MANAGING FORESTS FOR BIODIVERSITY

Abstract

Hunter, M.L. , ed. ( 1999 ) Maintaining biodiversity in forest ecosystems. . Cambridge University Press , Cambridge, UK . xiv + 698 pp, figs, tables, photos, index. Paperback: Price £27.95 , ISBN 0 521 63768 6 . Hardback: Price £65.00, ISBN 0 521 63104 1. The request to review this book ended with the comment ‘I hope that you enjoy reading this book’— I did. Professor Hunter sets out to ‘reach a broad audience with the latest thinking about maintaining forest biodiversity’ with a particular focus on students and those managing forests on a day-to-day basis. On the whole I think he and the authors of the 33 chapters have succeeded. I can see this becoming a standard reference book for forestry and resource management/ecology courses. For the practitioner it will be a book to dip into when he/she wants to explore the scientific background to current recommendations on the best strategies for forest biodiversity management. The book is in four main sections. The introductory chapters covering definitions of biodiversity and principles of ecological forestry. A second section looks at forest biodiversity at the landscape scale. This is followed by chapters dealing with diversity at the stand scale, including for example the treatment of dead wood, the significance of woodland structure, and the identification and management of keystone or feature species. The final section is a little more disparate but brings in policy, social and economic issues. The chapters are not light reading, but they are full of information. The arguments are well-made and the limits to our understanding of the issues, and contradictions and ambiguities in research findings, are identified. The text is broken up well by tables, figures, line drawings, and boxed sections, although I feel that the few black and white photographs do not add much to the text. There are short case studies in most chapters — some of these work well, in others I felt that more detail was needed for the points that were being made to be understandable. Each chapter also includes a brief summary, suggestions for further reading (important if the book is to be used by students) and an extensive reference list. A very valuable aspect of this book is its breadth. The emphasis is on managing for biodiversity in natural/seminatural forests but there is also discussion of artificial plantations and restoration of forest on degraded land. It is about forests, but not just about the dynamics of the trees: other groups of plants and animals (and genetic conservation principles) are considered. Abiotic factors such as fire, altitude and possible climate change, and human factors, not least socio-economic ones, are brought in. While these last are not covered in as much detail as some other issues, they are dealt with sufficiently for the reader to appreciate their significance and follow up ideas as appropriate. The authors and much of the material shows a strong North American bias which is recognised in the Preface. More could have been made of European and southern temperate research although possibly this would have made it more difficult to maintain the strong coherence that there is both within and between chapters. Notwithstanding this bias however the emphasis on principles and approaches to biodiversity management will be widely applicable throughout the north temperate and boreal zones and to a lesser extent for those working in the southern temperate zone. While useful comparisons are made with tropical forest in some chapters there is not the space or in some cases knowledge to do them justice. Two areas I felt were lacking. The first is a major consideration of the effects of herbivores, both large ungulates (deer, cattle, etc.) and insect defoliators, on forest structures at both standard landscape levels. Grazing, browsing and the impact of deer receive only passing references: there are for example just three entries in the index for insect outbreaks, all minor. Secondly methods for classifying and mapping woodland variation particularly at a landscape scale are only touched upon in a number of places. It would have been useful to have a section specifically on this topic perhaps linked to the chapter on forest reserves. Finally one thing that this book reflects well are the shifting paradigms within forestry in both Europe and North America. Whereas the primary focus in the past was on timber production, the emphasis now is much more on management to meet multiple objectives and in ways that more closely reflect natural processes and patterns. Given its size and coverage, and notwithstanding the minor criticisms noted above, it is very good value for money.