Download or read book Influence of Methylmercury from Tributary Streams on Mercury Levels in Savannah River Asiatic Clams written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Average methylmercury levels in five Savannah River tributary streams sampled 11 times over two years were nearly twice as high as in the Savannah River. Total mercury levels in the tributaries did not differ significantly from the river. All of the tributaries drained extensive wetlands that would be expected to support comparatively high rates of methylation. Mercury concentrations in Asiatic clams (Corbicula fluminea) collected from the discharge plumes of Savannah River tributaries were significantly higher than in Asiatic clams collected from the Savannah River upstream from the tributary mouths . These results indicate that streams draining wetlands into coastal plain rivers can create localized areas of elevated methylmercury with resulting increases in the mercury levels of river biota.

Download or read book FINAL REPORT ON THE AQUATIC MERCURY ASSESSMENT STUDY written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In February 2000, the United States Environmental Protection Agency (EPA) Region 4 issued a proposed Total Maximum Daily Load (TMDL) for total mercury in the middle and lower Savannah River. The initial TMDL, which would have imposed a 1 ng/l mercury limit for discharges to the middle/lower Savannah River, was revised to 2.8 ng/l in the final TMDL released in February 2001. The TMDL was intended to protect people from the consumption of contaminated fish, which is the major route of mercury exposure to humans. The most bioaccumulative form of mercury is methylmercury, which is produced in aquatic environments by the action of microorganisms on inorganic mercury. Because of the environmental and economic significance of the mercury discharge limits that would have been imposed by the TMDL, the Savannah River Site (SRS) initiated several studies concerning: (1) mercury in SRS discharges, SRS streams and the Savannah River, (2) mercury bioaccumulation factors for Savannah River fish, (3) the use of clams to monitor the influence of mercury from tributary streams on biota in the Savannah River, and (4) mercury in rainwater falling on the SRS. The results of these studies are presented in detail in this report. The first study documented the occurrence, distribution and variation of total and methylmercury at SRS industrial outfalls, principal SRS streams and the Savannah River where it forms the border with the SRS. All of the analyses were performed using the EPA Method 1630/31 ultra low-level and contaminant-free techniques for measuring total and methylmercury. Total mercury at National Pollutant Discharge Elimination System (NPDES) outfalls ranged from 0.31-604 ng/l with a mean of 8.71 ng/l. Mercury-contaminated groundwater was the source for outfalls with significantly elevated mercury concentrations. Total mercury in SRS streams ranged from 0.95-15.7 ng/l. Mean total mercury levels in the streams varied from 2.39 ng/l in Pen Branch to 5.26 ng/l in Tims Branch. Methylmercury ranged from 0.002 ng/l in Upper Three Runs to 2.60 ng/l in Tims Branch. Total mercury in the Savannah River ranged from 0.62 ng/l to 43.9 ng/l, and methylmercury ranged from 0.036 ng/l to 7.54 ng/l. Both total and methylmercury concentrations were consistently high in the river near the mouth of Steel Creek. Total mercury was positively correlated with methylmercury (r = 0.88). Total mercury bound to particulates ranged from 41% to 57% in the river and from 28% to 90% in the streams. Particulate methylmercury varied from 9% to 37% in the river and from 6% to 79% in the streams. Small temporary pools in the Savannah River swamp area near and around Fourmile Branch had the highest concentrations observed in the Savannah River watershed, reaching 1,890 ng/l for total mercury and 34.0 ng/l for methylmercury. The second study developed a mercury bioaccumulation factor (BAF) for the Savannah River near SRS. A BAF is the ratio of the concentration of mercury in fish flesh to the concentration of mercury in the water. BAFs are important in the TMDL process because target concentrations for mercury in water are computed from BAFs. Mercury BAFs are known to differ substantially among fish species, water bodies, and possibly seasons. Knowledge of such variation is needed to determine a BAF that accurately represents average and extreme conditions in the water body under study. Analysis of fish tissue and aqueous methylmercury samples collected at a number of locations and over several seasons in a 110 km (68 mile) reach of the Savannah River demonstrated that BAFs for each species under study varied by factors of three to eight. Influences on BAF variability were location, habitat and season-related differences in fish mercury levels and seasonal differences in methylmercury levels in the water. Overall (all locations, habitats, and seasons) average BAFs were 3.7 x 106 for largemouth bass, 1.4 x 106 for sunfishes, and 2.5 x 106 for white catfish. This study showed that determination of representative BAFs for large rivers requires the collection of large numbers of fish and aqueous methylmercury samples over at least one complete seasonal cycle from the entire area and all habitats to be represented by the TMDL. The third study concerned the use of clams as an indicator of the influence of SRS discharges on mercury levels in Savannah River biota. Mercury levels were compared in Asiatic clams (Corbicula fluminea) collected from the discharge plumes and just upstream of the mouths of SRS creeks and two creeks located downstream from the SRS. Asiatic clams were selected for study because their relatively sedentary behavior made them a better indicator of local mercury exposure than mobile organisms.

