Introduction

The aim of this document is to identify and describe the current agricultural production systems on the basis of their backgrounds, philosophies and practices. It is relatively straightforward to identify and document the selected systems and describe them, what is a greater challenge is to understand their backgrounds, philosophies and assumptions. For example, Bio-dynamics was developed as a direct response to the failure of previously sustainable farming systems.

In order to gain a better understanding of the transitional development of the current systems, it is necessary to consider the evolution of agriculture and the emergence of the modern systems that are so essential to modern sedentary civilisation. Hence, this document is split into two inter-related parts, firstly an abridged history of agriculture is given, which acts as a foundation in order to appreciate the philosophies and backgrounds of current systems, particularly pre-existing 'organic' agriculture, and secondly the development of the 'conventional' and the 'alternative' schools of thought and their respective production systems. Agricultural history is integral to the understanding of current systems as these systems have evolved from past philosophies or practices or both. Further a lack of knowledge of the past places a limit on our vision and outlook to the future [Serle, 1982]. Judgement on the sustainability of current agricultural systems is greatly influenced by past perceptions. For example there is evidence to indicate that sustainable agricultural systems have existed, although often such ancient systems were often relatively small and isolated and in volcanically active areas and major river deltas that flooded [Reeve, 1990]. These systems often relied on geological processes to provide a supply of nutrients on a continuing cycle. Another well documented example of past sustainable agricultural systems is the oriental 'organic' village agriculture of China and Japan, which has prospered for over four thousand years by recycling all forms of organic matter [King, 1926]. However, there is overriding historical evidence to suggest that most large agricultural systems have failed to support significant urban populations, with the exception of the Nile Valley [Carter, Dale, 1974]. The relevance of this information is increasingly apparent in view of the modern trend of expanding urban civilisations [Reeve, Black, 1993]. The affect of these trends has placed increasing pressure on both the economic sustainability and ecological sustainability [Zarsky, 1990] of current modern systems and further justifies a questioning of their sustainability [Carter, Dale, 1974]. Documenting failures of the past may influence farmers in the importance of assessing the current sustainability of their agricultural production systems, otherwise "those who cannot remember the past are condemned to repeat it - Santayana" [Salmon, Hanson, 1964, p.1].

The second part of this document deals more with the question of what are the current production systems? This question is dealt with by identifying the two opposing paradigms of conventional and alternative agriculture and their respective schools of thought, which are influenced by their theoretical assumptions and underlying techniques. Hence, it is imperative to understand and appreciate the assumptions of each approach, because if they are not identified and remain 'hidden', it is not possible to understand the rationale of these schools of thought or the individuals that participate in them [Whittington, 1994]. Following on from this discussion the term 'agricultural production systems' is defined and explained, which involves a hierarchy of sustainability. Farmers and other interested parties, are increasingly searching for ways to improve or maintain sustainability of agricultural systems [Campbell, 1991], therefore the identification and understanding of these systems is imperative. This raises the question as to how farmers can improve the sustainability of their production system, if they do not understand it, nor have the ability to appraise the sustainability of a such a system. Therefore it is essential to identify specific agricultural production systems. To give balance to this heavily theoretical dissertation a pragmatic view of each system is also taken. This is achieved by integrating several relevant examples of specific management practices that relate to each production system.