Le 16 octobre 2018 (amphi ISTE), FengFeng Zhang, doctorante à l'ISTO encadrée par Fabienne Bataglia et Mikaël Motelica-Heino, nous propose un séminaire intitulé "Arsenic linked to a former mining activity in the Hunan province: distribution at the local scale and bacterial AsIII oxidation".
The impact of a former small Pb-Zn mine in Hunan (China) was studied in terms of arsenic and metals concentrations in water streams and sediments, and from the perspective of biogeochemistry of arsenic. Three water streams were characterized, two from galleries and one seeping at the base of the mine waste rocks dump. Contrary to the water from galleries, this last stream was acidic and contained relatively high arsenic concentration. High arsenic levels were also found in sediments downstream of the mine drainage flowing from the first gallery. Diverse AsIII-oxidizing bacteria were enriched and isolated from the mine sediments, some presenting ability to grow at low pH or in autotrophic conditions.