18 - The future of soil research

Summary

A rather pragmatic view of soil is adopted in this final chapter which is based on three broad categories of land use/function: soil that is (a) managed for production (food, fibre or energy) purposes, (b) either used directly by humans (urban, recreation and transport) or provides necessary raw materials, (c) not directly managed for human purposes. The first two categories when combined represent more than half the available global land resource. The overwhelming significance and impact of anthropogenically related factors on the properties of atmosphere, biosphere, hydrosphere and pedosphere are becoming increasingly evident. The increased exploitation and utilization of soil with time has seen a change in the geographical scale over which impacts have become detectable. While local and geographically isolated issues of environmental degradation have occurred throughout recent history (see Hutchison, 1970, who describes the early influences of a Roman road, Via Cassia, on sediment delivery and subsequent eutrophication) there is increasing evidence of regional and global scale impacts. It has been well argued that probably none of the Earth's ecosystems remains in a ‘pristine’ condition. This situation is most easily demonstrated using the example of the nitrogen cycle and aspects of this relevant to soil are described later. Conventional ecosystem level description of nutrient cycles now require an upscaling component that includes the transport of food products from rural to urban areas of high population densities and movement of livestock and human waste products.