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Environmental Monitoring

Nitrogen

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Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Indianapolis Waterways For Evidence Of Eutrophication And Contamination Induced By Urban Pollution, Kiley Grace Wardwell May 2022

Analysis Of Indianapolis Waterways For Evidence Of Eutrophication And Contamination Induced By Urban Pollution, Kiley Grace Wardwell

Undergraduate Honors Thesis Collection

The focus of my research will be largely focused on the water quality of the White River throughout Indianapolis. I will be testing water samples from five different points along the White River to analyze three of its contents, assessing the differing levels of pollution along different points progressing down the river and through the city. The locations I have chosen to test coincide with water gauge sites along the White River and are as follows: Logan Street in Noblesville, 82nd Street, Broad Ripple Dam, Michigan Road and Raymond Street. The surface water at these five locations will be tested …


Connecticut Embayment Characteristics 2022, Jamie M.P. Vaudrey, James E. O'Donnell Mar 2022

Connecticut Embayment Characteristics 2022, Jamie M.P. Vaudrey, James E. O'Donnell

Department of Marine Sciences

Data on Connecticut embayment characteristics. This Excel file is the centerpiece for capturing embayment characteristics as presented in RESPEC (2022), developed specifically for this project. Some parameters such as watershed size, embayment size, and tidal range were pulled from other sources described in Appendix A of RESPEC (2022), but much of the data and indicators in the Excel file were developed for this project. Each parameter included in the spreadsheet is fully defined in Appendix A of RESPEC (2022). All data available in the spreadsheet are provided by embayment in Appendix C of RESPEC (2022), including the results of bathymetric …


Quantifying The Leaching Of Nutrients And Metals In A Pasture Soil As Affected By Excreta Of Ruminants Fed Alternative Diets, Ian Kennedy May 2021

Quantifying The Leaching Of Nutrients And Metals In A Pasture Soil As Affected By Excreta Of Ruminants Fed Alternative Diets, Ian Kennedy

Graduate Theses and Dissertations

The leaching of nitrate through the soil profile and into adjacent water systems has been a leading cause of water pollution and results in the loss of a valuable nutrient from animal production systems. Forage-based animal production systems may be improved through manipulation of animal diets that incorporate tannins and total polyphenolic compounds with feed, increasing the amount of nitrogen (N) retained by an animal/decreasing rates of digestion and altering the N-containing compounds that are excreted and deposited onto soil. Incorporating the forage legumes sericea lespedeza (Lespedeza cuneate [Dumont de Courset] G. Don) and lablab (Lablab purpurues L.) into the …


Long Term Nutrient And Chlorophyll A Dynamics Across Long Island Sound And Impacts On Dissolved Oxygen Conditions Within The Western Sound (1991-2019), Sherry Perreira Jan 2021

Long Term Nutrient And Chlorophyll A Dynamics Across Long Island Sound And Impacts On Dissolved Oxygen Conditions Within The Western Sound (1991-2019), Sherry Perreira

Dissertations and Theses

Nitrogen overload, eutrophication, and hypoxia have been challenging and persistent water quality problems in Long Island Sound (LIS) over the past decades with major impacts on commercial industries, ecology, and recreational activities in the region. Recognizing these problems, the EPA enforced three phases of the Clean Water Act (CWA) to reduce nitrogen loads in an effort to improve this important estuary. This study examines how nitrogen (NH3, NOx & TDN), chlorophyll a (CHLA), and dissolved oxygen (DO) concentrations changed in LIS over the past 30 years, in response to water quality regulations as well as changes in …


Spatial And Temporal Variation Of Nutrients In The Great Lakes-St. Lawrence Basin: Implications For Primary Production In Stream Ecosystems, Nolan Pearce Aug 2020

Spatial And Temporal Variation Of Nutrients In The Great Lakes-St. Lawrence Basin: Implications For Primary Production In Stream Ecosystems, Nolan Pearce

Electronic Thesis and Dissertation Repository

Growing human populations and associated land use activities has increased the amount of nutrients delivered to surface waters. Eutrophication from the over-enrichment of nitrogen and phosphorus has degraded ecosystem conditions in streams, lakes, and coastal areas worldwide. Thus, the management of anthropogenic nutrient loading is a global concern. This thesis employed a combination of field and experimental research to provide watershed managers with information on the spatial and temporal patterns in stream nutrient enrichment, and the associated ecological effects of anthropogenic nutrient loading in the Great Lakes-St. Lawrence basin. Four studies were completed to address this research goal. First, I …


In Situ Plant Uptake Of Excess Nutrients And Consequential Alteration Of Rhizosphere Dynamics, Srusti Maddala May 2020

In Situ Plant Uptake Of Excess Nutrients And Consequential Alteration Of Rhizosphere Dynamics, Srusti Maddala

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The use of phytoremediation in ecological remediation projects has numerous benefits including soil stabilization and nutrient uptake. Recently, microdialysis, a diffusion-based sampling technique commonly used in biomedical research, has been recognized as a candidate for monitoring chemical changes in the rhizosphere. The real-time, in situ data it provides about nutrient diffusion may improve the management and success of restoration projects. Therefore, the objective of this study was to employ the technique of microdialysis in the novel application of quantifying the diffusive flux of inorganic nitrogen compounds in the rhizosphere of native plants of Arkansas. The microdialysis technique was first optimized …


Impacts Of Human Recreation On Nutrient Availability And Periphyton Abundance On The Niobrara River, Matthew Chen, Jessica Corman, Sydney Kimnach, Kayla Vondracek Apr 2020

Impacts Of Human Recreation On Nutrient Availability And Periphyton Abundance On The Niobrara River, Matthew Chen, Jessica Corman, Sydney Kimnach, Kayla Vondracek

UCARE Research Products

In freshwater ecosystems, eutrophication can create many problems. Excess nutrients, like nitrogen or phosphorus, promote algal or cyanobacterial growth. This growth also leads to increased organic matter production and decomposition, a process that can reduce oxygen concentration in the water. When this happens, species diversity declines, transparency of the water declines, and anoxia may lead to fish kills . Of particular concern is the possibility of cyanobacteria blooms that create compounds toxic for humans. Many of the waters across Nebraska receive excessive nutrients from human activities, largely related to agriculture (Dickey 1982). However, there is one river, the Niobrara River, …


Microdialysis: A Method For Quantifying In Situ Nitrogen Fluxes In Soil Microsites, Srusti Maddala, Mary C. Savin, Julie A. Stenken, Lisa S. Wood Jan 2020

Microdialysis: A Method For Quantifying In Situ Nitrogen Fluxes In Soil Microsites, Srusti Maddala, Mary C. Savin, Julie A. Stenken, Lisa S. Wood

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

Microdialysis, a diffusion-based sampling technique commonly used in biomedical research, has recently been recognized as a candidate for monitoring chemical changes in the rhizosphere. The information it provides about nutrient diffusion may improve nitrogen use efficiency, leading to enhanced management and success of restoration projects. The objective of this study was to determine the efficacy of microdialysis sampling to quantify the relative recoveries (RR%) of nitrate-N and ammonium-N, the two inorganic nitrogen compounds typically found in soil. The effects of microdialysis flow rate, sample medium concentration, and the presence of both analytes in solution on the relative recoveries obtained from …


Defoliation Severity Is Positively Related To Soil Solution Nitrogen Availability And Negatively Related To Soil Nitrogen Concentrations Following A Multi-Year Invasive Insect Irruption, Emma Conrad-Rooney, Audrey Barker Plotkin, Valerie J. Pasquarella, Joseph Elkinton, Jennifer L. Chandler, Jaclyn Hatala Matthes Jan 2020

Defoliation Severity Is Positively Related To Soil Solution Nitrogen Availability And Negatively Related To Soil Nitrogen Concentrations Following A Multi-Year Invasive Insect Irruption, Emma Conrad-Rooney, Audrey Barker Plotkin, Valerie J. Pasquarella, Joseph Elkinton, Jennifer L. Chandler, Jaclyn Hatala Matthes

Environmental Conservation Faculty Publication Series

Understanding connections between ecosystem nitrogen (N) cycling and invasive insect defoliation could facilitate the prediction of disturbance impacts across a range of spatial scales. In this study we investigated relationships between ecosystem N cycling and tree defoliation during a recent 2015–18 irruption of invasive gypsy moth caterpillars (Lymantria dispar), which can cause tree stress and sometimes mortality following multiple years of defoliation. Nitrogen is a critical nutrient that limits the growth of caterpillars and plants in temperate forests. In this study, we assessed the associations among N concentrations, soil solution N availability and defoliation intensity by L. dispar …


Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio Dec 2019

Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

A nitrogen (N) balance, calculated as the difference between N inputs and grain-N removal, provides an estimate of the potential N losses. We used N balance with other N-related metrics (partial factor productivity for N inputs, and yield-scaled N balance), to benchmark maize yields in relation with N input use in the US Corn Belt. We first used experimental data on grain-N concentration (GNC) to assess variation in this parameter due to biophysical and management factors. Subsequently, we used N balance and N-related metrics to benchmark yields in relation with N inputs in irrigated and rainfed fields in Nebraska using …


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 …


Dissolved Inorganic Nitrogen Dynamics In Swash Zone Sands Of Long Bay, Sc, Alexis F. Echols Apr 2019

Dissolved Inorganic Nitrogen Dynamics In Swash Zone Sands Of Long Bay, Sc, Alexis F. Echols

Honors Theses

A key component affecting the biogeochemistry of the sedimentary environment is pore water between grains of sediments. Sedimentary microorganisms are constantly modifying chemical compounds as part of their life functions which are then exchanged between the sediment column and the overlying water column. Dissolved inorganic nitrogen, a major element for life, takes on several forms including nitrate, nitrite, and ammonium which vary in concentration throughout the sediment and with respect to each other. The relative concentrations of these nitrogen species have been previously briefly explored in sandy columns, where redox gradients that control their relative concentrations can be fairly deep …


Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe Dec 2018

Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe

United States Environmental Protection Agency: Staff Publications

We constructed a seasonal nitrogen (N) budget for the year 2008 in the Calapooia River Watershed (CRW), an agriculturally dominated tributary of the Willamette River (Oregon, U.S.) under Mediterranean climate. Synthetic fertilizer application to agricultural land (dominated by grass seed crops) was the source of 90% of total N input to the CRW. Over 70% of the stream N export occurred during the wet winter, the primary time of fertilization and precipitation, and the lowest export occurred in the dry summer. Averaging across all 58 tributary subwatersheds, 19% of annual N inputs were exported by streams, and 41% by crop …


Ulva Spp. Bloom Dynamics In A Hyper-Eutrophic Estuary: Jamaica Bay, New York, Annesia Lamb Sep 2018

Ulva Spp. Bloom Dynamics In A Hyper-Eutrophic Estuary: Jamaica Bay, New York, Annesia Lamb

Dissertations, Theses, and Capstone Projects

In this dissertation, I present three studies that further our understanding of macroalgae identity, growth, and proliferation. Eutrophication is prevalent in shallow coastal ecosystems world-wide. One of the ecosystem consequences is the development of a bloom forming green marine macroalgae, Ulva spp. Ulva can have negative effects such as Zostera spp. degradation, fish, and shellfish declines. I performed assessments of (1) identity of the bloom-forming Ulva and other macroalgae assemblage, (2) physical, chemical, and biological drivers of Ulva bloom growth and proliferation, and (3) optimal irradiance and temperature requirements for early growth stages in Ulva linza.

The first study …


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 …


Effects Of Enhanced Efficiency Nitrogen Fertilizers On Agronomic Parameters And Loss Pathways In The Subtropical Mississippi Delta Region, Scott Michael Pensky Apr 2018

Effects Of Enhanced Efficiency Nitrogen Fertilizers On Agronomic Parameters And Loss Pathways In The Subtropical Mississippi Delta Region, Scott Michael Pensky

LSU Master's Theses

Minimizing nitrogen (N) loss is critical for improving N use efficiency (NUE) in crop production and reducing its effects on the environment. Management practices such as seasonal application timing of N fertilizers and the addition of enhanced efficiency N fertilizers (EENFs) were investigated for the high N requirement of the two most common cereal crops globally, corn (Zea mays L.) and wheat (Triticum aestivum L.), in the subtropical climate of Louisiana. Field research was established during the 2016 and 2017 seasons at the LSU Agricultural Center’s Dean Lee and Central research stations to examine the effect of different EENFs and …


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 Nov 2017

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 …


A Novel Method For Determination Of Ammonium Isotope Ratios With Electrospray Ionization Mass Spectrometry, Rebecca J. Chmiel Jan 2017

A Novel Method For Determination Of Ammonium Isotope Ratios With Electrospray Ionization Mass Spectrometry, Rebecca J. Chmiel

Honors Theses

Nitrogen (15N) isotope tracer studies are an invaluable tool for understanding the rate of N transformations in the environment. A mechanistic understanding of N cycling is critical to management of excess N availability in freshwater and marine ecosystems. Conventional methods for measuring 15N:14N of dissolved inorganic nitrogen species are time consuming and require large sample volumes. Here, we present a technique for measuring 15N:14N in ammonium (NH4+) using electrospray ionization mass spectrometry (ESI-MS). NH4+ present in small volumes of sample (3 ml) is complexed with phenol via …


Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker May 2014

Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker

Graduate Theses and Dissertations

Nitrogen (N2) fixation can give certain species of cyanobacteria a competitive advantage in lake and reservoir phytoplankton. These species of cyanobacteria, along with others that cannot fix N2, can form toxic compounds that impair water quality when present in high concentrations. N2 fixation rates may be substantial in small (< 1.0 km2), temperate reservoirs since these systems experience thermal stratification and often nitrogen (N) limitation throughout a substantial proportion of the year. However, the effects of N2 fixation on N cycling, alleviation of short-term N limitation, and water quality are not well-understood. A mesocosm experiment and ecosystem-scale observational study were conducted to 1) determine the efficiency of N2 fixation under varying N relative to phosphorus (P) supply, 2) examine the effects of N2 fixation on autotrophic biomass accumulation and microcystin production, and 3) measure N2 fixation rates and importance to autotrophic N demand and zooplankton N assimilation. Results of the mesocosm experiment indicated that N2 fixation was increased at low N:P supply under high P. However, N2 fixation was inefficient at alleviating N limitation when fixed N was the primary source of N. Additionally, microcystin production occurred only at high N:P supply when N2 fixation was low, indicating that reducing external N inputs may have a positive effect on water quality. Results of whole-reservoir determination of N2 fixation using seston δ15N natural abundances indicated that N2 fixation rates throughout the warm season were substantial and influenced by water temperature. Annual N2 fixation rates ranged from 2.2 - 6.6 g N m-2 yr-1, and contributed up to 19% of the annual autotrophic N demand. Zooplankton were assimilating fixed N in most of the study reservoirs, representing a possible mechanism of ecosystem fixed N retention. Collectively, these results suggest that N2 fixation plays a substantial role in N cycling in small, temperate reservoirs, but likely cannot alleviate short-term N limitation.


The Impact Of Dams On Nitrogen Cycling In The Messalonskee Stream, Rebecca K. Forgrave Jan 2014

The Impact Of Dams On Nitrogen Cycling In The Messalonskee Stream, Rebecca K. Forgrave

Honors Theses

The Messalonskee Stream in central Maine has five hydroelectric dams on 16.6km. Each dam drastically changes the flow regime of the stream, dividing it into segments with different patterns of sediment settling and organic matter retention. I investigated how these disruptions impact nitrogen cycling, specifically nitrification rates above and below each dam. I expected higher nitrification rates above the dams, where levels of organic matter are higher, and lower rates below the dam where scouring removes organic matter and fine sediment from the streambed. I measured sediment nitrification rates with a nitrapyrin-inhibition assay and potential drivers of nitrification including sediment …


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 …


The Fate Of Nitrogren Fixed By Diazotrophs In The Ocean, Margaret R. Mulholland Jan 2007

The Fate Of Nitrogren Fixed By Diazotrophs In The Ocean, Margaret R. Mulholland

OES Faculty Publications

While we now know that N2 fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this N (and associated C), despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does N fixed during N2 fixation fuel autotrophic or heterotrophic growth and thus facilitate carbon (C) export from the euphotic zone, or does it contribute primarily to bacterial productivity and respiration in the euphotic zone? For Trichodesmium, the diazotroph we know the most about, the transfer of recently fixed N2 (and C) appears …


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.


Crop Updates 2005 - Farming Systems, David Stephens, Nicola Telcik, Ross Kingwell, Wayne Pluske, Bill Bowden, Mike Collins, Frances Hoyle, D. V. Murphy, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Bill Crabtree, Geoff Anderson, Darren Kidson, Ross Brennan, Nick Drew, Craig Scanlan, Lisa Sherriff, Bob French, Reg Lunt, Jeff Russell, Angie Roe, Ian Maling, Matthew Adams, George Yan, Mohammad Hamza, Glen Riethmuller, Wal Anderson, Angela Loi, Phil Nichols, Clinton Revell, David Ferris, Phil Ward, Andrea Hills, Sally-Anne Penny, David Hall, Michael Robertson, Don Gaydon, Tress Walmsley, Caroline Peek, Megan Abrahams, Paul Raper, Richard O'Donnell, Trevor Lacey, Meredith Fairbanks, David Tennant, Cameron Weeks, Richard Quinlan, Alexandra Edward, Chris Carter, Doug Hamilton, Peter Tozer, Renaye Horne, Tracey Gianatti, Paul Carmody, Ian Foster, Michele John, Ross George, Imma Farré, Ian Kininmonth, Dennis Van Gool, Neil Coles, Bill Porter, Louise Barton, Richard Harper, Peter Ritson, Tony Beck, Chris Mitchell, Michael Hill, Fiona Barker-Reid, Will Gates, Ken Wilson, Rob Baigent, Ian Galbally, Mick Meyer, Ian Weeks, Traci Griffin, D. Rodriguez, M. Probust, M. Meyers, D. Chen, A. Bennett, W. Strong, R. Nussey, I Galbally, M. Howden Feb 2005

Crop Updates 2005 - Farming Systems, David Stephens, Nicola Telcik, Ross Kingwell, Wayne Pluske, Bill Bowden, Mike Collins, Frances Hoyle, D. V. Murphy, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Bill Crabtree, Geoff Anderson, Darren Kidson, Ross Brennan, Nick Drew, Craig Scanlan, Lisa Sherriff, Bob French, Reg Lunt, Jeff Russell, Angie Roe, Ian Maling, Matthew Adams, George Yan, Mohammad Hamza, Glen Riethmuller, Wal Anderson, Angela Loi, Phil Nichols, Clinton Revell, David Ferris, Phil Ward, Andrea Hills, Sally-Anne Penny, David Hall, Michael Robertson, Don Gaydon, Tress Walmsley, Caroline Peek, Megan Abrahams, Paul Raper, Richard O'Donnell, Trevor Lacey, Meredith Fairbanks, David Tennant, Cameron Weeks, Richard Quinlan, Alexandra Edward, Chris Carter, Doug Hamilton, Peter Tozer, Renaye Horne, Tracey Gianatti, Paul Carmody, Ian Foster, Michele John, Ross George, Imma Farré, Ian Kininmonth, Dennis Van Gool, Neil Coles, Bill Porter, Louise Barton, Richard Harper, Peter Ritson, Tony Beck, Chris Mitchell, Michael Hill, Fiona Barker-Reid, Will Gates, Ken Wilson, Rob Baigent, Ian Galbally, Mick Meyer, Ian Weeks, Traci Griffin, D. Rodriguez, M. Probust, M. Meyers, D. Chen, A. Bennett, W. Strong, R. Nussey, I Galbally, M. Howden

Crop Updates

This session covers forty four papers from different authors:

PLENARY

1. 2005 Outlook, David Stephens and Nicola Telcik, Department of Agriculture

FERTILITY AND NUTRITION

2. The effect of higher nitrogen fertiliser prices on rotation and fertiliser strategies in cropping systems, Ross Kingwell, Department of Agriculture and University of Western Australia

3. Stubble management: The short and long term implications for crop nutrition and soil fertility, Wayne Pluske, Nutrient Management Systems and Bill Bowden, Department of Agriculture

4. Stubble management: The pros and cons of different methods, Bill Bowden, Department of Agriculture, Western Australia and Mike Collins, …


Lake Mead Cover Enhancement Project, Jennifer Stevens Haley, Suzanne Leavitt, Larry Paulson, Donald H. Baepler Jul 1987

Lake Mead Cover Enhancement Project, Jennifer Stevens Haley, Suzanne Leavitt, Larry Paulson, Donald H. Baepler

Publications (WR)

Ninety-three wildlife agencies were surveyed for information on their attempts to improve fish habitat. In addition, an annotated bibliography including over 100 summaries was completed on:

1. largemouth bass cover requirements and preferences,

2. use and effectiveness of artificial cover,

3. aquatic plant introduction and species requirements for germination and establishment,

4. terrestrial plant introduction and species requirements for germination and establishment, and

5. nutrient exchange between sediment, aquatic plants, and water.

A reconnaissance of existing terrestrial and aquatic vegetation was completed in June 1986 including the production of a video tape of the Nevada shoreline of Lake Mead.

Cover …


Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection May 1987

Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Rationale of review and for proposed changes to the Nevada Pollution Control Regulations (NAC 445.1354, 445.1355, 445.1356, 455.1367, 445.1352, 445.1353, 445.1350, 445.1351) before the State Environmental Commission on June 23 and 24, 1987.


Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan Jul 1981

Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan

Publications (WR)

The interstitial water chemistry of the sediments of Las Vegas Bay and Bonelli Bay in Lake Mead has been studied as part of a comprehensive water quality study of those locations. Pore water and solid phase analyses were completed from four stations in Las Vegas Bay and two stations in Bonelli Bay. At both locations the pore water compositions and organic matter diagenesis in the sediments are dominated by sulfate reduction. This major role of sulfate reduction is unusual for lake sediments and reflects the fact that SO4 is the major anion in the lake water. In addition, gypsum …