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Articles 13261 - 13290 of 16015
Full-Text Articles in Entire DC Network
Measuring Species Diversity On Revegetated Surface Mines: An Evaluation Of Techniques, United States Department Of Agriculture, Forest Service
Measuring Species Diversity On Revegetated Surface Mines: An Evaluation Of Techniques, United States Department Of Agriculture, Forest Service
Mines and Mineral Resources
This report reviews the three most commonly used techniques for measuring species diversity in plant communities: (1) diversity indices, (2) rank correlation tests, and (3) similarity indices. The author discusses the suitability of each technique for assessing species diversity on mined land and evaluates the most often used indices, test statistics, or coefficients of each technique. Applications of the Shannon-Weiner diversity index, Spearman's rank order correlation coefficient, Motyka and others' and Bray and Curtis' version of Sorensen's similarity index, and Spatz' version of Jaccard's index for assessing mined land species diversity are presented in the appendix.
Internal Filters : Prospects For Uv-Acclimation In Higher Plants, Martyn M. Caldwell, Ronald Robberecht, Stephan D. Flint
Internal Filters : Prospects For Uv-Acclimation In Higher Plants, Martyn M. Caldwell, Ronald Robberecht, Stephan D. Flint
Green Canyon Environmental Research Area, Logan Utah
Wavelength-selective absorption of solar radiation within plant leaves allows penetration of visible radiation to the chloroplats, while removing much of the damaging ultraviolet-B radiation. Flavonoids are important in this wavelength-selective absorption. Induction of flavonoid synthesis by solar radiation, and specifically by UV-B radiation, is discussed as this relates to the potential acclimation of plants to enhanced solar UV-B radiation that would result from stratospheric ozone reduction.
The Effects Of Ultraviolet-B Radiation On Plant Competition In Terrestrial Ecosystems, Warren G. Gold, Martyn M. Caldwell
The Effects Of Ultraviolet-B Radiation On Plant Competition In Terrestrial Ecosystems, Warren G. Gold, Martyn M. Caldwell
Green Canyon Environmental Research Area, Logan Utah
Evidence regarding the interaction of ultraviolet-B radiation and plant competition in terrestrial ecosystems is examined. The competitive interactions of some species pairs were affected even by ambient solar UV-B radiation when compared to control pairs grown without UV-B. Also, the total shoot biomass of these species pairs was depressed under ambient UV-B. Relatively large increases in UV-B radiation altered the competitive interactions of some species pairs grown in pots under field conditions, but did not affect the total shoot biomass production of those pairs. Recent field experiments have examined the competitive interactions of wheat and wild oat under a simulated …
Morphometry Of Meat By Scanning Light Microscopy, H. J. Swatland
Morphometry Of Meat By Scanning Light Microscopy, H. J. Swatland
Food Structure
Morphometric data can be collected from meat by using a scanning stage and a photometer, both controlled by a microcomputer. The passive counting of connective tissue boundaries is g1ven as an example to show that enumerative data may be biassed by the ratio of the width of the subject of measurement to the projected diameter of the photometer aperture. In a second example, the scanning stage is actively directed by the observer and is used to map the radial distribution of succinate dehydrogenase (SOH) activity in different histochemical types of muscle fibers. This is accomplished by the arbitrary fitting by …
Field Spectroscopy In The Food Production Chain, E. J. Brach
Field Spectroscopy In The Food Production Chain, E. J. Brach
Food Structure
This paper reviews the application of field spectroscopy in the food production chain, particularly how field spectroscopy aids research and production of agricultural crops , and helps to understand the process of converting these crops into food.
The review discusses the nondestructive application of field spectroscopy such as ultraviolet, reflective , visible, near infrared and fluorescence techniques using conventional or laser light sources, to determine qualitative and quantitative properties of agricultural crops and produce.
