Publications
Below are publications associated with the Southwest Biological Science Center's research.
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Filter Total Items: 1311
Distance sampling for Sonoran Desert tortoises
We used line transects and distance sampling in combination with radiotelemetry to estimate density of a desert tortoise (Gopherus agassizii) population in the Rincon Mountains near Tucson, Arizona, USA, as part of a long-term study evaluating the impact of urban development on tortoises. During 2000, 34 1-km transects were each sampled twice in the 368.5-ha study area. We observed 46 tortoises wi
Authors
Don E. Swann, Roy C. Averill-Murray, Cecil R. Schwalbe
Fire ecology of the Sonoran desert tortoise
No abstract available.
Authors
Todd C. Esque, Alberto Burquez Montijo, Cecil R. Schwalbe, Thomas R. Van Devender, Pamela J. Anning, Michelle J. Nijhuis
Experimental flood effects on the limnology of Lake Powell Reservoir, southwestern USA
In the spring of 1996, a nine-day test flood from Glen Canyon Dam involved the deepest and largest hypolimnetic withdrawals from the penstocks and the river outlet works (ROW) since 1986, interacting with ongoing hydrodynamic and stratification patterns to enhance freshening of the hypolimnion of Lake Powell reservoir and its tailwaters. Prior to the test flood, a six-year drought had produced a p
Authors
Susan J. Hueftle, Lawrence E. Stevens
Soil biota in an ungrazed grassland: Response to annual grass (Bromus tectorum) invasion
Bromus tectorum is an exotic annual grass that currently dominates many western U.S. semi-arid ecosystems, and the effects of this grass on ecosystems in general, and soil biota specifically, are unknown. Bromus recently invaded two ungrazed and unburned perennial bunchgrass communities in southeastern Utah. This study compared the soil food-web structure of the two native grassland associations (
Authors
Jayne Belnap, Susan L. Phillips
Exotic plant invasion alters nitrogen dynamics in an arid grassland
The introduction of nonnative plant species may decrease ecosystem stability by altering the availability of nitrogen (N) for plant growth. Invasive species can impact N availability by changing litter quantity and quality, rates of N2-fixation, or rates of N loss. We quantified the effects of invasion by the annual grass Bromus tectorum on N cycling in an arid grassland on the Colorado Plateau (U
Authors
R.D. Evans, R. Rimer, L. Sperry, Jayne Belnap
Proceedings of the fifth biennial conference of research on the Colorado Plateau
No abstract available.
Authors
K.A. Thomas, M.A. Stuart
Linkage between grain-size evolution and sediment depletion during Colorado River floods
No abstract available.
Authors
David J. Topping, David M. Rubin, Jonathan M. Nelson, Paul J. Kinzel, James P. Bennett
Modeling of flood-deposited sand distributions in a reach of the Colorado River below the Little Colorado River, Grand Canyon, Arizona
A release from Glen Canyon Dam during March-April 1996 was designed to test the
effectiveness with which the riparian environment could be renewed with discharges greatly in excess of the normal powerplant-restricted maximum. Of primary concern was the rebuilding of sand deposits along the channel sides that are important to the flora and fauna along the river corridor and that provide the only
Authors
S.M. Wiele
Proceedings of the third biennial conference of research on the Colorado Plateau
The papers in this volume are contributions from federal, state, and private sector researchers, who have come together to share scientific information with land managers on the Colorado Plateau. This Proceedings is the third in a series of publications that focuses on providing information to land managers on baseline scientific information pertaining to physical, cultural and biological resource
Authors
Elena T. Deshler
"The Great Cataract" - Effects of Late Holocene Debris Flows on Lava Falls Rapid, Grand Canyon National National Park, Arizona
Lava Falls Rapid is the most formidable reach of whitewater on the Colorado River in Grand Canyon and is one of the most famous rapids in the world. Although the rapid was once thought to be controlled by the remnants of lava dams of Pleistocene age, Lava Falls was created and is maintained by frequent debris flows from Prospect Canyon. We used 232 historical photographs, of which 121 were replica
Authors
Robert H. Webb, Theodore S. Melis, Thomas W. Wise, John G. Elliott
Proceedings of the second biennial conference on research in Colorado Plateau National Parks
On 25-28 October 1993 in Flagstaff, Arizona, the National Biological Service Colorado Plateau Research Station (formerly National Park Service Cooperative Park Studies Unit) and Northern Arizona University hosted the Second Biennial Conference of Research on the Colorado Plateau. The conference theme focused on research, inventory, and monitoring on the federal, state, and private lands in the Col
Proceedings of the first biennial conference of research in Colorado Plateau National Parks
The 19 papers in this volume were selected from the 46 presentations given at the First Biennial Conference on Research in Colorado Plateau National Parks. The overall theme for this meeting was research, inventory, and monitoring in National Park Service units on the Colorado Plateau. The conference, held in Flagstaff Arizona, on 22-25 July 1991, was sponsored by the National Park Service Coopera