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Articles 31 - 60 of 70
Full-Text Articles in Biogeochemistry
An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan
An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan
Mathematics, Physics, and Computer Science Faculty Articles and Research
This study considers the various factors that regulate nutrients supply in the Red Sea. Multi-sensor observation and reanalysis datasets are used to examine the relationships among dust deposition, sea surface temperature (SST), and wind speed, as they may contribute to anomalous phytoplankton blooms, through time-series and correlation analyses. A positive correlation was found at 0–3 months lag between chlorophyll-a (Chl-a) anomalies and dust anomalies over the Red Sea regions. Dust deposition process was further examined with dust aerosols’ vertical distribution using satellite lidar data. Conversely, a negative correlation was found at 0–3 months lag between SST anomalies …
First Assessment On The Air Co2 Dynamic In The Show Caves Of Tropical Karst, Vietnam, Duc A. Trinh, Quan H. Trinh, Angel Fernández-Cortés, David Mattey, Javier G. Guinea
First Assessment On The Air Co2 Dynamic In The Show Caves Of Tropical Karst, Vietnam, Duc A. Trinh, Quan H. Trinh, Angel Fernández-Cortés, David Mattey, Javier G. Guinea
International Journal of Speleology
In this study, air, water, and host rock in show caves in a Vietnam’s karst region was monitored and analyzed to identify the ventilation regime and track the cave air CO2 sources. In general, the studied caves are well ventilated. In dynamic – multiple entrance caves, air ventilation is described with the use of U shape model. In static – single entrance cave, air circulation is explained by cold air trap model. Both ventilation models suggest that air is more circulated in winter than in summer. Seasonally, the cave air CO2 increases from early spring to summer. Value …
Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet
Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet
Posters-at-the-Capitol
Assessing the Periodic Groundwater Flow Conditions of a Perched Aquifer System in the Daniel Boone National Forest
Ethan Sweet and Jonathan Malzone
Eastern Kentucky University, Department of Geosciences
Natural ephemeral wetlands situated among the ridge-tops in the Daniel Boone National Forest serve as reservoirs that recharge a shallow groundwater system. Unique interactions between surface and groundwater in these isolated systems provide substantial support for the native ecosystem, serving as a breeding ground for amphibians and as source water for vegetation—especially in periods of drought. Currently it is not understood how groundwater could provide regional biodiversity, a drought buffer, or a …
Mediation Of Eutrophication Of Surface And Subsurface Water From Non-Point Sources: Nutrient Monitoring At Meadowbrook Farm (Madison County, Kentucky), Walter S. Borowski, Jonathan M. Malzone
Mediation Of Eutrophication Of Surface And Subsurface Water From Non-Point Sources: Nutrient Monitoring At Meadowbrook Farm (Madison County, Kentucky), Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Non-point sources from various human activities such as farming have replaced industrial point sources as contributors of many contaminants in surface and subsurface waters of the United States. Eastern Kentucky University’s Meadowbrook Farm (720 acres, ~2.9 km2; Madison County, Kentucky) is a teaching facility dedicated to improving farming techniques and discovering best practices for farm operations that include minimizing environmental impacts. Agricultural activities on the Farm contribute nutrients to the Muddy Creek (Kentucky River) watershed that promote eutrophication and degrade water quality. Farm management already uses protocols to mediate drainage of dissolved nitrogen off the Farm, but also …
Nutrient Contamination From Non-Point Sources: Dissolved Nitrate And Ammonium In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Hunter R. Evans, Walter S. Borowski, Jonathan M. Malzone
Nutrient Contamination From Non-Point Sources: Dissolved Nitrate And Ammonium In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Hunter R. Evans, Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Agricultural activities often contaminate watersheds with excess nutrients leading to poor water quality and eutrophication. We assayed dissolved nutrient levels in surface and subsurface waters of Eastern Kentucky University’s Meadowbrook Farm in order to assess levels of dissolved nutrients leaving its farmland and draining into the Muddy Creek watershed. The Farm raises both crops and livestock so that nutrient sources include fertilizer and manure. We sampled springs, runoff, and subsurface pipe drainage as well as Muddy Creek on six days from May to August 2016 under a variety of weather conditions. Using established, standard colorimetric methods, we measured nitrate (NO …
Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone
Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Farms are non-point sources for nutrient contaminants that drain into watersheds and contribute to eutrophication and other environmental problems. Eastern Kentucky University’s Meadowbrook Farm raises both crops and livestock, causing dissolved phosphorus in the form of orthophosphate (PO43-) from fertilizer and animal manure to enter surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River.
