• Korean Journal of Medicinal Crop Science
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• v.6 no.1
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• pp.44-50
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• 1998

The experiment was carried out to investigate weed occurrence in peony field. The number of weeds was Compositate 9 species, Gramineae 4 species, Craciferae 3 species, Eugarviaceae, Polygonaceae and Scrophularilaceae 2 species, respectively. Weeds classified by life cycle were annual weed 19 species (57.6%), biennial weed 8 species (24.2%), and perennial weed 6 species (18.2%). Weed species and dominance rate by morphological characteristics were grass weed 4 species (12.1%), broad leaf weed 25 species (84.8%), and sedge weed 1 species (3.1 %) . Major dominant weeds were Capsella bursa-pastoris, Chemopodium album var. centrorubrum and Equisetum arvense in late April, and Digitaria sanguinalis, Erigeron canadensis and Echinochlor crus-galli in late June, and Digitaria sanguinalis, Erigeron canadensis and Echinochlor crus-galli in middle August.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.210-219
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• 2007

The benthic marine algal flora and community structure were examined at five sites of the Taean Peninsula, Korea, during July-August 2005. Ninety-six algal species were Identified, including 14 green, 21 brown, and 60 red algae, and 1 marine plant. The common species that occurred at the five sites were Sargassum thunbergii, Gelidium divaricatum, Caulacanthus okamurae, Gracilavia vermiculophylla, and Neorhodomela aculeata. Sthunbergii was the dominant species in terms of coverage and biomass at ail of the study sites. The average biomass varied from $23.72g/m^2$ in dry weight at Chaeseokpo to $66.43g/m^2$ at Padori. The species could be divided into six functional groups in terms of morphological characteristics: 41 coarsely branched forms, 25 filamentous forms, 16 sheet forms, 7 thick leathery forms, including the marine plant Phyllospadix iwatensis, 4 crustose forms, and 3 Jointed calcareous forms. The seaweed communities at the five study sites were unstable and the environmental conditions were bad or very bad. Among the five study sites, the ecological evaluation index (EEI) and diversity index (H') were maximal at Padori at 2.29 and 1.98, respectively. By contrast, the dominance index (DI) was minimal at Padori (0.55) and maximal at Baramarae (0.96). Therefore, we conclude that the rocky shore at Padori has the best environment among the five study sites, although the species richness and biomass of seaweeds have declined continuously over the last 10 years.

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.295-307
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• 2015

Surveys of weed species in paddy fields were conducted to identify weed occurrence on July 2013. Total 237 sites of paddy fields in 9 City/Gun, Jeonnam Provinces in Korea were investigated. From the survey, 45 weed species in 18 families were identified and classified to 33 annuals and 15 perennials. Based on the occurrence ratio, the most weed species belonged to Poaceae (9 species) and 8 and 4 weed species belonged to Cyperaceae and Scrophulariaceae, respectively. These 21 weed species in the most four families accounted for 46% of total weed occurrence. The most dominant weed species in Korean paddy fields were Echinochloa spp. (18.5%), followed by Monochoria vaginalis (12.3%), Lemna perpusilla (8.2), Eleocharis kuroguwai (5.2%) and Scirpus juncoides (5.2%). The most dominant weed species in machine transplanting paddy fields were Echinochloa spp. (14%), followed by Monochoria vaginalis (12%) and in water seeded rice paddy fields were Echinochloa spp. (25%), followed by Monochoria vaginalis (11%). This information could be useful for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods in paddy fields.

