Study of the Young Growth of Main Forest-forming Coniferous Species in the Primary Forests of the Sikhote-Alin Nature Reserve

Abstract

This paper presents the results of studies of the young growth of main forest-forming coniferous species in four types of native cedar forest of the Sikhote-Alin nature reserve. The following types of young growth were measured: Manchurian fir (Abies nephrolepis), Ajan spruce (Picea ajanensis), Japanese yew (Taxus cuspidata), and Korean pine (Pinus koraiensis). The research was conducted during 5 field seasons from 2008 to 2012 at 4 permanent study areas. For each species, the common silvicultural parameters, distribution of height, age of young growth and dynamics of the average apical growth data for the twenty-year period were identified and analysed. It was established that the size and strength of young growth are affected by complex forest site conditions that are determined by: the composition of the parent canopy, stand age, and position in the landscape. The growing conditions for young growth conifers are more favourable in mountain cedar forests compared to cedar forests in a valley. A parent canopy of a specific phytocenosis forms a unique microclimate, significantly weakening and softening the impact of macro-climate indicators of the growing area on the value of the apical growth of young growth. Spruce young growth is the most responsive to changes in climatic parameters and Korean pine young growth is the least responsive.