We sampled surface water, springs, and water from French drains that emanate from the farm, and also sampled Muddy Creek waters from May through August 2016. Typically, 1 to 2 days after sampling, we colorimetrically measured dissolved …
Patterns Of Nutrient Export For A Typical Non-Point Source, Meadowbrook Farm, Madison County, Kentucky, James Scott Winter, Walter S. Borowski, Jonathan M. Malzone
Patterns Of Nutrient Export For A Typical Non-Point Source, Meadowbrook Farm, Madison County, Kentucky, James Scott Winter, Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Excess nutrients are found in watersheds originating from active farmland often causing poor water quality and eutrophication in natural waters. Use of fertilizer and animal husbandry can contaminate both surface water and groundwater. Eastern Kentucky University’s Meadowbrook Farm raises crops and livestock and is typical of farms that contribute excess nutrient contaminants to watersheds as non-point sources. An instrumented weir is positioned within a key sub-watershed of the Farm that empties into Muddy Creek, a tributary of the Kentucky River. This drainage is the largest outlet from the Farm that is representative of the Farm’s collective activities.
We measured flow …
Riparian Buffered Sinkholes In The Blue River Watershed, Colin Copler
Riparian Buffered Sinkholes In The Blue River Watershed, Colin Copler
Undergraduate Theses
Riparian vegetation along streams has many positive effects on water quality and macroinvertebrate communities, especially in agricultural areas. Some of these effects include erosion prevention, pollutant removal, and lower summer water temperatures. There has been much research done examining the link between these riparian areas and streams; however, riparian vegetation is understudied in karst areas. Karst is a geologic formation that is composed of limestone, which dissolves in groundwater, forming sinkholes. Thus, the question this paper seeks to investigate is does riparian vegetation around sinkholes in a karst plain influence water quality within a watershed? Water quality, land cover, and …
Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone
Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Farms are non-point sources for nutrient contaminants that drain into watersheds and contribute to eutrophication and other environmental problems. Eastern Kentucky University’s Meadowbrook Farm raises both crops and livestock, causing dissolved phosphorus in the form of orthophosphate (PO43-) from fertilizer and animal manure to enter surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River.
We sampled surface water, springs, and water from French drains that emanate from the farm, and also sampled Muddy Creek waters from May through August 2016. Typically, 1 to 2 days after sampling, we colorimetrically measured dissolved …
Nutrient Contamination From Non-Point Sources: Dissolved Nitrate And Ammonium In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Hunter R. Evans, Walter S. Borowski, Jonathan M. Malzone
Nutrient Contamination From Non-Point Sources: Dissolved Nitrate And Ammonium In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Hunter R. Evans, Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Agricultural activities often contaminate watersheds with excess nutrients leading to poor water quality and eutrophication. We assayed dissolved nutrient levels in surface and subsurface waters of Eastern Kentucky University’s Meadowbrook Farm in order to assess levels of dissolved nutrients leaving its farmland and draining into the Muddy Creek watershed. The Farm raises both crops and livestock so that nutrient sources include fertilizer and manure. We sampled springs, runoff, and subsurface pipe drainage as well as Muddy Creek on six days from May to August 2016 under a variety of weather conditions. Using established, standard colorimetric methods, we measured nitrate (NO …
Limiting Nutrient Contaminants From Agricultural Non-Point Sources: Nutrient Monitoring At Eku’S Meadowbrook Farm, Madison County, Kentucky, Walter S. Borowski, Jonathan M. Malzone
Limiting Nutrient Contaminants From Agricultural Non-Point Sources: Nutrient Monitoring At Eku’S Meadowbrook Farm, Madison County, Kentucky, Walter S. Borowski, Jonathan M. Malzone
EKU Faculty and Staff Scholarship
Sources of contamination to U.S. waterways have largely shifted from industrial, point sources to agricultural and other non-point sources associated with common human activities. EKU’s Meadowbrook Farm explores best-practices in agriculture and animal husbandry that not only act to increase the efficiency of farm operations, but also to limit environmental effects such as the eutrophification of its neighboring watershed.
