• Title/Summary/Keyword: 종수의 기대치

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Bird Diversity on Area around the Ulsan Mosaic Landscape (울산지역 모자익 경관에서의 조류 다양성)

  • Lee, Won-Ho;Jang, Ji-Doek;Choi, Byung-In;Kang, Sung-Ryong;Kwon, Ki-Chung
    • The Korean Journal of Ecology
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    • v.27 no.6 s.122
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    • pp.325-333
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    • 2004
  • Birds were censused to investigate the composition of landscape structure for bird diversity around Ulsan between May and November 2002. Associations with three main categories of habitat variables were evaluated: 1) amount and type of forest; 2) residual habitats not classified as forest or crops; 3) land-use variables. Cluster analysis of bird community shows the highest forest variables of $79.06\%$, and the others are residual habitat variables ($17.98\%$), land-use variables ($2.94\%$) in spring, and forest variables of $57.77\%$, land-use variables ($23.16\%$), residual habitat variables ($18.47\%$) in autumn, respectively. In Principal Component Analysis of a total of 196 sites, the populations are strongly correlated to Component I ($54.8\%$) based forest habitats and to Component II based on land-use. Species preferring sites were clearly separated with heterogenous forest along the first axis. In autumn, the populations are moderately correlated to Component I based land-use and to component II based forest habitats. Species preferring local habitats were also clearly separated. Fifty three species of 1,700 birds were recorded: Brown-eared Bulbul, Vinous-throated Parrotbill, Great Tit, Tree Sparrow and Black-billed Magpie accounted for over $60\%$ of the observed birds in spring and autumn. The important species were Brown-eared Bulbul, Vinous-throated Parrotbill, Great Tit and Tree Sparrow in spring and autumn. Four habitats in terms of their species richness were computed as follows: Wonhyosan has the highest an expected species number, $E[S_{59}]=19$. Moonsusan has the lowest expected species number, $E[S_{59}]=17$ in spring. In autumn, Kuenamsan has the highest expected species number, $E[S_{63}]=16$. Moonsusan has the lowest expected species number, $E[S_{63}]=12$. Pairwise similarity declined with increasing distance between recording site and recording site from Moonsusan-Wonhyosan (0.62), the same geographical regions clustered separately in a UPGMA cluster tree in spring, and in autumn from Moonsusan-ChungJoksan (0.53).

Species Composition Dynamics and Seedling Density Along Altitudinal Gradients in Coniferous Forests of Seorak Mountain (설악산 상록침엽수림의 고도별 종조성 및 치수 밀도 변화)

  • Kim, Ji-Dong;Byeon, Seong Yeob;Song, Ju Hyeon;Chae, Seung Beom;Kim, Ho Jin;Lee, Jeong Eun;Yun, I Seul;Yun, Chung Weon
    • Journal of Korean Society of Forest Science
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    • v.109 no.2
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    • pp.115-123
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    • 2020
  • The vertical distribution of vegetation can be classified according to the altitudinal gradient and the distribution of species along this gradient. The purpose of this study was to analyze the vegetation structure, species composition, dimensional density, and change according to altitude. These data illustrate the distribution of coniferous forest by altitude. By order of importance, the vegetation structure of this mixed forest consisted of Abies nephrolepis (12.2), Pinus koraiensis (10.86), and Acer komarovii (8.11). As a result of species composition according to the altitude, A. nephrolepis and Maianthemum bifolium increased in importance with increasing altitude. Tripterygium regelii emerged between 1,400 m and 1,600 m, which indicates that forest gaps were frequent at that elevation. The species diversity index was the highest from 1,400-1,500 m and coincided with the presence of forest gaps. The changes in A. nephrolepis of evergreen conifers increased significantly from 402 ± 5.4 ha.-1 to 528 ± 11.6 ha.-1 for two years, and decreased from 57 ± 1.3 ha.-1 to 56 ± 1.6 ha.-1 for P. koraiensis. The density of A. nephrolepis and P. koraiensis seedlings significantly increased at 1,500-1,600 m. The results of this study can be used as a basis to identify the mast seeding year with the increase or decrease of seedlings. In addition to documenting the evergreen conifer population of the Seorak Mountain, these results can be built upon for future monitoring of seedlings mortality.