Roelof A. A. Oldeman

Forests: Elements of Silvology

With 215 Figures

Springer-Verlag Berlin Heidelberg New York London Paris Tokyo Hong Kong Barcelona

Professor Dr. RoELOF A.A.OWEMAN Gen. Foulkesweg 76 6703 BX Wageningen The Netherlands

ISBN·1J, 978·3·642·75213·1 e·ISBN·13, 978·3·642·75211·7 DOI,10.1007/978·3·642·75211·7

LibraryofCongress Ca taloging-in-Publication Data. Oldeman. Rodof A. A, 1937- Elemenlsofsil. vology / Roclof A. A. Oldcman. p. an. Includes bibliographical references(p.).ISBN-13: 978-3-642 _7S213_1{U.S. :alk.paper) I. Forest ecology.2. Forests and forestry. I. Title.QK938.F6037 1990 581.5' 2642-dc2Q 90-9680

This work is subject to copyright. All rights are reserved, whetherth" whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in other ways, and storage in data banks_ Duplication of this publication or parts therwris only permiUed under the provisions of the Gennan COpyright Law ofStptembcr 9, t965, in its current version, and a copyright fO!(: must always be paid. Violations fall under the pro,;ecution act of the Gennan Copyrighl Law.

C Springer-Verlag Berlin Heidelberg 1990 Soft.<;ove. reprint of the hardeo"'" 1st edition 1990

The usc of registered names, trademarks, etc. in this publication does nOI imply, even in theabscna: of a specifiestatemcnt, that such names are exempt from the relevam protective laws and regula­tionsand therefore free for general usc.

2\31/3145-543210 - Printed on acid-free paper

I dedicate this book to my wife JiJiL HELDER

with feelings that would fill a book too

Laforet, c'est la collectivite immense 012 la vie besogne sans blUit, 012 un travail gigantesque s'accomplit et se poursuit sans trepidations, sans fracas et sans poussiere; 012 de magnifiques choses visibles sortent de menues choses invisibles.

H. Biolley 1930, dans: Forets de mon Pays

No hay que ponerse ante el Universo suspicaz como un aldeano. El positivismofue unafilosofia aldeana.

J. Ortega y Gasset 1929, i, Que es fiIosofia?

Fear no alder black! Heed no hoary willow! Fear neither root nor bough! Tom goes on before you.

Tolkien 1954, The Lord of the Rings

"Ik geloofhet niet ", zei heer Ollie zorgelijk. "H et is jullie eigen schuld, bedoel ik. Ik geloof dat jullie er aileen uit kunnen komen als je het bos met lUst wilt laten. Dat geloofik."

Marten Toonder 1971, De Kwinkslagen

Preface

In matters offorest ecology, it has already become impossible to produce a comprehensive state of the art without omitting many times more than one text can possibly contain. The sheer historical richness of sources alone would account for this, but it is compounded by a quarter of a cen­tury of recent research having yielded an amazing richness of facts, view­points and models. I have actively participated in the research effort of these five-and-twenty years, and it has therefore been my intention to trace back the approaches that now exist to those admirable pioneers of a still somewhat simpler period, roughly between the years 1950 and 1970, who laid the basis for the actual and seemingly confusing deluge of pub­lications in this field.

It is my great concern that scientists, perhaps in sheer desperation, will choose among methods instead of returning to the forests, where each method makes sense in its own limited way. Are we ever going to be able to arrive at one science offorests, in which different approaches appear as means to cast light on special aspects instead of competing as exclusive roads towards the truth? Some of the most valuable books that appeared in the 1980's increase my concern by too exclusively emphasizing such theories as population biology, architectural analysis or computer-simu­lated production ecology (cf. Table 2.1). In our preface to "Tropical Trees and Forests: an Architectural Analysis", which appeared in 1978, Halle, Tomlinson and myself already gave an overview of such works one de­cade earlier.

The choice of one limited approach has been frequent in the history of science as a means to dig deeper in a special field of research. The ratio­nale for concentrating upon one method is, that it may allow us to finally reach the universal core of the matter if we dig deep enough. Present -day conditions of research emphasise this tendency, because financing bodies insist on "research priorities" that are not too difficult to grasp. As a mirrored image of the scientific arguments fornarrowing down research to such priority lines, we find the so-called "problem-orienteq research". This leads to the tackling of practical problems showing a highly visible profile, often manifested today by intensive media coverage. Acid pre­cipitations, deforestation ofthe humid tropics, rural forestry in dry tropi­cal regions or wildlife conservation are examples of such issues.