Field spectroscopy can provide data on soil constituents and moisture, crop maturity, crop vigor, crop health, variety, variety within crops , and protein and moisture content …
An Economic Evaluation Of Benefits And Costs Of Maintaining Instream Flows, Rangesan Narayanan, Dean T. Larson, A. Bruce Bishop, Parvaneh Amirfathi
An Economic Evaluation Of Benefits And Costs Of Maintaining Instream Flows, Rangesan Narayanan, Dean T. Larson, A. Bruce Bishop, Parvaneh Amirfathi
Reports
Instream flows enhance recreation, hydropower, fish and wildlife maintenance, and riverine ecosytems. Each use has water requirements that vary over time in unique patterns. The determination of the overall instream requirement at any given time must be considered in competition with the demand for municipal and agricultural uses. Two obstacles to integrating instream uses into the appropriation system of water law are difficulty in satisfying the legal requirements of an appropriation for a public use and the fact that instream flow uses are considered more "environmental" than "economic" in character. The extreme options for allocating flow between these user groups …
Aspen Management Guidelines For The Grand Mesa, Uncompahgre And Gunnison National Forest, Aspen Management Task Force
Aspen Management Guidelines For The Grand Mesa, Uncompahgre And Gunnison National Forest, Aspen Management Task Force
Aspen Bibliography
A task force was formed in late April 1983 for the purpose of developing guidelines for Aspen Management on the Grand Mesa, Uncompahgre and Gunnison National Forests.
An Experimental Investigation Of The Effects Of Crude Oil On Two Freshwater Lake Ecosystems, Martin D. Werner, V. Dean Adams, Vincent A. Lamarra
An Experimental Investigation Of The Effects Of Crude Oil On Two Freshwater Lake Ecosystems, Martin D. Werner, V. Dean Adams, Vincent A. Lamarra
Reports
Responses of two freshwater lake ecosystems of the Intermountain West to crude oil impaction were investigated. The research was conducted in two phases; in the first phase effects of crude oil were studied on an ecosystem established in three phase laboratory microcosms (gaseous-aqueous-sediment), which simulated the natural lakes. Notable responses of the microcosm ecosystem to oil impaction included: an increased oxygen demand by the biological community, nutrient immobilization, a reduction in plant biomass accumulation and a heterotrophically dominated ecosystem. The increased availability of biologically degradable reduced carbon (i.e., the oil) and nutrient immobilization, rather than toxic effects of oil on …
Effects Of Cadmium On Streams And Irrigated Agriculture In The Presence And Absence Of Oil Shale Leachate, Douglas A. Selby, Jean M. Ihnat, Fredrick J. Post, Jay J. Messer
Effects Of Cadmium On Streams And Irrigated Agriculture In The Presence And Absence Of Oil Shale Leachate, Douglas A. Selby, Jean M. Ihnat, Fredrick J. Post, Jay J. Messer
Reports
Artificial streams, soil perfusion columns, and potted plants were exposed to 20 ug Cd/l in the presence and absence of unretorted oil shale leachate. High cadmium accumulations occurred in the stream biota, but did not measurably affect community structure or function. The presence of oil shale leachate had no effect on bioaccumulation or ecosystem structure or function. Nitrification in soil columns was enhanced by the presence of the organic fraction of oil shale leachate, but this effect was not observed when cadmium was present. Crop accumulation of cadmium was somewhat higher in alfalfa and radishes irrigated with leachate, but did …
Alteration Of Availability Of Heavy Metals To Aquatic Microflora By Complexation With Organics Associated With Oil Shale Development, Bruce S. Mok, Jay J. Messer
Alteration Of Availability Of Heavy Metals To Aquatic Microflora By Complexation With Organics Associated With Oil Shale Development, Bruce S. Mok, Jay J. Messer
Reports
Leachates from both raw (unretorted) and Paraho retorted oil shale show the ability to bind copper, and perhaps cadmium, strongly enough to mitigate the inhibitory effects of these metals on the growth of the test algal,
Polycyclic Aromatic Hydrocarbons: Are They A Problem In Processed Oil Shales?, David L. Maase, V. Dean Adams
Polycyclic Aromatic Hydrocarbons: Are They A Problem In Processed Oil Shales?, David L. Maase, V. Dean Adams
Reports
