Moss bank composition on Galindez Island (Argentine Islands, maritime Antarctic)

Tall moss turf subformation, the developed form of which is known as moss banks (MBs), play an important role in maritime Antarctic terrestrial communities. In this study, the thickness, area, species richness, correlation between these parameters, ratio of brown- and black- Polytrichum strictum, and species composition of 44 alive MBs on Galindez Island, the Argentine Islands, Graham Coast, during 2013–2022, were investigated. Furthermore, the key parameters of the largest Smith MB in Galindez were compared with measurements recorded in 1976. All the MBs tended to grow on the northern slopes. MB`s thicknesses were variated from 7 to 75 cm exhibiting a moderate correlation between thickness and area. The MB bryophyte flora included 13 moss species and four liverwort species. No correlation was observed between species richness and the area of MB; however, species richness was positively correlated with MB’s thickness. The MBs species richness was possibly dependent on their age and local micro-conditions. The abundance of some bryophytes was also correlated with MB’s thickness. A comparison of the results of this study and those obtained in 1976 revealed an increase in the ratio of brown- and black- P. strictum class, no significant changes in the ratio of Chorisodontium aciphyllum, and a decrease in lichen incrustation. These results showed that the ratio of P. strictum’s colour classes, C. aciphyllum, and liverworts’ abundance can be used to evaluate the condition of the MB. The findings of this study can greatly contribute to the long-term monitoring of moss communities as indicators of global change.