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- Keyword
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- Lake Michigan (3)
- Ecology (2)
- Freshwater (2)
- Alewife (1)
- Aquaculture (1)
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- Aquaponics (1)
- Behavior (1)
- Benthic (1)
- Biogeochemistry (1)
- Biosolids (1)
- CHEMTAX (1)
- Chlorophyll A (1)
- Contaminants of emerging concern (1)
- Copepods (1)
- Data fusion (1)
- Dissolved organic matter (1)
- Dredging (1)
- Dreissenids (1)
- Estrogenicity (1)
- Eutrophication (1)
- FIA (1)
- Flow field-flow fractionation (1)
- Food Web (1)
- Food Webs (1)
- Gene Expression (1)
- HPLC (1)
- Hemimysis (1)
- Hydroponics (1)
- Methylmercury (1)
- Molecular weight (1)
Articles 1 - 12 of 12
Full-Text Articles in Physical Sciences and Mathematics
Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle
Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle
Theses and Dissertations
This study examined the nutrient environment of sediments in the Milwaukee River estuary and the dynamics of those nutrients during simulated disturbance experiments within the context of large-scale dredging remediation. Surface sediments were collected from throughout the Milwaukee estuary (including river, harbor, and nearshore stations) by PONAR, centrifuged to separate porewater (interstitial water) from solid material, and filtered to further isolate and stabilize dissolved material. Porewaters were analyzed for dissolved nutrients including ammoniacal nitrogen (AN), nitrate, nitrite, and soluble reactive phosphorus (SRP). Surface sediment porewaters within the estuary were often highly enriched in AN and SRP, which were often 10-2000x …
Transcriptomics And Toxcast Data Identify Bioeffects In Zebrafish Embryos Exposed To Chemical Mixtures In An Effluent-Dominated Stream, Emma Meade
Theses and Dissertations
Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic organisms but also continually expose them to complex mixtures of pharmaceuticals and other contaminants of emerging concern (CECs) that can potentially impair growth, behavior, and reproduction. Limited toxicity data on the adverse biological impacts of in vivo exposure to these mixtures make it difficult to assess risk for aquatic organisms, particularly with respect to pharmaceuticals whose designed bioactivity often extends beyond conventionally monitored biological pathways. To address this knowledge gap, the goal of this thesis was to identify biomarkers of exposure to complex CEC mixtures relevant to specific chemicals …
Molecular Weight Distributions And Size-Dependent Composition Of Dissolved Organic Matter In The Aquatic Continuum, Hui Lin
Theses and Dissertations
Dissolved organic matter (DOM) in aquatic environments is one of the most important carbon reservoirs in global carbon cycling. The molecular weight of DOM is strongly related to a great number of biogeochemical reactions, influencing ecological functions and the fate of bioactive elements in aquatic ecosystems. A new technique coupling flow field-flow fractionation with fluorescence excitation-emission matrix (EEM) and parallel factor (PARAFAC) analysis was developed to elucidate the variations in DOM composition and optical properties with molecular weight in the individual samples and their changes along the aquatic continuum. Based on the novel coupling technique, variations in DOM characteristics were …
Health Goals For Perfluorinated Alkyl Substances (Pfas): A Review Of Branched Isomers, The Role Of Industrial Sources, And The Implications Of Pfas In Biosolids On End-Of-Life Disposal Methods, Katarina Schulz
Theses and Dissertations
Per- and polyfluorinated alkyl substances, or PFAS, have been used for over half a century, but have become an emerging contaminant of significant concern due to their newly found widespread occurrence and recalcitrance in the environment, their tendency to bioaccumulate, and the health effects now associated with a very low level of exposure. Many gaps in knowledge remain about the fate of these chemicals in the environment and the extent of their impacts on biota. This thesis aims to fill some of the recognized gaps in knowledge: differences between linear and branched isomers of PFAS, predicting the presence of PFAS …
