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Testing and Evaluation of Environmental Fate Models Using Aquatic Microcosms and Three Organic Chemicals

Description: Two compartment (sediment and water) flow-through model ecosystems were constructed to investigate the compartmentalization of different organic chemicals. Lindane, naphthalene, and mirex were pumped into the systems and resultant compartmental chemical concentrations determined. Steady state concentrations were compared to those predicted by two environmental fate models - EXAMS (Exposure Analysis Modeling System) and SLSA (Simplified Lake and Stream Analysis) which were developed by EPA-Athens, Georgia and HydroQual, Inc., respectively.
Date: December 1983
Creator: Staples, Charles A. (Charles Allen)
Partner: UNT Libraries

Extracting growth rates from the non-laminated coralline sponge Astrosclera willeyana using "bomb" radiocarbon

Description: Coralline sponges have the potential to fill in gaps in our understanding of subsurface oceanographic variability. However, one disadvantage they have compared to hermatypic reef building coral proxies is that they do not have annual density bands and need to be radiometrically dated for an age determination. To elucidate growth rate variability we have measured radiocarbon in 1 mm increments from Astrosclera willeyana sponges collected off the Central and Northern Great Barrier Reef (GBR) and from Truk in the Caroline Islands and compared these radiocarbon profiles to independently dated coral radiocarbon records. Growth rates of the GBR sponges average 1.2 {+-} 0.3 and 1.0 {+-} 0.3 mm yr{sup -1}, north and central respectively but can vary by a factor of two. The growth rate of the Truk sponge averages 1.2 {+-} 0.1 mm yr{sup -1}. These growth rates are significantly faster to those measured for other GBR Astrosclera willeyana sponges (0.2 mm yr{sup -1}) by Calcein staining (Woerheide 1988).
Date: June 30, 2004
Creator: Fallon, S & Guilderson, T
Partner: UNT Libraries Government Documents Department

Selected Technology Issues in U.S. Aquaculture

Description: This report discusses different aquatic species that are produced in the United States, including various animal and plant ornamentals, species for environmental remediation, industrial and pharmaceutical feedstocks, and products for biomedical research.
Date: September 1995
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

DIALOG: Fostering Early Career Development Across the Aquatic Sciences

Description: A total of 447 dissertation abstracts were received for the DIALOG V Program, with 146 individuals applying for the DIALOG V Symposium; 47 were invited and 45 have accepted. This represents a significant increase compared to the DIALOG IV Program in which 221 abstracts were registered and 124 applied for the symposium. The importance of the dissertation registration service is indicated by the increasing number of individuals who take time to register their dissertation even when they are not interested in applying to the symposium. The number of visits to the webpage has also increased significantly over the years. This also reflects graduate interest in being part of the on-line Dissertation Registry and receiving the weekly electronic DIALOG Newsletter. See http://aslo.org/phd.html for details. The DIALOG symposium reaches approximately 40 new PI's at a pivotal point in their research careers. Based on their comments, the symposium changes the way participants think, communicate, and approach their research. The science community and the general population will benefit from the perspectives these new PI's bring back to their home institutions and share with their students and colleagues. This group should act as a catalyst to move the entire field in exciting new, interdisciplinary directions. To reach more graduates, plans are underway to establish the symposium on an annual basis. By facilitating the development of close collegial ties, symposium participants come away with a network of colleagues from around the globe with interests in aquatic science research and education. Past participants are collaborating on research proposals, and all have noted that participation has enabled them to develop a more interdisciplinary view of their field, influencing the way they interpret, communicate, and approacli their research. The dissertation registry provides a unique introduction to the work of this most recent generation of aquatic scientists. Each year increasing ...
Date: November 14, 2004
Creator: Caroline Susan Weiler, PhD
Partner: UNT Libraries Government Documents Department

