THE Black Sea is the world's largest anoxic basin; it is also a contemporary analogue of the
environment in which carbonaceous shales and petroleum source beds formed1. Recently …

RECENT studies1–8 have documented significant short-term vertical fluctuations in the
position of the oxic–anoxic interface (chemocline) in the waters of the Black Sea, the world's …

THE contribution of anoxygenic photosynthesis to carbon cycling in the Black Sea, the
world's largest body of anoxic marine water, has been vigorously investigated and debated …

LIMITED understanding of the influence of the environment on the relation between
photosynthesis and light in the ocean impairs our capacity to estimate primary production …

THE Black Sea is the largest anoxic marine basin in the world today1. Below the layer of
oxygenated surface water, hydrogen sulphide builds up to concentrations as high as 425 μM …

THE Black Sea, the world's largest anoxic marine basin, is frequently used as a modern
analogue for the formation of organic-rich sediments and carbonaceous rocks1–3, on the …

A KNOWLEDGE of past changes in the biological productivity of the oceans is important for
understanding the interactions between carbon cycling and climate. Phytoplankton …

DURING the past two decades, catastrophic changes have occurred in the Black Sea
ecosystem: the influx of pollution from the major rivers has caused intense eutrophication at …

Cyanophytes range from at least 2,200 Myr (ref. 1) to the Recent, but they only produced
common marine shelly fossils during the Palaeozoic and Mesozoic (570–80 Myr)(Fig. 1) …

Considerable debate exists concerning the magnitude of oceanic primary production, its rate
of transfer to other trophic levels and turnover times of carbon and nitrogen1–5. In nitrogen …