Jump to: Travis Bean | Julio Betancourt | Jan Bowers | Brian Enquist | Travis Huxman | Paul Martin | Waite Osterkamp | Jay Quade | Ray Turner | Larry Venable | Robert Webb
Travis Bean currently spearheads the Desert Laboratory's effort to control buffelgrass in Southern Arizona. His work is focused on raising awareness about buffelgrass among the public, policy makers, and land managers, as well as on coordination and implementation of actual on-the-ground control of buffelgrass on Tumamoc Hill and in other parts of the Tucson Basin.
Travis' Curriculum Vitae
contains more detailed information about his current and past
research.
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Julio Betancourt studies ecosystem and watershed responses to climate variability on different temporal and spatial scales. Along with his colleagues and students, Julio has contributed to networks of rodent midden and tree ring data in the Americas. He has designed, tested and/or applied a wide variety of approaches, including historical documents and photographs, instrumental hydrological and climatic data, long-term vegetation plots, tree rings, stable isotopes, ancient DNA, biometrical measurements, alluvial stratigraphy, and even ice cores to reconstruct the past.
Julio's Curriculum Vitae
contains more detailed information about his current and past
research.
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Janice Bowers studies the effects of climatic variability on the reproduction, establishment, and survival of woody desert plants such as foothill paloverde, barrel cactus, Engelmann prickly pear, and triangle-leaf bursage. She has also has written several historical accounts of the Desert Laboratory, including a biography of the plant ecologist Forrest Shreve and biographical sketches of other researchers at the original Desert Laboratory. During the past decade, Janice Bowers has undertaken numerous investigations on Tumamoc Hill, including: (1) dieback of foothill paloverde following severe drought, (2) between-year variability in flower, fruit, and seed production of Engelmann prickly pear, fishhook cactus, and barrel cactus, (3) methods of using plant size and annual growth rates to age-date prickly pear and barrel cactus, (4) population dynamics of foothill paloverde, Engelmann prickly pear and barrel cactus, (5) rainfall patterns that trigger natural germination of common desert shrubs and cacti, and (6) longevity of seeds in the soil. She has gathered new information on the longevity, survivorship, and fecundity of common desert plants, filling gaps in our knowledge of their life history and challenging preconceived ideas about their ecology. The plants that she studies are intricately woven into the fabric of the Sonoran Desert. Some are vitally important to insects, birds, and mammals as seasonal sources of pollen, nectar, and seeds. Others function as nurse plants, hiding seeds and seedlings from hungry animals and protecting tender shoots from heat and frost. As global warming continues, knowing how these species respond to climatic variability will help us predict the future of Sonoran Desert plant and animal communities.
Jan's Curriculum Vitae
contains more detailed information about her current and past
research.
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Brian Enquist is a plant ecologist who studies
how functional and physical constraints at
the level of the individual influence larger scale
ecological and evolutionary patterns. Further details of
his interests and research, as well as his Curriculum Vitae,
are included on
his laboratory web site (external link).
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Travis Huxman is a plant physiologial ecologist who
is interested in plant evolution and global change.
Further details of his research are included on
his web site (external link).
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Paul Martin is Emeritus Professor of Geosciences at the Desert Laboratory of the University of Arizona in Tucson. For more than forty years Dr. Martin has investigated Pleistocene biotic changes in arid regions. He has studied the biogeography of eastern Mexico, the Pleistocene fossil pollen record of Arizona, and the potential for fossil packrat middens to reveal climatic changes.
Paul's Curriculum Vitae
contains more detailed information about his current and past
research.
