Allen C Gellis, Ph.D. (Former Employee)
Science and Products
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Characteristic length scales and time-averaged transport velocities of suspended sediment in the mid-Atlantic Region, USA Characteristic length scales and time-averaged transport velocities of suspended sediment in the mid-Atlantic Region, USA
Watershed Best Management Practices (BMPs) are often designed to reduce loading from particle-borne contaminants, but the temporal lag between BMP implementation and improvement in receiving water quality is difficult to assess because particles are only moved downstream episodically, resting for long periods in storage between transport events. A theory is developed that describes the...
Authors
James Pizzuto, Edward Schenk, Cliff Hupp, Allen Gellis, Greg Noe, Elyse Williamson, Diana Karwan, Michael O'Neal, Julia Marquard, Rolf Aalto, Denis Newbold
Sediment source analysis in the Linganore Creek watershed, Maryland, USA, using the sediment fingerprinting approach: 2008 to 2010 Sediment source analysis in the Linganore Creek watershed, Maryland, USA, using the sediment fingerprinting approach: 2008 to 2010
Purpose: Fine-grained sediment is an important pollutant in streams and estuaries, including the Chesapeake Bay in the USA. The objective of this study was to determine the sources of fine-grained sediment using the sediment fingerprinting approach in the Linganore Creek watershed, a tributary to the Chesapeake Bay. Materials and methods: The sediment fingerprinting approach was used in...
Authors
Allen C. Gellis, Gregory B. Noe
Factors influencing storm-generated suspended-sediment concentrations and loads in four basins of contrasting land use, humid-tropical Puerto Rico Factors influencing storm-generated suspended-sediment concentrations and loads in four basins of contrasting land use, humid-tropical Puerto Rico
The significant characteristics controlling the variability in storm-generated suspended-sediment loads and concentrations were analyzed for four basins of differing land use (forest, pasture, cropland, and urbanizing) in humid-tropical Puerto Rico. Statistical analysis involved stepwise regression on factor scores. The explanatory variables were attributes of flow, hydrograph peaks, and...
Authors
Allen C. Gellis
Developing a new stream metric for comparing stream function using a bank-floodplain sediment budget: a case study of three Piedmont streams Developing a new stream metric for comparing stream function using a bank-floodplain sediment budget: a case study of three Piedmont streams
A bank and floodplain sediment budget was created for three Piedmont streams tributary to the Chesapeake Bay. The watersheds of each stream varied in land use from urban (Difficult Run) to urbanizing (Little Conestoga Creek) to agricultural (Linganore Creek). The purpose of the study was to determine the relation between geomorphic parameters and sediment dynamics and to develop a...
Authors
Edward Schenk, Cliff Hupp, Allen Gellis, Greg Noe
Erosion, storage, and transport of sediment in two subbasins of the Rio Puerco, New Mexico Erosion, storage, and transport of sediment in two subbasins of the Rio Puerco, New Mexico
Arroyos in the American Southwest proceed through cut-and-fill cycles that operate at centennial to millennial time scales. The geomorphic community has put much effort into understanding the causes of arroyo cutting in the late Quaternary and in the modern record (late 1800s), while little effort has gone into understanding how arroyos fill and the sources of this fill. Here, we...
Authors
A. C. Gellis, M.J. Pavich, A.L. Ellwein, S. Aby, I. Clark, M.E. Wieczorek, R. Viger
Sediment dynamics in the restored reach of the Kissimmee River Basin, Florida: A vast subtropical riparian wetland Sediment dynamics in the restored reach of the Kissimmee River Basin, Florida: A vast subtropical riparian wetland
Historically, the Kissimmee River Basin consisted of a broad nearly annually inundated riparian wetland similar in character to tropical Southern Hemisphere large rivers. The river was channelized in the 1960s and 1970s, draining the wetland. The river is currently being restored with over 10 000 hectares of wetlands being reconnected to 70 river km of naturalized channel. We monitored...
