List of issues > Series «Biology. Ecology». 2016. Vol. 16
Analysis of Pine Stands Biological Productivity in Age Groups Using Forest Management Data
Author(s)
G. G. Suvorova
Abstract
Analysis of age-related changes of phytomass fractions and their ratios in common pine forest stands in Irkutsk Region was conducted. For these aim the tables and models of growth and productivity for regional modal pine forests stands with mean ratio of the tree crown area to that of the plantation 0.7 and quality class III were used. There is shown, that from 1 to 4 scale of age the whole phytomass of pine stand increases nearly 4.4 times. The stem part rises with aging from 68 to 73 % of whole phytomass at lowering parts of stem crust and needles mass from 11 to 5 % and from 10 to 8 %, in that time crown wood, roots and overground mass parts remain in practice constant – 9, 13 и 87 %. All the fractions, except needles, increase from 1 to 4 scale of age successively by 2, 3 and 4 times with insignificant advantage of roots and stems. The needle mass after 2 age group changes weakly. The ratio of needle mass to mass of separate fractions as a measure of availability of assimilates for maintenance of forest stand living mass, gradually brings down to 75, 60 and 40 % from 1 to 4 age groups. The results permit to conclude that the regulation of photosynthetic current via agening of pine forest stand is occured to evenly reducing of assimilate level entering for maintenance all the fractions of living phytomass. The lowering of stem increment in age-related row with more rapid rate cannot be conditioned by only crown photosynthesis lowering.
Keywords
pine forest stands, scale of age, phytomass fractions, stem, needles, theory of optimality
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