ПОСЛЕПОЖАРНАЯ СУКЦЕССИЯ В ЛЕСОБОЛОТНЫХ КОМПЛЕКСАХ

Abstract

The article is devoted to the study of post-pyrogenic successional changes of plant matter in the forest-mire complexes in the eastern branches of the Great Vasyugan Mire. The aim of the study was to obtain and analyze the data characterizing the post-fire dynamics of plant matter for an objective environmental assessment of the current state of forest-mire landscapes. The objects of the study were ryam communities situated between the Iksa and Bakchar rivers of the Tomsk Region and characterized by varying degrees of post-fire disturbance, which were exposed to catastrophic pyrogenic impact. Studies on the dynamics of vegetation community and plant matter at sites with varying degree of peat fire intensity were carried out for ten years. At sites with a low fire intensity, the degree of disturbance of vegetation cover was 40 – 50 %. At a mire which was exposed to the pyrogenic influence of a moderate degree, small islands with individual specimens of shrubs (Ericaceae) and small islands of Sphagnum mosses have been preserved. Mire ecosystems that have undergone a fire of the greatest intensity, are represented by burned to mineral soil depressions with islands of burnt peat. After ten years of succession in the most disturbed mire ecosystems, the percentage ratio of the above-ground phytomass to that in control sites varied within 10 % of the control phytomass. The amount of live below-ground plant matter increased very slowly, and by the tenth year of recovery, it was only 3.5 % of the stock of control underground living phytomass. The living plant matter stock at sites with moderate fire disturbance was 50 % of the control stock both in above-ground and below-ground areas. At sites of low fire intensity by the tenth year of succession, the amount of live plant matter ranged from 70–80 % of the above-ground control phytomass, and as for below-ground phytomass, the amount of living roots and rhizomes exceeded the control ones by 11 %.