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2014

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Articles 511 - 540 of 621

Full-Text Articles in Ecology and Evolutionary Biology

Rates And Modes Of Sequence Evolution In Various Lineages Within Chenopodiaceae, James Andrew Naeger Jan 2014

Rates And Modes Of Sequence Evolution In Various Lineages Within Chenopodiaceae, James Andrew Naeger

Wayne State University Theses

Sexual dimorphism in domesticated spinach, Spinacia oleracea, is thought to be determined by differential expression of floral organ identity genes. We examined the floral organ morphologies of seven species in the Chenopodiaceae, including two wild species of spinach, in order to gain insight into the evolution of floral reproductive strategy in this clade. The species within the Anserineae demonstrate extensive evolution in floral morphology and reproductive strategy, and Spinacia is unique for having been domesticated rather recently and for being dioecious. We found C. album to be hermaphroditic, C. foliosum and M. nuttalliana to be gynomonoecious, while C. bonus-henricus …


Assessing Grazing Impacts On A Tropical Dry Forest System In Madagascar Through Vegetation, Satellite Image, Lemur Occupancy, And Acoustic Analysis, Lyndsay Lee Rankin Jan 2014

Assessing Grazing Impacts On A Tropical Dry Forest System In Madagascar Through Vegetation, Satellite Image, Lemur Occupancy, And Acoustic Analysis, Lyndsay Lee Rankin

Theses, Dissertations and Capstones

The ability to assess the quality or ecological value of a landscape is a useful tool in effective conservation and natural resource management. Ecosystem biodiversity and functionality are reduced when human activities cause habitat alteration and/or fragmentation. Compromised habitats are unlikely to support naturally occurring communities or healthy ecosystem functions. Conservation scientists have historically concentrated their efforts on large, intact habitats with little human disturbance; the conservation value of small and/or disturbed areas has been comparatively overlooked. One limitation may be a lack of tools to identify disturbed areas with conservation value. Techniques that allow researchers to assess the habitat …


Monitoring Ship Noise To Assess The Impact Of Coastal Developments On Marine Mammals, Nathan D. Merchant, Enrico Pirotta, Tim R. Barton, Paul M. Thompson Jan 2014

Monitoring Ship Noise To Assess The Impact Of Coastal Developments On Marine Mammals, Nathan D. Merchant, Enrico Pirotta, Tim R. Barton, Paul M. Thompson

Biology - All Scholarship

The potential impacts of underwater noise on marine mammals are widely recognised, but uncertainty over variability in baseline noise levels often constrains efforts to manage these impacts. This paper characterises natural and anthropogenic contributors to underwater noise at two sites in the Moray Firth Special Area of Conservation, an important marine mammal habitat that may be exposed to increased shipping activity from proposed offshore energy developments. We aimed to establish a pre-develop- ment baseline, and to develop ship noise monitoring methods using Automatic Identification System (AIS) and time-lapse video to record trends in noise levels and shipping activity. Our results …


Evolution, Snakes, And God: A Brief Argument For Agreement, Jessica Stanze Jan 2014

Evolution, Snakes, And God: A Brief Argument For Agreement, Jessica Stanze

A with Honors Projects

Comparing the evolution and religious connotations of the snake, this short essay suggests that evolutionists and creationists might reach common ground if they attempted to collaborate.


The Distribution Of Fitness Effects Of Spontaneous Mutations In Vibrio Fischeri, Chelsea K. Jones Jan 2014

The Distribution Of Fitness Effects Of Spontaneous Mutations In Vibrio Fischeri, Chelsea K. Jones

Honors Theses and Capstones

Mutations are the ultimate source of the biological diversity on which natural selection acts, but the vast majority of these mutations are harmful. As such, mutations lead to disease states like cancer, extinction of small populations, and can drive pathogen evolution. Unfortunately, because mutations are rare and past studies have been subject to detection biases, very little is known about the distribution of fitness effects from naturally occurring mutations. In this study, we used mutation accumulation and full genome sequencing to capture naturally occurring mutations before they were exposed to the sieve of natural selection in Vibrio fischeri. We …


Wild Bees Preferentially Visit Rudbeckia Flower Heads With Exaggerated Ultraviolet Absorbing Floral Guides, Lisa Horth, Laura Campbell, Rebecca Bray Jan 2014

