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Theodore Melis, Ph.D.

Theodore "Teo" Melis serves as the Deputy Center Director of the Southwest Biological Science Center.

Science and Products

Filter Total Items: 44

Using large-scale flow experiments to rehabilitate Colorado River ecosystem function in Grand Canyon: Basis for an adaptive climate-resilient strategy

Adaptive management of Glen Canyon Dam is improving downstream resources of the Colorado River in Glen Canyon National Recreation Area and Grand Canyon National Park. The Glen Canyon Dam Adaptive Management Program (AMP), a federal advisory committee of 25 members with diverse special interests tasked to advise the U.S. Department of the Interior), was established in 1997 in response to the 1992 G
Authors
Theodore S. Melis, William E. Pine, Josh Korman, Michael D. Yard, Shaleen Jain, Roger S. Pulwarty
By
Ecosystems Mission Area, Southwest Biological Science Center

Bed texture mapping in large rivers using recreational-grade sidescan sonar

The size-distribution and spatial organization of bed sediment, or bed ‘texture’, is a fundamental attribute of natural channels and is one important component of the physical habitat of aquatic ecosystems. ‘Recreational-grade’ sidescan sonar systems now offer the possibility of imaging, and subsequently quantifying bed texture at high resolution with minimal cost, or logistical effort. We are inv
Authors
Daniel Hamill, Joseph M. Wheaton, Daniel D. Buscombe, Paul E. Grams, Theodore S. Melis
By
Ecosystems Mission Area, Southwest Biological Science Center

Surprise and opportunity for learning in Grand Canyon: the Glen Canyon Dam Adaptive Management Program

With a focus on resources of the Colorado River ecosystem below Glen Canyon Dam, the Glen Canyon Dam Adaptive Management Program has included a variety of experimental policy tests, ranging from manipulation of water releases from the dam to removal of non-native fish within Grand Canyon National Park. None of these field-scale experiments has yet produced unambiguous results in terms of managemen
Authors
Theodore S. Melis, Carl Walters, Josh Korman
By
Ecosystems Mission Area, Southwest Biological Science Center

Building sandbars in the Grand Canyon

In 1963, the U.S. Department of the Interior’s Bureau of Reclamation finished building Glen Canyon Dam on the Colorado River in northern Arizona, 25 kilometers upstream from Grand Canyon National Park. The dam impounded 300 kilometers of the Colorado River, creating Lake Powell, the nation’s second largest reservoir. By 1974, scientists found that the downstream river’s alluvial sandbars were erod
Authors
Paul E. Grams, John C. Schmidt, Scott A. Wright, David Topping, Theodore S. Melis, David M. Rubin
By
Ecosystems Mission Area, Southwest Biological Science Center

Large river bed sediment characterization with low-cost sidecan sonar: Case studies from two setting in the Colorado (Arizona) and Penobscot (Maine) Rivers

Mapping subaqueous riverbed sediment grain size across channels and in nearshore areas typically used by fish and benthic invertebrates is difficult where and when the water flow is too swift or deep to wade yet impractical to access with large boats and instruments. Fluvial characteristics can further constrain sampling options, particularly where flow depth, water column turbidity or channel bot
Authors
Daniel D. Buscombe, Paul E. Grams, Theodore S. Melis, Sean Smith
By
Ecosystems Mission Area, Southwest Biological Science Center

Design of a sediment-monitoring gaging network on ephemeral tributaries of the Colorado River in Glen, Marble, and Grand Canyons, Arizona

Management of sediment in rivers downstream from dams requires knowledge of both the sediment supply and downstream sediment transport. In some dam-regulated rivers, the amount of sediment supplied by easily measured major tributaries may overwhelm the amount of sediment supplied by the more difficult to measure lesser tributaries. In this first class of rivers, managers need only know the amount
Authors
Ronald E. Griffiths, David J. Topping, Robert S. Anderson, Gregory S. Hancock, Theodore S. Melis
By
Ecosystems Mission Area, Southwest Biological Science Center

Are large-scale flow experiments informing the science and management of freshwater ecosystems?

