• Weed & Turfgrass Science
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• v.2 no.4
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• pp.341-347
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• 2013

The survey of weed occurrence was conducted to identify problematic weed species on the paddy field. Total 524 sites of the 17 regions in Chungnam Province in Korea were investigated from June to August, 2013. In the whole region, 23 weed species were identified including 19 annuals and 4 perennials. The most dominant weed species in Chungnam paddy fields were Echinochloa crus-galli (25.3%), followed by Monochoria vaginalis (11.9%), Eleocharis kuroguwai (10.3%), Bidens tripartite (9.3%) and Aneilema japonicum (8.5%). The 95.2% of the investigation sites was determined under dominance value 1 (range of cover <10: numerous individuals) by Braun-Branquet indicating proper weed control in the paddy fields. This information could be useful for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods in Chungnam Province in Korea.

• The Korean Journal of Ecology
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• v.24 no.3
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• pp.169-180
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• 2001

The forest vegetation in Daedeok Science Town were classified as second forest vegetation and afforestation vegetation. The second forest vegetation was classified into two communities such as Pinus densiflora community and Quercus acutissima community. Also, the afforestation vegetation was classified again as Robinia pseudoacacia community, Pinus rigida community, Pinus thunbergii community, and Castanea crenata community. In this study area, we found total 217 taxa. The average species of appearance in Pinus densiflora community, Quercus acutissima community, Robinia pseudoacacia community, Pinus rigida community, Pinus thunbergii community, and Castanea crenata community were 21, 20, 20, 21, 21, and 18, respectively. There was no difference in appearance species between second forest and afforestation vegetation. We found total 12 naturalized plants taxa of Commelina communis, Phytolacca americana, Erigeron annuus, and Ailanthus altissima in the plots and total 19 naturalized plants taxa of Dactylis glomerata, Bidens frondosa, Xanthium strumarium, and Soianum nigrum in the climbing roads and forest circumferences. And so, we found total 31 naturalized plants taxa in this study area.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.699-713
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• 2012

Palustrine wetland is often used for development work and green area creation. However, the ecological characteristic of vegetation is not frequently considered in planning. Therefore, this study was conducted to investigate vegetation characteristic according to land-use of palustrine wetland and to provide basic materials in assessment of palustrine wetland and restoration and creation of wetland. Survey sites were caterogized into paddy, field, and mountain. Each category had two sites, so total 6 survey sites were investigated for vegetation. As a result, with a range of 61~92 species, total 216 taxa were confirmed, consisting of 71 families, 168 generic, 187 species, 2 variety 1 forma 1 subforma. Mountain received a high score in the evaluation score range of floristic regional indicator plants, and it was found that there were 10 families and 28 species of naturalized plant. Mountain showed low appearance, and fiddy and field showed relatively high appearance. Naturalized plants with slightly high vegetation cover ratio are Erigeron annuus, Amorpha fruticosa, Dactylis glomerata, Festuca arundinacea, Eragrostis curvula, Trifolium repens, Erigeron Canadensis, Ambrosia trifida, Oenothera odorata, Bidens frondosa, etc. Such naturalized plants should be removed to prevent terrestrialization of wetland and its harmful damages. Long-term monitoring and proper management of naturalized plants are expected to improve palustrine wetland into high quality biotope of rural area in the future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.381-400
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• 1985

