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The use of airborne hyperspectral remote sensing imagery for automated mapping of submerged aquatic vegetation (SAV) in the tidal Potomac River was investigated for near to real-time resource assessment and monitoring. Airborne hyperspectral imagery and field spectrometer measurements were obtained in October of 2000. A spectral library database containing selected ground-based and airborne sensor spectra was developed for use in image processing. The spectral library is used to automate the processing of hyperspectral imagery for potential real-time material identification and mapping. Field based spectra were compared to the airborne imagery using the database to identify and map two species of SAV ( Myriophyllum...
Categories: Publication; Types: Citation
Mercury contamination of aquatic ecosystems is an issue of national concern, affecting both wildlife and human health. Detailed information on mercury cycling and food-web bioaccumulation in stream settings and the factors that control these processes is currently limited. In response, the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) conducted detailed studies from 2002 to 2006 on various media to enhance process-level understanding of mercury contamination, biogeochemical cycling, and trophic transfer. Eight streams were sampled for this study: two streams in Oregon, and three streams each in Wisconsin and Florida. Streambed-sediment and pore-water samples were collected between...
Categories: Publication; Types: Citation
In a survey study conducted to obtain base-line data, eleven extensive float trips were made down the Colorado River in the period from September 1970 through mid-June 1976. Samples of fish, mammals, plants and herpetofauna were collected; species collected are listed. In addition, terrestrial surveys were made at various land sites in the region. Major results of this survey were the lack of success in obtaining a speciman of the humpback sucker, xyrauchen texanus, and the discovery of the relative scarcity of chubs of the genus Gila. Both of these outcomes have been tied to the low water temperatures caused by releases from the Grand Canyon Dam, as well as to the barrier that the dam presents to upstream movement...
SLAMM Modeling of Yaquina Estuary, Central Oregon Coast, credited to Loiselle, R., published in 2010. Published in Oregon Climate Change Research Institute’s (OCCRI) PNW Climate Science Conference, June 15-16, in 2010.
Environmental Chemistry of Selenium: Written as a complement to the definitive work, Selenium in the Environment (Marcel Dekker, Inc.), this timely resource presents basic and the most recent applied research developments in selenium remediation - emphasizing field investigations as well as covering topics from analytical methods and modeling to regulatory aspects from federal and state perspectives. Published in Environmental Chemistry of Selenium, on pages 297 - 313, in 1998.
Black-footed ferrets (Mustela nigripes) excavate subsoil from black-tailed prairie dog (Cynomys ludovicianus) burrows and deposit it in unique piles. Black-tailed prairie dogs tend to fill in or "plug" burrows visited or occupied by ferrets (Hillman 1968, Henderson et al. 1969, Fortenbery 1972). In this paper, we describe the configuration, rate of production, persistence, and seasonality of ferret diggings and rate of burrow plugging by prairie dogs within white-tailed prairie dog (C. leucurus) colonies. Published in Journal of Wildlife Management, volume 48, issue 4, on pages 1441 - 1444, in 1984.
The Crystal Geyser Dinosaur Quarry, near Green River, Utah, is located at the base of the Lower Cretaceous (Barremian) Yellow Cat Member of the Cedar Mountain Formation. The quarry preserves a nearly monospecific accumulation of a new basal therizinosauroid, Falcarius utahensis. We used field descriptions and petrographic analysis to determine the depositional environment and development of the quarry strata. Results of these analyses suggest that the quarry represents multiple episodes of bone accumulation buried by spring and overbank flood deposits. Evidence for these previously undescribed spring deposits includes calcite macroscopic structures within the quarry strata—such as pisolites and travertine fragments—and...
Categories: Publication; Types: Citation, Journal Citation; Tags: PALAIOS
A selected survey of Rocky Mountain/Great Plains riparian research with emphasis on livestock grazing impacts and management is presented. A multiuniversity plan for studying interactions between livestock grazing and riparian resources in the region is presented. The power of an integrated, regionwide approach is compared with that of one involving the conduct of numerous independent, site-specific studies. An analogy is made to California, considering the State as a region. The need for support of long-term riparian research by traditional academic funding sources is also stressed. Published in California Riparian Systems: Ecology, Conservation, and Productive Management, on pages 413 - 423, in 1984.
The pollen of three Ephedra taxa, Ephedra torreyana, E. trifurca and E. funerealeft right double arrowE. torreyana, showed a marked pollen dimorphism when examined using scanning electron microscopy. Typical pollen grains in all of these taxa have straight ridges, but the variant forms exhibit a highly folded ectexine. In addition, previously used characters such as the presence or absence of bifurcating valley structure do not appear to be uniform, even within a single microsporangium, suggesting that their value to taxonomic study should be reassessed. Published in Review of Palaeobotany and Palynology, volume 124, issue 3-4, on pages 325 - 334, in 2003.
Intensive non-native removal efforts from PNM Weir to Hogback Diversion (RM 166.6 – 159.0) continued for the third consecutive year in 2003. These efforts initially began to assess efficacy of mechanical removal as an efficient method of decreasing the distribution and abundance of non-native fishes, with emphasis on channel catfish and common carp. These efforts have been recognized as a Recovery Action by the San Juan River Recovery Implementation Program (SJRIP).
Macroscale hydrologic modeling of ecologically relevant flow metrics in small streams, credited to Hamlet, A F, published in 2010. Published in USFS Region 6 annual meeting, Vancouver, WA., in 2010.
