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Year Published: 2017

Colorado River fish monitoring in Grand Canyon, Arizona; 2002–14 humpback chub aggregations

The humpback chub (Gila cypha) is an endangered cyprinid species endemic to the Colorado River. The largest remaining population of the species spawns and rears in the Little Colorado River in Grand Canyon. Construction and operation of Glen Canyon Dam has altered the main-stem Colorado River in Glen and Grand Canyons. Cold, clear water releases...

Persons, William R.; Van Haverbeke, David R.; Dodrill, Michael J.
Persons, W.R., Van Haverbeke, D.R., and Dodrill, M.J., 2017, Colorado River fish monitoring in Grand Canyon, Arizona; 2002–14 humpback chub aggregations: U.S. Geological Survey Open-File Report 2016–1177, 43 p., https://doi.org/10.3133/ofr20161177.

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Year Published: 2017

NDVI, scale invariance and the modifiable areal unit problem: An assessment of vegetation in the Adelaide Parklands

This research addresses the question as to whether or not the Normalised Difference Vegetation Index (NDVI) is scale invariant (i.e. constant over spatial aggregation) for pure pixels of urban vegetation. It has been long recognized that there are issues related to the modifiable areal unit problem (MAUP) pertaining to indices such as NDVI and...

Nouri, Hamideh; Anderson, Sharolyn; Sutton, Paul; Beecham, Simon; Nagler, Pamela L.; Jarchow, Christopher J.; Roberts, Dar A.
Nouri, Hamideh, Sharolyn Anderson, Paul Sutton, Simon Beecham, Pamela Nagler, Christopher J. Jarchow, Dar A. Roberts. 2017. NDVI, scale invariance and the modifiable areal unit problem: An assessment of vegetation in the Adelaide Parklands. Science of The Total Environment. Volumes 584–585, 15 April 2017, Pages 11–18 dx.doi.org/10.1016/j.scitotenv.2017.01.130 http://www.sciencedirect.com/science/article/pii/S0048969717301407

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Year Published: 2017

A detached eddy simulation model for the study of lateral separation zones along a large canyon-bound river

Lateral flow separation occurs in rivers where banks exhibit strong curvature. In canyon-boundrivers, lateral recirculation zones are the principal storage of fine-sediment deposits. A parallelized,three-dimensional, turbulence-resolving model was developed to study the flow structures along lateralseparation zones located in two pools along the...

Alvarez, Laura V.; Schmeeckle, Mark W.; Grams, Paul E.
Alvarez, L.A., Schmeeckle, M.W., and Grams, P.E., 2017, A detached eddy simulation model for the study of lateralseparation zones along a large canyon-bound river: Journal of Geophysical Research: Earth Surface, online, p. 1-25, 10.1002/2016JF003895

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Year Published: 2017

Scientific monitoring plan in support of the selected alternative of the Glen Canyon Dam Long-Term Experimental and Management Plan

IntroductionThe purpose of this document is to describe a strategy by which monitoring and research data in the natural and social sciences will be collected, analyzed, and provided to the U.S. Department of the Interior (DOI), its bureaus, and to the Glen Canyon Dam Adaptive Management Program (GCDAMP) in support of implementation of the Glen...

Vanderkooi, Scott P.; Kennedy, Theodore A.; Topping, David J.; Grams, Paul E.; Ward, David L.; Fairley, Helen C.; Bair, Lucas S.; Sankey, Joel B.; Yackulic, Charles B.; Schmidt, John C.
VanderKooi, S.P., Kennedy, T.A., Topping, D.J., Grams, P.E., Ward, D.L., Fairley, H.C., Bair, L.S., Sankey, J.B., Yackulic, C.B., and Schmidt, J.C., 2017, Scientific monitoring plan in support of the selected alternative of the Glen Canyon Dam Long-Term Experimental and Management Plan: U.S. Geological Survey Open-File Report 2017-1006, 18 p., https://doi.org/10.3133/ofr20171006.

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Year Published: 2017

Estimating the settling velocity of bioclastic sediment using common grain-size analysis techniques

Most techniques for estimating settling velocities of natural particles have been developed for siliciclastic sediments. Therefore, to understand how these techniques apply to bioclastic environments, measured settling velocities of bioclastic sedimentary deposits sampled from a nearshore fringing reef in Western Australia were compared with...

Cuttler, Michael V. W.; Lowe, Ryan J.; Falter, James L.; Buscombe, Daniel D.
Cuttler, M. V., Lowe, R.J., Falter, J.L., and Buscombe, D., 2016, Estimating the settling velocity of bioclastic sediment using common grain-size analysis techniques: Sedimentology, online, http://onlinelibrary.wiley.com/doi/10.1111/sed.12338/abstract?campaign=wolacceptedarticle

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Year Published: 2017

Shallow water benthic imaging and substrate characterization using recreational-grade sidescan-sonar

In recent years, lightweight, inexpensive, vessel-mounted ‘recreational grade’ sonar systems have rapidly grown in popularity among aquatic scientists, for swath imaging of benthic substrates. To promote an ongoing ‘democratization’ of acoustical imaging of shallow water environments, methods to carry out geometric and radiometric correction and...

Buscombe, Daniel D.
Buscombe, D., 2016, Shallow water benthic imaging and substrate characterization using recreational-grade sidescan-sonar: Environmental Modeling & Software, no. 89, p. 1-18, DOI: 10.1016/j.envsoft.2016.12.003

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Year Published: 2017

A report on genetic affinities and relatedness of Agassiz’s desert tortoises (Gopherus agassizii) at opposite ends of the Coachella Valley in California

This report summarizes the results for mtDNA and STR genotyping of 41 desert tortoise (Gopherus agassizii) DNA samples from opposite sides of the Coachella Valley: one sample from the west side at the Mesa wind energy facility in the Whitewater Hills and the other from the mouth of Cottonwood Canyon in Joshua Tree National Park, both within the...