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Waite Osterkamp, a geomorphologist, is interested in the factors that govern landscape stability, from hillslopes to bottomlands. He studies the nature and rate of recovery of these surfaces from natural and anthropogenic disturbance, and the role that vegetation plays in this recovery. This information can be used to plan engineering works and to manage riparian settings. For example, maintaining the integrity of channel islands at Deer Flat National Wildlife Refuge is a key issue in the adjudication of Snake River streamflow. In many river systems, these islands are ever changing, but in the Snake River, some are relics of the Bonneville Flood 14,500 years ago, and others appear to be terrace remnants of sand and silt that was deposited along the river periodically during the last 10,000 years in response to alpine glacial episodes. Waite's role is to identify rates of water release adequate for power generation and irrigation, while maintaining the integrity of the unusual habitat provided by the channel islands. Waite also has investigated processes involved in the origin and development of playa-lake basins in the Southern High Plains. His current research includes the evolution of armored hillslopes, the geomorphic and hydrologic effects of transmission loss to arid-zone streamflow, and the processes of sediment storage and revegetation that follow catastrophic floods.
Waite's Curriculum Vitae
contains more detailed information about his current and past
research.
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Jay Quade is a soils/stable isotope geochemist. Earlier in his career, Jay helped develop models, now widely adopted, linking carbon isotopes from soil carbonates to soil respiration, vegetation and atmospheric CO2. He applied these models to infer a pedogenic origin for calcite veins at Yucca Mountain, a controversy in its licensing for burial of nuclear waste. Jay and his colleagues have also documented the late Miocene expansion of grasses from Pakistan to Argentina. This global event may be linked to mountain building, weathering, climate change and possibly decreasing atmospheric CO2. Jay, PhD candidate Lois Roe, and MS student Tank Ojha are now applying strontium isotopes from shells and soil carbonates to reconstruct erosional unroofing of the Nepal Himalayas during the past 12 million years. Jay, and PhD candidates Bill Phillips and Nat Lifton are using cosmogenic isotopes to date a variety of geomorphic surfaces from the Channel Scablands in the Columbia Plateau to the Himalayas. For her thesis, Lois Roe is developing analytical methods for studying biogenic phosphates as a key to understanding the physiological evolution of early whales.
Jay's Curriculum Vitae
contains more detailed information about his current and past
research.
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Ray Turner is a plant ecologist whose interest has focused mainly on vegetation change in arid areas of North American and Africa. As part of the vegetation change theme, he has studied saguaro cactus and palo verde demography, changes in riparian plant communities, and climatic controls of contemporary plant distributions. Another facet of his vegetation change studies involves old landscape photographs that, when matched exactly, provide detailed insights into the kinds of changes that transpire under various climatic and cultural influences. He has conducted several studies at the Desert Laboratory, beginning in 1956.
Ray's Curriculum Vitae
contains more detailed information about his current and past
research.
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Larry Venable studies plant population and community
dynamics and plant reproductive ecology. He works
on the population dynamics of desert winter annual plants.
Further details of his research are included on
his web site (external link).
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Bob Webb is a geomorphologist/soil scientist/hydrologist/ecologist with a
background in civil engineering. Early in
his career, he edited a book and wrote several articles on the effect of
off-road vehicles on desert soils. This work led to post-disturbance studies
of soil recovery and plant succession in ghost towns. In the
Mojave Desert, he found that plant succession indeed occurs in deserts, and
discovered the value of repeat photography and packrat midden research (both
he and Jay Quade have collected stick-nest rat middens
in Australia). Bob has reconstructed paleofloods and historic
channel changes in the Colorado River Basin, and was among the first
to quantify the link between climate variability and flood frequency in
southern Arizona. In 1984, he floated the Colorado River to study debris
flows and their influence on formation of Grand
Canyon rapids. He has floated the Grand Canyon many times since to
estimate the magnitude and frequency of debris flows, as well as to
document vegetation change. These river trips, justified by the Glen
Canyon Environmental Impact Studies, culminated in a recent UA press
book and several monographs that rely heavily on repeat
photography. Peter Griffiths, who worked with Bob in the Grand Canyon,
is now on the permanent USGS staff at the Desert Lab.
Bob Webb's National Research Program Project Bibliography
details more of his research. You can also read more about Bob's work at the
Riparian Vegetation Change page and the
Mojave Desert Ecosystem Project page.
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