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Full-Text Articles in Fresh Water Studies

Effects Of Landscape Disturbances On Autotrophic Processes Within Arkansas Ozark Streams, Bradley J. Austin May 2015

Effects Of Landscape Disturbances On Autotrophic Processes Within Arkansas Ozark Streams, Bradley J. Austin

Graduate Theses and Dissertations

Land-use change is one of the most widespread human impacts and can influence abiotic and biotic processes within surrounding streams. For example, streams in agricultural and urban watersheds receive greater light and nutrient inputs that can promote increased algal growth and primary production. Natural gas (NG) infrastructure development, a recent land use change in many regions, may also stimulate forested stream primary production, by reducing forest cover and increasing sediments and nutrient transport. I sampled streams across a NG activity gradient for algal biomass and gross primary production (GPP) to assess potential effects of this emerging land-use type. Algal biomass …


Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle Jan 2015

Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle

Theses and Dissertations

Abstract

The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus, Mitchell) is an anadromous species that spawns in tidal freshwater rivers from Canada to Florida. Overfishing, river sedimentation and alteration of the river bottom have decreased Atlantic Sturgeon populations, and NOAA lists the species as endangered. Ecologists sometimes find it difficult to locate individuals of a species that is rare, endangered or invasive. The need for methods less invasive that can create more resolution of cryptic species presence is necessary. Environmental DNA (eDNA) is a non-invasive means of detecting rare, endangered, or invasive species by isolating nuclear or mitochondrial DNA (mtDNA) from the …


River Report. State Of The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, Contaminants, 2015, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Lucy Sonnenberg, Gerry Pinto, Nisse Goldberg, Anthony Ouellette, Gretchen Bielmyer-Fraser, Stuart J. Chalk, Peter Bacopoulos, Brian P. Zoellner Jan 2015

River Report. State Of The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, Contaminants, 2015, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Lucy Sonnenberg, Gerry Pinto, Nisse Goldberg, Anthony Ouellette, Gretchen Bielmyer-Fraser, Stuart J. Chalk, Peter Bacopoulos, Brian P. Zoellner

State of the River Report

No abstract provided.


Application Of High-Resolution Spectral Absorbance Measurements To Determine Dissolved Organic Carbon Concentration In Remote Areas, Armine Avagyan, Benjamin R. K. Runkle, Lars Kutzbach Sep 2014

Application Of High-Resolution Spectral Absorbance Measurements To Determine Dissolved Organic Carbon Concentration In Remote Areas, Armine Avagyan, Benjamin R. K. Runkle, Lars Kutzbach

Biological and Agricultural Engineering Faculty Publications and Presentations

Accurate quantification of dissolved organic carbon (DOC) in surface and soil pore waters is crucial for understanding changes in water resources under the influence of climate and land use changes. Sampling and laboratory analysis of DOC content at a sufficient temporal frequency are especially difficult to achieve for natural DOC sources like the extensive boreal and arctic mire landscapes due to their remoteness. Therefore, the goals of this paper are (1) to investigate the performance of a portable, high-resolution ultraviolet–visible light spectroscopic method for determining the DOC content of surface and soil pore water samples from a boreal mire complex …


The Saco River Plume: A Discussion Of The Near-Field Dynamics, Barbara A. Fortier Jul 2014

The Saco River Plume: A Discussion Of The Near-Field Dynamics, Barbara A. Fortier

All Theses And Dissertations

This study focused on the freshwater discharge plume from the Saco River in southwestern Maine to determine the mechanisms responsible for the largest impacts on the near-field dynamics in this region. We examined the forcing factors that tended to increase the plume's spatial extent upshelf of the river mouth. Salinity, temperature, and density data were collected during cruises from May through November 2010 and by two surface moorings deployed upshelf of the Saco River mouth. We found a distinct variation in the latitude of the upshelf boundary of the plume during and after periods of high discharge. Furthermore, we found …


Harvest Incentives: A Tool For Managing Aquatic Invasive Species, Bob Wiltshire, Nathan Stone, Marshall Meyers, Bill Hyatt, Lori Williams, Jason Goldberg, Susan Pasko, Leah Elwell May 2014

Harvest Incentives: A Tool For Managing Aquatic Invasive Species, Bob Wiltshire, Nathan Stone, Marshall Meyers, Bill Hyatt, Lori Williams, Jason Goldberg, Susan Pasko, Leah Elwell

National Invasive Species Council

Conclusion

The success of any harvest incentive program to address aquatic invasive species will depend upon numerous biological, socioeconomic, and legal considerations. Programs that encourage harvest may be a successful management tool in targeting small, distinct populations; in high priority areas within a larger invasion; or they may play a supplementary role within larger control programs. Their use, however, will require careful review, planning, and monitoring to ensure success and that they do not unintentionally lead to further spread of invasive species, cause additional harm to native species, or waste valuable resources.


Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr May 2014

Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr

Electronic Theses and Dissertations

The future of Lake Baikal’s biodiversity is uncertain in response to climate change. Unlike its diverse benthos, Lake Baikal’s zooplankton is species poor, with up to 96% of its biomass being composed of a single Calanoid copepod species, Epischura baikalensis. This study characterizes the genetic differentiation and differential gene expression of E. baikalensis. Using partial-transcriptome sequences obtained by 454 Rosche and Illumina sequencing technologies, the genetic differentiation at inferred single nucleotide polymorphism (SNP) sites and differential gene expression in populations sampled from various parts of the lake were analyzed. The functional genomics of genes showed significant differential …


Seasonal Variability As A Source Of Uncertainty In The West Siberian Regional Ch4 Flux Upscaling, A. F. Sabrekov, Benjamin R. K. Runkle, M. V. Glagolev, I E. Kleptsova, S. S. Maksyutov Apr 2014

Seasonal Variability As A Source Of Uncertainty In The West Siberian Regional Ch4 Flux Upscaling, A. F. Sabrekov, Benjamin R. K. Runkle, M. V. Glagolev, I E. Kleptsova, S. S. Maksyutov

Biological and Agricultural Engineering Faculty Publications and Presentations

This study compares seasonal and spatial variations in methane fluxes as sources of uncertainty in regional CH4 flux upscaling from the wetlands of West Siberia. The study examined variability in summertime CH4 emissions from boreal peatlands, with a focus on two subtaiga fen sites in the southern part of West Siberia (Novosibirskaya oblast). We measured CH4 flux, water table depth, air and peat temperature, pH and electric conductivity of peat water during three field campaigns in summer 2011 (9–12 July, 26–28 July and 20–21 August). Fluxes were measured with static chambers at sites chosen to represent two of the most …


The Surface Energy Balance And Its Drivers In A Boreal Peatland Fen Of Northwestern Russia, Benjamin R. K. Runkle, Christian Wille, Michal Gazovic, M. Wilmking, L. Kutzbach Apr 2014

The Surface Energy Balance And Its Drivers In A Boreal Peatland Fen Of Northwestern Russia, Benjamin R. K. Runkle, Christian Wille, Michal Gazovic, M. Wilmking, L. Kutzbach

Biological and Agricultural Engineering Faculty Publications and Presentations

Boreal peatland energy balances using the eddy covariance technique have previously been made in Alaska, Canada, Scandinavia, and Western Siberia, but not in the European portion of the Russian Federation. European Russia contains approximately 200,000 km2 of peatlands and has a boreal (subarctic), continental climate influencing the region’s energy balance. To help fill this research gap, the surface energy balance was determined for a boreal peatland fen in the Komi Republic of Russia for an 11-month period in 2008–2009 using the eddy covariance method. The total measurement period’s cumulative energy balance closure rate was 86%, with higher closure during the …


Issue Brief: Asset Management For Stormwater, New England Environmental Finance Center, Sustainable Communities Learning Network Apr 2014

Issue Brief: Asset Management For Stormwater, New England Environmental Finance Center, Sustainable Communities Learning Network

Sustainable Communities Capacity Building

Asset management is a strategic approach to maintaining and sustaining infrastructure in order to meet the needs of the community at the lowest overall life cycle cost. This approach helps communities know how and where to prioritize limited funds in order to achieve the greatest benefit. Often applied to drinking water and wastewater infrastructure, this method is well suited to managing any assets, including stormwater systems.

