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Forest Dynamics and Disturbance Regimes: Studies from Temperate Evergreen—Deciduous Forests
Forest Ecology and Management 172 (2003) 125±126
Book review Forest Dynamics and Disturbance Regimes: Studies from Temperate EvergreenÐDeciduous Forests L.E. Frelich, Cambridge University Press, Cambridge, 2002, 266 pp., ISBN 0521650828 In recent decades, the resurgence of disturbance as a critical consideration in ecology has led to a large body of research on forest disturbance ecology. Lee Frelich and his mentors, particularly C.G. Lorimer, have made strong contributions in the area of forest community response to disturbance at the level of stands and landscapes. Findings from two decades of research concentrating on forests in the Great Lakes area of the northcentral United States are summarized in this clear and reasonably concise book. A quick browse through the references reveals a list of international authors, but papers by Frelich and Lorimer are most frequently referenced. Relying heavily on studies in the Lake States Region, Frelich presents his insights and perspectives on forest dynamics, a topic that has both captivated and confounded ecologists. The book is varied in content. Quantitative approaches to the study of forest disturbance ecology are emphasized. Methods and applications for quantitative ecological research via ®eld studies and mathematical modeling are presented. The spatial context ranges from within-stand neighborhoods to landscapes. The temporal domain is primarily decades to several centuries. Forest dynamics theory is also covered. Case studies from the Lake States Region are often provided to convey and support ideas. The subject matter is suitable for advanced students and practicing scientists in plant ecology, landscape ecology and forest science. The overall objective of the book is to improve understanding and prediction of forest response to natural disturbance. Three general themes are outlined in Chapter 1. The ®rst theme is to demonstrate how the combined effects of ®re, wind and herbivory can impact forest dynamics. The second is to demonstrate
the role of species composition in these complex systems. The third is to examine how spatial scale affects apparent responses to disturbance. Forest disturbance regimes are discussed after providing the background on forests of the Lake States Region (with special attention to a few extensive forest remnants). Pertinent de®nitions, metrics and fundamental concepts are presented along with examples of actual agents of disturbance. Six types of disturbance regime are distinguished based on frequency, size, type and severity of disturbance. How stand disturbance history can be studied is the subject of Chapter 3. Several different approaches are discussed, but most of the chapter is devoted to the tree-ring methodology. The information provided on tree-ring sampling and analysis is quite detailed and extensive. Characterization of canopy gap disturbances, canopy tree residence times and canopy turnover rates also receives attention here. In Chapter 4, Frelich discusses the disturbance and dynamics of stand composition and structure. Like several other forest ecologists, he recognizes four stages of stand development after severe disturbance. He modi®es C.D. Oliver's four-stage model of stand development, primarily by renaming the latter two stages as the demographic transition stage and the multi-aged stage. They correspond to Oliver's understory reinitiation and old-growth stages. Various conceptual models of succession are presented along with ®ve case studies for various forests of the Lake States Region. The fact that forest dynamics is a potentially varied and complex subject becomes clear. Nonetheless, patterns of stand development and succession can be discerned. Idealized `guidelines for successional change' are summarized for each of the ®ve case study forest types. How disturbances affect landscape structure is introduced in Chapter 5. Methods for exploring overall, non-spatial structure of forested landscapes are presented. For example, what is the age structure of
0378-1127/02/$ ± see front matter # 2002 Elsevier Science B.V. All rights reserved.