Political lobbies defining problem statements and scientific lobbies translating these statem>ents into scientific questions, according to the

VIII Preface

past successes of a certain school of thought, then combine their powers. These mighty forces exert high pressure upon the minds of scientists to make choices including methods easy to explain to a large public and re­search projects that carry little risk of generating even the impression of waste of public moneys. The same forces largely occur in privately fi­nanced research. Scientific gurus, political bankers, the media and a re­search field covered with a rich but very confusing array of theories and models practically drive the young researcher towards narrow options and specialisations.

This reasoning and this situation may appear quite healthy to those who hope that in this way - finally! - science may become fit to be man­aged. However, if this means that scientists and their methodological tools are to be organised by managers, so as to solve all successive prob­lems that humanity may meet on its way, this is certainly an illusion. The success story of European forestry research is an illustration ofthis point.

For two centuries European forestry research has been "problem­oriented". It started by solving problems in the fields of reclamation of de­graded lands and wood production, both by the planning and design of man-made forests and tree plantations. Later, it incorporated the use of older forests as biotopes for wild plants and animals and the principles of farmers' forestry. In each European country, the emphasis was placed on the most urgent national problems. Fashions in forestry succeeded each other after widely publicised local success stories: the Central European Plenterwald, the British and Dutch reafforestion ventures, the French conversion of coppice with standards into high forest or the Scandinavian large-scale coniferous forest management systems are some examples.

The whole terminology and the array of concepts in forestry research bear witness to this blending of practical management problems and aims with gradually added ecological notions. The word forest stand, meaning a management unit like an agricultural field, came to indicate any small to intermediate-sized surface covered by trees or forest. When a stand grows up, it arrives first at a pole phase, then at a ripe phase. Both denote eco­logical states of forest development, but the first one is also apt to yield poles to farmers, whereas the last phase is ripe for the harvesting of sawn­wood. Average stand properties from the outset were calculated from tree properties directly linked to wood production, such as tree height and diameter. Only later were the ecological implications of these variables perceived.

European forestry research, including the work done by European re­searchers in other parts of the world, thus developed into an onion-like complex of knowledge, in which layer after layer of special, probl'em­oriented concepts became superposed upon their only communication point at the base, whence these layers were fed from the roots of practical problem statements and natural sciences. At the present day, both roots have proliferated. There are numerous unprecedented forest problems in the world and there is an unprecedented advance and diversification in

Preface IX

basic sciences. None of the layers around 1970 contained the answers to problems like the impact of pollution, semi-natural tropical rainforest management, the use of strict forest reserves, genotype bank forest man­agement, tropical rural energy forests or woodlots, and tens of others. The inputs from natural sciences were, at the same time, insufficient to rapidly add other layers of problem-solving concepts and so prolific that they started to identify new problems, even before these became manifest in day-to-day forest management.

Authors like Briinig (e.g. in Wiersum 1984) like to point out that the concepts united in this way during two centuries of European forestry re­search have become completely insufficient to solve today's forestry problems. Is this whole priceless body of knowledge, then, to be con­sidered as a brake to progress rather than as an asset? It is my conviction that this entirely depends on its use. This, again, depends on the choice that researchers will make. If, on the one hand, the seemingly easiest way is chosen, research and management priorities will be defined in the tradi­tional way, and this will lead to a lack of solutions fortoday's and tomor­row's forestry problems, and to sterilisation of progress in forestry science. If, on the other hand, this complex of knowledge is used as a treasure house, from which selected concepts and facts are used as judged necessary by courageous young researchers who do not fear the uncer­tainty ofleaving well-trodden paths, progress in both forestry and forest science will result.

World-wide, this state of affairs is confirmed. The development of forest science cannot be conceived any further without the new notions, concepts and facts that saw the light in many countries, such as Mexico, Japan, the USA, Malaysia, Australia, Suriname or the Cote d'Ivoire, to name only a few. National or European forest research still yields valu­able and necessary sources of knowledge, but any serious basis for ad­vanced forest science will have to draw upon all that has been thought out in this field, the world over. This means an important shift in focus as well as a shift in gear, because a wider viewpoint also requires a lot of high­quality work.

This short tale on research in forestry could be paralleled with anal­ogous case histories in various fields of botany, zoology, soil science and ecophysiology, all with long scientific traditions linked to human problems. Botany was an adventitious root of pharmacy, zoology of hunting and cattle sciences, and soil science or ecophysiolo­gy can be neatly linked to agriculture. None of the managers in these fields, the pharmacists, the hunters or the farmers, has ever been able to foretell the development in these sciences, nor to plan and regulate the workings of the scientific brains that made it possible. But all have benefited by these unpredictable and highly profitable scientific developments, most often generated only because some scientist had dropped the narrow viewpoints of immediate useful­ness.

x Preface

In other words, it proved to be necessary to develop the intelligent pro­cessing of information and knowledge in itself, before intelligent prob­lem-solving action could be improved. Science in this way has become the contemporary intellectual toolfor ranging information according to or­derly lines of knowledge and insight. Scientific activity is an investment, both in the development of theory-building brains and in the accumula­tion of ordered and falsifiable theories or models. In this, it is an autono­mous venture with its own rules. Scientific problem-solving is quite differ­ent from practical problem-solving. But adequate scientific models, on condition thatthey are well translated in everyday language, are one of the roots of high-quality solutions of practical or other human problems.

