Ecological and biological features of Tilia cordata Mill. in the urban environment of the Kola North (on the example of Murmansk)

The results of the first study of some ecological and biological features of the dendrointroducent Tilia cordata in the urban environment of the Murmansk region, in particular, the city of Murmansk are given in the article. The state of this plant species and the activity of its photosynthetic apparatus were studied in the course of the study. The environmental situation of Murmansk is made up of the activities of industrial enterprises, motor vehicles and the October Railway. In landscaping the northern cities of the Kola Arctic, Tilia cordata is extremely rare. In Murmansk, it was found at several sites, including the territory of the railway station. The results of the study showed that in the Far North it is possible to have two life forms of this species: woody and bushy. The state of Tilia cordata is estimated as strongly weakened, high percentage of drying plants and dead wood, the percentage of healthy plants is very low and is only 5%. Flowering Tilia cordata is celebrated in September and only in favorable years. In the age structure in equal proportions allocated old and middle-aged specimens. Soil growth conditions are not favorable for Tilia cordata due to the low levels of nitrogenous compounds and the pollution of the soil by Ni. It has been shown that chlorophyll a dominates in the photosynthetic pigment complex of leaves, the amount of carotenoids is the smallest. Two types of the ratio of chlorophyll a to b and the sum of chlorophylls to carotenoids did not correspond to the physiological norm and exceeded this parameter. In general, Tilia cordata can be recommended for landscaping the city of Murmansk, subject to proper agricultural practices.