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Articles 1 - 30 of 44
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Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample
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
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 …
An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew
Theses and Dissertations
Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …
Utilization Of A Boosted Regression Tree Framework For Prediction Of Dissolved Phosphorus Concentrations Throughout The High Plains Aquifer Region, Jeffrey M. Temple
Utilization Of A Boosted Regression Tree Framework For Prediction Of Dissolved Phosphorus Concentrations Throughout The High Plains Aquifer Region, Jeffrey M. Temple
Theses and Dissertations
Groundwater-derived phosphorus has often been dismissed as a significant contributor towards surface water eutrophication, however, this dismissal is unwarranted, making the quantification of phosphorus concentrations in groundwater systems immensely important. Machine learning models have been employed to quantify the concentrations of various contaminants in groundwater, but to our best knowledge have never been used for the quantification of groundwater phosphorus. The goal of this research was to use a boosted regression tree framework to produce the first believed machine learning model of phosphorus variability in groundwater, with the High Plains aquifer serving as the study area. Results display a boosted …
Climate Change And The Global Nutrient Overload: The Microbial Response Of Extreme Waterbodies To Environmental Change, Samuel P. Bratsman
Climate Change And The Global Nutrient Overload: The Microbial Response Of Extreme Waterbodies To Environmental Change, Samuel P. Bratsman
Theses and Dissertations
One of the defining characteristics of our current epoch—the Anthropocene—is modification of nutrient cycles. At regional to global scales, humans have fundamentally reshaped the availability of carbon, nitrogen, and phosphorus. These changes are particularly apparent in freshwater ecosystems, which receive surface and groundwater inputs of nutrients from agriculture, fossil fuel use, and wastewater. In this thesis, I investigated how the addition of nutrients affects microbial community and biogeochemistry in two extreme environments: the hypereutrophic shallow Utah Lake and nutrient-limited Arctic permafrost streams. In my first chapter, I used bioassay and dilution bioassay experiments to identify what factors control harmful algal …
Improving Water Quality Through Reducing Agricultural Nutrient Loss: Field Pennycress As A Cover Crop, Mujen Wang
Improving Water Quality Through Reducing Agricultural Nutrient Loss: Field Pennycress As A Cover Crop, Mujen Wang
Theses and Dissertations
Agricultural nutrient loss through water runoff from the Upper Mississippi (UM) River Basin is one of the major contributing sources to the Gulf of Mexico hypoxic dead zone. Cover cropping has been identified as one strategy for farmers to use to reduce nutrient loss from their fields. However, the upfront costs and slow economic return of implementing cover crops prevent farmers from widely adopting traditional cover crops.Field pennycress (Thlaspi arvense) is an emerging potential “cash cover crop” species that may provide the soil and environmental benefits of traditional cover crops and the economic incentive farmers need to widely implement cover …
Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee
Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee
Theses and Dissertations
Bioavailable phosphorus loads exported to Lake Michigan from the Milwaukee and Sheboygan River Watersheds appear to have increased in the last 40 years despite meeting total phosphorus (TP) loading goals set by the Great Lakes Water Quality Agreement (GLWQA).Overall, bioavailability of P delivered from the Milwaukee and Sheboygan Rivers was highest during the warmer months, which coincides with the nearshore nuisance algae growth season. However, first order loss rates of SRP calculated during baseflow recession were also greatest during the summer, suggesting that increased river residence time during the summer could reduce export of bioavailable P. Observations of phosphorus partitioning …
Total Suspended Sediment And Phosphorus Transport In Response To Storm Events In An Agriculturally Dominated Watershed, Elijah John William Schukow
Total Suspended Sediment And Phosphorus Transport In Response To Storm Events In An Agriculturally Dominated Watershed, Elijah John William Schukow
Theses and Dissertations
Increased sediment introduction and transport in streams negatively impact water quality. Deleterious effects include reservoir filling, water pollution and ecological impairment. Sediment introduction and transport typically takes place during storm events. Phosphorus introduction, generally from loss of agricultural runoff and soil erosion also typically takes place during storm events. When phosphorus is applied for agricultural uses it is preferentially retained by smaller sediments. During storm events, these phosphorus rich sediments are more likely to enter the stream system. A small number of large storms can account for a large percentage of sediment and total phosphorus introduction, leading to elevated levels …