We recently started a collaboration with the Farm and the EKU Department of Agriculture, which are developing methods to sequester phosphorus and thus limit nutrient export to the adjacent Muddy Creek watershed. Our task is to quantify the amount of phosphorus …
Patterns And Sources Of Anthropogenic Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah J. Wolfe
Patterns And Sources Of Anthropogenic Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah J. Wolfe
EKU Faculty and Staff Scholarship
Stream systems are often affected by anthropogenic activities that affect water quality and stream ecosystems. Land use typically determines the type and quantity of anthropogenic contaminants entering natural waters. The Otter Creek watershed (170 km2; Madison County, Kentucky) consists predominantly of pasture and rural housing, with some cropland. The basin also receives runoff from the town of Richmond and a sewage treatment plant operates within the watershed. We measured concentrations of nutrients (phosphate, ammonium, nitrate) and fecal microbes to discover levels of anthropogenic contaminants affecting water quality and to identify contaminant sources.
We sampled 4 times in the …
Patterns And Sources Of Anthropogenic Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah D. Wolfe, Walter S. Borowski, Jacob L. Robin
Patterns And Sources Of Anthropogenic Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah D. Wolfe, Walter S. Borowski, Jacob L. Robin
EKU Faculty and Staff Scholarship
Stream systems are often affected by anthropogenic contaminants that affect water quality and stream ecosystems. Land use determines the type and quantity of contaminants present in natural waters. The Otter Creek watershed (170 km2; Madison County, Kentucky) consists predominantly of pasture and rural housing, with some cropland. The basin also receives runoff from the town of Richmond and a sewage treatment plant operates within the watershed. We measured concentrations of nutrients (phosphate, ammonium, nitrate) and fecal microbes to discover levels of anthropogenic contaminants affecting water quality and to identify contaminant sources.
We sampled 4 times in the summer …
Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters
Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters
University Faculty and Staff Publications
Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …
Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi
Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi
Theses and Dissertations (Comprehensive)
Peatlands have a unique biogeochemical function, characterized by an imbalance between the rates of biomass accumulation and decomposition. These characteristics facilitate the ability of peatlands to support the sequestration of nutrients and carbon. In disturbed peatlands, these functions are compromised. Thus, reclamation targets amongst other key functions, the recovery of biogeochemical functioning. These functions could serve as a measure of recovery to conditions that are present in natural analogues. This thesis examines the recovery of microbially-mediated nutrient transformation processes in a fen peatland that was constructed on a post-mining landscape in the Athabasca oil sands region, Fort McMurray, Alberta. The …
Patterns Of Anthropogenic Nutrient Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah D. Wolfe, Walter S. Borowski, Jacob L. Robin
Patterns Of Anthropogenic Nutrient Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah D. Wolfe, Walter S. Borowski, Jacob L. Robin
EKU Faculty and Staff Scholarship
We measured nutrient concentrations within the Otter Creek watershed (Madison County, Kentucky) to: (1) discover levels of anthropogenic contaminants affecting the water quality; (2) compare these measurements to a national data set; and (3) identify nutrient sources. The watershed mainly drains rural land characterized by cattle grazing, but also drains the town of Richmond. We sampled throughout the watershed to gain a representative perspective of nutrient levels and specifically targeted localities of suspected anthropogenic nutrient sources. Water samples were passed through a 0.45 mm filter, placed in pre-acidified vials, and measured one to two days after collection. Nutrients – ammonium, …
