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Focuses on the proposal to follow the basin that defines the national boundaries of the Canyonlands National Park in Utah. Background of the establishment of the park; Role of the National Park Conservation Association and other environmentalist in advocating the proposal; Factors involved in the completion of the proposal. Published in National Parks, volume 74, on pages 26 - 31, in 2000.
Categories: Publication; Types: Citation, Journal Citation; Tags: National Parks
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Focuses on the proposal to follow the basin that defines the national boundaries of the Canyonlands National Park in Utah. Background of the establishment of the park; Role of the National Park Conservation Association and other environmentalist in advocating the proposal; Factors involved in the completion of the proposal. Published in National Parks, volume 74, on pages 26 - 31, in 2000.
Categories: Publication; Types: Citation, Journal Citation; Tags: National Parks
Large predators potentially can help shape the structure and functioning of terrestrial ecosystems, yet strong evidence of top-down herbivore limitation has not been widely reported in the scientific literature. Herein we synthesize outcomes of recent tri-trophic cascades studies involving the presence and absence of large predators for five national parks in the western United States, including Olympic, Yosemite, Yellowstone, Zion, and Wind Cave. Historical observations by park biologists regarding woody browse species and recently compiled age structure data for deciduous trees indicate major impacts to woody plant communities by ungulates following the extirpation or displacement of large predators. Declines...
Over 26,100 records of lichens present in 144 U.S. national park units were assembled from various sources into a database and analyzed. Within these 144 park units 2,435 species and 375 genera are reported, representing 63% and 74% of the North American flora, respectively. The park units are located in 41 states and Washington, D.C. The average number of species in a park is 104, but the median is 60, indicating there are many parks with a small number of species and a few with high numbers. Isle Royale National Park has the most species, 611, and twelve parks have only one species reported. The number of records of lichens present ranged from one for 25 parks, to 1,623 for Isle Royale. Physcia aipolia is the...
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During the two years from 24 May 1978 to 7 June 1980, the battery subsystem for the 100-kW peak photovoltaic power system for Natural Bridges National Monument was designed, modified, tested, installed, retested and again modified. The subsystem includes 224 lead-acid (with calcium alloy) cells, hydrogen recombiners, an air-lift pump system and electrolyte level indicators. Problems and solutions related to these subsystem components are discussed. Further details concerning the battery selection, design, tests and performance throughout the battery's life are also included. Published by Massachusetts Institute of Technology, Lincoln Laboratory, in 1981.
The long-term preservation of national park ecosystems requires scientific knowledge about populations, communities, and the ecological processes upon which sustainable ecosystems depend. Unfortunately, national parks in the United States have a well-documented history of indifference, if not hostility, to the support of basic research. Numerous external reviews have criticized the lack of institutional support for science, blaming it in large part on the traditional emphasis of the National Park Service (NPS) on scenery and tourism management. However, recent efforts to improve the support for science in the U.S. national parks have been most encouraging. These include a long-sought Congressional mandate to support...
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Seasonal forages of desert bighorn sheep (Ovis canadensis nelsoni) were analyzed for dry matter, crude protein, in vitro digestibility, and cell wall content. Qualitative nutrient intake was estimated by combining chemical analyses with diet-composition data. Composite diets were also analyzed for the above parameters as well as for phosphorus and calcium. Dietary quality generally declined from spring to winter. Diet digestibility was good to excellent year-round, indicating that desert bighorn were receiving adequate energy. Protein levels were high in spring but were probably deficient for lactating ewes and young lambs in summer and fall. Diets were deficient in phosphorus in all seasons. Forbs had higher protein...
    map background search result map search result map Application, sizing, testing and performance of the photovoltaic battery subsystem at Natural Bridges National Monument, Utah Completing Canyonlands Seasonal nutrition of desert Bighorn sheep in Canyonlands National Park, Utah Application, sizing, testing and performance of the photovoltaic battery subsystem at Natural Bridges National Monument, Utah Completing Canyonlands Seasonal nutrition of desert Bighorn sheep in Canyonlands National Park, Utah