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Full-Text Articles in Life Sciences

Developing Rapid Indicators To Detect Micropollutants In Coastal Blackwater Rivers In South Carolina, Lydia Winn Dec 2023

Developing Rapid Indicators To Detect Micropollutants In Coastal Blackwater Rivers In South Carolina, Lydia Winn

All Theses

Micropollutants in water sources are found in higher concentrations in areas with high levels of urban and agricultural land. These pollutants can be introduced into water sources during storms and rain events, through water treatment outputs, and commercial or residential waste. These events increase the levels of both nutrients and micropollutants in these water sources. With increasing levels of micropollutants in rivers, this study’s goal was to develop an alternative detection method or an indicator test for the levels of micropollutants in water. We first proposed the use of amicrobial fuel cell (MFCs) operating as a biosensor could be utilized …


Short-Term Versus Long-Term Effects Of Nitrogen Addition And Warming On Ecosystem N Dynamics In A Grass-Dominated Temperate Old Field, Benjamin F. A. Souriol Oct 2023

Short-Term Versus Long-Term Effects Of Nitrogen Addition And Warming On Ecosystem N Dynamics In A Grass-Dominated Temperate Old Field, Benjamin F. A. Souriol

Electronic Thesis and Dissertation Repository

Increased atmospheric nitrogen (N) deposition and climate warming are both anticipated to influence the ecosystem N dynamics of northern temperate ecosystems substantially over the next century. Nevertheless, in field experiments with N addition and warming treatments, temporal scale can play an important role in determining the extent of treatment effects on N dynamics, and it is unclear to what extent the results of short-term studies can be extrapolated to responses over longer time scales. I compared the short-term versus long-term effects of N addition and warming on net N mineralization, N leaching, and N retention in a grass-dominated old field. …


Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample Aug 2023

Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample

Theses and Dissertations

Increasing wetland restoration in the Lower Mississippi Alluvial Valley has been identified as a method to reduce nutrient loading in the Gulf of Mexico. Wetlands have historically been used to treat water through processes facilitated by wetland plants, and relatively few species and plant traits have been identified as important in carrying out these processes. This study focuses on some of those species and traits and aims to identify species differences and plant traits that may be important for wetland nutrient mitigation. Chapter I provides background information on nutrient pollution, wetland biogeochemical mechanisms for nutrient sequestration, and the focal species …


Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle Aug 2023

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 …


Interactive Effects Of Bark Beetles, Ophiostomatoid Fungi, And Subterranean Termites On Wood Decomposition And The Biogeochemical Cycling Of Pine Forests, Kimberlyn Pace May 2023

Interactive Effects Of Bark Beetles, Ophiostomatoid Fungi, And Subterranean Termites On Wood Decomposition And The Biogeochemical Cycling Of Pine Forests, Kimberlyn Pace

Theses and Dissertations

A frequent source of pine tree mortality in recent years can be attributed to pine bark beetles and their vectored Ophiostomatoid fungi, an organism that has been observed to attract subterranean termites that preferentially recruit to this downed woody debris. This interaction may significantly modify biogeochemical fluxes in bark beetle mass mortality events, but studies are often limited to singular regions or single pine-dominated ecosystems. Two studies were designed to test the interactive effects of these associations on terrestrial biogeochemical cycles and decomposition processes, the first using replicated field trials in Mississippi, Arizona, and Honduras across two years and the …


The Impacts Of Seasonality And Nutrient Loading On Microcystis Bloom Development In Wall Pond, Alyssa Antolak May 2023

The Impacts Of Seasonality And Nutrient Loading On Microcystis Bloom Development In Wall Pond, Alyssa Antolak

Honors Theses

The harmful cyanobacteria Microcystis globally dominates eutrophic freshwater systems. Eutrophication leading to nitrogen and phosphorus loading into aquatic systems is increasing bloom propagation and shifting diatom/dinoflagellate dominated systems to cyanobacteria dominated systems. Understanding seasonal variability and environmental parameters combined with nutrient loading will allow for a better understanding of what factors are influencing Microcystis blooms. Biweekly plankton samples and environmental parameters were collected from Wall Pond from spring 2022-spring 2023. Results show that yearly plankton samples shifted from Microcystis dominated in the early summer to diatom dominated in the late summer-early fall then back to Microcystis dominated in late fall-early …


Increasing Productivity And Biodiversity Of Tall Fescue Swards By Intercropping Cool And Warm-Season Forage Species, Michael Dereck Corbin May 2023

Increasing Productivity And Biodiversity Of Tall Fescue Swards By Intercropping Cool And Warm-Season Forage Species, Michael Dereck Corbin

Doctoral Dissertations

Mixed pastures are known to produce greater biomass yields and higher nutritive value than monocultures. Intercropping biologically N fixating legumes, along with the use of intercropping warm-season annual grasses, such as crabgrass [Digitaria ciliaris Retz.], provides the potential to aid tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] productivity. To determine the benefits of intercropping species into tall fescue forage systems in the Southeastern U.S., two studies were developed. The first study consisted of 9 tall fescue paddocks, in which 3 paddocks contained red clover (Trifolium pratense L. [TRC]) mixed with tall fescue, 3 paddocks contained sunn …


Near-Surface Soil Nitrogen And Vegetation Response To Invasive Emerald Ash Borer In Forested Black Ash Wetlands Of The Western Upper Peninsula, Michigan, Usa, Daniel A. Beyer Jan 2023

Near-Surface Soil Nitrogen And Vegetation Response To Invasive Emerald Ash Borer In Forested Black Ash Wetlands Of The Western Upper Peninsula, Michigan, Usa, Daniel A. Beyer

Dissertations, Master's Theses and Master's Reports

Invasive emerald ash borer (EAB) (Agrilus planipennis Fairmaire) poses an imminent threat to the structure and function of North American hardwood forests, particularly black ash (Fraxinus nigra Marshall), and alters the hydrologic and ecological services of their wetlands. Black ash trees regularly grow in seasonally saturated soils and are responsible for hydrologic regulation and nutrient cycling. In this study, a gradient of black ash wetlands impacted by EAB were monitored to assess vegetation changes and near-surface soil nitrogen availability. Vegetation community changes were intertwined with nitrogen cycle disturbances following EAB infestation. As black ash died and fell to …


Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor Jan 2023

Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor

Cal Poly Humboldt theses and projects

This thesis addressed two challenging aspects of microplastic research, including the quantification of microplastics in organic-rich water, and the investigation of how microplastics impact microorganisms and related nutrient-cycling. Two projects were designed and executed to address specific research objectives relating to these broad topics. The first objective was to develop and implement methods to determine the effectiveness of microplastic removal across the natural treatment systems at the Arcata Wastewater Treatment Facility (AWTF). The second objective was to observe how microplastics found in domestic wastewater impact the bacterial communities and nitrogen cycling in freshwater treatment wetland sediment through a bench-scale experiment, …