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Articles 631 - 660 of 1200

Full-Text Articles in Fresh Water Studies

Comparison Of Total Mercury And Methylmercury Cycling At Five Sites Using The Small Watershed Approach, James B. Shanley, M. Alisa Mast, Donald H. Campbell, George R. Aiken, David P. Krabbenhoft, Randall J. Hunt, John F. Walker, Paul F. Schuster, Ann Chalmers, Brent T. Aulenbach, Norman E. Peters, Mark Marvin-Dipasquale, David W. Clow, Martin M. Shafer Jan 2008

Comparison Of Total Mercury And Methylmercury Cycling At Five Sites Using The Small Watershed Approach, James B. Shanley, M. Alisa Mast, Donald H. Campbell, George R. Aiken, David P. Krabbenhoft, Randall J. Hunt, John F. Walker, Paul F. Schuster, Ann Chalmers, Brent T. Aulenbach, Norman E. Peters, Mark Marvin-Dipasquale, David W. Clow, Martin M. Shafer

United States Geological Survey: Staff Publications

The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L-1 and MeHg was less than 0.2 ng L-1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with …


Interagency Science And Research Strategy, Limnological Assistance For Lake Mead National Recreation Area Jan 2008

Interagency Science And Research Strategy, Limnological Assistance For Lake Mead National Recreation Area

Limnological Studies

Helping improve operational efficiency, enhance land stewardship, resource protection, and conservation on the shared public land.


Ecological Consequences Of Invasion Of The Quagga Mussel (Dreissena Bugensis Andrusov 1897) Into Lake Mead, David Wong, Shawn Gerstenberger, Todd Tietjen, Sara Ann Mueting, Eric Michael Loomis Jan 2008

Ecological Consequences Of Invasion Of The Quagga Mussel (Dreissena Bugensis Andrusov 1897) Into Lake Mead, David Wong, Shawn Gerstenberger, Todd Tietjen, Sara Ann Mueting, Eric Michael Loomis

Limnological Studies

Consequences of Invasion of the Quagga Mussel into Lake Mead


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: December 31, 2007, Margaret N. Rees Dec 2007

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: December 31, 2007, Margaret N. Rees

Limnological Studies

  • The limnologist position has been announced.
  • Project 1: Review of the draft Boulder Basin Adaptive Management Plan is underway.
  • Project 2: Development of a white paper expressing the joint needs of the entities involved in Water 2025 projects is being coordinated.
  • Project 3: A bibliographic reference spreadsheet organizing literature citations related to quagga and zebra mussel research has been completed.
  • Project 4: A comprehensive literature search of Lake Mead limnology is well underway; an Access database has been designed to organize reference citations; and a special collections library at UNLV is being established to house original rare documents and other …


Eutrophication In Farmington Bay And Its Potential Impacts On Wildlife, Wayne A. Wurtsbaugh Oct 2007

Eutrophication In Farmington Bay And Its Potential Impacts On Wildlife, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.


Soil Survey Of The Bettink Dairy Farm, Riverway Road, Northcliffe, Peter J. Tille, Tilwin Westrup Oct 2007

Soil Survey Of The Bettink Dairy Farm, Riverway Road, Northcliffe, Peter J. Tille, Tilwin Westrup

Resource management technical reports

This soil survey of the Bettink dairy farm in Northcliffe, Western Australia aimed to: provide detailed soil descriptions to add to information associated with the environment in which the dairy industry in Western Australia is located; collect soil samples at predetermined standard depths from documented farm locations for nutrient analysis; map soils with similar characteristics based on description and analysis.


Allagash Wilderness Waterway Working Group On Structure, Management And Oversight: Choosing Common Ground And Moving Ahead (Executive Summary), Allagash Wilderness Waterway Working Group Jan 2007

Allagash Wilderness Waterway Working Group On Structure, Management And Oversight: Choosing Common Ground And Moving Ahead (Executive Summary), Allagash Wilderness Waterway Working Group

Maine History & Policy Development

In his June 19, 2006, Executive Order, Governor John E. Baldacci directed the Working Group to “offer its best guidance and advice to the Governor respecting the long-term governance, management, and oversight structure for the Allagash Wilderness Waterway” (AWW). In the intervening six months the members of the Working Group have engaged in an examination of the forty-year history of the Waterway and an analysis of the conditions and circumstance that led to the Governor’s Executive Order. We have reviewed documentation of the AWW history, taken testimony at numerous public meetings and hearings, conducted correspondence with members of the several …


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.


Boyup Brook - Upper Warren Area : Catchment Appraisal 2007/ Prepared By The South West Arm Region Appraisal Team., Henry Brockman Jan 2007

Boyup Brook - Upper Warren Area : Catchment Appraisal 2007/ Prepared By The South West Arm Region Appraisal Team., Henry Brockman

Resource management technical reports

The aim of this Resource Management Technical Report is to assess the current extent of salinity and other natural resource degradation issues in the Boyup Brook - Upper Warren area and provide landholders with the best current management options to address natural resource management issues and enhance sustainable agricultural production.


Potential Capture Of Surface Run-Off For Reliable Water Supplies In The 500-825 Mm Rainfall Zone Of South Western Australia, D L. Bennett, Peter J. Tille, Ned Stephenson, Tilwin Westrup Jan 2007

Potential Capture Of Surface Run-Off For Reliable Water Supplies In The 500-825 Mm Rainfall Zone Of South Western Australia, D L. Bennett, Peter J. Tille, Ned Stephenson, Tilwin Westrup

Resource management technical reports

No abstract provided.


West Midlands Region Catchment Appraisal 2007, Angela Stuart-Street, Northern Agricultural Region Catchment Appraisal Team Jan 2007

West Midlands Region Catchment Appraisal 2007, Angela Stuart-Street, Northern Agricultural Region Catchment Appraisal Team

Resource management technical reports

Annual run-off likely to occur was calculated for farm-scale catchments within the 500-825 millimetre rainfall zone of the South West Catchment Council [Western Australia] area. When compared with historical flow measurements, this method was found to be accurate (or conservative) in 85% of all measured years, indicating its usefulness for predicting reliable annual flows.


Sulfur-Oxidizing Bacteria In Soap Lake (Washington State), A Meromictic, Haloalkaline Lake With An Unprecedented High Sulfide Content, Dimitry Y. Sorokin, Mirjam Foti, Holly C. Pinkart, Gerard Muyzer Jan 2007

Sulfur-Oxidizing Bacteria In Soap Lake (Washington State), A Meromictic, Haloalkaline Lake With An Unprecedented High Sulfide Content, Dimitry Y. Sorokin, Mirjam Foti, Holly C. Pinkart, Gerard Muyzer

All Faculty Scholarship for the College of the Sciences

Culture-dependent and -independent techniques were used to study the diversity of chemolithoautotrophic sulfur-oxidizing bacteria in Soap Lake (Washington State), a meromictic, haloalkaline lake containing an unprecedentedly high sulfide concentration in the anoxic monimolimnion. Both approaches revealed the dominance of bacteria belonging to the genus Thioalkalimicrobium, which are common inhabitants of soda lakes. A dense population of Thioalkalimicrobium (up to 107 cells/ml) was found at the chemocline, which is characterized by a steep oxygen-sulfide gradient. Twelve Thioalkalimicrobium strains exhibiting three different phenotypes were isolated in pure culture from various locations in Soap Lake. The isolates fell into two groups …


Comparison Of Aquatic-Insect Habitat And Diversity Above And Below Road Crossings In Low-Order Streams, J. Wesley Neal, Nathan J. Harris, Sathyanand Kumaran, David A. Behler, Thomas J. Lang, Paul R. Port, Marcella Melandri, Benjamin G. Batten Jan 2007

Comparison Of Aquatic-Insect Habitat And Diversity Above And Below Road Crossings In Low-Order Streams, J. Wesley Neal, Nathan J. Harris, Sathyanand Kumaran, David A. Behler, Thomas J. Lang, Paul R. Port, Marcella Melandri, Benjamin G. Batten

Journal of the Arkansas Academy of Science

The effects of road crossings on fish communities have been extensively studied; yet little attention has been given to macroinvertebrate communities. This study evaluated physical stream characteristics, water quality, and aquatic-insect richness from above and below road crossings of low-order streams in the Ouachita National Forest in Arkansas. Fifteen road crossings were sampled during October and November 2005. Erosion was significantly higher below road crossings than above. Sites downstream of road crossings had significantly lower pH and significantly higher turbidity than sites upstream of road crossings. Despite differences in water quality and habitat, there was no apparent difference in aquatic-insect …


Farm Water For The North-Eastern And Eastern Wheatbelt Of Western Australia (Zones 2 And 5), Susan Murphy-White Jan 2007

Farm Water For The North-Eastern And Eastern Wheatbelt Of Western Australia (Zones 2 And 5), Susan Murphy-White

Resource management technical reports

Large proportions of Western Australia's dryland farms suffer from water supply problems in the form of shortages, poor quality or combinations of these two factors ... A regional study for the North-eastern and Eastern Wheatbelt of Western Australia was undertaken. The base data used to develop water supply areas included soil type, landscape units, geology, hydrogeology, native vegetation and existing far water resource infrastructure.


Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson Jan 2007

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …


Good Things Come In Small Packages: Tiny Plankton Producing Oxygen Near Dead Zone, Abbie Basile Jan 2007

Good Things Come In Small Packages: Tiny Plankton Producing Oxygen Near Dead Zone, Abbie Basile

Libraries Faculty & Staff Publications

(First paragraph) For many, the words “Lake Erie” bring to mind large things: big sport fish, sprawling waterfront homes, and an enormous body of water bordering four states and two countries. Similarly, much of the Lake Erie research of which the public is aware deals with larger biological organisms—larger algae and zooplankton, the small fish that eat the zooplankton, and the large fish that feed on those smaller fish. Over the years, the smaller lake life have been somewhat overlooked.


Evaluation Of Habitat Enhancement Structure Use By Spotted Bass, Stanley L. Proboszcz, Christopher S. Guy Dec 2006

Evaluation Of Habitat Enhancement Structure Use By Spotted Bass, Stanley L. Proboszcz, Christopher S. Guy

The Prairie Naturalist

Habitat enhancement is a common and effective method used to positively influence fish populations. However, there is a paucity of speciesspecific evaluations of stream habitat enhancement structures for warmwater fishes. We evaluated use of half-log, rootwad enhancement structure, and simulated undercut bank (LUNKERS) by adult and juvenile spotted bass (Micropterus punctulatus) in natural and experimental streams. Enhancement structures were installed in Otter Creek, Kansas. Adult spotted bass use of natural and enhancement structure was documented weekly during summer and fall of 2001 and 2002 with radiotelemetry. Mean total length (TL) of adult fish was 292 mm (SE = …


Perchlorate And Nitrate Remediation Efficiency And Microbial Diversity In A Containerized Wetland Bioreactor, Paula Krauter, Bill Daily Jr., Valerie Dibley, Holly Pinkart, Tina Legler Aug 2006

Perchlorate And Nitrate Remediation Efficiency And Microbial Diversity In A Containerized Wetland Bioreactor, Paula Krauter, Bill Daily Jr., Valerie Dibley, Holly Pinkart, Tina Legler

All Faculty Scholarship for the College of the Sciences

We have developed a method to remove perchlorate (14–27 μg/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than 2 yr with a stable ecosystem of indigenous organisms. This study assesses the bioreactor for long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for oxidation-reduction conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chain-reaction products …


Marine And Freshwater Cyanophages In A Laurentian Great Lake: Evidence From Infectivity Assays And Molecular Analyses Of G20 Genes, Steven W. Wilhelm, Matthew J. Carberry, Melanie L. Eldridge, Leo Poorvin, Matthew A. Saxton, Martina A. Doblin Jul 2006

Marine And Freshwater Cyanophages In A Laurentian Great Lake: Evidence From Infectivity Assays And Molecular Analyses Of G20 Genes, Steven W. Wilhelm, Matthew J. Carberry, Melanie L. Eldridge, Leo Poorvin, Matthew A. Saxton, Martina A. Doblin

OES Faculty Publications

While it is well established that viruses play an important role in the structure of marine microbial food webs, few studies have directly addressed their role in large lake systems. As part of an ongoing study of the microbial ecology of Lake Erie, we have examined the distribution and diversity of viruses in this system. One surprising result has been the pervasive distribution of cyanophages that infect the marine cyanobacterial isolate Synechococcus sp. strain WH7803. Viruses that lytically infect this cyanobacterium were identified throughout the western basin of Lake Erie, as well as in locations within the central and eastern …


Lockhart Catchment Appraisal 2005, Susan Murphy-White, P Leoni Jun 2006

Lockhart Catchment Appraisal 2005, Susan Murphy-White, P Leoni

Resource management technical reports

The Lockhart Catchment is the largest subcatchment of the Avon River Basin covering just over 3.56 million hectares, including 15 Shires running from Quairading and Bruce Rock in the north to Pingrup and Lake King in the south. This document aims to give the reader a starting point from which to further assess larger scale areas of the catchment for the purpose of planning to reverse and improve land degradation and sustainable farming in Western Australia.


Facilitating The Development Of The Strawberry Industry In Western Australia, Dennis Phillips, Aileen Reid Jan 2006

Facilitating The Development Of The Strawberry Industry In Western Australia, Dennis Phillips, Aileen Reid

Horticulture research reports

Horticulture Australia Project No. BS05001 Annual report 2005/06

This is the first of three annual reports for the Horticulture Australia project BS05001 — ‘Facilitating the development of the strawberry industry in Western Australia’. This project is managed by the Strawberry Growers Association of WA Inc. and the work is being done in collaboration with the Department of Agriculture and Food WA (DAFWA). The project has been funded by voluntary contributions from the W.A. Strawberry Producers Committee, Toolangi Strawberry Runner Growers Co-operative and DAFWA with matching funding from Horticulture Australia Ltd (HAL). The project has been funded for three years, 2005, …


Evaluation Of The Sustainable Grazing On Saline Lands - Wa Producer Network : Influence On Practice Change And Decision-Making Capacity, Rebecca Heath, Jamie Bowyer, T M. Lacey Jan 2006

Evaluation Of The Sustainable Grazing On Saline Lands - Wa Producer Network : Influence On Practice Change And Decision-Making Capacity, Rebecca Heath, Jamie Bowyer, T M. Lacey

Resource management technical reports

No abstract provided.


Natural Resource Management Issues In The Avon River Basin, Paul Galloway Jan 2006

Natural Resource Management Issues In The Avon River Basin, Paul Galloway

Resource management technical reports

Analyses the risk of soil, land and water degradation within the Avon River Basin of Western Australia. Information is based on the interpretation of the characteristics of soils and landscapes within the Avon River basin. This report deals with 15 natural resource management issues and describes the extent of each issue, the impacts that each issue will have, management options that can be used to deal with each issue, and the effectiveness of each management option in dealing with the issues.


Spatial Analyses Of Trophic Linkages Between Basins In The Great Salt Lake, Wayne A. Wurtsbaugh, David Naftz, Shane Bradt Jan 2006

Spatial Analyses Of Trophic Linkages Between Basins In The Great Salt Lake, Wayne A. Wurtsbaugh, David Naftz, Shane Bradt

Watershed Sciences Faculty Publications

Although the Great Salt Lake is frequently treated as if it were a single body of water, the natural bays and transportation causeways have divided it into a system of four bays. The bays, however, do not function independently because water, nutrients and other contaminants flow between them. The purpose of our study was to analyze the water quality in three of the bays (Farmington, Bear River and Gilbert), to determine fluxes of nutrients between them, and to determine how this was influencing brine shrimp populations in the lake. Discharge and nutrient concentrations were measured at constrictions separating the three …


Aquatic Macroinvertebrates Of The Strawberry River System In North-Central Arkansas, George L. Harp, Henry W. Robison Jan 2006

Aquatic Macroinvertebrates Of The Strawberry River System In North-Central Arkansas, George L. Harp, Henry W. Robison

Journal of the Arkansas Academy of Science

The Strav/berry River has been designated an Extraordinary Resource Water, an Ecologically Sensitive Water Body, and a Natural and Scenic Waterway. As such, it is particularly important that the biodiversity of this river system be documented thoroughly. The purpose of this research was to develop a comprehensive list of the aquatic macroinvertebrates of the Strawberry River and its major tributaries. The information was developed from a thorough literature review and by examining specimens housed in various collections of the Arkansas State University Museum of Zoology and collections of the authors. The latter included 9 collections at 4 sites along the …


Ichthyofaunal Assemblages In Three Approximate But Ecologically Diverse Streams In Clark County, Arkansas, C. Renn Tumlison, Scott Jordan, Lesley Self, Henry W. Robison Jan 2006

Ichthyofaunal Assemblages In Three Approximate But Ecologically Diverse Streams In Clark County, Arkansas, C. Renn Tumlison, Scott Jordan, Lesley Self, Henry W. Robison

Journal of the Arkansas Academy of Science

Three tributaries to the Ouachita River in eastern Clark County, Arkansas, empty into the river within a collective distance of about 9 km. The streams drain basins derived from the Wilcox formation, partially overlain by terrace and alluvial deposits. Despite their proximity, the streams are very different: L'Eau Frais has a gravel substrate and was recognized by the French as a cool water stream, Tupelo Creek is a bottomland stream from which numerous Water Tupelo (Nyssa aquatica) emerge, and Saline Bayou was named due to its marked salinity. We studied the assemblages of fishes in these 3 very different drainages …


Dynamics Of Carbon Allocation In A Deep-Water Population Of The Deciduous Kelp Pleurophycus Gardeneri (Laminariales), Clare M. Dominik, Richard C. Zimmerman Jan 2006

Dynamics Of Carbon Allocation In A Deep-Water Population Of The Deciduous Kelp Pleurophycus Gardeneri (Laminariales), Clare M. Dominik, Richard C. Zimmerman

OES Faculty Publications

Pleurophycus gardneri (Laminariales) is common in the low intertidal of the Northeast Pacific, but dominates many deep (30 to 40 m) rocky reefs in central California. Seasonal dynamics of productivity and resource allocation of a deep-water population of this deciduous, stipitate kelp were studied to understand how blade abscission affects the annual carbon budget. Patterns of growth, metabolism, and carbon storage and mobilization were measured monthly for 1 yr relative to in situ light and temperature, and used to model the annual carbon budget. The resulting carbon budget was used to determine if blade abscission effectively reduced respiratory demand during …


Evaluation Of Water-Retention Ability Of Eastern Arkansas Prairie And Agricultural Soil, Maria L. Barrenechea, Kristofor R. Brye Jan 2006

Evaluation Of Water-Retention Ability Of Eastern Arkansas Prairie And Agricultural Soil, Maria L. Barrenechea, Kristofor R. Brye

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

Agricultural land use affects soil physical properties, such as bulk density, water content, organic matter content, and soil structure; all of which in turn affect ecosystem productivity. The objective of this study was to evaluate the effects of: 1) time since aboveground biomass has been removed by haying (i.e., 0 vs. 23 years), and 2) land use (i.e., undisturbed tallgrass prairie vs. cultivated agriculture) on water-retention characteristics in a silt-loam soil of the Grand Prairie region of eastern Arkansas. Soil samples were collected from the 0- to 10-cm depth and were wetted with varying amounts of distillated water to create …


Ravensthorpe Area Catchment Appraisal 2006, A Massenbauer Jan 2006

Ravensthorpe Area Catchment Appraisal 2006, A Massenbauer

Resource management technical reports

The Ravensthorpe area covers 861, 000 hectares. Ninety percent of the study area covered in this report falls within the Ravensthorpe Shire, Western Australia. This document aims to give the reader a starting point from which to further assess larger scale areas of the catchment for the purpose of planning to reverse and improve land degradation and sustainable farming in Western Australia.


Effects Of Salinity Changes On The Photodegradation And Ultraviolet-Visible Absorbance Of Terrestrial Dissolved Organic Matter, E. C. Minor, J. Pothen, B. J. Dalzell, H. Abdulla, K. Mopper Jan 2006

Effects Of Salinity Changes On The Photodegradation And Ultraviolet-Visible Absorbance Of Terrestrial Dissolved Organic Matter, E. C. Minor, J. Pothen, B. J. Dalzell, H. Abdulla, K. Mopper

Chemistry & Biochemistry Faculty Publications

We performed laboratory studies to determine the effects of salinity on the photodegradation of dissolved organic matter (DOM) from the Great Dismal Swamp, Virginia, an important source of terrestrial DOM to the lower Chesapeake Bay. Samples were created by mixing Great Dismal Swamp water (ionic strength approximate to 0 mol L-1) with modified artificial seawater solutions of differing salinities while keeping the final dissolved organic carbon (DOC) concentration constant. These samples were then irradiated for 24 h in a light box providing ultraviolet (UV) light similar to that of natural sunlight. Light absorbance and DOC concentrations decreased after …