Quagga Mussel Induced Phosphorus Cycling Changes In Lake Michigan, Rae-Ann Maclellan-Hurd
Quagga Mussel Induced Phosphorus Cycling Changes In Lake Michigan, Rae-Ann Maclellan-Hurd
Theses and Dissertations
Quagga mussels (Dreissena rostriformis bugensis) are an invasive ecosystem engineer that have successfully colonized both profundal and nearshore regions in Southern Lake Michigan. Quagga mussels directly altered the flow of nutrients by filtering particles, excretion of soluble forms of nutrients in the benthos, and through the production of biodeposits. Mussel excretion, egestion, and capture rates of P were compared between a 25 meter and a 55 meter deep site near Milwaukee Harbor to determine the retention of nutrients in these regions. The capture rate of particulate phosphorus at the 25m site (278 ± 388 μmol m-2) was similar to that …
A Study Of The Anthropogenic Impact In Farmington Bay Through Isotopic And Elemental Analysis, Nathan Vaun Gunnell
A Study Of The Anthropogenic Impact In Farmington Bay Through Isotopic And Elemental Analysis, Nathan Vaun Gunnell
Theses and Dissertations
The influence of human activity on surrounding environments is an important field of research. With respect to aquatic settings, lacustrine deposits provide excellent proxies of environmental change since the sediment accumulates at a relatively constant rate, recording environmental change. This study employs isotopic, mineral, and chemical records from Farmington Bay freeze cores, in particular δ13C, δ15N, and 210Pb isotopes as well as phosphorus level fluctuation and trace metal analysis. In particular, 210Pb isotopes permit estimation of the age of sediment with depth and δ15N, δ13C, and concentration of P provides a record of changing nutrient sources and level of eutrophication. …
Nutrient Limitation Of Phytoplankton In Lake Wateree, South Carolina: Implications For Future Water Quality Management, Kara M. Clyburn
Nutrient Limitation Of Phytoplankton In Lake Wateree, South Carolina: Implications For Future Water Quality Management, Kara M. Clyburn
Theses and Dissertations
Cultural eutrophication is a primary contributor to phytoplankton production in freshwater lakes from excess anthropogenic nutrient inputs, and resulting impacts on water quality, aquatic ecosystems, human and animal health are increasing worldwide. Understanding the factors that limit phytoplankton growth is an important strategy for identifying and managing nutrient sources and successfully controlling the over- enrichment of nitrogen (N) and/or phosphorus (P) in freshwater lakes. The Redfield molecular ratio of carbon (C), N and P maintains that the C:N:P molar ratio is 106:16:1 when nutrients are not limiting, and the ecosystem is balanced. A N:P molar ratio > 20:1 tends to be …
Nitrogen And Phosphorus Uptake In An Urban Stream Ecosystem, Nicolette A. Sheffield
Nitrogen And Phosphorus Uptake In An Urban Stream Ecosystem, Nicolette A. Sheffield
Theses and Dissertations
Urban stream ecosystems are faced with high input levels of nitrogen (N) and phosphorus (P) from anthropogenic activities. N and P are important to plant growth and stream health; however, high levels can lead to algal blooms and eutrophication, a harmful effect to both aquatic life and water quality. Common urban sources of N and P include fertilizer, atmospheric deposition, stormwater outfall, and leaf-litter decomposition. Common urban stream features such as a flashier hydrograph, altered channel stability and morphology, increase in nutrient output (such as N and P), and heat retention, have been shown to result in an overall decrease …
Measuring And Calculating Current Atmospheric Phosphorous And Nitrogen Loadings On Utah Lake Using Field Samples, Laboratory Methods, And Statistical Analysis: Implication For Water Quality Issues, Jacob Milton Olsen
Theses and Dissertations
Atmospheric nutrient loading and transport though precipitation and dry deposition is one of the least understood yet one of the most important pathways of nutrient transport into many lakes. These nutrients, phosphorus and nitrogen, are essential for aquatic life and often play major roles in algae blooms that occur in lakes and reservoirs. Often heavy algal growth intensifies a variety of water quality problems. Utah Lake may be even more susceptible to atmospheric deposition due to its large surface area to volume ratio and proximity to Great Basin dust sources. In this study, eight months of atmospheric deposition data were …
Evaluating The Evidence And Assessing Registered Dietitian Nutritionists' Perceptions Of The Complex Renal Dietary Restrictions, Alyssa Lee Welte
Evaluating The Evidence And Assessing Registered Dietitian Nutritionists' Perceptions Of The Complex Renal Dietary Restrictions, Alyssa Lee Welte
Theses and Dissertations
