Ecological Studies, Vol. 107

Transcription

1 Ecological Studies, Vol. 107 Analysis and Synthesis Edited by O.L. Lange, Wiirzburg, FRG H.A. Mooney, Stanford, USA H. Remmert, Marburg, F~G

2 Ecological Studies Volumes published since 1989 are listed at the end of this book.

3 Jose M. Moreno Walter C. Oechel Editors The Role of Fire in Mediterranean-Type Ecosystems With 65 illustrations including 3 in color Springer-Verlag New York Berlin Heidelberg London Paris Tokyo Hong Kong Barcelona Budapest

4 Jose M. Moreno Departamento de Ecologfa Facultad de Biologia Universidad Complutense Madrid Spain Walter C. Oechel Department of Biology San Diego State University San Diego, CA USA Cover illustration. Map of documented fires occurring between 1938 and 1985 in Burton Mesa, California. Adapted from Figure 7-4, page 128. Library of Congress Cataloging-in-Publication Data The role of fire in Mediterranean-type ecosystems / [edited by] Jose M. Moreno, Walter C. Oechel. p. cm. - (Ecological studies; v. 107) Includes bibliographical references and index. ISBN -13: Fire ecology. 2. Mediterranean climate. 3. Plants, Effect of fires on. I. Moreno, Jose Manuel. II. Oechel, W. C. III. Series. QH545.F5R ' dc Printed on acid-free paper Springer-Verlag New York Inc. Copyright is not claimed for works by U.S. Government employees. All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer-Verlag New York, Inc., 175 Fifth Avenue, New York, NY 10010, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use of general descriptive names, trade names, trademarks, etc., in this publication, even if the former are not especially identified, is not to be taken as a sign that such names, as understood by the Trade Marks and Merchandise Marks Act, may accordingly be used freely by anyone. Production coordinated by Chernow Editorial Services, Inc., and managed by Ellen Seham; manufacturing supervised by Genieve Shaw. Typeset by Best-set Typesetter Ltd., Hong Kong ISBN -13 : e-isbn -13 : DOl: /

5 Preface During the last decades, the number of wildfires and the surface burned has increased in most countries of the Mediterranean region. Burned landscapes have become a prominent feature of many areas, and forest fires have become a major concern for politicians and the general public. Although fires have been present in the Mediterranean region for millennia, it is likely that changes in land use brought about by industrialization and/or other socioeconomic changes may have affected when;where, how big, how frequent, and how intense these fires are. Similar changes in pattern, extent, and intensity of fire may have also occured in other regions with Mediterranean-type climate. Until now, in most countries fire suppression is the main policy and large and increasing sums are spent every year to fight fires. To introduce new policies that would reduce fire risk and/or its impacts, it is necessary to have a good understanding of how fire affects the structure and functioning of ecosystems. The purpose of this book is to evaluate the main ways in which fire affects ecosystem properties in Mediterranean-type areas, in particular those from the Northern Hemisphere, and what ecological principles management policies should take into account to reduce fire related hazards. A rich variety of vegetation types covers the landscapes of the Mediterranean region. L. Trabaud (Montpellier, France) reviews the postfire vegetation dynamics of different community types from studies done across the Mediterranean basin. The conclusion that emerges is that plant recovery is rapid and that the prefire community is restored mainly from v

6 vi Preface endogenous sources. Thus, it seems that most vegetation types are well adapted to overcome the effects of fire. Unlike in the other Mediterranean-type regions of the world, in Chile there is no history of fires associated with lightning. Nevertheless, humanmade fires are common today. Because of this lack of history, the comparison of the responses to fire of the Chilean matorral with those of other Mediterranean-type areas with a history of lightning fires (E. Fuentes, A.M. Segura, and M. Holmgren, Santiago, Chile) could help us understand the role of fire in the selection of plant adaptive traits. Among the various components of the fire regime, the relationship between fire intensity (i.e., the total energy released during burning), and plant response is difficult to study either because determining the intensity of a wildfire at a specific place is not easy or because modifying it in experimental fires at scales larger than what can be done with a burner is complicated, J.M. Moreno and W.C. Oechel (Madrid, Spain, and San Diego, CA, USA) present the results of a manipulative experiment in which fuel load of a southern Californian chaparral was changed to produce different fire intensities. They show that increased fire intensity can have profound direct and indirect effects on the responses of the plant to fire. The information available on postfire animal dynamics from the various Mediterranean-type areas of the world is still rather limited. This is reviewed by R. Quinn (Pomona, CA, USA), in particular for small mammals, showing that the pattern is not similar for all Mediterraneantype areas. Additionally, he presents results on the role of animals on plant development from experiments conducted in southern California. He shows that herbivory, as exemplified in the case of Ceanothus crassi /olius, exerts a powerful influence on the postfire plant recovery process. Fire alters the physics, chemistry, and biology of soil and directly or indirectly contributes greatly to modify the nutrient status of the soil. The relative impact of fire on soils in Mediterranean-type areas is magnified by the fact that fires occur in steep and poor soils. N.L. Christensen (Durham, NC, USA) reviews how fires have an impact on the soil, and points out some of the gaps we have in this area. Precipitation is limited in Mediterranean-type areas. Hence, water is a limiting resource, not only for plants but also for people. Understanding how fire affects hydrology (S. Rambal, Montpellier, France) is critical in these areas since fires affect an increasingly large surface every year. This is even more compelling in light of impending climate change, as the combination of increased temperature and reduced precipitation may make water more limiting, which may further increase fire risk and, therefore, the surface affected by it. Fires flourish where specific types and spatial arrangements of vegetation (i.e., fuel structure) occur. Fire, in turn, affects both the structure and spatial arrangement of the vegetation. Although the relationship

7 Preface vii between fire and vegetation structure is better known, we know little about the interactions between fire and the structure of the landscape. F.W. Davis and D.A. Burrows (Santa Barbara, CA, USA) provide a modeling tool to explore these relationships. They show that their model can help in understanding the dynamics of landscapes affected by fire and under strong human pressure. Although in many Mediterranean-type areas there are a large number of fires, just a small percentage accounts for a very large fraction of the total area burned, and is responsible for the greatest losses in natural and human values. Designing a management strategy to reduce the occurrence of such catastrophic fires is a priority. To do so, we need to know in detail the impacts associated to various types of fires. P.J. Riggan and colleagues (Riverside, CA, USA) use the extensive knowledge from the San Dimas experimental forest to evaluate the risks associated with fires occurring at different stages of development of the chaparral and under different conditions. Their analysis provides the basis for a management policy that should include the use of fire to reduce fire hazard. Understanding the role of fire in the Mediterranean region and how it can affect the conservation of its fauna, flora, and landscapes is critical, given the current trend in land use and increasing losses due to wildfires. Z. Naveh (Haifa, Israel) discusses the beneficial and detrimental effects of fire. He provides the elements for designing a management policy directed at the conservation of our environment. This book was inspired by a postgraduate course held in Valencia (Spain) under the auspices of Universidad Internacional Menendez Pelayo. We greatly appreciate the support of UIMP and its promotion of a friendly and efficient environment conducive to productive discussion and information exchange among the authors, students, and other interested parties. Jose M. Moreno Walter C. Oechel

8 Contents Preface Contributors v xi 1. Postrrre Plant Community Dynamics in the Mediterranean Basin Louis Trabaud 1 2. Are the Responses of Matorral Shrubs Different from Those in an Ecosystem with a Reputed Fire History? 16 Eduardo R. Fuentes, Alejandro M. Segura, and Milena Holmgren 3. Fire Intensity as a Determinant Factor of Postfire Plant Recovery in Southern California Chaparral 26 Jose M. Moreno and Walter C. Oechel 4. Animals, Fire, and Vertebrate Herbivory in Californian Chaparral and Other Mediterranean-Type 46 Ecosystems Ronald D. Quinn 5. The Effects of Fire on Physical and Chemical Properties of Soils in Mediterranean-Climate Shrublands Normal L. Christensen. 79 ix

9 x Contents 6. Fire and Water Yield: A Survey and Predictions for Global Change 96 Serge Rambal 7. Spatial Simulation of Fire Regime in Mediterranean-Climate Landscapes 117 Frank W. Davis and David A. Burrows 8. Perspectives on Fire Management in Mediterranean Ecosystems of Southern California 140 Philip J. Riggan, Scott E. Franklin, James A. Brass, and Fred E. Brooks 9. The Role of Fire and Its Management in the Conservation of Mediterranean Ecosystems and Landscapes ZevNaveh 163 Index 187

10 Contributors James A. Brass Fred E. Brooks David A. Burrows NASA Ames Research Center Ecosystem Science and Technology Branch Moffett Field, CA 94035, USA Department of Plant Pathology University of California Riverside, CA 92521, USA Environmental Systems Research Institute 380 New York Street Redlands, CA 92373, USA Norman L. Christensen Frank W. Davis School of the Environment Duke University Durham, NC 27708, USA Department of Geography University of California Santa Barbara, CA 93106, USA xi

11 xii Scott E. Franklin Eduardo R. Fuentes Contributors High Spring Avenue Santa Clarita, CA 91321, USA Departamento de Ecologfa P. Universidad Cat6lica de Chile Casilla 114-D Santiago Chile Current address: United Nations Development Programs One United Nations Plaza New York, NY 10017, USA Milena Holmgren Jose M. Moreno Zev Naveh Walter C. Oechel Ronald D. Quinn Departamento de Ecologfa P. Universidad Cat6lica de Chile Casilla 114-D Santiago Chile Departamento de Ecologia Facultad de Biologia Universidad Complutense Madrid Spain Faculty of Agriculture and Engineering Technion, Israel Institute of Technology Haifa Israel Department of Biology San Diego State University San Diego, CA 92182, USA Department of Biological Sciences California State Polytechnic University Pomona, CA 91768, USA

12 Contributors xiii Serge Rambal Philip J. Riggan Alejandro M. Segura Louis Trabaud Centre d'ecologie Fonctionnelle et Evolutive Centre Emberger CNRS Route de Mende B.P Montpellier France USDA Forest Service Pacific Southwest Research Station Forest Fire Laboratory 4955 Canyon Crest Drive Riverside, CA 92507, USA Departamento de Ecologia P. Universidad Cat6lica de Chile Casilla 114-D Santiago Chile Centre d'ecologie Fonctionnelle et Evolutive Centre Emberger CNRS Route de Mende B.P Montpellier France