Biofilm phosphorus uptake capacity as a tool for the assessment of pollutant effects in river ecosystems.
Ecotoxicology
; 26(2): 271-282, 2017 Mar.
Article
en En
| MEDLINE
| ID: mdl-28108888
ABSTRACT
Biofilms are a key component in the nutrient removal from the water column. However, nutrient uptake by biofilms may be hampered by the occurrence of pollutants or other stressors. This study aimed (i) to investigate the biofilm phosphorus (P) uptake capacity as a relevant process for the maintenance of fluvial water quality and (ii) to explore the sensitivity of this process to different chemical and environmental stressors. We conducted chamber experiments to test for the relevance of biofilm P uptake capacity (PUC) as a tool to detect effects of pollutants on river self-depuration. PUC was calculated by measuring P temporal decay after performing controlled P-spikes in chambers with biofilm-colonized tiles. Four different experiments were conducted to evaluate the response of PUC to (a) several river waters from increasing polluted sites; (b) the effect of the bactericide triclosan (TCS); (c) the combined effect of TCS and grazers; and (d) the effect of TCS after a drought episode that affected the biofilms. These experiments showed that biofilms decreased their PUC along the pollution gradient. The biofilm PUC was significantly reduced after receiving high TCS concentrations, though lower TCS concentrations also affected the biofilm when this was submitted to grazing pressure. PUC decrease was induced by flow interruption which further enhanced the TCS negative effects. Overall, PUC was sensitive to the effects of pollutants like TCS as well as to the action of biological (grazing) and environmental (drought) factors. The study also showed that multiple stressors enhance the negative effects of pollutants on the PUC of biofilms. Our study values the use of biofilms' PUC as a sensitive ecological-based tool to assess the effects of chemicals on freshwater communities and their derived functioning in river ecosystems.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Fósforo
/
Contaminantes Químicos del Agua
/
Monitoreo del Ambiente
/
Biopelículas
/
Fenómenos Fisiológicos Bacterianos
País/Región como asunto:
Europa
Idioma:
En
Revista:
Ecotoxicology
Asunto de la revista:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Año:
2017
Tipo del documento:
Article
País de afiliación:
España