Publications
Below are publications associated with the Southwest Biological Science Center's research.
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Filter Total Items: 1332
Climate change reduces extent of temperate drylands and intensifies drought in deep soils
Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in extent and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands. Uncertainty in the future of tropical and subtrop
Authors
Daniel R. Schlaepfer, John B. Bradford, William K. Lauenroth, Seth M. Munson, Britta Tietjen, Sonia A. Hall, Scott D. Wilson, Michael C. Duniway, Gensuo Jia, David A. Pyke, Ariuntsetseg Lkhagva, Khishigbayar Jamiyansharav
Ecosystem implications of conserving endemic versus eradicating introduced large herbivores in the Galapagos Archipelago
Restoration of damaged ecosystems through invasive species removal and native species conservation is an increasingly common practice in biodiversity conservation. Estimating the degree of ecosystem response attributable specifically to eradication of exotic herbivores versus restoration of native herbivores is often difficult and is complicated by concurrent temporal changes in other factors, esp
Authors
Guillaume Bastille-Rousseau, James P. Gibbs, Karl Campbell, Charles B. Yackulic, Stephen Blake
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 from the dam result in a river that is generally uns
Authors
William R. Persons, David R. Van Haverbeke, Michael J. Dodrill
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 images at varying spatial resolutions. These issues ar
Authors
Hamideh Nouri, Sharolyn Anderson, Paul Sutton, Simon Beecham, Pamela L. Nagler, Christopher J. Jarchow, Dar A. Roberts
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 Colorado River in Marble Canyon. The model employs thed
Authors
Laura V. Alvarez, Mark W. Schmeeckle, Paul E. Grams
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 Canyon Dam Long-Term Experimental and Management Plan
Authors
Scott P. Vanderkooi, Theodore A. Kennedy, David J. Topping, Paul E. Grams, David L. Ward, Helen C. Fairley, Lucas S. Bair, Joel B. Sankey, Charles B. Yackulic, John C. Schmidt
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 settling velocities calculated using results from severa
Authors
Michael V. W. Cuttler, Ryan J. Lowe, James L. Falter, Daniel D. Buscombe
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 georectification of sonar echograms are presented, b
Authors
Daniel D. Buscombe
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 boundaries of the Coachella Valley Multiple Species H
Authors
Jeffrey E. Lovich, Taylor Edwards, Brian Kreiser, Shellie R. Puffer, Mickey Agha
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 in predicting extinctions due to climate change. Pre
Authors
Barry Sinervo, Rafael A. Lara Reséndiz, Donald B. Miles, Jeffrey E. Lovich, Joshua R. Ennen, Johannes Müller, Robert D. Cooper, Philip C. Rosen, Joseph A. E. Stewart, Juan Carlos Santos, Jack W. Sites, Paul Gibbons, Eric Goode, L. Scott Hillard, Luke Welton, Mickey Agha, Gabriel Caetano, Mercy Vaughn, Cristina Meléndez Torres, Héctor Gadsden, Gamaliel Casteñada Gaytán, Patricia Galina-Tessaro, Fernando I. Valle Jiménez, Jorge H. Valdez-Villavicencio, Norberto Martínez Méndez, Guillermo Woolrich Piña, Victor Luja Molina, Aníbal Díaz de la Vega Pérez, Diego M. Arenas Moreno, Saúl Domínguez Guerrero, Natalia Fierro, Scott Butterfield, Michael Westpha, Raymond B. Huey, William Mautz, Víctor Sánchez-Cordero, Fausto R. Méndez de la Cruz
Human land-use and soil change
Soil change refers to the alteration of soil and soil properties over time in one location, as opposed to soil variability across space. Although soils change with pedogensis, this chapter focuses on human caused soil change. Soil change can occur with human use and management over long or short time periods and small or large scales. While change can be negative or positive; often soil change i
Authors
Skye A. Wills, Candiss O. Williams, Michael C. Duniway, Jessica Veenstra, Cathy Seybold, DeAnn Pressley
Effectiveness of environmental flows for riparian restoration in arid regions: A tale of four rivers
Environmental flows have become important restoration tools on regulated rivers. However, environmental flows are often constrained by other demands within the river system and thus typically are comprised of smaller water volumes than the natural flows they are meant to replace, which can limit their functional efficacy. We review environmental flow programs aimed at restoring riparian vegetation
Authors
Edward P. Glenn, Pamela L. Nagler, Patrick B. Shafroth, Christopher Jarchow