BALTIC SEAENVIRONMENT PROCEEDINGS No. 59 - Helcom

Table 2 (cont'd)
However, these two species are migratory and any sampling of them
must pay due attention to the period when they probably represent
the area where they are caught.
For practical reasons, only species with a relatively large
individual size can be used. Both Macoma and Saduria occur
throughout almost the entire Baltic Sea area, and are chosen as
optinal species in the BMP. In the Baltic, Mytilus edulis
penetrates into deeper waters and is also used as a tentaive
indicator species at a number of stations in the open sea.
It is recommended that the determination of individual
chlorobiphenyl compounds be made obligatory by the end of the
Third Stage, with quantification of the following CBS : IUPAC Nos.
28, 52, 101, 118, 138, 153, 180.
Analytical methods for contaminants such as polychlorinated
camphenes (PCCs, e g toxaphene), dibenzodioxins and -furans
(PCDDs, PCDFs) and PAHs require much work before comparable data
will be obtained. It is important that research continues in order
to develop efficient analytical tools to be used for serial
analyses.
Biological determinands.
Obligatory:
Phytoplankton: primary production, chlorophyll-a, species
composition, biomass.
Zooplankton: species composition, abundance, biomass.
Macrozoobenthos: species composition, abundance, biomass.
Tentative: Phytoplankton phaeopigments, protozooplankton, pelagic
micro-organisms (total number, biomass and production of
bacteria).
Remarks: It is essential that sampling of macrozoobenthos is
accompanied by some hydrographic determinations. Bottom water
should therefore be sampled for the determination of S, T, O,/H,S.
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