Download or read book Stable Isotopic Composition and Phosphorus Concentration in Sediment from Two Southern California Lakes written by Simone Claire Boudreau and published by . This book was released on 2015 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excessive nutrient loading to lakes reduces water clarity, degrades biological habitat, limits light penetration, and often results in anoxia. Increased watershed urbanization is a major contributing factor of externally loaded nutrients. But even in lakes that have successfully reduced external nutrient loading rates, high nutrient concentrations may persist due to internal nutrient recycling within lake sediments. Internal phosphorus (P) cycling dynamics are a balance between sedimentation, which depends on the mineralization rate of settling organic matter; diagenetic processes within the sediment after deposition; and remobilization of P after deposition, which depends on mobile P content and elemental composition of the sediment. The interplay between these processes determines whether phosphorus is recycled or sequestered in the sediment, as well as how long it remains bioavailable. Measurement of the stable isotopes of carbon and nitrogen in sediment have enabled assessment of the sources and degree of cycling of organic matter, which is important in controlling P burial and release. In this study, stable isotopic composition, elemental composition, and phosphorus forms in the sediment from two southern California lakes that are impaired due to nutrients are assessed to determine how dynamic hydrologic conditions and management actions have influenced water and sediment quality in order to gain insight into how sediment properties and biogeochemical processes respond to varying conditions in each lake. The results of the study provide a comprehensive understanding of the sedimentological processes occurring in the lakes, which is imperative to accurately predict eutrophication trajectories and the impact that future events will have on water quality in order to develop the most effective nutrient mitigation strategies.
Download or read book Tracking Environmental Change Using Lake Sediments written by William M. Last and published by Springer Science & Business Media. This book was released on 2006-04-11 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theory Instrumentation NIR analysis of sediment samples Uses of NIRS in palaeolimnology Future perspectives Summary References Fly-ash particles. Neil Rose 319 12. Introduction A brief history Methods of extraction and enumeration Temporal distribution Spatial distribution Source apportionment The future Summary Acknowledgements References Part III: Stable Isotope Techniques 13. Application of stable isotope techniques to inorganic and biogenic carbonates. Emi Ito 351 Introduction Nomenclature and systematics of lake-water Mg/Ca and Sr/Ca ratios of lake-water of dissolved inorganic carbon (DIC) Carbonates in lake-sediments Mollusks Ostracodes Charaphytes Isotope analysis Preparation of carbonate samples for isotope analysis Conclusions Summary Acknowledgments References 14. Carbon and oxygen isotope analysis of lake sediment cellulose: methods and applications. Brent B. Wolfe, Thomas W. D. Edwards, Richard J. Elgood & Kristina R. M. Beuning 373 xi Introduction Stable isotope tracers in lake Historical development Methods Key criteria for paleohydrologic reconstruction Applications Future research directions Summary Acknowledgements References Nitrogen isotopes in palaeolimnology. Michael R. Talbot 15. 401 Introduction Nitrogen in lakes: forms and distribution Nitrogen isotopes Nitrogen isotope studies in palaeolimnology: sampling and measurement Some examples Closing remarks Summary Acknowledgments References Glossary, acronyms and abbreviations 441 Index 493 xiii PREFACE The explosive growth of paleolimnology over the past two decades has provided impetus for the publication of this series of monographs detailing the numerous advances and new techniques being applied to the interpretation of lake histories. This is the second volume in the series and deals mainly with physical and geochemical analytical techniques.
Download or read book Internal Loading of Nutrients in Three Southern California Lakes written by Elisha Marie Wakefield and published by . This book was released on 2001 with total page 170 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 1991 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lake Sediments as Evidence of Natural and Human induced Environmental Change from California and Nevada written by Liam Michael Reidy and published by . This book was released on 2013 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focuses on the history of natural and human-induced environmental change as recorded in the sediments of two lakes: Mountain Lake in the Presidio National Park, San Francisco, California and Big Soda Lake, near Fallon, Churchill County, Nevada. The records of these lakes examined in this study cover approximately the last 2,000 years. Sediment cores from the lakes were dated with radiocarbon, lead-210, plutonium 240/239, tephrachronology, and the first appearance of non-native pollen types. The cores were analyzed to determine changes in stable isotopes (carbon and oxygen), sediment chemistry, fossil pollen, magnetic susceptibility, organic content, and brine shrimp cyst concentrations. Big Soda Lake has been the subject of scientific investigation since the 19th Century and two famous scientists have previously worked at the site. First, the geologist, Israel Russell explored the lake in 1882 as part of his work on Pleistocene Lake Lahontan and provided the first scientific report on the lake. Later in 1933, Evelyn Hutchinson, the famous Yale limnologist, provided the first detailed limnological report for the lake. More recently in the 1980's, the lake has been studied by scientists from the United States Geological Survey. However, prior to the research reported on here, very little was known of the history of the lake or to what extent its sediments contained a useful record of environmental change. The sediments of Big Soda Lake provide clear evidence for both natural and human-induced environmental change during the past 1600 years. The climate record developed from the analyses of stable isotopes of oxygen and carbon, sediment chemistry, and the concentrations of brine shrimp cysts show several significant shifts in climate. The early part of the record from A.D. 400-850 is period marked by a fluctuating climate, with alternating wet/dry phases each lasting several decades each (40-60 years). During the period known as the Medieval Climate Anomaly (MCA)(A.D. 850-1400), we observe at least two relatively dry periods from A.D. 850-1150 and A.D. 1260-1400. Between the two dry phases, there is a pronounced wet period from A.D. 1150-1260. This wet period matches fairly well with evidence presented in other paleoenvironmental studies in the western Great Basin. During the Little Ice Age (LIA), the