Download or read book Mercury Cycling in a Remote Boreal Drainage Basin written by Gretchen Lynne Lescord and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The consumption of freshwater fish and seafood is the main source of mercury (Hg), a widespread neurotoxic pollutant, in humans, a fact which has sparked decades of research on Hg cycling in aquatic systems. More specifically, the formation and bioaccumulation of methylmercury (MeHg) is of particular importance because it biomagnifies through aquatic food webs, resulting in relatively high levels in predatory fish despite typically low concentrations in the surrounding water. The main goal of this thesis was to assess how various watershed-level processes affect Hg bioaccumulation and biomagnification through freshwater food webs across the relatively pristine Attawapiskat Drainage Basin (ADB) in the remote Far North of Ontario. This watershed overlaps with the mineral-rich region known as the "Ring of Fire" which is expected to be heavily developed in the coming decades, likely altering the physico-chemical environments of surrounding lakes and rivers. In total, 58 lakes and river sites across the ADB were sampled for surface water quality, aquatic macroinvertebrates, and fish from 2014 to 2016. Water samples were analyzed for 39 chemical parameters including total Hg (THg; the sum of all Hg species) and MeHg concentrations ([MeHg]). Biotic samples were analyzed for [THg] and/or [MeHg], as well as carbon and nitrogen stable isotope ratios, which are indicative of an animal's food web position. In Chapter 1 of this thesis, I provide an overview of our current knowledge on Hg cycling in aquatic systems of the boreal region. In Chapter 2, I present an extensive assessment of the chemical, physical, and ecological gradients across the ADB, and an analysis of the relationships between Hg and these environmental gradients. I determined that less productive systems with higher concentrations of dissolved organic matter (DOM) had higher aqueous and biotic [Hg]. In Chapter 3, I examined how changes in the quality of DOM across the ADB relate to [Hg] in water and biota. Findings from this study suggest that more labile DOM complexes enhance MeHg bioaccumulation into food webs, while systems with more humic and aromatic DOM had higher aqueous total [Hg]. The fourth chapter critically examined the speciation of Hg in fish from across the ADB and showed substantially lower percentages of MeHg (relative to total Hg) in muscle of smaller-sized fish, particularly those which feed on littoral-based food webs and had higher lipid content in their tissue. These novel findings challenge the general assumption, used in many biomagnification studies and consumption guidelines, that all fish muscle tissue has > 95% MeHg. Finally, in Chapter 5, I discuss the implications of my research for subsistence fishers, specifically those from remote communities, where freshwater fish are important for both culture and sustenance. Here I developed some preliminary approaches to better communicating the risks and benefits of consuming fish when presenting fish tissue contaminant results in remote northern communities, including those in and around the ADB. Understanding the major influences on MeHg cycling is vital to properly monitoring the effects of industrial development (e.g., the Ring of Fire development) and climate change, which can greatly alter the physico-chemical environment of surrounding lakes and rivers. The results from my thesis indicate significant physical and chemical differences between waters in the two ecozones (i.e., the Boreal Shield and Hudson Bay Lowlands) across the ADB, presumably due to changes in bedrock geology and riparian characteristics. No other study, to my knowledge, has explored the effects of landscape position and the associated changes in physico-chemical characteristics on Hg bioaccumulation, speciation, and biomagnification on such a large scale. My findings demonstrate that monitoring programs will need to effectively track changing nutrient concentrations, DOM characteristics, and Hg bioaccumulation patterns that vary across large spatial gradients.
Download or read book Biogeochemical Cycle of Mercury in Reservoir Systems in Wujiang River Basin Southwest China written by Xinbin Feng and published by Springer. This book was released on 2017-11-09 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an intensive study on the biogeochemical cycle of mercury in a river-reservoir system in Wujiang River Basin, the upper branch of the Yangtze River. Six reservoirs located in the mainstream of the Wujiang River and their corresponding inflow/outflow rivers were selected for inclusion in this study, which was conducted by researchers from the Institute of Geochemistry, Chinese Academy of Sciences. The concentration and distribution of Hg in reservoirs (the water column, sediment, sediment pore water), inflow/outflow rivers of reservoirs, and wet deposition in Wujiang River Basin were systematically investigated, and measurements were taken of the water/air exchange flux of gaseous elemental mercury (GEM). On the basis of the data gathered, a detailed mass balance of total mercury (THg) and methylmercury (MeHg) in the six reservoirs was developed. In addition, the book identifies the primary factors controlling Hg methylation in the river-reservoir system in Wujiang River Basin. The accumulation and bio-magnification of Hg species within food chains in reservoirs and human health risk of MeHg exposure through fish consumption are also included in this book.