Greater scientific knowledge, changing societal values, and legislative mandates have emphasized the importance of implementing large-scale flow experiments (FEs) downstream of dams. We provide the first global assessment of FEs to evaluate their success in advancing science and informing management decisions. Systematic review of 113 FEs across 20 countries revealed that clear articulation of exp
Authors
Julian D. Olden, Christopher P. Konrad, Theodore S. Melis, Mark J. Kennard, Mary Freeman, Meryl C. Mims, Erin N. Bray, Keith B. Gido, Nina P. Hemphill, David A. Lytle, Laura E. McMullen, Mark Pyron, Christopher T. Robinson, John C. Schmidt, John G. Williams
By
Ecosystems Mission Area, Water Resources Mission Area, Washington Water Science Center, Forest and Rangeland Ecosystem Science Center

U.S. Geological Survey suspended-sediment surrogate research, Part II: Optic technologies

No abstract available.
Authors
John R. Gray, Daniel J. Gooding, Theodore S. Melis, David J. Topping, Patrick P. Rasmussen
By
Water Resources Mission Area

U.S. Geological Survey research on surrogate measurements for suspended sediment

The U.S. Geological Survey is evaluating potentially useful surrogate instruments and methods for inferring the physical characteristics of suspended sediments. Instruments operating on bulk acoustic, bulk and digital optic, laser, and pressure-differential technologies are being tested in riverine and laboratory settings for their usefulness to Federal agencies toward providing quantifiably relia
Authors
John R. Gray, Theodore S. Melis, Eduardo Patiño, Matthew C. Larsen, David J. Topping, Patrick P. Rasmussen, Carlos Figueroa-Alamo
By
Water Resources Mission Area

Evaluation of sediment-surrogate technologies for computation of suspended-sediment transport

No abstract available.
Authors
John R. Gray, Eduardo Patiño, Patrick P. Rasmussen, Matthew C. Larsen, Theodore S. Melis, David J. Topping, Michael S. Runner, Carlos Figueroa Alamo
By
Water Resources Mission Area

Design and maintenance of a network for collecting high-resolution suspended-sediment data at remote locations on rivers, with examples from the Colorado River

Management of sand and finer sediment in fluvial settings has become increasingly important for reasons ranging from endangered-species habitat to transport of sediment-associated contaminants. In all rivers, some fraction of the suspended load is transported as washload, and some as suspended bed material. Typically, the washload is composed of silt-and-clay-size sediment, and the suspended bed m
Authors
Ronald E. Griffiths, David J. Topping, Timothy Andrews, Glenn E. Bennett, Thomas A. Sabol, Theodore S. Melis
By
Water Resources Mission Area, Ecosystems Mission Area, Southwest Biological Science Center

An approach for modeling sediment budgets in supply-limited rivers

Reliable predictions of sediment transport and river morphology in response to variations in natural and human-induced drivers are necessary for river engineering and management. Because engineering and management applications may span a wide range of space and time scales, a broad spectrum of modeling approaches has been developed, ranging from suspended-sediment "rating curves" to complex three-
Authors
Scott A. Wright, David J. Topping, David M. Rubin, Theodore S. Melis
By
Water Resources Mission Area, California Water Science Center, Pacific Coastal and Marine Science Center, Pacific Islands Water Science Center, Southwest Biological Science Center
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Looking at Glen Canyon Dam from the Colorado River

Amazon Dams Network: Advancing Integrative Research and Adaptive Management of Social-Ecological Systems Transformed by Hydroelectric Dams

The overall goal of this project is to advance inter- and trans-disciplinary research coordination, focusing on the transformation of social-ecological systems by hydroelectric dam construction in the Amazon and the United States. The experience gained by Southwest Biological Science Center researchers working on the Glen Canyon Dam Adaptive Management Program in the Colorado River in Grand Canyon...
By
Ecosystems Mission Area, Species Management Research Program, Southwest Biological Science Center
link

Amazon Dams Network: Advancing Integrative Research and Adaptive Management of Social-Ecological Systems Transformed by Hydroelectric Dams

The overall goal of this project is to advance inter- and trans-disciplinary research coordination, focusing on the transformation of social-ecological systems by hydroelectric dam construction in the Amazon and the United States. The experience gained by Southwest Biological Science Center researchers working on the Glen Canyon Dam Adaptive Management Program in the Colorado River in Grand Canyon...
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USGS Scientists Discuss Climate, Drought and Resource Management at Colorado Plateau Conference

US Geological Survey scientists are presenting on numerous topics related to climate change, drought and resource management at the 13th Biennial...

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