Download or read book Seasonal and Spatial Variations in Methylmercury in the Water Column of Sulfate Impacted Lakes written by Logan Bailey and published by . This book was released on 2014 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Seasonal and Spatial Variations of Mercury Methylation and Methylmercury Decomposition in an Oligotrophic Northern Wisconsin Lake written by Eric T. Korthals and published by . This book was released on 1986 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The formation of methylmercury represents a potentially serious problem in aquatic ecosystems because of its toxicity and accumulation in aquatic biota. Elevated levels of mercury in edible fish have recently been reported for several lakes in Northern Wisconsin. The majority of mercury in fish tissue is in the methylated form, suggesting that biological mercury methylation is a key process regulating mercury levels in fish. Numerous studies have examined mercury methylation in aquatic ecosystems but most have addressed only net rates of methylmercury production. The net amount of methylmercury produced in the aquatic environment is dependent on both methylation and demethylation. Recent studies have examined the effects of pH on mercury methylation and demethylation in several lakes in Canada and Northern Wisconsin. However, little else is known about the relative rates of these simultaneous processes in aquatic ecosystems. The purpose of this study was to examine where and when the potential for methylation was the greatest in Lake Clara; to examine the products of microbial demethylation; and to examine the effects of acidification on methylation and demethylation. Microbial mercury methylation and methylmercury decomposition were examined in Lake Clara, an oligotrophic Northern Wisconsin seepage lake, using 203Hg(N03)2 and 14cH3Hgi, respectively. The primary sites for mercury methylation in Lake Clara were in the surficial sediments of the backwater area and the littoral-profundal transitionary zone. Mercury methylation in surficial sediments was greatest from mid-July through September. The potential for methylation in the water column and attached microbial communities was low; whereas, demethylation activity was substantially greater. Thus, the net rate of methylmercury production may be significantly affected by demethylation activity.
Download or read book Sulfate Reduction and Mercury Methylation Potential in the Sediments of Clear Lake CA written by Elizabeth Erin Mack and published by . This book was released on 1997 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1988 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biogeochemistry of Environmentally Important Trace Elements written by Yong Cai and published by . This book was released on 2003 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biogeochemistry of Environmentally Important Trace Elements discusses fate, transport, and transformation in soils, waters, and plants in biogeochemistry of environmentally important trace elements, with a focus on arsenic, mercury, and selenium.
Download or read book Spatial and Temporal Variation in Mercury Methylation in Sediment and Water of Farmington Bay of the Great Salt Lake Utah written by Abigail Rudd and published by . This book was released on 2010 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecosystem Responses to Mercury Contamination written by Reed Harris and published by CRC Press. This book was released on 2007-03-05 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: As rising levels of mercury in the environment pose an increasing threat of toxicity to humans and wildlife, several laws already call for industries to reduce mercury emissions at the source. Ecosystem Responses to Mercury Contamination: Indicators of Change outlines the infrastructure and methods needed to measure, monitor, and regulate the conce
Download or read book Environmental Toxicology and Chemistry written by and published by . This book was released on 2000 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sediment Flux and Photodegradation of Methylmercury in Two Boreal Drainage Lakes written by Patricia Sellers and published by . This book was released on 1997 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 1993 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sediment Flux and Photodegradation of Methylmercury in Two Boreal Drainage Lakes written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sulfate Differences Based on Wetland Physical Characteristics written by Sadie Libal and published by . This book was released on 2017 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This thesis is broken down into two chapters; chapter one looking at sulfate differences among wetland types and sulfate/methylmercury trends throughout the state of Minnesota. Water and sediment samples were collected from nine different wetland types and a riverine system. Wetlands were chosen within a ten-mile radius of one another. The study looked to determine factors driving differences in sulfate concentrations based off of wetland characteristics, spatial (within wetland) and temporal scales. Finally, statewide data from Minnesota Pollution Control Agency (MPCA) and Minnesota Department of Natural Resources (MN DNR) was utilized to look at spatial differences of both sulfate (in water) and methylmercury (in fish) within Minnesota. After looking at the various factors of potential sulfate differences between wetland types, the data suggests that proximity to development shows the greatest likelihood of being the significant factor determining sulfate concentrations within a wetland. Chapter two focuses on the tree swallows of Grand Portage National Monument (GRPO). Tree swallows have been proven proxies for piscivorous birds in other studies. Through the collection of tree swallow eggs we gained an understanding of the terrestrial mercury load in this area. Overall the data suggests that the tree swallows in Grand Portage hold a similar mercury body burdens to those studied previously in northern Minnesota (Voyageurs National Park (VOYA) and Agassiz wildlife refuge) and around the great lakes (69 sites, spread between Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, Pennsylvania and New York) which showed no outward decreased fitness, which is generally described by hatching success and survivorship to fledging. By comparing the Hg concentrations in tree swallows to concentrations known to decrease fitness, managers will be able to make decisions based off the data to determine where grant funding should be directed."--Abstract.
