Biological reserves of bracken fern (Pteridium aquilinum (L.) Kuhn) in the coniferous forests of Altai Krai

Abstract

The article presents information on the biological resources of the bracken fern (Pteridium aquilinum (L.) Kuhn) in the coniferous forests of the Altai Krai. Bracken fern is one of the most widespread ferns in the Altai Krai. It often dominates in grass cover in both deciduous and coniferous forests. The author gives a morphological description of the plant, characterizes the features of growth and development, considers the influence of environmental factors (temperature, humidity, lighting, anthropogenic activity) on the distribution and abundance of this species. The article provides data on biological productivity of bracken fern in different natural zones of Russia. The regularities of changes in the biological productivity of the bracken fern were revealed depending on the habitat conditions. In the Altai Krai, commercial harvesting of bracken fern is carried out in various types of forests. Long-term exploitation of the same lands leads to a decrease of resources and disruption of the natural populations’ structure. To study the current state of populations and identify the biological and commercial stocks of bracken, we examined coniferous forests (fir and pine forests) in the zones of mass harvesting of bracken - in the Priobsky Bor area and in the Salair ridge zone. In the study area, 68 key sites in various groups of forest types were established by random sampling. At each site, geobotanical descriptions of the forest community were carried out, the number of fronds, the density of standing, the projective cover and the average weight of one frond were determined. The data obtained are extrapolated to the entire study area. Studies show an extremely uneven distribution of bracken fern in forest types and individual regions. During the research period, the biological, economic and operational stocks of bracken fern were determined and recommendations were given on the amount of annual harvest in various types of forests.