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A comparison of survey methods to evaluate macrophyte index of biotic integrity performance in Minnesota lakes
Bruce C. Vondracek, Justine D. Koch, Marcus W. Beck
2014, Ecological Indicators (36) 178-185
Aquatic macrophytes shape trophic web dynamics, provide food and refuge for macroinvertebrates and fish, and increase nutrient retention, sediment stabilization, and water clarity. Macrophytes are well-suited as indicators of ecological health because they are immobile, relatively easy to sample and identify, and respond to anthropogenic disturbance on an ecological time...
Winter feeding, growth and condition of brown trout Salmo trutta in a groundwater-dominated stream
William E. French, Bruce C. Vondracek, Leonard C. Ferrington Jr., Jacques C. Finlay, Douglas J. Dieterman
2014, Journal of Freshwater Ecology (29) 187-200
Winter can be a stressful period for stream-dwelling salmonid populations, often resulting in reduced growth and survival. Stream water temperatures have been identified as a primary mechanism driving reductions in fitness during winter. However, groundwater inputs can moderate water temperature and may reduce winter severity. Additionally, seasonal reductions in prey...
Self-confidence of anglers in identification of freshwater sport fish
C.J. Chizinski, D. R. Martin, Kevin L. Pope
2014, Fisheries Management and Ecology (21) 448-453
Although several studies have focused on how well anglers identify species using replicas and pictures, there has been no study assessing the confidence that can be placed in angler's ability to identify recreationally important fish. Understanding factors associated with low self-confidence will be useful in tailoring education programmes to improve...
Carcass analog provides marine subsidies for macroinvertebrates and juvenile Atlantic 8 salmon in temperate oligotrophic streams
Margaret Q. Guyette, Cynthia S. Loftin, Joseph D. Zydlewski, Richard Cunjak
2014, Freshwater Biology (59) 392-406
Anadromous fish populations entering freshwater ecosystems provide organic matter and marine-derived nutrients during spawning and subsequent mortalities of adults. Dams and other impediments to connectivity in rivers and streams have affected anadromous fish populations in many regions and prevented or reduced this influx of organic materials and...
A comparison of two gears for quantifying abundance of lotic-dwelling crayfish
Kristi Williams, Shannon K. Brewer, Mark R. Ellersieck
2014, Journal of Crustacean Biology (34) 54-60
Crayfish (saddlebacked crayfish, Orconectes medius) catch was compared using a kick seine applied two different ways with a 1-m2 quadrat sampler (with known efficiency and bias in riffles) from three small streams in the Missouri Ozarks. Triplicate samples (one of each technique) were taken from two creeks and one headwater...
A new species of freshwater eel-tailed catfish of the genus Tandanus (Teleostei: Plotosidae) from the Wet Tropics Region of Eastern Australia
Stuart A. Welsh, Dean R. Jerry, Damien Burrows
2014, Copeia (2014) 136-142
Tandanus tropicanus, new species, is described based on specimens from streams in the wet tropics region of northeast Queensland. Previously, two species were recognized in the genus Tandanus: T. tandanus of eastern Australia and T. bostocki of Western Australia. A combination of meristic and morphometric characters distinguishes the new species from all congeners. Further, taxonomic...
Using lead isotopes and trace element records from two contrasting Lake Tanganyika sediment cores to assess watershed – Lake exchange
Kingsley Odigie, A.D. Cohen, Peter W. Swarzenski, R Flegal
2014, Applied Geochemistry (51) 184-190
Lead isotopic and trace element records of two contrasting sediment cores were examined to reconstruct historic, industrial contaminant inputs to Lake Tanganyika, Africa. Observed fluxes of Co, Cu, Mn, Ni, Pb, and Zn in age-dated sediments collected from the lake varied both spatially and temporally over the past two to...
Potentiometric surface and water-level difference maps of selected confined aquifers in Southern Maryland and Maryland’s Eastern Shore, 1975-2013
Andrew W. Staley, David C. Andreasen, Stephen E. Curtin
2014, Open-File Report 14-02-02
Groundwater is the principal source of freshwater supply in most of Southern Maryland and Maryland’s Eastern Shore. It is also the source of freshwater supply used in the operation of the Calvert Cliffs, Chalk Point, and Morgantown power plants. Increased groundwater withdrawals over the last several decades have caused groundwater...
