Microalgal communities from ornithogenic soils at Cierva Point, Antarctic Peninsula

• Main Authors: Mataloni, G., Tell, G.
• Format: Journal/Newspaper
• Language: unknown
• Subjects: community composition; microalga; seabird; Site of Special Scientific Interest; soil microorganism; species diversity; trophic status; Antarctica; algae; Aves; Bacillariophyta; Chlorophyta; Cyanobacteria; Spheniscidae; Antarc*; Antarctic; Antarctic Peninsula
• Online Access: https://hdl.handle.net/20.500.12110/paper_07224060_v25_n7_p488_Mataloni

Microalgal communities inhabiting three soil sites with different degrees of influence from penguin colonies within and near the Cierva Point Site of Special Scientific Interest (64°10′S, 61°01′W) were analysed and their species composition and diversity compared with those in nearby mineral soils. Concentrations of NH4-N and PO4-P increased drastically as a function of the degree of use by the penguins. Thins chemical variation was accompanied by changes in algal community structure: chlorophytes and diatoms dominated the less enriched site, while cyanobacteria were the exclusive dominants at the most enriched site. A significant fraction (28%) of the recorded species were also present in the mineral soils, but their abundances decreased with nutrient concentration. Biodiversity as measured by the Shannon diversity index was lower than in the mineral soils, and dropped from 1.79 to 0.44 with increasing influence of the bird colonies. These observations indicate that soil algal biodiversity decreases with increasing trophic status, as recorded for freshwater phytoplanktonic communities.