dc.contributor |
Universitat de Barcelona |
dc.contributor.author |
Bernal Berenguer, Susana |
dc.contributor.author |
Segarra, Anna |
dc.contributor.author |
Merbt, Stephanie N.. |
dc.contributor.author |
Martí, Eugènia |
dc.date |
2019-03-13T18:53:01Z |
dc.date |
2019-03-13T18:53:01Z |
dc.date |
2017-10-17 |
dc.date |
2019-03-13T18:53:01Z |
dc.identifier.citation |
2161-9549 |
dc.identifier.citation |
677469 |
dc.identifier.uri |
http://hdl.handle.net/2445/130299 |
dc.format |
10 p. |
dc.format |
application/pdf |
dc.language.iso |
eng |
dc.publisher |
The University of Chicago Press |
dc.relation |
Reproducció del document publicat a: https://doi.org/10.1086/696267 |
dc.relation |
Freshwater Science, 2017, vol. 37, num. 1, p. 13-22 |
dc.relation |
https://doi.org/10.1086/696267 |
dc.rights |
(c) The Society for Freshwater Science, 2017 |
dc.rights |
info:eu-repo/semantics/openAccess |
dc.subject |
Biofilms |
dc.subject |
Plantes |
dc.subject |
Nitrogen |
dc.subject |
Biofilms |
dc.subject |
Plants |
dc.subject |
Nitrogen |
dc.title |
Differences in ammonium oxidizer abundance and N uptake capacity between epilithic and epipsammic biofilms in an urban stream |
dc.type |
info:eu-repo/semantics/article |
dc.type |
info:eu-repo/semantics/publishedVersion |
dc.description.abstract |
The capacity of stream biofilms to transform and assimilate N in highly N-loaded streams is essential to guarantee the water quality of freshwater resources in urbanized areas. However, the degree of N saturation experienced by urban streams and their response to acute increases in N concentration are largely unknown. We measured changes in the rates of NH4+ uptake (UNH4) and oxidation (UAO) resulting from experimental increases in NH4+-N concentration in mature biofilms growing downstream of a wastewater treatment plant (WWTP) and, thus, naturally exposed to high N concentration. We investigated the responses of UNH4 and UAO to NH4+-N increases and the abundance of NH4+ oxidizing bacteria and archaea (AOB and AOA) in epilithic and epipsammic biofilms. UNH4 and UAO increased with increasing NH4+-N concentration for the 2 biofilm types, suggesting no N saturation under ambient levels of NH4+-N. Thus, these biofilms can contribute to mitigating N excesses and the variability of NH4+-N concentrations from WWTP effluent inputs. The 2 biofilm types exhibited different Michaelis-Menten kinetics, indicating different capacity to respond to acute increases in NH4+-N concentration. Mean UNH4 and UAO were 5× higher in epilithic than epipsammic biofilms, coinciding with a higher abundance of AOA+AOB in the former than in the later (76 × 104 vs 14 × 104 copies/cm2). AOB derived from active sludge dominated in epilithic biofilms, so our results suggest that WWTP effluents can strongly influence in-stream NH4+ processing rates by increasing N inputs and by supplying AOA+AOB that are able to colonize some stream habitats |