Floristic diversity of threatened woodlands of Kazakhstan formed by Populus pruinosa Schrenk

Abstract

Climate aridization and increased anthropogenic pressure pose a severe threat to natural vegetation, including coastal plantcommunities. Those located in river basins of the desert zone of Central Asia are among the most vulnerable. Of the variety of ecosystemsof the Ili-Balkhash region of Kazakhstan, forests dominated by a rare relict species Populus pruinosa Schrenk are of particular concern.This species occupies a very narrow ecological niche associated with river banks of the arid zone, which makes it very vulnerable toadverse natural and anthropogenic factors. The main objective of the research conducted was to fill the knowledge gap related to thespecies diversity of plant communities with the participation of Populus pruinosa. Another goal was to compare the results with theavailable data on the flora of similar communities from other Kazakh regions. The project has identified 98 plant species belonging to34 families and 82 genera. Among them were four species of trees (4%), ten shrubs (10%), one species of lianas (1%), and the rest wereherbs among which annuals dominated (44 species, or 45%). The flora contained endemic species from the Southern Balkhash region:Berberis iliensis, Rosa silverhielmii, Prangos arenaria, and Tulipa behmiana. Three species (Tulipa kolpakowskiana, Berberis iliensis,and Populus pruinosa) were listed in the Red Book of Kazakhstan. A significant proportion of weeds (32%) indicated a high level ofanthropogenic impact on coastal communities (primarily unsystematic cattle grazing). When compared with similar plant communitiesin Kazakhstan, the species composition was similar in terms of quality indicators, but different in its quantitative characteristics. Theresults may be used for subsequent monitoring of ecosystems with the participation of Populus pruinosa in the Ili-Balkhash region.