There is a growing need for appropriate management of aquatic plants in rivers and canals, lakes and reservoirs, and drainage channels and urban waterways. This management must be based on a sound knowledge of the ecology of freshwater plants, their distribution and the different forms of control available including chemical and physical, and biological and biomanipulation. This series of papers from over 20 different countries was generated from the tenth in the highly successful series of European Weed Research Society symposia on aquatic plant management, this being the tenth. It provides a valuable insight into the complexities involved in managing aquatic systems, discusses state-of-the-art control techniques and deals with patterns of regrowth and recovery post-management. Careful consideration is given to the use of chemicals, a practice which has come under scrutiny in recent years. Underpinning the development of such control techniques is a growing body of knowledge relating to the biology and ecology of water plants. The authorship of the papers represents the collective wisdom of leading scientists and experts from fisheries agencies, river authorities, nature conservation agencies, the agrochemical industry and both governmental and non-governmental organisations.

The loss to national economies resulting from excessive plant biomass has been appreciable and has put pressure on water managers to develop weed control procedures. The results from the most up-to-date research activities and field trials of leading aquatic plant scientists and managers in all five continents, aimed at resolving these weed problems, has been drawn together in this volume.

Biology and Control of Aquatic Plants: A Best Management Practices Handbook is the fourth edition of a handbook produced by the not for profit Aquatic Ecosystem Restoration Foundation (AERF). The mission of the AERF is to support research and development which provides strategies and techniques for the environmentally and scientifically sound management, conservation and restoration of aquatic ecosystems. One way the Foundation accomplishes this mission is by producing this handbook to provide information to the public regarding the benefits of aquatic ecosystem conservation and aquatic plant management. The first, second and third editions of this handbook became some of the most widely consulted references in the aquatic plant management community. This fourth edition has been specifically designed with water resource managers, water management associations, homeowners and customers and operators of aquatic plant management companies and districts in mind. Our goal in preparing this handbook is to provide basic, scientifically sound information to assist decision-makers with their water management questions.

Life originated and evolved in water. Later the The tropical countries where the need to under plants moved out of water, conquered the land and stand the natural ecosystems is far greater because became dominant over it. The evolution through they are under intensive pressure from develop the millennia resulted in enormous complexity of ment from a rapidly growing human population, form, tissue organisation, reproductive mechan have generally devoted much less attention to the isms and specialisation of taxa in different niches. studies of aquatic ecosystems. The Indian subconti At some stage during evolution, some plants devel nent is a well-recognised biogeographic region with oped appropriate morphological and physiological a distinct geological history, climate, soils and adaptations and reverted back to the aquatic and/ biota. It is also distinct in the history of human civilisation and cultures which have a profound bear or semi-aquatic habitat. These plants, perhaps with the exception of a few ing on the natural ecosystems. This book is in with beautiful flowers, have attracted little atten tended to provide the state of our knowledge of the tion from mankind. The fact that humans evolved aquatic and semi-aquatic vegetation in the inland in a tropical forest or savanna environment appears freshwaters of the subcontinent. The book covers responsible for a permanent bias in human atti only the herbaceous vegetation, since there is al tudes towards land and its biota.

Interest in the biology of African 'wetlands' was initiated in the last century with the hypothesis that Lake Tanganyika was once part of a Jurassic sea, and was furthered by Cunnington's expedition at the beginning of this century which proved that it was not. In the late 1920's, ecological studies, encouraged by the growing importance of inland fisheries, were started hy British, French and Belgian biologists. Some twenty years later several government limnological research centres and fishery departments were established in tropical Africa, and scientific progress was accelerated. Scientific collaboration between the regions south of the Sahara was started formally in 1951 by the Scientific Council for Africa and stimulated by the International Biological Programme (1964-74) with its emphasis on biological productivity. Some of its interests were takcn on by SCOPE which recently selected continental wetlands as a Special Project; hence this book. The five authors, with-Patrick Denny as editor, have made a very valuable contribution both to science and to thc management of Africa's natural rcsourccs: thcy have filled a gap in the synthesis of knowledge about Africa's environments which is long overdue. The term 'wetland' is used today in several different contexts. For this purpose, it excludes the seas and large open inland waters. which are too deep for rooted plants, but includes the huge areas of floodplains and dambos which may change seasonally from standing water to very dry lands.

Disturbance ecology continues to be an active area of research, having undergone advances in many areas in recent years. One emerging direction is the increased coupling of physical and ecological processes, in which disturbances are increasingly traced back to mechanisms that cause the disturbances themselves, such as earth surface processes, mesoscale, and larger meteorological processes, and the ecological effects of interest are increasingly physiological. Plant Disturbance Ecology, 2nd Edition encourages movement away from the informal, conceptual approach traditionally used in defining natural disturbances and clearly presents how scientists can use a multitude of approaches in plant disturbance ecology. This edition includes nine revised chapters from the first edition, as well new, more comprehensive chapters on fire disturbance and beaver disturbance. Edited by leading experts in the field, Plant Disturbance Ecology, 2nd Edition is an essential resource for scientists interested in understanding plant disturbance and ecological processes. - Advances understanding of natural disturbances by combining geophysical and ecological processes - Provides a framework for collaboration between geophysical scientists and ecologists studying natural disturbances - Includes fully updated research with 5 new chapters and revision of 11 chapters from the first edition