Publications
Below are publications associated with the Southwest Biological Science Center's research.
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Filter Total Items: 1332
Reproductive output and clutch phenology of female Agassiz's desert tortoises (Gopherus agassizii) in the Sonoran Desert region of Joshua Tree National Park
Agassiz's desert tortoise (Gopherus agassizii) reaches the southern edge of its range in the Sonoran Desert of California. The reproductive ecology of this wideranging species is understudied here compared to populations in the adjacent Mojave Desert. Understanding potential geographic variation in reproductive ecology is important for effective management of conservation-reliant species like G. a
Authors
Jeffrey E. Lovich, Shellie R. Puffer, Mickey Agha, Joshua R. Ennen, Kathie Meyer-Wilkins, Laura A. Tennant, Amanda L Smith, Terence R. Arundel, Kathleen D. Brundige, Michael S. Vamstad
Forest floor and mineral soil respiration rates in a northern Minnesota red pine chronosequence
We measured total soil CO2Â efflux (RS) and efflux from the forest floor layers (RFF) in red pine (Pinus resinosaAit.) stands of different ages to examine relationships between stand age and belowground C cycling. Soil temperature and RSÂ were often lower in a 31-year-old stand (Y31) than in 9-year-old (Y9), 61-year-old (Y61), or 123-year-old (Y123) stands. This pattern was most apparent during warm
Authors
Matthew Powers, Randall Kolka, John B. Bradford, Brian J. Palik, Martin Jurgensen
Temperate and tropical forest canopies are already functioning beyond their thermal thresholds for photosynthesis
Tropical tree species have evolved under very narrow temperature ranges compared to temperate forest species. Studies suggest that tropical trees may be more vulnerable to continued warming compared to temperate species, as tropical trees have shown declines in growth and photosynthesis at elevated temperatures. However, regional and global vegetation models lack the data needed to accurately repr
Authors
Alida C. Mau, Sasha C. Reed, Tana E. Wood, Molly A. Cavaleri
Infrared heater system for warming tropical forest understory plants and soils
The response of tropical forests to global warming is one of the largest uncertainties
in predicting the future carbon balance of Earth. To determine the likely effects of elevated
temperatures on tropical forest understory plants and soils, as well as other
ecosystems, an infrared (IR) heater system was developed to provide in situ warming
for the Tropical Responses to Altered Climate Experiment
Authors
Bruce A. Kimball, Aura M. Alonso-RodrĂguez, Molly A. Cavaleri, Sasha C. Reed, Grizelle González, Tana E. Wood
Isotopic evidence that nitrogen enrichment intensifies nitrogen losses to the atmosphere from subtropical mangroves
Nitrogen (N) enrichment can have large effects on mangroves’ capacity to provide critical ecosystem services by affecting fundamental functions such as N cycling and primary productivity. However, our understanding of excess N input effects on N cycling in mangroves remains quite limited. To advance our understanding of how N enrichment via water or air pollution affects mangroves, we evaluated wh
Authors
Carla Roberta Gonçalves Reis, Sasha C. Reed, Rafael Silva Oliveira, Gabriela Bielefeld Nardoto
Life history with emphasis on geographic variation
Every organism is defined by a set of vital rates that evolve to enhance lifetime reproductive fitness and survival of individuals and their progeny. These traits vary due to the complex but sometimes predictable interactions between individuals, populations and their environments. Collectively, these attributes are referred to as life history traits and include age and size of maturity, longevity
Authors
Jeffrey E. Lovich, J. Whitfield Gibbons, Kathryn Greene
Taxonomy: A history of controversy and uncertainty
No abstract available.Â
Authors
Jeffrey E. Lovich, Kristen Hart
Global conservation status of turtles and tortoises (order Testudines)
