributaries of Chesapeake Bay, the James and Chickahominy (
Authors
Karen C. Rice, Bo Hong, Jian Shen
Simulated changes in salinity in the York and Chickahominy Rivers from projected sea-level rise in Chesapeake Bay
As a result of climate change and variability, sea level is rising throughout the world, but the rate along the east coast of the United States is higher than the global mean rate. The U.S. Geological Survey, in cooperation with the City of Newport News, Virginia, conducted a study to evaluate the effects of possible future sea-level rise on the salinity front in two tributaries to Chesapeake Bay,
Authors
Karen C. Rice, Mark Bennett, Jian Shen
The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005-2006
Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product aminomethylphosphonic aci
Authors
William A. Battaglin, Karen C. Rice, Michael J. Focazio, Sue Salmons, Robert X. Barry