INTRODUCTION 



The papers which make up this volume were presented at a conference 

 held June 18 and 19, 1959 at the Pymatuning Laboratory. The focal point 

 of the conference and of this publication is encompassed in the title Ecology 

 of Algae . The emphasis in the papers is on fresh-water algae but several of 

 them present data from marine situations and implications can be extended 

 to this related field. 



Stimulation for many of the recent developments in our understanding 

 of algae has come from outside the traditional boundaries of botanical 

 sciences. Much has been contributed from those areas of ecology concerned 

 with the hydrosphere, limnology and oceanography. The emphasis on the role 

 of algae as the primary producers in aquatic ecosystems has resulted in a 

 great deal of work on the physiology of algae. Certain problems of engineers 

 concerned with sewage disposal, mass culture, and space travel have also 

 been a great stimulus to algal studies. 



The ecology of algae is here considered from the standpoint of ecological 

 phycology i .e. , we are interested in algae and their environmental relation- 

 ships. These algal-environment interactions may be viewed from the traditional 

 descriptive approach or they may be dealt with experimentally, either in terms 

 of changes occurring in the environment due to the algae or in terms of changes 

 that occur in the algae as a response to the environment. 



The fact that algae are able to alter decisively the biotic factors of their 

 environment, is brought out in the papers by Dr. Prescott and Dr. Hartman. 

 Dr. Blum and Dr. Whitford present a picture of the occurrence and composition 

 of algal communities in various ecological situations. Dr. Bartsch dwells on 

 the functional changes or processes that occur in a unique algal community. 

 Dr. Ryther continues this approach by presenting the results of algal activities 

 in terms of productivity, which is, to many ecologists, the philosopher's 

 stone that will provide understanding of the ecosystem. Dr. Provasoli shows 

 what may be necessary in an environment in order for growth and development 

 of algal communities to occur . 



It is obvious that time did not permit a full exploration of the ecology 

 of algae, even to the limited extent that the present development of the field 

 would permit . 



