Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Environmental Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 17671 - 17700 of 22692

Full-Text Articles in Entire DC Network

Local And Systemic Controls On Fish And Fish Habitat In South Dakota Rivers And Streams: Implications For Management, Craig L. Milewski Jan 2001

Local And Systemic Controls On Fish And Fish Habitat In South Dakota Rivers And Streams: Implications For Management, Craig L. Milewski

Electronic Theses and Dissertations

Assessments of the health of rivers and streams in prairie environments would improve if the role of systemic patterns and processes among geologic-climatic settings in controlling physical habitat and fish communities were better defined. My research approach was based on a premise that assessments of the health of rivers and streams in prairie environments would benefit from studies that 1) examine the moderating effects of systemic patterns and processes by comparing physical habitat continua and fish communities among geologic-climatic settings, 2) determine the relative influence of locally interacting variables (e .g., channel shape and riparian vegetation) and systemic processes in …

Go to article

Population Characteristics And Sampling Methods Of Catfish For The James And Big Sioux Rivers, John E. Aterburn Jan 2001

Population Characteristics And Sampling Methods Of Catfish For The James And Big Sioux Rivers, John E. Aterburn

Electronic Theses and Dissertations

Concerns about the sustainability of catfish populations that produce large fish have increased because of abundant media images of large catfish and improvements in specialized fishing equipment. This study will help biologists address these concerns by providing important information about the channel catfish lctalurus punctarus and flathead catfish Pylodictis olivaris populations of the James and Big Sioux rivers and by assessing the effectiveness of various gears used to sample catfish. I compared the number of channel catfish and flathead catfish caught on trotlines by riverine habitat type, hook type, and bait type along with electrofishing and different hoop net combinations. …

Go to article

The Status And Distribution Of The Topeka Shiner Notropis Topeka In Eastern South Dakota, Carmen M. Blausey Jan 2001

The Status And Distribution Of The Topeka Shiner Notropis Topeka In Eastern South Dakota, Carmen M. Blausey

Electronic Theses and Dissertations

The Topeka shiner Notropis topeka is a small (< 75 mm) minnow that inhabits prairie streams in several north central plains states. Once widespread and abundant throughout its historic range, the Topeka shiner is now found only in isolated populations. Because of an 80% reduction in occurrence throughout their range, the U.S. Fish and Wildlife Service listed the Topeka shiner as endangered in January 1999. At the time, limited information on habitat preferences and dist1ibution existed for this species in South Dakota. The objectives of this study were to measure local habitat features and water quality conditions at the reach scale at Topeka shiner study sites, create a model using these data to determine favorable habitat conditions, and identify fish species commonly associated with Topeka shiners. Fish and habitat data were collected at 61 tributary sites of the James, Vermillion, and Big Sioux rivers from June through September in 1999 and 2000. Sample sites in 1999 were based on historic Topeka shiner records in the South Dakota Natural Heritage Database. Sample sites in 2000 were based on a draft GIS model identifying potential Topeka shiner streams. Fish were collected with seines between block nets and standard procedures were used to measure physical and hydrological features of stream reaches. Cyprinids dominated the fish community for each river basin during both sample years. Insectivores and omnivores were the dominant trophic classes for each river basin for both sample years. Fish community associations for Topeka shiners were based on two stepwise logistic regression models: abundance of individual species at each site and presence or absence of individual species at each site. The abundance model indicated that Topeka shiners were most commonly associated with orangespotted sunfish Lepomis lutrenis and tadpole madtoms Noturns gyrinus. The presence/absence model showed that Topeka shiners were typically associated with red shiners Notropis lutrenis, tadpole madtoms Noturns gyrinus, black bullheads Ameiurus melas, and bigmouth shiners Notropis dorsalis. Habitat preferences were based on three stepwise logistic regression models: physical habitat water quality, and substrate composition at the reach scale. The physical habitat model indicated that Topeka shiners are associated with stream reaches that had low animal use, overhanging vegetation, stream bank vegetation comprised of sedges/rushes, low depositional zones, and run macrohabitat. The water quality model did not indicate any favorable or preferred conditions. The substrate model indicated that Topeka shiners are associated with stream reaches that had fine gravel or cobble substrates. The results of my study will lead to a better understanding of Topeka shiner distribution and habitat, and aid federal and state agencies in making management decisions that provide for protection and preservation of this species.

