MAPPING UNDISTURBED LANDSCAPES in ALASKA Overview Report
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WRI REPORT 10 G Street, NE Suite 800 Washington, DC 20002 www.wri.org JAMES STRITTHOLT RUTH NOGUERÓN JOHN BERGQUIST Conservation Biology Institute MILA ALVAREZ 260 SW Madison Ave., Suite 106 Corvallis, OR 97333 www.consbio.org MAPPING UNDISTURBED LANDSCAPES IN ALASKA Overview Report MAPPING UNDISTURBED LANDSCAPES IN ALASKA AN OVERVIEW REPORT JAMES R. STRITTHOLT RUTH NOGUERÓN JOHN BERGQUIST MILA ÁLVAREZ September 2006 F O R E S T L W A A B T C O H L G WASHINGTON, DC WRI: MAPPING UNDISTURBED LANDSCAPES IN ALASKA i KAREN HOLMES EDITOR HYACINTH BILLINGS PUBLICATIONS DIRECTOR MAGGIE POWELL LAYOUT Each World Resources Institute report represents a timely, scholarly treatment of responds to the guidance of advisory panels and expert reviewers. Unless otherwise a subject of public concern. WRI takes responsibility for choosing the study topic stated, however, all the interpretation and fi ndings set forth in WRI publications are and guaranteeing its authors and researchers freedom of inquiry. It also solicits and those of the authors. © 2006 World Resources Institute © 2006 Conservation Biology Institute All rights reserved. ISBN: 1-56973-622-7 Cover Photographs: Alaska Highway © iStockphoto.com/ra-photo; Brown Bear © iStockphoto.com/Vera Bogaerts; Mountain Glacier Lake © iStockphoto.com/Sunday Riley; Glacier © iStockphoto.com/Marketa Ebert Background satellite picture: US Geological Survey. Landsat 7 ETM + Satellite Sensor. 1999 WRI: MAPPING UNDISTURBED LANDSCAPES IN ALASKA ii CONTENTS Acknowledgments ........................................................................................v Acronyms ......................................................................................................vi Executive Summary ......................................................................................1 1. Introduction ..............................................................................................7 2. Mapping Approach and Criteria ..............................................................10 2.1 Criteria for Determination of “Intactness” ...........................................10 2.2 Defi nition of Intact Forest Landscapes (IFLs) .....................................11 2.3 Defi nition of Forest Landscape Fragments (FLFs) and Why These Tracts Are Important .........................................................12 3. Methods .....................................................................................................13 3.1 Delineation of the Study Area .............................................................13 3.2 Mapping Intact Forest Landscapes and Forest Landscape Fragments ................................................................14 3.3 Additional Analyses .............................................................................16 3.4 Limitations of the Analysis ..................................................................17 4. Results .......................................................................................................20 5. Conclusions and Next Steps ....................................................................28 Map Section ...................................................................................................31 References .....................................................................................................45 Appendix 1: Detailed Method .......................................................................47 Appendix 2: Ecological Characteristics of Alaska’s Boreal Zones and Coastal Temperate Forests ...............................................51 Appendix 3: Review Process .........................................................................59 Appendix 4: Statistical Data .........................................................................62 WRI: MAPPING UNDISTURBED LANDSCAPES IN ALASKA iii TABLES, FIGURES, AND MAPS Figures Tables 1. Classifi cation and Size Thresholds for Blocks of Un- 1. Buffering of Human Infrastructure Features in Map- disturbed Forest Landscapes in Alaska’s Boreal and ping Alaska’s Boreal Forests, Compared with Buffer- Coastal Temperate Forests (thousands of ha) ing Used in Canada and Russia Mapping Studies 2. Comparison of Techniques for Eliminating Areas with 2. Overview of Land Ownership in Study Area and State- Evidence of Human Disturbance Using GIS Data Layers wide Alaska 3. Two-Step Process for Detecting Areas of Human Dis- turbance in Alaska’s Forest Landscapes Maps 1 4 . Study Area and Distribution of Satellite Imagery Used . Share of Alaska’s Land Area in Intact Forest Land- in This Analysis scapes, Undisturbed Islands, and Forest Landscape Fragments, by Forest Zone 2. Ecological Zones Defi ned in the Study Area 5. Land