Effects of Electromagnetic Fields on Fish and Invertebrates

Description: In this progress report, we describe the preliminary experiments conducted with three fish and one invertebrate species to determine the effects of exposure to electromagnetic fields. During fiscal year 2010, experiments were conducted with coho salmon (Onchrohychus kisutch), California halibut (Paralicthys californicus), Atlantic halibut (Hippoglossus hippoglossus), and Dungeness crab (Cancer magister). The work described supports Task 2.1.3: Effects on Aquatic Organisms, Subtask 2.1.3.1: Electromagnetic Fields.
Date: October 13, 2010
Creator: Schultz, Irvin R.; Woodruff, Dana L.; Marshall, Kathryn E.; Pratt, William J. & Roesijadi, Guritno
Partner: UNT Libraries Government Documents Department

International Collaboration on CO2 Sequestration

Description: This reporting period covers the first half of the two-year sub-task, which includes a review of recent and ongoing engineering studies concerning practical modes for the ocean discharge of CO{sub 2}, review of recent and ongoing experimental studies concerning the rates (and extent) of formation and dissolution for CO{sub 2} hydrates, review of recent and ongoing biological studies concerning organism response to reduced pH and increased CO{sub 2} concentration, and the definition of discharge scenarios. These steps have been successfully completed. Results-to-date were presented at the Annual Fall Meeting of AGU (December 2005) and will be presented at the Annual DOE Meeting on Carbon Capture and Sequestration (May, 2006). The objective during this reporting period was to begin a two-year sub-task to update an assessment of environmental impacts from direct ocean sequestration. The approach is based on the work of Auerbach et al. (1997) and Caulfield et al. (1997) to assess acute impacts, but uses updated information concerning injection scenarios and bioassays.
Date: May 19, 2006
Creator: Herzog, Howard J. & Adams, E. Eric
Partner: UNT Libraries Government Documents Department

INTERNATIONAL COLLABORATION ON CO2 SEQUESTRATION

Description: After the permit to conduct a field experiment in Norway was revoked on August 22, 2002, we started executing our contingency plan to conduct a cruise at the Loihi Seamount in Hawaii in December 2002. After a few intense months of preparation, the cruise took place on December 3-13, 2002. In total, eight dives were made with the Pisces V submarine. The primary goal of the experiment was to assess the effect of CO{sub 2} on marine organisms. Studies were done using scavenger traps, as well as collecting water samples and surveying the natural CO{sub 2} plume at the Loihi Seamount. This report documents the experiment in more detail as summarized by the various participants. The data was still being analyzed at the end of this reporting period, so no results are reported here. Both papers and a video on the experiment are being prepared. Some related modeling work is presented in an Appendix in the form of a paper submitted to the Journal of Marine Environmental Engineering. The main goal of our work during this reporting period (August 23, 2002-August 23, 2003) was to conduct an experimental cruise at the Loihi Seamount in the Hawaiian Islands. The work included preparation for the cruise, conducting the survey cruise, and analyzing the results. The cruise took place from December 3-13, 2002.
Date: March 1, 2004
Creator: Herzog, Howard J. & Adams, E. Eric
Partner: UNT Libraries Government Documents Department

BPA-Solicited Technical Review of "Echo Meadows Project Winter Artificial Recharge: Final Report for 2001 Baseline", Technical Report 2004.

Description: The purpose of this report was to provide, at BPA's request, a technical review of interim products received for Project 2001-015-00 under contract 6925. BPA sometimes solicits technical reviews for Fish and Wildlife products or issues where outside expertise is required. External review of complex project deliverables assures BPA as a funding agency that the contractor is continuing with scientifically-credible experimental techniques envisioned in the original proposal. If the project's methodology proves feasible, there could be potential applications beyond the project area to similar situations in the Columbia Basin. The Experiment involves artificial flooding during high flow periods and a determination of the portion of the return flows that end up in the Umatilla River during low flow months and within acceptable water quality parameters (e.g., low temperature, few contaminants). Flooding could be a critical water source for aquatic organisms at times of the year when flows in the lower reaches of the Umatilla River are low and water is warmer than would be desired. The experiment was proposed to test whether 'this process, recharges the shallow aquifers of the old flood plain, for natural filtration through the alluvial soils as it returns to the Umatilla River, cleaner and cooler (about 50 degree Fahrenheit) five to six month later (about July and August) substantially cooling the river and [making it] more beneficial to anadromous [fish]'. A substantial amount of preliminary data had been collected and preliminary results were submitted in an interim report 'Echo Meadows Project Winter Artificial Recharge: Final Report for 2001 Baseline (December 2002)'. A substantial amount of addition funding was provided for the last cycle of flooding (Phases II) and final analyses of the full compliment of data collected over the life of the contract (Phase III). Third party scientific review may assist the contractor in producing ...
Date: February 1, 2004
Creator: Morgan, David
Partner: UNT Libraries Government Documents Department

