Open AccessThe adaptation of nitrate‐reducing bacterial communities in estuarine sediments in response to overlying nitrate load
Author(s) -
King D.,
Nedwell D.B.
Publication year - 1987
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1987.tb02333.x
Subject(s) - nitrate , environmental chemistry , estuary , effluent , sediment , environmental science , ammonium , nitrite , chemistry , environmental engineering , ecology , geology , biology , paleontology , organic chemistry
Examination of the nitrate and ammonium concentrations at 10 stations in the estuary of the River Colne, Essex, UK, revealed the presence of a pollution gradient within the estuary. The greatest concentrations of nitrate, both in the water and within the sediment, were measured near the outfall of a sewage works from which well‐nitrified effluent was discharged. Measurements of the rate of nitrate reduction at each site, incubated at constant temperature and constant initial nitrate concentration, showed adaptation of the sediment bacterial communities, with those sediments having greater nitrate concentrations exhibiting faster rates of nitrate reduction. In addition, the proportion of nitrate reduced to gaseous products (denitrified), rather than to nitrate or ammonium, also increased with the nitrate concentration. These changes were interpreted as being the result of adaptation of the in situ sedimentary bacterial nitrate‐reducing communities in response to the ambient concentrations of nitrate at each station.