My diagnosis of the state of affairs in the sciences offorests has led me to undertake a long and hazardous voyage in this realm of the scientific mind. My ambitious aim was to establish a sort of map of this field ofre­search, with signposts allowing the user to find his or her way towards more details, into greater depth, or from the scientific field to the practical aspects. Because all forest researchers and all foresters have one thing in common, i.e. some notion about the nature of forests, these notions be­came the focus of attention.

The complexity of forests is such that forest ecology as a natural science is on a par with such sciences as brain biology or the science of coral reefs. In a few hectares of forest, whereverin the world, the number of organisms lies between millions and billions, interacting with each other and within many abiotic gradients in a never-ceasing, swarming, highly dynamic and nevertheless organised play of feedbacks, life and death. There is only one computer able to process all the data within such a system: that computer is the forest itself. It was therefore necessary to order and select data according to the notions invented long ago, but made operational in new and efficient ways more recently, of hierarchical systems analysis. They allowed sketching a general framework, at the same time defining the entries into special approaches or more detailed aspects.

Because scientists have absolute freedom to choose the limits of sys­tems, subsystems or supersystems in systems hierarchies, a decision had to be taken as to this choice. This decision was consciously made in favour of directly visible limits, liable to be mapped graphically with simple means. Many of the calculation models presented nowadays do the in­verse by superposing a geometrical grid, in two or more dimensions, over an ecosystem and localising limits through calculated values for proper­ties of grid squares, cubes or abstract spaces. This is beingjustified fortwo reasons. The first one is the necessity of" quantitative" models, a term mo­nopolised formerly by statisticians and nowadays by computer-model builders. The second reason is the reduction of data needeq to keep mod­els manageable.

I concur with the gist of both arguments, but not with the way to solve them. For such "superposed" models, a doubt always remains in my mind

Preface XI

whether some essential feature of the forest has been overlooked, so that the models may work but miss the point in explaining the working of the forest itself. A spectacular example of this having happened is the cen­tury-old controversy on the existence of "layers" or "strata" in the forest, which can be solved simply by looking at scale-drawings with a mind un­biased by pre-existing models on paper, as is shown in Chapter 6 of the present book. An understanding of forests in simple terms, which can be immediately validated in the field with simple means, according to my conviction has to precede and not to follow the establishment of com­puted simulation models. This is often admitted, but too seldom done in a thorough way.

Therefore, in this book the whole matter of forest ecosystems analysis has been taken up again from the base, i.e. the direct observation of forests and their component organisms. The original meaning of scien­tific terms has been explained wherever possible, and a large number of examples from over the whole world has been reproduced and surveyed. The vocabulary for distinguishing systems and their states had to be com­pleted, and this has led to the creation of some neologisms and new terms, which I hope the reader will be able to assimilate easily and without grum­bling, once their usefulness is conceded.

Once the map of forest ecosystems analysis had been established, two series of "signposts" have been added during the writing of the text. The first set points to the links with forestry and silviculture, by giving refer­ences to textbooks and articles or in the form of tables and illustrations, comparing terms and their meaning. The second set of signposts includes the sources where information can be found on the different schools of ecological and forest ecosystem research. If textbooks exist, detailed ex­planations were superfluous. In this way, compilation was avoided as far as possible and desirable.

Among the data presented, many are unpublished or have in many cases not yet appeared in overviews or textbooks. I obtained them from the numerous reprints that I had the privilege to receive these last years, from additional reading and from personal communications in some cases. My sources also include numerous unpublished doctoral and mas­ter's theses, and mimeographed documents from institutions in those parts of the world where the scientific culture does not include the print­ing of scientific results according to the rules prevailing in Europe or the USA. Graduate students and people doing doctoral research have im­pressed me, during the twelve years that I have been teaching, as having particularly free, open and keen minds. I have come to fully appreciate the continental European custom of publishing Doctor's theses.

The extensive use of what sometimes is called the "grey literature", outside the more prestigious scientific circuits, allowed me to find many scientific eye-openers and to use and make public many results of studies which would otherwise have ended too often in the grave of the seldom consulted, long rows of theses in a University library. Some of the theses

XII Preface

cited were made intentionally in order to find facts needed for this book. Such studies then often concerned forests close at hand, i.e. in the Nether­lands. Finally, each thesis contains a bibliography which may be ordered from the library where it is stocked, as a photocopy. This strengthens the signpost function of such works. I only regret that I did not have ready ac­cess to more theses, particularly outside the Universities of Montpellier and Wageningen, and some German and tropical ones.