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 Water Quality for Ecosystem and Human Health written by Geneviève M. Carr and published by UNEP/Earthprint. This book was released on 2008 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document is intended to provide an overview of the major components of surface and ground water quality and how these relate to ecosystem and human health. Local, regional and global assessments of water quality monitoring data are used to illustrate key features of aquatic environments, and to demonstrate how human activities on the landscape can influence water quality in both positive and negative ways. Clear and concise background knowledge on water quality can serve to support other water assessments.
Download or read book Mercury as a Global Pollutant written by Donald B. Porcella and published by Springer. This book was released on 2014-08-23 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: ACKNOWLEDGEMENTS xiv PART I MERCURY AND HUMAN HEALTH B. WHEATLEY and S. PARADIS I Exposure of Canadian Aboriginal Peoples to Methylmercury 3-11 M. GIRARD and C. DUMONT I Exposure of James Bay Cree to Methylmercury during Pregnancy for the Years 1983-91 13-19 M. RICHARDSON, M. MITCHELL, S. COAD and R. RAPHAEL I Exposure to Mercury in Canada: A Multimedia Analysis 21-30 M. RICHARDSON, M. EGYED and D. J. CURRIE I Human Exposure to Mercury may Decrease as Acidic Deposition Increases 31-39 L. E. FLEMING, S. WATKINS, R. KADERMAN, B. LEVIN, D. R. AVYAR, M. BIZZIO, D. STEPHENS and J. A. BEAN I Mercury Exposure in Humans through Food Consumption from the Everglades of Florida 41-48 J. M. GEARHART, H. J. CLEWELL III, K. S. CRUMP, A. M. SHIPP and A. SILVERS I Pharmacokinetic Dose Estimates of Mercury in Children and Dose-Response Curves of Performance Tests in a Large Epidemiological Study 49-58 I. SKARE I Mass Balance and Systemic Uptake of Mercury Released from Dental Amalgam Fillings 59-67 J. DELLINGER, N. KMIECIK, S. GERSTENBERGER and H. NGU I Mercury Contamina tion of Fish in the Ojibwa Diet: I. Walleye Fillets and Skin-On versus Skin-Off Sampling 69-76 J. DELLINGER, L. MALEK and M. BEATTIE I Mercury Contamination of Fish in the Ojibwa Diet: II. Sensory Evoked Responses in Rats Fed Walleye 77-83 H. AKAGI, O. MALM, F. J. P. BRANCHES, Y. KINJO, Y. KASHIMA, J. R. D. GUIMARAES, R. B. OLIVEIRA, K. HARAGUCHI, W. C. PFEIFFER, Y.
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 Long Island Sound written by James S. Latimer and published by Springer Science & Business Media. This book was released on 2013-11-22 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. Ocean Commission Report identified the need for regional ecosystem assessments to support coastal and ocean management. These assessments must provide greater understanding of physical and biological dynamics than assessments at global and national scales can provide but transcend state and local interests. This need and timeliness is apparent for Long Island Sound, where a multi-state regional restoration program is underway for America’s most urbanized estuary. Synthesis of the Long Island Sound ecosystem is needed to integrate knowledge across disciplines and provide insight into understanding and managing pressing issues, such as non-point sources of pollution, coastal development, global climatic change, and invasive species. Currently, there is a need for a comprehensive volume that summarizes the ecological and environmental dynamics and status of Long Island Sound and its myriad ecosystems. It has been 30 years since a comprehensive summary of Long Island Sound was prepared and 50 years since the pioneering work of Gordon Riley. Major advances in estuarine science are providing new insights into these systems, and yet, the condition of many estuaries is in decline in the face of continuing coastal development. There is an opportunity to lay a foundation for integrative coastal observing systems that truly provide the foundation for improved decision-making. This book will provide a key reference of our scientific understanding for work performed over the past three decades and guide future research and monitoring in a dynamic urbanized estuary.