We present a review and analysis of the conservation status and International Union for Conservation of Nature (IUCN) threat categories of all 360 currently recognized species of extant and recently extinct turtles and tortoises (Order Testudines). Our analysis is based on the 2018 IUCN Red List status of 251 listed species, augmented by provisional Red List assessments by the IUCN Tortoise and Fr
Authors
Anders G.J. Rhodin, Craig B. Stanford, Peter Paul van Dijk, Carla Eisemberg, Luca Luiselli, Russell A. Mittermeier, Rick Hudson, Brian D. Horne, Eric Goode, Gerald Kuchling, Andrew Walde, Ernst H. W. Baard, Kristin H. Berry, Albert Bertolero, Torsten E. G. Blanck, Roger Bour, Kurt A. Buhlmann, Linda J. Cayot, Sydney Collett, Andrea Currylow, Indraneil Das, Tomas Diagne, Joshua R. Ennen, Germán Forero-Medina, Matthew G. Frankel, Uwe Fritz, Gerardo GarcĂa, J. Whitfield Gibbons, Paul M. Gibbons, Gong Shiping, Joko Guntoro, Margaretha D. Hofmeyr, John B. Iverson, A. Ross Kiester, Michael Lau, Dwight P. Lawson, Jeffrey E. Lovich, Edward O. Moll, Vivian P. Páez, Rosalinda Palomo-Ramos, Kalyar Platt, Steven G. Platt, Peter C. H. Pritchard, Hugh R. Quinn, Shahriar Caesar Rahman, Soary Tahafe Randrianjafizanaka, Jason Schaffer, Will Selman, H. Bradley Shaffer, Dionysius S. K. Sharma, Shi Haitao, Shailendra Singh, Ricky Spencer, Kahleana Stannard, Sarah Sutcliffe, Scott Thomson, Richard C. Vogt
Quantifying postfire aeolian sediment transport using rare earth element tracers
Grasslands, which provide fundamental ecosystem services in many arid and semiarid regions of the world, are undergoing rapid increases in fire activity and are highly susceptible to postfire-accelerated soil erosion by wind. A quantitative assessment of physical processes that integrates fire-wind erosion feedbacks is therefore needed relative to vegetation change, soil biogeochemical cycling, ai
Authors
David Dukes, Howell B. Gonzales, Sujith Ravi, David E. Grandstaff, R. Scott Van Pelt, Junran Li, Guan Wang, Joel B. Sankey
Agriculture
Agricultural production is a fundamental activity conducted on 45% of the U.S. land area, 55% of Mexico’s land area, and 7% of Canada’s land area (World Bank 2016). Because of this vast spatial extent and the strong role that land management plays in how agricultural ecosystems function, agricultural lands and activities represent a large portion of the North American carbon budget. Accordingly, i
Authors
Alexander N. Hristov, Jane M. F. Johnson, Charles W. Rice, Molly E. Brown, Richard T. Conant, Stephen J. Del Grosso, Noel P. Gurwick, C. Alan Rotz, Upendra M. Sainju, R. Howard Skinner, Tristram O. West, Benjamin R. K. Runkle, Henry Janzen, Sasha C. Reed, Nancy Cavallaro, Gyami Shrestha
Population expansion of Humpback chub in western Grand Canyon and hypothesized mechanisms
Humpback chub, Gila cypha, is an endangered warm water fish endemic to the Colorado River basin of southwestern North America. In Grand Canyon National Park, cold hypolimnetic water-release temperatures from Glen Canyon Dam have largely precluded successful spawning and recruitment of humpback chub in the mainstem Colorado River. Therefore, the species has utilized the warmer, more saline, and fre
Authors
David R. VanHaverbeke, Dennis M. Stone, Michael Dodrill, Kirk L. Young, Michael J. Pillow
Case studies of capacity building for biodiversity monitoring
Monitoring the status and trends of species is critical to their conservation and management. However, the current state of biodiversity monitoring is insufficient to detect such for most species and habitats, other than in a few localised areas. One of the biggest obstacles to adequate monitoring is the lack of local capacity to carry out such programs. Thus, building the capacity to do such moni
Authors
Dirk S. Schmeller, Christos Arvanitidis, Monika Böhm, Neil Brummitt, Eva Chatzinikolaou, Mark John Costello, Hui Ding, Michael J. Gill, Peter Haase, Romain Juillard, Jaime GarcĂa-Moreno, Nathalie Pettorelli, Cui Peng, Corinna Riginos, Ute Schmiedel, John P. Simaika, Carly Waterman, Jun Wu, Haigen Xu, Jayne Belnap