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Dataobtained from the USU incoherent backscatter lidar at Logan Utahduring the interval 1994 through 1998 has been analyzed interms of the climatology of stratospheric and lower mesospheric meandensity and density variance (delta) (rho) /(rho) )2 vs. altitude.The total database consists of over 322 nights of cloud-freedata over the altitude range, 40 to 90 km. Weselected a subset of 142 days (886 hours) of thehighest signal to noise ratio data for the analysis. Thetemporal and spatial resolutions were 2 minutes and 112.5 metersrespectively. We compared the mean density profiles, normalized to MSISe90on a monthly and seasonal basis to MSISe90. The meandensity profiles compared well with the MSISe90 model with thefollowing...
Bats utilizing water sources within plateau forests were surveyed at 24 sites in southern and central Utah. Fourteen taxa were captured, with eight of these formerly listed by the U.S. Fish and Wildlife Service as Category 2 species. The first documented capture of Euderma maculatum from the Manti-LaSal Mountains is noted. Published in Proceedings of the Third Biennial Conference of Research on the Colorado Plateau, in 1996.
Development of criteria and indicators that can be used to evaluate nutrient cycling among plants, animals, and the soil is essential for evaluating rangeland health and sustainability, as well as for developing proper rangeland management practices. The distribution of nutrients in space and time has been identified as a useful criterion for evaluating the integrity of rangeland nutrient cycles and energy flow in rangelands. Spatial distributions of soil organic carbon (C) and organic and mineral nitrogen (N) were measured in both mid- and late-seral stages of a sagebrush-grass association. Vegetation cover differed between the two seral stages, with grass cover significantly higher (15 versus 3 percent), and bare...
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Aspen exhibits a variety of ecological roles. In southern Colorado, the 1880 landscape mosaic contained a range of stand ages, of which half were >70 years old and half were younger. Pure aspen stands in southern Colorado are widespread and may result from previous short fire intervals that eliminated local conifer seed sources. Aspen regeneration in northern Yellowstone Park is controlled by ungulate browsing pressure and fire, so it has been limited since 1920. However, an episode of aspen seedling establishment occurred after the 1988 fires. We urgently need additional detailed, local case studies of aspen ecology to inform management decisions. Published in Sustaining Aspen in Western Landscapes: Symposium Proceedings,...
Abiotic and non-chemical factors may limit the ability of a stream to respond to improvements in traditional water quality parameters because physical habitat and sediment characteristics may also limit the populations of aquatic animals. A reach of the Upper Animas River in southwestern Colorado is analyzed to show possible limits caused by physical habitat and sediment. Habitat for trout in the Animas River near Howardsville may be limited by high streamflows (because of high velocities) and by winter conditions (by velocities too high for winter habitat needs and low depths). The characteristics of the substrate (bed material) may offset the impacts of high velocities in the spring and the depths and velocities...
Utah'shistory over the past several hundred years and the availabilityof water correlate closely and help to explain its past.Water influenced the way of life of the Native Americansand when the Mormon pioneers arrived in the Salt LakeValley in July 1847 the availability of water would determinetheir method of colonizing the region. Out of necessity, pioneersadopted the concept of the prior appropriation doctrine, which fundamentalprinciple is first in time, first in right. Much ofthe early administration and development of water in Utah wasdone under cooperative irrigation systems. Initially the State Engineer hadlimited power and authority to only measure stream flow, approveplans for dams and assist in resolving...
Categories: Publication; Types: Citation, Conference Citation; Tags: ASCE
Sagebrush shrublands of southern California and the Great Basin are both undergoing massive vegetation-type conversion to exotic annual grasslands dominated by brome species. In southern California the main players are California sagebrush and red brome, while the Intermountain Region has big sagebrush and cheatgrass. Exotic annuals tend to be more dominant in soils with moderate to high levels of soil P and N. The type conversion of California sagebrush shrublands has been occurring during the last 25 to 30 years, compared to the last 100 years in the Great Basin. One reason for this might be the recent increase in anthropogenic N deposition caused by automobile emissions, up to 30 kg N per ha year. Field fertilization...