Go to article

Impact Of Gravel Dredging Operations On Surface Water Quality In Streams In The Upper Cumberland Basin, Jeffrey D. Jack, Arthur C. Parola, Anna L. Curini, Randall Kelley, Mark N. French, D. J. Hagerty, William M. Sampson Jan 2001

Impact Of Gravel Dredging Operations On Surface Water Quality In Streams In The Upper Cumberland Basin, Jeffrey D. Jack, Arthur C. Parola, Anna L. Curini, Randall Kelley, Mark N. French, D. J. Hagerty, William M. Sampson

KWRRI Research Reports

This is a report to the USEPA, Kentucky Division of Water and the Kentucky Water Resources Research Institute, focused on the biologic and morphological impacts of gravel mining in the upper Cumberland basin.

Go to article

Growth Rate Variability And Lipofuscin Accumulation Rates In The Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey Jan 2001

Growth Rate Variability And Lipofuscin Accumulation Rates In The Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications

To better understand growth and age-pigment (lipofuscin) accumulation rates of the blue crab Callinectes sapidus under natural conditions, juveniles (33 to 94 mm carapace width) were reared in outdoor ponds for over 1 yr. Growth rates, measured by carapace width, during summer and fall exceeded all those reported in the literature; the initial carapace width of 59 ± 14 mm (mean ± SD) increased to 164 ± 15 mm within a 3 mo period. No growth occurred during winter months (November to April) at low water temperatures. Growth rates of crabs in ponds were substantially higher (von Bertalanffy growth parameter …

Go to article

Hydrogeological Characterization Of The South Oyster Bacterial Transport Site Using Geophysical Data, Susan S. Hubbard, Jinsong Chen, John Peterson, Ernest L. Majer, Kenneth H. Williams, Donald J. Swift, Brian Mailloux, Yoram Rubin Jan 2001

Hydrogeological Characterization Of The South Oyster Bacterial Transport Site Using Geophysical Data, Susan S. Hubbard, Jinsong Chen, John Peterson, Ernest L. Majer, Kenneth H. Williams, Donald J. Swift, Brian Mailloux, Yoram Rubin

OES Faculty Publications

A multidisciplinary research team has conducted a field-scale bacterial transport study within an uncontaminated sandy Pleistocene aquifer near Oyster, Virginia. The overall goal of the project was to evaluate the importance of heterogeneities in controlling the field-scale transport of bacteria that are injected into the ground for remediation purposes. Geochemical, hydrological, geological, and geophysical data were collected to characterize the site prior to conducting chemical and bacterial injection experiments. In this paper we focus on results of a hydrogeological characterization effort using geophysical data collected across a range of spatial scales. The geophysical data employed include surface ground-penetrating radar, radar …

Go to article

Utility Of Walleyes And Saugeyes As Secondary Predators In Small South Dakota Impoundments, Mark J. Ermer Jan 2001

Utility Of Walleyes And Saugeyes As Secondary Predators In Small South Dakota Impoundments, Mark J. Ermer

Electronic Theses and Dissertations

Walleye Stizostedion vitreum and saugeye (walleye x sauger S. canadense) fingerlings were concurrently stocked at equal densities into five small impoundments in 1997, 1988, and 1999 to evaluate relative survival, growth and their ability to restructure existing panfish communities. Prior to stocking, fish were differentially marked on the right or left side with freeze brands or with 700 ppm oxytetracycline hydrochloride (OTC) to allow accurate identification of each fish as a walleye (fry mark) or a saugeye (fingerling mark). Spring and fall night electrofishing was used to sample the stocked percids, as well as potential competing species such as largemouth …

Go to article

Development Of A Low-Cost, Self-Calibrating Stream Gaging Station, Gilberto Urroz, Robert C. Leines, Garryn L. Perret, Jared M. Holland, Brian E. Hunsaker Jan 2001

Development Of A Low-Cost, Self-Calibrating Stream Gaging Station, Gilberto Urroz, Robert C. Leines, Garryn L. Perret, Jared M. Holland, Brian E. Hunsaker