Water Quality

Description: Lesson plan containing a collection of activities and resources regarding water quality that meet state education standards and national sustainability standards for the 6th grade level.
Date: June 26, 2014
Creator: Treadway, Heather
Partner: UNT Office of Sustainability

Effects of Suspended Solids on Bioavailability of Chemicals to Daphnia magna and Pimephales promelas

Description: Three suspended solids types containing a range of physicochemical characteristics were used to determine the effect of suspended solids on the bioavailability of acenaphthene, 1,2,4,5-tetrachlorobenzene, zinc, and chlordane to Daphnia magna and Pimephales promelas. Generally, the bioavailability of zinc and chlordane decreased due to interactions with all suspended solids types while bioavailability of acenaphthene and 1,2,4,5-tetrachlorobenzene were not clearly reduced. Partition coefficients and slope of dose-response curves related chemical characteristics and organism sensitivity, respectively, to experimentally determined results. It is believed that the biologically available form of these chemicals to Daphnia magna and Pimephales promelas resides in the aqueous phase.
Date: December 1984
Creator: Hall, W. Scott (Warren Scott)
Partner: UNT Libraries

Planning aquatic ecosystem restoration monitoring programs

Description: This study was conducted as part of the Evaluation of Environmental Investments Research Program (EEIRP). The EEIRP is sponsored by the US Army Corps of Engineers. The objectives of this work are to (1) identify relevant approaches and features for environmental investment measures to be applied throughout the project life; (2) develop methods to access the effectiveness of the approach or feature for providing the intended environmental output; (3) develop and provide guidance for formulating environmental projects; and (4) provide guidance for formulating and identifying relevant cost components of alternate restoration plans.
Date: January 1, 1997
Creator: Thom, R.M. & Wellman, K.F.
Partner: UNT Libraries Government Documents Department

Simulating living organisms with populations of point vortices

Description: The author has found that time-averaged images of small populations of point vortices can exhibit motions suggestive of the behavior of individual organisms. As an example, the author shows that collections of point vortices confined in a box and subjected to heating can generate patterns that are broadly similar to interspecies defense in certain sea anemones. It is speculated that other simple dynamical systems can be found to produce similar complex organism-like behavior.
Date: July 1, 1995
Creator: Schmieder, R.W.
Partner: UNT Libraries Government Documents Department

Cycles in fossil diversity

Description: It is well-known that the diversity of life appears to fluctuate during the course the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0-542 Ma). Using Sepkoski's compendium of the first and last stratigraphic appearances of 36380 marine genera, we report a strong 62 {+-} 3 Myr cycle, which is particularly strong in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski may be an aspect of this cycle. Because of the high statistical significance, we also consider contributing environmental factors and possible causes.
Date: October 20, 2004
Creator: Rohde, Robert A. & Muller, Richard A.
Partner: UNT Libraries Government Documents Department

Field Validation of Toxicity Tests to Evaluate the Potential for Beneficial Use of Produced Water

