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Abundance Of Ammonia-Oxidizing Archaea And Bacteria Along An Estuarine Salinity Gradient In Relationship To Potential Nitrification Rates, Anne E. Bernhard, Zachary C. Landry, Alison Blevins, José R. De La Torre, Anne E. Giblin, David A. Stahl Feb 2010

Abundance Of Ammonia-Oxidizing Archaea And Bacteria Along An Estuarine Salinity Gradient In Relationship To Potential Nitrification Rates, Anne E. Bernhard, Zachary C. Landry, Alison Blevins, José R. De La Torre, Anne E. Giblin, David A. Stahl

Biology Faculty Publications

Abundance of ammonia-oxidizing Archaea (AOA) was found to be always greater than that of ammonia-oxidizing Bacteria along an estuarine salinity gradient, and AOA abundance was highest at intermediate salinity. However, AOA abundance did not correlate with potential nitrification rates. This lack of correlation may be due to methodological limitations or alternative energy sources.


Our Places To Tell Stories: Preliminary Program Springs Preserve, Public Lands Institute Feb 2010

Our Places To Tell Stories: Preliminary Program Springs Preserve, Public Lands Institute

Our Places to Tell Stories

Our Places Tell Stories is an innovative conference for educators and others working at public lands, schools, nature centers, museums, zoos, aquaria, and all nature and heritage rich places.

This list of presentations represents a preliminary program of sessions. A final program will be emailed to all registrants prior to the conference. Thank you for your interest, and we look forward to seeing you at the Springs!


Estimation Of Vertical Groundwater Fluxes Into A Streambed Through Continuous Temperature Profile Monitoring And The Relationship Of Groundwater Fluxes To Coaster Brook Trout Spawning Habitat , Matthew Van Grinsven Jan 2010

Estimation Of Vertical Groundwater Fluxes Into A Streambed Through Continuous Temperature Profile Monitoring And The Relationship Of Groundwater Fluxes To Coaster Brook Trout Spawning Habitat , Matthew Van Grinsven

Dissertations, Master's Theses and Master's Reports - Open

We hypothesized that the spatial distribution of groundwater inflows through river bottom sediments is a critical factor associated with the selection of coaster brook trout (a life history variant of Salvelinus fontinalis,) spawning sites. An 80-m reach of the Salmon Trout River, in the Huron Mountains of the upper peninsula of Michigan, was selected to test the hypothesis based on long-term documentation of coaster brook trout spawning at this site. Throughout this site, the river is relatively similar along its length with regard to stream channel and substrate features. A monitoring well system consisting of an array of 27 …


Interactions Among Top-Down Regulators In A Temperate Forest Floor Ecosystem;Effects On Macrofauna, Mesofauna, Microbes And Litter Decay, Cari-Ann M. Hickerson Jan 2010

Interactions Among Top-Down Regulators In A Temperate Forest Floor Ecosystem;Effects On Macrofauna, Mesofauna, Microbes And Litter Decay, Cari-Ann M. Hickerson

ETD Archive

High species diversity and complexity of forest-floor food webs present a challenge for understanding the role of species interactions (e.g. competition and predation) as regulatory mechanisms for ecosystem processes such as decomposition and nutrient cycling. In particular, we understand very little about the roles of forest-floor predators in regulating diversity and abundance of lower trophic levels and ecosystem processes. However, ecological theory and several studies suggest that interactions among intraguild predators (IGP) may be important controls of diversity and abundance of organisms and detritus in lower trophic levels within food webs. A key prediction is that interactions among predators weaken …


Fall 2010, Nsu Oceanographic Center Jan 2010

Fall 2010, Nsu Oceanographic Center

Currents

No abstract provided.


Comparative Morphology Of Two Sympatric Species Of Hedgehog In Ikh Nart Nature Reserve, Mongolia, Richard P. Reading, David Kenny, Sodnomphil Batdorj, James Murdoch Jan 2010

Comparative Morphology Of Two Sympatric Species Of Hedgehog In Ikh Nart Nature Reserve, Mongolia, Richard P. Reading, David Kenny, Sodnomphil Batdorj, James Murdoch

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Daurian hedgehog (Mesechinus dauuricus) and long-eared hedgehog (Hemiechinus auritus) inhabit Ikh Nart Nature Reserve, Mongolia and both species appear to occupy similar niches. We gathered morphological measurements to test for differences between species and sexes. We hoped to gain insight into the mechanisms that allow the species to coexist. We collected morphometric data from 10 long-eared hedgehogs (6 male, 4 female) and 18 Daurian hedgehogs (10 male, 7 female, and 1 unknown sex). Only total body length in Daurian hedgehogs differed significantly between males and females. Otherwise, we found no significant differences between morphometric measures of …