Organic residues from processed oil shales were characterisized with specific attention to polycyclic aromatic hydrocarbons (PAH). Oil shale development in the White River Basin (Utah and Colorado) was projected and hydrological and geological parameters pertinent to estimations of polycyclic aromatic hydrocarbons (PAH) flux were focused. Oil shale samples from the Union B, Paraho, and Tosco II processes were extracted by using organic solvents in a soxhlet apparatus and by mixing shale samples with water (characterization in
Evaluation Of The Potential For Groundwater Transport Of Mutagenic Compounds Released By Spent Oil Shale, Robert E. Hinchee, V. Dean Adams, Jeffrey G. Curtis, Alberta J. Seierstad
Evaluation Of The Potential For Groundwater Transport Of Mutagenic Compounds Released By Spent Oil Shale, Robert E. Hinchee, V. Dean Adams, Jeffrey G. Curtis, Alberta J. Seierstad
Reports
The major focus of this study was on the potential mutagenicity of aqueous leachates from spent oil shale. Additional mutagenicity testing was also done on raw shale and coal. The Ames salmonella microsomal bioassay was used to test for chemical mutagenicity. Spent oil sahles from the Paraho and TOSCO II processes, a raw shale from Anvil Points, and a composite coal sample from the Wasatch plateau were extracted with water and organic solvents. Only organic solvent extraction of the TOSCO spent shale resulted in a mutagenic response. The lack of mutgenic reponse to organic extracts of Paraho spent shale was …
Eutrophication Assessment Of Mt. Dell Reservoir, Richard A. Hanson, V. Dean Adams, Vincent A. Lamarra, Kyle R. Cook, Dennis B. George
Eutrophication Assessment Of Mt. Dell Reservoir, Richard A. Hanson, V. Dean Adams, Vincent A. Lamarra, Kyle R. Cook, Dennis B. George
Reports
The degree and possible causes of eutrophication in Mt. Dell Reservoir, a small water supply reservoir in Parleys Canyon above Salt Lake City, were examined with a number of limnological studes. These studies described external (incoming stream flow) and internal (sediment) nutrient sources, general limnology, nutrient limitations, and trophic state. A monthly program of sampling at selected stream sites determined taht one area of mixed agricultural and undistrubed rangeland contributed significant amounts of total soluble inorganic nitrogen. Sediment phosphorus uptake and release rates were determined with aquatic three-phase microcosms. The results indicated that sediment phosphorus mass loadings were small (less …
Adapting Appropriation Water Law To Accommodate Equitable Consideration Of Instream Flow Uses, Jay M. Bagley, Dean T. Larson, Lee Kapaloski
Adapting Appropriation Water Law To Accommodate Equitable Consideration Of Instream Flow Uses, Jay M. Bagley, Dean T. Larson, Lee Kapaloski
Reports
The increasing public interest in naturally flowing streams has fostered efforts to obtain their protection under existing state water laws. In this study, the water laws of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming were examined and compared 1) with each other, and 2) against a set of aleitn criteria, to assess shortcomings in accommodating instream flow protections. It was determined that the appropriation system has the essential features of and ambodies legal principles that should allow the accommodation of instream flow values but, at this time, purchase of existing rights or the exercise of governmental reservation/withdrawal/appropriation …
Aquatic Resources Management Of The Colorado River Ecosystem, V. Dean Adams, Vincent A. Lamarra
Aquatic Resources Management Of The Colorado River Ecosystem, V. Dean Adams, Vincent A. Lamarra
Reports
The Colorado River system has often been referred to as "the most regulated river system in the world." The Colorado River Basin serves millions of people through agricultural, energy, municipal and industrial uses, fish and wildlife activities, and recreation. The symposium was conceived and organized to allow researchers, private industry, consultants, water users, regulatory agencies, and concerned citizens the opportunity to express needs, desires, and concerns about the vast resources of the Colorado River. We found that there were a diverse number of problems confronting the individuals who are involved in the management of this important ecosystem. A variety of …
Reconnaissance Of Sediment-Phosphorus Relationships In Upper Flaming Gorge Reservoir, Jay J. Messer, Jean M. Ihnat, Bruce Mok, David Wegner
Reconnaissance Of Sediment-Phosphorus Relationships In Upper Flaming Gorge Reservoir, Jay J. Messer, Jean M. Ihnat, Bruce Mok, David Wegner