The renal diet is often regarded as challenging to teach and follow, and can easily lead to additional complications, including malnutrition. Recent trends in the literature have suggested a liberalization in the renal diet, though no studies have assessed whether Registered Dietitian Nutritionists (RDNs) are comfortable making this change. An original, cross-sectional survey was created for this study. 187 renal dietitians completed the survey which revealed that only 15.3% of participants felt it is acceptable to liberalize the standard dietary restriction on fruits and vegetables, and 13.6% said the same about the bean and legume restriction. 19.9% are extremely likely …
Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose
Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose
Theses and Dissertations
The median total dissolved phosphorus concentration (0.41 mg/L P) of groundwater from the Mississippi River Valley alluvial aquifer exceeded the U.S. Environmental Protection Agency’s stream nutrient criteria (of 0.1 mg/L P) and the national background for phosphorus in groundwater (0.02 mg/L P). A general association between elevated phosphorus and dissolved iron concentrations suggests that reducing conditions that mobilize iron in the aquifer also may facilitate transport of phosphorus. These elevated concentrations of phosphorus may indicate phosphorus in the study area may be concentrated through irrigation return flow and groundwater discharge, and may contribute to the Gulf of Mexico hypoxic zone. …
Assessing Phosphorus Sources With A Gis-Based Phosphorus Risk Index In A Mixed-Use, Montane Watershed, Josiah A. Johns
Assessing Phosphorus Sources With A Gis-Based Phosphorus Risk Index In A Mixed-Use, Montane Watershed, Josiah A. Johns
Theses and Dissertations
Elevated phosphorus (P) loading of freshwater lakes and reservoirs often results in poor water quality and negative ecological effects. Critical source areas (CSA) of P in the watershed can be difficult to identify and control. A useful concept for identification of a CSA is the P risk index (P Index) that evaluates the P risk associated with distinct source and transport pathways. The objectives of this study were to create a GIS model that adapts the Minnesota (MN) P Index for use at the watershed scale in a mixed-use, mountain environment, and to evaluate its effectiveness relative to field-based assessment. …
Assessing Phosphorus Sources With Synoptic Sampling In The Surface Waters Of A Mixed-Use, Montane Watershed, Austin Willis Pearce
Assessing Phosphorus Sources With Synoptic Sampling In The Surface Waters Of A Mixed-Use, Montane Watershed, Austin Willis Pearce
Theses and Dissertations
Few elements in surface waters are monitored as closely as phosphorus (P) due to its role in the eutrophication and degradation of surface waters. Limiting P mobilization from source areas is, therefore, a central goal of water quality protection plans. But the work of locating sources in mixed-use watersheds is challenged by the spatial and temporal variability of critical source areas (CSAs) of P. Synoptic sampling is a proven method for capturing the spatial variation of water quality parameters in surface waters, though it's not often used to track temporal dynamics across the same study area. Phosphorus fractionation is an …
Nutrient Loading Reduction In A Tile Drained Agricultural Watershed Through Watershed-Scale Cover Cropping: A High Resolution Analysis, Benjamin Gerald Bruening
Nutrient Loading Reduction In A Tile Drained Agricultural Watershed Through Watershed-Scale Cover Cropping: A High Resolution Analysis, Benjamin Gerald Bruening
Theses and Dissertations
Nutrient pollution originating from agricultural regions in the Midwest is a serious issue, leading to pollution of drinking water sources as well as large hypoxic zones in the Gulf of Mexico. The source of much of this contamination has been shown to be runoff from agricultural fields in the Upper Mississippi River Basin. One method that has been shown to reduce this pollution from the Upper Mississippi River Basin is the planting of winter cover crops. Winter cover crops such as rye and tillage radish have been shown to significantly reduce nitrate exported from agricultural fields, even in tile-drained watersheds …
Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo
Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo
Theses and Dissertations
Nutrients such as nitrate and phosphorus are necessary for life, but excessive amounts can be detrimental. Large amounts of nutrients entering bodies of water can lead to hypoxic zones such as the one in the Gulf of Mexico. Nutrients are also problematic in drinking water reservoirs, as high concentrations of nitrate in drinking water can cause health conditions such as blue baby syndrome and high phosphorus concentrations can lead to algal blooms. Suspended sediment leads to reservoir sedimentation, habitat degradation, and is able to transport particulate nutrients. High nutrient and sediment concentrations are a recurring problem in the drinking water …
Marine Phosphorus Biogeochemistry Ecological Insights From Analytical Chemistry, Douglas W. Bell
