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Bringing real world applications for wireless sensor networks into the classroom: Telemetric monitoring of water quality in an artificial stream [2012]

Description: This report discusses research on aquatic sensors and telemetric monitoring of water quality in an artificial stream with the use of a wireless sensor networks (WSN) using the ZigBee protocol to remotely monitor an artificial aquatic ecosystem. This research is part of Research Experiences for Teachers (RET) in Sensor Education, a National Science Foundation (NSF) funded grant project.
Date: 2012
Creator: Bunn, Zac; Guerrero, Jose; Wolf, Lori; Fu, Shengli; Hoeinghaus, David; Driver, Luke et al.
Partner: UNT College of Engineering

Effects of Turbidity on Gilling Rates and Oxygen Consumption on Green Sunfish, Lepomis cyanellus

Description: Laboratory studies conducted at 5, 15, 25, and 35 C measured changes in gilling rates and oxygen consumption of green sunfish in response to exposure to bentonite clay suspensions. The tests indicate that gilling rates are not affected by bentonite clay suspensions below 2125 FTU at 5 C, 1012 FTU at 15 C, and 898 FTU at 25 C. At turbidity levels exceeding 1012 FTU at 15 C and 898 at 25 C, gilling rates increased 50-70%. Tests were inconclusive at 35 C. Oxygen consumption rates were found to be unaffected by turbid suspensions below 3500 FTU at all four temperatures. Evidence suggests that increased gilling rates under highly turbid conditions are a means of compensating for reduced respiratory efficiency and a strategy for maintaining a constant oxygen uptake. Evidence indicates that the cost of increased gilling rates is probably met by a reduction in activity.
Date: May 1974
Creator: Horkel, John Duane
Partner: UNT Libraries

A Prehistorical Record of Cultural Eutrophication from Crawford Lake, Canada

Description: Cultural eutrophication--the process by which human activities increase nutrient input rates to aquatic ecosystems and thereby cause undesirable changes in surface-water quality--is generally thought to have begun with the start of the industrial era. The prehistoric dimension of human impacts on aquatic ecosystems remains relatively undescribed, particularly in North America. Here we present fossil plankton data (diatoms and rotifers), organic and inorganic carbon accumulations, and carbon isotope ratios from a 1000-yr sediment core record from Crawford Lake, Ontario, Canada. The data documents increased nutrient input to Crawford Lake caused by Iroquoian horticultural activity from A.D. 1268 to 1486 and shows how this increased nutrient input elevated lake productivity, caused bottom-water anoxia, and irreversibly altered diatom community structure within just a few years. Iroquoian settlement in the region declined in the fifteenth century, yet diatom communities and lake circulation never recovered to the predisturbance state. A second phase of cultural eutrophication starting in A.D. 1867, initiated by Canadian agricultural disturbance, increased lake productivity but had comparatively less of an impact on diatom assemblages and carbon-storage pathways than the initial Iroquoian disturbance. This study deepens our understanding of the impact of cultural eutrophication on lake systems, highlights the lasting influence of initial environmental perturbation, and contributes to the debate on the ecological impacts of density and agricultural practices of native North American inhabitants.
Date: August 5, 2004
Creator: Ekdahl, E J; Teranes, J; Guilderson, T; Turton, C L; McAndrews, J H; Wittkop, C A et al.
Partner: UNT Libraries Government Documents Department

A general protocol for restoration of entire river catchments

Description: Large catchment basins may be viewed as ecosystems with interactive natural and cultural attributes. Stream regulation severs ecological connectivity between channels and flood plains by reducing the range of natural flow and temperature variation, reduces the capacity of the ecosystem to sustain native biodiversity and bioproduction and promotes proliferation of non-native biota. However, regulated rivers regain normative attributes, which promote recovery of native biota, as distance from the dam increases and in relation to the mode of regulation. Therefore, reregulation of flow and temperature to normative pattern, coupled with elimination of pollutants and constrainment of nonnative biota, can naturally restore damaged habitats from headwaters to mouth. The expectation is rapid recovery of depressed populations of native species. The protocol requires: restoration of seasonal temperature patterns; restoration of peak flows needed to reconnect and periodically reconfigure channel and floodplain habitats; stabilization of base flows to revitalize the shallow water habitats; maximization of dam passage to allow restoration of metapopulation structure; change in the management belief system to rely on natural habitat restoration as opposed to artificial propagation, installation of artificial instream structures (river engineering) and artificial food web control; and, practice of adaptive ecosystem management.
Date: May 28, 1996
Creator: Stanford, J.A.; Frissell, C.A.; Ward, J.V.; Liss, W.J.; Coutant, C.C.; Williams, R.N. et al.
Partner: UNT Libraries Government Documents Department