Lovich, Jeffrey E.; Edwards, Taylor; Kreiser, Brian; Puffer, Shellie R.; Agha, Mickey
Lovich, J.E., Edwards, T., Kreiser, B., Puffer, M.R., and Agha, M., 2017, A report on genetic affinities and relatedness of Agassiz's desert tortoises (Gopherus agassizii) at opposite ends of the Coachella Valley in California, in Coachella Valley Multiple Species Habitat Conservation Plan/Natural Community Conservation Plan—2017 Annual Report: Palm Desert, Calif., Coachella Valley Conservation Commission, p. 131-146, http://www.cvmshcp.org/Annual%20Reports/Annual%20Report%202017.pdf.

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Year Published: 2017

Climate change and collapsing thermal niches of Mexican endemic reptiles

Recent climate change should result in expansion of species to northern or high elevation range margins, and contraction at southern and low elevation margins due to extinction. Climate models predict dramatic extinctions and distributional shifts in the next century, but there are few ground-truths of these dire forecasts leading to uncertainty...

Sinervo, Barry; Miles, Donald B.; Lara Reséndiz, Rafael A.; Lovich, Jeffrey E.; Ennen, Joshua R.; Müller, Johannes; Cooper, Robert D.; Rosen, Philip C.; Stewart, Joseph A. E.; Santos, Juan Carlos; Sites, Jack W.; Gibbons, Paul; Goode, Eric; Hillard, L. Scott; Welton, Luke; Agha, Mickey; Caetano, Gabriel; Vaughn, Mercy; Meléndez Torres, Cristina; Gadsden, Héctor; Casteñada Gaytán, Gamaliel; Galina-Tessaro, Patricia; Valle Jiménez, Fernando I.; Valdez-Villavicencio, Jorge H.; Martínez Méndez, Norberto; Woolrich Piña, Guillermo; Luja Molina, Victor; Díaz de la Vega Pérez, Aníbal; Arenas Moreno, Diego M.; Domínguez Guerrero, Saúl; Fierro, Natalia; Butterfield, Scott; Westpha, Michael; Huey, Raymond B.; Mautz, William; Sánchez-Cordero, Víctor; Méndez de la Cruz, Fausto R.

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Year Published: 2017

Diet patterns of island foxes on San Nicolas Island relative to feral cat removal

Island foxes (Urocyon littoralis) are a species of conservation concern that occur on six of the Channel Islands off the coast of southern California. We analysed island fox diet on San Nicolas Island during 2006–12 to assess the influence of the removal of feral cats (Felis catus) on the food use by foxes. Our objective was to determine whether...

Cypher, Brian L.; Kelly, Erica C.; Ferrara, Francesca J.; Drost, Charles A.; Westall, Tory L.; Hudgens, Brian

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Year Published: 2017

Disentangling the complexities of how legumes and their symbionts regulate plant nitrogen access and storage

Nitrogen (N) availability strongly influences the structure and function of ecosystems (e.g. Vitousek & Howarth, 1991), but only a relatively small number of microbial groups have the ability to convert the N2 in our atmosphere into biologically available forms.This process, N2 fixation, is the dominant source of new N to the biosphere...

Reed, Sasha C.
Reed, S., 2017, Disentangling the complexities of how legumes and their symbionts regulate plant nitrogen access and storage—Commentary: New Phytologist, v. 213, no. 2, p. 478-480, http://dx.doi.org/10.1111/nph.14390.

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Year Published: 2017

Influence of repeated prescribed fire on tree growth and mortality in Pinus resinosa forests, northern Minnesota

Prescribed fire is widely used for ecological restoration and fuel reduction in fire-dependent ecosystems, most of which are also prone to drought. Despite the importance of drought in fire-adapted forests, little is known about cumulative effects of repeated prescribed burning on tree growth and related response to drought. Using...

Bottero, Alessandra; D'Amato, Anthony W.; Palik, Brian J.; Kern, Christel C.; Bradford, John B.; Scherer, Sawyer S.
Bottero, A., D’Amato, A.W., Palik, B.J., Kern, C.C., Bradford, J.B., and Scherer, S.S., 2017, Influence of repeated prescribed fire on tree growth and mortality in Pinus resinosa forests, northern Minnesota: Forest Science, v. 63, no. 1, p. 94-100, http://dx.doi.org/10.5849/forsci.16-035 and https://www.researchgate.net/profile/Alessandra_Bottero/publication/311820299_Influence_of_repeated_prescribed_fire_on_tree_growth_and_mortality_in_Pinus_resinosa_forests_northern_Minnesota/links/585bf57e08ae329d61f2e3e5.pdf.

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Year Published: 2017

The response of arid soil communities to climate change: Chapter 8

Arid and semiarid ecosystems cover approximately 40% of Earth’s terrestrial surface and are present on each of the planet’s continents [1]. Drylands are characterized by their aridity, but there is substantial geographic, edaphic, and climatic variability among these vast ecosystems, and these differences underscore substantial variation in...

Steven, Blaire; McHugh, Theresa Ann; Reed, Sasha C.
Steven, B., McHugh, T.A., Reed, S. 2017, The response of arid soil communities to climate change, in Blaire, S., and Antoninka, A.J., eds., The biology of arid soils—Life in extreme environments: De Gruyter, Berlin/Boston.

Nine USGS Science Centers are administered by the Pacific Regional office, which is headquartered in Sacramento, California.