Section 3 Modeling Historic Variation and Its Application for Understanding Future Variability Robert E. l(eane USDA Forest Service, Rocky Mountain Research Station, Missoula Fire Sciences Laboratory, MT, USA lthough some may doubt its usefulness in a future with rapidly changing climates, exotic introductions, and increased human land use, the historical range of variation (HRV) of ecological landscape characteristics provides a relatively useful reference point for evaluating the impacts of landmanagement activities. Unfortunately, comprehensive spatial and temporal data describing historical landscape conditions are rare for many areas, with most information being limited in geographic scope and A relatively recent. The main problem facing many ecologists, scientists, and land managers is how to quantify the HRV of landscapes in a format that is scientifically credible, useful to land management, temporally deep, and spatially extensive, while still being relevant in today's changing world. The best method for quantifying historical landscape conditions relies on a chronosequence or a series of maps or data layers from one landscape over many past time periods. However, temporally deep, spatially explicit Historical Environmental Variation in Comervation and Natu ral Resource Management, First Edition. Ed ited by john A. Wiens , Gregory D. Hayward, Hugh D. Safford, and Catherine M. Giffen. © 2012 John Wiley & Sons. Ltd. Published 2012 by John Wiley & Sons, Ltd. 111 112 Modeling historic variation and its application empirical chronosequences of landscape conditions are rare because aerial photography and satellite imagery were nonexistent before 1930, and paper maps of forest vegetation are scarce and inconsistent prior to 1900. Another method involves using digital maps from similar landscapes. taken from one or multiple time periods, and gathered across a geographic region to quantify the landscape HRV (Hessburg et aL 1999; 2000). This substitution of space for time assumes that all landscapes used to define HRV are similar in terms of environmental. disturbance. topography, and biological conditions. However. most landscapes are unique in terms of the biophysical environment and the manifestation of disturbance dynamics over time creates distinctive variations in landscape HRV characteristics because of differences in topography, orientation, wind direction. and many other microclimate, biotic. and edaphic characteristics (Keane et aL 2006). In many situations. simulation modeling provides the only viable source for generating comprehensive HRV data. This third method involves simulating historical dynamics using landscape models to produce a chronosequence of simulated spatial data to use as reference. This approach assumes that succession and disturbance processes are simulated accurately in space and time. Many spatially explicit ecosystem simulation models are available for quantifying HRV patch dynamics (see Mladenoff & Baker 1999 ; Keane eta!. 2004), but many are computationally intensive, difficult to parameterize and initialize, and complex in design, making them difficult to use across large regions over long time periods. Even with these limitations, simulation models often provide the only way to quantify HRV for many landscapes, and therefore, they are a critical tool for managing today's landscapes. Although spatial chronosequences are clearly preferable, simulated chronosequences provide a viable, and in some cases, the only, alternative to creating HRV data. This section describes the use of simulation modeling to develop HRV chronosequences for land management. The first chapter deals with all the background, issues, and limitations of creating simulated HRV time series. Important topics include landscape size, selecting the most desirable model, and data parameterization issues. The next chapter provides examples of how simulated HRV time series can be used in natural resource management at various scales. Collectively, these chapters may provide the information needed to start an HRV project using a landscape simulation model to generate historical time series, which can then be used as a reference to compare management treatment alternatives. REFERENCES Hessburg, P.F.. Smith. B.C. & Salter. R.B. (1999). A method for detecting ecologically significant change in forest spatial patterns. Ecological Applications, 9. 1252-1272. Hessburg, P.F.. Smith. B.G .. Salter. R.B .. Ottmar, R.D. & Alvarado, E. (2000) . Recent changes (1930's-1990's) in spatial patterns of interior northwest forests , USA. Forest Ecology and Management, 136, 53-83. Keane, R.E .. Cary, G.. Davies. I.D .. et al. (2004) . A classification of landscape fire succession models: spatially explicit models of fire and vegetation dynamic. Ecological Modelling. 256. 3-27. Keane, R.E., Holsinger, L. & Pratt. S. (2006). Simulating historical landscape dynamics using the landscape fire succession model LANDSUM version 4.0. General Technical Report RMRS-CTR-171CD. USDA Forest Service. Fort Collins, CO. USA. Mladenoff. D.J. & Baker. W.L. (1999). Spatial Modeling of Forest Landscape Cllm1ge. Cambridge University Press, Cambridge. UK. HISTORICAL ENVIRONMENTAL VARIATION IN CONSERVATION AND NATURAL RESOURCE MANAGEMENT Edited by John A. Wiens PRBO Conservation Science Petaluma, CA, USA School of Plant Biology University of Western Australia Crawley, WA, Australia Gregory D. Hayward USDA Forest Service Alaska Region, Anchorage, AK, USA USDA Forest Service Rocky Mountain Region Lakewood, CO, USA Hugh D. Safford USDA Forest Service Pacific Southwest Region Vallejo, CA, USA Department of Environmental Science and Policy University of California Davis, CA, USA Catherine M . Giffen USDA Forest Service National Office Washington, DC, USA @)WILEY-BLACKWELL A John Wiley & Sons, Ltd., Publication This edition first published 2012 © 2012 by John Wiley & Sons. Ltd. Blackwell Publishing was acquired by John Wiley & Sons in february 2007. Blackwell's publishing program has been merged with Wiley's global Scientific, Technical and Medical business to form Wiley-Blackwell. Registered office: John Wiley & Sons, Ltd, The Atrium. Southern Gate, Chichester, West Sussex. P019 8SQ, UK Editorial offices: 9600 Garsington Road. Oxford. OX4 2DQ. UK The Atrium, Southern Gate, Chichester, West Sussex, P019 8SQ. UK 111 River Street. Hoboken. NJ 07030-5774. USA For details of our global editorial offices. for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com/ wiley-blackwell. The right of the author to be identified as the author of this work has been asserted in accordance with the UK Copyright. Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means. electronic. mechanical. photocopying. recording or otherwise. except as permitted by the UK Copyright. Designs and Patents Act 1988. without the prior permission of the publisher. Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names. service marks. trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the publisher is not engaged in rendering professional services. lf professional advice or other expert assistance is required. the services of a competent professional should be sought. Librnry of Congress Cataloging-in-Publication Data Historical environmental variation in conservation and natural resource management I edited by John A. Wiens ... [et al.]. p.cm. Includes bibliographical references and index. ISBN 978-1-4443-3792-1 (cloth) -ISBN 978-1-4443-3793-8 (pbk.) 1. Landscape ecology. 2. Natural resourcesCo-management. I. Wiens, John A. QH541.15.L35H57 2012 333.7--<lc23 2012007159 A catalogue record for this book is available from the British Library. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Set in 9/11 pt PhotinaMT by Toppan Best-set Premedia Limited Printed and bound in Malaysia by Vivar Printing Sdn Bhd 1 2012 Front Cover: Great Basin bristlecone pine trees (Pinus longaeva) in the Patriarch Grove of the White Mountains, eastern California. Bristlecone pines growing in the White Mountains are the oldest known trees in the world, with individuals reaching ages upwards of 5000 years. Dry conditions in the White Mountains also result in exceptional preservation of remnant wood. By cross-dating dead wood with living trees, the tree-ring chronology for the White Mountains extends back almost 12,000 years. providing an exceptional example of a historical legacy. Photograph by Peter M. Brown, Rocky Mountain Tree-Ring Research. Cover Design By: Steve Thompson.