Ecological state of North -Western Black Sea macrobenthos on offshore bottoms deeper than 50 m

In the last 10-15 years researches concerning benthos in the north-western Black Sea were focused mainly on inshore bottoms, usually less than 50 m deep, where important ecological changed occurred. The offshore bottoms, deeper than 50 m, and especially the periazoic level at the edge of the continental shelf have been less known, the information being scarce. The present study gathers the results of the researches carried out in the past 12 years on the Modiolus phaseolinus community, including the periazoic level, and allows a comparison to be drawn with the situation of the so-called “ecological stability” period at the beginning of the 1960s, before the ecosystemic disturbances began in the Black Sea. In 1995-2007, a number of 133 quantitative macro-benthos samples were collected at depths of 50 – 213 m by means of the van Veen-type grab and box corer; these samples were taken during several cruises (R/V “Prof.Vodyanitskyi” EROS 1995, 1997, R/V „Akademik” 2003, R/V „Parshin” 2005, R/V „Akademik” 2006 R/V „Mare Nigrum” 2006 and 2007), the researches aiming at the assessment of the benthic ecosystem state.