Reports
Executive Summary: A reconnaissance-level study was conducted in Flaming Gorge Reservoir, Wyoming, during the late summer of 1982 in order to determine the possible importance of the sediment sin exacerbating the blue-green algal blooms that occur in summer in the upper reservoir. Sediments can affect phytoplankton dynamics in reservoirs on an annual basis by delyaing the availability of particulate P associated with spring runoff until late summery, when the warm water temperatures and the light climate favor the growth of blue-green algae. Over the longer term, however, sediments that historically have served as a trap for part of the annual …
Index Construction For Multiple Objective Analysis Of Land And Water Use In A High Mountain Watershed, L. Douglas James, Dean T. Larson, Mac Mckee, Jay J. Messer, Thomas M. Twedt, Randy Sperger, Barbara D. Campion, Frank J. Nemanich, Donald B. Porcella, Herbert H. Fullerton
Index Construction For Multiple Objective Analysis Of Land And Water Use In A High Mountain Watershed, L. Douglas James, Dean T. Larson, Mac Mckee, Jay J. Messer, Thomas M. Twedt, Randy Sperger, Barbara D. Campion, Frank J. Nemanich, Donald B. Porcella, Herbert H. Fullerton
Reports
Comprehensive planning is an elusive ideal. The practical planner must sort the relevant information from the vast amounts of data that modern technology can collect. The objective of this study was to use the Upper Blackfoot watershed in the mountains of Southeastern Idaho as an arena for developing methods for construction, refinement, and application of indices needed to design land and water management schemes, compare alternatives, and influence the public in their uses of the area. A total of 21 uses were examined on 242 land units of a 160 square-mile area ranging in elevation from 6300 to 9000 feet …
Bioassays- Procedures And Results, A. F. Maciorowski, L. W. Little, L. F. Raynor, Ronald C. Sims, J. L. Sims
Bioassays- Procedures And Results, A. F. Maciorowski, L. W. Little, L. F. Raynor, Ronald C. Sims, J. L. Sims
Biological Engineering Faculty Publications
Bioassay procedures to describe, evaluate, and predict the potential hazard of toxic materials to organisms and ecosystems, and the health-related aspects of polluted waters continue to receive widespread attention. Symposium proceedings and books pertinent to toxic substances management and test procedures have appeared, as have several literature reviews pertinent to specific pollutants. The proceedings of the fifth annual ASTM symposium on aquatic toxicology presented a collection of papers directed to research needs in aquatic toxicology and hazard assessment, new concepts in aquatic toxicology, biological availability and sediment toxicity, and hazard assessment and water quality criteria.1 A state-of-the-art overview pertinent …
Defensive Adaptations And Natural Enemies Of A Case-Bearing Beetle, Exema Canadensis (Coleoptera: Chrysomelidae), R. B. Root, Frank J. Messina
Defensive Adaptations And Natural Enemies Of A Case-Bearing Beetle, Exema Canadensis (Coleoptera: Chrysomelidae), R. B. Root, Frank J. Messina
Biology Faculty Publications
The larval habit of constructing and carrying a portable case has evolved many times in the Holometabola. It is a widespread trait of the Trichoptera and Lepidoptera (e.g. the Coleophoridae and Psychidae). Among the Coleoptera, casebearing is found in four related subfamilies of the Chrysomelidae, the so-called camptosomates: Clytrinae, Cryptocephalinae, Chlamisinae, and Lamprosomatinae (B6ving and Craighead 1931). The larval case of many insects is thought to function primarily in defense by providing armor or camouflage (Otto and Svensson 1980). Here we describe the uses of the case and other defenses in a chlamisine beetle, Exerna canadensis Pierce, and speculate briefly …
Potential Use Of Arkansas River Water For Irrigation In The Plum Bayou Watershed, Richard C. Peralta, Paul W. Dutram
Potential Use Of Arkansas River Water For Irrigation In The Plum Bayou Watershed, Richard C. Peralta, Paul W. Dutram
Civil and Environmental Engineering Faculty Publications
No abstract provided.
Utah Science Vol. 43 No. 4, Winter 1982
Utah Science Vol. 43 No. 4, Winter 1982
Utah Science
87 LUNG DISEASE MORTALITY IN UTAH MINERS (1959-1978) S. H. Kan and J. E. Brockert Miners have long suffered from diseases associated with their occupation. Data are examined relative to disease occurrence and resultant death rates.
