• A Rapid Biological and Ecological Inventory and Assessment of the Cajon Bonito Watershed, Sonora, Mexico. Part 1: Natural History

      Hunt, Robert; Anderson, Walter; Environmental Studies Program, Prescott College (University of Arizona (Tucson, AZ), 2002-12)
      Cajon Bonito is a perennial stream that drains the western watershed of the Sierra San Luis, Sonora, Mexico. The Sierra San Luis is one of dozens of mountain ranges that are referred to as "sky islands" in a region called the Madrean Archipelago. This landscape exhibits an enormous array of habitats and environments that has made it one of the "mega-biodiverse regions" of the planet. I discuss the unique setting and qualities that make Cajon Bonito one of the most crucial and robust corridors in this sky island archipelago. The information and data that support this conclusion were gathered using a unique set of protocols and field methodologies referred to as Rapid Inventory and Assessment (RAP). I have modified a plant species inventory field method, the variable transect, that was developed for use in the tropics, and I have applied it in the habitats of the Southwest. I have also streamlined the method so that it can be used by a single observer instead of a team. Use of this method in the Cajon Bonito watershed provided me with a quick source of raw, multi-dimensional sampling data. It also provided a wealth of non-quantitative environmental information that reveals the study site's rich natural history.
    • A Rapid Biological and Ecological Inventory and Assessment of the Cajon Bonito Watershed, Sonora, Mexico. PartII: Using the Variable Transect

      Hunt, Robert; Anderson, Walter; Environmental Studies Program, Prescott College (University of Arizona (Tucson, AZ), 2004-12)
      The variable transect is an abbreviated, simplified version of a standard belt transect used in floristic analysis. Developed by the Rapid Assessment Program of Conservation International as part of a suite of "emergency field ecology" methods, it allows scientists to quickly inventory and assess habitats with high biodiversity values that are threatened by imminent development or other human activities. This alternate method was utilized in a study of Cajon Bonito in Sonora, Mexico. Assessment of the variable transect's value as both a convenient qualitative and quantitative tool for field studies and observations in the plant communities of the Southwest is reflected in the resulting database. The method proved flexible enough to vary the suite of floristic data to be sampled with little significant variation in the time spent applying the transect. The relatively quick sampling of flora, combined with easily characterized environmental observations, yields a wealth of information with less effort than most standard field methods.
    • Recalling Famous Arizona Botanists

      Miller, Victor (University of Arizona (Tucson, AZ), 1998-12)
    • Reclamation and Fertilization of Coal Mine Soils in the Southwestern Desert

      Day, A. D.; Ludeke, K. L.; University of Arizona; Ludeke Corporation (University of Arizona (Tucson, AZ), 1986)
      A 5 -year experiment was conducted from 1978 through 1982 on the Black Mesa Coal Mine, Kayenta, Arizona, to study plant species best suited for coal mine reclamation and the effects of fertilizer on selected species. Five plant species were broadcast seeded on coal mine soil (spoils) and unmined soil. Prior to planting, 560 kg /ha of 16-20-0 fertilizer were applied on one -half of each site while the other half received no fertilizer. Immediately after planting, sprinkler irrigation water was applied on all plots, as needed, for the first two years. After two years, fertilizer and irrigation were discontinued on both soil materials and all plant species received only natural rainfall for the following three years. Coal mine soil contained more total soluble salts, nitrogen, potassium, sodium, and organic matter than did unmined soil; however, unmined soil had a higher pH and contained more phosphorous than did coal mine soil. Plant growth measurements were recorded for each plant species in October of each year. In general, plants grew better and produced more forage in unmined soil than they did in coal mine soil. All plant species grew better, yielded more forage, and produced a more satisfactory ground cover when they were fertilized than they did when they were not fertilized. Plant species differed greatly in general growth, forage yield, and percent ground cover within soil materials and within fertilizer treatments. Crested wheatgrass (Agropyron cristaturn L.), western wheatgrass (Agropyron smithii Rydb.), and vernal alfalfa (Medicago sativa L.) grew better, yielded more forage, and produced a more complete ground cover than did Indian ricegrass (Oryzopsis hymenoides Ricker) or fourwing saltbrush (Atriplex canescens Pursh). In general, the reclamation of unmined soil with fertilizer and a combination of natural rainfall and sprinkler irrigation during the first two years and with perennial grasses was more successful than the reclamation of coal mine soil with no fertilizer and with legumes or shrubs in the semiarid environment in the southwestern United States.
    • References

      University of Arizona (Tucson, AZ), 1982
    • Reforestation in Ecuador's Dry Forest

      Agrawal, Anurag A.; Deparment of Entomology, University of California-Davis (University of Arizona (Tucson, AZ), 1996-06)
    • Relict Conifer Forests and Woodlands

      Brown, David E.; Arizona Game and Fish Department (University of Arizona (Tucson, AZ), 1982)
    • A Report on Special Events at the Boyce Thompson Southwestern Arboretum

      Crosswhite, Carol D.; Boyce Thompson Southwestern Arboretum (University of Arizona (Tucson, AZ), 1983)
    • Reproductive Potential and Minimum Reproductive Size of Ferocactus wislizeni (Cactaceae)

      Bowers, Janice E.; U.S. Geological Survey (University of Arizona (Tucson, AZ), 1998-06)
    • Revegetation of Copper Tailing Ponds in the Southwestern U.S.A. with Annual Grasses

      Day, A. D.; Ludeke, K. L. (University of Arizona (Tucson, AZ), 1982-06)
    • Reviews

      University of Arizona (Tucson, AZ), 1979-08
    • Reviews

      University of Arizona (Tucson, AZ), 1980
    • Reviews

      University of Arizona (Tucson, AZ), 1981
    • Reviews

      University of Arizona (Tucson, AZ), 1983
    • Reviews

      University of Arizona (Tucson, AZ), 1979-11
    • Reviews

      University of Arizona (Tucson, AZ), 1981
    • Reviews

      University of Arizona (Tucson, AZ), 1982-01
    • Reviews

      University of Arizona (Tucson, AZ), 1985
    • Reviews

      University of Arizona (Tucson, AZ), 1983
    • Right Under Our Noses: The Role of Floral Scent in Host Detection for a Solitary Specialist Bee

      Carril, Olivia Messinger (University of Arizona (Tucson, AZ), 2014)