• Korean Journal of Plant Resources
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• v.15 no.3
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• pp.227-236
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• 2002

The study was performed to understand the actual vegetation by using the phytosociological method on Hypochoeris radicata community group in Jeju-Island. 1. Tracheophyte belonged to the flora species is composed of 194 taxa which comprise 47 families,136 genera, 171 species, 22 varieties and 1 forma (Naturally plants 16 families, 47 genera, 67 taxa, including 64 species, 3 varieties). 2. According to the character species, the Hypochoeris radicata community group vegetation was classified into two communities; Erigeron annuus - Conyza sumatrensis, Setaria viridis var. pachystachs -Zoysia sinica community, distributed species. 3. This species is distributed from the shore to 1,700m the sea, on Jeju Island. 4. In terms of dominance and sociability of Hypochoeris radicata, the Seohong-dong, Seogwipo city site ranked highest site and the Seongsan-ri, Namjeju-gun site ranked lowest. 5. Catapodium rigidium which is belonged Gramineae was for the Hirst time found in JeJu.

• Journal of Plant Biology
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• v.15 no.1
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• pp.1-12
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• 1972

As part of the study of the structure and the successional trends of our temperate forests, a quantitative survey was made of the relatively well conserved forest stands on Mt. Kwanak, Seoul. Three community types were observed; the Pinus densiflora-Quercus mongolica community, the Pinus densiflora community, and the Quercus mongolica community. Evidence suggests that the dominance of Pinus densiflora and quercus mongolica will continue in the Pinus densiflora-Quercus mongolica community, however, in the Pinus densiflora community the dominant species, Pinus densiflora, is now being replaced by Quercus mongolica. The trend toward an increased in Acer pseudo-sieboldianum var. koreanum, Fraxinus rhynchophylla, Carpinus cordita, and Acer mono is observed in the Quercus mongolica community. An analysis of the overall composition of the forest reveals that the upper story is mostly occupied by Quercus mongolica and Pinus densiflora, the shrub layer by Rhododendron schlippenbachii and Lespedeza maximowiczii, and the herb layer by Spodiopogon cotulifer and Artemisia keiskeana. Quercus mongolica may cover most part of the forest, gradually excluding Pinus densiflora. Acer pseudo-sieboldianum var. koreanum, Fraxinus rhynchophylla, Carpinus coradata, and Acer mono are increasing in importance with the potentiality of developing into major canopy components. With the diversification of the physical habitat Cephalotaxus koreana and Magnolia sieboldii, the species which had almost completely been eliminated form the forest through the severe interferences, have reappeared.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.321-327
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• 2010

We performed diagnostic PCR assays and a phylogenetic analysis using partial sequences of TEF1 (translation elongation factor-1) to determine the trichothecene chemotypes and genetic diversity of F. graminearum isolates from maize and rice samples collected in 2009 in Korea. PCR using a species-specific primer set revealed a total of 324 isolates belonging to the putative F. graminearum species complex. PCR with trichothecene chemotypespecific primers revealed that the nivalenol (NIV) chemotype was predominant among the fungal isolates from rice (95%) in all provinces examined. In contrast, the predominant chemotype among the corn isolates varied according to region. The deoxynivalenol (DON) chemotype was found more frequently (66%) than the NIV chemotype in Gangwon Province, whereas the NIV chemotype (70%) was predominant in Chungbuk Province. Phylogenetic analysis showed that all DON isolates examined were clustered into lineage 7, while the NIV isolates resided within lineage 6 (F. asiaticum). Compared with previous studies, the lineage 6 isolates in rice have been predominantly maintained in southern provinces, while the dominance of lineage 7 in maize has been evident in Gangwon at a slightly reduced level.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.6
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• pp.1-17
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• 2016

The study was aimed to understand the ecological status of the Maebongsan urban forest in Cheongju-si through investigating the vegetation, soil characteristics, and soil microarthropods. Phytosociological analysis for twenty plots revealed that the plant communities were classified into Pinus rigida community, Robinia pseudoacacia community, Castanea crenata community, Quercus acutissima community, Pinus strobus community, Pinus koraiensis community, and Larix kaempferi community. The importance value showed that afforestation tree species like Castanea crenata, Robinia pseudoacacia, and Pinus rigida dominate the urban forest. DBH analysis indicated that although the plant communities seem to be under the succession to Quercus forest, the dominance of Castanea crenata and Robinia pseudoacacia might still persist for several more decades. The properties of soils from the plant communities showed that loamy sand and sandy loam in soil texture, low organic matters, and severe acidification. The abundance of soil microarthropods were not different among the plant communities except Castanea crenata community and Pinus koraiensis community. The two communities showed especially low abundance of collembola and acarina. Thus, we can say that Castanea crenata community and Pinus koraiensis community seem to have been influenced strongly by anthropogenic activities.