evidence indicates that the Big Soda Lake area was not always colder and/or wetter, but that it was in fact drier and perhaps warmer from A.D. 1400-1700 than it had been in the previous millennium. Pronounced dry phases were observed around A.D. 1400, A.D. 1500 and A.D. 1650. The wettest period during the LIA came between A.D. 1750-1800. The human impact record at Big Soda Lake developed from the analyses of stable isotopes of oxygen and carbon, sediment chemistry, and the concentrations of brine shrimp cysts show several dramatic changes in and around the lake since Anglo American settlement of the area began, in the 1850's. Several human impacts have been identified, including regional mining activity, soda salt extraction from the lake, and irrigation induced rising groundwater levels in the last century. Two of these events have dramatically impacted the lake in that time. Firstly, the development of a commercial soda manufacturing and processing facility at the lake beginning in 1875 until the early 20th century; and secondly, the development of irrigation agriculture which led to an 18 m rise in lake level in the first few decades of the twentieth century. The sediments at Mountain Lake provide evidence of unprecedented heavy metal contamination at the San Francisco Presidio during the past 60 years. The lake evidence is consistent with local land-use changes initiated by the arrival of Europeans in the area after 1776 and the construction of California State Highway 1 adjacent to the lake in the late 1930's. The study shows how small water bodies alongside roads can concentrate heavy metals and demonstrates the need for careful scientific investigation of sediments earmarked for dredging to determine what if any contaminants are present. A key outcome of the Mountain Lake research carried out as part of this dissertation was that in the Fall of 2011 a Federal judge ordered the California Department of Transportation (Caltrans) to pay 13.5 million dollars to the Presidio Trust so that the contaminated sediments could be removed and further run-off from the road be prevented from entering the lake.
Download or read book Stable Isotopic Variations of Meteoric Water in Southwestern California written by Daniel Patrick Rodoni and published by . This book was released on 1993 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stable Isotopic Composition of Total Organic Carbon in Bottom Sediments of Lake Baikal as a Proxy for Paleoclimatology written by Alexander A. Prokopenko and published by . This book was released on 1997 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Phosphorus Uptake and Release by Lake Ontario Sediments written by Roger T. Bannerman and published by . This book was released on 1975 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Benthic Oxygen and Phosphorus Dynamics in Castle Lake California written by Peter Austin Neame and published by . This book was released on 1975 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Environmental Isotope Geochemistry written by Mark Baskaran and published by Springer Science & Business Media. This book was released on 2011-10-13 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applications of radioactive and stable isotopes have revolutionized our understanding of the Earth and near-earth surface processes. The utility of the isotopes are ever-increasing and our sole focus is to bring out the applications of these isotopes as tracers and chronometers to a wider audience so that they can be used as powerful tools to solve environmental problems. New developments in this field remain mostly in peer-reviewed journal articles and hence our goal is to synthesize these findings for easy reference for students, faculty, regulators in governmental and non-governmental agencies, and environmental companies. While this volume maintains its rigor in terms of its depth of knowledge and quantitative information, it contains the breadth needed for wide variety problems and applications in the environmental sciences. This volume presents all of the newer and older applications of isotopes pertaining to the environmental problems in one place that is readily accessible to readers. This book not only has the depth and rigor that is needed for academia, but it has the breadth and case studies to illustrate the utility of the isotopes in a wide variety of environments (atmosphere, oceans, lakes, rivers and streams, terrestrial environments, and sub-surface environments) and serves a large audience, from students and researchers, regulators in federal, state and local governments, and environmental companies.
Download or read book Stable isotope studies on Mono Lake California 1 Delta18O in lake sediments as proxy for climatic change during the last 150 years written by H.-C. LI 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 Selected Water Resources Abstracts written by and published by . This book was released on 1991 with total page 1210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Publications of the Geological Survey written by Geological Survey (U.S.) and published by . This book was released on 1984 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Concentration and Isotopic Composition of Carbon in Marine Sediments Affected by a Sewage Discharge written by Edward P. Myers and published by . This book was released on 1974 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Practical Guidelines for the Analysis of Seawater written by Oliver Wurl and published by CRC Press. This book was released on 2009-06-09 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: As we discover more about the role of the ocean in global changes and identify the effects of global change on the ocean, understanding its chemical composition and processes becomes increasingly paramount. However, understanding these processes requires a wide range of measurements in the vast ocean, from the sea surface to deep-ocean trenches, fr
Download or read book New Publications of the U S Geological Survey written by and published by . This book was released on 1984 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stable Isotope Ecology written by Brian Fry and published by Springer Science & Business Media. This book was released on 2007-01-15 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: A solid introduction to stable isotopes that can also be used as an instructive review for more experienced researchers and professionals. The book approaches the use of isotopes from the perspective of ecological and biological research, but its concepts can be applied within other disciplines. A novel, step-by-step spreadsheet modeling approach is also presented for circulating tracers in any ecological system, including any favorite system an ecologist might dream up while sitting at a computer. The author’s humorous and lighthearted style painlessly imparts the principles of isotope ecology. The online material contains color illustrations, spreadsheet models, technical appendices, and problems and answers.