90 IMPROVING BLACKBRUSH RANGES R. D. Provenza, J. E. Bowns, J. C. Malechek, P. J. Urness, and J. E. Butcher Blackbrush may be small in size, but it has king-size, tough spines. Using goats and controlled grazing, researchers are finding ways to optimize livestock use of this shrub. The results of four years research are reported here.
96 IMPACT OF TRADE LIBERALIZATION ON UTAH …
Primary Nectar Robbing In Mertensia Oblongifolia, A Case Study, Judith Visty
Primary Nectar Robbing In Mertensia Oblongifolia, A Case Study, Judith Visty
Biology
The primary nectar robbing of Mertensia oblongifolia (Nutt.) G. Don, a long-tubed bee-pollinated borage was investigated. The primary robbers, short-tongued Bombus occidentalis Cresson queens, removed nectar through a hole made in the corolla. These robber bumble bees were never observed to act as pollinators. The long-tongued solitary bee pollinators of M. oblongifolia concentrated their visits (>80%) during the hours 0900-1400 (MST). Pollinators did not seem to discriminate in visits between robbed and non-robbed flowers. Robber visits were more widely distributed from 0730 to 1500 (MST). During the part of the season when pollinators were most active their level of …
Effects Of Cyclic Nucleotide Metabolism And Light On The Control Of The Oscillations Of The Pineal Enzyme, N-Acetyltransferase, Annemarie B. Hamilton
Effects Of Cyclic Nucleotide Metabolism And Light On The Control Of The Oscillations Of The Pineal Enzyme, N-Acetyltransferase, Annemarie B. Hamilton
Biology
The purpose of this study was to examine the effects of light on the oscillations of the pineal enzyme, N-acetyltransferase through possible alterations in cyclic nucleotide metabolism. The levels of the cyclic nucleotides, cAMP and cGMP were measured in the chick pineal along with measurement of N-acetyltransferase activity in vivo and in vitro under cycling light (12 hours light: 12 hours dark) and under constant illumination. Activities of cAMP and cGMP phosphodiesterases and adenyl and guanyl cyclases were also measured under the same environmental conditions as those for the cyclic nucleotides, both in vivo and in vitro. Cyclic nucleotide levels …
Molt Schedules Of The Mountain Chickadee (Parus Gambeli) And The Black-Capped Chickadee (Parus Atricapillus), Antoinette Louise Pepin
Molt Schedules Of The Mountain Chickadee (Parus Gambeli) And The Black-Capped Chickadee (Parus Atricapillus), Antoinette Louise Pepin
Biology
Postnuptial wing molt was studied for Mountain Chickadees (Parus gambeli) and Black-capped Chickadees (Parus atricapillus) living in the Wasatch Mountains of northern Utah. The pattern of postnuptial wing molt was typical of many adult passerines. Three factors which might affect the timing and rate of molt were analyzed for these chickadees: sex, elevation and year. Molt for male chickadees was slower than for female chickadees. Male Mountain Chickadees began molt before female Mountain Chickadees. Mountain Chickadees live at higher elevations, where the frost-free season is shorter. Molt and winter territory establishment may overlap in the annual time budget of Mountain …
Studies Of Selected Predators Of Black Grass Bugs (Labops Hesperius Uhler And Irbisia Brachycera Uhler) On Ranges Of Utah, Jaime Eduardo Araya
Studies Of Selected Predators Of Black Grass Bugs (Labops Hesperius Uhler And Irbisia Brachycera Uhler) On Ranges Of Utah, Jaime Eduardo Araya
Biology
The activity of selected arthropod predators on both immature and adult black grass bugs, Labops hesperius Uhler and Irbisia brachycera Uhler, in infested Utah ranges was investigated. Adult Nabis alternatus was found to the most important predator of black grass bugs, especially in early spring, when nabids were the most abundant predaceous species. Immature nabids consumed the bugs but because of their smaller size they preyed mostly on leafhoppers, smaller plant bug nymphs and other immature nabids. A shortwinged species of Nabis (probably N. vanduzeei) showed good potential as a predator of adult Labops and Irbisia in laboratory feeding tests. …
Locomotion Of Rock Squirrels (Spermophilus Variegatus), Awadh Al-Johny
Locomotion Of Rock Squirrels (Spermophilus Variegatus), Awadh Al-Johny
