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Full-Text Articles in Physical Sciences and Mathematics

Nitrite Cycling In The Primary Nitrite Maxima Of The Eastern Tropical North Pacific, Nicole M. Travis, Colette L. Kelly, Margaret R. Mulholland, Karen L. Casciotti Jan 2023

Nitrite Cycling In The Primary Nitrite Maxima Of The Eastern Tropical North Pacific, Nicole M. Travis, Colette L. Kelly, Margaret R. Mulholland, Karen L. Casciotti

OES Faculty Publications

The primary nitrite maximum (PNM) is a ubiquitous feature of the upper ocean, where nitrite accumulates in a sharp peak at the base of the euphotic zone. This feature is situated where many chemical and hydrographic properties have strong gradients and the activities of several microbial processes overlap. Near the PNM, four major microbial processes are active in nitrite cycling: ammonia oxidation, nitrite oxidation, nitrate reduction and nitrite uptake. The first two processes are mediated by the nitrifying archaeal/bacterial community, while the second two processes are primarily conducted by phytoplankton. The overlapping spatial habitats and substrate requirements for these microbes …


Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro Jan 2021

Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro

Graduate Student Theses, Dissertations, & Professional Papers

Human activities have doubled the rate of nitrogen inputs onto the landscape resulting in elevated nitrogen concentrations in our streams. Anthropogenically applied nitrogen is largely transported to stream networks via groundwater movement. Groundwater discharge occurs in distinct points along a stream but whose influences can often persist far beyond that area due to insufficient biogeochemical removal of imported nitrogen potentially causing alterations in community structure and precipitating large algae blooms. To understand the factors governing nitrogen abundance in a historical polluted stream, I used a mass-balance approach to quantify groundwater-surface water interaction and the magnitude of groundwater nitrogen input and …


Field And Numerical Evaluation Of Nitrogen Transport From Septic Systems In Surfical Aquifer Systems To Charlotte Harbor, Florida, Tanten T. Buszka Apr 2020

Field And Numerical Evaluation Of Nitrogen Transport From Septic Systems In Surfical Aquifer Systems To Charlotte Harbor, Florida, Tanten T. Buszka

Masters Theses

Shallow water tables in coastal surficial aquifers limit effective treatment of septic effluent which can result in excess nutrient loading into nearby surface water bodies. Approximately 45,000 septic systems in Charlotte County, Florida transmit effluent into an under studied surficial aquifer and contribute to harmful algal blooms and outbreaks of E. coli. An undeveloped field site was characterized using standard hydrogeologic methods, including a one-year duration natural gradient tracer test, to obtain representative lithology of the sandy surficial aquifer and estimates of groundwater velocity, flow directions, effective porosity and dispersion. These data were used to support the development of a …


Improved Estimates Of Tributary Nitrogen Load To Casco Bay, Maine, Whitley J. Gray Aug 2019

Improved Estimates Of Tributary Nitrogen Load To Casco Bay, Maine, Whitley J. Gray

Electronic Theses and Dissertations

Over the past two decades, total nitrogen (TN) concentrations have increased in Casco Bay (CBEP 2015). The sources of the increased nitrogen are poorly understood but occur with simultaneous population growth and land use changes. The total riverine nitrogen load to Casco Bay was previously estimated by Liebman and Milstead (2012) using the United States Geologic Survey’s (USGS) SPAtially Referenced Regression On Watershed attributes (SPARROW) model. The SPARROW model uses watershed characteristics, regional monitoring data and nitrogen source data to estimate nitrogen loading but was not validated using measurements of nitrogen in the Casco Bay watershed. This study attempts to …


Nitrogen And Phosphorus Uptake In An Urban Stream Ecosystem, Nicolette A. Sheffield Mar 2019

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 …


Nutrient Transport And Storage In A Karst Spring-Reservoir System During Baseflow, Missouri Ozarks, Heather A. Moule Aug 2018

Nutrient Transport And Storage In A Karst Spring-Reservoir System During Baseflow, Missouri Ozarks, Heather A. Moule

MSU Graduate Theses

Urban and agricultural land uses are important sources of nitrogen and phosphorus which, if in excess, can cause eutrophication in lakes and rivers. There have been few studies of nutrient transport and storage in karst spring and reservoir connected stream systems draining the Missouri Ozarks. This study aims to link the baseflow nutrient contributions of Sanders Spring to downstream reservoir outflow and the Headwaters South Dry Sac River Watershed in Springfield, Missouri. Water samples were collected seasonally and analyzed for total nitrogen (TN), total phosphorus (TP), and several other water quality parameters. Discharge was also monitored to calculate water and …


Expansion Of The Manage Database With Forest And Drainage Studies, Daren R. Harmel, Laura E. Christianson, Matthew W. Mcbroom, Douglas R. Smith, Kori D. Higgs Jan 2016

