| Abstract: | Another Revision of the Saprobic Index ‐ Why and What For? The 1990 revision of the German standard DIN 38410 “Determination of the Saprobic Index in Running Waters” had to be revised again in the course of a periodical updating due to the DIN regulations. Thus, practical experience can be taken into account as well as scientific development and the legal requirements. In this work, modifications of the standard are explained as far as it is not done within DIN 38410. Additionally, emerged suggestions and critiques are discussed. The necessity of quality assurance is especially emphasized. An essential part of the revision is the considerable enlargement of the list of indicators (macro‐ and microorganisms). Beside this, type‐specific ranges of the saprobic index are presented for the reference status in all types of German rivers. Consequently the saprobic system may be used as a metric for the biological assessment with the benthic fauna within the implementation of the European Water Framework Directive. Moreover, many details of the standard have been tightened up. The methods for further enlargements of these lists will also be described, especially the proceeding for the inclusion of neozoic organisms as indicators within the saprobic system. A formula concerning the statistical securing of the saprobic index is not given anymore, mainly because of the high variability of habitats and biocoenses in pristine environments. Further information for quality assurance is given as well. |