Wild Bees Preferentially Visit Rudbeckia Flower Heads With Exaggerated Ultraviolet Absorbing Floral Guides, Lisa Horth, Laura Campbell, Rebecca Bray

Biological Sciences Faculty Publications

Here, we report on the results of an experimental study that assessed the visitation frequency of wild bees to conspecific flowers with different sized floral guides. UV absorbent floral guides are ubiquitous in Angiosperms, yet surprisingly little is known about conspecific variation in these guides and very few studies have evaluated pollinator response to UV guide manipulation. This is true despite our rich understanding about learning and color preferences in bees. Historical dogma indicates that flower color serves as an important long-range visual signal allowing pollinators to detect the flowers, while floral guides function as close-range signals that direct pollinators …


Extinction Risk And Conservation Of The World's Sharks And Rays, Nicholas K. Dulvy, Sarah L. Fowler, John A. Musick, Rachel D. Cavanagh, Peter M. Kyne, Lucy R. Harrison, John K. Carlson, Lindsay N. K. Davidson, Sonja V. Fordham, Malcolm P. Francis, Caroline M. Pollock, Colin A. Simpfendorfer, George H. Burgess, Kent E. Carpenter, Leonard J. V. Compagno, David A. Ebert, Claudine Gibson, Michelle R. Heupel, Suzanne R. Livingstone, Jonnell C. Sanciangco, John D. Stevens, Sarah Valenti, William T. White Jan 2014

Extinction Risk And Conservation Of The World's Sharks And Rays, Nicholas K. Dulvy, Sarah L. Fowler, John A. Musick, Rachel D. Cavanagh, Peter M. Kyne, Lucy R. Harrison, John K. Carlson, Lindsay N. K. Davidson, Sonja V. Fordham, Malcolm P. Francis, Caroline M. Pollock, Colin A. Simpfendorfer, George H. Burgess, Kent E. Carpenter, Leonard J. V. Compagno, David A. Ebert, Claudine Gibson, Michelle R. Heupel, Suzanne R. Livingstone, Jonnell C. Sanciangco, John D. Stevens, Sarah Valenti, William T. White

Biological Sciences Faculty Publications

The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes-sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other …


Concordance Between Phylogeographic And Biogeographic Boundaries In The Coral Triangle: Conservation Implications Based On Comparative Analyses Of Multiple Giant Clam Species, Timery S. Deboer, Maria Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toha, Paul H. Barber Jan 2014

Concordance Between Phylogeographic And Biogeographic Boundaries In The Coral Triangle: Conservation Implications Based On Comparative Analyses Of Multiple Giant Clam Species, Timery S. Deboer, Maria Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toha, Paul H. Barber

Biological Sciences Faculty Publications

Marine habitats are in decline worldwide, precipitating a strong interest in marine conservation. The use of biogeographic data to designate ecoregions has had significant impacts on terrestrial conservation efforts. However, classification of marine environments into ecoregions has only become available in the last several years, based on biogeographic data supplemented by geomorphology, ocean currents, and water temperatures. Here we use a comparative phylogeographic approach to test for concordant phylogeographic patterns in three closely related species of Tridacna giant clams across the Coral Triangle, the most biodiverse marine region in the world and one of the most threatened. Data from a …


Within-Season Nest Reuse By Mountain Plovers (Charadrius Montanus) In Eastern Colorado, Lani T. Stinson, Victoria J. Dreitz Jan 2014

Within-Season Nest Reuse By Mountain Plovers (Charadrius Montanus) In Eastern Colorado, Lani T. Stinson, Victoria J. Dreitz

Wildlife Biology Faculty Publications

The Mountain Plover (Charadrius montanus) is a declining migratory shorebird that nests on shortgrass prairies across the western Great Plains. This ground-nesting species exhibits an uncommon split-clutch mating system, in which each member of a pair simultaneously incubates a nest and uniparental care continues throughout brood-rearing. We report on an observation of within-season nest reuse in this species. To our knowledge, this report includes the first documented occurrence of 2 different Mountain Plovers using the same nest cup in the same breeding season. Nest reuse could represent a time- and energy-saving strategy for renesting individuals.


