Assessment of the impact of the urbanized territory of Yekaterinburg city on the formation of undergrowth in the forest park zone

The parameters of the undergrowth in the forbs and berry groups of pine forest types in 9 parks in Yekaterinburg and areas of natural forest have been investigated. Data on the species composition, density, and distribution by groups of heights of plants that make up the undergrowth collected. It has been established that the transformation of the undergrowth by an urbanized environment neutralizes the influence of the growing conditions of the considered forest types on it. In the forest-park zone, an increase in the density of the undergrowth is observed in comparison with the natural forest. The specificity of the forest park undergrowth is the floristic contamination with adventive species, the number of which is close to 50% of the total number of undergrowth species. The coefficient of floristic similarity of the undergrowth, according to the Sorensen coefficient between forest parks and a site of natural forest, was 0.26-0.46. In quantitative terms, the self-seeding of adventive species in the undergrowth is less than that of native plants. The invasive activity of ash-leaved maple in city parks and its dynamics over a 10-year period are considered, using the example of one of the parks

TrnL-trnfF cpDNA polymorphism in some representatives of the genus

We present preliminary results of the trnL-trnF cpDNA region analysis for some representatives of the g. Betula, out of which B. procurva can be considered the most interesting. The disjunctive range of this species is confined to the mountain system in southeast Central Asia (Pamir-Alai). The occurrence of the birch is isolated from the main range in the mountainous part of the Urals, in the boreal forests zone and in the Trans-Ural forest-steppe. Due to high interspecific hybridization and population variability of the g. Betula, doubts were raised about the correct identification of the representatives of B. procurva. The studied genetic variability and population structure of B. procurva, B. nana, B. pubescens, B. turkestanica, B. tianshanica and B. pendula species indicate active introgression and hybridization processes. Polymorphism in all groups is significantly reduced, increasing slightly when comparing the most distant groups. The matching of the B. procurva cpDNA haplotypes (GBS) with B. pendula, B. nana, and B. pubescens shows that this trnL-trnF cpDNA site cannot be used for molecular identification of birch species by barcoding as a single marker, but this marker use is possible for determination of certain B. procurva population. Based on the studied cpDNA region (trnL-F) we found a clear geographic subdivision in B. procurva populations of the Trans-Urals and Central Asia,