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

A methodology for assessing the impact of mutagens on aquatic ecosystems. Final report

Description: Assessments of impacts of hazardous agents (i.e., chemical and physical mutagens) on human health have focused on defining the effects of chronic exposure on individuals, with cancer being the main effect of concern. In contrast, impacts on ecosystems have traditionally been gauged by the assessment of near-term organism mortality, which is clearly not a useful endpoint for assessing the long-term effects of chronic exposures. Impacts on individual organisms that affect the long-term survival of populations are much more important but are also more difficult to define. Therefore, methods that provide accurate measures of sub-lethal effects that are linked to population survival are required so that accurate assessments of environmental damage can be made and remediation efforts, if required, can be initiated. Radioactive substances have entered aquatic environments as a result of research and production activities, intentional disposal, and accidental discharges. At several DOE sites, surface waters and sediments are contaminated with radioactive and mutagenic materials. The accident at the Chernobyl power station in the former Soviet Union (FSU) has resulted in the contamination of biota present in the Kiev Reservoir. This documents presents a methodology which addresses the effects of a direct-acting mutagen (radiation) on aquantic organisms by applying sensitive techniques for assessing damage to genetic material.
Date: March 1, 1995
Creator: Knezovich, J.P. & Martinelli, R.E.
Partner: UNT Libraries Government Documents Department

Molecular biology in marine science: Scientific questions, technological approaches, and practical implications

Description: This report describes molecular techniques that could be invaluable in addressing process-oriented problems in the ocean sciences that have perplexed oceanographers for decades, such as understanding the basis for biogeochemical processes, recruitment processes, upper-ocean dynamics, biological impacts of global warming, and ecological impacts of human activities. The coupling of highly sophisticated methods, such as satellite remote sensing, which permits synoptic monitoring of chemical, physical, and biological parameters over large areas, with the power of modern molecular tools for ``ground truthing`` at small scales could allow scientists to address questions about marine organisms and the ocean in which they live that could not be answered previously. Clearly, the marine sciences are on the threshold of an exciting new frontier of scientific discovery and economic opportunity.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

Assessing Sources of Stress to Aquatic Ecosystems: Using Biomarkers and Bioindicators to Characterize Exodure-Response Profiles of Anthropogenic Activities

Description: Establishing causal relationships between sources of environmental stressors and aquatic ecosystem health if difficult because of the many biotic and abiotic factors which can influence or modify responses of biological systems to stress, the orders of magnitude involved in extrapolation over both spatial and temporal scales, and compensatory mechanisms such as density-dependent responses that operate in populations. To address the problem of establishing causality between stressors and effects on aquatic systems, a diagnostic approach, based on exposure-response profiles for various anthropogenic activities, was developed to help identify sources of stress responsible for effects on aquatic systems at ecological significant levels of biological organization (individual, population, community). To generate these exposure-effects profiles, biomarkers of exposure were plotted against bioindicators of corresponding effects for several major anthropogenic activities including petrochemical , pulp and paper, domestic sewage, mining operations, land-development activities, and agricultural activities. Biomarkers of exposure to environmental stressors varied depending on the type of anthropogenic activity involved. Bioindicator effects, however, including histopathological lesions, bioenergetic status, individual growth, reproductive impairment, and community-level responses were similar among many of the major anthropogenic activities. This approach is valuable to help identify and diagnose sources of stressors in environments impacted by multiple stressors. By identifying the types and sources of environmental stressors, aquatic ecosystems can be more effectively protected and managed to maintain acceptable levels of environmental quality and ecosystem fitness.
Date: March 29, 1999
Creator: Adams, S.M.
Partner: UNT Libraries Government Documents Department