A number of studies have shown that dust delivers essential nutrients that sustain terrestrial productivity over millennia. Dust, however, contains a range of elements ranging from base cations, N and P, to heavy metals. Some of these elements will stimulate primary productivity over the time scale of soil development while others, such as metals, could inhibit biological activity. As dust accumulates, it also influences water flux and availability by altering soil texture. We are examining the ecological impacts of dust accumulation in Canyonlands National Park in Utah. Using magnetic susceptibility as a proxy for far-traveled dust, we have established transects in sandy surficial deposits (50-90% sand) in which...
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From 1988-1991, I studied desert rodent communities of the Canyon Country Province, Colorado Plateau. Study areas were located in Capitol Reef National Park, Utah and represented grassland, shrubland, and woodland habitats. I examined species richness, guild structure, body size, and microhabitat use, testing predictions based on patterns documented in other North American desert rodent faunas. Rodent assemblages were relatively simple with respect to species richness and number of taxonomic/foraging guilds. Among coexisting species, only the numerically dominant omnivores exhibited non-random body size. Co-occurences of species representing three taxonomic-foraging guilds were significantly different from expected...
Determination of the pre-mining geochemical baseline in bed sediments and the paleoecology in a watershed impacted by historical mining activity is of utmost importance in establishing watershed restoration goals. We have approached this problem in the Animas River watershed using geomorphologic mapping methods to identify old pre-mining sediments. A systematic evaluation of possible sites resulted in collection of a large number of samples of pre-mining sediments, overbank sediments, and fluvial tailings deposits from more than 50 sites throughout the watershed. Chemical analysis of individual stratigraphic layers has resulted in a chemical stratigraphy that can be tied to the historical record through geochronological...
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From January 1997 through October 1998, research was conducted at Canyonlands National Park to investigate soil traits responsible for distinct spatial patterns of cheatgrass (Bromus tectorum) occurrence. Field experiments were conducted at sites representing a broad range of soil conditions and cheatgrass abundances. Standard physicochemical soil measures in combination with innovative ion-exchange resin capsules and bags were used to describe spatial and seasonal soil variations. Cheatgrass performance varied along a complex, multivariate soil gradient, with the strongest cheatgrass-soil relationship occurring during winter. Biogeochemical principles, soil measures, growth rates, and leaf-tissue analyses support...
Objective 3: Use historical fish data (1963-2009) to determine whether variation in recruitment of several fish species (alewife, bloater, rainbow smelt, lake whitefish, and yellow perch) can be explained by climate-related factors such as water temperature, water level, primary production, or ice cover, in addition to other presumed important biotic factors. Paris Collingsworth (University of Michigan, post-doctoral scientist) and David Bunnell (USGS PI) have focused on predicting recruitment of alewife, bloater, and rainbow smelt in lakes Michigan and Huron. We used traditional Ricker analyses (with external explanatory variables) for alewife and rainbow smelt, but had to use a Bayesian Dynamic Linear Model to...
The role of cryptobiotic soil crusts in the functioning of semiarid and arid ecosystems is discussed. These roles include microstructuring of soils in cold-desert ecosystems, influencing soil nutrient levels, and influencing the nutrient status, germination, and establishment of vascular plants in crusted areas when compared to uncrusted areas. For these reasons, re-establishment of these crusts should be an important part of reclamation efforts. Natural recovery rates and the effectiveness of inoculation efforts are discussed. Published in Symposium on Ecology, Management, and Restoration of Intermountain Annual Rangelands, on pages 179 - 185, in 1994.
TheCentral Utah Water Conservancy District (District) is a political subdivisionof the State of Utah originally charged with managing andoperating the Central Utah Project, a federally funded water project.The District covers 10 counties of Utah and provides culinaryand secondary water to a wide range of communities andwater districts within these counties. They are primarily a waterwholesaler and provide water to communities and other water districts.They operate several dams, reservoirs, canals, pipelines, tunnels, and watertreatment plants. In 2005, the District opted to purchase about42,000 acre-feet of groundwater rights, 23 existing wells, pipelines, apump station and other associated assets made available...
