Processes within pasture and crop ecosystems: The study of ecosystems

[First paragraphs...]
The term "ecosystem" may be defined as "an open system comprising plants, animals, organic residues, atmospheric gases, water and minerals which are involved together in the flow of energy and the circulation of matter".
It is an all-embracing system and this gives it its greatest value-that it is treated as a whole, not as a number of separate parts.
As papers on soils, papers on climate and others on plants and animals, even if they penetrate some way into neighbouring fields, do not add up to a symposium on ecosystems I thought I would resist the inclination to discuss soils and nutrient cycling, and instead deal more generally with the study of ecosystems. This might provide a wider perspective and encourage discussion to range more freely.