This issue brief is intended to introduce local governments to the asset management process and to show how it can be applied in managing stormwater assets. It was adapted from an appendix written by …


Salinity Risk Mapping For Assessing Carbon Farming Initiative Proposals: Decision Support And Data Requirements, Paul Raper, Peter Gardiner Apr 2014

Salinity Risk Mapping For Assessing Carbon Farming Initiative Proposals: Decision Support And Data Requirements, Paul Raper, Peter Gardiner

Resource management technical reports

The Clean Energy Legislation passed by the Australian Parliament on 8 November 2011 links the carbon price to the Carbon Farming Initiative (CFI). Under the Carbon Credits (Carbon Farming Initiative) Act 2011 (the Act), proponents need to consider regional natural resource management (NRM) plans to ensure that tree plantings for carbon bio-sequestration maximise environmental benefits and avoid unintended adverse effects on biodiversity, water and agricultural production systems.


Effects Of Urban Stream Burial On Organic Matter Dynamics And Reach Scale Nitrate Retention, Jake J. Beaulieu, Paul M. Mayer, Sujay S. Kaushal, Michael J. Pennino, Clay P. Arango, David A. Balz, Timothy J. Canfield, Colleen M. Elonen, Ken M. Fritz, Brian H. Hill, Hodon Ryu, Jorge W. Santo Domingo Apr 2014

Effects Of Urban Stream Burial On Organic Matter Dynamics And Reach Scale Nitrate Retention, Jake J. Beaulieu, Paul M. Mayer, Sujay S. Kaushal, Michael J. Pennino, Clay P. Arango, David A. Balz, Timothy J. Canfield, Colleen M. Elonen, Ken M. Fritz, Brian H. Hill, Hodon Ryu, Jorge W. Santo Domingo

All Faculty Scholarship for the College of the Sciences

Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO3 ) by eliminating primary production, reducing respiration rates and organic matter availability, and increasing specific discharge. We tested these predictions by measuring whole-stream NO3 removal rates using 15NO3 isotope tracer releases in paired buried and open reaches in three streams in Cincinnati, Ohio (USA) during four seasons. Nitrate uptake lengths were 29 times …


Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall Apr 2014

Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall

Virginia Journal of Science

Phytoplankton composition from 16 Virginia lakes and reservoirs are discussed with emphasis on the dominant taxa, algal bloom producers, and potentially harmful species at these locations. This is a companion study to the more comprehensive publication regarding Virginia freshwater phytoplankton by Marshall (2013).


The Effects That Liquid And Solid Cattle Manure Have On The Water Quality Of Drainage Ditches In Putnam County, Ohio, Janelle Horstman Jan 2014

The Effects That Liquid And Solid Cattle Manure Have On The Water Quality Of Drainage Ditches In Putnam County, Ohio, Janelle Horstman

Honors Projects

Lake Erie has experienced harmful algal blooms with increased frequency since the mid-1990s due to excess nutrients from Rivers, such as the Maumee River, and largely agricultural watersheds. Nonpoint source pollution from agriculture contributes to eutrophication, algal blooms, and the degradation of water quality. This creates stress on aquatic fauna, reduced aesthetic quality, odor, and limits of the water for usage of drinking, recreation, and industry. This research paper asks what the contributions of having access to manure application records, soil records, and information about antibiotics have on what is known about manure management and antibiotic resistance, which has been …


Distribution, Habitat Preference, And Status Of The Ditch Fencing Crayfish, Faxonella Clypeata (Hay) (Decapoda: Cambaridae), In Arkansas, H. W. Robison, C. T. Mcallister Jan 2014

Distribution, Habitat Preference, And Status Of The Ditch Fencing Crayfish, Faxonella Clypeata (Hay) (Decapoda: Cambaridae), In Arkansas, H. W. Robison, C. T. Mcallister

Journal of the Arkansas Academy of Science

The ditch fencing crayfish, Faxonella clypeata (Hay), is a common and widespread crayfish that inhabits roadside ditches, intermittent first-order streams, shallow sloughs with heavy vegetation, and edges of swamps in Arkansas. Between 1997-2012, we made 55 collections of F. clypeata in 34 counties throughout eastern Arkansas, including 23 counties where F. clypeata had not been previously documented. At most of these locations within the West Gulf Coastal and Mississippi Alluvial Plain provinces, F. clypeata was found to be a locally abundant crayfish. With regard to conservation status, F. clypeata should be considered as “Currently Stable” due to its widespread distribution …


Urban Stream Syndrome In A Small Town: A Comparative Study Of Sager And Flint Creeks, T. S. Wakefield Jan 2014

Urban Stream Syndrome In A Small Town: A Comparative Study Of Sager And Flint Creeks, T. S. Wakefield

Journal of the Arkansas Academy of Science

Utilizing rapid bioassessment procedures and aquatic physiochemical techniques, a three-year investigation of Sager and Flint creeks was completed. Bioassessment indices and physiochemical parameters of the 2 streams were compared and the effects of urbanization on both watersheds were assessed. Correlating data concerning land usage in both watersheds and alterations of both streams' geomorphology were also utilized to conclude that Sager Creek shows a higher degree of urban stream syndrome than Flint Creek.


