The Boreal Ecosystem

The Boreal Ecosystem presents an overview of the state of knowledge on the boreal forest region of North America, with extensive reference to the boreal regions of Europe and Asia.
Initial sections of this book deal with aspects of the floristic composition and evolutionary history of the boreal vegetation. These introduce subsequent discussions on the processes at work in vegetation, soils, and the atmosphere—in short, with the boreal forest as an ecosystem, the sum total of the influences of many closely interlaced biotic and physical factors. These include not only plant species that make up the visible vegetation but also nutrients, soil, temperature, rainfall, progression of the seasons, soil microflora, arthropods, insects, and larger animals such as marten, otter, beaver, moose, caribou, bear, and wolf, and man. All are closely linked strands in the web of life, a web apart from, yet dependent on and influencing, the raw physical environment. This book should serve as an introduction and reference source to its audience: undergraduate and graduate students in the biological and ecological disciplines, research workers in these fields as well as in related areas such as soil science, agronomy, genetics, and climatology; in short, everyone with an interest in boreal ecology.

Preface

A Note on Nomenclature

1. Introduction: Boreal Ecology and Ecosystems Analysis

North American and Eurasian Similarities

Boreal Ecosystematics

Community Structure: Continuum Theory

Investigating Native Communities

The Basic Elements

Problems of Modeling

Summary

References

2. History of the Boreal Vegetation

Species and Environment

Dispersal

Origins of the Flora

The End of the Tertiary

Survival in Refugia

Postglacial Vegetation

The Palynological Record

Postglacial History

The Southern Boreal Border

The Northern Border

Forest-Tundra Communities

Ecological Significance of Historical Events

References

3. Climate of the Boreal Forest

Boreal Climate: General Discussion

Climatic Parameters

Local Boreal Climates

Forest Systems Climatology

Atmospheric Subsystem

Radiation and Temperature

Local Energy Budget

Climate and Permafrost

Climate and Species Distribution

References

4. The Boreal Soils Subsystem

Genesis of Podzol Soils

The Chemical Processes

The Geography of Podzols

Soil Classification: Boreal Regions

Genetic Variations and Plant Communities

Moisture and Permafrost

Soil Organisms

Soil Microorganisms

Soil Animals

Summary: Climate and Soils

References

5. Boreal Communities and Ecosystems: The Broad View

Plants and Environment

The Circumpolar Boreal Forest

The North American Boreal Continuum

Alaska

The Cordillera

Northwestern Mackenzie-Yukon Region

Southwestern Mackenzie and Northern Alberta

The Canadian Shield Region

Shield Communities; Species Composition

Boreal Forests of Eastern Canada

Gaspé-Maritime Region

The Forests of Balsam Fir

Cape Breton and Newfoundland

Labrador-Ungava

Northern Central Quebec

Black Spruce Communities

Altitudinal Tree Line

The Northern Forest Border

Lichens and Mosses of the Forest Floor

Mosses in the Communities

The Appalachian Extension

Extent of the Eurasian Boreal Forest

Summary

References

6. Relationships of Canadian Boreal Plant Communities

Procedure

Statistical Methods

Results

Discussion

Broad Climatic Relationships

The Study

Species Behavior

Regional Environmental Analysis

Future Possibilities

Summary

References

7. Boreal Communities and Ecosystems: Local Variation

Environmental Gradients

Environmental Gradients: Moisture

Environmental Gradients: Light and Shade

Environmental Gradients: Nutrients

The Dynamics of Competition: Adaptation

Succession

Neoclassic Succession Concepts

Permafrost and Succession

Succession in Peatlands

The Ecology of Fire

Sapling Establishment

Conclusion

References

8. Nutrient Cycling and Productivity

Nutrient Cycling and the Boreal Ecosystem

The Nature of Cycling Processes

Chemical Changes during Decomposition

Nutrient Cycles Through Soil Populations

The Carbon Cycle

The Nitrogen Cycle

The Nitrogen Cycle in Forest Stands

Other Elements

Effects of Fire on Cycling

Productivity: Community Comparisons

The Lichen Associates of the Communities

Ecosystem Nutrients and Management

References

9. The Trophic Pyramid: Animal Populations

Plants and Animals

Wildlife: A Biotic Factor

Biomass of the Avifauna

The Trophic Levels

The Plant-Moose-Wolf Subsystem

The Wolverine and Wolf Compared

Role of Insects

Effects of Fire on Animal Populations

Population Cycles

References

10. Boreal Ecology and the Forest Economy

Regional Variations

Succession

The Forest Border

Soils and Podzolization

Community Structure

The Forest Economy: Resources

Managing the Forest Ecosystem

Exploitation and Management

The Bioregenerative System

Management in Northern Regions

Wildlife Management

Production and Management

Forest Management

The Outlook for the Future

References

11. Epilogue

Text

References

Appendix I Analysis of Boreal Soils

Appendix II Broad Geographical Species Relationships

Appendix III Community Composition

Appendix IV Frequency of Occurrence of Lichens

Appendix V Species Frequently in Black Spruce Communities

Appendix VI Species in Boreal Forest Literature

Appendix VII Special Definitions

Subject Index

Species Index