The complexity of ecosystems forms perhaps the greatest challenge for natural science. Even the first step to comprehensive analysis, namely a survey of the participating species, often forms a major obstacle. This makes it understandable that ecologists try to abstract general principles from the interrelationships of the multitude of species for use in their efforts to investigate ecosystem dynamics. Such 'unifying concepts' were the main theme of the 'First International Congress of Ecology' organized in The Hague in September 1974 by the International Association of Ecology (INTECOL), under the auspices of the Division of Environmental Biology of the International Union of Biological Sciences (IUBS). This book contains the papers presented at the plenary sessions of the Congress and a summary of the discussions engendered by them. At the Congress over 800 ecologists from many countries, representing diverse disciplines such as limnology, botany, zoology, microbiology, agriculture, met together for a week. The study of ecosystem dynamics depends on mutual understanding and close cooperation, and to stimulate an integrated approach a number of main speakers were invited to contribute papers on notions such as energy flow, productivity, diversity, stability and maturity from different points of view. These invited papers were presented at the morning plenary sessions, followed by discussions.

First published in 1980, this important book brings together the results of worldwide research (from the tropics to the Arctic) to determine the relative productivity of different freshwater environments, especially lakes. The investigations are presented in a comparative manner and the underlying causes considered. In addition this book is a useful summary of the extensive work done in Eastern Europe and the former Soviet Union and it makes these results available to a wider audience. The many authors are internationally recognized authorities and their syntheses are based on special studies of over ninety sites around the world during the 10 years of the IBP investigations, as well as on published material.

The result of compiling widely scattered research on fish in tropical rivers, lakes and seas. A comprehensive overview of the ecology of fish communities in freshwater as well as marine environments.