During the adventurous voyage, which was the writing of this book, and even before, I met some of the most brillant, old and young minds of our century. This voyage fully confirmed my earlier conviction, that man y more unconventional ideas are spawned in our scientific field than is commonly realised, but that the occurrence of crazy or cheating scientists is so extremely rare that it can in no way justify the myths on this subject that are common currency in popular belief. I do hope that the text, such as it has become, will convey this sense of excitement and richness to its readers and, most of all, that they will discover or rediscover the forest through the models presented.

ROELOF A. A. OLDEMAN

Acknowledgements

This book has been long in the cooking, and many people have helped me reach the stage where it could grow from a set of ideas into a set oflec­ture notes and finally into the present text. Now is the time to send the manuscript to the publisher, before I finish reading Prigogine and Stenger, Hofstadter or Egolfs Bakuzis' incomparable lecture notes and, who knows, might have to start all over again. Those who contributed to the ideas in the present book cannot all be mentioned on this page, but even if more are omitted than acknowledged explicitly, please let all ac­cept my sincere thanks.

I learned a lot about what decision-makers, managers, bankers and forest-lovers want to know about forests from people met during my TROPENBOS-time. My thanks for this go to people like Dr. Van Spie­gel, Mr. Heering, Dr. Ross, Mr. Van Dam, Dr. Clement, and UNEP's Dr. "Chuck" Lankaster. It is the latter who, in a discussion at the Hague, doubted whether the concepts of silvology and silvonomy would ever be printed. Here is one of them. In the same line of thought, my thanks go to WNF's Mr. Van der Giessen, FERN's Prof. Bourdeau, lIED's Prof. Poore and Mr. Rietbergen, AUW's Prof. van Maaren, GFF's Mr. Meester, Mr. Van der Meijden of SBH, and IUCN's Dr. Sayer.

Where are the scientific roots? I still think that the seed formed in my mind during a discussion with Dr. lean-Louis Guillaumet at the Paris Museum,just before my departure to Ecuador in 1974. I thank him truly, and also those with whom I could discuss these matters since then, for in­stance Ing. Cafiadas Cruz, Prof. Bourliere, les Hladik, Dr. Hadley, Prof. Mutch, Prof. De Wit, Dr. Whitmore, Dr. Koop, Prof. Barkman, Prof. Baudiere, Dr. Ashton, Prof. Kojima, Prof. Ohkubo, Dr. Aivim, Mr. Cao, Prof. Hari, Prof. Tomlinson, Prof. Leikola, Dr. Saleh, Prof. Roux, Dr. Bancilhon, Prof. Soemarwoto and his wife, Dr. Ng, Prof. Mlinsek, Dr. Rossignol, Prof. Schutz, Ms. Teller, Prof. Mayer, M.Dubost, Prof. Szu­jecki, Dr. Charles-Dominique, Prof. Oliver, Dr. Gasc, Dr. De Granville, Prof. Fanta, Dr. Maitre, Dr. Sombroek, Prof. Kio, Dr. Leeuwenberg, Dr. Huxley, both Dr. Lescure and Dr. Lescure, Prof. Kira, Prof. Sarukhan, Prof. Gomez-Pompa, Ora. Monasterio, Prof. Balslev, and so many others.

Without the encouragement of ESF's FERN, formulating the need for a state of the art in forest ecosystems research, this book might not

XIV Acknowledgements

have been written. It has not become a state of the art, however, in the usual sense. My special thanks go to Dr. Rolfe A. Leary (IUFRO 06.09) without whom the subject of methodology and philosophy of forest re­search would not have been made explicit, to Dr. Peter Raven (Missouri Botanical Gardens) for his contribution on yellow tropical flowers, to Dr. Pieter Schmidt, without whom the paragraphs on tree production would have looked quite different, to Prof. Francis Halle for an ever-continuing collaboration although he doesn't agree with the diverse nature of sec­ondary forest as postulated here, and to Ir. Paul Romeijn for his welcome and sharp comments to the speciation and selection paragraph. Prof. Eberhardt Briinig I thank for having been always and frequently stimu­lating in his own thorough, assertive and far-seeing way, whereas I am sincerely grateful to Ir. Jaap Kuper, Her Majesty's Opperhoutvester, for having unearthed the Backman publications.

The former Department of Silviculture and Forest Ecology at Wage­ningen University has suffered much by, but also contributed significant­ly to, the growth of this book. I thank all researchers and particularly the promovendi and students who took the trouble to produce a whole stack of useful comments. And I can never thank enough Ms. Boudewijn and Mr. De Bruijn, without whose whole-hearted cooperation this book would not have obtained its final shape.