A Coupled Geochemical And Biogeochemical Approach To Characterize The Bioreactivity Of Dissolved Organic Matter From A Headwater Stream, Rachel L. Sleighter, Rose M. Cory, Louis A. Kaplan, Hussain A.N. Abdulla, Patrick G. Hatcher Jan 2014

A Coupled Geochemical And Biogeochemical Approach To Characterize The Bioreactivity Of Dissolved Organic Matter From A Headwater Stream, Rachel L. Sleighter, Rose M. Cory, Louis A. Kaplan, Hussain A.N. Abdulla, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The bioreactivity or susceptibility of dissolved organic matter (DOM) to microbial degradation in streams and rivers is of critical importance to global change studies, but a comprehensive understanding of DOM bioreactivity has been elusive due, in part, to the stunningly diverse assemblages of organic molecules within DOM. We approach this problem by employing a range of techniques to characterize DOM as it flows through biofilm reactors: dissolved organic carbon (DOC) concentrations, excitation emission matrix spectroscopy (EEMs), and ultrahigh resolution mass spectrometry. The EEMs and mass spectral data were analyzed using a combination of multivariate statistical approaches. We found that 45% …


Prevalence Of The Amphibian Chytrid Fungus Among Zoo And Pet Store Collections In The Northeastern United States, Harrison D. Winters, Katherine M. Albertini, Laura E. Neely, Mizuki Takahashi Jan 2014

Prevalence Of The Amphibian Chytrid Fungus Among Zoo And Pet Store Collections In The Northeastern United States, Harrison D. Winters, Katherine M. Albertini, Laura E. Neely, Mizuki Takahashi

Faculty Journal Articles

No abstract provided.


A Stable Niche Assumption-Free Test Of Ecological Divergence, Mizuki Takahashi, Jonathan M. Eastman, Duane Griffin, Jason Baumsteiger, Matthew J. Parris, Andrew Storfer Jan 2014

A Stable Niche Assumption-Free Test Of Ecological Divergence, Mizuki Takahashi, Jonathan M. Eastman, Duane Griffin, Jason Baumsteiger, Matthew J. Parris, Andrew Storfer

Faculty Journal Articles

No abstract provided.


Stream Restoration Proposal 2014, Plum Run Tributary – West Branch, Jesse Mclaughlin, Greg Smith Jan 2014

Stream Restoration Proposal 2014, Plum Run Tributary – West Branch, Jesse Mclaughlin, Greg Smith

Biology Student Work

No abstract provided.


Exploring The Links Between Seasonal Variation And Spider Foraging, Thomas Edward Dantas Whitney Jan 2014

Exploring The Links Between Seasonal Variation And Spider Foraging, Thomas Edward Dantas Whitney

Theses and Dissertations--Entomology

According to optimal foraging theory, generalist predators, such as spiders, are thought to feed indiscriminately on prey according to its availability, especially when food is scarce. In contrast, generalists can display selective feeding decisions under regimes of high prey abundance, but few studies have tracked changes in prey choice on a seasonal basis under open field conditions. Additionally, adaptations to surviving winter have been largely ignored in the research of foraging behavior. To elucidate this, I monitored prey availability and collected common forest-dwelling wolf spiders for molecular gut-content analysis, in parallel for 18 months, to assess the temporal changes occurring …


Identifying Sources Of The Tragedy Of The Commons In Root Competition: A Spatially Explicit Simulation Model And Plants Grown In Transparent Growth Medium, R Deric Leith Miller Jan 2014

Identifying Sources Of The Tragedy Of The Commons In Root Competition: A Spatially Explicit Simulation Model And Plants Grown In Transparent Growth Medium, R Deric Leith Miller

Theses and Dissertations--Biology

Existing research shows that plants produce less root when growing alone than when growing in competition with other plants. When plants under root competition over-allocate resources to roots at the cost of reproduction, it represents a Tragedy of the Commons. I constructed simulation models to determine the circumstances likely to give rise to a Tragedy of the Commons, and explore mechanisms by which plants may solve it. I grew plants in nutrient-rich transparent gel, allowing me to quantify root growth and development without destructive sampling. My plants responded positively to additional space and the presence of a competitor at full …


Grassland Sustainability In Kentucky: Case Studies Quantifying The Effects Of Climate Change On Slug Herbivory In Pastures And Different Home Lawn Systems On Turf Greenhouse Gas Emissions, Daniel Adam Weber Jan 2014

Grassland Sustainability In Kentucky: Case Studies Quantifying The Effects Of Climate Change On Slug Herbivory In Pastures And Different Home Lawn Systems On Turf Greenhouse Gas Emissions, Daniel Adam Weber

