Beschreibung:
<jats:p>Shipboard measurements of denitrification were made in sediment from the eastern equatorial Atlantic using an acetylene inhibition technique. Undisturbed subcores were incubated for 1–9 days at 4°C in a N<jats:sub>2</jats:sub>:C<jats:sub>2</jats:sub>H<jats:sub>2</jats:sub> atmosphere (9:1 mixture by volume, 1 atm) and denitrification rates were determined from the observed accumulation of N<jats:sub>2</jats:sub>O. In contrast to the predictions of several recent diagenetic models, no denitrification activity was observed in the region directly beneath the nitrate maximum. However, activity was concentrated lower in the sediment at a depth coincident with an organic‐rich layer.</jats:p>