Oceanography and Atmospheric Sciences and Meteorology Commons^™

Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen

Natural Resource Management Faculty Publications

The Prairie Pothole Region (PPR) of North America is a globally important resource that provides abundant and valuable ecosystem goods and services in the form of biodiversity, groundwater recharge, water purification, flood attenuation, and water and forage for agriculture. Numerous studies have found these wetlands, which number in the millions, to be highly sensitive to climate variability. Here, we compare wetland conditions between two 30-year periods (1946–1975; 1976–2005) using a hindcast simulation approach to determine if recent climate warming in the region has already resulted in changes in wetland condition. Simulations using the WETLANDSCAPE model show that 20th century climate …

Understanding Basin Specific Life History Characteristics Of Lake Mead Quagga Mussels (Dreissena Bugensis) And A Potential Treatment Using Uv Radiation In Laboratory Studies, Melissa Thaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

The quagga mussel (Dreissena bugensis) is an aquatic invasive species that is spreading throughout Lake Mead and other western waterways. Unlike their native waters in Eurasia, Lake Mead exhibits year round warm temperatures, high calcium levels and a lack of natural predators, all of which are very favorable conditions for their growth and spread. Dreissena bugensis reproduce and colonize hard surfaces rapidly, where they filter large amounts of water. They disrupt the aquatic food chain and interfere with infrastructure that is exposed to lake water. There is an urgent need to understand Dreissena bugensis life history characteristics within this new …

A Prototype Decision Support Tool For Ballast Water Risk Management Using A Combination Of Hydrodynamic Models And Agent-Based Modelling, Fleming T. Hansen, Jesper H. Andersen, Michael Potthof, Thomas Uhrenholdt, Hong D. Vo, Olof Lindén

NSBWO

We report the development of a prototype Decision Support Tool (DST) for modelling the risks of spreading of non-indegenous invasive species via ballast water. The DST constitutes of two types of models: A 3D hydrodynamical model calculates the currents in the North Sea and Danish Straits, and an agent-based model estimates the dispersal of selected model organisms with the prevailing currents calculated by the 3D hydrodynamical model. The analysis is concluded by a post processing activity, where scenarios of dispersal are combined into an interim estimate of connectivity within the study area. The latter can be used as a tool …

Marine Invertebrates: Communities At Risk, Jennifer A. Mather

Ecological Impacts of Climate Change Collection

Our definition of the word ‘animal’ centers on vertebrates, yet 99% of the animals on the planet are invertebrates, about which we know little. In addition, although the Census of Marine Life (COML.org) has recently conducted an extensive audit of marine ecosystems, we still do not understand much about the animals of the seas. Surveys of the best-known ecosystems, in which invertebrate populations often play a key role, show that the invertebrate populations are affected by human impact. Coral animals are the foundation of coral reef systems, which are estimated to contain 30% of the species in the ocean. Physical …

Integrating, Developing, And Testing Methods To Generate More Cohesive Approaches To Biogeographic Inference, Mallory Elizabeth Eckstut

UNLV Theses, Dissertations, Professional Papers, and Capstones

As a fundamental component of the developing discipline of conservation biogeography, broadscale analyses of biotic assembly and disassembly across multiple temporal and spatial scales provide an enhanced understanding of how geologic transformations and climate oscillations have shaped extant patterns of biodiversity. As with any scientific field, there are limitations in the case of biogeographic historical reconstructions. Historical reconstructions are only as robust as the theoretical underpinnings of the methods of reconstruction (including data collection, quality, analysis, and interpretation). Nevertheless, historical reconstructions of species distributions can help inform our understanding of how species respond to environmental change.

My dissertation takes a …

Soil Moisture Recognition And The Spatial Distribution Of Storm Activity In The Mojave Desert Using High-Resolution Aster And Modis Imagery For Thermophysical Mapping, Russell J. Skuse

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate models suggest that the Mojave Desert ecoregion is vulnerable to becoming drier in the future, and as the human population grows and development increases, environmental stresses will likely increase. Determining the spatial distribution and variation of soil moisture on a regional scale is an essential component to climate change, hydrologic, and habitat analyses. Soil permeability and sediment stability are characteristics that have been shown to be measurable from remote sensing observations. The primary objective of this project is to map the mechanical composition of the surface materials in the Mojave Desert ecoregion with implications for soil permeability, sediment stability, …

The Evaluation Of Water Storage In Death Valley Using Grace Satellite Data, Maile Sweigart