Nutrient Addition Effects On Tropical Dry Forests: A Mini-Review From Microbial To Ecosystem Scales, Jennifer S. Powers, Kristen K. Becklund, Maria G. Gei, Siddharth B. Iyengar, Rebecca Meyer, Christine S. O'Connell, Erik M. Schilling, Christina M. Smith, Bonnie G. Waring, Leland K. Werden
Nutrient Addition Effects On Tropical Dry Forests: A Mini-Review From Microbial To Ecosystem Scales, Jennifer S. Powers, Kristen K. Becklund, Maria G. Gei, Siddharth B. Iyengar, Rebecca Meyer, Christine S. O'Connell, Erik M. Schilling, Christina M. Smith, Bonnie G. Waring, Leland K. Werden
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Humans have more than doubled inputs of reactive nitrogen globally and greatly accelerated the biogeochemical cycles of phosphorus and metals. However, the impacts of increased element mobility on tropical ecosystems remain poorly quantified, particularly for the vast tropical dry forest biome. Tropical dry forests are characterized by marked seasonality, relatively little precipitation, and high heterogeneity in plant functional diversity and soil chemistry. For these reasons, increased nutrient deposition may affect tropical dry forests differently than wet tropical or temperate forests. Here, we review studies that investigated how nutrient availability affects ecosystem and community processes from the microsite to ecosystem scales …
Sources Of Nutrient And Escherichia Coli Contamination Within The Otter Creek Watershed, Madison County, Kentucky, Nathaniel C. Crockett, Walter S. Borowski
Sources Of Nutrient And Escherichia Coli Contamination Within The Otter Creek Watershed, Madison County, Kentucky, Nathaniel C. Crockett, Walter S. Borowski
EKU Faculty and Staff Scholarship
The Otter Creek watershed exhibits dissolved nutrient (ammonium, NH4; nitrate, NO3; phosphate, PO4) and Escherichia coli contamination that compromises its water quality. The watershed covers a substantial portion of Madison County and consists of Lake Reba, Dreaming Creek, and east and west forks, all of which enter the trunk of Otter Creek before flowing into the Kentucky River. Suspected contaminate sources include leaky sewage system pipes, runoff from pasture land, and septic system leachate. We collected 330 water samples on three occasions during summer 2014 to determine the extent and sources of contamination. Nutrients …
A Review Of The Hyporheic Zone, Stream Restoration, And Means To Enhance Denitrification, Leanne Merill, David J. Tonjes
A Review Of The Hyporheic Zone, Stream Restoration, And Means To Enhance Denitrification, Leanne Merill, David J. Tonjes
Technology & Society Faculty Publications
The hyporheic zone is the subsurface area below and adjacent to a stream where groundwater mixes with stream water, through vertical, lateral, and longitudinal flows. The hyporheic zone connects the stream to uplands and other terrestrial environments. It is a zone of distinct faunal communities, high biological diversity and ecological complexity, and is the site of chemical processing and transformations of ground- and stream waters. The hyporheic zone is important to the overall ecosystem ecology of the stream, and it can influence stream water chemistry. Flows, reactions, and biota in the hyporheic zone are heterogeneous and patchy, making it difficult …
Monitoring The Influence Of Acid Deposition On Soil And Implications To Forest Health In The Daniel Boone National Forest, Tyler M. Sanderson
Monitoring The Influence Of Acid Deposition On Soil And Implications To Forest Health In The Daniel Boone National Forest, Tyler M. Sanderson
Theses and Dissertations--Forestry and Natural Resources
Combustion of fossil fuels has contributed to many environmental problems including acid deposition. The Clean Air Act (CAA) was created to reduce ecological problems by cutting emissions of sulfur and nitrogen. Reduced emissions and rainfall concentrations of acidic ions have been observed since the enactment of the CAA, but soils continue to receive some acid inputs. Soils sensitive to acid deposition have been found to have low pH, a loss of base cations and a shift in the mineral phase controlling the activity of Al3+ and/or SO42-. If inputs continue, soil may be depleted of base …
Wavelength And Temperature-Dependent Apparent Quantum Yields For Photochemical Formation Of Hydrogen Peroxide In Seawater, David J. Kieber, Gary W. Miller, Patrick J. Neale, Kenneth Mopper