Reports

Executive Summary: The present report presents a review of the state-of-the-art technologies for the development of a low-cost, self-calibrating stream gaging station. The research was conducted by the Utah Water Research Laboratory with funding provided by the Utah Division of Water Resources through Project RP 110080, March 1998. The report presents a review of the current practices in stream gaging and how technologies such as remote data telemetry through the use of satellite, cellular phone communications, and radio telemetry can be used for the real-time transmission of data. The study also includes the use of Global Positioning System (GPS) for …

Go to article

Biodiversity: Connecting With The Tapestry Of Life, Elise F. Granek, Francisco Dallmeier, Alfonso Alonso, Peter H. Raven Jan 2001

Biodiversity: Connecting With The Tapestry Of Life, Elise F. Granek, Francisco Dallmeier, Alfonso Alonso, Peter H. Raven

Environmental Science and Management Faculty Publications and Presentations

Biodiversity is the extraordinary variety of life on Earth – from genes and species to ecosystems and the valuable functions they perform. E.O. Wilson, the noted biologist and author who coined the term “biodiversity,” explains it as “the very stuff of life.” Species and the ecosystems in which they live are indelibly linked. Conversion or loss of ecosystems inevitably impairs the species that depend on them. As well, changes in the life cycle of one species could impact the life cycles of many other species (including humans), alter ecosystems and ecosystem functions, and contribute to local, regional and, ultimately, global …

Go to article

Scwds Briefs: Volume 16, Number 4 (January 2001) Jan 2001

Scwds Briefs: Volume 16, Number 4 (January 2001)

Southeastern Cooperative Wildlife Disease Study: Publications


• Avian vacuolar myelinopathy (AVM) was confirmed in eight bald eagles and is suspected in another six eagles that died from mid-November 2000 through late January 2001 at Clarks Hill Lake in eastern Georgia.
• Bovine tuberculosis TB in Manitoba Elk
• CWD in a Nebraska Deer: Chronic wasting disease (CWD) of cervids has been found for the first time in a free-ranging cervid outside Colorado and Wyoming.
• Tropical Bont Tick on St. Croix: The U.S. Department of Agriculture recently announced that the tropical bont tick (Amblyomma variegatum) had been found on St. Croix in the U.S. …

Go to article

The Likely Cause Of Extinction Of The Tree Snail Orthalicus Reses Reses (Say), E.A. Forys, A. Quistorff, Craig R. Allen, D.P. Wojcik Jan 2001

The Likely Cause Of Extinction Of The Tree Snail Orthalicus Reses Reses (Say), E.A. Forys, A. Quistorff, Craig R. Allen, D.P. Wojcik

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Stock Island tree snail, Orthalicus reses reses, went extinct in its native range in the Florida Keys in 1992. Fortunately, O. r. reses has been introduced elsewhere and further reintroductions are currently planned. Before these reintroductions are implemented, it is important to try and determine which factors were most likely to have caused the decline and extinction. While habitat destruction was probably the ultimate reason why there were so few tree snails, it is likely that an interaction of habitat fragmentation and the invasion of an exotic predator caused the final decline that lead to the extinction in …

Go to article

The Non-Indigenous Ant, Solenopsis Invicta, Reduces Loggerhead Shrike And Native Insect Abundance, Craig R. Allen, R. Scott Lutz, Tim Lockley, Sherman A. Phillips Jr., Stephen Demarais Jan 2001

The Non-Indigenous Ant, Solenopsis Invicta, Reduces Loggerhead Shrike And Native Insect Abundance, Craig R. Allen, R. Scott Lutz, Tim Lockley, Sherman A. Phillips Jr., Stephen Demarais

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The red imported fire ant (Solenopsis invicta Buren) is an aggressive, non-indigenous species that is a threat to native biota in the southeastern United States. We determined the effect of S. invicta on loggerhead shrike (Lanius ludovicianus L.) abundance and investigated a possible mechanism of impact, which is a reduction in insect prey availability. We used a fire ant bait (hydramethylnon) to reduce fire ant populations on one randomly chosen member of each of five pairs of 202-ha study areas in the Texas coastal Bend region, and also measured shrike relative abundance and a volumetric index of insect …

Go to article

Red Imported Fire Ants: Impact On Biodiversity, Daniel P. Wojcik, Craig R. Allen, Richard J. Brenner, Elizabeth A. Forys, Donald P. Jouvenaz, R. Scott Lutz Jan 2001