Theses and Dissertations--Plant and Soil Sciences

Grasslands comprise the greatest biome by land area, are sensitive to environmental factors affected by climate change, and can impact future climate change through their ability to store and release greenhouse gasses (GHGs). I performed two studies: 1) evaluated the effects of increased temperature and precipitation on slug herbivory/abundance and pasture forage production; 2) quantified different homeowner lawn system effects on soil-to-atmosphere GHG emissions. Climate change will likely affect pasture forage production, with implications for slug herbivory and abundance. I found little evidence that slugs have or will have significant effects on pasture production or plant community. Warming altered the …


Bed-Site Selection By Neonatal White-Tailed Deer In Central North Dakota, Brian A. Schaffer, Jonathan A. Jenks, Troy Grovenburg, William F. Jensen Jan 2014

Bed-Site Selection By Neonatal White-Tailed Deer In Central North Dakota, Brian A. Schaffer, Jonathan A. Jenks, Troy Grovenburg, William F. Jensen

Natural Resource Management Faculty Publications

Understanding bed-site selection and vegetation characteristics provides valuable information for population management (Verme 1977, Huegel et al. 1985a, Nelson and Woolf 1987). Predation and other natural-caused mortalities of white-tailed deer (Odocoileus virginianus) neonates are most likely to occur within the first 60 days of life; a time period when selected habitat characteristics are vital to survival (Verme 1977, Huegel et al. 1985a, Nelson and Woolf 1987, Grovenburg et al. 2010). Prior to the study of Grovenburg et al. (2010), limited research had been completed on bed-site selection of neonatal white-tailed deer in the grasslands of the Northern Great Plains. In …


Nest Destruction Elicits Indiscriminate Con- Versus Heterospecific Brood Parasitism In A Captive Bird, Rachel C. Shaw, William E. Feeney, Mark E. Hauber Jan 2014

Nest Destruction Elicits Indiscriminate Con- Versus Heterospecific Brood Parasitism In A Captive Bird, Rachel C. Shaw, William E. Feeney, Mark E. Hauber

Publications and Research

Following nest destruction, the laying of physiologically committed eggs (eggs that are ovulated, yolked, and making their way through the oviduct) in the nests of other birds is considered a viable pathway for the evolution of obligate interspecific brood parasitism. While intraspecific brood parasitism in response to nest predation has been experimentally demonstrated, this pathway has yet to be evaluated in an interspecific context. We studied patterns of egg laying following experimental nest destruction in captive zebra finches, Taeniopygia guttata, a frequent intraspecific brood parasite. We found that zebra finches laid physiologically committed eggs indiscriminately between nests containing conspecific eggs …


Grizzly Bear Monitoring By The Heiltsuk People As A Crucible For First Nation Conservation Practice, William G. Housty, Anna Noson, Gerald W. Scoville, John Boulanger, Richard M. Jeo, Chris T. Darimont, Christopher E. Filardi Jan 2014

Grizzly Bear Monitoring By The Heiltsuk People As A Crucible For First Nation Conservation Practice, William G. Housty, Anna Noson, Gerald W. Scoville, John Boulanger, Richard M. Jeo, Chris T. Darimont, Christopher E. Filardi

All Faculty Scholarship for the College of the Sciences

Guided by deeply held cultural values, First Nations in Canada are rapidly regaining legal authority to manage natural resources. We present a research collaboration among academics, tribal government, provincial and federal government, resource managers, conservation practitioners, and community leaders supporting First Nation resource authority and stewardship. First, we present results from a molecular genetics study of grizzly bears inhabiting an important conservation area within the territory of the Heiltsuk First Nation in coastal British Columbia. Noninvasive hair sampling occurred between 2006 and 2009 in the Koeye watershed, a stronghold for grizzly bears, salmon, and Heiltsuk people. Molecular demographic analyses revealed …


Ecology Of The Squirrel Treefrog (Hyla Squirella) In Southern Arkansas, M. B. Connior, T. Fulmer, C. T. Mcallister, S. E. Trauth, C. R. Bursey Jan 2014

Ecology Of The Squirrel Treefrog (Hyla Squirella) In Southern Arkansas, M. B. Connior, T. Fulmer, C. T. Mcallister, S. E. Trauth, C. R. Bursey

Journal of the Arkansas Academy of Science

We conducted an ecological study of the Squirrel Treefrog, Hyla squirella near El Dorado, Union Co., Arkansas from May-Oct. 2013. We extended the known distribution by ~2 km and documented the first breeding occurring on 28 May and the first transformation of juveniles on 27 Aug. Three endoparasites were documented: Opalina sp., Nyctotherus cordiformis, and Physaloptera sp. larvae. We also provide information on endoparasites of Florida H. squirella as well as a summary of helminths of this frog.


