Interaction of acid mine drainage with biota in the Allchar Carlin-type As-Tl-Sb-Au deposit, Macedonia

Allchar ore deposit, a well-known polymetallic mineralisation, is drained by the Majdanska River characterized by elevated concentrations of heavy metals and metalloids, particularly As, Tl and Sb. The present study was conducted at the spot of the confluence of spring water, heavily loaded with toxic metals, which joins the Majdanska River by a few meters short stream. The spring water is outflow of underground water drained by passage through polymetallic mineralisation. The chemical characteristics of the Majdanska River water and the associated periphyton were used to evaluate and explain the abiotic response to the intrusion of toxicants and its impact on biota.