Marine Phosphorus Biogeochemistry Ecological Insights From Analytical Chemistry, Douglas W. Bell
Theses and Dissertations
The supply of phosphorus (P) directly impacts the growth and speciation of marine microbes (i.e., phytoplankton, bacteria, Archaea). In turn, microbial communities shape the magnitude and rate of marine biogeochemical cycles, ultimately affecting global climate and food production. This dynamic reflects the continuum of temporal and spatial scales at which the marine P cycle operates. However, linking multiple scales of cycling remains a consistent challenge. The primary objective of my dissertation was to gain insight into marine P biogeochemistry, by means of analytical chemistry, at the molecular and environmental scales of cycling. The first component of my research was to …
The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck
The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck
Theses and Dissertations
Wastewater application to land can be a useful tool for mitigating impacts of nutrient enrichment on aquatic systems. A land application treatment system at VCU’s Rice Rivers Center in Charles City County, VA provided an opportunity to study the impact of wastewater addition on the biogeochemistry of forests representative of the Mid-Atlantic Coastal Plain. Nutrient concentrations in throughfall and leachate were measured at Treatment and Control sites to assess differences in nutrient deposition and retention. Wastewater amended plots from the Walter L. Rice education building received 20-fold (N) and 6-fold (P) higher inputs relative to Control plots and plots located …
Effect Of Cover Crops And Nitrogen Application Timing On Nutrient Loading And Concentration Through Subsurface Tile Drainage, Michael Douglas Ruffatti
Effect Of Cover Crops And Nitrogen Application Timing On Nutrient Loading And Concentration Through Subsurface Tile Drainage, Michael Douglas Ruffatti
Theses and Dissertations
It has been estimated that nitrate (NO3-N) leaching from artificially drained agricultural fields in the Upper Mississippi River Basin accounts for approximately 65% of nitrogen (N) delivered annually to the Gulf of Mexico. Therefore, the objectives of this study were to investigate the impact fertilizer application timing and cover crops (CC) adoption on the load and concentration of nutrients in subsurface drainage leachate. This experiment was conducted at the Illinois State University Nitrogen Management Field Station, in Lexington, IL. Treatments include a zero control (no N fertilizer and no cover crop), fall dominated N application (70% fall, 30% spring) with …
Seasonal And Spatial Variations In Chemical Composition And Fluxes Of Dissolved Organic Matter And Nutrients In The Lower Milwaukee River, Tarek A. Teber
Seasonal And Spatial Variations In Chemical Composition And Fluxes Of Dissolved Organic Matter And Nutrients In The Lower Milwaukee River, Tarek A. Teber
Theses and Dissertations
Physical, chemical and biological processes directly influence the transport, composition, and fluxes of dissolved organic matter (DOM) in river watersheds. Changes in the abundance and composition of DOM and nutrients (P&N) in the watershed should reflect changes in hydrological cycle, effluent discharge, land-use and land-cover, and anthropogenic activities in the river basin, especially in rivers that run through metropolitan areas such as the Milwaukee River. Despite the importance of DOM to ecosystem health and function, a literature search to date finds no comprehensive accounting of DOM in the Milwaukee River. To examine DOM dynamics, monthly water samples were collected between …
Deficient, Adequate And Excess Nitrogen, Phosphorus, And Potassium Growth Curves Established In Hydroponics For Biotic And Abiotic Stress-Interaction Studies In Lettuce, Douglas Keith Jacobson
Deficient, Adequate And Excess Nitrogen, Phosphorus, And Potassium Growth Curves Established In Hydroponics For Biotic And Abiotic Stress-Interaction Studies In Lettuce, Douglas Keith Jacobson
Theses and Dissertations
Mineral nutrients have marked effects on plant health by providing the building blocks for plant growth, as well as for mitigating abiotic and biotic stress factors, particularly disease development. Even if mineral nutrition field studies are conducted to study pest management, they are at the mercy of complex soil, water, and climatic conditions not amenable to strict experimental control. Therefore, a hydroponic method of growing lettuce was developed and growth curves were established for the macronutrients nitrogen (N), phosphorus (P), and potassium (K). Lettuce plants were grown at varying levels of each nutrient: 2.5, 5, 10, 20, 40, 80, 160, …
Modeling Lake Michigan Nearshore Carbon And Phosphorus Dynamics, Joseph Henry Fillingham
Modeling Lake Michigan Nearshore Carbon And Phosphorus Dynamics, Joseph Henry Fillingham
Theses and Dissertations