Growth And Reproduction In The Ouachita Madtom (Noturus Lachneri) At The Periphery Of Its Distribution, R. Tumilson, J. O. Hardage Jan 2014

Growth And Reproduction In The Ouachita Madtom (Noturus Lachneri) At The Periphery Of Its Distribution, R. Tumilson, J. O. Hardage

Journal of the Arkansas Academy of Science

The Ouachita madtom (Noturus lachneri) occurs primarily in drainages of the upper Saline River and in a few small tributaries to the Ouachita River in Arkansas, USA. We collected specimens by hand and by use of aquarium dipnets on 29 occasions from 20 October 1999 through 25 July 2000 in Cooper Creek, presently a feeder creek into Lake Catherine on the Ouachita River. Total length was measured, reproductive attributes were noted, and individuals were released at the capture site (with exception of 3 gravid females retained to assess fecundity). We recognized 2 age (size) classes during most of the year …


Toad (Anura: Bufonidae) Limb Abnormalities From An Aquatic Site In Scott, Pulaski County, Arkansas, C. S. Thigpen, D. Beard, S. E. Trauth Jan 2014

Toad (Anura: Bufonidae) Limb Abnormalities From An Aquatic Site In Scott, Pulaski County, Arkansas, C. S. Thigpen, D. Beard, S. E. Trauth

Journal of the Arkansas Academy of Science

We collected and examined 16 Fowler’s toads, Anaxyrus fowleri, and one dwarf American toad, Anaxyrus americanus charlesmithi, in central Arkansas in 2011. Collection was initiated by observation of abnormal toads. Toads were euthanized, measured, photographed, and deposited in the Arkansas State University herpetological collection. Several toads were radiographed. We found various abnormalities in both forelimbs and hindlimbs and on both sides of the body. The causes of the abnormalities remain unknown and will require further studies to determine if the environment is imperiled.


Sustainability Policy’S Inherent Dilemmas – Exemplified Via Critical Examination Of The Las Vegas Metropolitan Sustainability Campaign, Kathryn A. Zimmerman Jan 2014

Sustainability Policy’S Inherent Dilemmas – Exemplified Via Critical Examination Of The Las Vegas Metropolitan Sustainability Campaign, Kathryn A. Zimmerman

All Master's Theses

In response to a dual problem of critical water scarcity and rapid population growth, leaders of metropolitan Las Vegas implemented a region-wide, internationally marketed sustainability campaign. Preliminary studies found that, while sustainability policy attains its rhetorical goals, solutions initiated not only perpetuate but also purposefully expand the original dual problem to justify continuous water resource acquisitions. To examine this sustainability conundrum constructed by leadership—problem-perpetuation rather than problem-resolution—a critical examination in resource management asked two basic questions: what is being sustained and by what means? Via this inquiry, specific processes by which leaders perpetuate problems can be identified; and, so-informed, new …


The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead Jan 2014

The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead

OES Theses and Dissertations

Understanding the population structure and patterns of connectivity in marine fishes is essential when making predictions about a species' resiliency and persistence in an increasingly changing environment. The Atlantic Menhaden Brevoortia tyrannus is a clupeid that plays a critical role in the marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before recruiting to the adult population and the contribution of each of …


Winter Survival Strategies Of Benthic Invertebrates In Temporary Habitats In A Northern Minnesota Lake, Cal Oldenburg Jan 2014

Winter Survival Strategies Of Benthic Invertebrates In Temporary Habitats In A Northern Minnesota Lake, Cal Oldenburg

Journal of Earth and Life Science

During the winter months in the northern hemisphere, above 40 degrees latitude, a freezing event occurs that can last several months. Some lakes may have large portions of the shallow littoral zone frozen completely solid down into the sediments. Invertebrates affected by these events have developed survival strategies to cope with the harsh environment. The two main strategies for invertebrates in these areas are to either migrate to a different area and recolonize the original area when it becomes available again, or to burrow into the sediments and withstand the freezing. A 1- month study took place on Lake Bemidji …


