Comprehensive assessment of a flora and a productivity of green planting in the city of Abakan

. The article provides information about the level of species diversity, biological and ecological composition, the dynamic of the vegetation productivity of a green planting in the city of Abakan (the steppe zone). The inventory of the flora revealed 288 species of higher vascular plants from 59 families and 183 genera. The basis of flora is the angiosperms, including 57 families (96.6 %), 179 genera (97.8 %), 282 species (97.9 %). The leading positions belong to the families Asteraceae (11.8 %), Poaceae and Rosaceae (10.8 %), Fabaceae (7.3 %). The most important genera in the flora were boreal ones – Carex , Artemisia (2.8 %), Potentilla (1.7 %). The ecological analysis showed the predominance of mesophytes (45.5 %). Perennial plants with clustered fleshy roots and short-rhizomatous ones (21.5 %) were a main biomorph. The analysis of the primary production of urban vegetation according to Terra MODIS data from 2000 to 2018 was carried out. The highest seasonal growth rates observed in 2001 and 2007, and the lowest ones were in 2004 and 2008. The average annual growth rates were 115±9 % for May, 107±5 % for June, 107±5 % for July, 119±14 % for July, and 120±11 % for August. The positive trend in the productivity of urban vegetation was established using the series criteria.

The presence or absence of a nonrandom (and time-dependent t) component in the decomposition of time series (1) was determined according to the series criterion based on the median [3]. The value of the series is compared with the sample median, and if x (t) > , then for the corresponding observation, the member of the sequence forming the series takes the sign "+", if x (t) < , then the sign "-". The hypothesis of a randomness of a series is not rejected, if the inequalities are carried out (for 5% level of a significance): (2)   , 1 96 .
where n -the length of the time series; ν(n) -the number of series; τ max (n) -the number of consecutive pluses or minuses in the longest series.
The module «Time Series/Forecasting» of the program «Statistica» was used to perform time series decomposition according to Census 1 method.
There were 288 species of higher vascular plants belonging to 59 families and 183 genera in the flora of parks and squares of Abakan. The basis of flora were angiosperms, including 57 families, which were (96.6 %), 179 genera (97.8 %), 282 species (97.9 %). Among ten most common families are Brassicaceae (5.5%), Ranunculaceae (3.8%), Lamiaceae (3.5 %), Cyperaceae (3.1 %), Boraginaceae и Caryophyllaceae (2.8 %). Groups of plants with different attitudes to soil moisture were identified for the ecological analysis [4]. Most of the flora consists of mesophytes (131 species, 45.5 %). It is normal, since there are enough habitats with favorable water regime (meadows, drainage channels banks, etc.). A group of mesoxerophytes (75 species or 26.0 %), growing along roads, paths, steppe meadows, on the outskirts of green zones, was the second. Less significant was the group of xerophytes, which has 39 species (13.5%). There are some of hygrophytes in the city (22 species or 7.6 % of the total number of species). Mesohygrophytes (17 species or 6.0 %) and hydrophytes (4 species, 1.4%) were less common. Favorable conditions for the growth of hydrophytes are created in the coastal zone of numerous water sources.
It is possible to characterize habitat conditions based on the analysis of plant life forms according to I. G. Serebryakov (1962) [5]. The main biomorphological group is the group of perennial herbaceous plants (165 species, or 57.3% of the total number of species). The most numerous were perennials with clustered fleshy roots and short-rhizome ones, According to data from the Terra MODIS primary production, the growth rates for the time series from 2000 to 2018 were calculated (Fig. 1). It is typical of the steppe zone (the second peak of the growing season). Absolute maximum of growth rates for the entire period (350%) was recorded in 2018. It is associated with favorable weather conditions and the appearance of new green zones, planting of new rapidly growing trees and lawns. To establish the presence of a trend, the values (n=398, ν (n) = 45, τ max = 14) were substituted into the system (2). Both inequalities violated; therefore, hypothesis (2) rejected, i.e. in the original time series there was a non-random component. Since the components of the series depend on the level of productivity of the season, a multiplicative model of interaction was chosen.
As a result of seasonal decomposition, components involved in the formation of a time series using the Census 1 method (Fig. 2-3 The contribution of the irregular component (change in the area of the green zones, pollution, damage) amounted to an average of about 1.00% (in the range of 0.02-1.50%), mainly a decrease in performance.
After seasonal adjustment of the series, one and less often two peaks in the development of vegetation were found (Fig. 3)