Reproductive Phase Determination In Male Meagre (Argyrosomus Regius, Sciaenidae): Testis Development And Histologic Corroboration Of A Gross Anatomical Scale, Nuno Prista, Leonel Gordo, Jose L. Costa, Maria J. Costa, Cynthia M. Jones Jan 2014

Reproductive Phase Determination In Male Meagre (Argyrosomus Regius, Sciaenidae): Testis Development And Histologic Corroboration Of A Gross Anatomical Scale, Nuno Prista, Leonel Gordo, Jose L. Costa, Maria J. Costa, Cynthia M. Jones

OES Faculty Publications

Reproductive stage determination of male gonads has received sparse attention in fish biology literature with few studies detailing the building of gross anatomical-and histologic scales. The meagre (Argyrosomus regius) is one of the world's largest sciaenids and supports a significant regional fishery in European and North African waters whose reproductive patterns are yet to be fully investigated. In the present study, we derive a macroscopic grading system for meagre testis using semi-quantitative graphs that feature the testis variability along the species size range and time of the year. We then describe the histological stages and reproductive phases of …


Emergence Of Algal Blooms: The Effects Of Short-Term Variability In Water Quality On Phytoplankton Abundance, Diversity, And Community Composition In A Tidal Estuary, Todd A. Egerton, Ryan E. Morse, Harold G. Marshall, Margaret R. Mulholland Jan 2014

Emergence Of Algal Blooms: The Effects Of Short-Term Variability In Water Quality On Phytoplankton Abundance, Diversity, And Community Composition In A Tidal Estuary, Todd A. Egerton, Ryan E. Morse, Harold G. Marshall, Margaret R. Mulholland

OES Faculty Publications

Algal blooms are dynamic phenomena, often attributed to environmental parameters that vary on short timescales (e.g., hours to days). Phytoplankton monitoring programs are largely designed to examine long-term trends and interannual variability. In order to better understand and evaluate the relationships between water quality variables and the genesis of algal blooms, daily samples were collected over a 34 day period in the eutrophic Lafayette River, a tidal tributary within Chesapeake Bay's estuarine complex, during spring 2006. During this period two distinct algal blooms occurred; the first was a cryptomonad bloom and this was followed by a bloom of the mixotrophic …


Reducing Water Extractable Phosphorus In Poultry Litter Using Chitosan Treatment, Zachary Simpson, Brina Smith, David A. Zaharoff, Brian E. Haggard Jan 2014

Reducing Water Extractable Phosphorus In Poultry Litter Using Chitosan Treatment, Zachary Simpson, Brina Smith, David A. Zaharoff, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Phosphorus (P) is an important factor in the eutrophication of freshwater, and watershed sources include effluent discharges and the landscape. Poultry litter applied to the landscape can be a potential source of P, which is dependent on rainfall, runoff and dissolution. Chitosan, the deacetylated form of the biopolymer chitin, has been shown to have an effect on reducing water extractable phosphorus (WEP) in poultry litter when applied as a powder. The intent of this study was to measure the effect that poultry litter treatment (PLT), acetic acid and incubation time have on chitosan’s ability to reduce WEP in poultry litter. …


State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2014, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Lucy Sonnenberg, Gerry Pinto, Nisse Goldberg, Kimberly Mann, Radha Pyati, Gretchen Bielmyer-Fraser, Stuart Chalk, Peter Bacopoulos, Brian P. Zoellner Jan 2014

State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2014, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Lucy Sonnenberg, Gerry Pinto, Nisse Goldberg, Kimberly Mann, Radha Pyati, Gretchen Bielmyer-Fraser, Stuart Chalk, Peter Bacopoulos, Brian P. Zoellner

State of the River Report

No abstract provided.


