Natural Disturbances And Historic Range Of Variation

This book discusses the historic range of variation (HRV) in the types, frequencies, severities and scales of natural disturbances, and explores how they create heterogeneous structure within upland hardwood forests of the Central Hardwood Region (CHR). The book was written in response to a 2012 forest planning rule which requires that national forests to be managed to sustain ‘ecological integrity’ and within the ‘natural range of variation’ of natural disturbances and vegetation structure. Synthesizing information on HRV of natural disturbance types, and their impacts on forest structure, has been identified as a top need.

What is a natural forest disturbance? How well do we understand natural forest disturbances and how might we emulate them in forest management? What role does emulation play in forest management? Representing a range of geographic perspectives from across Canada and the United States, this book looks at the escalating public debate on the viability of natural disturbance emulation for sustaining forest landscapes from the perspective of policymakers, forestry professionals, academics, and conservationists. This book provides a scientific foundation for justifying the use of and a solid framework for examining the ambiguities inherent in emulating natural forest landscape disturbance. It acknowledges the divergent expectations that practitioners face and offers a balanced view of the promises and challenges associated with applying this emerging forest management paradigm. The first section examines foundational concepts, addressing questions of what emulation involves and what ecological reasoning substantiates it. These include a broad overview, a detailed review of emerging forest management paradigms and their global context, and an examination of the ecological premise for emulating natural disturbance. This section also explores the current understanding of natural disturbance regimes, including the two most prevalent in North America: fire and insects. The second section uses case studies from a wide geographical range to address the characterization of natural disturbances and the development of applied templates for their emulation through forest management. The emphasis on fire regimes in this section reflects the greater focus that has traditionally been placed on understanding and managing fire, compared with other forms of disturbance, and utilizes several viewpoints to address the lessons learned from historical disturbance patterns. Reflecting on current thinking in the field, immediate challenges, and potential directions, the final section moves deeper into the issues of practical applications by exploring the expectations for and feasibility of emulating natural disturbance through forest management.

This comprehensive collection of provocative papers provides a scientific foundation for justifying the use of and a solid framework for examining the ambiguities inherent in emulating natural forest landscape disturbance. Contributors range from policymakers and forestry professionals to academics and conservationists, offering a balanced view of the promises and challenges of the forest management paradigm in sustaining forest landscapes. The book opens with an overview of foundational concepts, a detailed discussion of emerging forest management paradigms and their global context, and an examination of the ecological premise for emulating natural disturbance. This section also explores the current understanding of natural disturbance regimes, including the two most prevalent in North America: fire and insects. The volume then uses several geographically diverse case studies to address the characterization of natural disturbances and the development of applied templates for their emulation through forest management. The emphasis on fire regimes reflects the greater focus that has traditionally been placed on understanding and managing fire, compared with other forms of disturbance, and utilizes several viewpoints to address the lessons learned from historical disturbance patterns. Reflecting current developments in the field, immediate challenges, and potential directions, this collection concludes with a penetrating look at practical applications, exploring the expectations for and feasibility of emulating natural disturbance through forest management.

Ecologists are aware of the importance of natural dynamics in ecosystems. Historically, the focus has been on the development in succession of equilibrium communities, which has generated an understanding of the composition and functioning of ecosystems. Recently, many have focused on the processes of disturbances and the evolutionary significance of such events. This shifted emphasis has inspired studies in diverse systems. The phrase "patch dynamics" (Thompson, 1978) describes their common focus. The Ecology of Natural Disturbance and Patch Dynamics brings together the findings and ideas of those studying varied systems, presenting a synthesis of diverse individual contributions.

This edited volume presents original scientific research and knowledge synthesis covering the past, present, and potential future fire ecology of major US forest types, with implications for forest management in a changing climate. The editors and authors highlight broad patterns among ecoregions and forest types, as well as detailed information for individual ecoregions, for fire frequencies and severities, fire effects on tree mortality and regeneration, and levels of fire-dependency by plant and animal communities. The foreword addresses emerging ecological and fire management challenges for forests, in relation to sustainable development goals as highlighted in recent government reports. An introductory chapter highlights patterns of variation in frequencies, severities, scales, and spatial patterns of fire across ecoregions and among forested ecosystems across the US in relation to climate, fuels, topography and soils, ignition sources (lightning or anthropogenic), and vegetation. Separate chapters by respected experts delve into the fire ecology of major forest types within US ecoregions, with a focus on the level of plant and animal fire-dependency, and the role of fire in maintaining forest composition and structure. The regional chapters also include discussion of historic natural (lightning-ignited) and anthropogenic (Native American; settlers) fire regimes, current fire regimes as influenced by recent decades of fire suppression and land use history, and fire management in relation to ecosystem integrity and restoration, wildfire threat, and climate change. The summary chapter combines the major points of each chapter, in a synthesis of US-wide fire ecology and forest management into the future. This book provides current, organized, readily accessible information for the conservation community, land managers, scientists, students and educators, and others interested in how fire behavior and effects on structure and composition differ among ecoregions and forest types, and what that means for forest management today and in the future.