Our studies of the association between the lesser earless lizard (Holbrookia maculata) and Gunnison's prairie dogs (Cynomys gunnisoni) revealed: (1) the lesser earless lizard was more abundant on prairie dog colonies than off, (2) lesser earless lizard abundance was positively correlated with prairie dog burrow abundance; (3) lesser carless lizards responded positively to artificial burrows created on noncolonized areas; and (4) lesser earless lizards used prairie dog burrows as refuges from predators; however, the relative use of burrows was greatest at high and low temperature extremes. Although prairie dogs alter habitat in many ways, our study suggests that burrows are an important mechanism involved in the...
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The synthesis of glycosaminoglycans (GAG) in a freshwater mussel was studied in organ culture using labeled precursors. The major GAGs synthesized were determined and characterized by chemical and enzymatic methods. They were shown to be heparin and an unusual type of heparan sulfate. Gills produced about 50% of each polymer; mantles synthesized little heparin and mostly the heparan-sulfate-like compound, which is similar to a GAG isolated previously from lobsters. No significant amounts of chondroitin sulfates were present. Histological data showed that the sulfate-labeled GAGs were present mainly in exterior pericellular and basement membrane locations of gills and mantle. That is, they would be in contact with...
The length of gestation is the number of days between fertilization and parturition, and the length of lactation is the number of days between parturition and weaning. Determination of these lengths is difficult for ground-dwelling squirrels such as prairie dogs, marmots, and ground squirrels that usually copulate, give birth, and nurse offspring underground. For Gunnison's prairie dogs (Cynomys gunnisoni), the mean +1 SD length of gestation is 29.3 ? 0.53 days (n = 124). The approximate length of lactation, estimated from the mean +1 SD duration between parturition and the first emergence of juveniles from the natal burrow, is 38.6 ? 2.08 days (n = 112). Published in Journal of Mammalogy, volume 78, issue 1, on...
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Theoverthrust belt of western North America extends from British Columbiato southern Nevada. Large anticlines lie on thrust sheets alongthe length of this overthrust trend. Many oil and gasfields have been discovered on these structures in Canada, butsignificant hydrocarbon production in the United States has been primarilylimited to a productive salient in southwestern Wyoming and northeasternUtah (Figure 1). On 23 December 2003, Wolverine Gas andOil-Kings Meadow Ranches well 17-1 drilled into a 487-ft oilcolumn in the Navajo Sandstone in Sevier County, Utah. Thisnew significant oil reservoir is 146 miles southwest of thenearest thrust belt production at Pineview Field in Summit County,Utah. The discovery of what...
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Sage-grouse (Centrocercus spp.) were abundant in all of Utah's 29 counties at the time of European settlement wherever sagebrush (Artemisia spp.) occurred. Greater Sage-Grouse (G. urophasianus) inhabited areas north and west of the Colorado River, and Gunnison Sage-Grouse (G. minimus) occupied suitable habitat south and east of the Colorado River. The largest Greater Sage-Grouse populations in Utah are currently restricted to suitable habitats in Box Elder, Garfield, Rich, Uintah, and Wayne Counties. A remnant breeding population of Gunnison Sage-Grouse occurs in eastern San Juan County. We stratified Greater Sage-Grouse populations (1971-2000) by counties where the 1996 to 2000 moving average for estimated spring...
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The focus of this report is the endangered and threatened fishes of the Upper Colorado River system, but a full appreciation would not be possible without an adequate knowledge of the ecosystems in which they live. The six major sections of the report are: abiotic components, biological components, species description, river basin descriptions, major factors inducing environmental change, and urgent needs and recommended research priorities in regard to the upper Colorado River System. (Deal-EIS)
Categories: Publication; Types: Citation, Thesis Citation
An accounting procedure is developed which determines a flow regime that is capable of transporting an amount of bedload sediment necessary to ensure channel stability downstream. The method allows for sediment buildup in the channel within geomorphic threshold limits during low flow periods. During periods of high runoff, enough water is bypassed to transport the stored sediment. The procedure utilizes only those flows of sufficient magnitude to maintain channel stability over the long run (25–50+ years). An example is presented which determines the volume of water and frequency of release for channel maintenance purposes downstream from a hypothetical water diversion project. Of some 1,200,000 acre feet generated...
As an estimate of species-level differences in the capacity to take up different forms of N, we measured plant uptake of 15N-NH4+, 15N-NO3- and 15N, [1]-13C glycine within a set of herbaceous species collected from three alpine community types. Plants grown from cuttings in the greenhouse showed similar growth responses to the three forms of N but varied in the capacity to take up NH4+, NO3- and glycine. Glycine uptake ranged from approximately 42% to greater than 100% of NH4+ uptake; however, four out of nine species showed significantly greater uptake of either NH4+ or NO3- than of glycine. Relative concentrations of exchangeable N at the sites of plant collection did not correspond with patterns of N uptake among...
map background search result map search result map Changes in the distribution and status of sage-grouse in Utah An evaluation of habitat conditions and species composition above, in, and below the Atomizer Falls Complex of the Little Colorado River Covenant Field: A major oil discovery in the Sevier thrust belt of central Utah Glycosaminoglycans in Anodonta californiensis, a freshwater mussel Covenant Field: A major oil discovery in the Sevier thrust belt of central Utah Glycosaminoglycans in Anodonta californiensis, a freshwater mussel An evaluation of habitat conditions and species composition above, in, and below the Atomizer Falls Complex of the Little Colorado River Changes in the distribution and status of sage-grouse in Utah