Wavelength And Temperature-Dependent Apparent Quantum Yields For Photochemical Formation Of Hydrogen Peroxide In Seawater, David J. Kieber, Gary W. Miller, Patrick J. Neale, Kenneth Mopper
Chemistry & Biochemistry Faculty Publications
Wavelength and temperature-dependent apparent quantum yields (AQYs) were determined for the photochemical production of hydrogen peroxide using seawater obtained from coastal and oligotrophic stations in Antarctica, the Pacific Ocean at Station ALOHA, the Gulf of Mexico, and at several sites along the East Coast of the United States. For all samples, AQYs decreased exponentially with increasing wavelength at 25 °C, ranging from 4.6 × 10−4 to 10.4 × 10−4 at 290 nm to 0.17 × 10−4 to 0.97 × 10−4 at 400 nm. AQYs for different seawater samples were remarkably similar irrespective of expected differences in the composition and concentrations …
Estimating Hydroxyl Radical Photochemical Formation Rates In Natural Waters During Long-Term Laboratory Irradiation Experiments, Luni Sun, Hongmei Chen, Hussain A. Abdulla, Kenneth Mopper
Estimating Hydroxyl Radical Photochemical Formation Rates In Natural Waters During Long-Term Laboratory Irradiation Experiments, Luni Sun, Hongmei Chen, Hussain A. Abdulla, Kenneth Mopper
Chemistry & Biochemistry Faculty Publications
In this study it was observed that, during long-term irradiations (>1 day) of natural waters, the methods for measuring hydroxyl radical (˙OH) formation rates based upon sequentially determined cumulative concentrations of photoproducts from probes significantly underestimate actual ˙OH formation rates. Performing a correction using the photodegradation rates of the probe products improves the ˙OH estimation for short term irradiations (<1 day), but not long term irradiations. Only the ‘instantaneous’ formation rates, which were obtained by adding probes to aliquots at each time point and irradiating these sub-samples for a short time (≤2 h), were found appropriate for accurately estimating ˙OH photochemical formation rates during long-term laboratory irradiation experiments. Our results also showed that in iron- and dissolved organic matter (DOM)-rich water samples, ˙OH appears to be mainly produced from the Fenton reaction initially, but subsequently from other sources possibly from DOM photoreactions. Pathways of ˙OH formation in long-term irradiations in relation to H2O2 and iron concentrations are discussed.
Wetlands And Greenhouse Gas Fluxes: Causes And Effects Of Climate Change – A Meta-Analysis, Robert E. Ventura
Wetlands And Greenhouse Gas Fluxes: Causes And Effects Of Climate Change – A Meta-Analysis, Robert E. Ventura
Pomona Senior Theses
Climate change is one of the largest problems facing this generation. Anthropogenically caused increases of greenhouse gas emissions is a significant culprit to this problem. Although the obvious problems such as cars, industry, and urbanism garnish a significant amount of the criticism, natural sources such as wetlands are also beginning to contribute to this issue. This is becoming increasingly significant as wetlands shift from being sinks of greenhouse gases to becoming sources as various anthropogenic impacts, including global warming itself, begin to affect the health of the wetlands. The aim of this project is to look at four common types …
Sources Of Nutrient And Fecal Microbe Pollution In Otter Creek, Madison County, Kentucky, Kandice L. Smith, Walter S. Borowski
Sources Of Nutrient And Fecal Microbe Pollution In Otter Creek, Madison County, Kentucky, Kandice L. Smith, Walter S. Borowski
EKU Faculty and Staff Scholarship
We measured nutrient (nitrate, ammonium, phosphate) and fecal microbe concentrations in surface waters of the Otter Creek watershed, Madison County, Kentucky to access sources of these contaminants. The watershed is approximately 12.5 miles long covering ~169 km2 (41,832 acres). The watershed includes East Fork, West Fork, and Dreaming Creek, all tributaries to the main trunk of Otter Creek. The upper portion of the main trunk and Dreaming Creek drain urban areas of Richmond, but 85% of total watershed area is agricultural land, used mainly for grazing cattle. Rural residential areas and woodlands also occur.