Expansion Of The Manage Database With Forest And Drainage Studies, Daren R. Harmel, Laura E. Christianson, Matthew W. Mcbroom, Douglas R. Smith, Kori D. Higgs

Faculty Publications

The “Measured Annual Nutrient loads from AGricultural Environments” (MANAGE) database was published in 2006 to expand an early 1980s compilation of nutrient export (load) data from cultivated and pasture/range land at the field or farm scale. Then in 2008, MANAGE was updated with 15 additional studies, and nitrogen (N) and phosphorus (P) concentrations in runoff were added. Since then, MANAGE has undergone significant expansion adding N and P water quality along with relevant management and site characteristic data from: (1) 30 runoff studies from forested land uses, (2) 91 drainage water quality studies from drained land, and (3) 12 additional …


Evidence Of Late Quaternary Fires From Charcoal And Siliceous Aggregates In Lake Sediments In The Eastern U.S.A., Joanne P. Ballard Aug 2015

Evidence Of Late Quaternary Fires From Charcoal And Siliceous Aggregates In Lake Sediments In The Eastern U.S.A., Joanne P. Ballard

Doctoral Dissertations

The late-glacial transition to the Holocene, 15,000–11,600 cal yr BP, is an enigmatic period of dynamic global changes and a major extinction event in North America. Fire is an agent of disturbance that transforms the environment physically and chemically, and affects plant community composition. To improve understanding of the linkages between fire, vegetation, and climate over the late glacial and Holocene in the eastern U.S., I analyzed lake-sediment cores for charcoal and indicators of wood ash, and compared results to existing pollen records. A new microscopic charcoal record from Anderson Pond, Tennessee revealed high fire activity from 23,000–15,000 cal yr …


Water Quality Effects Of Cellulosic Biofuel Crops Grown On Marginal Land, Ruoyu Wang Jul 2014

Water Quality Effects Of Cellulosic Biofuel Crops Grown On Marginal Land, Ruoyu Wang

Ruoyu Wang

Since Congress' Energy Independence and Security Act of 2007, there has been increasing interest
in the ability to reach the cellulosic renewable fuel goal of 60.5 billion liters. Cellulosic biofuel crops include
sorghum, switchgrass, Miscanthus, woody crops, and crop residue, among others. Because of concern about
food production on existing highly productive agricultural lands, there is an interest regarding biofuel crop
production on marginal lands. Second generation biofuels, such as perennial grasses and woody plants,
provide an alternative to traditional crops; however, their effects on water quality are not well studied when
grown on marginal lands. Because grasses and woody …


Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker May 2014

Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker

2014 Student Theses

Over three million people call Long Island their home. With access to beautiful landscapes, world-renowned beaches, and proximity to New York City, it is no wonder that so many proudly call this geographic stretch of glacial till their home. However, throughout the years our actions do not necessarily reflect this affection we have to our home. Years of sprawl and human infestation across the island have resulted in widespread environmental degradation. Specifically, the water we drink and the beaches we enjoy have become endangered. I plan on studying the urban ecology of how intensified population growth led to the eutrophication …


Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu Dec 2012

Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu

Electronic Thesis and Dissertation Repository

This dissertation explored topographic controls on spatial and temporal patterns in water yield and nutrient (carbon, nitrogen and phosphorus) export from forested headwater catchments in the Turkey Lakes Watershed in central Ontario, where other factors contributing to differences in water yield and nutrient export, including climate, geology, forest, and soils, are relatively constant. Topographic characteristics, including (a) hydrological flushing potential (expansion of water table into nitrate-N producing areas); (b) hydrological storage potential (area of wetlands, which can alternatively allow water and nutrients to bypass wetlands when storage capacity is filled with water or to trap them when not filled); and …


Something Is Askew In Florida's Water: Arguing For A Better Descriptive Statistic For Positively Skewed Water-Quality Data, Amie October West Jan 2012

Something Is Askew In Florida's Water: Arguing For A Better Descriptive Statistic For Positively Skewed Water-Quality Data, Amie October West

USF Tampa Graduate Theses and Dissertations

ABSTRACT

It may be of no surprise that water quality data is right-skewed, but what appears to be overlooked by some is that the arithmetic mean and standard deviation most often fail as measures of central tendency in skewed data. When using the arithmetic mean and arithmetic standard deviation with nutrient data, one standard deviation about the arithmetic mean can capture nearly all of the data and extend into negative values. Representing nutrient data this way can be misleading to viewers who are using the statistics, and making assumptions, to understand the characteristics of those waters. Through an in-depth statistical …


The Influence Of Nutrients And Physical Habitat In Regulating Algal Biomass In Agricultural Streams, Mark D. Munn, Jeffrey Frey, Anthony Tesoriero Jan 2010