Red Imported Fire Ants: Impact On Biodiversity, Daniel P. Wojcik, Craig R. Allen, Richard J. Brenner, Elizabeth A. Forys, Donald P. Jouvenaz, R. Scott Lutz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The red imported fire ant, Solenopsis invicta Buren (hereafter referred to as imported fire ant), long considered a regional problem, is receiving renewed attention nationwide, with infestations found in Arizona, Maryland, Nevada, New Mexico, and Virginia (Mitchell 1996). Recently, infestations discovered in several regions of California caused great public concern (Brennan 1999, Schrader 1999). Initially, infestations appeared to be isolated in almond groves in Kern County; presumably these infestations originated from bee hives transported interstate for the purpose of pollinating crops. Separately, ornamental plants arriving in Las Vegas, NV, were infested with fire ants, and records showed that the point …

Go to article

Inventory Of Parks Division Lands For Threatened And Endangered Species Habitats And Exemplary Natural Communities, Steven B. Rolfsmeier Jan 2001

Inventory Of Parks Division Lands For Threatened And Endangered Species Habitats And Exemplary Natural Communities, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Nebraska Natural Heritage Program is responsible for environmental review of state projects, including those on Parks division properties, to determine if they may impact state-listed threatened and endangered species. In addition, the Program maintains a statewide database on natural communities and rare and imperiled species. This information is used to inform conservation decision-making, including land management decisions, with a goal of conserving Nebraska’s flora and fauna, our natural legacy. The two main objectives of this inventory project were first to improve the Nebraska Game and Parks Commission’s knowledge of threatened and endangered species and their potential habitat on Parks …

Go to article

Remote Sensing Of Biotic Effects: Zebra Mussels (Dreissena Polymorpha) Influence On Water Clarity In Saginaw Bay, Lake Huron, Judith W. Budd, Thomas D. Drummer, Thomas F. Nalepa, Gary L. Fahnenstiel Jan 2001

Remote Sensing Of Biotic Effects: Zebra Mussels (Dreissena Polymorpha) Influence On Water Clarity In Saginaw Bay, Lake Huron, Judith W. Budd, Thomas D. Drummer, Thomas F. Nalepa, Gary L. Fahnenstiel

United States Department of Commerce: Staff Publications

In this study, Advanced Very High Resolution Radiometer (AVHRR) remote sensing reflectance (Rrs), imagery from 1987–1993 is used to study changes in water clarity before and after zebra mussels (Dreissena polymorpha) were discovered in Saginaw Bay, Lake Huron. Spatial and temporal trends in the data indicate distinct and persistent increases in water clarity in the inner bay after the first large recruitment of zebra mussels in the fall of 1991. The pre-Dreissena imagery show that turbidity in the inner bay was influenced by the Saginaw River discharge in spring, biological production (plankton) in summer, and …

Go to article

Changes In Diet And Body Condition Of Lake Whitefish In Southern Lake Michigan Associated With Changes In Benthos, Steven A. Pothoven, Thomas F. Nalepa, Philip J. Schneeberger, Stephen B. Brandt Jan 2001

Changes In Diet And Body Condition Of Lake Whitefish In Southern Lake Michigan Associated With Changes In Benthos, Steven A. Pothoven, Thomas F. Nalepa, Philip J. Schneeberger, Stephen B. Brandt

United States Department of Commerce: Staff Publications

We evaluated the long-term trends of the benthic macroinvertebrate community (1980–1999) and biological attributes of lake whitefish Coregonus clupeaformis (1985–1999) in southeastern Lake Michigan. We also determined what food types were important to lake whitefish in an area where the amphipod Diporeia had not yet declined in 1998 and how the diet of lake whitefish changed as Diporeia declined during 1999–2000. Zebra mussels Dreissena polymorpha invaded the study area in 1992; Diporeia began to decline in 1993 and was nearly absent by 1999. The body condition of lake whitefish decreased after 1993 and remained low thereafter. The length at age …

Go to article

Cetacean Sightings Around The Republic Of The Maldives, April 1998, Lisa T. Ballance, R. Charles Anderson, Robert L. Pitman, Kathleen Stafford, Abdullah Shaan, Zaha Waheed, Robert L. Brownell Jr. Jan 2001

Cetacean Sightings Around The Republic Of The Maldives, April 1998, Lisa T. Ballance, R. Charles Anderson, Robert L. Pitman, Kathleen Stafford, Abdullah Shaan, Zaha Waheed, Robert L. Brownell Jr.

