The article discusses methodological aspects of biomass and productivity assessment on the example of three common species of hypoarctic shrubs (Salix glauca, Betula exilis, Vaccinium uliginosum). The authors present the algorithm for measuring and calculating the fractional composition of aboveground biomass and annual productivity using the index of biomass annual increment. The application of shoot increment as an index of annual productivity leads to a systematic underestimation, since it does not consider the wood increment of stems in the process of radial shoot accumulation. The study found that there was no significant correlation between shoot age and shoot length and shoot base diameter. The investigations showed no or weak correlation of shoot mass with shoot length and strong correlation with shoot base diameter. Shoot mass dominates the total aboveground phytomass of all species, with a share of 63 to 71%. The relative rate of shoot phytomass accumulation varies between species from 7 to 10%. The moisture content of the shoots of the examined species is stable and varies in the range of 59-64%.
Bondarev et al. (Fri,) studied this question.