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.