Evolution Of The Freshwater Sardinella, Sardinella Tawilis (Clupeiformes: Clupeidae), In Taal Lake, Philippines And Identification Of Iits Marine Sister-Species, Sardinella Hualiensis, Demian Willette, Kent E. Carpenter, Mudjekeewis Santos Jan 2014

Evolution Of The Freshwater Sardinella, Sardinella Tawilis (Clupeiformes: Clupeidae), In Taal Lake, Philippines And Identification Of Iits Marine Sister-Species, Sardinella Hualiensis, Demian Willette, Kent E. Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

We identify the sister species of the world's only freshwater sardinella, Sardinella tawilis (Herre, 1927) of Taal Lake, Philippines as the morphologically-similar marine Taiwanese sardinella Sardinella hualiensis (Chu and Tsai, 1958). Evidence of incomplete lineage sorting and a species tree derived from three mitochondrial genes and one nuclear gene indicate that S. tawilis diverged from S. hualiensis in the late Pleistocene. Neutrality tests, mismatch distribution analysis, sequence diversity indices, and species tree analysis indicate populations of both species have long been stable and that the divergence between these two lineages occurred prior to the putative 18th century formation of Taal …


Understanding Basin Specific Life History Characteristics Of Lake Mead Quagga Mussels (Dreissena Bugensis) And A Potential Treatment Using Uv Radiation In Laboratory Studies, Melissa Thaw Aug 2013

Understanding Basin Specific Life History Characteristics Of Lake Mead Quagga Mussels (Dreissena Bugensis) And A Potential Treatment Using Uv Radiation In Laboratory Studies, Melissa Thaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

The quagga mussel (Dreissena bugensis) is an aquatic invasive species that is spreading throughout Lake Mead and other western waterways. Unlike their native waters in Eurasia, Lake Mead exhibits year round warm temperatures, high calcium levels and a lack of natural predators, all of which are very favorable conditions for their growth and spread. Dreissena bugensis reproduce and colonize hard surfaces rapidly, where they filter large amounts of water. They disrupt the aquatic food chain and interfere with infrastructure that is exposed to lake water. There is an urgent need to understand Dreissena bugensis life history characteristics within this new …


Fish Species Distribution In Seagrass Habitats Of Chesapeake Bay Are Structured By Abiotic And Biotic Factors, Jason J. Schaffler, Jacques Van Montfrans, Cynthia M. Jones, Robert J. Orth Jul 2013

Fish Species Distribution In Seagrass Habitats Of Chesapeake Bay Are Structured By Abiotic And Biotic Factors, Jason J. Schaffler, Jacques Van Montfrans, Cynthia M. Jones, Robert J. Orth

OES Faculty Publications

Seagrass habitats have long been known to serve as nursery habitats for juvenile fish by providing refuges from predation and areas of high forage abundance. However, comparatively less is known about other factors structuring fish communities that make extensive use of seagrass as nursery habitat. We examined both physical and biological factors that may structure the juvenile seagrass-associated fish communities across a synoptic-scale multiyear study in lower Chesapeake Bay. Across 3years of sampling, we collected 21,153 fish from 31 species. Silver Perch Bairdiella chrysoura made up over 86% of all individuals collected. Nine additional species made up at least 1% …


Understanding Effects Of Changes In Land Use, Environmental Parameters, Habitat Characteristics On The Great Basin Aquatic Invertebrates Using Ecological Stoichiometric Theory, Knut Mehler May 2013

Understanding Effects Of Changes In Land Use, Environmental Parameters, Habitat Characteristics On The Great Basin Aquatic Invertebrates Using Ecological Stoichiometric Theory, Knut Mehler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many freshwater ecosystems in the Great Basin have undergone dramatic alteration over the past decades due to groundwater withdrawal, water diversion and changes in land use. These changes have affected benthic food web dynamics by altering the availability of chemical key elements for primary and secondary producers, by loss of biodiversity and extinction of endemic species. However, only few studies are available that addresses the link between changes in land use, habitat characteristics and its effects on benthic macroinvertebrates (BMI) communities comprehensively and little attention has been given to integrating physiochemical aspects to link ecosystem functions.

