Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Life Sciences

Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi Jan 2018

Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi

Dissertations, Master's Theses and Master's Reports

Cladophora glomerata is a filamentous green alga native to the Great Lakes. However, its nuisance growth in phosphorus rich waters negatively affects the lakes’ aesthetic and water quality. The Great Lakes Cladophora Model (GLCM) v1, developed in 1982, was the first mechanistic model to simulate Cladophora growth basing phosphorus availability and environmental conditions followed by Cladophora Growth Model and GLCM v2. In this study, the light and temperature mediation factors for Cladophora net growth are revised as a necessary step prior to the development of a self-shading algorithm. The concept of a fixed-value, maximum achievable biomass (carrying capacity) employed in …


Intraspecific Genetic Variation, Population Structure, And Performance Of The Invasive Aquatic Macrophyte Eurasian Watermilfoil (Myriophyllum Spicatum) In Waterbodies With And Without Histories Of Chemical Herbicide Treatment Across Michigan, Taylor Zallek Jan 2018

Intraspecific Genetic Variation, Population Structure, And Performance Of The Invasive Aquatic Macrophyte Eurasian Watermilfoil (Myriophyllum Spicatum) In Waterbodies With And Without Histories Of Chemical Herbicide Treatment Across Michigan, Taylor Zallek

Dissertations, Master's Theses and Master's Reports

Populations of invasive species are often subjected to novel selective forces in the form of anthropogenic control agents in their introduced ranges. These control agents, applied unevenly among populations within a species’ new range, can send invasive populations on drastically different evolutionary and ecological trajectories. In these studies, we aimed to see if different histories of chemical herbicide treatment are differentially influencing the genetic diversity, structure, and performance of populations of invasive watermilfoil (Myriophyllum spicatum and M. spicatum x M. sibiricum hybrids) from waterbodies in the state of Michigan. We sampled ten waterbodies with different histories of herbicide treatment …


Microbial Community Response To Light And Heavy Crude Oil In Freshwater Systems, Timothy M. Butler Jan 2018

Microbial Community Response To Light And Heavy Crude Oil In Freshwater Systems, Timothy M. Butler

Dissertations, Master's Theses and Master's Reports

With increased demand for oil, there is an increased risk for oil spills in many environments. A number of pipelines transport oil near or across freshwater systems including the Great Lakes. Microbes are capable of breaking down oil and have thus been proposed as tools for oil spill response through bioremediation. There is a need to understand the microbial response to diverse oil types in freshwater environments due to the lack of research into this topic. This study’s main objectives are to understand how the freshwater microbial communities respond to oil, and how the bacterial communities may respond to different …


Ecological Implications Of Foraging And Life-History In Three Cold-Adapted Species, Andrew Von Duyke Jan 2018

Ecological Implications Of Foraging And Life-History In Three Cold-Adapted Species, Andrew Von Duyke

Dissertations, Master's Theses and Master's Reports

This research investigates the ecology of: ringed seals (Pusa hispida), moose (Alces alces), and bowhead whales (Balaena mysticetus). Each of these species draws upon specialized strategies to meet the physical demands of life in their extreme environments. However, they are currently experiencing unprecedented changes in their habitats. This work adds to what is known about the behavior, physiology, and population dynamics of cold-adapted species—providing insights of value for an improved understanding of foraging and life-history theory, and informing conservation and ecosystem monitoring efforts. Chapter 1 provides a brief introduction to the scope of work …


The Dynamic Nature Of Forage Preference And Microhistological Atlas, John J. Henderson Jan 2018

The Dynamic Nature Of Forage Preference And Microhistological Atlas, John J. Henderson

Dissertations, Master's Theses and Master's Reports

Moose, Alces alces, are among the most iconic species in the northern circumpolar temperate forests. Multiple factors influence moose density. Winter is a time of severe dietary stress for moose because deciduous trees are leafless and available forage is limited to conifers with high plant secondary metabolites or low-energy deciduous twigs. Forage preference depends on the intrinsic forage properties, abundance of forage and environmental stressors. These stressors include predation risk and severity of climate that affect forage efficiency. We examined forage preference of moose on Isle Royale National Park during winter over a ten-year period. Diet was divided into …