Ukrainian Journal of Forest and Wood Science (Nov 2021)
Structural features of the forest litter of water protection pine stands in wet hygrotopes of Zhytomyr Polissya
Abstract
The results of a study of the fractional composition, structure, and development of forest litter in water protection pine stands that grow in the prevailing wet subor and sudubrava forest conditions of Zhytomyr Polissya are presented. The age range of plantings ranges from 18-85 years. It is established that water protection pine stands in wet hygrotopes accumulate significant reserves of forest litter, which range from 33.0 t/ha in young stands to 77.0 t/ha in mature plantings. The distribution of forest litter by area in most plantings is uniform, although, in young stands, a large proportion of it accumulates in the row spacing. In terms of composition, the forest litter of pure pine stands is characterised by an average dense structure, and in pine forests with an admixture of deciduous species, the litter is usually loose, which is conditioned by the presence of annual fallen leaves in its upper horizon. The thickness of the forest litter in the row spacing of young stands varies between 2.6-2.9 cm without its clear distribution on the horizons. In middle-aged plantings, horizons are clearly distinguished in the litter profile. The total thickness of the litter reaches 4.0- 4.3 cm. In ripening and ripe pine stands, the thickness of the forest litter ranges from 6.0-6.3 cm. In plantings of older age groups, the forest litter has a predominantly three-layered structure. The trend of intensive accumulation of forest litter in wet subor and sudubrava conditions up to the age of ripeness is revealed. In ripening plantings, the accumulation of litter slows down, in mature plantings, the processes of accumulation and decomposition of litter are levelled. The tendency of the predominance of the active part and, accordingly, a decrease in the inactive litter fraction in ripening and mature plantings of wet sudubrava in comparison with subor conditions is established, which indicates more active processes of litter mineralisation in wet sudubrava conditions
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