Influence Of Species-Transformers Invasion On The Vegetation Dynamics For Fallow Land Ukrainian Polissya
Invasions of the species-transformers are reasons for changingthe processesof dynamicsnatural plantcom- munities and their species composition. Newlyformed communities often have quarantine species that are dangerous to humans and pestiferous weeds. The behav- ior ofthese speciesis oftendifficult topredict, sotheir study isextremely relevant.The purpose ofour studyis toestab- lish thepresence ofspecies atdifferent stagesof overgrowth of fallow, determining influence on vectors and rate of succession. We made 537 standard geobotanical descrip- tions.We chosespecies throughtheir abilityto radically change the ecosystem in which it penetrates. This is in accordance with the D. Richardson classification. We used the B. Yakubenko classification for determine the early stages of successions and traditional distribution of dominant biomorphs for late stages of successions. Most species-transformers are in communities of rhizome stages (69%), shrub-forest stages (69%) and forest stages (68%).The least numberof thisspecies on thesubshrub stages (19%.). Some species are found onmost stages of succession (Conyza canadensis (100%), Acer negundo (71%)), some speciesare poorly distributed(Elaeagnus angustifolia (14%), Hippopha ¸ rhamnoides (14%), Rudbeckia laciniata (14%)). Species-transformers are able to slow down the processes of the vegetation dynam- ics. Sometimes theycan leadto a complete stop, creating a catastrophic climax (Robinia pseudoacacia). Our results often correspond to the data obtained by other Ukrainian researchers of the synanthropic flora. However, there is a need to study the influence of species-transformers on dynamics indifferent edaphic conditions.