The papers deal with all aspects of lake management, corresponding to major sessions of the Symposium:
1) Lakes and Reservoirs as water supply sources;
2) Operational Limnology; new approaches;
3) Management driven research: case studies;
4) Nutrient cycling
5) Control factors of aquatic population dynamics

Lake Kinneret is Israel's only large freshwater lake and serves as the main reservoir for the National Water Carrier that provides almost a third of the country's water requirements and an even higher proportion of drinking water needs. Since 1968, the Yigal Allon Kinneret Limnological Laboratory has carried out basic and applied research aimed at understanding how present and future environmental conditions may affect water quality and how best to protect the lake ecosystem in an era of rapid regional development. Largely as a result of the monitoring and research efforts of Laboratory scientists, the management authorities (Israel Water Commission, the Kinneret Authority and Mekorot Water Company) have been able to maintain acceptable lake water quality over the years.

For over 30 years the Laboratory has fulfilled its mandate as ``caretaker of Lake Kinneret'' and in doing so has acquired an outstanding international reputation for innovative and significant research. As a result the laboratory has been involved in joint studies, exchange programs and training courses with many other countries, (including Australia, Belarus, Canada, Chili, China, Egypt, France, Germany, Hungary, Italy, Japan, Kenya, San Salvador, Sweden, Thailand, Turkmenistan, Ukraine, United Kingdom and the U.S.A). Laboratory scientists continue to search for environmentally acceptable solutions to the future water requirements of Israel and her neighbours as part of the evolving Middle East Peace Process.

Der umfangreiche Band enthält daher eine breite Palette an Themen. meist aus der aktuellen limnologischen Forschung. Schwerpunkte sind z. B. Seen und Talsperren als Reservoire für die Wasserversorgung, neue methodische Ansätze, Nährstoffzyklen sowie die Populationsdynamik. Es handelt sich um originale Forschungsbeiträge. Nur wenige Artikel haben Review-Charakter. wie die Arbeiten von BEN-MEIR (Water storage capacity in Israel). GOLDMAN (Management-driven limnological research) and Tri ZER (Control factors of planktonic Population dynamics in treshwater: a review). Ein Band, der gebündelt aktuelle limnoiogische Forschung bringt!

W. SCHÖNBORN

Limnologica 31 (2001), S. 184

Therefore it can be experienced even at the first looking-on, that this band is an exhaustive one. Everybody, who is interested in limnology, especially in algology, can read in this book about new methods and new approaches in these fields. Without highlighting any of these articles, we would like to remark that these progressive publications are of international interest, although certainly, much of them deal with the Lake Kinneret.

One can find here description on investigation, which solve practical problems of water utilising, too. Nowadays the management of lakes and water-bodies of other kind are widely and often negotiated points of view. Information and case studies about this topic are also available in this book. 264 figures - among them also coloured ones - and 64 tables make the certain reports more interesting to study and easier to understand. I recommend this very useful book for all limnologists, phycologists, and algologists working on aquatic environment all over the world.

K. SZABO

The diverse papers published from those presented at the Symposium were organized into five loose general categories:

Lakes and reservoirs as water supply sources. Seven papers address varied topics of the water storage capacities of Israel, effects of algae and cyanobacteria on wafer qualify, particularly, in relation to drinking water supplies, and the regulation of salinity sources to the wafer qualify of Lake Kinneret.

Operational limnology: New approaches. Studies presented in eleven papers address such varied topics as evaluating phytoplankton composition by delayed fluorescence excitation spectroscopy, spectral radiometer measurements for estimating phytoplankton pigment concentrations from direct in-lake spectral monitoring to close range and satellite imagery with potential for remote separation of different types of pigments, limitations of Secchi transparencies for estimating light attendance, limited success of zooplankton regulation by manipulations of fish predation, sediment sampling, and correlational modeling of circulation patterns in small lakes with couplings to sediment quality and benthos distributions.

Management driven research: Case studies. Six papers evaluated results of various management and restoration efforts among specific lake ecosystems. Treatments vary from general analyses to specific problems, such as river transport of sediments, physiological aspects of buoyancy in cyanobacteria, and the effects of reservoir water level fluctuations on macrophyte development and fish refuges. Nutrient cycling. A potpourri of nine papers addresses a diversity of subjects on nutrient fluxes, nutrient reservoirs, and regulation of nutrient turnover. In an adroit paper Hessen and Faafeng couple nutrient element ratios back to physiological limitations and carbon flux regulation. Other papers include dynamics of carbohydrates and combined amino acids, turnover rates of seston and carbon fluxes, regulation of sedimentation rates of phosphorus, bacterial chemoautotrophy, phosphorus-calcite interactions, and utilisation of organic phosphorus and nitrogen compounds.

Control factors of aquatic population dynamics. The concluding seven studies analyze fluctuations in plankton, largely phytoplankton, and potential causes for observed spatial and temporal changes. It is apparent that resource competition and predatorprey relationships dominate conventional views of regulation of plankton dynamics. That conventional dogma is deeply entrenched, as evidenced in the detailed review of Tilzer. Yet it is clear that great voids exist in our understanding of the highly dynamic controlling factors, in part related to continued invoking of the same factors that are repeatedly shown to be quantitatively inadequate to cause the observed dynamics. Constant reversion to empirical hypotheses may be adequate for initial rudimentary management strategies, but are totally inadequate for understanding of the complexities of regulation of metabolic and population dynamics that are essential for truly effective management of water quality. Those messages emerge strongly from the frustratingly inadequate answers of control.

The analyses of this eclectic compendium are consistently good and often excellent. Most are thorough, informative contributions to the discipline. Some analyses provoke stimulating insights into contemporary research queries. For example, stoichiometric analyses of elemental ratios formulate hypotheses and direction for essential physiological experimentation on communities. Furthermore, many of the nutrient flux and turnover analyses point to the essential chemical interactions that regulate availability independently of absolute quantities of nutrients and energy. Other important reinforcing studies emphasized again the significance of wind-induced hydrodynamics in sediment distribution, diagenesis, and their coupled biotic effects at multiple levels.

In summary, this compendium contains a wealth of peer-reviewed information most contributory to contemporary limnology. Although many papers address specific problems and phenomena of Lake Kinneret, most of the processes analyzed and conclusions are more widely applicable. Even though these papers of this journal series are not abstracted as widely in information services as is the case of contents of many conventional scientific journals, they are important contributions that should be recognized. The work is highly recommended for ecological research libraries.

ROBERT G. WETZEL

SILnews 34, Sept. 2001, p. 14/15