Biofilm early stage development in two nutrient‐rich streams with different urban impacts

COCHERO, J.; NICOLOSI GELIS, M.M.; MARÍA BELÉN SATHICQ; GOMEZ N,

RIVER RESEARCH AND APPLICATIONS

JOHN WILEY & SONS LTD

Lugar: LOndres; Año: 2019 vol. 34 p. 755 - 764

1535-1459

The aimof this studywas to describe the colonization of the biofilmduring its early stagesunder different concentrations of nutrients and organic matter, specifically in urbanstreams influenced by agriculture and urbanization. We hypothesized that in a streamwith higher concentrations of nutrients and organic matter, the initial biomass growthwould be faster, and the changes in the structure of the community would be greater.Sterile glass substrates were placed in 2 urban streams that differed in nutrient andorganicmatter concentrations; sampleswere collected during their firstweek of colonizationto measure total biomass, bacterial biomass, chlorophyll a, activity of the electrontransfer system, and the community composition. Results showthat biofilm developmentin both streams beganwithin a fewhours and differed under different conditions of nutrients;in the stream with a better water quality, the colonization dynamics consisted of 2increments of bacterial biomass linked with an increase of algal biomass. In the urbanstream with higher nutrient and organic matter concentrations, biofilm developmentwas slower and consisted of a simultaneous increase of bacteria and algae, consistentwith a lower electron transfer systemactivity. Therefore, the dynamics of the colonizationprocess in addition to those characteristics of the fully developed biofilm could havepotential applications in water monitoring of urban streams.