1Institute of water and ecological problems,
62, Kim Yu Chena str., Khabarovsk, 680000 Russia
e-mail: morozova@ivep.as.khb.ru
2Sumy National Agricultural University,
160. Kirova str., Sumy, 40000 Ukraine
Published data on both flora and phytocoenosis genesis and plant population dynamics are reviewed. Urbanized environment is rated as a stress factor for single plants and their communities. The change of plant population structure in cities and towns is analyzed as the important indicator of the environment quality. The problems of phytoindication of environment quality in cities and towns for its optimization are considered.