Twelve species of subfamily Leuciscinae from Korea are reviewed and keys to species and genera are provided. The species include Tribolodon hakonensis, T. branti, Phoxinus phoxinus, Moroco oxycephalus, M. steindachneri, M. keumgang, M. semotilus, Zacco platypus, Z. temminckii, Opsariichthys uncirostris amurensis, Aphyocypris chinensis and Squaliobarbus curriculus. In the present study M. lagowskii and O. bidens recorded previously in Korea have to be classified to M. steindachneri and O.u.amurensis based on several characters such as caudal peduncle depth, their distributions and lateral line scales, etc. A. chinensis from Korea is easily distinguished from that of mainland China in head length and caudal peduncle length. The skull and weberian apparatus of M. keumgang, endemir to Korea are described and compared with the other species of this subfamily. The diploid chromosome number of 9 species has three patterns: 2n=50 (T. hakonensis, P. phoxinus, M. oxycephalus, M. steindachneri and M. keumgang), 2n=48(Z. platypus, Z. temminckii and A. chinensis), 2n=76 (O. u. amurensis). Polyploidization or intraspecific polymorphism of chromosome was not observed in any species studied. Both species of P. phoxinus and A. chinensis are shown to be electrophoretically distinct from other taxa examined. The genera of subfamily Leuciscinae in Korea are represented by three possible groups: 1) Zacco-Opsariichthys-Tribolodon-Phoxinus-Morco, 2) Aphyocypris, and 3) Squaliobarbus.

• Korean Journal of Environmental Agriculture
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• v.2 no.1
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• pp.35-44
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• 1983

In order to elucidate the change of plant community of natural forests caused by air pollution in the area of Mt. Dosjil of Ulsan city, 25 study subplots, 5 subplots from each 5 plots were set up. These plots lay along gradients of chronic exposure to airborne sulfur dioxide ($SO_2$), fluorides(F) and possibly other pollutants. Total nitrogen, organic matter, available $P_2O_5$, and CEC were generally depressed near industrial sourecs of air pollutants. The author found a total 7 species near sources of air pollutants and 13 species at the utmost plot from air pollutants. Number of individuals, species diversity, evenness, similarity index and biomass were generally depressed near the industrial source of air pollutants. Tolerant plants to air pollution is Cyperus amuricus, Calamagrostis arundinacea, Bidens bipinnata, Cocculus trilobus, Digtaria sanguinalis, Persicaria hydropiper, Pinus thunbergii, Ambrosia artemisiifolia var. elatior, Rhododendron schlippenbachii and Robinia pseudoacacia. It contains 4.41ton/ha of aboveground biomass of Robinia pseudoacacia in damaged forest by air pollution and 39.47ton/ha of it in the non-attacked forest. The annual net production is 0.67ton/ha. yr in damaged forest and $7.73ton/ha{\cdot}yr$ in the non-attacked forest.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.159-163
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• 1993

This research was conducted at the Crop Experiment Station to determine the changes of weed flora under direct seeded rice cultivation in dry paddy field from 1989 to 1992 and to establish an effective weed control strategy in direct seeded rice cultivation. With the continuous rice growing under direct seeded rice cultivation in dry paddy field, there were more occurrence in grasses and annual weeds while broadleaf and perennial weeds were diminished. The predominant weeds were aquatic weeds such as Eleocharis kuroguwai, Echinochloa crusgalli, and Monochoria vaginalis in machine transplanted rice paddy field while there were predominant of semi aquatic weed species such as E. crusgalli, Digitaria sanguinalis, Bidens tripartita, Aeschynomene indica, and Arthraxon hispidus in continuous direct seeded rice cultivation in dry paddy condition. Based on the vegetative analysis of weeds in terms of simpson index and community dominance, there was more distribution of weed species in direct seeded rice cultivation on dry paddy condition while only distributed with 1-2 weed species in machine transplanted rice paddy field. In similarity coefficient, there was a gradual increase up to 67% of weeds with the continuous direct seeded rice cultivation in dry paddy condition for 4 years starting from 41% of similarity coefficient.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.16-22
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• 1994

