Gypsum content influences culturable soil fungal communities in semi-arid steppes from central Spain

Abstract

Although gypsum outcrops are considered biodiversity hot-spots, soil fungal communities from these ecosystems have been scarcely studied. As with plants, it is expected that the establishment and growth of fungi is restricted by soil gypsum content, but information on the distribution of fungi in relation to gypsum content is lacking. Soil fungal composition and diversity were assessed and compared in different gypsum soils from Central Spain employing fungal cultures. A total of 1801 colonies were obtained in culture, isolated, morphologically and genetically identified, representing 59 fungal species. Although no differences were observed in species richness and diversity in relation to soil gypsum concentration, species composition differed both in terms of presence and abundance. Certain species were present and abundant at soils with high gypsum concentrations but not being specifically restricted or indicator to them. In contrast, other species were abundant in soils with low gypsum concentration but were not found in soils with a high gypsum concentration. These results support the existence of fungi tolerant to high gypsum concentrations (gypsovags) but do not show evidence of a specialized and restricted mycobiota (gypsophiles) in gypsum soils.