Download or read book Index Medicus written by and published by . This book was released on 2004 with total page 2520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1963- include as pt. 2 of the Jan. issue: Medical subject headings.

Download or read book Mercury in Fish Bed Sediment and Water from Streams Across the United States 1998 2005 written by Barbara C. Scudder and published by DIANE Publishing. This book was released on 2010-08 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Report on how mercury (Hg) was examined in top-predator fish, bed sediment, and water from streams that spanned regional and national gradients of Hg source strength and other factors thought to influence methylmercury bioaccum. Sampled settings include stream basins that were agr¿l, urbanized, undeveloped, and mined. Predator fish were targeted for collection, and composited samples of fish were analyzed for total Hg (THg), as most of the Hg found in fish tissue is MeHg. Samples of bed sediment and stream water were analyzed for THg, MeHg, and characteristics thought to affect Hg methylation, such as loss-on-ignition and acid-volatile sulfide in bed sediment, and pH, dissolved organic carbon, and dissolved sulfate in water. Illus.

Download or read book Mercury in Fish Bed Sediment and Water from Streams Across the United States 1998 2005 written by and published by . This book was released on 2009 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Influences on Mercury Bioaccumulation Factors for the Savannah River written by and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury TMDLs (Total Maximum Daily Loads) are a regulatory instrument designed to reduce the amount of mercury entering a water body and ultimately to control the bioaccumulation of mercury in fish. TMDLs are based on a BAF (bioaccumulation factor), which is the ratio of methyl mercury in fish to dissolved methyl mercury in water. Analysis of fish tissue and aqueous methyl mercury samples collected at a number of locations and over several seasons in a 118 km reach of the Savannah River demonstrated that species specific BAFs varied by factors of three to eight. Factors contributing to BAF variability were location, habitat and season related differences in fish muscle tissue mercury levels and seasonal differences in dissolved methyl mercury levels. Overall (all locations, habitats, and seasons) average BAFs were 3.7 x 106 for largemouth bass, 1.4 x 106 for sunfishes, and 2.5 x 106 for white catfish. Inaccurate and imprecise BAFs can result in unnecessary economic impact or insufficient protection of human health. Determination of representative and precise BAFs for mercury in fish from large rivers necessitates collecting large and approximately equal numbers of fish and aqueous methyl mercury samples over a seasonal cycle from the entire area and all habitats to be represented by the TMDL.

Download or read book Index Veterinarius written by and published by . This book was released on 2004 with total page 1312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biogeochemistry of Wetlands written by K. Ramesh Reddy and published by CRC Press. This book was released on 2022-09-10 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: The globally important nature of wetland ecosystems has led to their increased protection and restoration as well as their use in engineered systems. Underpinning the beneficial functions of wetlands are a unique suite of physical, chemical, and biological processes that regulate elemental cycling in soils and the water column. This book provides an in-depth coverage of these wetland biogeochemical processes related to the cycling of macroelements including carbon, nitrogen, phosphorus, and sulfur, secondary and trace elements, and toxic organic compounds. In this synthesis, the authors combine more than 100 years of experience studying wetlands and biogeochemistry to look inside the black box of elemental transformations in wetland ecosystems. This new edition is updated throughout to include more topics and provide an integrated view of the coupled nature of biogeochemical cycles in wetland systems. The influence of the elemental cycles is discussed at a range of scales in the context of environmental change including climate, sea level rise, and water quality. Frequent examples of key methods and major case studies are also included to help the reader extend the basic theories for application in their own system. Some of the major topics discussed are: Flooded soil and sediment characteristics Aerobic-anaerobic interfaces Redox chemistry in flooded soil and sediment systems Anaerobic microbial metabolism Plant adaptations to reducing conditions Regulators of organic matter decomposition and accretion Major nutrient sources and sinks Greenhouse gas production and emission Elemental flux processes Remediation of contaminated soils and sediments Coupled C-N-P-S processes Consequences of environmental change in wetlands# The book provides the foundation for a basic understanding of key biogeochemical processes and its applications to solve real world problems. It is detailed, but also assists the reader with box inserts, artfully designed diagrams, and summary tables all supported by numerous current references. This book is an excellent resource for senior undergraduates and graduate students studying ecosystem biogeochemistry with a focus in wetlands and aquatic systems.

Download or read book Water Quality Assessments written by Deborah V Chapman and published by CRC Press. This book was released on 1996-08-22 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt: This guidebook, now thoroughly updated and revised in its second edition, gives comprehensive advice on the designing and setting up of monitoring programmes for the purpose of providing valid data for water quality assessments in all types of freshwater bodies. It is clearly and concisely written in order to provide the essential information for all agencies and individuals responsible for the water quality.