This dissertation analyzes the …


Assessment Of A Rotenone Application Event At Mormon Island West Lake In Central Nebraska, Keith D. Koupal, Brian C. Peterson, Casey W. Schoenebeck Mar 2013

Assessment Of A Rotenone Application Event At Mormon Island West Lake In Central Nebraska, Keith D. Koupal, Brian C. Peterson, Casey W. Schoenebeck

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Fisheries managers applied rotenone to Mormon Island West in August of 2010 to renovate a fish community that was hypothesized to be unbalanced (i.e., dominated with gizzard shad and common carp) based on standardized survey results. We estimated species-specific biomass following the lake renovation to provide a baseline biomass estimate for a sand pit lake and to evaluate the effectiveness of standardized sampling gears. Gizzard shad (Dorosoma cepedianum) were abundant in all sampling gears, but mostly stock-size (>175 mm total length) and larger individuals were caught in gill and trap nets and sub-stock (≤175 mm total length) …


Bulk Partitioning The Growing Season Net Ecosystem Exchange Of Co2 In Siberian Tundra Reveals The Seasonality Of Its Carbon Sequestration Strength, Benjamin R. K. Runkle, T. Sachs, C. Wille, E.-M. Pfeiffer, L. Kutzbach Mar 2013

Bulk Partitioning The Growing Season Net Ecosystem Exchange Of Co2 In Siberian Tundra Reveals The Seasonality Of Its Carbon Sequestration Strength, Benjamin R. K. Runkle, T. Sachs, C. Wille, E.-M. Pfeiffer, L. Kutzbach

Biological and Agricultural Engineering Faculty Publications and Presentations

This paper evaluates the relative contribution of light and temperature on net ecosystem CO2 uptake during the 2006 growing season in a polygonal tundra ecosystem in the Lena River Delta in Northern Siberia (72°22´ N, 126°30´ E). The occurrence and frequency of warm periods may be an important determinant of the magnitude of the ecosystem's carbon sink function, as they drive temperature-induced changes in respiration. Hot spells during the early portion of the growing season, when the photosynthetic apparatus of vascular plants is not fully developed, are shown to be more influential in creating positive mid-day surface-to-atmosphere net ecosystem CO2 …


Application Of Remote Sensing In Aquatic Ecosystems, Foad Yousef Jan 2013

Application Of Remote Sensing In Aquatic Ecosystems, Foad Yousef

Dissertations, Master's Theses and Master's Reports - Open

I utilized state the art remote sensing and GIS (Geographical Information System) techniques to study large scale biological, physical and ecological processes of coastal, nearshore, and offshore waters of Lake Michigan and Lake Superior. These processes ranged from chlorophyll a and primary production time series analysies in Lake Michigan to coastal stamp sand threats on Buffalo Reef in Lake Superior. I used SeaWiFS (Sea-viewing Wide Field-of-view Sensor) satellite imagery to trace various biological, chemical and optical water properties of Lake Michigan during the past decade and to investigate the collapse of early spring primary production. Using spatial analysis techniques, I …


Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall Jan 2013

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Virginia Journal of Science

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …


Short-Term Denitrification In The Metalimnion Of A Eutrophic Reservoir, Aki Kogo, Erin M. Grantz, Thad Scott Jan 2013

Short-Term Denitrification In The Metalimnion Of A Eutrophic Reservoir, Aki Kogo, Erin M. Grantz, Thad Scott

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Denitrification in metalimnetic water was examined under different conditions to determine how addition of nitrate (NO3 -) and particulate carbon (PC), aeration, and concentrations of nitrate affect denitrification. In the first experiment, water samples from a metalimnion were treated with different combinations of NO3 - and PC. Changes in excess N2 -N concentration for 10 days were measured using membrane inlet mass spectrometry (MIMS). The second experiment used the same treatments as the first experiment after aeration of water. Besides excess N2 -N concentrations, O2 concentrations were measured for 16 days. The third experiment examined how different initial concentrations of …


Relationship Between Land-Use And Water Quality In Spring-Fed Streams Of The Ozark National Forest, A. Smartt, S. Ganguly, M. A. Evans-White, B. E. Haggard Jan 2013

Relationship Between Land-Use And Water Quality In Spring-Fed Streams Of The Ozark National Forest, A. Smartt, S. Ganguly, M. A. Evans-White, B. E. Haggard

Journal of the Arkansas Academy of Science

Spring-fed streams are abundant in karst topographic regions such as the Ozarks, providing an important and valuable water resource. Many of these spring-fed streams presently receive agriculture runoff, but few studies have examined the impacts of this runoff on water quality. We examined water quality in Ozark spring-fed streams surrounded by either agricultural (N=3) or primarily forested land (N=3) in the riparian zone. We hypothesized that agricultural sites would have greater dissolved nutrient concentrations and conductivity than forested sites and that water quality would fluctuate with distance from the spring source. Conductivity (p