Pathogenic And Opportunistic Microorganisms In Caves, Valme Jurado, Leonila Laiz, Veronica Rodriguez-Nava, Patrick Boiron, Bernardo Hermosin, Sergio Sanchez-Moral, Cesareo Saiz-Jimenez Jan 2010

Pathogenic And Opportunistic Microorganisms In Caves, Valme Jurado, Leonila Laiz, Veronica Rodriguez-Nava, Patrick Boiron, Bernardo Hermosin, Sergio Sanchez-Moral, Cesareo Saiz-Jimenez

International Journal of Speleology

With today’s leisure tourism, the frequency of visits to many caves makes it necessary to know about possible potentially pathogenic microorganisms in caves, determine their reservoirs, and inform the public about the consequences of such visits. Our data reveal that caves could be a potential danger to visitors because of the presence of opportunistic microorganisms, whose existence and possible development in humans is currently unknown.


Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters Jan 2010

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte River …


Understanding The Use Of Barrier Islands As Nesting Habitat For Louisiana Birds Of Concern, Cecilia Marie Leumas Jan 2010

Understanding The Use Of Barrier Islands As Nesting Habitat For Louisiana Birds Of Concern, Cecilia Marie Leumas

LSU Master's Theses

Colonial nesting seabirds are threatened by habitat loss and degradation, human disturbance, predation, and climate change. Several species of conservation concern concentrate high percentages of their total U.S. populations in Louisiana breeding colonies. We studied seabirds, including Royal Terns, Sandwich Terns, and Black Skimmers, nesting on Isles Dernieres barrier islands along the Gulf coast of Louisiana. Two of the four islands in this chain host extensive seabird colonies and two do not. We used an experimental approach to test the hypothesis that large terns and skimmers are prevented from nesting on Trinity Island, the largest of the Isles Dernieres, by …


Image Analysis For Water Surface & Subsurface Feature Detection In Shallow Waters, Charles R. Bostater Jr., James Jones, Heather Frystacky, Mate Kovacs, Oszkar Jozsa Jan 2010

Image Analysis For Water Surface & Subsurface Feature Detection In Shallow Waters, Charles R. Bostater Jr., James Jones, Heather Frystacky, Mate Kovacs, Oszkar Jozsa

Ocean Engineering and Marine Sciences Faculty Publications

Carefully collected airborne imagery demonstrates the ability to see water surface features as well as shallow bottom features such as submerged vegetation and manmade targets. Traditional photogrammetric imagery and airborne digital imagery both suffer from a loss in image clarity due to a number of factors, including capillary and small gravity waves, the water column or in-situ constituents. The use of submerged as well as surface man-made calibration targets deployed during airborne or in-situ subsurface image acquisitions forms a preliminary basis for correcting imagery in order to improve subsurface and surface features and their detection. Methods presented as well as …


The Role Of Skeletal Development In Body Size Evolution Of Two North American Frogs, Sarah Beth Havens Jan 2010

The Role Of Skeletal Development In Body Size Evolution Of Two North American Frogs, Sarah Beth Havens

Masters Theses

"In order to better understand the evolution of miniaturization in Acris blanchardi, a North American Hylid with a unique life history and of ecological interest in the United States. The development and ossification sequences of 48 larvae, 5 juveniles and 5 adult A. blanchardi were examined. The adult was described by Maglia et al. (2007) to be a miniature and to display morphological novelties. In addition, 44 larvae, 2 juvenile and 5 adults of Pseudacris crucifer a closely related frog that has been suggested to be a miniature, were examined. The cranial and postcranial adult elements of this species, as …


Undergraduate And Graduate Programs In Environmental Science At Unlv, Scott R. Abella Jan 2010

Undergraduate And Graduate Programs In Environmental Science At Unlv, Scott R. Abella

Public Policy and Leadership Faculty Research

The School of Environmental and Public Affairs at UNLV houses B.A. and B.S. degrees in Environmental Studies and M.S. and PhD degrees in Environmental Science. These degrees are flexible, multi-purpose, interdisciplinary programs that can be tailored for both breadth and depth.