Analysis Of Plant Biomass Production Comparing Decoupled Aquaponics Against Equivalent Single-Loop Aquaponic And Hydroponic Systems Growing Lactuca Sativa, Haley Luise Lucas
Analysis Of Plant Biomass Production Comparing Decoupled Aquaponics Against Equivalent Single-Loop Aquaponic And Hydroponic Systems Growing Lactuca Sativa, Haley Luise Lucas
Theses and Dissertations
Aquaponics is an emerging method of agriculture in which fish and plants are grown in an enclosed and recirculating environment. The method mimics a relationship found in nature where fish waste provides nutrients for plants and plants cleanse the water for the benefit of the fish. This symbiotic relationship has proven to be a sustainable method of agriculture in which there is less water use, no need for pesticides or herbicides, recycling of nutrient waste and a smaller spatial footprint. However, the production of both plants and fish in a recirculating aquaponics system has produced less yield and profit when …
A Hemimysis Driven Novel Ecosystem At A Modified Boulder Breakwall, Eric John Geisthardt
A Hemimysis Driven Novel Ecosystem At A Modified Boulder Breakwall, Eric John Geisthardt
Theses and Dissertations
The US Army Corps of Engineers (USACE) is mandated to maintain and repair aging breakwall structures in all commercial ports on the Great Lakes. In May of 2014, the construction of Milwaukee Harbor USACE “green” breakwall (GBW) reconciliation created complex rocky aquatic habitat by depositing cobble-sized stone as a veneer over standard 6-10 ton boulders, thus creating “control” (boulder) and “treatment” (cobble) habitats. The breakwall is home to a prolific population of Hemimysis anomala, the introduced Ponto-Caspian mysid, which is significantly more abundant on cobble versus boulders (p<0.05, using a novel trap for Hemimysis). Fish and forage communities were sampled in 2015 and 2016 using a combination of experimental and micromesh gill nets, night scuba diving surveys, and a novel Hemimysis trap. This nearshore lithophilic mysid appears to provide a significant new seasonal food resource in the Milwaukee Harbor for pelagic prey fishes during inshore spawning migrations and upwelling events. Alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax) fed heavily on Hemimysis with some individuals consuming hundreds of mysids. Night scuba diving surveys and gill netting confirmed that rainbow smelt preferred to forage on the cobble section (p<0.05), and also consumed more Hemimysis there than they did at the control breakwall site (p<0.05). Hemimysis were also the primary food item consumed by nearshore game fishes such as YOY yellow perch (Perca flavescens), YOY largemouth bass (Micropterus salmoides), and juvenile rock bass (Ambloplites rupestris) caught at the breakwall. This study provides the first documented evidence that where abundant in the Laurentian Great Lakes, Hemimysis do have the ability to significantly impact local food webs and drive the feeding ecology of both pelagic transient and nearshore resident fishes.
Development Of An Automated Detection System For Nitrite In Aquatic Environments, Tim Schierenbeck
Development Of An Automated Detection System For Nitrite In Aquatic Environments, Tim Schierenbeck
Theses and Dissertations
The main objective of the project is to develop an automated nitrite sensor for use in aquatic environments, and more specifically for use in recirculating aquaculture systems (RAS), where monitoring can help sustain a controlled environment, protect against nitrite intoxication, and promote fish health. Detecting nitrite manually with semi-quantitative colorimetric test kits, although inexpensive and simple, is prone to inter-user variability and poor sensitivity. An automated nitrite sensor has potential to provide higher resolution measurements at both concentration and time scales and can serve as a research tool for the study of filtration systems essential in maintaining a healthy RAS …
Neurobehavioral And Gene Expression Effects Of Early Embryonic Methylmercury Exposure In Yellow Perch (Perca Flavescens) And Zebrafish (Danio Rerio) Larvae, Francisco Xavier Mora Zamorano
Neurobehavioral And Gene Expression Effects Of Early Embryonic Methylmercury Exposure In Yellow Perch (Perca Flavescens) And Zebrafish (Danio Rerio) Larvae, Francisco Xavier Mora Zamorano
Theses and Dissertations