Download or read book Peatland Biogeochemistry and Watershed Hydrology at the Marcell Experimental Forest written by Randall Kolka and published by CRC Press. This book was released on 2011-02-22 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Marcell Experimental Forest (MEF) in Minnesota serves as a living laboratory and provides scientists with a fundamental understanding of peatland hydrology, acid rain impacts, nutrient and carbon cycling, trace gas emissions, and controls on mercury transport in boreal watersheds. Its important role in scientific research continues to grow as t
Download or read book Mercury Cycling in a Wetland dominated Ecosystem written by Nelson J. O'Driscoll and published by Society of Environmental Toxicology & Chemistry. This book was released on 2005 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 The Ebro River Basin written by Damià Barceló and published by Springer Science & Business Media. This book was released on 2011-01-05 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Ebro is a typical Mediterranean river characterized by seasonal low flows and extreme flush effects, with important agricultural and industrial activity that has caused heavy contamination problems. This volume deals with soil-sediment-groundwater related issues in the Ebro river basin and summarizes the results generated within the European Union-funded project AquaTerra. The following topics are highlighted: Hydrology and sediment transport and their alterations due to climate change, aquatic and riparian biodiversity in the Ebro watershed, occurrence and distribution of a wide range of priority and emerging contaminants, effects of chemical pollution on biota and integration of climate change scenarios with several aspects of the Ebro’s hydrology and potential impacts of climate change on pollution. The primary objective of the book is to lay the foundation for a better understanding of the behavior of environmental pollutants and their fluxes with respect to climate and land use changes.
Download or read book Mercury Pollution Integration and Synthesis written by Carl J. Watras and published by CRC Press. This book was released on 1994-11-11 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains 57 chapters describing the results of original research and reviewing the state-of-the-science with respect to environmental mercury. Topics include analytical methodology, atmospheric cycling, freshwater and marine ecosystems, terrestrial processes, bioaccumulation, modeling, pollution and remediation, and human health and public policy.
Download or read book Environmental Chemistry and Toxicology of Mercury written by Guangliang Liu and published by John Wiley & Sons. This book was released on 2011-11-07 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the fundamentals, recent developments, and future research needs for critical mercury transformation and transport processes, as well as the experimental methods that have been employed in recent studies. The coverage discusses the environmental behavior and toxicological effects of mercury on organisms, including humans, and provides case studies at the end of each chapter. Bringing together information normally spread across several books, this text is unique in covering the entire mercury cycle and providing a baseline for what is known and what uncertainties remain in respect to mercury cycling.
Download or read book Mercury in the Biogeochemical Cycle written by Marc Marcotte and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 411 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nowadays, major environmental issues are the object of large public debates de spite the fact that scientific knowledge is often insufficient to draw unequivocal conclusions. Such is the case in the ongoing debate regarding the specific contri butions of anthropogenic greenhouse gas emissions and of natural climate changes to global warming. At least 10 to 20 years of additional observations will be re quired, before we will be able to conclude, with certainty, on this subject. In the mean time, and as directed by their immediate interests, people will continue to promote contradictory opinions. The media are, in part, responsible for perpetuat ing such debates in that they convey indiscriminately the opinion of highly credi ble scientists as that of dogmatic researchers, the latter, unfortunately too often expressing working hypotheses as established facts. Naturally, in a similarly mis informed manner, pressure groups tend to support the researcher whose opinions most closely represent either their particular ideological battles or their economic interests and, hence, in their own way, add further to the confusion and obscurity of the debate. Only a few years ago, mercury (Hg)contamination in hydroelectric reservoirs was the object of such media and social biases. At the time, analytical data used to support the discourse were themselves uncertain and numerous hypotheses, often times fanciful, were proposed and hastily "delivered" to the public.