Lagoon Restoration Project: Final report

Description: This project is a multiyear effort focusing on energy flow in the Palace of Fine Arts lagoon just outside the Exploratorium in San Francisco. Phase 1 was a pilot study to determine the feasibility of improving biological energy flow through the small freshwater lagoon, using the expertise and resources of an environmental artist in collaboration with museum biologists and arts department staff. The primary outcome of Phase 1 is an experimental fountain exhibit inside the museum designed by public artist Laurie Lundquist with Exploratorium staff. This fountain, with signage, functions both as a model for natural aeration and filtration systems and as a focal point for museum visitors to learn about how biological processes cycle energy through aquatic systems. As part of the study of the lagoon`s health, volunteers continued biweekly bird consus from March through September, 1994. The goal was to find out whether the poor water quality of the lagoon is affecting the birds. Limited dredging was undertaken by the city Parks and Recreation Department. However, a more peermanent solution to the lagoon`s ecological problems would require an ambitious redesign of the lagoon.
Date: March 1, 1995
Partner: UNT Libraries Government Documents Department

Foothills Parkway Section 8B Final Environmental Report, Volume 3, Appendix D

Description: In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NPS, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this ER, there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constructing Section 8B with an interchange at SR416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER inventories the fishes and benthic macroinvertebrates inhabiting the aquatic ecosystems potentially affected by the proposed construction of Section 8B. Stream biological surveys were completed at 31 stream sites during the Fall of 1994. The sampling strategy for both invertebrates and fish was to survey the different taxa from all available habitats. For benthic invertebrates, a ...
Date: July 1999
Creator: Blasing, T. J.; Cada, G. F.; Carer, M.; Chin, S. M.; Dickerman, J. A.; Etnier, D. A. et al.
Partner: UNT Libraries Government Documents Department

Remedial investigation/feasibility study of the Clinch River/Poplar Creek operable unit. Volume 5

Description: This volume is in support of the findings of an investigation into contamination of the Clinch River and Poplar Creek near the Oak Ridge Reservation (for more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities there). It addresses the quality assurance objectives for measuring the data, presents selected historical data, contains data from several discrete water characterization studies, provides data supporting the sediment characterization, and contains data related to several biota characterization studies.
Date: March 1, 1996
Partner: UNT Libraries Government Documents Department

Lower granite GIS data description and collection guidelines

Description: The Lower Granite Geographic Information System (GIS) was developed jointly by the US Army Corps of Engineers (USCOE) Walla Walla District and the Pacific Northwest Laboratory (PNL). The goal of the project is to use GIS technology to analyze impacts of the drawdown mitigation option on the physical and biological environment of the Lower Granite Reservoir. The drawdown mitigation option is based on the hypothesis that faster juvenile salmon travel to the ocean would result in higher juvenile survival and greater smolt-to-adult return ratios; to accomplish this, reservoir elevations would be lowered to increase channel velocities. Altering the elevation of the reservoirs on the Snake River is expected to have a variety of impacts to the Physical environment including changes to water velocity, temperature, dissolved gases, and turbidity. The GIS was developed to evaluate these changes and the resulting impacts on the anadromous and resident fish of the Snake River, as well as other aquatic organisms and terrestrial wildlife residing in the adjacent riparian areas. The Lower Granite GIS was developed using commercial hardware and software and is supported by a commercial relational database. Much of the initial system development involved collecting and incorporating data describing the river channel characteristics, hydrologic properties, and aquatic ecology. Potentially meaningful data for the Lower Granite GIS were identified and an extensive data search was performed. Data were obtained from scientists who are analyzing the habitats, limnology, and hydrology of the Snake River. The next six sections of this document describe the bathymetry, fish abundance, substrate, sediment chemistry, and channel hydrology data.
Date: December 1, 1995
Creator: Gordon, J.L.; Evans, B.J. & Perry, E.M.
Partner: UNT Libraries Government Documents Department

Final technical report: Partial support for US participants in the 5th International Marine Biotechnology Conference, Townsville, Australia, Sept 29 - Oct 5, 2000