Authors
E.R. Schenk, C.R. Hupp, A. Gellis
Total nitrogen and suspended-sediment loads and identification of suspended-sediment sources in the Laurel Hill Creek watershed, Somerset County, Pennsylvania, water years 2010-11 Total nitrogen and suspended-sediment loads and identification of suspended-sediment sources in the Laurel Hill Creek watershed, Somerset County, Pennsylvania, water years 2010-11
Laurel Hill Creek is a watershed of 125 square miles located mostly in Somerset County, Pennsylvania, with small areas extending into Fayette and Westmoreland Counties. The upper part of the watershed is on the Pennsylvania Department of Environmental Protection 303(d) list of impaired streams because of siltation, nutrients, and low dissolved oxygen concentrations. The objectives of...
Authors
Ronald Sloto, Allen C. Gellis, Daniel Galeone
Anthropocene streams and base-level controls from historic dams in the unglaciated mid-Atlantic region, USA Anthropocene streams and base-level controls from historic dams in the unglaciated mid-Atlantic region, USA
Recently, widespread valley-bottom damming for water power was identified as a primary control on valley sedimentation in the mid-Atlantic US during the late seventeenth to early twentieth century. The timing of damming coincided with that of accelerated upland erosion during post-European settlement land-use change. In this paper, we examine the impact of local drops in base level on...
Authors
Dorothy Merritts, Robert Walter, Michael Rahnis, Jeff Hartranft, Scott Cox, Allen Gellis, Noel Potter, William Hilgartner, Michael Langland, Lauren Manion, Caitlin Lippincott, Sauleh Siddiqui, Zain Rehman, Chris Scheid, Laura Kratz, Andrea Shilling, Matthew Jenschke, Katherine Datin, Elizabeth Cranmer, Austin Reed, Derek Matuszewski, Mark Voli, Erik Ohlson, Ali Neugebauer, Aakash Ahamed, Conor Neal, Allison Winter, Steven Becker
Hydrologic Data for Deep Creek Lake and Selected Tributaries, Garrett County, Maryland, 2007-08 Hydrologic Data for Deep Creek Lake and Selected Tributaries, Garrett County, Maryland, 2007-08
Introduction Recent and ongoing efforts to develop the land in the area around Deep Creek Lake, Garrett County, Maryland, are expected to change the volume of sediment moving toward and into the lake, as well as impact the water quality of the lake and its many tributaries. With increased development, there is an associated increased demand for groundwater and surface-water withdrawals...
Authors
William Banks, William Davies, Allen C. Gellis, Andrew LaMotte, Wendy McPherson, Daniel Soeder
Suspended-sediment sources in an urban watershed, Northeast Branch Anacostia River, Maryland Suspended-sediment sources in an urban watershed, Northeast Branch Anacostia River, Maryland
Fine sediment sources were characterized by chemical composition in an urban watershed, the Northeast Branch Anacostia River, which drains to the Chesapeake Bay. Concentrations of 63 elements and two radionuclides were measured in possible land-based sediment sources and suspended sediment collected from the water column at the watershed outlet during storm events. These tracer...
Authors
Olivia Devereux, Karen Prestegaard, Brian Needelman, Allen C. Gellis
Fluvial sediment in the environment: a national challenge Fluvial sediment in the environment: a national challenge
Sediment and sediment-associated constituents can contribute substantially to water-quality impairment. In the past, sediment was viewed mainly as an engineering problem that affected reservoir storage capacity, shipping channel maintenance, and bridge scour, as well as the loss of agricultural soil. Sediment is now recognized as a major cause of aquatic system degradation in many rivers...
Authors
Matthew Larsen, Allen C. Gellis, G. Glysson, John Gray, Arthur Horowitz
Sources, transport, and storage of sediment at selected sites in the Chesapeake Bay Watershed Sources, transport, and storage of sediment at selected sites in the Chesapeake Bay Watershed
The Chesapeake Bay Watershed covers 165,800 square kilometers and is supplied with water and sediment from five major physiographic provinces: Appalachian Plateau, Blue Ridge, Coastal Plain, Piedmont, and the Valley and Ridge. Suspended-sediment loads measured in the Chesapeake Bay Watershed showed that the Piedmont Physiographic Province has the highest rates of modern (20th Century)...