Download or read book Environmental chemistry of mercury Sources pathways transformations and impact written by Ashu Dastoor and published by Frontiers Media SA. This book was released on 2024-01-29 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Global and Regional Mercury Cycles Sources Fluxes and Mass Balances written by W. Baeyens and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential themes in the biochemical cycling of mercury are the relative importance of anthropogenic versus natural sources, transformation and migration processes at the local, regional and global scale, global emission inventories of different mercury sources (both point and diffuse) of both natural and anthropogenic origin. In this regard, Siberia, with its vast territory and variety of natural zones, is of special interest in the global mercury cycle and in terms of the influence of geographical zones on source and sink terms in regional budgets. Siberia contains large areas of mercuriferous belts; natural deposits that emit mercury into the atmosphere and water. Siberian gold has been mined with the use of mercury since the early 1800s. But there, too, huge forest zones and vast areas of tundra and wetland (bogs) can act as efficient sinks for atmospheric mercury. Audience: Environmental scientists, legislators, politicians and the interested citizen wishing to gain a clear picture of the biogeochemical cycling of mercury.
Download or read book Mercury in the Environment written by Michael S. Bank and published by Univ of California Press. This book was released on 2012-05-31 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Mercury deposition and contamination is widespread and well documented, and it continues to be a public-health concern for certain sectors of the global human population in both developed and developing countries. This edited volume focuses on integrating the diverse sciences involved in the process of mercury cycling in the environment--from the atmosphere, through terrestrial and aquatic food webs, and human populations--to develop a comprehensive perspective on this important environmental pollutant. Using a systems-level approach, this book provides recommendations on mercury remediation, risk communication, education, and monitoring. In response to a growing need for understanding the cycling of this ubiquitous pollutant, the science of mercury has grown rapidly, expanding into several interdisciplinary fields and encompassing such disparate academic and scientific disciplines as biogeochemistry, economics, sociology, public health, decision sciences, physics, global change, and mathematics. Only recently have scientists really begun to establish more holistic approaches to studying mercury pollution, giving rise to investigations that have furthered the integration of a multi-tiered approach, especially by using chemistry, biology, and human health sciences collectively. The study of mercury pollution has produced a variety of contributions to domestic and international policies related to the management of mercury in the environment"-- Provided by publisher.
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 Mercury in the Environment written by Michael S. Bank and published by Univ of California Press. This book was released on 2012-05-31 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury pollution and contamination are widespread, well documented, and continue to pose a public health concern in both developed and developing countries. In response to a growing need for understanding the cycling of this ubiquitous pollutant, the science of mercury has grown rapidly to include the fields of biogeochemistry, economics, sociology, public health, decision sciences, physics, global change, and mathematics. Only recently have scientists begun to establish a holistic approach to studying mercury pollution that integrates chemistry, biology, and human health sciences. Mercury in the Environment follows the process of mercury cycling through the atmosphere, through terrestrial and aquatic food webs, and through human populations to develop a comprehensive perspective on this important environmental problem. This timely reference also provides recommendations on mercury remediation, risk communication, education, and monitoring.
Download or read book The Distribution and Speciation of Mercury in the Pearl River Drainage Basin Mississippi written by Adrian Coleman Green and published by . This book was released on 2000 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 and the Everglades A Synthesis and Model for Complex Ecosystem Restoration written by Curtis D. Pollman and published by Springer Nature. This book was released on 2020-11-28 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the final installation in a three-volume series synthesizing 30 years of mercury research in the Florida Everglades. The first part of this book evaluates the occurrence of trends in both biota mercury concentrations and atmospheric mercury deposition. Through both empirical and deterministic analyses, the likely drivers of biota trends are identified. These analyses help lay the predicate for devising an overall strategy to mitigate and manage the Everglades mercury problem. The book concludes with a model analysis of the likely benefits and uncertainty attendant with implementing the leading candidate strategy for best reducing the Everglades mercury problem.
