The decision to build a nuclear power plant at Calvert Cliffs on the western shore of the Chesapeake Bay in southern Maryland resulted in a Iandmark legal decision (Calvert Cliffs Coordinating Committee vs Atomic Energy Commission) and began one ofthe mostintensive long-term studies ever carried out in an American estuarine system. In the pages that follow we describe the major results and findings from studies conducted over more than a decade by scientists from The Academy of Natural Seiences of Philadelphia (ANSP). These studies were designed to assess the potential effects that operation ofthe Calvert Cliffs Nuclear Power Plant (CCNPP) might have on the mid-portion of Chesapeake Bay. The approach taken was to study major biotic components of the system over an area and a time period sufficient to allow comparison of conditions between preoperational and operational periods within a sampling locality, and comparisons of conditions at reference sites with those at impact sites afterplant operations began. Elementschosen for detailed study included: species composition and production rates of major primary producers; water chemistry; zooplankton, benthos and finfish abundance and species composition; the abundance and growth rates of commercially important shellfish (clams, oysters and blue crabs); and the colonization sequences of invertebrates on artificial substrates.

The objective of this book is to review the physical and chemical characteristics of estuaries. The volume has been designed principally as a reference for scientists, but administers, managers, decision makers, and other professionals involved in some way with estuarine research can find value in the text.

This book arises from a workshop on the application of network analysis to ecological flow networks. The purpose is to develop a new tool for comparison of ecosystems, paying particular attention to marine ecosystems. After a review of the methods and theory, data from a variety of marine habitats are analyzed and compared. Readers are shown how to calculate such properties as cycling index, average path length, flow diversity, indices of ecosystem growth and development and the origins and fates of particular flows. This is a highly original contribution to the growing field of ecosystem theory, in which attention is paid to the properties of the total, functioning ecosystem, rather than to the properties of individual organisms. New insights are provided into the workings of marine systems.