• Journal of Plant Biology
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• v.28 no.1
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• pp.79-93
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• 1985

Plant succession and subsequent changes of soil properties were studied in sand bars at the Nagdong River estuary in Korea. By old maps, ages of sand bars such as Namusitdeung, Galmaegideung, Baeghapdeung and Ogryudeung were estimated about 10, 15, 25 and 60 years old, respectively. The dominance-diversity curves and plant species diversity indices among the sand bars showed increasing trend of stability from Galmaegideung toward Ogryudeung. The soil acidity, contents of organic matter and total nitrogen of soil increased significantly from Galmaegideung toward Ogryudeung. The order of successional degree among the sand bars on the basis of the number of plant species, the results of vegetation analysis and changes of soil properties almost coincide with the order of age among the sand bars. However, the order of successional degree between Namusitdeung and Galmaegideung was more or less obscured because of cyclic succession driven by allogenic processes.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.246-256
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• 2012

This study intended to investigate the distribution of natural habitats, and the environmental factors, vegetation and soil analysis at 22 different sites of 9 regions in order to understand the environmental characteristics of $Adoxa$ $moschatellina$ in Prov. Gangwon-do. Natural habitats are confirmed at 44 regions of 14 cities and counties except for Donghae-si, Sokcho-si, Gosung-gun and Yanggu-gun in Prov. Gangwon-do. Natural habitats were located at altitudes of 99-1,084 m with slope inclinations of $0-25^{\circ}$. A total of 215 vascular plant taxa are identified from 22 quadrates. Importance value for members of the herbaceous (H) layer were as follows: $Adoxa$ $moschatellina$ 32.8%; $Meehania$ $urticifolia$ 7.5%; $Cardamine$ $leucantha$ 5.1%; $Scopolia$ $japonica$ 3.8%; $Corydalis$ $remota$ 3.3%. The importance value of the last four species are high, so they are at affinity with $Adoxa$ $moschatellina$ in their habitats. Species diversity of investigated sites ranged 0.4870-0.9848, and that of evenness and dominance are 0.4525-0.7601 and 0.1335-0.4191, respectively. Cluster analysis based on importance value appeared the high relations with differences of dominance species. Field capacity of investigated sites ranged 4.29-38.45%, and the soil pH and organic matter were 4.61-5.98 and 2.44-20.21, respectively.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.64-78
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• 2015

The environmental characteristics of Astilboides tabularis were investigated to compile basic data for conservation and restoration. Natural habitats, according to investigations, were mostly located on the slopes of mountains facing north at an altitude of 432 m to 1,413 m above sea level with angles of inclination ranging from 16 degree to 49.5 degree. A total of 246 vascular plant taxa were identified from 12 quadrats in 11 habitats. The importance value of Astilboides tabularis is 20.40%, and 6 highly ranked species such as Dryopteris crassirhizoma (4.56%), Rodgersia podophylla (3.72%), Astilbe rubra (2.81%), Carex siderosticta (2.67%), Ainsliaea acerifolia (2.65%), and Meehania urticifolia (2.46%) are considered to be an affinity with Astilboides tabularis in their habitats. Average species diversity was 1.23, dominance and evenness were found to be 0.11 and 0.86, respectively. The litter depth above the soil surface was 2 to 10 cm, and soil depth was 20.8 to 67.5 cm. The soil texture of habitats were divided three types such as loam, silt loam, and sandy loam. The soil pH was 5.63 to 7.74, and the organic matter and nitrogen contents were ranged from 8.88 to 42.55%, and 1.40 to 6.58 mg/g, respectively.