Allen C Gellis, Ph.D. (Former Employee)
Science and Products
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Streamflow and fluvial sediment transport in Pool C, restored section of the Kissimmee River Streamflow and fluvial sediment transport in Pool C, restored section of the Kissimmee River
The Kissimmee River Restoration Project was authorized by Congress in 1992 to restore more than 64 km2 (square kilometers) of river/floodplain ecosystem including 69 km of meandering river channel and 10,900 hectares (ha) of wetlands. Although biologic monitoring is an integral and active part of the Kissimmee River restoration, by 2007 geomorphic monitoring that included sediment...
Authors
J. Leroy Pearman, Allen C. Gellis, Philip J. Habermehl
Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management
The purpose of this report is to present a synthesis of the USGS Chesapeake Bay science related to the 2001-06 goals and provide implications for environmental management. The report provides USGS findings that address the science needs of the Chesapeake Bay Program (CBP) restoration goals and includes summaries of 1. land-use change; 2. water quality in the watershed, including...
Authors
Scott W. Ator, Vicki S. Blazer, John W. Brakebill, Donald R. Cahoon, Peter R. Claggett, Thomas M. Cronin, Judith M. Denver, Christine L. Densmore, Allen C. Gellis, Cliff R. Hupp, Jurate M. Landwehr, Michael J. Langland, Christopher A. Ottinger, Milan J. Pavich, Matthew C. Perry, Scott W. Phillips, Stephen D. Preston, Jeff P. Raffensperger, Barnett A. Rattner, Nancy B. Rybicki, Debra A. Willard
Land-use effects on erosion, sediment yields, and reservoir sedimentation: A case study in the Lago Loiza Basin, Puerto Rico Land-use effects on erosion, sediment yields, and reservoir sedimentation: A case study in the Lago Loiza Basin, Puerto Rico
Lago Loíza impounded in 1953 to supply San Juan, Puerto Rico, with drinking water; by 1994, it had lost 47% of its capacity. To characterize sedimentation in Lago Loíza, a study combining land-use history, hillslope erosion rates, and subbasin sediment yields was conducted. Sedimentation rates during the early part of the reservoir’s operation (1953– 1963) were slightly higher than the...
Authors
Allen C. Gellis, Richard M. T. Webb, S. C. McIntyre, William J. Wolfe
Channel and hillslope processes revisited in the Arroyo de los Frijoles watershed near Santa Fe, New Mexico Channel and hillslope processes revisited in the Arroyo de los Frijoles watershed near Santa Fe, New Mexico
Detailed documentation of geomorphic changes in the landscape of more than a few years is rarely possible. Channel cross sections, channel profiles, sediment deposition behind dams, and hillslope-erosion plots, originally benchmarked within several watersheds outside Santa Fe, New Mexico, in the 1950’s and 1960’s, for a 1966 report that documented processes and rates of arid-region...
Authors
Allen C. Gellis, William W. Emmett, Luna Bergere Leopold
Using cosmogenic nuclides to contrast rates of erosion and sediment yield in a semi-arid, arroyo-dominated landscape, Rio Puerco Basin, New Mexico Using cosmogenic nuclides to contrast rates of erosion and sediment yield in a semi-arid, arroyo-dominated landscape, Rio Puerco Basin, New Mexico
Analysis of in-situ-produced 10Be and 26Al in 52 fluvial sediment samples shows that millennial-scale rates of erosion vary widely (7 to 366 m Ma-1) through the lithologically and topographically complex Rio Puerco Basin of northern New Mexico. Using isotopic analysis of both headwater and downstream samples, we determined that the semi-arid, Rio Puerco Basin is eroding, on average...
Authors
P.R. Bierman, J.M. Reuter, M. Pavich, A. C. Gellis, M.W. Caffee, J. Larsen
Summary of suspended-sediment data for streams draining the Chesapeake Bay Watershed, water years 1952-2002 Summary of suspended-sediment data for streams draining the Chesapeake Bay Watershed, water years 1952-2002
U.S. Geological Survey suspended-sediment data from 1952 to 2002 from selected stream-gaging stations draining the nontidal parts of the Chesapeake Bay Watershed were summarized to identify areas in the Watershed with high suspended-sediment loads, yields, and concentrations. The suspended-sediment load data were separated into two periods, 1952?1984 and 1985?2001. In 1985, the...
