Estuaries and Wetlands are important coastal resources which are subject to a great deal of environmental stress. Dredging, construction, creation of intertidal wetlands, regulation of fresh water flow, and pollution are just a few of the activities which affect these coastal systems. The need to predict the effects of these perturbations upon ecosystem dynamics, particularly estuarine fisheries, as well as on physical effects, such as sedimentation and salt intrusion, is of paramount importance. Prediction requires the use of models, but no model is likely to be satisfactory unless fundamental physical, chemical, sedimentological, and biological processes are quantitatively understood, and the appropriate time and space scales known. With these considerations in mind, the Environmental Laboratory, U. S. Army Engineer Haterways Experiment Station,* Vicksburg, Mississippi, sponsored a workshop on "Estuarine and Wetland Processes and Water Quality Modeling" held in New Orleans, June 1979. The contents of this volume have been selected from the workshop papers. The resulting book, perhaps more than any other symposium proceed ings on estuaries and wetlands, attempts to review important pro cesses and place them in a modeling context. There is also a distinct applied tinge to a number of the contributions since some of the research studies were motivated by environmental assessments. The difference in title between this volume and the workshop re flects more accurately the contents of the published papers.

Estuaries and Wetlands are important coastal resources which are subject to a great deal of environmental stress. Dredging, construction, creation of intertidal wetlands, regulation of fresh water flow, and pollution are just a few of the activities which affect these coastal systems. The need to predict the effects of these perturbations upon ecosystem dynamics, particularly estuarine fisheries, as well as on physical effects, such as sedimentation and salt intrusion, is of paramount importance. Prediction requires the use of models, but no model is likely to be satisfactory unless fundamental physical, chemical, sedimentological, and biological processes are quantitatively understood, and the appropriate time and space scales known. With these considerations in mind, the Environmental Laboratory, U. S. Army Engineer Haterways Experiment Station,* Vicksburg, Mississippi, sponsored a workshop on "Estuarine and Wetland Processes and Water Quality Modeling" held in New Orleans, June 1979. The contents of this volume have been selected from the workshop papers. The resulting book, perhaps more than any other symposium proceed ings on estuaries and wetlands, attempts to review important pro cesses and place them in a modeling context. There is also a distinct applied tinge to a number of the contributions since some of the research studies were motivated by environmental assessments. The difference in title between this volume and the workshop re flects more accurately the contents of the published papers.

This report summarizes the proceedings of a workshop entitled 'Wetland and Estuarine Processes and Water Quality Modeling, ' held on 18-20 June 1979 in New Orleans, Louisiana. The workshop was organized by Science Applications, Inc. (SAI), under the sponsorship of the U.S. Army Engineer Waterways Experiment Station (WES) as part of the Corps of Engineers' Environmental Impact Research Program. In addition, this report includes recommendations for possible future research that emerged as a result of the presentations and discussions held during the workshop and two other studies performed under the contract: a survey of marine wetland and estuarine water quality and ecological problems in Corps of Engineers Field Offices; and a survey and review of published literature in the fields of hydrodynamics, water quality, and ecosystem modeling as applied to estuaries, coastal bays, and salt marshes. (Author).

The study of wetlands is a relatively new field and the modelling of these systems is still in its formative stages. Nevertheless, the editors felt compelled to assemble this volume as a first statement of the state of the art of modelling approaches for the quantitative study of wetlands. A global approach has been adopted in this book, not only by including a wide geographic distribution of wetlands, but also by including papers on both freshwater and saltwater wetlands. Wetlands are defined as systems intermediate between aquatic and terrestrial ecosystems, and include ecosystems under a wide range of hydrologic and ecologic conditions. The wetland types discussed in this book reflect that heterogeneity, ranging from intermittently flooded wet meadows to permanently flooded shallow reservoirs and lakes. Also included are modelling examples from coastal salt marshes, shallow estuaries, mesotrophic bogs, reedswamps, forested swamps, and regional wetlands. In summary, the book presents ecological modelling as a tool for management of these sensitive ecosystems, and for studying their structure and function. Each chapter has extensive references related to the modelling approach and wetland type discussed. It will be useful for wetland scientists and managers, and could also serve as a supplemental text on courses in wetland ecology.