126
Book review
stands in a particular landscape and what can we deduce from it? Pertinent models of disturbance probability and stand age are discussed. How the rotation period for disturbance can be estimated is emphasized here. How transition matrix models of vegetation growth stages can be constructed and applied is demonstrated. The issue of old-growth forest on the landscape is addressed. Nine de®nitions of old-growth forest are listed and critiqued. Like several other ecologists, Frelich concludes that stand age is the most important concern. He proceeds to demonstrate how to estimate the amount of old-growth forest on a landscape subject to a speci®ed disturbance regime. In Chapter 6, fundamental spatial processes are introduced. Disturbance size effects and neighborhood effects are discussed. A compromise in the debate over a `climax forest landscape' versus a disturbance-governed landscape is proposed for hemlock-hardwood forests. It is suggested that moderate windstorms have the highest cumulative impact on the landscape. Fire is not as frequent, but its effects can be signi®cant. Recovery on a disturbed landscape is divided into `in-place succession' and `wave-form succession'. The wave-form succession refers to a landscape pattern resulting from interspeci®c differences in dispersal into disturbance patches. In this case, disturbance size does matter. A ®nal topic is the role of neighborhood effects in patch formation. Potential neighborhood in¯uences on patch dynamics and structure are explored with a simulation model. Although it is conceded that other factors may regulate patch formation, neighborhood feedbacks are thought to combine with disturbance to produce the landscape mosaic. Chapter 7 is a concise discussion of how landscape fragmentation affects natural disturbance. Why forest fragments are susceptible to loss of native species, herbivory, and altered disturbance is explained. An explicit discussion of edge effects and connectivity is noticeably absent. Nonetheless, interesting topics include a risk analysis of elimination of old forest fragments by wind disturbance, and the disturbance± dilution effect on ®re. In both cases, small fragments are less likely to be disturbed. It follows that the disturbance regime and forest composition of small or isolated fragments are distinctive. In the closing chapter, Frelich synthesizes his ®ndings by constructing a general conceptual model of
forest dynamics and disturbance. For many forests, stability of stands and landscapes is proposed in the absence of disturbance. However, disturbances, indicated by `cumulative disturbance severity', can cause linear or non-linear changes in composition. Nonlinear responses are hypothesized for communities with positive neighborhood effects (local feedbacks). Such communities resist change and exhibit a cusp response to disturbance. The resulting `cusp-catastrophe model', based on neighborhood effects and disturbance severity, is general enough to account for several common types of forest dynamics. The book has several strengths. First, it not only recognizes that forest dynamics should be studied at multiple-spatial scales, it actually synthesizes crossscale ®ndings to improve our breadth of understanding. While the earlier chapters review concepts that are several decades old, the later chapters are likely to provide new information and insights to forest ecologists. These latter chapters cover landscape-level phenomena. The ®nal chapter is a substantial contribution to forest dynamics theory. Weaknesses of the book include a limited set of references and a lack of detail on the simulation models presented. The literature cited is selective rather than exhaustive. Several major references on natural disturbance and vegetation dynamics are omitted. For this reason, the references seem to be too selective. Readers will have to go elsewhere to ®nd some highly in¯uential papers and books on the topic at hand. Another frustration is the lack of detail on the actual formulation and implementation of the simulation models presented. Much can be learned by examining and executing simulation models. Further information in appendices or a referenced internet site would increase the impact of this work. The book's strengths certainly outweigh any weaknesses. It adds to ecological theory on forest dynamics. It is valuable reading for all ecologists interested in disturbance and vegetation dynamics. Richard T. Busing Corvallis, OR, USA E-mail address: [email protected] (R.T. Busing) Accepted 29 August 2002 PII: S 0 3 7 8 - 1 1 2 7 ( 0 2 ) 0 0 4 7 7 - 2
Book review Forest Dynamics and Disturbance Regimes: Studies from Temperate EvergreenÐDeciduous Forests L.E. Frelich, Cambridge University Press, Cambridge, 2002, 266 pp., ISBN 0521650828 In recent decades, the resurgence of disturbance as a critical consideration in ecology has led to a large body of research on forest disturbance ecology. Lee Frelich and his mentors, particularly C.G. Lorimer, have made strong contributions in the area of forest community response to disturbance at the level of stands and landscapes. Findings from two decades of research concentrating on forests in the Great Lakes area of the northcentral United States are summarized in this clear and reasonably concise book. A quick browse through the references reveals a list of international authors, but papers by Frelich and Lorimer are most frequently referenced. Relying heavily on studies in the Lake States Region, Frelich presents his insights and perspectives on forest dynamics, a topic that has both captivated and confounded ecologists. The book is varied in content. Quantitative approaches to the study of forest disturbance ecology are emphasized. Methods and applications for quantitative ecological research via ®eld studies and mathematical modeling are presented. The spatial context ranges from within-stand neighborhoods to landscapes. The temporal domain is primarily decades to several centuries. Forest dynamics theory is also covered. Case studies from the Lake States Region are often provided to convey and support ideas. The subject matter is suitable for advanced students and practicing scientists in plant ecology, landscape ecology and forest science. The overall objective of the book is to improve understanding and prediction of forest response to natural disturbance. Three general themes are outlined in Chapter 1. The ®rst theme is to demonstrate how the combined effects of ®re, wind and herbivory can impact forest dynamics. The second is to demonstrate
the role of species composition in these complex systems. The third is to examine how spatial scale affects apparent responses to disturbance. Forest disturbance regimes are discussed after providing the background on forests of the Lake States Region (with special attention to a few extensive forest remnants). Pertinent de®nitions, metrics and fundamental concepts are presented along with examples of actual agents of disturbance. Six types of disturbance regime are distinguished based on frequency, size, type and severity of disturbance. How stand disturbance history can be studied is the subject of Chapter 3. Several different approaches are discussed, but most of the chapter is devoted to the tree-ring methodology. The information provided on tree-ring sampling and analysis is quite detailed and extensive. Characterization of canopy gap disturbances, canopy tree residence times and canopy turnover rates also receives attention here. In Chapter 4, Frelich discusses the disturbance and dynamics of stand composition and structure. Like several other forest ecologists, he recognizes four stages of stand development after severe disturbance. He modi®es C.D. Oliver's four-stage model of stand development, primarily by renaming the latter two stages as the demographic transition stage and the multi-aged stage. They correspond to Oliver's understory reinitiation and old-growth stages. Various conceptual models of succession are presented along with ®ve case studies for various forests of the Lake States Region. The fact that forest dynamics is a potentially varied and complex subject becomes clear. Nonetheless, patterns of stand development and succession can be discerned. Idealized `guidelines for successional change' are summarized for each of the ®ve case study forest types. How disturbances affect landscape structure is introduced in Chapter 5. Methods for exploring overall, non-spatial structure of forested landscapes are presented. For example, what is the age structure of
0378-1127/02/$ ± see front matter # 2002 Elsevier Science B.V. All rights reserved.
