Rechnergestützte Identifikation von Böden - OPUS Bayreuth ...

Summary
The German national soil ordering system is termed the German Soil Systematics (GSS). The
principle advantage of the system is its innate ability to describe each soil’s morphology and
genesis in a precise and comprehensible manner. Problems nevertheless occur during the practical
application of the GSS. These problems are associated with the allocation of individual
soils into the existing soil ordering system. A clarification of the problem is apparent among
the varying interpretations of the soil morphology by different soil scientists. The systematic
information lacks objectivity and thus reproducibility. As a result the rich systematic content is
insufficiently realized and often inapplicable in continuative problems such as the deduction of
pedotransfer functions.
The main reason behind the problem is termed ’functional overloading’. This term indicates the
GSS’s inability to adequately fulfill both scientific and practical needs (extensive description of
soils and their interrelationships conflicting with the necessity of fast and objective soil identifications).
Nevertheless, the GSS may be optimized for only one of the two goals. The soil
ordering systems ’systematics’ and ’classification’ criteria are distinguished in detail in order to
adequately describe the conflict and to present possible long term solutions.
The soil identification (allocation of soils into the ordering system) requires the categorizing
characteristics to be measured. This process is nearly impossible for systematic information
since the pedogenetic processes are seldom measurable with current technologies. This difficulty
is the main cause for hypothetical soil identifications with the GSS. Solving the identification
problem would become possible by the quantification of pedogenetic processes (proofing the
soil systematics) or by developing a classification from the systematics. The first strategy would
require extensive long term research activity. The only viable short term solution is through the
development of a graded classification system. Three approaches are analyzed for the latter:
• The first determines whether the GSS definitions may be structured through the development
of identification keys for soil horizons and for soil subtypes.
• The second applies a fuzzy cluster/discriminate analysis for the statistical investigation of
soil data.
• The third involves a fuzzy rule based system combining measurement data with verbal
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