Wageningen,May1990 ROELOF A. A. OLDEMAN

Contents

First Part: Introductory Matter - Summary

1

1.1 1.2 1.3

2

2.1 2.2 2.3 2.3.1 2.3.2 2.3.3 2.3.4 2.4 2.4.1 2.4.2 2.4.3 2.4.4 2.4.4.1 2.4.4.2 2.4.4.3 2.4.4.4 2.4.4.5 2.4.4.6

The Forester as a Green Designer ..................... .

Forestry is Not Self-Evident. ........................ . Silviculture ....................................... . Silvology ......................................... .

Build-Up and Use of Theories ........................ .

Some Concepts ................................... . Criteria for Modelling .............................. . The Choice of Systems: A Game Without Frontiers? ... . Limits ............................................ . Grids, Pixels and Power of Resolution ................ . Ground Truth ..................................... . The Eye and the Natural Limits ..................... . Hierarchies ....................................... . Added Information ................................ . Components and Compartments .................... . Disturbance and the Role of Hazard ................. . Examples of Hierarchies ........................... . Continuity of Criteria .............................. . Use of Numerous Levels ........................... . Architecture as the Prime Criterion .................. . Intentional Omission of Levels ...................... . Precision of Limits ................................. . Flexibility and Completeness ....................... .

Second Part: Forest Components - Summary

3

3 6 7

9

9 10 12 12 12 14 14 16 16 19 20 20 20 21 21 22 23 23

3 Trees ........................................ '. . . . . . 27

3.1 What Is a Tree? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 3.2 The Life Cycle of Trees: Architecture .................. 28 3.2.1 The Seedling Period ................................ 30 3.2.2 The Model-Conform Period ......................... 30 3.2.3 Metamorphosis and Programmed Adaptation. . . . . . . . . . 37

XVI

3.2.4 3.3 3.3.1 3.3.2 3.3.3 3.3.4 3.3.5 3.3.6 3.4 3.4.1 3.4.1.1 3.4.1.2 3.4.1.3 3.4.1.4 3.4.2 3.4.2.1 3.4.2.2 3.4.2.3 3.4.2.4 3.5 3.5.1 3.5.2 3.5.3 3.5.4 3.5.5 3.5.6 3.6 3.6.1 3.6.2 3.7 3.8 3.8.1 3.8.2 3.8.3 3.9

Contents

Reiteration and Opportunistic Adjustment. . . . . . . . . . . . . 41 The Life Cycle of Trees : Root Architecture. . . . . . . . . . . . . 45 Architectural Criteria in Root Growth . . . . . . . . . . . . . . . . . 45 Seedling Roots ..................................... 50 Roots in Model-Conform Trees ...................... 50 Roots in Metamorphosing Trees. . . . . . . . . . . . . . . . . . . . . . 53 Roots in Reiterating Trees ........................... 53 Specialised Roots. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Application of Architectural Tree Properties ........... 56 Provoking Reiteration for Shoot Production ........... 56 Coppicing ......................................... 56 Pollarding ......................................... 59 Lopping........................................... 59 Pruning, Clipping, Trimming ........................ 63 Provoking Reiteration for Vegetative Multiplication .... 63 Cuttings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Grafting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Layering or Marcotting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Root Suckers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 The Life Cycle of Trees : Energy and Nutrients ......... 67 ~oncepts .......................................... 67 Production Systems and Functions ................... 69 Production and Function of Organs and Tissues. . . . . . . . 71 The Sapstream ..................................... 78 Stimulation, Stress and Sapstream Feedbacks .......... 80 Cambial Activity: A Parameter for Vitality and Production 81 The Life Cycle of Trees: Cycles and Variants........... 83 The Backman Theory ............................... 84 Modulated Life Cycle Curves ........................ 93 The Life Cycle of Trees: Proportional Diagnosis. . . . . . . . 98 The Life Cycle of Trees: Populations .................. 103 Trees as Populations of Organs or Crownlets ... . . . . . . .. 104 Some Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 105 Transfer of Functions ............................... 106 Between Trees and Forests ........................... 108

4 Forest Components Other Than Trees . . . . . . . . . . . . . . . . .. 109

4.1 Introduction: The Trees and the Others ................ 109 4.2 Shrubs ............................................. ' 110 4.3 Herbs ............................................. 113 4.4 Lianes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 119 4.5 Epiphytes .......................................... 124 4.6 Monocotyledons ................................... 127 4.6.1 Architecture of Monocotyledons ..................... 131 4.6.2 Production in Monocotyledons ...................... 135

