Determination of Stomatic Density, Index, and Area as Exposition Biomarkers of Pollution in Deschampsia Antárctica Desv. (Poaceae)

Deschampsia antarctica Desv. (Poaceae) is the only native grass described so far for Antarctica, with a distribution mainly centered on the Antarctic Peninsula. The plants were collected at Argentinian Scientific Station Carlini, 25 de Mayo (King George) Island, to determine and evaluate in their leaves: the stomatic index (SI), density (SD), and area (SA) as pollution biomarkers. Samples were taken within the Station's influence area: (A) Supply Area (loading and unloading of fuel and supplies), (B) the area adjacent to the Electric Power Station, and (C) area of Fuel Tanks. Besides, other samples were taken from a pristine area called Peñon 7 (D). The results of SD showed significant differences only on the leaf abaxial face from the plants of the 4 studied sites: Peñón 7 (57.36 ± 2.03), Supply Area (61.30 ± 2.32), Electric Power Station adjacent area (69.56 ± 2.23) and Fuel Tanks area (80.11 ± 2.42). The SI as well as the SA did not have significant differences (p > 0.05) for all the analyzed sites. However, correlation analyses between SD and SI showed a positive and significant association only for the leaf adaxial face from all sites. From the obtained results, we could suggest that the correlation (SD-SI) on the adaxial side of the leaves was a good biomarker to estimate the degree of anthropogenic impact in each studied area.