Gopal B., Junk W.J. & Davis J.A. (Eds). 2000 - Biodiversity in wetlands : assessment, function and conservation, Volume 1. Backhuys Publishers, Leiden, The Netherlands : 353 p. ISBN 90-5782-059-5. Dutch Guilders 196.00/US$ 98.00 - Review printed in Annls. Limnol., 37(2) : 165.

This remarkable work, published in 2 volumes, follows upon the Vth International Wetlands Conference, September 22-28, 1996, Perth, Australia. It wants to continue the discussions opened during this conference.

Two objectives are pursued : (1) to realise a synthesis including the variety of the recorded wetlands, of the state of our knowledge on the multiple aspects of the biodiversity in wetlands (2) to consider the means and techniques to be implemented to conserve and restore the world patrimony represented by wetlands in terms of biodiversity. The editor's expected result is to provide a common basis in order to stimulate and optimise further research.

In the introduction, the editors place the recent attention given to the biodiversity of wetlands in its international historic context and demonstrate, using quantitative examples, the important contribution of inland waters to global biodiversity. They insist about the considerable destruction of wetlands by human activities at the world level and point out our immobility for action on their subject despite the fact that we are aware of it since 1971 (International Ramsar Convention). Finally, they underline, by basing themselves on all the contributions of the book, the multiple dimensions of the wetland biodiversity as well as our poor knowledge on its ecological functions.

Follow fourteen articles with the objective to illustrate these dimensions. These give examples based on bacteria, plants and most of the animal groups (macroinvertebrates, fish, birds, mammals). They deal with various types of wetlands (mangroves, riverine floodplains, karst wetlands, seasonal wetlands) in some geographic regions of the world (tropical and neotropical régions, temperate regions, dry regions).

Most of the articles provide a thorough discussion, based on the own experience of the authors and on a solid bibliography. Results of numerous studies concerning species, habitats and functional diversity are discussed in order to understand factors and mechanisms governing the emergence, the preservation or the loss of biodiversity. Others articles present remarkable case studies which illustrate and support conclusions developed in the overviewing articles. Hence, this first volume already constitutes a mine of information and a good base for reflection for anyone interested in wetlands biodiversity.

The other main attraction of this work is the extent to which it treats questions about biodiversity conservation and wetlands restoration.

All the authors denounce the increasing destruction of wetlands by human activities, independently of their nature or geographic location. All also agree on the ecological, economic and cultural value of these wetlands and on the necessity to restore or protect them in order to conserve the world biodiversity. Half of the contributions include the author's opinion and recommendations about means of conservation to be implemented.

Both last articles are even completely dedicated to this problem. J.B Zedler's article (Restoration of biodiversity to coastal and inland wetlands) questions our real capability to conserve biodiversity using wetland restoration, as most efforts produce ecosystems that are less diverse than reference ecosystems. He makes the inventory of the difficulties encountered, difficulties often related to the functional complexity of wetlands. The author concludes that, considering our actual knowledge, prevent losses of natural habitat would be better to sustain biodiversity than attempt to repair damages. Research must before understand about factors responsible for a species being common or rare in a region. D.M. Bartley's article (International mechanisms for the conservation and sustainable use of wetlands) reviews the available international tools and highlights why they are not fully effective : overlapping of the tools due to a poor international coordination, lack of adapted national policies.

To conclude, the subject is extensively treated. Due to its handy size as well as to its sober and aesthetic presentation, this first volume is attractive. Due to the quality of its contents and the coordinative approach of the editors, it is a must.

The second volume to come will extend the geographical and typologic coverage of the examples. The editors plan to synthesise the discussions and conclusions of all the contributions (volume 1 and 2) in order to propose future common orientations to take in terms of research and conservation. For my part, I look forward to it impatiently.

Xavier-François GARCIA