Table 3 The genus identified on the basis of poorly preserved plant material collected in the Antarctic Genus Family Numbers of specimens Type of specimens Betula Betulaceae 2 Wood Carex Cyperaceae 2 Fruit BAY 1895344 molecular weight Crepis Asteraceae 1 Fruit Melica Poaceae 1 Fruit Melica Poaceae 1 Spikelet Tilia Tiliaceae 1 Wood Table 4 Identified families or groups of poorly preserved plant collected in the Antarctic Families or groups Type Numbers of specimens Cerealia Caryopses 8 Coniferae Needle 1 Dicotyledones Leaf

18 Fabaceae Seed 1 Poaceae Spikelet 16 Poaceae Leaf 8 Poaceae Stem 5 Poaceae Caryopses 3 The analyzed diaspores belong mainly to herbaceous plants, only one species of tree (Betula pendula) was represented in the collected seed material. But in vegetative remains wood fragments of Pinus sylvestris, linden (genus Tilia) and birch (genus Betula) were identified. In the collected material there were also identified needles of Pinus sylvestris and

some hard to determine fragments of needles belonging to a species from Coniferae family. We also found fragments of selleck compound a larch cone Larix decidua. Straw fragments belonging to Poaceae were present in numerous samples. Also a lot of unidentified fragments of leaf blades, characteristic to Dicotyledoneae were found in numerous samples. The whole material contained a lot of unidentified phyto-remains. All identified species belong to twenty families, representing plants from Dicotyledoneae and Monocotyledoneae (Table 3). Asteraceae and Poaceae families were the most abundant in genera: 9 and 7, respectively. The same families were also the most abundant in species: Asteraceae—10 and Poaceae—6. The most diaspore and phyto-remain specimens belonged to Poaceae and Pinaceae families, but Pinaceae were represented CX-4945 mostly by vegetative fragments, like needles. In the collected material diaspores of Asteraceae family accounted

significant participation. The most numerously represented species was Echinochloa crus-galli (caryopses and spikelet). The Polygonaceae was represented by two genera, including five species (ten diaspores). The average cumulative annual degree days during three summer season was about 1,450. The relative risk of alien vascular plants establishing for “Arctowski” oasis was high and after normalization (to provide a probability of risk from 0 to 1) reach about 0.81. Progesterone Discussion Phyto-remains and diaspores were found mainly on clothing, gear and equipment of expeditioners that had spent the previous six months in Poland, thus the probability that the majority of the investigated plant material originated from this region was very high. In our study average number of seed per person carrying plant diaspors were lower than in Chown et al. 2012a, thus probably because about half of investigated people spend about forty days at the sea, travelling from Poland to the Station with limited contact with plant propagules.