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Self-Organising Agro- Ecosystems Self-organising Agro- ecosystems by Raoul A. Robinson Second edition, revised Sharebooks Publishing www.sharebooks.ca - 1 - © Raoul A. Robinson, 1996, 2004, 2007. Permission to Reproduce. Any person, library, or organisation may download, print, photocopy or otherwise reproduce this book for purposes of private study, and do so free of legal or financial liability. However, this book is copyrighted and may not be reproduced in any form for purposes of financial gain without prior permission in writing from the publisher, except by a reviewer who wishes to quote brief passages in connection with a review for inclusion in a journal, magazine, or newspaper. If a copy of this book is given free of charge to a third person then it must contain this copyright notice in full. This book is also available as shareware: anyone may download it, and may make an entirely voluntary contribution, by way of compensation to the author and publisher, via www.sharebooks.ca on the internet. Library and Archives Canada Cataloguing in Publication Robinson, Raoul A. Self-organising agro-ecosystems / by Raoul A. Robinson. -- 2nd ed., rev. Also available in electronic format. Includes bibliographical references. ISBN 978-0-9783634-1-3 1. Agricultural ecology. I. Title. S589.7.R63 2007 577.5'5 C2007-905616-4 - 2 - Preface This work proposes methods of reducing, even eliminating, the use of crop protection chemicals from our crops and environment. It seems that this can best be achieved by self-organisation ( sensu Adam Smith) within agro-ecosystems. This self-organisation can be brought about by numerous plant breeding clubs that are employing durable resistance to crop parasites. If we consider the food production of a country, we find a self-organising system. Many farmers, acting individually, choose what crops to grow, and what cultivars of those crops to grow. Their decisions are based mainly on their environment, and on market demand, which comes from the decisions of individual merchants who buy their produce. Systems of transport and food processing convert raw materials into marketable products, and retailers make these products available to consumers through stores and super-markets. These consumers choose what they buy, usually on a basis of either cost or quality. The stores must stock items according to customer preferences. There must be some government control to ensure purity and hygiene, and to prevent monopolies and cornered markets. But, in general, too much government control is damaging. This was revealed dramatically by the failure of the Soviet system of State-controlled agriculture. Government control must be kept to the essential minimum, and the entire system should be self-organising. The importance of this phenomenon of self-organisation was first recognised by Adam Smith (1723-1790) in his book The Wealth of Nations , published in 1776, although he did not use this term. Immanuel Kant (1724-1804) was apparently the first to use the term ‘self-organisation’. The present volume is intended primarily for - 3 - universities wishing to initiate student clubs for plant breeding, but it may also be of interest to any scientist involved with crop parasites. A proper understanding of this topic requires an acquaintance with the general systems theory, modern complexity theory and, most of all, various concepts of the ecosystem and the pathosystem. A further purpose of the present book is to summarise, bring up to date, and present in one volume, concepts that I consider relevant in earlier writings of mine, including books that are now out of print. - 4 - Chapter One 1. General Systems Theory 1.1 Introduction The founder of systems theory was a little known Russian scientist called Alexander Bogdanov, who published a three-volume work entitled Tektology in 1912-1917. A German edition was published in 1928 but the work remained largely unrecognised and unknown in the West. Lenin denounced Bogdanov on ideological grounds, and the Soviet authorities suppressed his works. About a quarter of a century later, an Austrian scientist, Ludwig von Bertalanffy, developed his general systems theory. It is unlikely that he was ignorant of Bogdanov’s earlier work, but he never acknowledged it, and the lingering possibility of plagiarism cannot be entirely dispelled. Nevertheless, Bertalanffy was very influential, and he is widely recognised as one of the principle founders of the general systems theory. His main contribution was the concept of the open system, which would allow energy to flow into it and, interestingly, this was an enlargement of the second law of thermodynamics. The French physicist Sadi Carnot first formulated the second law of thermodynamics, which postulates that all energy gradients disappear in a closed system. This process is described as an increase in entropy, or disorder. A closed system will thus tend to total internal uniformity of energy distribution. The open system is in direct contrast and, by absorbing energy from outside, it can increase its energy gradients. An open system can be described by saying that its negative entropy (negentropy) increases. - 5 - The concept of negative entropy can be applied to complexity of organisation, as well as to energy. In a closed system, organisation tends to disappear, resulting in total disorganisation, and simplicity of arrangement. In an open system, organisation tends to increase, resulting in complexity of organisation. All living systems are open systems. They absorb energy, and their complexity of organisation increases. 