Download or read book Ecology and Management of a Forested Landscape written by John Kilgo and published by . This book was released on 2005-06-15 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book tells the story of fifty years of restoration and management of the forested landscape of the Savannah River Site, a 310-square-mile tract of land in the coastal plain of South Carolina that has been closed to the public for more than five decades. Ecology and Management of a Forested Landscape presents for the first time a complete synthesis and summary of information on the Savannah River Site, providing a detailed portrait of the plant and animal populations and communities on the site and the effects on them of fifty years of management practices." -- WEBSITE.

Download or read book Migratory Fishes of South America written by Joachim Carolsfeld and published by IDRC. This book was released on 2003 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mammals and Birds as Bioindicators of Trace Element Contaminations in Terrestrial Environments written by Elżbieta Kalisińska and published by Springer. This book was released on 2019-03-01 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt: The population explosion that began in the 1960s has been accompanied by a decrease in the quality of the natural environment, e.g. pollution of the air, water and soil with essential and toxic trace elements. Numerous poisonings of people and animals with highly toxic anthropogenic Hg and Cd in the 20th century prompted the creation of the abiotic environment, mainly in developed countries. However, the system is insufficient for long-term exposure to low concentrations of various substances that are mainly ingested through food and water. This problem could be addressed by the monitoring of sentinels – organisms that accumulate trace elements and as such reflect the rate and degree of environmental pollution. Usually these are long-lived vertebrates – herbivorous, omnivorous and carnivorous birds and mammals, especially game species. This book describes the responses of the sentinels most commonly used in ecotoxicological studies to 17 trace elements.

Download or read book Bioindicators for Assessing Ecological Integrity of Prairie Wetlands written by Paul R. Adamus and published by . This book was released on 1996 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Lake Victoria written by Joseph L. Awange and published by Springer Science & Business Media. This book was released on 2006-08-18 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes a pioneering and unique work on Lake Victoria. It is the world’s second largest fresh-water lake and supports the livelihood of more than 30 million people. Surprisingly, there has been no comprehensive book addressing its problems and potentials. Ecology, environmental pollution and resource management are some of the issues addressed by this comprehensive insight into the limitations, challenges and opportunities facing Lake Victoria.

Download or read book Fundamentals of Ecotoxicology written by Michael C. Newman and published by CRC Press. This book was released on 2019-11-27 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition is revised throughout and includes new and expanded information on natural resource damage assessment, the latest emerging contaminants and issues, and adds new international coverage, including case studies and rules and regulations. The text details key environmental contaminants, explores their fates in the biosphere, and discusses bioaccumulation and the effects of contaminants at increasing levels of ecological organization. Vignettes written by experts illustrate key themes or highlight especially pertinent examples. This edition offers an instructors' solution manual, PowerPoint slides, and supplemental images. Features: Adds all new discussions of natural resource damage assessment concepts and approaches Includes new vignettes written by leading guest authors Draws on materials from 2,500 cited sources, including 400+ new to this edition Adds numerous new entries to a useful glossary of 800+ terms Includes a new appendix discussing Brazilian environmental laws and regulations added to existing appendices outlining U.S., E.U., Chinese, Australian, and Indian environmental laws Fundamentals of Ecotoxicology: The Science of Pollution, Fifth Edition contains a broad overview of ecotoxicology and provides a basic understanding of the field. Designed as a textbook for use in introductory graduate or upper-level undergraduate courses in ecotoxicology, applied ecology, environmental pollution, and environmental science, it can also be used as a general reference for practicing environmental toxicologists.

Download or read book Measurement Analysis and Remediation of Environmental Pollutants written by Tarun Gupta and published by Springer Nature. This book was released on 2019-10-08 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses contamination of water, air, and soil media. The book covers health effects of such contamination and discusses remedial measures to improve the situation. Contributions by experts provide a comprehensive discussion on the latest developments in the detection and analysis of contaminants, enabling researchers to understand the evolution of these pollutants in real time and develop more accurate source apportionment of these pollutants. The contents of this book will be of interest to researchers, professionals, and policy makers alike.

Download or read book Cadmium in the Aquatic Environment written by Jerome O. Nriagu and published by John Wiley & Sons. This book was released on 1987-08-12 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents a comprehensive account of current research on the chemistry and toxicology of cadmium in natural waters. Discusses the sources, distribution, and fate of cadmium in aquatic ecosystems, including coverage of the biocycling and exotoxicity of cadmium to materia and fresh water biota. A succinct review of the analytical chemistry of cadmium in natural waters is also included. The contributors emphasize general principles rather than comprehensive documentation, making this volume accessible to a wide audience. The technical information helps provide the scientific rationale needed in the continuing effort to establish water quality criteria and standards for cadmium.