Factors of Formation of Communities with Ambrosia artemisiifolia L. on the Periphery of the Mass Distribution Zone

Abstract

The aim of this study is to identify the main environmental factors of the formation of plant communities with Ambrosia artemisiifolia L. on the periphery of the mass distribution zone in the Central Chernozem region. Four types of communities with Ambrosia artemisiifolia L. were identified in the study area. Their ecological determination is demonstrated as a result of the analysis of different species and species with the greatest activity by identifying differences in ecological regimes of habitats and DCA-ordination of releves. Habitat disturbance is a leading factor in the formation of these studied phytocenoses. The degree of habitat disturbance affects the abundance of Ambrosia artemisiifolia. Monodominant communities with the species are formed on severely disturbed sites with sparse vegetation cover. In ruderal phytocenoses with denser herbage, ambrosia is not abundant, but can it be present in them for a long time due to their periodic disturbances. Moisture of soils and substrates is the second strongest factor influencing the differentiation of communities. The studied communities are formed on a rather wide gradient of this factor. In the study area, we identified not only xerophytic communities common in many regions of Central and Eastern Europe, but also communities emerging in coastal ecotopes with variable moisture regimes. These phytocenoses are formed in sites disturbed both under human influence and under the influence of natural factors such as river spills or heavy rains. As a result, along with xerothermic technogenic ecotopes, banks of rivers are habitats of phytocenoses with high density of Ambrosia artemisiifolia.