Open AccessPotential rates and pathways of microbial nitrate reduction in coastal sediments
Author(s) -
Laverman Anniet M.,
Van Cappellen Philippe,
Van RotterdamLos Debby,
Pallud Céline,
Abell Jeffrey
Publication year - 2006
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2006.00155.x
Subject(s) - nitrate , biogeochemical cycle , eutrophication , environmental chemistry , sediment , ammonium , biology , denitrification , ecology , nitrogen , nutrient , chemistry , paleontology , organic chemistry
Nitrate reduction plays a key role in the biogeochemical dynamics and microbial ecology of coastal sediments. Potential rates of nitrate reduction were measured on undisturbed sediment slices from two eutrophic coastal environments using flow‐through reactors (FTR). Maximum potential nitrate reduction rates ranged over an order of magnitude, with values of up to 933 nmol cm −3 h −1 , whereas affinity constants for NO 3 − fell mostly between 200 and 600 μM. Homogenized sediment slurries systematically yielded higher rates of nitrate reduction than the FTR experiments. Dentrification was the major nitrate removal pathway in the sediments, although excess ammonium production indicated a contribution of dissimilatory nitrate reduction to ammonium under nitrate‐limiting conditions.