Open AccessMineralization budgets in sediment microcosms: Effect of the infauna and anoxic conditions
Author(s) -
Hansen Lars Stenvang,
Blackburn Thomas Henry
Publication year - 1992
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.1574-6968.1992.tb05793.x
Subject(s) - microcosm , mineralization (soil science) , anoxic waters , environmental chemistry , sediment , bioturbation , chemistry , organic matter , nitrogen cycle , nox , nitrogen , water column , oceanography , geology , geomorphology , organic chemistry , combustion
A number of sediment incubations were set up to reproduce some of the conditions used by Kristensen and Blackburn [1] and to make a comparison with their results. There were three types of microcosm: aerobic (OX), anaerobic (AN) and aerobic with Nephtys (NOX). In addition to other measurements, dissolved organic nitrogen (DON) pools and fluxes, were measured. The sediment in this experiment contained more particulate organic matter (POM). Nephtys (NOX) had the same effect as Nereis in increasing the rate of mineralization of POC and PON, compared with the OX‐cores (2.1 and 2.6 times, respectively). Again, the AN‐cores had a higher mineralization rate (loss of POM) than that of the OX‐cores, but in addition, mineralization in NOX‐cores was not significantly different from AN‐cores. It was thus confirmed that anoxic mineralization could be as high, or higher, than the oxic process. Both the temporal patterns of O 2 ‐and and CO 2 ‐fluxes and their magnitudes were very similar to those reported earlier. This contrasts with the higher loss of POM in the present experiment. However, the loss of C in DOC (associated with the measured DON) can account for the extra POM loss. The pore‐water profiles of σCO 2 and NH 4 + were similar to those in the earlier report, and the fluxes of σCO 2 , O 2 , NH 4 + and NO 3 − followed the same temporal pattern.