PREFACE
On the occasion of the 75th anniversary of the Netherlands Society of Aquatic Ecology (NVAE) a symposium was held in Amsterdam in June 1996 on the theme 'Aquatic life in the marine and freshwater environment'. We are happy to publish in this issue of the Netherlands Journal of Aquatic Ecology two review papers presented at that symposium by professor B. Moss and professor W.J. Wolff. At the same symposium, the 'Dresscher prize' for the best written papers in the Volumes 27 and 28 was awarded. The jury chaired by Dr S. Parma selected the paper 'Estuarine gradients determining the quality of tidal marsh halophytes as host plants for endophagous insect larvae: experimental evidence' by M.A. Hemminga, J. van Soelen and W. Kiswara (Vol. 27: 377-382) and the paper 'A coded checklist and ecological indicator values of freshwater diatoms from the Netherlands' by H. van Dam, A. Mertens and J. Sinkeldam (Vol. 28: 17-133). During the last three years, the Netherlands Journal of Aquatic Ecology has evolved into an international journal. To further evolve and strengthen this development the Netherlands Society of Aquatic Ecology has agreed with Kluwer Academic Publishers to continue the journal under the name 'Aquatic Ecology'. From 1997, the new journal 'Aquatic Ecology' will be published by Kluwer Academic Publishers under the editorial responsibilities of the Netherlands Society of Aquatic Ecology. The Netherlands Journal of Aquatic Ecology did start in 1967 in Dutch as 'Mededelingen van de Hydrobiologische Vereniging'. In 1973, its name was changed into 'Hydrobiological Bulletin' and papers were published in English in two issues per year. In concert with a name-change of the 'Hydrobiologische Vereniging' into the 'Netherlands Society of Aquatic Ecology' in 1992, the present name 'Netherlands Journal of Aquatic Ecology' was introduced. In a period of 30 years the journal has developed from a scientific communication leaflet of the Society into an international journal with four issues per year. Dr Jaap Dorgelo was one of those who took the initiative to set up the 'Mededelingen' and performed as the editor-in-chief from the very beginning. The Society is very grateful to Dr Dorgelo for his continued dedication and his perseverance to bring the journal to the position where it is now. Therefore, at the Society's annual meeting of February 1997 Dr J. Dorgelo was appointed honorary member of the Netherlands Society of Aquatic Ecology. The Society furthermore gratefully acknowledges the other editors and the members of the advisory board for their contributions to the Netherlands Journal of Aquatic Ecology. For the new journal 'Aquatic Ecology', the task of editor-in-chief will be taken over by Dr R. Gulati and he will be assisted by the associate editors Dr K. Essink and Prof Dr N. de Pauw. Aad C. Smaal, President NVAE