Forest Edge Effects On The Behavioral Ecology Of L'Hoest's Monkey (Cercopithecus Lhoesti) In Bwindi Impenetrable National Park, Uganda, Tharcisse Ukizintambara Jan 2010

Forest Edge Effects On The Behavioral Ecology Of L'Hoest's Monkey (Cercopithecus Lhoesti) In Bwindi Impenetrable National Park, Uganda, Tharcisse Ukizintambara

Antioch University Dissertations & Theses

Forest edges are associated with forest edge effects that result from changes in physical features of the habitat, predator species and number, and prominence of human activities and other disturbances that can have direct or indirect impact on the distribution, ecology, and fitness of forest plant and animal species. I conducted a literature review on edge effects on primate species and came up with a classification of primate species in three general categories " thriving, sensitive and resilient species to edge effects " based on behavioral and demographic responses.

In Bwindi Impenetrable National Park, edge effects followed non-monotonic patterns (wave-like) …


Hydrological Characteristics Of A Large-Scale Flooding And Draining Experiment, Barrow, Alaska, Edith Jaurrieta De Velasco Jan 2010

Hydrological Characteristics Of A Large-Scale Flooding And Draining Experiment, Barrow, Alaska, Edith Jaurrieta De Velasco

Open Access Theses & Dissertations

The Arctic appears to be affected by climate change more so than any other region on Earth. Some of the most significant climate change impacts reported for the Arctic are associated with dramatic shifts in the hydrologic regime of terrestrial ecosystems. Understanding the hydrologic processes that are associated with different components of arctic terrestrial ecosystems is important because water in the form of snow or rain influences a range of properties and processes such as land-atmosphere energy and trace gas fluxes, nutrient cycling, ecosystem dynamics, biodiversity, periglacial processes and surface albedo. Furthermore, plants, animals, and native people of the Arctic …


The Transition Zone: Impact Of Riverbanks On Emergent Dragonfly Nymphs. Implications For Riverbank Restoration And Management, Kirsten Hope Martin Jan 2010

The Transition Zone: Impact Of Riverbanks On Emergent Dragonfly Nymphs. Implications For Riverbank Restoration And Management, Kirsten Hope Martin

Antioch University Dissertations & Theses

The use of riprap in the restoration and stabilization of riverine landscapes is an issue of concern for many ecologists. While current methods of bank stabilization, especially those involving the placement of rocks (riprap) along the waterline, are effective in controlling erosion their presence changes habitat components (slope, substrate composition, near-shore river velocity) at the river-land interface. The additional impacts of river current, water temperature, soil composition, slope, and water level fluctuation, may further imperil emerging nymphs. The purpose of this research is to document the effects of riprap, location (upriver or downriver of hydroelectric intake/outtake facilities), water level fluctuation, …


Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy Jan 2010

Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy

LSU Master's Theses

Louisiana’s estuaries and coastal waters play an important role in providing habitat for several estuarine-dependent species and also serve as a nursery for the juveniles of several other species. The current rate of land loss in Louisiana and the decline of estuarine-dependent species force us to improve our understanding of the recruitment of these species into Louisiana’s estuaries. Habitat suitabilities were developed for several fish species of concern (SOC) and other estuarine-dependent species across three environmental gradients, abundance patterns were developed for seasons, five-year intervals, and coastal study areas (CSAs). Chi-square analyses and ANOVAs were then used to test for …


From The Bronx Into The Wild! My Adventurous Experience At The Bronx Zoo, Lauren Noll Dec 2009

From The Bronx Into The Wild! My Adventurous Experience At The Bronx Zoo, Lauren Noll

Student Theses 2001-2013

Many people defend zoos, claiming that they provide great opportunities in education, scientific research, and the overall preservation of wildlife worldwide. However, many people will take the opposing side, arguing that it is wrong to deprive animals of their natural habitats and lifestyles. One of the greatest controversies of our time pertains to the moral issues associated with keeping animals in captivity, such as in zoos and aquariums.


Extraction And Analysis Of Coral Reef Core Samples From Broward County, Florida., Anastasios Stathakopoulos Dec 2009

Extraction And Analysis Of Coral Reef Core Samples From Broward County, Florida., Anastasios Stathakopoulos

HCNSO Student Theses and Dissertations

The reefs off Broward County exist as three shore-parallel, sequentially deeper terraces named the "inner", "middle", and "outer" reefs and also a shallower, nearshore ridge complex. These structures span the continental coast of southeast Florida from Palm Beach County to southern Miami-Dade County and were characterized as relict, early Holocene shelf-edge and mid-shelf reefs along with limestone ridges. Presently, the reefs are colonized by a fauna characteristic of West Atlantic/Caribbean reef systems. Scleractinian coral cover is low except for a few dense patches of Acropora cervicornis, while Acropora palmata is absent except for a few individual living colonies.

