Intercalibration 9804: Invertebrate fauna (ICP Waters report 47/1998)

Abstract

The 4th intercalibration of invertebrates in the ICP-Water programme had contribution from 6 laboratories. 5 of the laboratories identified a high portion (>85%) of the total number of species in the test samples. Short-coming identification was consequently relatively low. Of the identified species only few falts were made. The results for these laboratories were therefore regarded as good and well within the limit of good identification proposed for intercalibration of biological material. Due to lack of identification literature, one laboratory showed very low identification and also to some extent higher misidentifications both on species and genus level for some invertebrate groups. However, for other groups the laboratory had relevant literature and in these cases the faults were within the limits for what is acceptable. Faults resulting in a wrong acidification index, was not recorded in 1997/98. The results of the biological intercalibration in 1997/98 are the best of all tests performed so far.