Description: This study investigated potential biological effects of produced water contamination derived from occasional surface overflow and possible subsurface intrusion at an oil production site along the shore of Skiatook Lake, Oklahoma. We monitored basic chemistry and acute toxicity to a suite of standard aquatic test species (fathead minnow-Pimephales promelas, Daphnia pulex, Daphnia magna, and Ceriodaphnia dubia) in produced water and in samples taken from shallow groundwater wells on the site. Toxicity identification evaluations and ion toxicity modeling were used to identify toxic constituents in the samples. Lake sediment at the oil production site and at a reference site were also analyzed for brine intrusion chemically and by testing sediment toxicity using the benthic invertebrates, Chironomus dilutus, and Hyallela azteca. Sediment quality was also assessed with in situ survival and growth studies with H. azteca and the Asian clam, Corbicula fluminea, and by benthic macroinvertebrate community sampling. The produced water was acutely toxic to the aquatic test organisms at concentrations ranging from 1% to 10% of the whole produced water sample. Toxicity identification evaluation and ion toxicity modeling indicated major ion salts and hydrocarbons were the primary mixture toxicants. The standardized test species used in the laboratory bioassays exhibited differences in sensitivity to these two general classes of contaminants, which underscores the importance of using multiple species when evaluating produced water toxicity. Toxicity of groundwater was greater in samples from wells near a produced water injection well and an evaporation pond. Principle component analyses (PCA) of chemical data derived from the groundwater wells indicated dilution by lake water and possible biogeochemical reactions as factors that ameliorated groundwater toxicity. Elevated concentrations of major ions were found in pore water from lake sediments, but toxicity from these ions was limited to sediment depths of 10 cm or greater, which is outside of the ...
Date: March 31, 2008
Creator: Bidwell, Joseph; Fisher, Jonathan & Cooper, Naomi
Partner: UNT Libraries Government Documents Department

Contrasting food web linkages for the grazing pathway in 3 temperate forested streams using {sup 15}N as a tracer

Description: Nitrogen is a critical element controlling the productivity and dynamics of stream ecosystems and many streams are limited by the supply of biologically available nitrogen. The authors are learning more about the fate of inorganic nitrogen entering streams through {sup 15}N tracer additions. The Lotic Intersite Nitrogen Experiment (LINX) is studying the uptake, cycling, and fate of {sup 15}N-NH{sub 4} in the stream food web of 10 streams draining different biomes. Using the {sup 15}N tracer method and data from 3 sites in the study, the authors can differentiate patterns in the cycling of nitrogen through the grazing pathway (N from the epilithon to grazing macroinvertebrates) for 3 temperate forested streams. Here, they quantify the relationship between the dominant grazer and its proposed food resource, the epilithon, by comparing {sup 15}N levels of grazers with those of the epilithon, as well as the biomass, nitrogen content, and chlorophyll a standing stocks of the epilithon in 3 streams.
Date: November 1, 1998
Creator: Tank, J.L.; Mulholland, P.J.; Meyer, J.L.; Bowden, W.B.; Webster, J.R. & Peterson, B.J.
Partner: UNT Libraries Government Documents Department

Clinch River - Environmental Restoration Program (CR-ERP) study, ambient water toxicity

Description: Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of April 14-21, 1994, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 4.3, Poplar Creek Mile 5.1, and Poplar Creek Mile 6.0 on April 13, 15, and 18. Samples were partitioned (split) and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to daphnids in undiluted samples; however, toxicity to fathead minnows (significantly reduced survival) was demonstrated in undiluted samples from Poplar Creek Miles 4.3 and 6.0 in testing conducted by TVA based on hypothesis testing of data. Daphnid reproduction was significantly less than controls in 50 percent dilutions of samples from Poplar Creek Miles 4.3 and 6.0, while no toxicity to fathead minnows was shown in diluted (50 percent) samples.
Date: June 1, 1997
Creator: Simbeck, D.J.
Partner: UNT Libraries Government Documents Department

Par Pond vegetation status Summer 1995 -- Summary

Description: The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995. Communities similar to the pre-drawdown, Par Pond aquatic plant communities are becoming re-established. Emergent beds of maidencane, lotus, waterlily, and watershield are extensive and well developed. Cattail occurrence continued to increase during the summer, but large beds common to Par Pond prior to the drawdown have not formed. Estimates from SPOT HRV, remote sensing satellite data indicated that as much as 120 hectares of emergent wetlands vegetation may have been present along the Par Pond shoreline by early October, 1995. To track the continued development of macrophytes in Par Pond, future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.
Date: January 1996
Creator: Mackey, H. E., Jr. & Riley, R. S.
Partner: UNT Libraries Government Documents Department