Contents XVII

4.6.3 Ratios and Proportions in Monocotyledons . . . . . . . . . . .. 136 4.6.4 Some Monocotyledonous Groups Important for

Silviculture ........................................ 137 4.7 Cryptogamous Plants ............................... 138 4.8 Animals ........................................... 142 4.8.1 General Characteristics and Ecological Functioning .... 142 4.8.2 Mammals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 143 4.8.3 Birds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 144 4.8.4 Reptiles, Amphibians and Fish. . . . . . . . . . . . . . . . . . . . . .. 145 4.8.5 Insects and Other Arthropodes .. . . . . . . . . . . . . . . . . . . . .. 145 4.8.6 Worms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 151 4.9 Between Forests and Non-Arborescent Components. . .. 152

Third Part: Forest Ecosystems - Summary

5 Forest Eco-Units ................................... , 155

5.1 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 5.1.6 5.1.7 5.2 5.2.1 5.2.2 5.2.3 5.2.4 5.2.4.1 5.2.4.2 5.2.4.3 5.2.5 5.2.5.1 5.2.5.2 5.2.5.3 5.2.6 5.3 5.3.1 5.3.2 5.3.3 5.3.4 5.3.4.1 5.3.4.2 5.3.4.3

What are Forest Eco-Units? ......................... , 155 Elements of Definition .............................. 155 Spatial Limits and Gradients .. . . . . . . . . . . . . . . . . . . . . . .. 156 Temporal Limits and the Zero-Event .................. 159 Eco-Units Are Not Necessarily Even-Aged ............ 161 Eco-Units Are Living Systems but Not Organisms ...... 162 Eco-Units and Silvicultural Design ................... 163 The Behaviour of Forest Eco-Units ................... 165 Development of Forest Eco-Units: Architecture. . . . . . .. 166 General Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 166 The Innovation Phase ............................... 166 The Aggradation Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 170 The Biostatic Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 175 Overview .......................................... 175 The Trees. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 176 Components Other Than Trees. . . . . . . . . . . . . . . . . . . . . .. 181 The Degradation Phase ............................. 186 Overview ................ . . . . . . . . . . . . . . . . . . . . . . . . .. 186 Dynamics Explained ................................ 186 The Zero-Events ................................... 192 Clinical Death of Eco-Units, Size, Succession .......... 195 The Life Cycle of Forest Eco-Units: Root Compartment. 197 Architecture and Horizons. : .................. :. . . . .. 199 Root Occupation Patterns ........................... 202 Root Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 207 The Edaphon and its Compartments .. '.' . . . . . . . . . . .. .. 215 Mycorrhizae ....................................... 216 Other Fungi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 222 Bacteria ........................................... 223

XVIII

5.3.4.4 5.3.5 5.4 5.4.1 5.4.1.1 5.4.1.2 5.4.1.3 5.4.1.4 5.4.1.5

5.4.1.6 5.4.1.7 5.4.1.8 5.4.2 5.4.2.1 5.4.2.2 5.4.2.3

5.4.2.4 5.4.2.5 5.4.2.6 5.4.2.7 5.4.2.8 5.4.3 5.4.3.1 5.4.3.2

Contents

Soil Fauna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 225 Phasic Development of Eco-Unit Root Compartments .. 227 Examples of Eco-Units of Different Size and Nature. . .. 231 Large Eco-Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 231 Treeless Innovation Phase near Montpellier (France) ... 231 Planted Early Aggradation Phase (the Netherlands) . . . .. 234 Aggrading and Degrading Eco-Units (the Netherlands) . 238 Late Innovation Phases, Humid Tropics (Guyanas) ..... 240 Late Aggrading and Degrading Phases (Oyapock, Fr. Guyana) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 246 Large Tropical Eco-Unit Development (Manaiis, Brazil) 247 Eco-Unit Development in Cote d'Ivoire ............... 248 Fragmenting Eco-Unit in Papua New Guinea. . . . . . . . .. 250 Intermediate Eco-Units ............................. 252 Biostasis in Drier Climates (Cote d'Ivoire) ............. 253 Biostasis in Savanna Forest (Bor, Sudan) .............. 255 Aggrading Phase in Marsh Forest (Flevoland, the Netherlands) ................................... 256 Biostasis atthe Forest Limit (Colombian Andes) . . . . . . .. 256 Pine Forest Development in the Appennines (Italy) ..... 259 Early Aggrading Phases in Alsatian Oak Forest (France). 261 Late Aggrading Phase near the Rhine (the Netherlands) . 262 Eco-Units in Old-Growth Douglas-Fir Forest (USA) .... 264 Small Eco-Units .................................... 266 Eco-Unit Development in Bialowieza (Poland) . . . . . . . .. 267 Small Windthrow in Douglas Fir Plantation (the Netherlands) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 270