UNLV Theses, Dissertations, Professional Papers, and Capstones

As drought conditions spread across the United States, concerns over water supplies, water use, and water management policies are growing and possible contributing environmental factors are continually being scrutinized. This thesis examines Death Valley as an analog for Southern Nevada and utilizes NASA EOS data, combined with ancillary climate data, to assess the effect of decadal climate variability on groundwater storage in the Death Valley area. Historical climate data, combined with satellite imagery observations, were compiled and calculated for analyses. Conclusions derived from statistical analyses infer trends between GRACE (Gravity Recovery and Climate Experiment) satellite data and fluctuating levels of …

Understanding Effects Of Changes In Land Use, Environmental Parameters, Habitat Characteristics On The Great Basin Aquatic Invertebrates Using Ecological Stoichiometric Theory, Knut Mehler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many freshwater ecosystems in the Great Basin have undergone dramatic alteration over the past decades due to groundwater withdrawal, water diversion and changes in land use. These changes have affected benthic food web dynamics by altering the availability of chemical key elements for primary and secondary producers, by loss of biodiversity and extinction of endemic species. However, only few studies are available that addresses the link between changes in land use, habitat characteristics and its effects on benthic macroinvertebrates (BMI) communities comprehensively and little attention has been given to integrating physiochemical aspects to link ecosystem functions.

This dissertation analyzes the …

Implications For Soil Microbe Research: Investigations Into The Feasibility Of Dna Amplification From Stained Roots And Temporal Patterns In Arbuscular Mycorrhizal Fungal Communities., Catherine Ausland

Independent Study Project (ISP) Collection

Arbuscular mycorrhizal (AM) fungi are obligate biotrophs that form symbiotic relationships with 80% of vascular plants around the world. Because of their beneficial relationship with plants in almost all terrestrial ecosystems, the implication of utilizing AM fungi in ecological restorations is immense. The following investigations seek to increase knowledge of the community ecology of AM fungi in order to enhance the potential for use of AM in ecological restoration. The first investigation replicated a novel method of AM visualization in plant roots, utilizing ink and vinegar as less destructive staining agents, to determine whether molecular studies could be feasibly performed …

Uncoupling Between Dinitrogen Fixation And Primary Productivity In The Eastern Mediterranean Sea, Eyal Rahav, Barak Herut, Noga Stambler, Edo Bar-Zeev, Margaret R. Mulholland

OES Faculty Publications

In the nitrogen (N)-impoverished photic zones of many oceanic regions, prokaryotic organisms fixing atmospheric dinitrogen (N₂; diazotrophs) supply an essential source of new nitrogen and fuel primary production. We measured dinitrogen fixation and primary productivity (PP) during the thermally stratified summer period in different water regimes of the oligotrophic eastern Mediterranean Sea, including the Cyprus Eddy and the Rhodes Gyre. Low N₂ fixation rates were measured (0.8-3.2μmol N m-2 d-1) excluding 10-fold higher rates in the Rhodes Gyre and Cyprus Eddy (~20μmol N m^-2 d^-1). The corresponding PP increased from east to west (200-2500μmol …

Bulk Partitioning The Growing Season Net Ecosystem Exchange Of Co2 In Siberian Tundra Reveals The Seasonality Of Its Carbon Sequestration Strength, Benjamin R. K. Runkle, T. Sachs, C. Wille, E.-M. Pfeiffer, L. Kutzbach

Biological and Agricultural Engineering Faculty Publications and Presentations

This paper evaluates the relative contribution of light and temperature on net ecosystem CO2 uptake during the 2006 growing season in a polygonal tundra ecosystem in the Lena River Delta in Northern Siberia (72°22´ N, 126°30´ E). The occurrence and frequency of warm periods may be an important determinant of the magnitude of the ecosystem's carbon sink function, as they drive temperature-induced changes in respiration. Hot spells during the early portion of the growing season, when the photosynthetic apparatus of vascular plants is not fully developed, are shown to be more influential in creating positive mid-day surface-to-atmosphere net ecosystem CO2 …

Fall 2013, Nova Southeastern University

Currents

No abstract provided.

Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer

Electronic Theses and Dissertations

Sagebrush (Artemisia spp.) ecosystems constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. Disturbances continue to alter this ecosystem, with climate change possibly representing the greatest future disturbance risk. Improved ways to characterize and monitor gradual change in this ecosystem are vital to its future management. A new remote sensing sagebrush characterization approach was developed in Wyoming which integrates three scales of remote sensing to derive four primary continuous field components (bare ground, herbaceousness, litter, and shrub), and four secondary components (sagebrush, big sagebrush, Wyoming sagebrush, and shrub …

Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan

OES Faculty Publications

Dissolved inorganic phosphorus (DIP) concentrations in surface water of vast areas of the ocean are extremely low (<10 nM) and phosphorus (P) availability could limit primary productivity in these regions. We explore the use of oxygen isotopic signature of dissolved phosphate (δ¹⁸O_PO4) to investigate biogeochemical cycling of P in the Sargasso Sea, Atlantic Ocean. Additional techniques for studying P dynamics including ³³P-based DIP turnover time estimates and percent of cells expressing alkaline phosphatase (AP) activity as measured by enzyme-labeling fluorescence are also used. In surface waters, δ¹⁸O_PO4 values were lower than equilibrium by 3–6%, indicative of dissolved organic phosphorous (DOP) remineralization by extracellular enzymes. An isotope mass balance model using a variety of possible combinations of …

Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones

OES Faculty Publications

Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …

Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller

Open Access Theses & Dissertations

Arctic environments have gained interest recently due to their sensitivity to climate change. As warming has created longer growing seasons, extended ice-free periods as well as permafrost thaw, the production in freshwater ecosystems has the potential to be greatly impacted. It is hypothesized that as climate change and warming occurs, increases in primary production will occur and ponds will become carbon sinks. Net ecosystem production (NEP) was determined using phytoplankton and periphyton samples collected weekly during the growing season (June - August) from arctic tundra ponds near Barrow, Alaska. Enrichment with 14C was used to determine both weekly photosynthetic rates …

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

Gradients In Season, Latitude, And Sea Ice: Their Effect On Metabolism And Stable Isotopic Composition Of Antarctic Micronekton, Erica H. Ombres

USF Tampa Graduate Theses and Dissertations

Respiration, metabolic enzyme assays, and body composition parameters were measured in the Antarctic krill Euphausia superba during the summer, fall and winter on the Western Antarctic Peninsula (WAP). E. superba of all sizes decrease their metabolism from the summer to the winter. These same parameters were also measured along the WAP during the austral fall 2010. E. superba's enzyme activity indicated that there was a latitudinal gradient to the decline in metabolism along the WAP with the more northerly sites having significantly higher metabolic enzyme activities than the sites to the south.

Carbon (δ¹³C) and nitrogen (δ^{15 …}

Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown

Ecological Impacts of Climate Change Collection

Determining the underlying mechanisms responsible for species-specific responses to climate change is important from a species management perspective. The grey-headed flying-fox, Pteropus poliocephalus, is listed as vulnerable but it also a significant pest species for orchardists and thereby presents an interesting management conundrum. Over the last century, the abundance of the grey-headed flying-fox, P. poliocephalus, in Australia has decreased due to a variety of threatening processes but has increased in abundance in urban areas. These flying-foxes are highly susceptible to extreme heat events which are predicted to increase in the future under climate change scenarios. Exceptionally hot days result in …

Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich

Dissertations and Theses

This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with …

Moving Forward: Preventing Water Shortage For Nevada, Sandra Blandon, Brianna Lyon

Anthropology 100: Feast and Famine In a Global World Poster Assignment

Southern Nevada is located in the arid Mojave Desert, which averages about 4 inches of rain each year. Southern Nevada gets about 90% of its water supply from the Colorado River. Seven western states and Mexico share the river. This means that The Colorado River provides water to 25 million people.

Phylogenetics Links Monster Larva To Deep-Sea Shrimp., Heather D Bracken-Grissom, Darryl L Felder, Nicole L Vollmer, Joel W Martin, Keith A Crandall

Computational Biology Institute

Mid-water plankton collections commonly include bizarre and mysterious developmental stages that differ conspicuously from their adult counterparts in morphology and habitat. Unaware of the existence of planktonic larval stages, early zoologists often misidentified these unique morphologies as independent adult lineages. Many such mistakes have since been corrected by collecting larvae, raising them in the lab, and identifying the adult forms. However, challenges arise when the larva is remarkably rare in nature and relatively inaccessible due to its changing habitats over the course of ontogeny. The mid-water marine species Cerataspis monstrosa (Gray 1828) is an armored crustacean larva whose adult identity …

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending September 30, 2012, Margaret N. Rees

Limnological Studies

Continuation of Project 1

• The research effort titled Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay is ongoing.

Continuation of Project 2

• Additional content was contributed to the future NPS-funded U.S. Geological Survey Circular ‘state-of-the-science’ report for Lakes Mead and Mohave. UNLV performed a new co-editing and coordinating task related to this product as the major focus of this quarter’s effort; the master version of this report is on schedule for delivery to the editorial team during the first week of October 2012.