Authors
Allen C. Gellis, Cliff Hupp, Milan Pavich, Jurate Landwehr, William Banks, Bernard Hubbard, Michael Langland, Jerry Ritchie, Joanna Reuter
Science and Products
Filter Total Items: 16
No Result Found
Filter Total Items: 66
Characteristic length scales and time-averaged transport velocities of suspended sediment in the mid-Atlantic Region, USA Characteristic length scales and time-averaged transport velocities of suspended sediment in the mid-Atlantic Region, USA
Watershed Best Management Practices (BMPs) are often designed to reduce loading from particle-borne contaminants, but the temporal lag between BMP implementation and improvement in receiving water quality is difficult to assess because particles are only moved downstream episodically, resting for long periods in storage between transport events. A theory is developed that describes the...
Authors
James Pizzuto, Edward Schenk, Cliff Hupp, Allen Gellis, Greg Noe, Elyse Williamson, Diana Karwan, Michael O'Neal, Julia Marquard, Rolf Aalto, Denis Newbold
Sediment source analysis in the Linganore Creek watershed, Maryland, USA, using the sediment fingerprinting approach: 2008 to 2010 Sediment source analysis in the Linganore Creek watershed, Maryland, USA, using the sediment fingerprinting approach: 2008 to 2010
Purpose: Fine-grained sediment is an important pollutant in streams and estuaries, including the Chesapeake Bay in the USA. The objective of this study was to determine the sources of fine-grained sediment using the sediment fingerprinting approach in the Linganore Creek watershed, a tributary to the Chesapeake Bay. Materials and methods: The sediment fingerprinting approach was used in...
Authors
Allen C. Gellis, Gregory B. Noe
Factors influencing storm-generated suspended-sediment concentrations and loads in four basins of contrasting land use, humid-tropical Puerto Rico Factors influencing storm-generated suspended-sediment concentrations and loads in four basins of contrasting land use, humid-tropical Puerto Rico
The significant characteristics controlling the variability in storm-generated suspended-sediment loads and concentrations were analyzed for four basins of differing land use (forest, pasture, cropland, and urbanizing) in humid-tropical Puerto Rico. Statistical analysis involved stepwise regression on factor scores. The explanatory variables were attributes of flow, hydrograph peaks, and...
Authors
Allen C. Gellis
Developing a new stream metric for comparing stream function using a bank-floodplain sediment budget: a case study of three Piedmont streams Developing a new stream metric for comparing stream function using a bank-floodplain sediment budget: a case study of three Piedmont streams
A bank and floodplain sediment budget was created for three Piedmont streams tributary to the Chesapeake Bay. The watersheds of each stream varied in land use from urban (Difficult Run) to urbanizing (Little Conestoga Creek) to agricultural (Linganore Creek). The purpose of the study was to determine the relation between geomorphic parameters and sediment dynamics and to develop a...
Authors
Edward Schenk, Cliff Hupp, Allen Gellis, Greg Noe
Erosion, storage, and transport of sediment in two subbasins of the Rio Puerco, New Mexico Erosion, storage, and transport of sediment in two subbasins of the Rio Puerco, New Mexico
Arroyos in the American Southwest proceed through cut-and-fill cycles that operate at centennial to millennial time scales. The geomorphic community has put much effort into understanding the causes of arroyo cutting in the late Quaternary and in the modern record (late 1800s), while little effort has gone into understanding how arroyos fill and the sources of this fill. Here, we...
Authors
A. C. Gellis, M.J. Pavich, A.L. Ellwein, S. Aby, I. Clark, M.E. Wieczorek, R. Viger
Sediment dynamics in the restored reach of the Kissimmee River Basin, Florida: A vast subtropical riparian wetland Sediment dynamics in the restored reach of the Kissimmee River Basin, Florida: A vast subtropical riparian wetland
Historically, the Kissimmee River Basin consisted of a broad nearly annually inundated riparian wetland similar in character to tropical Southern Hemisphere large rivers. The river was channelized in the 1960s and 1970s, draining the wetland. The river is currently being restored with over 10 000 hectares of wetlands being reconnected to 70 river km of naturalized channel. We monitored...
