Ecology of Wildfire Residuals in Boreal Forests

Ajith Perera, Lisa Buse

• Publisher: Wiley-Blackwell
• Year: 2014
• Print ISBN:
  9781444336535
• eBook ISBN:
  9781118870587
• Edition: 1
• Topic: Biowissenschaften
• Subtopic: Ökologie

Large and intense wildfires are integral to the globally important boreal forest biome. While much is known about boreal wildfires, the focus on forest remnants that either escape or survive these intense fires is a recent phenomenon: academics now study ecological processes of wildfire residuals, forest policymakers use their patterns to design harvest strategies, forest managers consider their economic value, and conservationists recognize their intrinsic ecological importance. 

Ecology of Wildfire Residuals in Boreal Forests is the first book to explore ecological patterns and processes of what does not burn within boreal wildfires. Following a brief introduction to the boreal forest biome, it discusses the processes that form wildfire residuals; how they are studied, with various approaches and methods; the types, extent, and ecological functions of wildfire residuals; and their role in forest management applications, all in the context of ecological scale. 

This book is a reference for researchers and graduate students studying boreal forest ecology, as well as for policymakers and forest managers. It adopts a non-reductionist perspective that will be of interest to scientists from conservation science, forest ecology, forest management, and timber production. 

• Brings together fire behaviour, ecological scale, vegetation ecology, and conservation biology to provide a cross disciplinary, multi-scale, and an integrative discussion of forest fire residuals

• Captures the state of knowledge with a meta-analysis of research trends during the past few decades, with a comprehensive review of the literature, a compilation of key references, and a list of key topics relevant to the study of boreal wildfire residuals

• Identifies the major gaps and uncertainties in the present body of knowledge, including a critique of study techniques and reporting practices to date,  and proposes a set of terms  and definitions and a list of research questions and priorities

• Includes the authors' observations and research experience from boreal Canada, and information extracted from interactions with North American and European ecologists, forest managers, and conservationists

Chapter 1
Introduction

The boreal forest biome

1. Geographical distribution
2. Distinguishing features

Boreal wildfires

1. Major characteristics
2. Ecological significance

Goals and scope of the book

References

Wildfires and their role in influencing ecological processes and patterns in the boreal forest biome have drawn the attention of scientists for several decades. Much has been written on this topic, including texts by Wein and McLean (1983a), Johnson (1992), Goldammer and Furyaev (1996a), and Kasischke and Stocks (2000a), to address the physical processes that occur during and after wildfires, the effects of wildfires on forest ecosystems, the post-fire recovery process, and even the management of wildfires to minimize their economic impacts. Such focus on the physical process of wildfire and its ecological impacts may create a general impression that boreal wildfires destroy all components of boreal forest ecosystems. This is not true in most instances; many components of the forest vegetation, both above and below ground, remain alive. Many plants either escape or survive the fires and most vegetation, even if burned, retains some or all of its pre-burn structure.

The vegetation that is not burned, together with the biomass that is not completely incinerated, creates fine-scale heterogeneity within the areas burned by boreal wildfires. These post-fire remnants are a critical component of the local ecosystem recovery processes after wildfire, and contribute significantly to several ecological processes in the broader landscape beyond the spatial signature of a fire. Recently, boreal wildfire residuals have attracted increasing scientific, social, and even political attention, from the perspective of conservation biology, because of attempts to emulate post-fire patterns during forest harvesting and concerns about the ecological effects of harvesting the residuals. However, neither the presence of such post-fire residuals nor their ecology has been well recognized in the fire literature; most synthetic reviews of studies of boreal wildfires have focused on the fire process or the ecological effects of fire, not on what is left unburned.

In this context, our focus in this book is the patterns and ecological processes related to the residuals created by boreal wildfires, and the use of this knowledge in forest management. Here we explore what is known and, in so doing, identify the many questions that remain about the ecology of wildfire residuals in the boreal forest biome. We use the term “wildfire residuals” to signify all of the vegetation structure remaining after a fire: still living, in the process of dying, and killed by the fire.