United States Department of Commerce: Staff Publications

In April 1998, as part of a project to collect biopsy samples of putative pygmy blue whales (Balaenoptera musculus brevicauda) in the waters around the Republic of the Maldives, Indian Ocean, incidental sightings of cetaceans encountered were recorded. Using modified line-transect methods and handheld binoculars, a total of 267 sightings of 16 species of whales and dolphins were recorded during 20 at-sea days in the northeastern part of the atoll. Significant results include the following: (1) cetaceans were abundant and species diversity was high, including nearly every pantropical species of pelagic cetacean; (2) the spinner dolphin (Stenella …

Go to article

Recent Declines In Benthic Macroinvertebrate Densities In Lake Ontario, Stephen J. Lozano, Jill V. Scharold, Thomas F. Nalepa Jan 2001

Recent Declines In Benthic Macroinvertebrate Densities In Lake Ontario, Stephen J. Lozano, Jill V. Scharold, Thomas F. Nalepa

United States Department of Commerce: Staff Publications

Surveys of benthic macroinvertebrates conducted in Lake Ontario during 1994 and 1997 revealed recent declines in populations of three major taxonomic groups: Oligochaeta, Sphaeriidae, and Diporeia spp. (Amphipoda), with the most drastic reductions occurring in the latter. Results from sediment measurements were used to classify deepwater sediments into three habitat zones. Densities of all three taxa declined in the shallowest (12–88 m) of the sediment zones between 1994 and 1997; the greatest changes in density were observed for Diporeia, which declined from 3011 to 145 individuals·m–2, and for total benthic macroinvertebrates, which declined from 5831 to 1376 …

Go to article

Inhibition Of Erythrocyte Δ- Aminolevulinic Acid Dehydratase (Alad) Activity In Fish From Waters Affects By Lead Smelters, Christopher J. Schmitt, Colleen A. Caldwell, Bill Olsen, Dave Serdar Jan 2001

Inhibition Of Erythrocyte Δ- Aminolevulinic Acid Dehydratase (Alad) Activity In Fish From Waters Affects By Lead Smelters, Christopher J. Schmitt, Colleen A. Caldwell, Bill Olsen, Dave Serdar

United States Geological Survey: Staff Publications

We assessed the effects on fish of lead (Pb) released to streams by smelters located in Trail, BC (Canada), E. Helena, MT, Herculaneum, MO, and Glover, MO. Fish were collected by electrofishing from sites located downstream of smelters and from reference sites. Blood from each fish was analyzed for δ-aminolevulinic acid dehydratase (ALAD) activity and hemoglobin (Hb), and samples of blood, liver, or carcass were analyzed for Pb, zinc (Zn), or both. Fish collected downstream of all four smelters sites had elevated Pb concentrations, decreased ALAD activity, or both relative to their respective reference sites. At E. Helena, fish from …

Go to article

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induces Apoptotic Cell Death And Cytochrome P4501a Expression In Developing Fundulus Heteroclitus Embryos, Barbara Holland Toomey, Susan Bello, Mark E. Hahn, Susannah Cantrell, Peggy Wright, Donald E. Tillitt, Richard T. Di Giulio Jan 2001

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induces Apoptotic Cell Death And Cytochrome P4501a Expression In Developing Fundulus Heteroclitus Embryos, Barbara Holland Toomey, Susan Bello, Mark E. Hahn, Susannah Cantrell, Peggy Wright, Donald E. Tillitt, Richard T. Di Giulio

United States Geological Survey: Staff Publications

Fundulus heteroclitus embryos were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early development using nanoinjection or water bath exposure. TCDD caused developmental abnormalities that included hemorrhaging, loss of vascular integrity, edema, stunted development and death. The LC50 and LD50 of TCDD for Fundulus embryos were ~19.7 ± 9.5 pg TCDD/µl (water bath) and 0.25 ± 0.09 ng TCDD/g embryo (nanoinjection). To identify a possible cause for these developmental abnormalities we analyzed the effects of TCDD on apoptotic cell death and cytochrome P4501A (CYP1A) expression in the embryos. TCDD exposure increased apoptotic cell death in several tissues including brain, …