Dreissenid mussels, in particular quagga mussels (Dreissena rostiformis bugensis), are transforming the Lake Michigan ecosystem by clearing the water column, recycling phosphorus and modifying benthic habitat. These impacts are thought to have caused observed declines in the spring phytoplankton bloom in Lake Michigan, as well as changes to food web structure and declines in the abundance of critical invertebrate and fish species. In the nearshore zone, the resurgence of benthic Cladophora algae to nuisance levels not observed since phosphorus loading abatement policies instituted in the 1970s has also been attributed to water column clearing and phosphorus recycling by mussels. Using …
Evaluation Of Sediment And Nutrient Loss During The Revegetation Of Mississippi Roadsides, Kyle R. Briscoe
Evaluation Of Sediment And Nutrient Loss During The Revegetation Of Mississippi Roadsides, Kyle R. Briscoe
Theses and Dissertations
Runoff during the revegetation of roadsides can transport sediment and nutrients offsite, leading to surface water quality reductions. Two field experiments were conducted near Starkville, MS in 2011 and 2012 to evaluate the influence of N and P sources and rates, fertilization timing, and mulch type on vegetative establishment and nutrient and sediment runoff losses. Stainless steel runoff frames (0.75 x 2.0 m) were installed on 10% and 15% slopes for Experiment I and Experiment II, respectively. A bahiagrass (Paspalum notatum Flugge), tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.], sericea lespedeza [Lespedeza cuneata (Dum. Cours.) G. Don], and common …
Importance Of Placement Depth In Evaluating Soil Nitrogen, Phosphorus, And Sulfur Using Ion Exchange Resin Capsules In Semi-Arid, Low Fertility Soils, Rachel Lynn Buck
Importance Of Placement Depth In Evaluating Soil Nitrogen, Phosphorus, And Sulfur Using Ion Exchange Resin Capsules In Semi-Arid, Low Fertility Soils, Rachel Lynn Buck
Theses and Dissertations
Ion exchange resin capsules provide a possible alternative to conventional soil testing procedures. Previous studies with semi-arid, low fertility soils observed poor relationships with poorly mobile nutrients such as phosphorus (P). We propose that placement depth may improve those relationships. Our objective was to (1) determine if placement depth could improve resin capsule estimation of the bioavailability of nitrogen (N), P, and sulfur (S) and (2) to determine if resin capsules can effectively estimate S availability in semi-arid, low fertility soils. Field sites were established in Rush and Skull Valleys, Utah on loam and sandy loam soils, respectively. Fertilizer was …
Hypersaline Lake Environments Exhibit Reduced Microbial Dormancy, Joshua Christopher Vert
Hypersaline Lake Environments Exhibit Reduced Microbial Dormancy, Joshua Christopher Vert
Theses and Dissertations
From acid seeps and deep-sea thermal vents to glacial ice and hypersaline lakes, extreme environments contain relatively simplified communities consisting of extremophiles that have evolved to survive and thrive under adverse abiotic conditions. In more neutral environments, microorganisms use dormancy as a common life history strategy to weather temporal fluctuations of resources or stresses until more 'optimal' conditions are present. It is unclear if dormancy is an essential survival mechanism for microorganisms in extreme environments; however, recent studies suggest that extreme environments may create stable conditions for extremophiles to the extent that dormancy is of less ecological importance. Using lake …
Microbial Responses To Coarse Woody Debris In Juniperus And Pinus Woodlands, Deborah Monique Rigby
Microbial Responses To Coarse Woody Debris In Juniperus And Pinus Woodlands, Deborah Monique Rigby
Theses and Dissertations
The ecological significance of coarse woody debris (CWD) is usually highlighted in forests where CWD constitutes much of an ecosystem's carbon (C) source and stores. However, a unique addition of CWD is occurring in semi-deserts for which there is no ecological analog. To stem catastrophic wildfires and create firebreaks, whole Juniperus osteosperma (Torr.) and Pinus edulis (Engelm.) trees are being mechanically shredded into CWD fragments and deposited on soils previously exposed to decades of tree-induced changes that encourage "tree islands of fertility." To investigate consequences of CWD on C and nitrogen (N) cycling, we evaluated microbial metabolic activity and N …
Pond Management Approaches And Effects On Trophic Dynamics, Michael Scott Sherman
Pond Management Approaches And Effects On Trophic Dynamics, Michael Scott Sherman
Theses and Dissertations
Mississippi has an abundance of ponds which provides a number of opportunities for anglers. Several enhancement strategies are used to improve fish production in ponds, including fertilizing and supplemental feeding. These strategies may ignore the potential ecological impacts that may unexpectedly arise, such as prolific plant growth. This study consists of two phases; first, a mesocosm experiment investigating fertilizer application rates (mg P/L) in relation to potential sunfish growth, and second, a replicated pond experiment consisting of four treatments to simulate commonly used enhancement strategies. Mesocosm experiment showed a peak of sunfish growth at the 0.6 mg P/L level and …