The principle contaminants are nutrients …
The Impact Of Nitrogen Contamination And River Modification On A Mississippi River Floodplain Lake, Indu Karthic, Richard B. Brugam Ph.D., William A. Retzlaff, Kevin Johnson
The Impact Of Nitrogen Contamination And River Modification On A Mississippi River Floodplain Lake, Indu Karthic, Richard B. Brugam Ph.D., William A. Retzlaff, Kevin Johnson
SIUE Faculty Research, Scholarship, and Creative Activity
Anthropogenic nitrogen contamination has increased in ecosystems around the world (frequently termed the “nitrogen cascade”). Coke production for steel manufacturing is often overlooked as a source of nitrogen to natural ecosystems. We examined sediment cores from a Horseshoe Lake, a floodplain lake located just East of St. Louis Missouri (USA) to test whether a coking plant effluent could be traced using stable isotopes of nitrogen and diatom microfossils. The distribution of δ15N values in surface sediment samples from the lake shows the highest values near the coking plant effluent. Analysis stable isotopes of nitrogen from sediment cores using …
Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander
Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander
School of Natural Resources: Dissertations, Theses, and Student Research
Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …
Natural And Constructed Wetlands For Ecosystem And Engineering Services In The Arid And Semi-Arid Regions, Achyut Raj Adhikari
Natural And Constructed Wetlands For Ecosystem And Engineering Services In The Arid And Semi-Arid Regions, Achyut Raj Adhikari
UNLV Theses, Dissertations, Professional Papers, and Capstones
The Las Vegas Wash (LVW) has undergone significant wetlands degradation and soil erosion over the past thirty years due to increasing flow resulting from urbanization and large rainfall events in the Las Vegas Valley Watershed. The increased flow and associated pollution load in the LVW and its adverse impact in Lake Mead have alerted stakeholders to pay a greater attention to explore alternative measures for rehabilitation of wetland ecosystems. This dissertation, using the case of changes in LVW, analyzes and describes ecological and engineering services provided by wetlands in arid and semi-arid regions and provides a knowledge base that can …
Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara
Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara
Open Access Theses & Dissertations
Almost half the global soil organic carbon pool is found in northern high latitudes. The majority of this soil carbon is stored in a greenhouse inert state within permafrost. As pronounced warming of high northern latitudes ensues, there is a strong likelihood that this substantial soil organic carbon pool will be mobilized to the atmosphere where it is likely to positively enhance greenhouse warming. Modeling studies suggest this positive feedback could alter future climate states of the Arctic and the globe, and affect how humans may need to adapt to climate change. Accordingly, understanding the patterns and controls and the …
Nutrient And Fecal Microbe Assessment Of The Water Quality Of Tates Creek, Madison County, Kentucky, Krisopher H. Carroll, Walter S. Borowski
Nutrient And Fecal Microbe Assessment Of The Water Quality Of Tates Creek, Madison County, Kentucky, Krisopher H. Carroll, Walter S. Borowski
EKU Faculty and Staff Scholarship
Tates Creek is a significant tributary to the Kentucky River that has shown high levels of microbial and nutrient pollution. We sampled the waters of Tates Creek comprehensively by occupying 25 stations along its 13-mile length, collecting stream water at the confluence of major tributaries from its headwaters to the Kentucky River. Samples were collected four times between May and August 2011 during dry periods as well as immediately after rainfall events.
We measured ammonium (NH4+), nitrate (NO3-) and phosphate (PO4-) concentrations using colorimetry. Microbial samples were measured for total coliform …
Spatial Patterns Of Drought Triggers And Indicators, Joseph P. Robine
Spatial Patterns Of Drought Triggers And Indicators, Joseph P. Robine
Department of Environmental Studies: Undergraduate Student Theses
Drought is a reoccurring phenomenon with widespread economic, social, and environmental impacts. Unlike other disasters, a drought cannot be easily detected. In addition, droughts are widespread and develop slowly over time making it difficult to detect its onset and monitor its severity and impacts. To assist in monitoring the severity and spatial extent of droughts, drought managers frequently use indicators and triggers. Drought indicators are meteorological or hydrological variables or indices that quantify or describe the level of drought severity. A drought trigger is a value of an indicator that initiates management and response actions. Despite the clear importance of …