Categories: Publication; Types: Citation, Conference Citation; Tags: ASCE
TheArid West is the fastest growing region of the country.Expanding development in this harsh environment brings new stormwater managementchallenges. Bioretention present unique engineering and ecological challenges different thanmore mesic regions of the country. To address these challenges,two bioretention cells are being constructed in Salt Lake Cityto test performance in an arid climate. Factors driving plantselection and design are expected delivery of annual precipitation aswell as physiological traits of native plant species. First, expectedprecipitation amounts and pattern of delivery are reviewed for SaltLake City. Second, physiological benefits and restraints of selected uplandspecies from the area are...
Biological soil crusts (BSC) are a dominant feature in arid and semi-arid ecosystems. BSC stabilize soils, contribute nitrogen and carbon, enhance vascular plant nutrition, and influence local hydrologic cycles. However, these ecological roles are determined by the species composition, morphology, and physiological functioning of the BSC. These factors, in turn, can be strongly affected by land use, invasive plants, and climate change. Soil surface disturbance and/or dominance by invasive plants both result in loss of lichens and mosses, leaving cyanobacteria dominating the soil surface. This loss reduces soil stability, carbon and nitrogen contributions, surface temperatures, and soil water retention times. Climate...
Thehigh demand for water, the recent multiyear drought (1999–2007), andprojections of global warming have raised questions about the long-termsustainability of water supply in the southwestern United States. Inthis study, the potential effects of specific levels of atmosphericwarming on water-year streamflow in the Colorado River basin areevaluated using a water-balance model, and the results are analyzedwithin the context of a multi-century tree-ring reconstruction (1490–1998) ofstreamflow for the basin. The results indicate that if futurewarming occurs in the basin and is not accompanied byincreased precipitation, then the basin is likely to experience periodsof water supply shortages more severe than those...
In arid and semiarid lands throughout the world, the cover of vegetation is generally sparse or absent. Open spaces between the higher plants are not bare of autotrophic life but usually covered by a community of highly specialized organisms. This soil surface floral community consists of cyanobacteria, green algae, lichens, mosses, microfungi, and other bacteria. Cyanobacterial and microfungal filaments weave throughout the top few millimeters of soil, gluing loose soil particles together to form a biological crust. These crusts occur in all hot, cool, and cold arid and semiarid regions. They may constitute up to 70% of the living cover (Belnap 1994) and have only recently been recognized as having a major influence...
Native and invasive trout distributions in the Upper Columbia Basin under climate change: influence of flow regime, temperature and biotic interaction, credited to Hamlet, A F, published in 2010. Published in Idaho State University, Pocatello, ID. February 4, 2010, in 2010.
Woody plant encroachment is a widespread process of land cover change from grassland to shrubland which has the potential to impact faunal communities around the globe. This process may be driven by multiple factors including overgrazing, fire management, warmer temperatures, changes in nutrient deposition rates, and CO2 direct effects. Though recognized as a threat to human populations through its detrimental effects on rangeland quality and carrying capacity, little is known about the impact that woody plant encroachment may have on native mammals, especially predators. This study assesses the bottom-up effects of woody plant encroachment on an abundant, top predator in an area where shrubs have spread into a...
map background search result map search result map Aspen's ecological role in the West Components of Spatial and Temporal Soil Variation at Canyonlands National Park: Implications for P Dynamics and Cheatgrass (Bromus tectorum) Performance Desert Rodent Communities of the Canyon Country Province, Colorado Plateau Components of Spatial and Temporal Soil Variation at Canyonlands National Park: Implications for P Dynamics and Cheatgrass (Bromus tectorum) Performance Desert Rodent Communities of the Canyon Country Province, Colorado Plateau Aspen's ecological role in the West