Composition And Spatial Distribution Of Tree Seedlings In Different Succession Stages Forests Of Changbai Mountain

The resource of broad-leaved Korean pine forest in the areas of Changbai Mountain has been seriously destroyed since the20th century, which resulting in a large area of secondary forest community. Spatial structure of tree seedlings was analyzed in secondary poplar-birch forests, secondary mixed conifer and broad-leaved forest and broad-leaved Korean pine forest in Changbai Mountain in this paper. This paper aims to understand the composition, spatial distribution and interannual dynamics of tree seedlings in different succession stages forests of Changbai Mountain.In secondary poplar-birch forests:most environment factors show their spatial autocorrelation; Fraxinus mandshurica,Acer mono, Acer pseudo-sieboldianum and Tilia amurensis also show their spatial autocorrelation on small scales. Environment variables and spatial variables showed strong interpretation on spatial variation of tree seedlings.Pure spatial variables exhibited strong interpretation power of56%. But only less than1%of the variation in seedlings community structure could be accounted by pure environment variables.In secondary conifer and broadleaved mixed forest:tree seedlings are rich in species and number. We analyzed species composition and spatial distribution of tree seedlings. The relationship between mature trees and seedlings was further assessed. The results showed that:1) A total of17tree species were recorded in this plot which was consistent with the composition of the mature trees. There were10865tree seedlings recorded, of which Fraxinus mandshurica seedlings4505, Acer mono seedlings1405, Acer tegmentosum seedlings1397, Acer ukurunduensi seedlings1042, Acer pseudo-sieboldianum seedlings998, Acer barbinerve seedlings884, Pinus koraiensis seedlings248, Tilia amurensis seedlings202, other species seedlings less than100;2) Seedlings of Tilia amurensis, Pinus koraiensiss and Acer were belong to the growing structures of the population. Seedlings of Abies nephrolepis, Quercus mongolica, Ulmus japonica and Populus davidiana, however, were classified to the declined structure of the population and F. mandshurica was belong to the stable structures of the population.3) Seedlings of all species were characterized by clumped distribution on the scales less than certain critical points. When the scales were enlarged beyond these points, seedlings of A. mono, A. tegmentosum, T. amurensi, A. nephrolepis were dispersed randomly.4) The spatial distribution of F. mandshurica, A. pseudo-sieboldianum, T. amurensi, A. barbinerve’s seedlings were positively correlated to their mature trees. The spatial distribution of P, koraiensis, A. nephrolepis, A. tegmentosum, A. mono’s seedlings, however, were negatively correlated with their mature trees.In Korean Pine Broadleaved Forest in Changbai Mountain as well as field censuses of seedlings and adult trees in the plot, we analyzed species composition and spatial distribution of tree seedlings. The relationship between mature trees and seedlings was further assessed. The results showed that:1) A total of1802trees were recorded in this plot. And there were9332tree seedlings recorded, of which Fraxinus mandshurica seedlings6986, Tilia amurensis seedlings832, Acer mono seedlings394, Acer tegmentosum seedlings250, Acer ukiiruntluensi seedlings123, Acer pseudo-sieboldianum seedlings289, Acer barbinerve seedlings438, Pinus koraiensis seedlings3, Quercus mongolica seedlings10;2) Seedlings of dominate tree species were characterized by clumped distribution on the scales less than certain critical points. When the scales were enlarged beyond these points, seedlings were dispersed randomly.3) The spatial distribution of dominate tree species’s seedlings were not signally correlated to their mature trees.Based on the data of the seedling plots from2010-2012, we can find that the composition of tree seedlings species in different years changes little.But the number of tree seedlings, advantage sort, newborn seedlings and mortality shows significant Interannual differences.