Authors
E.R. Schenk, C.R. Hupp, A. Gellis
Total nitrogen and suspended-sediment loads and identification of suspended-sediment sources in the Laurel Hill Creek watershed, Somerset County, Pennsylvania, water years 2010-11 Total nitrogen and suspended-sediment loads and identification of suspended-sediment sources in the Laurel Hill Creek watershed, Somerset County, Pennsylvania, water years 2010-11
Laurel Hill Creek is a watershed of 125 square miles located mostly in Somerset County, Pennsylvania, with small areas extending into Fayette and Westmoreland Counties. The upper part of the watershed is on the Pennsylvania Department of Environmental Protection 303(d) list of impaired streams because of siltation, nutrients, and low dissolved oxygen concentrations. The objectives of...
Authors
Ronald Sloto, Allen C. Gellis, Daniel Galeone
Anthropocene streams and base-level controls from historic dams in the unglaciated mid-Atlantic region, USA Anthropocene streams and base-level controls from historic dams in the unglaciated mid-Atlantic region, USA
Recently, widespread valley-bottom damming for water power was identified as a primary control on valley sedimentation in the mid-Atlantic US during the late seventeenth to early twentieth century. The timing of damming coincided with that of accelerated upland erosion during post-European settlement land-use change. In this paper, we examine the impact of local drops in base level on...
Authors
Dorothy Merritts, Robert Walter, Michael Rahnis, Jeff Hartranft, Scott Cox, Allen Gellis, Noel Potter, William Hilgartner, Michael Langland, Lauren Manion, Caitlin Lippincott, Sauleh Siddiqui, Zain Rehman, Chris Scheid, Laura Kratz, Andrea Shilling, Matthew Jenschke, Katherine Datin, Elizabeth Cranmer, Austin Reed, Derek Matuszewski, Mark Voli, Erik Ohlson, Ali Neugebauer, Aakash Ahamed, Conor Neal, Allison Winter, Steven Becker
Hydrologic Data for Deep Creek Lake and Selected Tributaries, Garrett County, Maryland, 2007-08 Hydrologic Data for Deep Creek Lake and Selected Tributaries, Garrett County, Maryland, 2007-08
Introduction Recent and ongoing efforts to develop the land in the area around Deep Creek Lake, Garrett County, Maryland, are expected to change the volume of sediment moving toward and into the lake, as well as impact the water quality of the lake and its many tributaries. With increased development, there is an associated increased demand for groundwater and surface-water withdrawals...
Authors
William Banks, William Davies, Allen C. Gellis, Andrew LaMotte, Wendy McPherson, Daniel Soeder
Suspended-sediment sources in an urban watershed, Northeast Branch Anacostia River, Maryland Suspended-sediment sources in an urban watershed, Northeast Branch Anacostia River, Maryland
Fine sediment sources were characterized by chemical composition in an urban watershed, the Northeast Branch Anacostia River, which drains to the Chesapeake Bay. Concentrations of 63 elements and two radionuclides were measured in possible land-based sediment sources and suspended sediment collected from the water column at the watershed outlet during storm events. These tracer...
Authors
Olivia Devereux, Karen Prestegaard, Brian Needelman, Allen C. Gellis
Fluvial sediment in the environment: a national challenge Fluvial sediment in the environment: a national challenge
Sediment and sediment-associated constituents can contribute substantially to water-quality impairment. In the past, sediment was viewed mainly as an engineering problem that affected reservoir storage capacity, shipping channel maintenance, and bridge scour, as well as the loss of agricultural soil. Sediment is now recognized as a major cause of aquatic system degradation in many rivers...
Authors
Matthew Larsen, Allen C. Gellis, G. Glysson, John Gray, Arthur Horowitz
Sources, transport, and storage of sediment at selected sites in the Chesapeake Bay Watershed Sources, transport, and storage of sediment at selected sites in the Chesapeake Bay Watershed
The Chesapeake Bay Watershed covers 165,800 square kilometers and is supplied with water and sediment from five major physiographic provinces: Appalachian Plateau, Blue Ridge, Coastal Plain, Piedmont, and the Valley and Ridge. Suspended-sediment loads measured in the Chesapeake Bay Watershed showed that the Piedmont Physiographic Province has the highest rates of modern (20th Century)...
Authors
Allen C. Gellis, Cliff Hupp, Milan Pavich, Jurate Landwehr, William Banks, Bernard Hubbard, Michael Langland, Jerry Ritchie, Joanna Reuter