Change in the vegetation of the Karakanskiy ridge near surface coal mines

Abstract

We investigated changes in the structure of plant communities (floristic composition and species activity) under the influence of anthropogenic and technogenic factors. The studies were conducted in close proximity to rapidly developing surface coal mines and areas of intensive agriculture (Karakanskiy ridge, Kemerovo Region, Russia). The Karakanskiy ridge is located submeridionally and cuts the Kuznetsk Basin into the eastern and western parts (See Fig. 1). On the west side, at present, 15 opencast coal mines are being built. Technogenic factors that can affect vegetation include high contamination of the territory with coal dust and heavy metals. Anthropogenic influence is associated with mowing grass, recreation, and berry picking. The research was carried out in 2012-2015 on monitoring platforms (MP) of two transects located across the ridge with different levels of anthropogenic and technogenic impact (See Fig. 2, Table 1). Similar plant communities, not subject to anthropogenic and technogenic effects, were taken as control sites. We investigated the species richness of the MP, the partial cover, the number of genetes and ramets for each species (See Table 3). The relevés of elementary one sq. meter study plots were pooled in integrated botanical information system IBIS. The images of projections of the covers of plots were processed in the graphic editor PaintNET. Microsoft Excel spreadsheet processor was used for partial covers calculation. For indirect ordination, detrended correspondence analysis (DCA, a variant of factor analysis) was used to analyze the activity of species, derived from their mean percentage cover and constancy over elementary plots in each MP. To compare the species composition in the monitoring sites, UPGMA-clustering using Czekanowski/ Dice / Sørensen coefficient was applied to group joint floras of MPs. A total of 200 elementary plot relevés was analyzed. As a total, we identified 236 species of vascular plants for ten MPs. The annual number of species on single MP is in the range of 25-52 plants per m2. The difference in number of species by year has a fluctuation character and in most cases does not exceed confidence intervals. The biggest coefficients of variation were registered for the MPs of the southwestern slope (MPs 3, 4 and 7), where the strongest influence on phytocoenosis is caused by ground fires, as well as pollution from open-cut coal mines. The lowest coefficient of variation in the floral composition is scored in the areas with the minimal anthropogenic impact (control sites). Ruderal plants and meadow weeds (Pimpinella saxifraga, Poa angustifolia, Dactylis glomerata, Festuca pratensis, Veronica chamaedrys, Taraxacum officinale, Plantago media) are present in a floristic composition with a high constancy class after a long-term mowing (See Table 4). They replace species of post-forest meadows - Brachypodium pinnatum, Galium boreale, Trollius asiaticus, and Hieracium umbellatum. As a result of berrying and recreation, the species more characteristic for upland meadows (Phlomoides tuberosa, Calamagrostis epigeios, Sanguisorba officinalis, and Cirsium setosum) appear in plant communities. Strong ground fires lead to the formation of a vegetation with lower constancy classes species. The revealing of effect of the technogenic factor on species composition and species activity is not yet possible. The variability of species activity values is approximately the same in the control and in most MPs located on the northeastern slope represented by the post-forest meadows. The plant communities located on the northeastern slope occupy a special position, which should be genetically associated with forest meadow communities, but under the influence of longstanding haymaking the changes in the floristic composition and activity of species have undergone significant transformation. Picking berries and partially trampling the grass stand also changes the structure and parameters of vegetation. Despite the fact that this is a temporary factor, the species composition and activity on such MPs differs markedly from similar sites.