• Korean Journal of Plant Resources
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• v.23 no.4
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• pp.261-273
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• 2010

This study intended to investigate the environmental factors including soil and vegetation in order to understand the environmental and ecological characteristics of seven different habitats of Viola websteri. These habitats, according to investigations, are mostly located on the slope of mountains facing north at an altitude of 343 m to 991 m above sea level with angle of inclination from 1 degree to 33 degrees. The type of soil is mostly sandy loam and the average field capacity of soil is 28.97%. Their average organic matter is 16.63%, soil pH 5.62, and available phosphorus is 14.75%. A total of 133 vascular plants are identified in 18 quadrates of seven habitats. Dominant species of woody plants in seven habitats are represented as Acer pictum subsp. mono and Quercus mongolica in tree layer, and Acer pictum subsp. mono in subtree layer. Importance value of Viola websteri is 9.66%, as regards the herbaceous layer, and five highly ranked species such as Meehania urticifolia(8.53%), Pseudostellaria heterophylla(6.51%), Hylomecon vernalis(5.15%), Oxalis obtriangulata (4.52%), and Pseudostellaria davidii(4.15%) are considered to be an affinity with Viola websteri in their habitats. The degree of their average species diversity is 1.32, and that of dominance and evenness are 0.08 and 0.89, respectively. Correlation coefficients analysis based on environmental factors, vegetation and soil analysis shows that the coverage of Viola websteri is correlated with silt and sand ratio, and coverage of tree layers are correlated with species richness and altitude. Cluster analysis based on vegetation structure of each habitats are forms a three groups.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.267-276
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• 2010

This study was performed to obtain basic data about vegetation structure and site environment of rare and endangered plant, viola websteri in five natural habitats. The dominant species of Hongcheon habitat were Pyrus pyrifolia (tree layer), Morus bombycis (subtree layer), Pyrus pyrifolia (shrub layer) and Isodon inflexus (herb layer). Mt. Yeonin habitat were dominated by Quercus mongolica (tree layer), Morus bombycis (subtree layer), Philadelphus schrenckii (shrub layer) and Viola websteri (herb layer). Mt. Yumyung habitat were dominated by Cornus controversa (tree layer), Morus bombycis (subtree layer), Fraxinus rhynchophylla (shrub layer) and Adenocaulon himalaicum (herb layer). Mt. Daebu habitat were dominated by Acer mono (tree layer), Staphylea bumalda (subtree layer), Staphylea bumalda(shrub layer) and Dryopteris crassirhizoma (herb layer). And the dominant species of Mt. Worak habitat were Larix leptolepis (tree layer), Fraxinus rhynchophylla (subtree layer), Alangium platanifolium var. macrophylum (shrub layer) and Adenocaulon himalaicum (herb layer). It was found out that the average acidity of soil pH was 5.23; 0.30ds/m for electron conductivity; 12.6% for organic matter content; 0.68% for total nitrogen; 21.66 ppm for available phosphorous; and 23.45 cmol(+)/kg for CEC. Interchangeable cation was decreased in order of $Ca^{2+}$ > $Mg^{2+}$ > $K^{2+}$. Viola websteri had positive association with Polygonatum odoratum var. pluriflorum and Geranium thunbergii but negative association with Poa sphondylodes. Species diversity index(H'), maximum Species diversity index (H' max), evenness(J') and dominance (1-J'), of investigated sites ranged 0.6816 (Mt. Worak)~0.9656 (Mt. Daebu), 1.0000 (Mt. Yeonin)~1.3010 (Hongcheon, Gangwon), 0.5330 (Mt. Worak)~0.8947 (Mt. Daebu) and 0.1053 (Mt. Daebu)~0.4670 (Mt. Worak) in woody layer and 1.0414 (Mt. Yumyung)~1.3295 (Mt. Worak), 1.4314 (Mt. Yumyung)~1.6435 (Mt. Daebu), 0.6984 (Hongcheon, Gangwon)~0.8356 (Mt. Worak) and 0.1644 (Mt. Worak)~0.3016 (Hongcheon, Gangwon) in herb layer, respectively.