Go to article

The Spatial Variability Of Energy And Carbon Dioxide Fluxes At The Floor Of A Deciduous Forest, Kell B. Wilson, Tilden Meyers Jan 2001

The Spatial Variability Of Energy And Carbon Dioxide Fluxes At The Floor Of A Deciduous Forest, Kell B. Wilson, Tilden Meyers

United States Bureau of Land Management: Staff Publications

Fluxes of carbon dioxide, water and sensible heat were measured using three different eddy covariance systems above the forest floor of a closed deciduous forest (leaf area index ~ 6). The primary objective was to examine the representativeness of a single eddy covariance system in estimating soil respiration for time scales ranging from one-half hour to more than one week. Experiments were conducted in which the eddy covariance sensors were in one of three configurations: i) collocated, ii) separated horizontally or iii) separated vertically. A measure of the variation between the three systems (CV' 0, related to the coefficient of …

Go to article

Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend Jan 2001

Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend

Peer Reviewed Publications

The Pigeon River drains a 16,765-ha agricultural watershed in western Ottawa County, Michigan and discharges into south-central Lake Michigan. Extensive areas of wetlands in the upper watershed were drained in the 1920s, causing significantly altered hydrology characteristics by flashy discharges during storms and periods of snowmelt. We studied stream chemistry and hydrology for a four-year period between September, 1996, and October, 2000, to determine water quality status, to estimate annual nutrient exports, and to evaluate the effects of different seasonal flow types. Results of our study confirmed that the upper reaches of the Pigeon River experience chronically degraded water quality, …

Go to article

Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Karen Steidinger, Jan Landsberg, R. William Richardson, Earnest Truby, Barbara Blakesley, Paula Scott, Patricia Tester, Torstein Tengs, Patrice Mason, Stever Morton, David Seaborn, Wayne Litaker, Kimberly Reece, David Oldach, Leonard Haas, Gerardo Vasta Jan 2001

Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Karen Steidinger, Jan Landsberg, R. William Richardson, Earnest Truby, Barbara Blakesley, Paula Scott, Patricia Tester, Torstein Tengs, Patrice Mason, Stever Morton, David Seaborn, Wayne Litaker, Kimberly Reece, David Oldach, Leonard Haas, Gerardo Vasta

Biological Sciences Faculty Publications

Dinoflagellates can be classified both botanically and zoologically; however, they are typically put in the botanical division Pyrrhophyta. As a group they appear most related to the protistan ciliates and apicomplexans at the ultrastructure level. Within the Pyrrhophyta are both unarmored and armored forms of the dominant, motile flagellated stage. Unarmored dinoflagellates do not have thecal or wall plates arranged in specific series, whereas armored species have plates that vary in thickness but are specific in number and arrangement. In armored dinoflagellates, the plate pattern and tabulation is a diagnostic character at the family, subfamily, and even genus levels. In …

Go to article

Spatial Assessment Of Nonpoint Phosphorus Sources Using Streambed Sediment Monitoring In The Kings River Basin, Nw Arkansas, Jason W. White Jan 2001

Spatial Assessment Of Nonpoint Phosphorus Sources Using Streambed Sediment Monitoring In The Kings River Basin, Nw Arkansas, Jason W. White

Graduate Theses/Dissertations

This study of the Kings River Basin provides a watershed-scale assessment of streambed sediment-Phosphorus (P) and its sources on the landscape. The Kings River drains into Table Rock Lake where surface algal blooms have concerned water scientists and disrupted summer tourism. There are questions about how sediment loads, widespread poultry and cattle operations, and sewage treatment plants are affecting water quality. Previous water quality studies across the U.S. have generally evaluated watercolurnn P. In contrast, few studies have used streambed sediment monitoring to detect P levels at a watershed-scale, and none have been attempted in the Kings River Basin. Sediment …

Go to article

Species And Ecosystem Conservation: An Interdisciplinary Approach, Tim W. Clark, Michael J. Stevenson, Kim Ziegelmayer Jan 2001

Species And Ecosystem Conservation: An Interdisciplinary Approach, Tim W. Clark, Michael J. Stevenson, Kim Ziegelmayer

Yale School of the Environment Bulletin Series

No abstract provided.