Methylmercury (MeHg) is a pervasive and persistent neurotoxic environmental pollutant known to affect the behavior of fish, birds and mammals. The present study addresses the neurobehavioral and gene expression effects of MeHg in yellow perch (Perca flavescens) and zebrafish (Danio rerio) embryos. The rationale for this study originated from an interest to understand the behavioral and molecular phenotypes of environmental MeHg exposure in the yellow perch, an ecologically and economically relevant species of the North American Great Lakes region. Both MeHg and the yellow perch coexist in a common ecosystem: the North American Great Lakes. However, the effects of this …
Phosphorus Recycling By Profunda Quagga Mussels In Lake Michigan, Caroline Mosley
Phosphorus Recycling By Profunda Quagga Mussels In Lake Michigan, Caroline Mosley
Theses and Dissertations
Quagga mussels (Dreissena rostiformis bugensis) act as ecosystem engineers in the southern basin of Lake Michigan, altering physical habitats and biogeochemical processes. Adapted to cold and oligotrophic conditions, profunda quagga mussels thrive on the soft substrate of deeper depths. At a 55 m site (10,000 mussels m-2) offshore from Milwaukee, WI, profunda mussel biomass (g m-2) was 1/3 of biomass (g m-2) measured at a 10 m comparison site (5,000 mussels m-2). Higher densities but less biomass is due to profunda mussels having less tissue for a given length and the population per m2 comprising of mostly small mussels ( …
Plankton Trophic Structure Within Lake Michigan As Revealed By Stable Carbon And Nitrogen Isotopes, Zachery G. Driscoll
Plankton Trophic Structure Within Lake Michigan As Revealed By Stable Carbon And Nitrogen Isotopes, Zachery G. Driscoll
Theses and Dissertations
Zooplankton represent a critical component of aquatic food webs in that they transfer energy from primary producers to higher trophic positions. However, their small size makes the application of traditional trophic ecology techniques difficult. Fortunately, novel techniques have been developed that can be used to elucidate feeding information between zooplankton species. I used the analysis of stable carbon and nitrogen isotope ratios to estimate the trophic structure of Lake Michigan's zooplankton community. The major zooplankton species, three size classes of seston, and seston from specific water column depths were collected in 2011 and 2012 for stable isotope analysis. Trophic position …
Nearshore Benthic Oxygen Dynamics In Lake Michigan, Emily H. Tyner
Nearshore Benthic Oxygen Dynamics In Lake Michigan, Emily H. Tyner
Theses and Dissertations
The intense colonization of the Laurentian Great Lakes by dreissenid mussels has profoundly changed ecosystem processes, particularly benthic oxygen dynamics. Dissolved oxygen concentrations in mussel beds, sloughed Cladophora mats, and sediment indicate that hypoxia forms and disappears in some substrata (ephemeral Cladophora mats), while occurring consistently in others (depositional areas of sloughed Cladophora). Dissolved organic carbon concentrations are high (mean: 143 ± ± 28 ppm) in depositional Cladophora mats but lower (˂ 10 ppm) in most other environments. Field sampling and laboratory experiments suggest that under conditions of low water velocity and thick Cladophora cover, hypoxia may develop atop …
Freshwater Phytoplankton Populations Detected Using High Pressure Liquid Chromatography (Hplc) Of Taxon-Specific Pigments, Lauren Jeanne Simmons
Freshwater Phytoplankton Populations Detected Using High Pressure Liquid Chromatography (Hplc) Of Taxon-Specific Pigments, Lauren Jeanne Simmons
Theses and Dissertations
Phytoplankton are key primary producers in aquatic ecosystems, and the principle food source for primary consumers. Individual phytoplankton species respond to different physical, chemical and biological parameters, so monitoring taxonomic composition of the phytoplankton community is a means to monitor changes in environmental conditions. Phytoplankton community changes have frequently been monitored by estimating biomass (using chlorophyll a, measured fluorometrically), and taxonomic data obtained from cell counts. While such methods are useful, they are time-consuming. I hypothesized that high pressure liquid chromatography (HPLC) methods, which have been frequently used in marine systems, would allow separation and identification of key pigments. …