Northern Pintail
Robert G. Clark, Joseph P. Fleskes, Karla L. Guyn, David A. Haukos, Jane E. Austin, Michael R. Miller
2014, The Birds of North America
This medium-sized dabbling duck of slender, elegant lines and conservative plumage coloration is circumpolar in distribution and abundant in North America, with core nesting habitat in Alaska and the Prairie Pothole Region of southern Canada and the northern Great Plains. Breeders favor shallow wetlands interspersed throughout prairie grasslands or arctic...
Tracking changes in volcanic systems with seismic Interferometry
Matthew M. Haney, Alicia J. Hotovec-Ellis, Ninfa L. Bennington, Silvio De Angelis, Clifford Thurber
2014, Book chapter, Encyclopedia of Earthquake Engineering
The detection and evaluation of time-dependent changes at volcanoes form the foundation upon which successful volcano monitoring is built. Temporal changes at volcanoes occur over all time scales and may be obvious (e.g., earthquake swarms) or subtle (e.g., a slow, steady increase in the level of tremor). Some of the...
Statistical assessment on a combined analysis of GRYN-ROMN-UCBN upland vegetation vital signs
Kathryn M. Irvine, Thomas J. Rodhouse
2014, Natural Resource Report NPS/UCBN/NRR—2014/855
As of 2013, Rocky Mountain and Upper Columbia Basin Inventory and Monitoring Networks have multiple years of vegetation data and Greater Yellowstone Network has three years of vegetation data and monitoring is ongoing in all three networks. Our primary objective is to assess whether a combined analysis of these data...
Summary of preliminary step-trend analysis from the Interagency Whitebark Pine Long-termMonitoring Program—2004-2013
Kristin Legg, Erin Shanahan, Rob Daley, Kathryn M. Irvine
2014, Natural Resource Data Series NPS/GRYN/NRDS—2014/600
In mixed and dominant stands, whitebark pine (Pinus albicaulis) occurs in over two million acres within the six national forests and two national parks that comprise the Greater Yellowstone Ecosystem (GYE). Currently, whitebark pine, an ecologically important species, is impacted by multiple ecological disturbances; white pine blister rust (Cronartium ribicola),...
Fifty-fifth supplement to the American Ornithologists' Union Check-list of North American Birds
R. Terry Chesser, Richard C. Banks, Carla Cicero, Jon L. Dunn, Andrew W. Kratter, Irby J. Lovette, Adolfo G. Navarro-Siguenza, Pamela C. Rasmussen, J.V. Remsen Jr., James D. Rising, Douglas F. Stotz, Kevin Winker
2014, The Auk (131) CSi-CSxv
This is the 14th supplement since publication of the 7th edition of the Check-list of North American Birds (American Ornithologists' Union [AOU] 1998). It summarizes decisions made between May 15, 2013, and May 15, 2014, by the AOU's Committee on Classification and Nomenclature - North and Middle America. The Committee...
Development and characterization of 12 microsatellite markers for the Island Night Lizard (Xantusia riversiana), a threatened species endemic to the Channel Islands, California, USA
Ryan P. O’Donnell, Charles A. Drost, Karen E. Mock
2014, Conservation Genetics Resources (6) 699-700
The Island Night Lizard is a federally threatened species endemic to the Channel Islands of California. Twelve microsatellite loci were developed for use in this species and screened in 197 individuals from across San Nicolas Island, California. The number of alleles per locus ranged from 6 to 21. Observed heterozygosities...
The impact of climate and reservoirs on longitudinal riverine carbon fluxes from two major watersheds in the Central and Intermontane West
Sarah M. Stackpoole, Edward G. Stets, Robert G. Striegl
2014, Journal of Geophysical Research: Biogeosciences (119) 848-863
A nested sampling network on the Colorado (CR) and Missouri Rivers (MR) provided data to assess impacts of large-scale reservoir systems and climate on carbon export. The Load Estimator (LOADEST) model was used to estimate both dissolved inorganic and organic carbon (DIC and DOC) fluxes for a total of 22...
Studying seafloor bedforms using autonomous stationary imaging and profiling sonars
Ellyn T. Montgomery, Christopher R. Sherwood
2014, Conference Paper, OCEANS 2013: Proceedings of a meeting held 23-27 September 2013, San Diego, California, USA
The Sediment Transport Group at the U.S. Geological Survey, Woods Hole Coastal and Marine Science Center uses downward looking sonars deployed on seafloor tripods to assess and measure the formation and migration of bedforms. The sonars have been used in three resolution-testing experiments, and deployed autonomously to observe changes in...
Exchange of nitrogen and phosphorus between a shallow lagoon and coastal waters
Melanie Hayn, Robert W. Howarth, Neil K. Ganju, Peter Berg, Kenneth H. Foreman, Anne E. Giblin, Karen McGlathery
2014, Estuaries and Coasts (37) 63-73
West Falmouth Harbor, a shallow lagoon on Cape Cod, has experienced a threefold increase in nitrogen load since the mid- to late 1990s due to input from a groundwater plume contaminated by a municipal wastewater treatment plant. We measured the exchange of nitrogen and phosphorus between the harbor and the...
Molecular signature of organic nitrogen in septic-impacted groundwater
William A. Arnold, Krista Longnecker, Kevin D. Kroeger, Elizabeth B. Kujawinski
2014, Environmental Science: Processes and Impacts (16) 2400-2407
Dissolved inorganic and organic nitrogen levels are elevated in aquatic systems due to anthropogenic activities. Dissolved organic nitrogen (DON) arises from various sources, and its impact could be more clearly constrained if specific sources were identified and if the molecular-level composition of DON were better understood. In this work, the...
Meteorological variables associated with deep slab avalanches on persistent weak layers
Alex Marienthal, Jordy Hendrikx, Karl W. Birkeland, Kathryn M. Irvine
2014, Conference Paper, Proceedings, International Snow Science Workshop, Banff, 2014
Deep slab avalanches are a particularly challenging avalanche forecasting problem. These avalanches are typically difficult to trigger, yet when they are triggered they tend to propagate far and result in large and destructive avalanches. For this work we define deep slab avalanches as those that fail on persistent weak layers...
Spatio-temporal patterns and climate variables controlling of biomass carbon stock of global grassland ecosystems from 1982 to 2006
Jiangzhou Xia, Shuguang Liu, Shunlin Liang, Yang Chen, Wenfang Xu, Wenping Yuan
2014, Remote Sensing (6) 1783-1802
Grassland ecosystems play an important role in subsistence agriculture and the global carbon cycle. However, the global spatio-temporal patterns and environmental controls of grassland biomass are not well quantified and understood. The goal of this study was to estimate the spatial and temporal patterns of the global grassland biomass and...
A design for a sustained assessment of climate forcings and feedbacks on land use land cover change
Thomas Loveland, Rezaul Mahmood
2014, Bulletin of the American Meteorological Society (95) 1563-1572
Land use and land cover change (LULCC) significantly influences the climate system. Hence, to prepare the nation for future climate change and variability, a sustained assessment of LULCC and its climatic impacts needs to be undertaken. To address this objective, not only do we need to determine contemporary trends in...
13.3 – Stable Isotope Geochemistry of Mineral Deposits
W.C. Pat Shanks III
2014, Book chapter, Reference module in earth systems and environmental sciences: Treatise on geochemistry (Second Edition)
In this chapter, the intent is to summarize the results of traditional stable isotope studies (mainly H, B, O, C, and S) that have greatly contributed to the understanding of ore-forming processes over the last 60 years and to provide an up-to-date assessment of the application of new nontraditional isotope...
Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska
Jonathan M.G. Glen, Darcy McPhee, Paul A. Bedrosian
2014, Conference Paper, Proceedings, Thirty-Ninth Workshop on Geothermal Reservoir Engineering
Pilgrim Hot Springs, located on the Seward Peninsula in west-central Alaska, is characterized by hot springs, surrounding thawed regions, and elevated lake temperatures. The area is of interest because of its potential for providing renewable energy for Nome and nearby rural communities. We performed ground and airborne geophysical investigations of...