title: Abrupt transition of the northwestern Black Sea shelf ecosystem from a eutrophic to an alternative pristine state
abstract: Long-term (1960-2005) ecological data were used to identify a regime shift in the northwestern Black Sea shelf and to assess whether it has recovered from its former eutrophic state. Following the collapse of fish stocks and the population explosion of the ctenophore Mnemiopsis leidyi between 1988 and 1991, anthropogenic P-PO4 loads from the River Danube dropped strongly in 1992-1993. This decline in P-PO4 levels was caused by reductions in fertilizer use and emissions from land-based point sour
journal: Marine Ecology Progress Series