On variation, uncertainty and informatics in environmental soil management

The soil scientist's duty in the debate on environmental management is, at least, to understand the soil and to provide and purvey accurate and precise information concerning it. This paper deals with information m environmental soil management; especially the way its quality and quantity may be modified by soil variation and various kinds of uncertainty, and how its presentation may be enhanced by the accoutrements of information technology. Soil exhibits continuous change m space and time. This variation is usually considered to be problematic in relation to sampling effort, quality of information and for optimal soil management. When ecological principles are considered soil variation is seen as a risk-averse strategy and may be advantageous for sustainable management. Evidence from cultivation is presented to support this hypothesis. The concept of pedodiversity is discussed and a simple example of an optimal preservation strategy based on pedodiversity is given. Three types of uncertainty in soil information are considered in detail: stochastic, deterministic and semantic. The tools of informatics which allow the soil scientist to provide more information or more detailed information for the same effort are discussed briefly These are knowledge-based systems, simulation modelling, spatial and temporal statistics and geostatistics, multivariate techniques, aspatial and spatial information systems. Combinations of these techniques are particularly powerful. Environmental soil management requires a philosophy that generates ways of thinking about soil from which flows realistic soil data models. Such models can be manipulated by the tools of informatics which are not to be considered as ends in themselves.