Principles of collection and plankton sample handling from ballast tanks to assess the efficiency of ship ballast water treatment systems

Based on the material collected in 2004–2006 and 2009–2010 in the Novorossiysk Sea Port from the ships of the merchant fleet as well as the literature data, the collection and sample handling methods of phyto- and zooplankton from ballast tanks were analyzed. To assess the efficiency of the ballast water treatment systems (BWTS), there should be introduced correct definitions of the number, size and taxa of viable phyto- and zooplankton organisms in the IMO BWM documents. It is recommended to use closed Sorokin-type chambers of different sizes for express analysis (microscopy) of nanoplankton and microplankton on board a ship. To control compliance with the ballast water discharge standard, the mortality ratio of aquatic organisms should be 100% in the decontaminated ballast water. Effective decontamination of ballast water using UV irradiation is not possible unless BWTS is installed on the ballast water flow (draining) from the vessel. It is necessary to develop instructions for carrying out the procedure for obtaning ballast water samples for different types of ships and analyzing them for the facilities under the technical supervision of the Russian Maritime Register of Shipping. The aim of the study is to analyze the basic principles of collecting and sample handling of phyto- and zooplankton from the ballast tanks to control their compliance with the standard for ballast water discharge into the territorial waters of the Russian Federation.