Authors
Allen C. Gellis, William S.L. Banks, Michael J. Langland, Sarah K. Martucci
Science and Products
Filter Total Items: 16
No Result Found
Filter Total Items: 66
Streamflow and fluvial sediment transport in Pool C, restored section of the Kissimmee River Streamflow and fluvial sediment transport in Pool C, restored section of the Kissimmee River
The Kissimmee River Restoration Project was authorized by Congress in 1992 to restore more than 64 km2 (square kilometers) of river/floodplain ecosystem including 69 km of meandering river channel and 10,900 hectares (ha) of wetlands. Although biologic monitoring is an integral and active part of the Kissimmee River restoration, by 2007 geomorphic monitoring that included sediment...
Authors
J. Leroy Pearman, Allen C. Gellis, Philip J. Habermehl
Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management
The purpose of this report is to present a synthesis of the USGS Chesapeake Bay science related to the 2001-06 goals and provide implications for environmental management. The report provides USGS findings that address the science needs of the Chesapeake Bay Program (CBP) restoration goals and includes summaries of 1. land-use change; 2. water quality in the watershed, including...
Authors
Scott W. Ator, Vicki S. Blazer, John W. Brakebill, Donald R. Cahoon, Peter R. Claggett, Thomas M. Cronin, Judith M. Denver, Christine L. Densmore, Allen C. Gellis, Cliff R. Hupp, Jurate M. Landwehr, Michael J. Langland, Christopher A. Ottinger, Milan J. Pavich, Matthew C. Perry, Scott W. Phillips, Stephen D. Preston, Jeff P. Raffensperger, Barnett A. Rattner, Nancy B. Rybicki, Debra A. Willard
Land-use effects on erosion, sediment yields, and reservoir sedimentation: A case study in the Lago Loiza Basin, Puerto Rico Land-use effects on erosion, sediment yields, and reservoir sedimentation: A case study in the Lago Loiza Basin, Puerto Rico
Lago Loíza impounded in 1953 to supply San Juan, Puerto Rico, with drinking water; by 1994, it had lost 47% of its capacity. To characterize sedimentation in Lago Loíza, a study combining land-use history, hillslope erosion rates, and subbasin sediment yields was conducted. Sedimentation rates during the early part of the reservoir’s operation (1953– 1963) were slightly higher than the...
Authors
Allen C. Gellis, Richard M. T. Webb, S. C. McIntyre, William J. Wolfe
Channel and hillslope processes revisited in the Arroyo de los Frijoles watershed near Santa Fe, New Mexico Channel and hillslope processes revisited in the Arroyo de los Frijoles watershed near Santa Fe, New Mexico
Detailed documentation of geomorphic changes in the landscape of more than a few years is rarely possible. Channel cross sections, channel profiles, sediment deposition behind dams, and hillslope-erosion plots, originally benchmarked within several watersheds outside Santa Fe, New Mexico, in the 1950’s and 1960’s, for a 1966 report that documented processes and rates of arid-region...
Authors
Allen C. Gellis, William W. Emmett, Luna Bergere Leopold
Using cosmogenic nuclides to contrast rates of erosion and sediment yield in a semi-arid, arroyo-dominated landscape, Rio Puerco Basin, New Mexico Using cosmogenic nuclides to contrast rates of erosion and sediment yield in a semi-arid, arroyo-dominated landscape, Rio Puerco Basin, New Mexico
Analysis of in-situ-produced 10Be and 26Al in 52 fluvial sediment samples shows that millennial-scale rates of erosion vary widely (7 to 366 m Ma-1) through the lithologically and topographically complex Rio Puerco Basin of northern New Mexico. Using isotopic analysis of both headwater and downstream samples, we determined that the semi-arid, Rio Puerco Basin is eroding, on average...
Authors
P.R. Bierman, J.M. Reuter, M. Pavich, A. C. Gellis, M.W. Caffee, J. Larsen
Summary of suspended-sediment data for streams draining the Chesapeake Bay Watershed, water years 1952-2002 Summary of suspended-sediment data for streams draining the Chesapeake Bay Watershed, water years 1952-2002
U.S. Geological Survey suspended-sediment data from 1952 to 2002 from selected stream-gaging stations draining the nontidal parts of the Chesapeake Bay Watershed were summarized to identify areas in the Watershed with high suspended-sediment loads, yields, and concentrations. The suspended-sediment load data were separated into two periods, 1952?1984 and 1985?2001. In 1985, the...
Authors
Allen C. Gellis, William S.L. Banks, Michael J. Langland, Sarah K. Martucci