title: In situ determination of the effects of lead and copper on cyanobacterial populations in microcosms.
abstract: BACKGROUND
  Biomass has been studied as biomarker to evaluate the effect of heavy metals on microbial communities. Nevertheless, the most important methodological problem when working with natural and artificial microbial mats is the difficulty to evaluate changes produced on microorganism populations that are found in thicknesses of just a few mm depth.
  
  
  RESULTS
  Here, we applied for first time a recently published new method based on confocal laser scanning microscopy and image-program analysis to determine in situ the effect of Pb and Cu stress in cyanobacterial populations.
  
  
  CONCLUSIONS
  The results showed that both in the microcosm polluted by Cu and by Pb, a drastic reduction in total biomass for cyanobacterial and Microcoleus sp. (the dominant filamentous cyanobacterium in microbial mats) was detected within a week. According to the data presented in this report, this biomass inspection has a main advantage: besides total biomass, diversity, individual biomass of each population and their position can be analysed at microscale level. CLSM-IA could be a good method for analyzing changes in microbial biomass as a response to the addition of heavy metals and also to other kind of pollutants.
authors: Department of Genetics and Microbiology, Biosciences Faculty, Universitat Autònoma de Barcelona, Barcelona, Spain. mireia.burnat@uab.cat
authors: Mireia
authors: M
authors: Burnat
authors: Elia
authors: E
authors: Diestra
authors: Isabel
authors: I
authors: Esteve
authors: Antonio
authors: A
authors: Solé
mesh_terms: D018533:Biomass; D015169:Colony Count, Microbial; D003300:Copper / Q000494:pharmacology*; D000458:Cyanobacteria / Q000187:drug effects* / Q000254:growth & development; D007854:Lead / Q000494:pharmacology*; D018613:Microscopy, Confocal; D014874:Water Pollutants, Chemical / Q000494:pharmacology*
chemical_list: D014874:Water Pollutants, Chemical; D007854:Lead; D003300:Copper