V. Ilmavirta – författare

The coverage of this book is wide, including papers ranging from microbiology to engineering sciences. The biology of waters is handled at both species and ecosystem levels. The geographical distribution of topics ranges from the tropics to northern temperate areas.

It is not so very long ago that botanical concensus abandoned the distinction that was drawn between Algae and Flagellata, the latter having been regarded by zoologists as a group of the Protozoa. Even today some colourless flagellates may find themselves occupying different locations in contrasting taxonomic schemes. However, modern developments in ecology have placed greater emphasis on functional attributes of organisms, and hydro biologists have certainly been in the forefront of such changes. Thus we find that flagellates are again the subject of controversy, not so much over their taxonomic position as over their functional position - their role in aquatic ecosystems. At the 22nd Congress of the International Association of Theoretical and Applied Limnology in Lyon, France in August 1983, we conceived the idea of a meeting to discuss ''Flagellates in Freshwater Ecosystems''. This idea was approved by the committee of SIL and we arranged for the meeting to take place during June 1986 at Lammi Biological Station (University of Helsinki) in Finland. Participants from nine countries enjoyed outstanding hospitality from the staff at the Station during a week of lectures, excursions and discussion ses­ sions. On behalf of the participants we express our thanks for the generous sponsorship received from the Maj and Tor Nessling Foundation, the Academy of Finland, the Finnish Ministry of Education, Lammi Biological Station and the Finnish Limnological Society.

Multiple use of natural waters and watersheds poses many practical problems, some of which are clearly limnological, relating for example to carrying capacities oflakes, deterioration of water quality and fisheries management. It is thus important to consider limnological aspects when making decisions in the field of water management. To further this attitude the Finnish Limnological Society considered ''Lakes and Water Management'' to be a suitable theme for the Society''s Jubilee Symposium, held in Helsinki on 22-23 September, 1980 at the Viikki Campus of the University of Helsinki, to mark the Society''s 30th Anniversary. The Finnish Limnological Society has arranged nationallimnological symposia everyone or two years. The papers presented at these symposia have been published in the series ''Limnologisymposion'' (in Finnish or Swedish, with short summaries in an internationally spoken language). Due to financial difficulties, the series was terminated as of the symposium in 1979. When preparing the 30th Anniversary of the Finnish Limnological Society, the Governing Board of the Society decided to arrange an international symposium on a theme relevant to modern limnology both in Finland and elsewhere. The selected results of the successful meeting on lakes and water management, which was attended by 220 people from 7 countries, are presented in this volume.

Multiple use of natural waters and watersheds poses many practical problems, some of which are clearly limnological, relating for example to carrying capacities oflakes, deterioration of water quality and fisheries management. It is thus important to consider limnological aspects when making decisions in the field of water management. To further this attitude the Finnish Limnological Society considered 'Lakes and Water Management' to be a suitable theme for the Society's Jubilee Symposium, held in Helsinki on 22-23 September, 1980 at the Viikki Campus of the University of Helsinki, to mark the Society's 30th Anniversary. The Finnish Limnological Society has arranged nationallimnological symposia everyone or two years. The papers presented at these symposia have been published in the series 'Limnologisymposion' (in Finnish or Swedish, with short summaries in an internationally spoken language). Due to financial difficulties, the series was terminated as of the symposium in 1979. When preparing the 30th Anniversary of the Finnish Limnological Society, the Governing Board of the Society decided to arrange an international symposium on a theme relevant to modern limnology both in Finland and elsewhere. The selected results of the successful meeting on lakes and water management, which was attended by 220 people from 7 countries, are presented in this volume.

Limnology is increasingly concerned with water supply and the relation of man to aquatic environments. Without the continued availability of pure water, all progress in technology and other fields of human life will be to no avail. The global problems concerning clear water are already extremely pressing. More limnology knowledge is needed to solve these problems. The responsibility of man to save water and to take more intensive care of the environment is raised in many of the papers, in this book. This emphasizes the necessary and unquestionable relevance of limnology to human society. Too often the abuse of water usage reflects the neglect of scientific results. Limnologists have a responsibility to ensure that administrators understand what is going on. The coverage of the book is wide, including papers on microbiology to engineering sciences. The biology of waters is handled at both species and ecosystem levels. The geographical distribution of topics ranges from the tropics to northern temperate areas. In fact, limnology is increasingly becoming a science which is, rightly, relevant to everyday life, not just an academic subject.