In this first chapter, we briefly introduce two topics that are key to understanding boreal wildfire residuals, especially for those unfamiliar with this forest type: the boreal forest biome—its occurrence, distribution, and general characteristics; and boreal wildfire—its general characteristics and ecological significance. We then provide an overview of the goals, scope, and structure of the book.

The boreal forest biome

Though not as rich in biota as other terrestrial biomes, boreal forests still harbor many plant and animal species. Boreal forests are among the least populated of all forest biomes. Considerable portions remain uninhabited and natural ecological processes continue to occur largely without human interference, especially in North America and Russia (UNECE 2000). These forests have attracted wide interest from scientists, land managers, politicians, and the general public. Not only are boreal forests an important source of commodities (“natural resources”) such as timber, oil, and minerals, they are home to many communities of both native (indigenous) and immigrant populations, the latter drawn mainly by industries based in natural resource extraction.

More recently, boreal forests have become valued in relation to such global phenomena as biodiversity and climate change. These forests are thus considered important from a wide range of perspectives: ecological, for example for wildlife and plant habitat, and carbon budgets; economic, for example for forestry, agriculture, mining, and tourism; and social, including for settlement and recreation. Furthermore, boreal forests are also of political interest with respect to such issues as the rights of indigenous peoples, the debate over the conservation of biodiversity versus exploitation of natural resources, and the global role of these forests in climate change.

The boreal forest biome is one of the largest pools of organic carbon on Earth and is, therefore, a significant factor in regulating global and regional climates. Estimates indicate that the carbon stored in the boreal biome totals over 700 Pg, of which about 82 Pg is stored in above- and belowground plant biomass, about 200 Pg in soil, and about 420 Pg in peatlands. Carbon stored in the boreal biome thus accounts for over one-third of the total terrestrial global carbon pool (Apps et al. 1993). The forested portion of the boreal biome alone contains almost 300 Pg, which is equivalent to nearly 16% of the world's total (Kasischke et al. 1995).

In addition to this immense carbon pool, the boreal biome supplies many other ecosystem goods and services. It acts as a reservoir for biological and genetic diversity, purifies the air and water, and provides habitat for wildlife, including birds, mammals, insects, and microorganisms. The boreal biome also provides food and renewable raw materials for human use; it is a major source of softwood timber and provides jobs and economic stability to many rural and remote communities. For indigenous peoples, the boreal forest is a source of livelihood as well as the base for their culture and spiritual sustenance.

The boreal biome is unique in that it remains relatively unpopulated. Throughout most of the biome, there is more than 2 ha of forest per inhabitant (UNECE 2000). In addition, it is largely inaccessible: only about one-third of the world's boreal forests are within 10 km of any transportation infrastructure (FAO 2001), and this contributes to the fact that much of the forest remains relatively undisturbed by humans. In fact, the overwhelming majority of the global temperate and boreal forests that are “undisturbed by man” are located within Russia (81%) and Canada (13%) (UNECE 2000). Also, most of the boreal forest is under public ownership: in Canada and Russia, >90% of the forest is publically owned. The exception is the Nordic countries (e.g., Finland, Norway, and Sweden) where ≥60% is privately owned (UNECE 2000).

According to recent figures, the forested area within the boreal biome remains relatively stable, changing by ±0.5...

Table of contents

• Cover
• Title Page
• Copyright
• Dedication
• Acknowledgments
• About the companion website
• Chapter 1: Introduction
• Chapter 2: Formation of wildfire residuals
• Chapter 3: Types of wildfire residuals and their extent
• Chapter 4: Ecological roles of wildfire residuals
• Chapter 5: Role of wildfire residuals in forest management applications
• Chapter 6: Ecology of boreal wildfire residuals—a summary and synthesis
• Index
• Supplemental Images
• End User License Agreement