Air Plants

H. Benzing David

Description

Often growing far above the ground, "air plants" (or epiphytes) defy many of our common perceptions about plants. The majority use their roots only for attachment in the crowns of larger, usually woody plants-or to objects such as rocks and buildings-and derive moisture and nutrients from the atmosphere and by collecting falling debris. Only the mistletoes are true parasites. Epiphytes are not anomalies and there are approximately 28,000 species-about 10 percent of the higher or vascular plants-that grow this way. Many popular houseplants, including numerous aroids, bromeliads, ferns, and orchids, rank among the most familiar examples. In Air Plants, David H. Benzing takes a reader on a tour of the many taxonomic groups to which the epiphytes belong and explains in nontechnical language the anatomical and physiological adaptations that allow these plants to conserve water, thrive without the benefit of soil, and engage in unusual relationships with animals such as frogs and ants.Benzing's comprehensive account covers topics including ecology, evolution, photosynthesis and water relations, mineral nutrition, reproduction, and the nature of the forest canopy as habitat for the free-living and parasitic epiphytes. It also pays special attention to important phenomena such as adaptive trade-offs and leaf economics. Drawing on the author's deep experience with epiphytes and the latest scientific research, this book is accessible to readers unfamiliar with technical botany; it features a lavish illustration program, references, a glossary, and tables.

Sujets

• Sciences et techniques
• Reference work
• Trees

Informations

• Publié par: Cornell University Press
• Date de parution: 15 juin 2012
• Nombre de lectures: 0
• EAN13: 9780801463877
• Langue: English
• Poids de l'ouvrage: 3 Mo

Extrait

AIR PLANTS

AIR PLANTS EPIPHYTES AND AERIAL GARDENS

David H. Benzing

Comstock Publishing Associates

a division of Cornell University Press ithaca and london

Copyright © 2012 by Cornell University

All rights reserved. Except for brief quotations in a review, this book, or parts thereof, must not be reproduced in any form without permission in writing from the publisher. For information, address Cornell University Press, Sage House, 512 East State Street, Ithaca, New York 14850.

First published 2012 by Cornell University Press

Printed in the United States of America

Library of Congress Cataloging-in-Publication Data

Benzing, David H.  Air plants : epiphytes and aerial gardens / David H. Benzing.  p. cm.  Includes bibliographical references and index.  ISBN 978-0-8014-5043-3 (cloth : alk. paper)  1. Epiphytes. I. Title.  QK922.B45 2012  581.6'3—dc23 2011046584

Cornell University Press strives to use environmentally responsible suppliers and materials to the fullest extent possible in the publishing of its books. Such materials include vegetable-based, low-VOC inks and acid-free papers that are recycled, totally chlorine-free, or partly composed of nonwood fibers. For further information, visit our website at www.cornellpress.cornell.edu.

Cloth printing

10 9 8 7 6 5 4 3 2 1

Pursuing a career that combines daily immersion in a much-beloved subject with curious and talented undergraduates and engaging colleagues around the world is nothing short of rare good fortune. I dedicate this book to the possibility that what I have been able to enjoy will endure and, most important, that the natural world will survive for individuals lucky enough to be similarly captivated by its beauty and mystery.

Contents

Preface xi Acknowledgments xiii  1. What Is an Epiphyte?1 Getting to Know the Epiphytes 2 Body Plans 8 The Epidermis 11 Other Notable Features of the Epiphytes 11 Starting at the Beginning 12 Geological History 14 Geographic Distribution 15 Use by Humans 17 Conservation 18

 2. The Types of Epiphytes and Their Evolutionary Origins The Free-Living Epiphytes 23 The Biological Underpinnings of Epiphytism 33 How Epiphytism Evolved 34 The Taxonomic Affiliations of the Epiphytes 37 Genetic Heritage and Evolutionary Options 37 Epiphytism and Speciation 39

 3. Epiphytes in Communities and Ecosystems The Nature of Aerial Habitats 43 Mineral Nutrients 45 Water 47 Light 49 Epiphytes as Members of Communities 53

42

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viii

Contents

Random Factors Also Structure Communities 54 Ecological Succession 56 What Makes a Tree a Host for Epiphytes? 58 How Epiphytes Can Impact Their Hosts 59 Nutritional Piracy 61 Additional Ways That Epiphytes Harm Their Hosts 63 Manifold Effects on Ecosystems 64

 4. Water Management66 Variations on Basic Themes 66 How Biological Structure Relates to Function 67 Water Management 68 How Epiphytes Cope with Drought 71 Drought Avoidance 73 Leaf Economics 73 Roots 75 Leaves as Proxies for Roots 78

 5. Photosynthesis and Mineral Nutrition The Photosynthetic Syndromes 83 C 3 85versus CAM-type Photosynthesis Light and Adaptive Growth 87 Mineral Nutrition 89 The Mistletoes 94

83

 6. Reproduction and Other Interactions with Animals Pollination 98 Fruits and Seeds 102 Asexual Reproduction 105 Plant Defenses 106 Ants and Epiphytes 106 Termites 110 Leafy Tanks and Phytotelms 112 Case Studies 114

 7. The Epiphytic Monocots119 Orchidaceae 121 The Vegetative Body 121 Reproduction and Speciation 123 The Adaptive Types 126

98

Contents

Bromeliaceae 127 Bromeliads versus Orchids 129 Adaptations for Epiphytism 129 Hemi-epiphytism 132 The Atmospheric Bromeliads 134 Araceae 136 Amaryllidaceae and Additional Families in Order Liliales  8. The Epiphytic Eudicots142 Cactaceae 143 General Characteristics 143 Adaptations for Epiphytism 145 Evolutionary History 145 Ecology 148 Reproduction 148 Ericaceae 149 Adaptations for Epiphytism 150 Epiphytism and Speciation 151 Reproductive Biology 151 Horticulture 151 Gesneriaceae 152 Adaptive Variety 153 Evolutionary History 153 Reproductive Biology 155 Rubiaceae 156 Melastomataceae 158 Apocynaceae 159 Solanaceae 161

 9. The Pteridophytic Epiphytes162 The Major Groups of Pteridophytes 166 The Ferns 167 The Lycophytes 179

10. Miscellaneous Epiphytes182 Piperaceae 182 The Carnivorous Epiphytes 184 The Stranglers and Other Primary Hemi-epiphytes 187 The Gymnosperms 189 Additional Oddities 190

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