5.4.3.3 Eco-Unit Development in Tropical Rainforest (Suriname) 270 5.4.3.4 Eco-Units in a Dipterocarp Plantation (Indonesia) . . . . .. 272 5.4.3.5 Eco-Units in Tai Forest (Cote d'Ivoire) ................ 276 5.4.3.6 Eco-Units in a Mixed Hardwood Forest (France) . . . . . .. 279 5.4.3.7 Eco-Units in Mixed Central European Forests ......... 280 5.4.3.8 Eco-Units in Coniferous Japanese Mountain Forests. . .. 282 5.4.3.9 Eco-Units in Fragmenting Oak Forests (Austria) . . . . . . .. 284 5.4.3.10 Eco-Unit Borders (Antilles) . . . . . . . . . . . . . . . . . . . . . . . . .. 287 5.4.3.11 Fusion of Small Eco-Units in Beech Forest

(the Netherlands) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 288 5.4.3.12 Fused Small Eco-Units in Japanese Beech Forest ....... 292 5.4.4 Why Were These Examples Chosen? . . . . . . . . . . . . . . . . .. 294 5.5 Systems Analysis of Forest Eco-Units: The Compartments ,295 5.5.1 What is a Compartment? ............................ 295 5.5.2 Populations as Compartments ....................... 295 5.5.3 Biological Types (Life Forms) as Compartments: . . . . . .. 299 5.5.4 Examples of Population and Life Form Analysis ....... 301 5.5.5 Compartments in Classical Vegetation Science. . . . . . . .. 308 5.5.6 Synusiae as Compartments .......................... 310

Contents

5.5.7 5.5.8 5.5.9 5.5.10 5.5.11 5.6 5.6.1 5.6.2 5.6.3 5.6.4 5.6.5 5.6.6 5.6.7

5.6.8 5.6.9 5.7

XIX

Hoplexols and Transdisciplinary Language. . . . . . . . . . .. 311 Guilds as Compartments ............................ 316 Cohorts as Compartments ........................... 317 Connexus and the Ecological Interaction Fabric. . . . . . .. 317 Tree Compartments and Tree Temperament ........... 321 The Life Cycle of Forest Eco-Units: Production Models. 337 Concepts .......................................... 338 Relation Diagram for an Eco-Unit .. . . . . . . . . . . . . . . . . .. 339 Evaluation ofSilvicultural Measures. . . . . . . . . . . . . . . . .. 344 Biomass Production and Biogeochemical Flows . . . . . . .. 344 Production Models: Some Principles and Examples .... 350 Crop Models and Gap Models ....................... 358 Computer-Linkage Between Architectural and Biogeochemical Models . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 366 Ecological Impellors, Poisons, Chemosilviculture ...... 372 Transfer of Ecological Functions ..................... 382 From Eco-Units to Silvatic Mosaics. . . . . . . . . . . . . . . . . .. 387

6 Silvatic Mosaics .................................... 388

6.1 6.1.1 6.1.2 6.1.3 6.1.4 6.1.5 6.1.6 6.2 6.2.1 6.2.2 6.2.2.1 6.2.2.2 6.2.2.3 6.2.2.4 6.2.2.5 6.2.2.6 6.2.2.7 6.2.3 6.2.3.1 6.2.3.2 6.2.3.3 6.2.3.4 6.2.4 6.2.4.1 6.2.4.2 6.2.4.3

What Are Silvatic Mosaics? . . . . . . . . . . . . . . . . . . . . . . . . .. 388 Elements of Definition .............................. 388 Spatial Limits and Gradients. Succession .............. 389 Temporal Limits and the Shifting Event ............... 393 Silvicultural and Ecological "Normalcy" .............. 394 Silvatic Mosaics Are Living Systems but Not Organisms. 396 Behaviour of Silvatic Mosaics .......... . . . . . . . . . . . . .. 401 The Life Cycle of Silvatic Mosaics: Architecture ........ 402 Definitions of Eco-Units as Subsystems ............... 402 The Installation Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 403 Biotic Remanence .................................. 404 Biotic Reach ofPropagules .......................... 406 Abiotic Impacts and Neo-Mosaics . . . . . . . . . . . . . . . . . . .. 407 Fragmentation ..................................... 408 Eco-Unit Composition. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 408 Apparent Monotony of the Installation Stage .......... 410 Stability of Mosaics Versus Eco-Unit Fluidity. . . . . . . . .. 411 The Precuilibrium Stage. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 412 Canopy Closure: Layers, Stufung and Schichtung ...... 412 Eco-Unit Composition Throughout the PrecuilibriJ.lm . .. 416 ThePrecuilibrium, Animals and Fungi ................ 419 The Precuilibrium and Silviculture. . . . . . . . . . . . . . . . . . .. 424 The Ecuilibrium Stage .............................. 427 Kaleidoscopic Balance in Eco-Unit Composition. . . . . .. 427 Tree Species and Their Strategies ..................... 428 Succession and Silvigenetic Cycles. . . . . . . . . . . . . . . . . . .. 431