Ownership in Alaska by Agency (millions of ha 3. Ownership Map owned) and Share of Land in Intact Forest Landscapes, 4. Protected Areas in Alaska Undisturbed Islands, and Forest Landscape Fragments 5 6 . Data Sources for the Analysis of Forest Composition . Share of Land Ownership in Intact Forest Landscapes, in Boreal Forests Undisturbed Islands, and Forest Landscape Fragments in Alaska’s Boreal and Coastal Regions, by Agency 6. Intact Forest Landscapes and Forest Landscape Frag- ments in the Boreal Region 7. Share of Intact Forest Landscapes, Undisturbed Is- lands and Forest Landscape Fragments with Protected 7. Intact Forest Landscapes, Undisturbed Areas, and For- Status, by Forest Zone est Landscape Fragments in the Kenai-Yakutat Zone 8. Share of Intact Forest Landscapes, Undisturbed Is- 8. Intact Forest Landscapes, Undisturbed Islands, and lands, and Forest Landscape Fragments with Protected Forest Landscape Fragments in the Tongass Zone Status, by Size Class 9. Intact Forest Landscapes, Undisturbed Islands, and 9. Share of Intact Forest Landscapes and Undisturbed Forest Landscape Fragments in the Kenai-Yakutat Islands with Protected Status Versus Share in Inven- Zone toried Roadless Areas, by Forest Zone in Alaska’s 10. Intact Forest Landscapes, Undisturbed Islands, Forest Coastal Region Landscape Fragments, Protected Areas and Invento- 10. Share of Intact Forest Landscapes, Undisturbed Is- ried Roadless Areas in the Tongass Zone lands, and Forest Landscape Fragments with Protected 11. Forests and Non-Forest Vegetation in Intact Forest Status Versus Share in Inventoried Roadless Areas, by Landscapes and Forest Landscape Fragments in the Size Class Boreal Region 11 . Distribution of Forest Canopy Cover in Intact For- 12. Forests and Non-Forest Vegetation in Intact Forest est Landscapes and Forest Landscape Fragments in Landscapes, Undisturbed Islands, and Forest Land- Alaska’s Boreal Region, by Size Class and Forest Zone scape Fragments in the Kenai-Yakutat Zone 12 . Distribution of Land Cover Types in Intact Forest 13. Forests and Non-Forest Vegetation in Intact Forest Landscapes, Undisturbed Islands, and Forest Land- Landscapes, Undisturbed Islands, and Forest Land- scape Fragments in Kenai-Yakutat Zone scape Fragments in the Tongass Zone 13 . Distribution of Land Cover Types in Intact Forest 14. Fire Disturbances in Boreal Intact Forest Landscapes Landscapes, Undisturbed Islands, and Forest Land- and Forest Landscape Fragments scape Fragments in Tongass Zone 14. Area and Frequency of Forest Fires in Alaska’s Boreal Region, 1990–2005 WRI: MAPPING UNDISTURBED LANDSCAPES IN ALASKA iv ACKNOWLEDGMENTS his report would not have been possible without Stephen Adam for their critical support in the last phases the data, information, and technical and scientifi c of the project. Former WRI staff Dirk Bryant, Jill Hartsig, Tadvice from many colleagues. David Albert, Frank Ralph Ridder, Kumiko Shimamoto, and Jenny Frankel- Ahern, Eugene Degayner, Page Else, Gary Fischer, Shane Reed also supported the project securing funding, manag- Feirer, Rod Flynn, Jason Geck, Mike Heiner, Eric Ka- ing, and conducting research and fact-checking for this sischke, Winifred B. Kessler, Matt Kirchhoff, Jerry Minick, report. Tyson Walker conducted a portion of the analysis John Payne, Will Putman, John Schoen, Kenneth Winter- and mapping. Within CBI, we acknowledge the advice, berger, Evie Witten, Abby Wyer, and Ma Zhenkui provided help, and support of Kim Bredensteiner, Pamela Frost, useful comments, data, information, and guidance that Gerald Heilman, Nick Slosser, and Nancy Staus. The skill- substantially improved our work. ful editing of Karen Holmes substantially improved our effectiveness communicating the many complexities of We benefi ted greatly from experiences from colleagues this work. mapping intactness in Russia and Canada. Thanks to Dmitry Aksenov, Alexey Yaroshenko, and Peter Potapov, We are grateful for the support of the Surdna Founda- and thanks to Peter Lee and Aran O’Carroll for all their tion, the WestWind Foundation, the Charles Stewart Mott support and guidance. Foundation, Norm Thompson Inc., and the Bank of Amer- ica. Their fi nancial support was integral to the develop- Thanks also to our colleagues at WRI and CBI who were ment of this project. All Geographic Information Systems generous with their time, input and support through- (GIS) and remote sensing analyses were completed using out the project. At WRI, David Jhirad, Brad Kinder, Lars software donated by Environmental Systems Research In- Laestadius, Susan Minnemeyer, and Janet Ranganathan stitute Inc. (ESRI) and Leica Geosystems (ERDAS). provided invaluable comments to early versions of the report. Gayle Coolidge and Jennie Hommel shepherded The Landsat satellite images used in this work were ob- the manuscript