Description: Funding was provided for US participants in the 5th International Marine Biotechnology Conference held in Townsville, Australia from September 29 to October 5, 2000. DOE funds were used for travel awards for six US participants in this conference. DOE funds were successfully used to advance participation of US scientists in the important emerging field of marine biotechnology.
Date: April 9, 2001
Creator: Zohar, Yonathan; Hill, R. & Robb, F.
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

Third Annual Report: 2006 Pre-Construction Eelgrass Monitoring and Propagation for King County Outfall Mitigation

Description: King County proposes to build a new sewer outfall discharging to Puget Sound near Point Wells, Washington. Construction is scheduled for 2008. The Point Wells site was selected to minimize effects on the nearshore marine environment, but unavoidable impacts to eelgrass (Zostera marina) beds are anticipated during construction. To mitigate for these impacts and prepare for post-construction restoration, King County began implementation of a multi-year eelgrass monitoring and restoration program in 2004, with the primary goal of returning intertidal and shallow subtidal habitat and eelgrass to pre-construction conditions. Major program elements are a) pre-construction monitoring, i.e., documenting initial eelgrass conditions and degree of fluctuation over 5 years prior to construction, b) eelgrass transplanting, including harvesting, offsite propagating and stockpiling of local plantstock, and post-construction planting, and c) post-construction monitoring. The program is detailed in the Eelgrass Restoration and Biological Resources Implementation Workplan (King County 2006). This report describes calendar year 2006 pre-construction activities conducted by Pacific Northwest National Laboratory (PNNL) in support of King County. Activities included continued propagation of eelgrass shoots and monitoring of the experimental harvest plots in the marine outfall corridor area to evaluate recovery rates relative to harvest rates. Approximately 1500 additional shoots were harvested from the marine outfall corridor in August 2006 to supplement the plants in the propagation tank at the PNNL Marine Sciences Laboratory in Sequim, Washington, bringing the total number of shoots to 4732. Eelgrass densities were monitored in the five experimental harvest plots established in the marine outfall corridor. Changes in eelgrass density were evaluated in year-to-year comparisons with initial harvest rates. Net eelgrass density decreased from 2004 post-harvest to 2006 in all plots, despite density increases observed in 2005 in some plots and at some harvest rates. Eelgrass densities within individual subplots were highly variable from year to year, and ...
Date: February 1, 2007
Creator: Woodruff, Dana L.; Southard, Susan S.; Cullinan, Valerie I.; Kohn, Nancy P.; Anderson, Michael G. & Vavrinec, John
Partner: UNT Libraries Government Documents Department

[Development and testing of theories of population dynamics]. First annual report

Description: We report new analyses to test competing models of the Daphnia/algal interaction. Our model is good at predicting equilibrium algal densities, and if our new insights can account for stability in this system across a wide range of natural environments, this may contribute to understanding predator-prey dynamics in general.
Date: March 15, 1990
Creator: Murdoch, W. W.; Bence, J. R.; McCauley, E. & Nisbet, R. M.
Partner: UNT Libraries Government Documents Department

Growth, life history, and species interactions of bluegill sunfish (Lepomis macrochirus) under heavy predation

Description: The purpose of this study was, first, to compare growth and life history characteristics of an unfished population of bluegill sunfish (Lepomis macrochirus) in the presence of an abundant predator population to characteristic exhibited by bluegills in typical southeastern US reservoirs where the abundance of predators is reduced, but fishing is increased. The second objective was to determine if differences observed between populations were determined genetically or environmentally.
Date: December 31, 1992
Creator: Belk, M. C.
Partner: UNT Libraries Government Documents Department

Assessment of primary production and optical variability in shelf and slope waters near Cape Hatteras, North Carolina. Final project report

Description: In this project we determined primary production and optical variability in the shelf and slope waters off of Cape Hatteras, N.C. These processes were addressed in conjunction with other Ocean Margins Program investigators, during the Spring Transition period and during Summer. We found that there were significant differences in measured parameters between Spring and Summer, enabling us to develop seasonally specific carbon production and ecosystem models as well as seasonal and regional algorithm improvements for use in remote sensing applications.
Date: February 12, 2001
Creator: Redalje, Donald G. & Lohrenz, Stevern E.
Partner: UNT Libraries Government Documents Department