1.2 Patterns A pattern is an arrangement of units. A wall is a pattern of bricks, a word is a pattern of letters, a tune is a pattern of notes, a molecule is a pattern of atoms, and so on. 1.3 Systems A system is a series of patterns of patterns, and each pattern of patterns is called a systems level (see 1.4) . There are many kinds of system, including electrical systems, mechanical systems, political systems, solar systems, living systems, taxonomic systems, traffic systems, and so on. Systems theory studies the properties that these various systems have in common. The most relevant of these properties are described under the various headings below. When it is applied to a word, the suffix ‘ -ation ’ often implies a system. Thus, we have ‘transport’ and ‘transportation’. When someone offers a ride and says “May I offer you transportation?” he should really say ‘transport’. And the system of public busses and underground trains in London is called “London Transport”, when it should really be “London Transportation”. Similar comments can be made about ornament and ornamentation (a system of ornaments), classification (a system of classes), experimentation, hyphenation, organisation, plantation, medication, and so on. - 6 - 1.4 Systems Levels A pattern of patterns is usually called a systems level. For example, a book is a static system, which consists of subsystems called chapters. Collectively, these chapters constitute a systems level. Each chapter consists of subordinate patterns of patterns (or secondary subsystems) called paragraphs. And so on, downwards, through sentences, words, and letters. The book itself is part of a super-system called a library. Clearly, a book has many systems levels. The importance of recognising systems levels is that they lead to the concepts of emergents, reductionism, and suboptimisation. It will transpire that these concepts are central to any analysis of twentieth century crop science. 1.5 Hierarchies and Networks We tend to think of systems levels in terms of hierarchies. Each systems level is a rank in the hierarchy, superior to the rank below it, and inferior to the rank above it. This is a very convenient and useful method of analysis but, in fact, it is often a misrepresentation. It is perhaps more accurate to think in terms of networks, and of networks nesting within other networks, all interacting within themselves and among themselves. Some networks are larger than others, but this does not necessarily make them superior. Nevertheless, for simplicity of discussion, I will continue writing in terms of systems levels. A beautiful example of a network is the Internet. Here is a network of networks if ever there was one. Perhaps we should think of the Internet as some kind of ‘super-organism’, with a ‘life’ of its own, and soon to produce entirely new emergents (see 1.9) of enormous importance, which we can now perceive only dimly, if at all. One of the more obvious emergents will be entirely new forms of global awareness and democracy. - 7 - 1.6 Homeostasis The term ‘homeostasis’ was coined by the American physiologist Walter Cannon (1932) who was describing the many self-regulatory mechanisms in the human body. The classic example of homeostasis is the maintenance of body temperature. If we get too hot, we sweat, and evaporation cools us down. Conversely, if we get too cold, we start shivering, and this involuntary exercise warms us up. Subsequently, homeostasis was recognised in many other systems. For example, Lerner (1954), coined the term ‘genetic homeostasis’ to describe the maintenance of an optimum genetic constitution of a population. Homeostasis describes an important aspect of systems control, which results in the maintenance of a desirable steady state. The mechanism of this control is called feedback. 1.7 Feedback The term ‘feedback’ refers to the output controlling or influencing the input. The cyberneticists, who recognised two kinds of feedback, introduced the concept of the ‘feedback loop’. And they called self-balancing feedback ‘negative feedback’, and self-reinforcing feedback ‘positive feedback’. Negative feedback is illustrated by all homeostatic mechanisms. For example, the automatic steering of a ship exhibits a phenomenon that engineers call ‘hunting’. That is, the ship tends to veer slightly away from its proper course, and the homeostatic steering mechanism brings it back again. But it may then veer slightly off course in the other direction, and the steering mechanism brings it back again.
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