Publications
Below are publications associated with the Southwest Biological Science Center's research.
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Filter Total Items: 1332
Channel narrowing by inset floodplain formation of the lower Green River in the Canyonlands region, Utah
The lower Green River episodically narrowed between the mid-1930s and present day through deposition of new floodplains within a wider channel that had been established and/or maintained during the early twentieth century pluvial period. Comparison of air photos spanning a 74-yr period (1940−2014) and covering a 61 km study area shows that the channel narrowed by 12% from 138 ± 3.4 m to 122 ± 2.1
Authors
Alexander E. Walker, Johnnie N. Moore, Paul Grams, David Dean, John C. Schmidt
Low stand density moderates growth declines during hot droughts in semi-arid forests
Increasing heat and aridity in coming decades is expected to negatively impact tree growth and threaten forest sustainability in dry areas. Maintaining low stand density has the potential to mitigate the negative effects of increasingly severe droughts by minimizing competitive intensity.However, the direct impact of stand density on the growing environment (i.e. soil moisture), and the specific d
Authors
Caitlin M. Andrews, Anthony W. D'Amato, Shawn Fraver, Brian Palik, Michael A. Battaglia, John B. Bradford
Altered climate leads to positive density‐dependent feedbacks in a tropical wet forest
Climate change is predicted to result in warmer and drier Neotropical forests relative to current conditions. Negative density‐dependent feedbacks, mediated by natural enemies, are key to maintaining the high diversity of tree species found in the tropics, yet we have little understanding of how projected changes in climate are likely to affect these critical controls. Over 3 years, we evaluated t
Authors
Armando Barreto-Muñoz, Aura M. Alonso-Rodríguez, Laura Aldrich-Wolfe, Molly A. Cavaleri, Sasha C. Reed, Tana E Wood
Soil water availability shapes species richness in mid-latitude shrub steppe plant communities
QuestionsEcological communities are controlled by multiple, interacting abiotic and biotic factors that influence the distribution, abundance, and diversity of species. These processes jointly determine resource availability, resource competition, and ultimately species richness. For many terrestrial ecosystems in dryland climates, soil water availability is the most frequent limiting resource for
Authors
Samuel E. Jordan, Kyle A. Palmquist, John B. Bradford, William K. Lauenroth
Soil biogeochemical responses of a tropical forest to warming and hurricane disturbance
Tropical forests represent 50% of the planets species and play a disproportionately large role in determining climate due to the vast amounts of carbon they store and exchange with the atmosphere. Currently, disturbance patterns in tropical ecosystems are changing due to factors such as increased land use pressure and an occurrence of hurricanes. At the same time, these regions are expected to exp
Authors
Sasha C. Reed, Robin H. Reibold, Molly A. Cavaleri, Aura M. Alonso-Rodríguez, Megan E. Berberich, Tana E. Wood
A primer of fishery studies in Grand Canyon: The nonnative fish removal story
Globally, rivers have become the most altered of ecosystems, chiefly due to pollution, water withdrawals, and dams that have modified their former function, and led to large and unforeseen impacts, particularly for fish populations. Extensive research is directed at studying impacts of dams because they sever migration routes and change the physical template (flow, temperature, and sediment and or
Authors
Mike Yard
The right trait in the right place at the right time: Matching traits to environment improves restoration outcomes
(Munson) The challenges of restoration in dryland ecosystems are growing due to a rise in anthropogenic disturbance and increasing aridity. Plant functional traits are often used to predict plant performance and can offer a window into the potential outcomes of restoration efforts across environmental gradients. We tracked 15 years of seeding outcomes across 150 sites on the Colorado Plateau, a co
Authors
Kathleen R. Balazs, Andrea T. Kramer, Seth M. Munson, Nora Talkington, Shannon Still, Bradley J. Butterfield
A need for speed in Bayesian population models: A practical guide to marginalizing and recovering discrete latent states
Bayesian population models can be exceedingly slow due, in part, to the choice to simulate discrete latent states. Here, we discuss an alternative approach to discrete latent states, marginalization, that forms the basis of maximum likelihood population models and is much faster. Our manuscript has two goals: 1) to introduce readers unfamiliar with marginalization to the concept and provide worked
Authors
Charles B. Yackulic, Michael J. Dodrill, Maria C. Dzul, Jamie S. Sanderlin, Janice A. Reid
Practices of biological soil crust rehabilitation in China: Experiences and challenges
Biological soil crusts (biocrusts) are a central component of dryland ecosystems. However, they are highly vulnerable to disturbance and natural recovery may be slow. Therefore, finding ways to enhance the reestablishment of biocrusts after disturbance has been of great interest to researchers. This article provides a review of the laboratory cultivation and field inoculations of biocrust material
Authors
Xiaobing Zhou, Yunge Zhao, Jayne Belnap, Bingchang Zhang, Chongfeng Bu, Yuanming Zhang
Assessment of population genetics and climatic variability can refine climate‐informed seed transfer guidelines
Restoration guidelines increasingly recognize the importance of genetic attributes in translocating native plant materials (NPMs). However, when species‐specific genetic information is unavailable, seed transfer guidelines use climate‐informed seed transfer zones (CSTZs) as an approximation. While CSTZs may improve how NPMs are developed and/or matched to restoration sites, they overlook genetic f
Authors
Robert Massatti, Robert K. Shriver, Daniel E. Winkler, Bryce A. Richardson, John B. Bradford
Bridging the research-management gap: Landscape ecology in practice on public lands in the western United States
The field of landscape ecology has grown and matured in recent decades, but incorporating landscape science into land management decisions remains challenging. Many lands in the western United States are federally owned and managed for multiple uses, including recreation, conservation, and energy development. We argue for stronger integration of landscape science into the management of these publi
Authors
Sarah K. Carter, David Pilliod, Travis S. Haby, Karen L. Prentice, Cameron L. Aldridge, Patrick J. Anderson, Zachary H. Bowen, John B. Bradford, Samuel A. Cushman, Joseph C. DeVivo, Michael C. Duniway, Ryan S. Hathaway, Lisa Nelson, Courtney A. Schultz, Rudy Schuster, E. Jamie Trammell, Jake Weltzin
What's in the hump of the humpback chub?
The function of the nuchal hump on adult humpback chub (Gila cypha) has been the subject of longtime conjecture. Hypotheses about the purpose of the hump range from it being a feature that confers hydrodynamic advantages in swift water to speculation about how the hump may have reduced predation vulnerability to Colorado pikeminnows (Ptychocheilus lucius). We used comparative histology of the head
Authors
David Ward, Michael B. Ward