Coral …


Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood Oct 2009

Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96h, and solutions were analyzed for ammonium, …


Enhancing Ais To Improve Whale-Ship Collision Avoidance And Maritime Security, Philip A. Mcgillivary, Kurt Schwehr, Kevin Fall Oct 2009

Enhancing Ais To Improve Whale-Ship Collision Avoidance And Maritime Security, Philip A. Mcgillivary, Kurt Schwehr, Kevin Fall

Center for Coastal and Ocean Mapping

Whale-ship strikes are of growing worldwide concern due to the steady growth of commercial shipping. Improving the current situation involves the creation of a communication capability allowing whale position information to be estimated and exchanged among vessels and other observation assets. An early example of such a system has been implemented for the shipping lane approaches to the harbor of Boston, Massachusetts where ship traffic transits areas of the Stellwagen Bank National Marine Sanctuary frequently used by whales. It uses the Automated Identification Systems (AIS) technology, currently required for larger vessels but becoming more common in all classes of vessels. …


First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson Oct 2009

First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson

Virginia Journal of Science

During the fall of 2007, Centropris philadelphica (rock seabass) and Hypleurochilus geminatus (Crested blenny) were collected from Chesapeake Bay. These captures are significant as they represent the first substantiated record of C. philadelphica from Chesapeake Bay and only the second and third validated records of H. geminatus. Additionally, the first record of H. geminatus from Chesapeake Bay was only recently recognized since the specimen had been previously misidentified as Parablennius marmoreus (seaweed blenny). The collection of seven individuals of H. geminatus in 2007, from two locations, indicates that the species may be resident within the Chesapeake Bay estuary.


Phenotopic Plasticity Of Leaf Shape Along A Temperature Gradient In Acer Rubrum, Dana L. Royer, Laura A. Meyerson, Kevin M. Robertson, Jonathan M. Adams Oct 2009

Phenotopic Plasticity Of Leaf Shape Along A Temperature Gradient In Acer Rubrum, Dana L. Royer, Laura A. Meyerson, Kevin M. Robertson, Jonathan M. Adams

Natural Resources Science Faculty Publications

Both phenotypic plasticity and genetic determination can be important for understanding how plants respond to environmental change. However, little is known about the plastic response of leaf teeth and leaf dissection to temperature. This gap is critical because these leaf traits are commonly used to reconstruct paleoclimate from fossils, and such studies tacitly assume that traits measured from fossils reflect the environment at the time of their deposition, even during periods of rapid climate change. We measured leaf size and shape in Acer rubrum derived from four seed sources with a broad temperature range and grown for two years in …


Forensic Bird-Strike Identification Techniques Used In An Accident Investigation At Wiley Post Airport, Oklahoma, 2008, Carla J. Dove, Nor Faridah Dahlan, Marcy Heacker Oct 2009

Forensic Bird-Strike Identification Techniques Used In An Accident Investigation At Wiley Post Airport, Oklahoma, 2008, Carla J. Dove, Nor Faridah Dahlan, Marcy Heacker

Human–Wildlife Interactions

On March 4, 2008, a Cessna Citation 1 (Model 500) crashed in a wooded area near Wiley Post Airport, Oklahoma, killing all 5 people on board. This paper describes the detailed forensic methods and expertise used by the Smithsonian Institution’s Feather Identification Lab to identify the bird that caused this bird-strike incident. We used standard methods of whole-feather analysis, microscopic examination, and DNA barcoding in this case to identify American white pelican (Pelecanus erythrorhynchos) as the bird species involved in this fatal crash. We also report the importance of proper field investigation and evidence collection for accurate results, …


A Decade Of U.S. Air Force Bat Strikes, Suzanne C. Peurach, Carla J. Dove, Laura Stepko Oct 2009

A Decade Of U.S. Air Force Bat Strikes, Suzanne C. Peurach, Carla J. Dove, Laura Stepko

Human–Wildlife Interactions

From 1997 through 2007, 821 bat strikes were reported to the U.S. Air Force (USAF) Safety Center by aircraft personnel or ground crew and sent to the National Museum of Natural History, Smithsonian Institution, for identification. Many samples were identified by macroscopic and or microscopic comparisons with bat specimens housed in the museum and augmented during the last 2 years by DNA analysis. Bat remains from USAF strikes during this period were received at the museum from 40 states in the United States and from 20 countries. We confirmed that 46% of the strikes were caused by bats, but we …


