2006
O’Connor, B. L.; Hondzo, M.; Dobraca, D.; LaPara, T. M.; Finlay, J. C.; Brezonik, P. L.
Quantity-activity relationship of denitrifying bacteria and environmental scaling in streams of a forested watershed Journal Article
In: Journal of Geophysical Research, vol. 111, no. G4, pp. 1-13, 2006.
Abstract | Links | BibTeX | Tags: denitrifying bacteria, environmental scaling, forested watershed
@article{O'Connor2006,
title = {Quantity-activity relationship of denitrifying bacteria and environmental scaling in streams of a forested watershed},
author = {B. L. O'Connor and M. Hondzo and D. Dobraca and T. M. LaPara and J. C. Finlay and P. L. Brezonik},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/OConnor_2006_JourGeophysRes.pdf},
doi = {10.1029/2006JG000254},
year = {2006},
date = {2006-11-30},
journal = {Journal of Geophysical Research},
volume = {111},
number = {G4},
pages = {1-13},
abstract = {The spatial variability of subreach denitrification rates in streams was evaluated with respect to controlling environmental conditions, molecular examination of denitrifying bacteria, and dimensional analysis. Denitrification activities ranged from 0 and 800 ng-N gsed−1 d−1 with large variations observed within short distances (<50 m) along stream reaches. A log-normal probability distribution described the range in denitrification activities and was used to define low (16% of the probability distribution), medium (68%), and high (16%) denitrification potential groups. Denitrifying bacteria were quantified using a competitive polymerase chain reaction (cPCR) technique that amplified the nirK gene that encodes for nitrite reductase. Results showed a range of nirK quantities from 103 to 107 gene-copy-number gsed−1. A nonparametric statistical test showed no significant difference in nirK quantities among stream reaches, but revealed that samples with a high denitrification potential had significantly higher nirK quantities. Denitrification activity was positively correlated with nirK quantities with scatter in the data that can be attributed to varying environmental conditions along stream reaches. Dimensional analysis was used to evaluate denitrification activities according to environmental variables that describe fluid-flow properties, nitrate and organic material quantities, and dissolved oxygen flux. Buckingham's pi theorem was used to generate dimensionless groupings and field data were used to determine scaling parameters. The resulting expressions between dimensionless NO3− flux and dimensionless groupings of environmental variables showed consistent scaling, which indicates that the subreach variability in denitrification rates can be predicted by the controlling physical, chemical, and microbiological conditions.},
keywords = {denitrifying bacteria, environmental scaling, forested watershed},
pubstate = {published},
tppubtype = {article}
}
The spatial variability of subreach denitrification rates in streams was evaluated with respect to controlling environmental conditions, molecular examination of denitrifying bacteria, and dimensional analysis. Denitrification activities ranged from 0 and 800 ng-N gsed−1 d−1 with large variations observed within short distances (<50 m) along stream reaches. A log-normal probability distribution described the range in denitrification activities and was used to define low (16% of the probability distribution), medium (68%), and high (16%) denitrification potential groups. Denitrifying bacteria were quantified using a competitive polymerase chain reaction (cPCR) technique that amplified the nirK gene that encodes for nitrite reductase. Results showed a range of nirK quantities from 103 to 107 gene-copy-number gsed−1. A nonparametric statistical test showed no significant difference in nirK quantities among stream reaches, but revealed that samples with a high denitrification potential had significantly higher nirK quantities. Denitrification activity was positively correlated with nirK quantities with scatter in the data that can be attributed to varying environmental conditions along stream reaches. Dimensional analysis was used to evaluate denitrification activities according to environmental variables that describe fluid-flow properties, nitrate and organic material quantities, and dissolved oxygen flux. Buckingham’s pi theorem was used to generate dimensionless groupings and field data were used to determine scaling parameters. The resulting expressions between dimensionless NO3− flux and dimensionless groupings of environmental variables showed consistent scaling, which indicates that the subreach variability in denitrification rates can be predicted by the controlling physical, chemical, and microbiological conditions.