The Influence Of Nutrients And Physical Habitat In Regulating Algal Biomass In Agricultural Streams, Mark D. Munn, Jeffrey Frey, Anthony Tesoriero

United States Geological Survey: Water Reports and Publications

This study examined the relative influence of nutrients (nitrogen and phosphorus) and habitat on algal biomass in five agricultural regions of the United States. Sites were selected to capture a range of nutrient conditions, with 136 sites distributed over five study areas. Samples were collected in either 2003 or 2004, and analyzed for nutrients (nitrogen and phosphorous) and algal biomass (chlorophyll a). Chlorophyll a was measured in three types of samples, fine-grained benthic material (CHLFG), coarse-grained stable substrate as in rock or wood (CHLCG), and water column (CHLS). Stream and riparian habitat were characterized at each site. TP ranged from …


Sheep Updates 2007 - Part 3, Andrew Ritchie, Edward Riggall, James Hall, Gus Rose, Johan Greeff, John Young, M. Alchin, M. Young, T. Johnson, John Lucy, Martin Staines, Tim Wiley, Rob Grima, Sandra Prosser, Matt Ryan, Geoff Moore, Tony Albertsen, Phil Barrett-Lennard, George Woolston, John Titerington, Sarah Knight, Brianna Peake Jul 2007

Sheep Updates 2007 - Part 3, Andrew Ritchie, Edward Riggall, James Hall, Gus Rose, Johan Greeff, John Young, M. Alchin, M. Young, T. Johnson, John Lucy, Martin Staines, Tim Wiley, Rob Grima, Sandra Prosser, Matt Ryan, Geoff Moore, Tony Albertsen, Phil Barrett-Lennard, George Woolston, John Titerington, Sarah Knight, Brianna Peake

Sheep Updates

This session covers seven papers from different authors:

PROFITABILITY

1. Benchmarking demonstrates both the potential and realised productivity gains in the sheep and wool industry, Andrew Ritchie, Edward Riggall and James Hall, ICON Agriculture, Darkan

2. Improving sheep genetics will increase farm profitability, Gus Rose, Johan Greeff Department of Agriculture and Food Western Australia, John Young Farming Systems Analysis Service, WA

3. Meat, Merinos and making money in WA Pastoral Zone, M. Alchin, M. Young and T. Johnson, Department of Agriculture and Food Western Australia,

GRAZING

4. Nitrogen - farmers' friend or foe? John Lucy and Martin Staines, Department …


Crop Updates 2007 - Farming Systems, David Jeffries, A. Loi, B. J. Nutt, C. K. Revell, Yvette Oliver, Michael Robertson, Bill Bowden, Kit Leake, Ashley Bonser, Ian Maling, Bindi Isbister, Garren Knell, Alison Slade, David Stephens, Michael Meuleners, David Beard, Nicolyn Short, Rob Grima, Ingrid Richardson, Ruhi Ferdowsian, Geoff Bee, David Evans, Bob Gilkes, Senthold Asseng, Jim Dixon, Felicity Byrne, Mike Ewing, Dennis Van Gool, Louise Barton, Ralf Kiese, David Gatter, Klaus Butterbach-Bahl, Renee Buck, Christoph Hinz, Daniel Murphy, Cameron Weeks, Meredith Fairbanks, John Peirce, Brad Rayner, Sandy White, Paul Damon, Qifa Ma, Zed Rengel, Ed Barrett-Lennard, Meir Altman, Tracey M. Gianatti, Lindsay Bell, Ben Webb, Caroline Peek, Paul Sanford, Paul Blackwell, Glen Riethmuller, Darshan Sharma, Mike Collins, Frank D'Emden, David Hall, G. P. Manango, D. L. Steverson, Vanessa Stewart, Julie Roche, Peter Rutherford, Imma Farré, Ian Foster, Stephen Charles, Frances Hoyle, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Rob Sands, David Mccarthy, Paul Carmody, J. Russell, J. Eyres, G. Fosbery, A. Roe, Phil Nichols, Andrew Bathgate, Anne Wilkins Feb 2007

Crop Updates 2007 - Farming Systems, David Jeffries, A. Loi, B. J. Nutt, C. K. Revell, Yvette Oliver, Michael Robertson, Bill Bowden, Kit Leake, Ashley Bonser, Ian Maling, Bindi Isbister, Garren Knell, Alison Slade, David Stephens, Michael Meuleners, David Beard, Nicolyn Short, Rob Grima, Ingrid Richardson, Ruhi Ferdowsian, Geoff Bee, David Evans, Bob Gilkes, Senthold Asseng, Jim Dixon, Felicity Byrne, Mike Ewing, Dennis Van Gool, Louise Barton, Ralf Kiese, David Gatter, Klaus Butterbach-Bahl, Renee Buck, Christoph Hinz, Daniel Murphy, Cameron Weeks, Meredith Fairbanks, John Peirce, Brad Rayner, Sandy White, Paul Damon, Qifa Ma, Zed Rengel, Ed Barrett-Lennard, Meir Altman, Tracey M. Gianatti, Lindsay Bell, Ben Webb, Caroline Peek, Paul Sanford, Paul Blackwell, Glen Riethmuller, Darshan Sharma, Mike Collins, Frank D'Emden, David Hall, G. P. Manango, D. L. Steverson, Vanessa Stewart, Julie Roche, Peter Rutherford, Imma Farré, Ian Foster, Stephen Charles, Frances Hoyle, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Rob Sands, David Mccarthy, Paul Carmody, J. Russell, J. Eyres, G. Fosbery, A. Roe, Phil Nichols, Andrew Bathgate, Anne Wilkins

Crop Updates

This session covers forty papers from different authors:

1. Quality Assurance and industry stewardship, David Jeffries, Better Farm IQ Manager, Cooperative Bulk Handling

2. Sothis: Trifolium dasyurum (Eastern Star clover), A. Loi, B.J. Nutt and C.K. Revell, Department of Agriculture and Food

3. Poor performing patches of the paddock – to ameliorate or live with low yield? Yvette Oliver1, Michael Robertson1, Bill Bowden2, Kit Leake3and Ashley Bonser3, CSIRO Sustainable Ecosystems1, Department of Food and Agriculture2, Kellerberrin Farmer3

4. What evidence is there that …


Impact Of More Intensive Grazing On Nitrogen And Phosphorus In Shallow Aquifers Of The Southern Perth Basin, D L. Bennett, Patrick Donnelly, Peter J. Tille Jan 2007

Impact Of More Intensive Grazing On Nitrogen And Phosphorus In Shallow Aquifers Of The Southern Perth Basin, D L. Bennett, Patrick Donnelly, Peter J. Tille

Resource management technical reports

This study reports on the nutrient content, pH and salinity of groundwater samples collected from the watertable and within the Superficial and the upper Leederville Aquifers from the Southern Perth Basin, south of Pinjarra, Western Australia. Sampling was undertaken to determine the impact of intensification of broadscale grazing on groundwater nutrients in the area.


Consequences Of Reservoir Drainage On Downstream Water Chemistry, Suspended Sediment, And Nutrients, Southwest Missouri, Mark W. Bowen Jan 2004

Consequences Of Reservoir Drainage On Downstream Water Chemistry, Suspended Sediment, And Nutrients, Southwest Missouri, Mark W. Bowen

MSU Graduate Theses

Construction and subsequent draining of reservoirs can have dramatic affects on the release of nutrients and sediments to waterways. This study describes how the temporary draining of a small reservoir for dam repair influences downstream water quality. The Valley Mill Reservoir has a surface area of 6.1 hectares and volume of 150,000 m3 when filled. Water chemistry monitoring and water sampling were performed at six sites during baseflow and ten sites during runoff events for one year. Water samples were analyzed for total nitrogen (TN), total phosphorous (TP), and total suspended sediment (TSS) concentrations. Results indicate that draining of Valley …


Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale Jun 1988

Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale

Technical Reports

In Arkansas, approximately 1 Tg of poultry (Gallus gallus domesticus) manure and litter is produced annually. These waste products are commonly applied to pastures as a soil amendment or fertilizer, but excessive application rates and poor management practices could result in nutrient contamination of ground and surface water. The purpose of this study was to: (1) assess the nutrient concentrations in poultry manure and (2) evaluate the nitrogen loss from land-applied poultry litter and manure due to ammonia volatilization and denitrification. Analyses for total Kjeldahl nitrogen (TKN), inorganic nitrogen (Ni), phosphorus (P), and potassium (K) were compared in 12 wet …


Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale Jun 1987

Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale

Technical Reports

In 1985, more than 750 million broiler chickens were produced in Arkansas. During the same year over 15 million laying chickens produced 3.6 million eggs. The waste products of these agricultural production systems, poultry litter and manure, were about 1 million metric tons. As a result of land application of these wastes, about 5,000 metric tons of annnonium N and 12,000 metric tons of mineralized nitrogen were applied to Arkansas pastures in 1985. Manures contributed about 2-3 percent of the total. The objective of this research was to quantify major components of the nitrogen cycle which influence the ground and …


Concentration Of Nitrate-Nitrogen In Groundwater Central Platte Region, Nebrask 1984, M. E. Exner Jan 1985

Concentration Of Nitrate-Nitrogen In Groundwater Central Platte Region, Nebrask 1984, M. E. Exner

Conservation and Survey Division

No abstract provided.