Go to article

The Atlantic Sea Scallop Fishery In The U.S.And Canada: A Natural Experiment In Fisheries Management Regimes, Robert Repetto Jan 2001

The Atlantic Sea Scallop Fishery In The U.S.And Canada: A Natural Experiment In Fisheries Management Regimes, Robert Repetto

Yale School of the Environment Publications Series

The Atlantic sea scallop fisheries in the U.S. and Canadian offshore waters provide a natural experiment in fisheries management regimes. Starting in 1986, in side by side areas of George’s Bank, Canada adopted a rights-based approach while the U.S. continued with effort controls. Analysis of their experiences shows that the resource has been better maintained in Canada with lower fishing effort, that the Canadian fishing industry has become more prosperous and innovative relative to that in the U.S., and that the Canadian co-management regime is more cooperative. These results suggest that systematic evaluation of actual experience with rights-based fishery management …

Go to article

Municipal Waste Characteristics And Management In Pantai Dalam, Kuala Lumpur, Ratanam Andythaven Jan 2001

Municipal Waste Characteristics And Management In Pantai Dalam, Kuala Lumpur, Ratanam Andythaven

Student Works (2000-2009)

The primary purpose of this research was to study comprehensively the municipal waste generation (rate, quantity), waste characterization including (physical, chemical and biological parameters), heavy metal content, waste recovery and recycling, and socio economic aspects of municipal solid waste (MSW) generation and management in Taman Bukit Angkasa, Pantai Dalam, Kuala Lumpur and the surrounding areas. The waste characterization and management was determined with actual field observations coupled with questionnaire survey from a random sample of 250 households (200 flats houses, 25 long houses and 25 squatter residences). The quantification and other parameters (heavy metals, water extractable nutrients, nitrogen, pH, acidity, …

Go to article

Municipal Wastewater Treatment Using Sequencing Batch Reactor (Sbr) Under Tropical Conditions, Maria Violetta Thomas Jan 2001

Municipal Wastewater Treatment Using Sequencing Batch Reactor (Sbr) Under Tropical Conditions, Maria Violetta Thomas

Student Works (2000-2009)

In this research project a Sequencing Batch Reactor (SBR) plant was tested for performance in terms of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Suspended Solids (SS), under different temporal conditions. In addition, the removal of biological nutrients, namely ammoniacal nitrogen, nitrate nitrogen and phosphorous in the form of phosphate, from the sewage, with anaerobic and aerobic operations using SBR was studied. The performance of the SBR plant was observed under two operating conditions whereby the variable studied was the total cycle time of the SBR process; i.e. 8-hour cycle mode and 6-hour cycle mode. The effluent quality …

Go to article

Evaluation Of In Situ Bioremediation Approaches In Meeting International Standards For Organic And Residual Metals Toxicity In Soils, Jason Allan Mcdonald Jan 2001

Evaluation Of In Situ Bioremediation Approaches In Meeting International Standards For Organic And Residual Metals Toxicity In Soils, Jason Allan Mcdonald

LSU Master's Theses

Drilling fluids and muds are an essential component of the rotary drilling process used to drill for oil and gas on land and in offshore environments. However, the bioaccumulation of petroleum contaminated soils/drilling mud due to oil and natural gas exploration has posed a major environmental concern due to its prolonged environmental persistence and its leachability below the rhizosphere. The main objectives of this research were: (i) To assess initial toxicity of drilling mud and related contaminated soils from an agricultural setting in Galliano, Sicily (Phase one) and (ii) To develop a low intervention bioremediation approach using bioplug technology to …

Go to article

Relationships Between Stream Order And Management Priority: A Water Quality Case Study, David Weaver, Adrian Reed, John Grant Jan 2001

Relationships Between Stream Order And Management Priority: A Water Quality Case Study, David Weaver, Adrian Reed, John Grant

Conference papers and presentations

Seagrass, which once dominated the habitat of Oyster Harbour on the south coast of Western Australia has been replaced by macroalgae because of increased nutrient and sediment discharge from the rural dominated catchment. Total Phosphorus (TP), Total Nitrogen (TN), Suspended Sediment (SS) and Electrical Conductivity (EC) concentrations from a catchment – wide (168 sites), event-driven snapshot, water quality monitoring program conducted from 1994 to 1996, were analysed in relation to stream order and published survey data on riparian zone condition. This analysis was performed to examine relationships between stream order, riparian zone condition and water quality, and implications for the …

Go to article

First Prev Next Last