MANAGEMENT AND ECOLOGY OF FRESH-WATER PLANTS - PROCEEDINGS OF THE 9THINTERNATIONAL-SYMPOSIUM ON AQUATIC WEEDS, EUROPEAN-WEED-RESEARCH-SOCIETY - PREFACE

Attendance at the 9th International Symposium on Aquatic Weeds, held i n Dublin in 1994, by 270 delegates from 35 different countries demonst rated the continuing interest in the management and ecology of freshwa ter plants. The relative importance of the various topics covered in t his meeting is compared with that of the previous symposia (1967-1990) for which published proceedings are available. A shift of interest aw ay from aquatic weed control towards ecology, plant-environment intera ctions and distribution is noted and demonstrates a growing recognitio n of the need for aquatic plant management. The interest in physical c ontrol has remained constant (5-12% of papers) whilst the interest sho wn in biological control over the period 1971 to 1982 has not been sus tained in recent symposia. The international nature of the symposia ha s increased over the years with papers published rising from eight cou ntries in the 1967, 1971 and 1974 symposia to 23, 18 and 20 in the las t three. Consistent numbers of contributions have been made by delegat es from the Netherlands, the Czech Republic and the United Kingdom wit h a significant and sustained increase since 1967 from the United Stat es of America.