Small Tidal Channels Improve Foraging Opportunities For Calidris Shorebirds, Aileen K. Miller, Catherine E. De Rivera Jan 2014

Small Tidal Channels Improve Foraging Opportunities For Calidris Shorebirds, Aileen K. Miller, Catherine E. De Rivera

Environmental Science and Management Faculty Publications and Presentations

Estuarine intertidal habitats are heterogeneous, therefore migratory shorebirds are expected to forage in microhabitats where they can maximize their energy intake. Identifying proximate factors that migratory shorebirds use to accept or reject a particular habitat patch will help land managers make conservation and restoration decisions that provide the greatest benefits to shorebird populations during migration, a period of intense energy usage. We examined whether small semipermanent tidal channels were preferentially used by foraging Western Sandpipers (Calidris mauri) and Dunlins (C. alpina) during a spring migratory stopover in Bandon Marsh, an Oregon, USA, estuary. Further, we tested …


Investigating The Impacts Of Streambed Habitat Heterogeneity On Ecosystem Structure And Processes Using Basic And Applied Perspectives, James C. Olson Jan 2014

Investigating The Impacts Of Streambed Habitat Heterogeneity On Ecosystem Structure And Processes Using Basic And Applied Perspectives, James C. Olson

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

Stream restoration often focuses on increasing habitat heterogeneity to reverse ecosystem degradation. However, the connection between heterogeneity and ecosystem structure and processes is poorly understood. We looked to investigate this interaction from both applied and basic science perspectives. For the applied study, we examined two culvert replacements designed to mimic natural stream channels, to see if they were better at maintaining ecosystem processes within as well as upstream and downstream of culverts compared to non-replaced culverts. We measured three ecosystem processes (nutrient uptake, hydrologic characteristics, and coarse particulate organic matter retention) and found that stream simulation culvert restoration improved organic …


Analysis Of Populus Tremuloides Clonal Variation And Delineation In The Ottawa National Forest, Kristina N. Flesher Jan 2014

Analysis Of Populus Tremuloides Clonal Variation And Delineation In The Ottawa National Forest, Kristina N. Flesher

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

The technique of delineating Populus tremuloides (Michx.) clonal colonies based on morphology and phenology has been utilized in many studies and forestry applications since the 1950s. Recently, the availability and robustness of molecular markers has challenged the validity of such approaches for accurate clonal identification. However, genetically sampling an entire stand is largely impractical or impossible. For that reason, it is often necessary to delineate putative genet boundaries for a more selective approach when genetically analyzing a clonal population. Here I re-evaluated the usefulness of phenotypic delineation by: (1) genetically identifying clonal colonies using nuclear microsatellite markers, (2) assessing phenotypic …


Exploring Changes In Detrital Flocculent Layer Dynamics Due To Shifts In Macrophyte Communities In The Northern Everglades, Erin Leigh Mckenney Jan 2014

Exploring Changes In Detrital Flocculent Layer Dynamics Due To Shifts In Macrophyte Communities In The Northern Everglades, Erin Leigh Mckenney

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

A shift in plant communities of the Water Conservation Areas (WCAs) within the Everglades has been linked to changes in hydrology and high levels of nutrient loading from surrounding agicultural areas. This has resulted in the encroachment of dense cattail stands (Typha domingensis) into areas that had previously been a ridge and slough landscape populated primarily by native sawgrass (Cladium jamaicense). In order to study ecological management solutions in this area, WCA-2A was broken into study plots; several of which became open water areas through the application of herbicide and burning regimens. The open water areas …


Environmental Stressors: Pathways Of Exposure And Aquatic Invertebrate Response, Carly Jean Nowicki Jan 2014

Environmental Stressors: Pathways Of Exposure And Aquatic Invertebrate Response, Carly Jean Nowicki

Wayne State University Dissertations

The need to monitor freshwater and detect impairments prior to observable impacts is crucial to maintain species diversity and ecosystem function. Therefore, understanding the contribution of various matrices (i.e., sediment and water) to chemical exposure is critical for remediation of impacted sites.

To evaluate various matrices of chemical exposure, I focused on the organic pollutant polychlorinated biphenyls (PCBs) due to their relatively ubiquitous nature, high toxicity, and adverse effects on humans and wildlife. In complementary laboratory and field experiments, I compared the effects of aqueous versus sedimentary exposure of PCBs on invertebrates. In the laboratory, organisms exposed to PCB-contaminated sediments …