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Denitrification Associated with Stream Periphyton: Chamber Estimates from Undisrupted Communities
Author(s) -
Duff J. H.,
Triska F. J.,
Oremland R. S.
Publication year - 1984
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq1984.00472425001300040002x
Subject(s) - periphyton , denitrification , nitrous oxide , environmental chemistry , denitrifying bacteria , chemistry , nutrient , nitrification , nitrogen , organic chemistry
Undisrupted periphyton communities from a N‐rich (NO 3 − = 63 µ mol L −1 ) and pristine (NO 3 − = 2.9 µ mol L −1 ) stream were assayed for denitrifying activity (acetylene‐blockage technique) in 40‐L chambers incubated at in situ temperature and nutrient concentrations. Nitrous oxide formation associated with periphyton from the N‐rich stream was immediate and linear (52.1 µ mol N 2 O m −2 h −1 ) in the dark, anaerobic chamber (50 kPa C 2 H 2 ). In the corresponding light, aerobic chamber (50 kPa C 2 H 2 ), N 2 O production was inhibited by 82% (9.3 µ mol N 2 O m −2 h −1 ). Nitrous oxide formation was not associated with periphyton from the pristine stream incubated in situ, either with or without NO 3 − amendment. Denitrification estimates made with undisrupted periphyton communities at in situ temperature and nutrient concentrations (40‐L chambers) were less variable than estimates made with periphyton “scrapings” in small flasks (room temperature). The calculated diel periphyton‐associated denitrification rate based on a 14‐h light‐10‐h dark day was 651 µ mol N 2 O m −2 d −1 . The data suggest denitrification within periphyton mats may contribute toward removal of NO 3 − from N‐rich fluvial environments.