Biology
Locomotion and climbing ability of rock squirrels (Spermophilus variegatus) were studied in an outdoor enclosure from June 15 to July 30, 1981, and in an indoor enclosure from October 1981 to June 1982. Dowels and tree branches of different diameters were used to test the animals' climbing ability and movements. Uinta ground squirrels (Spermophilus armatus) and red squirrels (Tamiasciurus hudsonicus) were used for comparison. Animals were filmed with a 16 mm camera and a videotape earners. Films were analyzed using a slow motion projector, and drawings were made directly from the films. Speed in m/s and kph and maximum horizontal …
The Biology And Ecology Of Eumegachile (Sayapis) Pugnata (Say) (Hymenoptera: Megachilidae), A Pollinator Of Commercial Sunflower, Donald R. Frohlich
The Biology And Ecology Of Eumegachile (Sayapis) Pugnata (Say) (Hymenoptera: Megachilidae), A Pollinator Of Commercial Sunflower, Donald R. Frohlich
Biology
Eumegachile (Sayapis) pugnata (Say) was studied in a greenhouse and in the field to elucidate its natural history and evaluate its potential as a pollinator of commercial sunflower. Cell building, provisioning, ovipositioning, and development are described. Mortality factors, emergence sequences, sizes, and sex ratios were similar to those reported in other studies. Unlike social bees E. pugnata foraged in such a way that pollen collection and not energy (nectar) acquisition was maximized. Characteristics that contribute to its manageability as a pollinator include the fact that it nests successfully in man made devices that can be moved from field to field …
Avian Resource Partitioning Along A Montane Sere, Kimberly Gray Smith
Avian Resource Partitioning Along A Montane Sere, Kimberly Gray Smith
Biology
Avian vegetation-use and foraging behavior were studied along a spruce-fir sere in the Bear River Mountains of northern Utah and southern Idaho from 1976 to 1978 on four 10 ha plots--one each in meadow, aspen, fir and spruce. A total of 71 species were encountered, of which 43 bred in at least one of three breeding seasons. Avian vegetation-use was quantified on the 3 forested plots by sampling a total of 197 (0.05ha) plots around singing male birds of 15 species. Also, 75 random plots (25 in each seral stage) were sampled to characterize the available vegetation. Principal component analysis …
Studies On Rotavirus Growth In Cell Culture And Various Aspects Of Replication, Scott M. Clark
Studies On Rotavirus Growth In Cell Culture And Various Aspects Of Replication, Scott M. Clark
Biology
The effect of trypsin on the infectivity and cultivation of rotaviruses has been studied. It was found that trypsin increases the infectivity of bovine, simian and porcine rotaviruses from 10 to 400-fold and that the enzyme increases the yield of bovine rotavirus in cell culture up to 1000-fold. Studies on the mechanism of trypsin enhancement of rotaviral infectivity indicate that the enzyme facilitates the uncoating of parental virus in the infected cell. Studies on the involvement of two particle types in bovine rotavirus replication indicate that the yield of light (L) infectious virions and dense (D) non-infectious particles in various …
Factors Determining The Abundance And Distribution Of Rodents In A Shrub-Steppe Ecosystem: The Role Of Shrubs, Robert R. Parmenter
Factors Determining The Abundance And Distribution Of Rodents In A Shrub-Steppe Ecosystem: The Role Of Shrubs, Robert R. Parmenter
Biology
This study addressed the relative importances of shrub "resources" on a rodent community in a sagebrush dominated shrub-steppe ecosystem in southwestern Wyoming. Direct effects of shrubs (i.e., providing rodents with "food and cover") were assessed by removing shrubs from a 1.25 ha study plot and monitoring both rodent populations and their food resources. Shrub-related "food and cover" was found to be unimportant to deermice (Peromyscus maniculatus), Great Basin pocket mice (Perognathus parvus), northern grasshopper mice (Onychomys leucogaster) and Uinta ground squirrels (Speromphilus armatus), as shrub removal caused no significant changes in population sizes, sex ratios or age structure. Least chipmunks …