Modification Activities:

Extended Short-term Continued Limnological Assistance

Quagga Mussel Objectives:

• Most juvenile/adult quagga mussel …

Biodegradation Of Textile Dye Anthraquinone Vat Blue 4 By Pseudomonas Aeruginosa, Rajee Olaganathan, Jamila Patterson

Publications

Uncontaminated and Vat blue 4 contaminated soil were screened for heterotrophic bacterial population and the bacterial density were found to be 19.3 X 104 and 5.5 X 104 CFU/gm respectively. The bacterial genera of dye contaminated soil was dominated by Pseudomonas sp. (32.5 %) followed by Bacillus sp. (27.5 %), Aeromonas sp. (15.0 %), Micrococcus sp. (12.5 %) and Achromobacter sp. (12.5 %). The optimum inoculums load, pH and temperature were found to be 5%, 7 and 35oC respectively. The initial pH of the effluent prepared using Vat Blue 4 was 8.5. The free cells of P. aeruginosa reduced the …

Population Structure And Connectivity Of An Important Pelagic Forage Fish In The Antarctic Ecosystem, Pleuragramma Antarcticum In Relation To Large Scale Circulation, Jason W. Ferguson

OES Theses and Dissertations

Ocean circulation has been identified as a major process controlling the distribution of biological material in marine systems. Large-scale transport by the Antarctic Circumpolar Current (ACC), the Ross and Weddell Gyres, and the Antarctic Coastal Current can promote spatially complex population structure in the Southern Ocean through advection. Antarctic silverfish (Pleuragramma antarcticum), a pelagic, neutrally buoyant notothenioid fish species, are distributed around the shelf systems of Antarctica and are considered an important species rivaling krill as prey for many birds, seals, whales, and other fish. We asked whether silverfish are distributed in independent, discrete populations along the shelf systems of …

Climate's Role In Polar Bear Past [Letters], Kurt E. Galbreath, Joseph A. Cook, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Striking temporal concordance between the new date for divergence of polar bears and persistent freezing of the Arctic Ocean suggests that this may be one of relatively few instances in which a specific paleoclimatological episode can be convincingly linked to a specific evolutionary event, and it provides vivid demonstration of climatic forcing as a determinant of diversification in biological systems.

Will Extreme Climatic Events Facilitate Biological Invasions?, Jeffrey M. Diez, Carla M. D'Antonio, Jeffrey S. Dukes, Edwin D. Grosholz, Julian D. Olden, Cascade J.B. Sorte, Dana M. Blumenthal, Bethany A. Bradley, Regan I. Early, Inés Ibáñez, Sierra J. Jones, Joshua J. Lawler, Luke P. Miller

Faculty Publications, Biological Sciences

Extreme climatic events (ECEs) – such as unusual heat waves, hurricanes, floods, and droughts – can dramatically affect ecological and evolutionary processes, and these events are projected to become more frequent and more intense with ongoing climate change. However, the implications of ECEs for biological invasions remain poorly understood. Using concepts and empirical evidence from invasion ecology, we identify mechanisms by which ECEs may influence the invasion process, from initial introduction through establishment and spread. We summarize how ECEs can enhance invasions by promoting the transport of propagules into new regions, by decreasing the resistance of native communities to establishment, …

Modeling The Dispersion Of Eastern Oyster Larvae (Crassostrea Virginica) And Its Effects On The Movement Of Disease Resistant Genes In The Delaware Bay Estuary, Diego A. Narvaez

OES Theses and Dissertations

This study combines several models to address two primary research questions. How does the interaction of larval biology and environmental variability determine the spatial distribution of oyster larvae in Delaware Bay? What is the role of larval dispersion in the transference of disease-resistant genes? The particle-tracking module in the Regional Ocean Modeling System (ROMS) was converted into an Individual-Based model representing Eastern oyster larvae that has growth and vertical migration. Exchange of larvae between natural oyster reefs was estimated and used in an Individual-Based genetic model that simulates the genetic structure of eastern oysters. Particles were released from a number …

Links From Mantle To Microbe At The Lau Integrated Study Site: Insights From A Back-Arc Spreading Center, Margaret K. Tivey, Erin Becker, Roxanne Beinart, Charles R. Fisher, Peter Girguis, Charles H. Langmuir, Peter J. Michael, Anna-Louise Reysenbach

Biology Faculty Publications and Presentations

The Lau Integrated Study Site (ISS) has provided unique opportunities for study of ridge processes because of its back-arc setting in the southwestern Pacific. Its location allows study of a biogeographical province distinct from those of eastern Pacific and mid-Atlantic ridges, and crustal compositions along the ridge lie outside the range of mid-ocean ridge crustal compositions. The Lau ISS is located above a subduction zone, at an oblique angle. The underlying mantle receives water and other elements derived from the downgoing lithospheric slab, with an increase in slab influence from north to south. Water lowers the mantle melting temperature and …

Winter 2012, Nsu Oceanographic Center

Currents

No abstract provided.