Par Pond vegetation status Summer 1995 -- June survey descriptive summary

Description: The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the shoreline aquatic plant communities in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level, indicated that much of the original plant communities and the intermediate shoreline communities present on the exposed sediments have been lost. The extensive old-field and emergent marsh communities that were present on the exposed shoreline during the drawdown have been flooded and much of the pre-drawdown Par Pond aquatic plant communities have not had sufficient time for re-establishment. The shoreline does, however, have extensive beds of maidencane which extend from the shoreline margin to areas as deep as 2 and perhaps 3 meters. Scattered individual plants of lotus and watershield are common and may indicate likely directions of future wetland development in Par Pond. In addition, within isolated coves, which apparently received ground water seepage and/or stream surface flows during the period of the Par Pond draw down, extensive beds of waterlilies and spike rush are common. Invasion of willow and red maple occurred along the lake shoreline as well. Although not absent from this survey, evidence of the extensive redevelopment of the large cattail and eel grass beds was not observed in this first survey of Par Pond. Future surveys during the growing seasons of 1995, 1996, and 1997 along with the evaluation of satellite date to map the areal extent of the macrophyte beds of Par Pond are planned.
Date: June 1, 1995
Creator: Mackey, H.E. Jr. & Riley, R.S.
Partner: UNT Libraries Government Documents Department

Par Pond vegetation status 1996

Description: The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995, and into the early spring and late summer of 1996. Communities similar to the pre-drawdown, Par Pond aquatic plant communities continue to become re-established. Emergent beds of maidencane, lotus, waterlily, watershield, and Pontederia are extensive and well developed. Measures of percent cover, width of beds, and estimates of area of coverage with satellite data indicate regrowth within two years of from 40 to 60% of levels prior to the draw down. Cattail occurrence continued to increase during the summer of 1996, especially in the former warm arm of Par Pond, but large beds common to Par Pond prior to the draw down still have not formed. Lotus has invaded and occupies many of the areas formerly dominated by cattail beds. To track the continued development of macrophytes in Par Pond, future surveys through the summer and early fall of 1997, along with the evaluation of satellite data to map the extent of the macrophyte beds of Par Pond, are planned.
Date: December 1, 1996
Creator: Mackey, H.E. Jr. & Riley, R.S.
Partner: UNT Libraries Government Documents Department

Proceedings from a Workshop on Ecological Carrying Capacity of Salmonids in the Columbia River Basin : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 3 of 4, Final Report.

Description: This report contains the proceedings of a workshop held during 1995 in Portland, Oregon. The objective of the workshop was to assemble a group of experts that could help us define carrying capacity for Columbia River Basin salmonids. The workshop was one activity designed to answer the questions asked in Measure 7.1A of the Council`s Fish and Wildlife Program. Based, in part, on the information we learned during the workshop we concluded that the approach inherent in 7.1A will not increase understanding of ecology, carrying capacity, or limiting factors that influence salmon under current conditions. Measure 7.1A requires a definition of carrying capacity and a list of determinants (limiting factors) of capacity. The implication or inference then follows that by asking what we know and do not know about the determinants will lead to research that increases our understanding of what is limiting salmon survival. It is then assumed that research results will point to management actions that can remove or repair the limiting factors. Most ecologists and fisheries scientists that have studied carrying capacity clearly conclude that this approach is an oversimplification of complex ecological processes. To pursue the capacity parameter, that is, a single number or set of numbers that quantify how many salmon the basin or any part of the basin can support, is meaningless by itself and will not provide useful information.
Date: May 1996
Creator: Johnson, Gary E.; Neitzel, D.A. & Mavros, William V.
Partner: UNT Libraries Government Documents Department

Par Pond vegetation status Summer 1995 -- September survey descriptive summary

Description: The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this mid-September survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maidencane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys during the late growing seasons of 1995, and throughout 1996 and 1997, along with the evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.
Date: September 1, 1995
Creator: Mackey, H.E. Jr. & Riley, R.S.
Partner: UNT Libraries Government Documents Department