Microfungi in highly copper-contaminated soils from an abandoned Fe-Cu sulphide mine: growth responses, tolerance and bioaccumulation

Abstract

Copper is one of the most dangerous soil contaminants. Soils affected by high copper concentrations show low biodiversity and, above all, inadequate environmental quality. Microorganisms such as fungi can play a key role in metal-polluted ecosystems via colonization and decontamination. The study is devoted to characterize the microfungal community in highly Cu-contaminated bare soil from derelict Fe-Cu sulphide mines and to isolate microfungal strains able to tolerate and accumulate Cu. 11 Different taxa to be isolated has been isolated during two sampling campaigns (in Autumn and in Spring). Among these, Clonostachys rosea, Trichoderma harzianum, and Aspergillus alliaceus were tested at increasing Cu(II) concentrations and showed a Cu(II)-tolerance capability ranging from 100 to 400 mg L(-1). Moreover, the strains of T. harzianum and C. rosea presented a high Cu(II)-bioaccumulation capability, 19628 and 22,222 mg kg(-1), respectively. These microfungi may be fruitfully exploited in mycoremediation protocols.

Keywords: Bare soil; Derelict mine; Fungi; Metal tolerance.