Multiproxy Lake Sediment Records At The Northern And Southern Boundaries Of The Aspen Parkland Region Of Manitoba, Canada, Rebecca Teed, Charles Umbanhower, Philip Camill Sep 2009

Multiproxy Lake Sediment Records At The Northern And Southern Boundaries Of The Aspen Parkland Region Of Manitoba, Canada, Rebecca Teed, Charles Umbanhower, Philip Camill

Earth and Environmental Sciences Faculty Publications

Aspen parkland in central Canada may change substantially with increased warming and aridity as prairies replace forests, fire return intervals decrease and lake levels decline. We examined the relationships among vegetation, climate, fire and lake-ecosystem properties using lake sediment cores from the current northern and southern boundaries of the aspen parkland in southwestern Manitoba. We analyzed pollen, charcoal, sediment magnetics, biogenic silica, phosphorus, grain size and LOI, and dated the cores using 210Pb and 14C (AMS, calibrated). The Jones Lake record, from the southern edge of the parkland, began considerably earlier (~11 000 cal. BP) than the Mallard …


Biofuels: Cultivating Energy, Not Invasive Species, Invasive Species Advisory Committee Aug 2009

Biofuels: Cultivating Energy, Not Invasive Species, Invasive Species Advisory Committee

National Invasive Species Council

Biofuels: Cultivating Energy, not Invasive Species, approved by ISAC on August 11, 2009

ISSUE

To provide alternatives to petroleum-based energy, the United States government has mandated a greater proportion of plant-based biofuels be integrated into its energy portfolio. However, certain plant species being proposed for biofuel production in the United States are invasive species or are likely to escape cultivation and become invasive. United States Executive Order (EO) 131121 defines invasive species as “alien [non-native] species whose introduction does or is likely to cause economic or environmental harm or harm to human health” and states: “Each Federal agency whose actions …


The Effects Of Physical Activity And Nutrient Intake On The Risk Of Hip Fracture : Results From The Adventist Health Study-2, Wen-Ling Liao Aug 2009

The Effects Of Physical Activity And Nutrient Intake On The Risk Of Hip Fracture : Results From The Adventist Health Study-2, Wen-Ling Liao

Loma Linda University Electronic Theses, Dissertations & Projects

This is a two year of follow up study of Adventist Health Study-2 (AHS-2). We assessed the association between physical activity, nutrient intake and risk of hip fracture among peri- and post menopausal Caucasian women using unconditional logistic regression models. All subjects completed a lifestyle questionnaire which including information of physical activity and frequency and portion size of food intake at enrollment into the study (2002-2007). The “Bi-Annual Hospitalization History” questionnaire which included a question about hip fractures due to minor trauma/falls was sent to subjects approximately two years after enrollment, with a response rat of 82.84%. In this cohort, …


Discreet Dynamical Population Models : Higher Dimensional Pioneer-Climax Models, Yogesh Joshi May 2009

Discreet Dynamical Population Models : Higher Dimensional Pioneer-Climax Models, Yogesh Joshi

Dissertations

There are many population models in the literature for both continuous and discrete systems. This investigation begins with a general discrete model that subsumes almost all of the discrete population models currently in use. Some results related to the existence of fixed points are proved. Before launching into a mathematical analysis of the primary discrete dynamical model investigated in this dissertation, the basic elements of the model - pioneer and climax species - are described and discussed from an ecological as well as a dynamical systems perspective. An attempt is made to explain why the chosen hierarchical form of the …


Effects Of A Spatially And Temporally Predictable Chlorophyll Maximum On Bottlenose Dolphin Distribution In A South Carolina Estuary, Steven W. Thornton May 2009

Effects Of A Spatially And Temporally Predictable Chlorophyll Maximum On Bottlenose Dolphin Distribution In A South Carolina Estuary, Steven W. Thornton

Honors Theses

Numerous studies have focused on the complex relationship between phytoplankton and zooplankton in estuarine environments, but few have scrutinized the effects of this connection on organisms in higher trophic levels. This study examined chlorophyll a concentrations and zooplankton densities in North Inlet, South Carolina, a site where a stable chlorophyll a maximum has been documented to exist at low tide, to determine if they influenced the distribution of resident bottlenose dolphins (Tursiops truncatus). We hypothesized that patterns of estuarine circulation in the salt marsh serve to concentrate phytoplankton and zooplankton predictably in time and space, and that these patterns influence …


Center Of Ecological Studies Feasibility Project, Suzanne Williams, Jill Leonard May 2009

Center Of Ecological Studies Feasibility Project, Suzanne Williams, Jill Leonard

Grant

No abstract provided.