en
Scientific article
English

Porous Underwater Chamber (PUC) for in-situ determination of nutrient and pollutant bioavailability to microorganisms

Published inLimnology and oceanography, methods, vol. 6, p. 277-287
Publication date2008
Abstract

Physical (e.g., temperature and light) and biogeochemical (e.g., cycling) parameters are known to affect bioavailability and toxicity of nutrients and pollutants to microorganisms. A system that would allow exposure of selected microorganisms to in situ conditions could provide relevant and novel evaluations of bioavailability. A simple and low cost 37 mL porous underwater chamber (PUC), in which test microorganisms are exposed to field conditions, is presented. The PUC is a thin, acrylic cylinder with polycarbonate membranes on each side, providing an optimal (75 cm2) exchange with the external solution. Regardless of the membrane pore size (0.4 and 5 µm), the PUC required 10 h to equilibrate with the external solution, close to the theoretical time determined for the diffusion of a model compound, the Suwannee River fulvic acid. For in situ use, the PUCs can be filled with filtered water to minimize the equilibration time. The system was validated in 20 to 60 L artificial freshwater by evaluating (1) Cd bioaccumulation by the microalga Chlamydomonas reinhardtii and (2) iron bioavailability to a cyanobacterial bioreporter in comparison with conventional bottle assays. The use of the PUC resulted in no significant differences in Cd uptake fluxes or iron bioavailability. Field experiments undertaken on Lake Erie demonstrated that the PUCs could be used to evaluate the contribution of particulate iron to iron bioavailability. Because the PUCs might not correctly reflect bioavailability for substances at low concentrations with high biouptake fluxes, a critical discussion with respect on the rate-limiting steps of the device is presented. Several considerations that might facilitate the appropriate use of the PUCs are given.

Affiliation Not a UNIGE publication
Citation (ISO format)
HASSLER, Christel et al. Porous Underwater Chamber (PUC) for in-situ determination of nutrient and pollutant bioavailability to microorganisms. In: Limnology and oceanography, methods, 2008, vol. 6, p. 277–287. doi: 10.4319/lom.2008.6.277
Main files (1)
Article (Published version)
accessLevelRestricted
Identifiers
ISSN of the journal1541-5856
565views
4downloads

Technical informations

Creation02/10/2013 9:46:00 AM
First validation02/10/2013 9:46:00 AM
Update time03/14/2023 8:03:08 PM
Status update03/14/2023 8:03:07 PM
Last indexation01/16/2024 1:13:07 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack