• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.285-293
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• 2009

This research had been executed to find out the structure of Magnolia obovata community, a dispersal range and characteristics of scatter investigation, and to prepare management measure of it. In the result of this study, Magnolia obovata was distributed in a native plant community from planting trees of UNESCO Peace Center. The maximum numbers of Magnolia obovata were found in $20{\sim}100m$ from trees of mother. Seed of Magnolia obovata has a characteristics of gravity dispersal. But some individuals was found in 420m from its tree of mother. Seeds of Magnolia obovata has a characteristics of animal dispersal, too. Major species of animal dispersal are Garrulus glandarius, Ciurus vulgaris coreae, and Tamias sibiricus asiaticus in the study site. The importance value between native plants and Magnolia obovata had a negative relation. Because Magnolia obovata is more shade tolerant than other trees. Also, the growth of Magnolia obovata is faster than other trees. And so if the influence of Magnolia obovata reduce, it is necessary to expand native plant community, and to cut Magnolia obovata over 10m of the height and over 10cm of the DBH, for preventing influence of Magnolia obovata.

• Journal of Forest and Environmental Science
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• v.28 no.1
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• pp.1-7
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• 2012

Tropical forests whether fragmented or undisturbed or be they equatorial or deciduous, remain the storehouse of biodiversity for hundreds of thousands of plant and animal species. This unique characteristic continues to attract a wide range of scientists and international organizations to study and attempt to understand tropical forest ecosystems. Gene flow is mediated by pollen, seed and seedling dispersal, and factors affecting this gene flow include phenology, spatial distribution, population structures, seed predation, sexual and mating systems as well as physical and biological barriers to gene flow. Two methods are used in measuring gene flow: direct method that relies on the actual observation of seed and pollen dispersal, whereas indirect methods involve the use of genetic markers such as allozymes and DNA techniques. Political strife, extreme natural and artificial disasters, the lack of a comprehensive forestry research vision, coupled with difficult socio-economic conditions in Africa have made the environment quite difficult for sustained research activities on the part of those undertaking or wishing to undertake such studies. Gene flow studies in this region are few and far between. This review elaborates on the mechanisms of gene flow mediation in Sub-Saharan Africa.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.247-252
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• 2006

For the spring ephemeral and myrmecochorous perennia, Corydalis filistipes Nakai (Fumariaceae), rare and narrow endemic to Ullung Island in Korea, genetic diversity and structure of 4 subpopulations of the species were investigated with allozyme markers. Levels of genetic diversity (A=1.73, $P_{95%}$=61..2%, Ho=0.201, He=0.167) were relatively lower than those of other endemic species with widespread distribution range, but considerably higher than other endemic species with similar life history traits isolated in island. The moderate level of genetic diversity within subpopulations in C. filistipes is characteristic of the species with predominantly outcrossing, myrmecochorous seed dispersal by dual function of the elaisome and mode of sexual and asexual reproduction by the cleistogamy. The analysis of fixation indices showed an overall excess of heterozygotes (mean $F_{IS}=-0.1889,\;F_{IT}=-0.1226$) relative to H-W expectations. About 5.6% of the total genetic variation was found among subpopulations ($F_{ST}$=0.0557). The strategies of reasonable conservation and management, and the maintenance mechanism of genetic diversity of Corydalis filistipes Nakai, endemic plant species in Korea were discussed.