Alien and aboriginal flora of the Amur section of the Trans-Siberian Railway and its relationships with the characteristics of natural biomes

An inventory of alien and native species of vascular plants was taken along the Trans-Siberian Railway, from the settlement of Yerofey Pavlovich to Kundur-Khabarovskiy railway station, with the total length of 1043 km (11 % of the TSR) explored. The study encompassed sixteen railway stations located in two biomes, including Amur-Zeya Boreal Taiga with variants southern taiga and subtaiga, and Zeya-Bureya Nemoral Broadleaved Forests and Forest-Steppe ones. The highest similarity was displayed by south taiga and subtaiga variants of the Amur-Zeya Boreal Taiga biome, with Sørensen’s coefficient equaling to Ks = 46 % on embankment slopes and Ks = 45 % for rail bed, while a low measure of similarity was detected in the railway right of way (Ks = 24 %). The number of railway flora species displays a strong positive correlation with average annual temperature and average annual precipitation within the biome, and a strong negative correlation with the total number of vascular plants recorded within the biome, as well as with the biome area.