xx

6.2.4.4 6.2.4.5 6.2.4.6 6.2.4.7 6.2.4.8 6.2.4.9 6.2.5 6.2.5.1 6.2.5.2 6.2.5.3 6.2.6 6.2.7 6.2.8 6.2.8.1 6.2.8.2 6.2.8.3 6.2.8.4 6.2.8.5 6.2.8.6 6.2.8.7 6.2.8.8 6.2.8.9 6.3

6.3.1 6.3.2 6.3.3

6.3.4 6.3.5 6.3.6 6.3.7 6.3.8 6.3.8.1 6.3.8.2 6.3.8.3 6.4 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5 6.4.6 6.4.7 6.5 6.5.1

Contents

Large Animals and the Ecuilibrium ................... 436 The Propagule Bank and the Ecuilibrium . . . . . . . . . . . . .. 439 Birds, Propagules and the Ecuilibrium ................ 445 Significance for Nature Conservation and Silviculture. .. 449 Flowering and Fruiting Periodicity: Mast Years ........ 450 The Ecuilibrium Stage: Summary Outline ............. 452 The Elimination Stage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 452 Stress and Eco-Unit Elimination. . . . . . . . . . . . . . . . . . . . .. 452 Long-Lasting Stress: The Ulrich Model. . . . . . . . . . . . . . .. 454 The Elimination Stage: Final Remarks ................ 455 The Stage of Collapse ............................... 455 Rhizospheres in Silvatic Mosaics ..................... 456 Examples of Silvatic Mosaics ........................ 459 The Broadleaved Forests at Fontainebleau, France ..... 460 Pioneer Birch Mosaic, the Netherlands . . . . . . . . . . . . . . .. 464 Neo-Natural Mosaic Fragment, the Netherlands ....... 467 Semi-Natural Mediterranean Silvatic Mosaics ......... 470 Tropical Ecuilibrium Mosaic in the Andes, Ecuado ..... 473 Tropical Floodplain Ecuilibrium Mosaic, Brazil . . . . . . .. 476 Ecuilibrium Mosaic Fragments, Southeast Asia ........ 476 Eco-Unit Interaction in Ecuilibrium, Indonesia ........ 479 Ecuilibrium Mosaic in African Rainforest, Zaire . . . . . . .. 481 The Life Cycle of Silvatic Mosaics: Populations and Succession . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 484 Concepts .......................................... 484 Physiognomic, Descriptive Classifications ............. 485 Physiognomy, Species, Dynamics: The Central European Model ............................................ 485 Successional Models Using Species Composition. . . . . .. 494 Physiognomic Structure and Mosaic Architecture ...... 496 A Shifting Mosaic Matrix: The Torquebiau Calculation . 502 Graphical Succession Models . . . . . . . . . . . . . . . . . . . . . . .. 507 Species Populations, Selection Pressure, Speciation. . . .. 510 A Hierarchical Model of Selection Pressure. . . . . . . . . . . 510 Species Conservation and Human Health Aspects ...... 516 Speciation, Provenances, Tree Breeding ............... 520 The Life Cycle of Silvatic Mosaics: Production Models .. 522 Relation Diagram for a Silvatic Mosaic. . . . . . . . . . . . . . .. 522 Mosaic Production and Average Tree Production. . . . . .. 525 Methods of Compartmentalisation ................... , 528 Transfer of Functions in Silvatic Mosaics .............. 532 Biogeochemical and Hydrological Cycles; Biomas . . . . .. 534 Light and Forest Photology .......................... 543 Site Quality and Productivity ................ ; . . . . . . .. 546 Site Resource Distribution and Silvatic Mosaics ........ 548 Biosphere Models .................................. 549

Contents

6.5.2 6.5.3 6.6

XXI

Models for Large Ecosystems and Landscape Ecology 552 Some Remarks on Altitudinal and Latitudinal Gradients 557 Preliminary Conclusion on Silvatic Mosaics ........... 558

7 Some Important Silvological Rules .................... 559

7.1 WhatAreRules? ................................... 559 7.2 The Rules of Scale .................................. 560 7.3 The Rules of Fragmentation and Fusion. . . . . . . . . . . . . .. 561 7.4 The Rules of Transfer of Functions ................... 562 7.5 The Rules of Irreversibility and Process Oscillation ..... 563 7.6 Use and Significance of These Rules. . . . . . . . . . . . . . . . .. 564

References ................................................. 567

Subject Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 597