126
Book review
stands in a particular landscape and what can we deduce from it? Pertinent models of disturbance probability and stand age are discussed. How the rotation period for disturbance can be estimated is emphasized here. How transition matrix models of vegetation growth stages can be constructed and applied is demonstrated. The issue of old-growth forest on the landscape is addressed. Nine de®nitions of old-growth forest are listed and critiqued. Like several other ecologists, Frelich concludes that stand age is the most important concern. He proceeds to demonstrate how to estimate the amount of old-growth forest on a landscape subject to a speci®ed disturbance regime. In Chapter 6, fundamental spatial processes are introduced. Disturbance size effects and neighborhood effects are discussed. A compromise in the debate over a `climax forest landscape' versus a disturbance-governed landscape is proposed for hemlock-hardwood forests. It is suggested that moderate windstorms have the highest cumulative impact on the landscape. Fire is not as frequent, but its effects can be signi®cant. Recovery on a disturbed landscape is divided into `in-place succession' and `wave-form succession'. The wave-form succession refers to a landscape pattern resulting from interspeci®c differences in dispersal into disturbance patches. In this case, disturbance size does matter. A ®nal topic is the role of neighborhood effects in patch formation. Potential neighborhood in¯uences on patch dynamics and structure are explored with a simulation model. Although it is conceded that other factors may regulate patch formation, neighborhood feedbacks are thought to combine with disturbance to produce the landscape mosaic. Chapter 7 is a concise discussion of how landscape fragmentation affects natural disturbance. Why forest fragments are susceptible to loss of native species, herbivory, and altered disturbance is explained. An explicit discussion of edge effects and connectivity is noticeably absent. Nonetheless, interesting topics include a risk analysis of elimination of old forest fragments by wind disturbance, and the disturbance± dilution effect on ®re. In both cases, small fragments are less likely to be disturbed. It follows that the disturbance regime and forest composition of small or isolated fragments are distinctive. In the closing chapter, Frelich synthesizes his ®ndings by constructing a general conceptual model of
forest dynamics and disturbance. For many forests, stability of stands and landscapes is proposed in the absence of disturbance. However, disturbances, indicated by `cumulative disturbance severity', can cause linear or non-linear changes in composition. Nonlinear responses are hypothesized for communities with positive neighborhood effects (local feedbacks). Such communities resist change and exhibit a cusp response to disturbance. The resulting `cusp-catastrophe model', based on neighborhood effects and disturbance severity, is general enough to account for several common types of forest dynamics. The book has several strengths. First, it not only recognizes that forest dynamics should be studied at multiple-spatial scales, it actually synthesizes crossscale ®ndings to improve our breadth of understanding. While the earlier chapters review concepts that are several decades old, the later chapters are likely to provide new information and insights to forest ecologists. These latter chapters cover landscape-level phenomena. The ®nal chapter is a substantial contribution to forest dynamics theory. Weaknesses of the book include a limited set of references and a lack of detail on the simulation models presented. The literature cited is selective rather than exhaustive. Several major references on natural disturbance and vegetation dynamics are omitted. For this reason, the references seem to be too selective. Readers will have to go elsewhere to ®nd some highly in¯uential papers and books on the topic at hand. Another frustration is the lack of detail on the actual formulation and implementation of the simulation models presented. Much can be learned by examining and executing simulation models. Further information in appendices or a referenced internet site would increase the impact of this work. The book's strengths certainly outweigh any weaknesses. It adds to ecological theory on forest dynamics. It is valuable reading for all ecologists interested in disturbance and vegetation dynamics. Richard T. Busing Corvallis, OR, USA E-mail address: [email protected] (R.T. Busing) Accepted 29 August 2002 PII: S 0 3 7 8 - 1 1 2 7 ( 0 2 ) 0 0 4 7 7 - 2