Organic Acids In Aquatic Ecosystems

Organic Acids in Aquatic Ecosystems E. M. Perdue E. T. Gjessing Editors This volume consists of background papers and reports on discussions focused on identifying major processes that cause spatial and temporal variability in properties and concentrations of organic acids in aquatic ecosystems. Scientists in aquatic chemistry, environmental chemistry, soil chemistry, organic geochemistry, water treatment technology, forest ecology, and stream ecology collectively address four major questions: What is the composition of organic acids and how are they characterized? How are acid-base properties of "DOC" measured and modeled and how do they affect aquatic ecosystems? How do organic acids interact with solutes, surfaces, and organisms? What are the temporal and spatial variations of organic acids at the ecosystem level? This volume provides an up-to-date assessment of the state of knowledge of organic acids in aquatic ecosystems and identifies promising areas of new research that deserve the attention of all scientists who study chemical and biological processes in natural waters, where the importance of organic acids in such processes is not yet fully recognized.

Overviews of the source, supply and variability of DOM, surveys of the processes that mediate inputs to microbial food webs, and syntheses consolidating research findings provide a comprehensive review of what is known of DOM in freshwater. This book will be important to anyone interested in understanding the fundamental factors associated with DOM that control aquatic ecosystems."--BOOK JACKET.

Acidic deposition and its effect on aquatic ecosystems have become major scientific and public policy issues in the United States since the early 1970s, and many diverse studies have been completed. This book is the first comprehensive, integrated synthesis of available information on current and potential effects of acidic precipitation on lakes and streams in geographic regions with a high number of low-alkalinity surface water from the Adirondacks and the Southern Blue Ridge to the Upper Midwest to the Rocky Mountains, the Sierra Nevada, and the Cascades. Written by leading authors, the book examines the current status of water chemistry and characterizes the processes controlling water chemistry on a regional basis by using and comparing high-quality data sets. Methods for the assessment of long-term changes in water chemistry and their effects in fish and other biota are also presented. The book amply illustrates the substantial diversity among geographical regions with respect to the nature of surface waters and the complexity of their response to acidic deposition. This volume will be of great interest to researchers in limnology, aquatic ecology, environmental chemistry, hydrology, and atmospheric sciences. It will also serve as an important reference for environmental managers and policy makers.

Humic substances occur in all kinds of aquatic systems, but are particularly important in northern, coniferous areas. They strongly modify the aquatic ecosystems and also constitute a major problem in the drinking water supply. This volume covers all aspects of aquatic humic substances, from their origin and chemical properties, their effects on light and nutrient regimes and biogeochemical cycling, to their role regarding organisms, productivity and food web organization from bacteria to fish. Special emphasis is paid to carbon cycling and food web organization in humic lakes, but aspects of marine carbon cycling related to humus are treated as well.

This textbook provides a unique and thorough look at the application of chemical biomarkers to aquatic ecosystems. Defining a chemical biomarker as a compound that can be linked to particular sources of organic matter identified in the sediment record, the book indicates that the application of these biomarkers for an understanding of aquatic ecosystems consists of a biogeochemical approach that has been quite successful but underused. This book offers a wide-ranging guide to the broad diversity of these chemical biomarkers, is the first to be structured around the compounds themselves, and examines them in a connected and comprehensive way. This timely book is appropriate for advanced undergraduate and graduate students seeking training in this area; researchers in biochemistry, organic geochemistry, and biogeochemistry; researchers working on aspects of organic cycling in aquatic ecosystems; and paleoceanographers, petroleum geologists, and ecologists. Provides a guide to the broad diversity of chemical biomarkers in aquatic environments The first textbook to be structured around the compounds themselves Describes the structure, biochemical synthesis, analysis, and reactivity of each class of biomarkers Offers a selection of relevant applications to aquatic systems, including lakes, rivers, estuaries, oceans, and paleoenvironments Demonstrates the utility of using organic molecules as tracers of processes occurring in aquatic ecosystems, both modern and ancient

Organisms in aquatic ecosystems; Functions of aquatic environments; Dynamics of organic materials and microorganisms.