Post-fire succession in coniferous-broad-leaved forests of the Anyuskiy national park

Abstract

Forest ecosystems of the Anyuy river basin were chosen as the object of study, which have undergone significant changes due to wood harvesting, starting in the 50–60s of the twentieth century, and catastrophic fires in the late 1990s and early 2000s. The purpose of the study was to study the course of post-fire succession in the coniferous-deciduous forests of the Anyuysky National Park, for which 21 sample plots were established in the mountainous part of the basin of the middle and upper reaches of the Anyuy river, on its the right bank, in places affected by forest fires in different years. Quantitative recording and assessment of silvicultural and forest survey indicators of the stand, the lower stand layer and undergrowth were carried out on the sample plots. During the study, it was found that throughout the surveyed territory, young flat-leaved birch (Betula platyphylla Sukaczev) trees aged from 15 to 30 years were formed with a single participation of broad-leaved species, such as small-leaved maple (Acer mono Maxim.), Take linden (Tilia taquetii C. K. Scheind.), Mongolian oak (Quercus mongolica Fisch. ex Ledeb.), Manchurian ash (Fraxinus mandshurica Rupr.) etc. As a result of fires, due to the composition of the stands, native coniferous species disappeared as Ayan spruce (Picea jezoensis (Siebold & Zucc.) Carrière), white fir (Abies nephrolepis (Trautv. ex Maxim.) and Korean pine (Pinus koraiensis Siebold et Zucc.), which were noted in the composition of the undergrowth, and appeared there due to favorable conditions developing for these shade-loving species under the canopy of flat-leaved birch. With movement to the east and with increasing altitude above sea level, the participation of Ayan spruce in the composition of the undergrowth increases, however, in general, the species diversity in the composition of the layers decreases from 19–40 to 4–27 species. The composition of the undergrowth is dominated by flat-leaved birch and Cayander larch (Larix cajanderi Mayr), the share of the main species accounts for about 60 % of the total amount of undergrowth. Mostly, the undergrowth is reliable (78 %), 56 % of it has a height of more than 1.5 m. In the shrub and grass-shrub layers, representatives of indigenous coniferous-deciduous forests are noted: Manchurian hazel (Corylus mandshurica Maxim.), Amur barberry (Berberis amurensis Rupr.), filamentous cornflower (Thalictrum filamentosum Maxim.), Waldsteinia Maksimovich (Waldsteinia maximowicziana (Teppner) Prob.) etc.

Keywords

• regenerative succession
• forest biocoenosis
• sample plot
• tree stand
• undergrowth