Ninty three species of domestic weeds were collected and screened for antimicrobial, antitumor, antioxidant and herbicidal activities. Among them, few showed antifungal activities. Cuscuta japonica showed inhibitory activity against Alternaria mali, Ambrosia artemisiifolia and Geranium sibiricum against Phytophthora capsici, Aster yomema and Aster pilosus against Phytophthora parasitica. Ambrosia artemisiifolia, Artemisia princeps, Artemisia capillaris, Ludwigia prostrata, Chrysanthemum zawadskii, Bidens frondosa, and Geranium sibiricum showed broad antibacterial activities. Carex chordorhiza, Artemisia capillaris, Persicaria nodosa, Senecio koreanus, Pariicum bisulcatum, Geranium sibiricum showed antiblebbing activity on human chronic leukemia K562 cell, among them, Persicaria nodosa was the strongist. Angelica decursiva, Equisetum arvense, Cimicifuga heracleifolia, Persicaria nodosa, Geranium sibiricum, Oenothera odorata, Cyperus sanguinolentus showed antioxidant activities. Ludwigia prostrata and Peucedanum terebinthaceum showed strong herbicidal activities.

• Korean Journal of Weed Science
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• v.15 no.4
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• pp.278-288
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• 1995

Weed species occurred in dry- and water-seeded rice were 14 (2 grasses, 8 broadleaves, and 4 sedges) and 12 species (1 grasses, 7 broadleaves, and 4 sedges), respectively. Dominant weed species in dry-seeded rice were Lindernia procumbens, Cyperus difformis, Cardamine flexuosa, and Cyperus serotinus in discending order. The species in water-seeded rice were Cyperus difformis, Scirpus juncoides, and Lindernia procumbens. The number of weed species emerged in direct-seeded rice was determined at about 45 days after seeding, and dry weights of weeds were increased up to 75~90 days after seeding. Timing for great increase of plant height varied depending upon weed species. Regardless of weed number emerged, the most dominant weeds until late stage of growth were Cyperus difformis, Bidens frondosa, Digitaria ciliaris and Echinochloa crus-galli in dry- seeded rice, and Cyperus difformis, Echinochloa eras-galli and Scirpus juncoides in water-seeded rice.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.8-13
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• 1996

This study was conducted to know the effect of storage period, harvesting time and light condition on dormancy breaking of major weeds. Echinochloa crus-galli, Cyperus serotinus, Aeschynomene indica, Ludwigia prostrata and Bidens tripartita had the 10 or 30% germination ability within 30 days after harvest but scirpus juncoides, Potamogeton distinctus, Aneilema japonica and Monochoria vaginalis had not germination untill 120 days after harvest of seed. C. serotinus and P. hydropiper required strong light for germination but S. juncoides, L. prostrata and B. tripartita showed the less tham 5% germination in the dark condition gerntinator. S. juncoides germination showed negative response in chemical soaking but A. japonica, B. tripartita and L. prostrata showed high germination percentage in Acetone, Chloroform and distilled water soaking during the 10 days after treatment.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.176-187
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• 2015

The weed flora in the Codonopsis lanceolata upland fields were surveyed in Hoengseong and Jeju in May, August, and October of 2014. The objectives of this study were to use the survey data for establishing weed control methods and to bring awareness of possible problematic weeds occurred in C. lanceolata upland fields in Korea. Altogether 207 weed species of 47 families were identified, of which 87 were annual, 47 species were biennial and 73 were perennial. Based on the morphological characteristic of the leaves, 182 species were broad leaves, 18 species were grasses, and 7 species were sedges. The dominance was highest in the Artemisia princeps followed by Digitaria ciliaris, Commelina communis, Persicaria longiseta and Echinochloa crus-galli etc. Fifty-nine species were exotic weeds with 29% of a total presence, of which Erigeron annuus was highest, followed by Crassocephalum crepidioides, Bidens frondosa, Hypochaeris radicata etc. In the PCA plot, weeds presented in the C. lanceolata upland fields of Hoengseong were divided into three groups, E. annuus, Sigesbeckia pubescence and C. communis communities and those of Jeju were divided into four groups, C. crepidioides-Cyperus iria, Spergula arvensis, Poa annua and Youngia japonica communities.