Book Reviews: Conservation Biology

In the first five years of the 1990's decade, the National Institute for Scientific Research for Cooperative Development (English for the French Scientific Research Institute: ORSTOM) and the Brazilian scientific institute INPA (Instituto Nacional de Pesquisas da Amazonia) lead interdisciplinary research on extractivism in Central Amazonia. This work, undertaken by a team of Franco-Brazilian scientists, was financed by the UNESCO, the French Ministry to the Environment and the Commission to European Communities. The results of a variety of scientific investigations are presented in the reviewed book in an original format. The short articles outlining the results of a particular research topics are grouped in four major chapters. These major subdivisions outline such broad topics ranging from the history of extractivism in Amazonia to the ecological and socioeconomic perspectives of this activity in the basin. These articles were written by a variety of experts. What makes this book challenging, though profoundly interesting to read, is the diverse background of the scientists. Economists, sociologists, botanists, geographers, agronomists and anthropologists all contribute to the synthesis by authoring an article. These case studies are therefore very diverse in scope. For example, Arnaldo Carneiro Filho (geographer) describes the history of the town of Manaus. Aline de Castro (botanist) compares the natural harvesting to the agro-forestry management of Açai; (Euterpe precatoria). Some of the ecosystemic studies would have benefit of enhanced cartographic analysis using GIS based data. The maps included in the texts lack geographic names for townships and main river course. Furthermore, the reader would have acquired a better understanding of the forces at work in the extractivist exploitation of the Amazon basin by an examination of landscape ecology issues. Modeling at the landscape level of the various alternatives to the traditional activity of extractivism is missing. A beneficially surprising conclusion, which ties the eclectic body of work comes at the end of the book and is authored by Jean-Paul Lescure (botanist, coordinator of the multidisciplinary study). Last, we are presented with the advantages and the drawbacks of extractivist activities in Amazonia. In a nutshell, extractivism does not generate superior revenues compared to agricultural activities such as Manioc monoculture. Extractivism may have a negative impact on biodiversity, depending on the botanical species harvested and the intensity of exploitation. The limiting factors to extractivist activities are essentially socioeconomic in scope. Furthermore, the beneficial aspects of Amazonian extractivism lie in its inherent flexibility and its capacity to integrate in complex production systems.

There is a conscious effort to thoroughness made by the editors. The book comes with a Portuguese and English summary. Glossaries of Portuguese terms (both botanical and vernacular), acronyms, were placed at the end of the book. Each case study comes with a complete bibliography specific to the research presented. Finally, for the botanically minded a Linnean index of botanical taxa is included. These texts form a solid body of work which is difficult to synthesize. The reader is left with the task of forming independently an educated point of view on the issue of forest extractivism in Amazonia. This type of organization is quite common in interdisciplinary works, though a synthesis at the end of each major chapter could have helped here. - Laurent M. Meillier, University of California, Davis, Clear Lake Environmental Research Center, Lakeport, CA.

Tropical Forest Remnants: Ecology, Management, and Conservation of Fragmented Communities Laurance, William F. and Bierregaard, Richard O., Jr., editors. 1997 ISBN 0-226-46899-2 (paper US$38) 226-46898-4 (cloth US$105) 632 pp. University of Chicago Press, 5801 South Ellis Ave., Chicago IL 60637 - The effects of forest fragmentation on biodiversity and ecosystem properties are the topics of this important new book. I had the opportunity to read this book shortly after attending a conference where one of the symposia was on tropical forest restoration: many of the speakers worked in areas where forests persisted only as small fragments. Clearly, a need existed to bring together in a single book many of the widespread studies on forest fragmentation to enhance the dissemination of ideas useful in research and management.

Laurance and Bierregaard assembled a well-rounded group of articles (33) from scientists working in Central America, the Caribbean, South America, Madagascar, Indian Ocean, Southeast Asia, New Guinea, and Australia. Curiously, tropical Africa is absent. They divided the book into sections (Economics, Physical Processes, Faunas, Plants, Restoration, Reserve Design, and Summary). Each section is introduced by an overview by Laurance that summarizes the contributions of each chapter. Length of the sections varies, with the section on faunas contributing the bulk of the book (11 chapters, 190 pages). This dominance reflects the many studies on faunal assemblages (butterflies, birds, frogs, mammals, and even centipedes) in tropical forest fragments. Befitting an edited volume, there are a wide range of topics in the other sections. Chapters range from economic forces explaining deforestation, the use of GIS and landscape ecology in quantifying fragmentation, to studies of the microclimate of forest fragments.

The section on plants and plant-animal interactions only comprises 72 pages and 5 chapters. However, plants and forests are mentioned throughout the book. In the plant section, Nason, Aldrich, and Hamrick present an excellent chapter on gene flow and genetic structure in tropical tree populations. One of their conclusions is that effects of forest fragmentation on gene flow depend on the population structure of a species. If tropical trees persist as metapopulations, isolated remnant trees may play important roles in gene flow and genetic structure if animal pollen and fruit vectors are not limiting. Other chapters in the plant section include a model of predicting rates of plant extinction based on a distribution profile of neotropical plant species, a study of seed predation of large-seeded tree species in forest fragments in Australia, and a study of recolonization of lava flows by native and exotic species in forest fragments on La Réunion Island in the Indian Ocean.

One of the more interesting conclusions of the book is that forest fragmentation has less of an impact on plant biodiversity than on animal biodiversity. Many species and populations of long-lived tropical plants persist in tropical forest fragments (Corlett and Turner - Chapter 22, ìLong-term survival in tropical forest remnants in Singapore and Hong Kongî). However, faunal assemblages of pollinators, frugivores and seed predators have been altered or eliminated in many forest fragments, potentially leading to population declines. Thus, the future of plant populations in forest fragments may be at risk, especially for species with specialized pollinators or seed dispersers.

One of the chapters in the restoration section (Lamb et al. - Chapter 24, ìRejoining habitat remnants: restoring degraded rain forest landsî) suggests restoring tropical forests through some type of plantation forestry. Although this approach may be useful for restoring ecosystem properties and for rehabilitating degraded soils, plantation forestry is not likely to meet the ecological requirements of many tropical species. A likely solution may lie in some combination of naturally regenerated forest, intensively managed natural forest, and tropical plantation forestry, depending on local needs and land use history.