• Korean Journal of Environment and Ecology
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• v.35 no.1
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• pp.48-67
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• 2021

Plant species exhibit current characteristics as a result of interactions with environmental conditions. The plants of Viola sp. have selected chasmogamous flowers with vigorous vegetative propagation or development of cleistogamous flowers as an adaptation strategy. Viola websteri is distributed on the Korean peninsula and the eastern part of Jilin Province, China. The center and edge of the distribution are expected to exhibit different population-dynamics. It is necessary to investigate the cause of its current limited distribution even though V. websteri has a mixed-mating strategy. Firstly, We examined the vegetation environment of habitats and evaluated its characteristics. Growth characteristics were examined through plant phenology. We then evaluated the population structure, characteristics of chasmogamous flowers, and productivity of cleistogamous flowers. Moreover, we compared population sizes between 2014 and 2018. Most habitats were located in deciduous broadleaf mixed forests adjacent to valleys. V. websteri produced chasmogamous flowers with self-incompatibility in April-May and cleistogamous flowers in June-September. The cleistogamous flower production is a strategy ensuring seed production under uncertain environmental fluctuations; these were approximately twice as numerous as chasmogamous flowers. The population structure was distinguished into stable and very unstable regions. There were sites where the population experienced a sharp decline in the 2018 compared to that of 2014. This large decline was found in the edge populations. The habitats had different microsites depending on the natural disturbances of drought and the matrix constituting the habitat, thus supporting various plants. Ensuring the production of seeds through cleistogamous flowers, it was determined that rapid seedling re-establishment and population replenishment were possible when the natural disturbance factor was removed. Environmental factors did not equally affect all populations or individuals. Therefore, it was expected that it would be able to persisted in a long time, despite the rapid decrease in the number of individuals in the population regionally. Local extinction and re-establishment are likely to repeat according to environmental change. We propose the additional population investigation based on this works are required. We also suggest a need to assess the long-term population dynamics and the genetic characteristics of chasmogamous flowers and cleistogamous flowers to establish and implement effective conservation strategies.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.365-380
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• 2009

Flora of vascular plants in mountains located at Wonju-si and Hoengseong-gun areas such as Chiak-san(1,288m), Taegi-san(1,261.4m), Obong-san(1,126.2m), Eungbong-san(1,094.9m), Eodab-san(789.4m), Deokgo-san(521.2m), Deokga-san(700.5m) and Seongji-bong(791m) was investigated from April, 2008 to May, 2009, and results from the previous researches in which voucher specimens had been presented from Balgyo-san(998.4m), Oeum-san(930.4m), Baekun-san(1,037.1m) and Chiak-san(1,288m) were included in the list of vascular plants from these areas. This investigations resulted in 804 taxa consisted of 680 species, 1 subspecies, 111 varieties, and 12 forms of 383 genera under 97 families, and totally in 973 taxa (21.14% of all vascular plants in Korea) of 818 species, 1 subspecies, 138 varieties and 16 forms of 418 genera under 105 families on addition of voucher specimens in the previous researches. Forests of the investigated areas were generally mixed of Pinus densiflora and deciduous trees. The areas with comparatively excellent vegetation were valley from Guryong-sa (temple) to Biro-bong (summit) via Seryeom-pokpo (fall) in Mt. Chiak-san, and Keunseong-gol (valley) and eastern slope from Taegibungyo-teo to Naksu-dae (fall) in Mt. Taegi-san. 10 families with abundantly collected species were Compositae, Graminae, Rosaceae, Ranunculaceae, Leguminosae, Cyperaceae, Liliaceae, Saxifragaceae, Umbelliferae and Labiatae in order, and they occuied 49.12% of all collected taxa. Endemic plants found in these areas were 38 taxa including Hanabusaya asiatica, Megaleranthis saniculifolia, and Pyrus ussuriensis var. diamantica, and rare and endangered ones were 24 taxa including Hanabusaya asiatica, Viola websteri, Viola diamantica, and Patrina saniculaefolia. Specially designated plants by the Ministry of Environment were 88 taxa including 12 taxa of 5th degree such as Woodsia intermedia, Hanabusaya asiatica, Equisetum pratense, Iris koreana, Lilium cernum, Trillium tschonoskii, Magnolia kobus(cultivated), Gastrodia elata, Polypodium virginianum, Cimicifuga heracleifolia, Megaleranthis saniculifolia and Viola websteri. 47 taxa of alien plants were found. As to 609 taxa (13.23% of all vascular plants in Korea) of useful plants, 334 taxa for the edible, 269 taxa for the medicinal, 127 taxa for the ornamental, 332 taxa for the forage, 3 taxa for the industrial raw material, 31 taxa for the timber and 13 taxa for the fiber were classified, respectively.