• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.235-258
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• 2006

The monitoring of vegetation and water quality before(2003), during(2004) and after(2005) the restoration work of Cheonggye Stream indicated that $BOD_5$ concentration before the project averaged 51.1mg/L and that both the inflow of water from Hang River and the funnel of subway station water into the stream lowered the $BOD_5$ to 3.3mg/L, improving its water quality to the third grade. Species of plants slightly increased from 121 to 132 after the restoration. Specifically, perennial plant comprised 35.6%, an increase from 24.8% recorded before the restoration. Phragmites communis and Zoysia japonica communities were observed as the introduction vegetation. However, Humulus japonicus and Erigeron canadensis communities, which were classified into the first grade according to the vegetation conservation classification, were found to be still prevailing though they were dominant community before the restoration, meaning that the ecological condition of plants had not changed very significantly. An the other hand the water quality of the reference reach was classified into the first grade based on $BOD_5$, which implies the water quality of the section was better than the project reaches. Besides the section had more diverse plant species which numbered 154, and furthermore, the rate of immigrated plants comprised 13% which was lower than 28.8% recorded by the project sections. The project reaches are considered to be inferior to the reference section in terms of ecological condition. The effectiveness of the stream restoration cannot be determined only by such short-term investigation as was conducted in this study, and it is considered that the effectiveness of the restoration of Cheonggye Stream can be determined only if investigations in other major factors are conducted over the long-term period.

• Journal of Radiation Industry
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• v.9 no.3
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• pp.119-126
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• 2015

In Shinjeong-dong of Jeongeup, there are three government-supported research institutes and an RFT industrial complex which is currently being established. Increased human activities can affect flora and fauna as a man-made pressure onto the region. As a baseline study, status of exotic plants was investigated prior to a full operation of the RFT industrial complex. A total of 54 species and 1 variety of naturalized or introduced plants were found in the study area. Among them, three species (Ambrosia artemisifolia var. elatior, Rumex acetocella and Aster pilosus) belong to 'nuisance species', and four species(Phytolacca americana, Iopomoea hederacea, Ereechtites hieracifolia and Rudbeckia laciniata) to 'monitor species' designated by the ministry of Environment. Some of naturalized trees and plants were intentionally introduced in this area, while others naturally immigrated. Physalis angulata seemes to immigrate in the study area in the form of mixture with animal feeds as its distribution coincided with the transportation route of the animal feeds. Liquidambar styraciflua is amenable to the ecological investigation on the possible expansion of the species to the nearby Naejang National Park as its leave shape and autumn color are very similar to those of maple trees. The number of naturalized plants around the RFT industrial complex will increase with an increase in floating population, in human activities in association with constructions of factories and operations of the complex. The result of this study provides baseline data for assessing the ecological change of the region according to the operation of the RFT industrial complex.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.221-227
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• 2007

Stink bug species and host plants occurred in fallow lands for rice product regulation were studied in Honam area from 2004 to 2005. A total of 26 bug species in 8 families were surveyed in the fallow lands. Population density of Cletus punctiger adult reached its peak in July and was higher in fallow lands close to mountain area in Muan. Population density of stink bug species occurred in plain area of Wanju were significantly low in 2004 and population density of C. punctiger adult reached its peak in July and August in fallow lands in 2005. Five species of stink bug including C. punctiger immigrated from fallow lands to rice fields in August, and three other species including Cletus schmidti in September. Eight stink bug species which were observed to feed on weeds in fallow lands were C. punctiger, C. schmidti, Eurydema gebleri, Pachygrontha antennata, Trigonotylus caelestialium, Aelia fieberi, Eysarcoris aeneus, and Nezara antennata.

• Research in Plant Disease
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• v.16 no.2
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• pp.109-114
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• 2010

The occurrence factors of Rice stripe virus (RSV) in Chungcheongbukdo were analyzed by investigating the viruliferous insect rate (VIR) of overwintered small brown plant hopper (SBPH), the population density of SBPH, the infection rate of natural host plants, and the occurrence rate of RSV on rice paddy fields at the 3 areas of Cheongwon, Jincheon, and Boeun in 2008 and 2009. The average VIR of overwintered SBPH was 0.0% in 2008 and 1.1% in 2009. From SBPH collected on early June in 2009, VIR was higher as 1.4% at Jincheon and 4.2% at Boeun than those of overwintered SBPH, and this higher VIR might relate stronlgy with the adult population of SBPH immigrated from China. The populations of SBPH at Cheongwon, Jincheon and Boeun in 2008 were 3.8, 7.5 and 20.8 Head/$m^2$, respectively. However, those of Cheongwon and Jincheon increased up to about two folds as 8.4 and 13.1 in 2009. No RSV was detected on the natural host plants including barley. The factors involved in RSV occurrence were affected negatively by the low VIR of overwintered SBPH, the low population of overwintered SBPH, the low infection rate of RSV on the natural host plants, and the clean cultivation environment in Chungcheongbukdo.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.305-309
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• 1983

To know the effect of desaltation in the reclaimed tidal fields on the succession of vegetation and on the root hair formation of paddy rice, reclaimed fields in Kang Hwa Island, Nam-Yang Bay and Ke-Hwa Island were investigated during summer crop season in 1982. The obtained results can be summarized as followings. l) In the highly salty and water logged areas of reclaimed tidal fields, the first dominating species of higher plant were observed to be Salicornia herbacea L. and Suaeda japonica Makino. With the continued desaltation, Chemopodium virgatum Thumb. occurred in the vegetation. After this transition, the dominating species were composed of Scirpus maitimus L. and Phragmites communis Trin. At the S. maitimus and P. communis dominating salinity level, rice cultivation was safe from the salt damage. 2) In the water logged area, Artemisia capillaria Thunb. and Aster tripolium L. took the place of dominating species after S. herbacea and S. japonica. At this salinity level, graminaceous weeds began to immigrate. 3) In dry areas, Suaeda asparagoides Makino and Suaeda maritima were the first appearing dominant species. Atriplex subcordata Kitakawa was also observed in sucy dry areas, but colony formation was not observed. 4) Plants immigrated slowly into dry areas from the already vegetated water logged areas with the continuation of desaltation. 5) The high soil salinity level affected the root hair formation of rice by reducing both the rate of root hair formation and the length of root hairs.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.183-190
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• 1986

Identification of fruit sucking moths, their larval host plant, and degree of damages to fruits were investigated in $1982{\sim}'83$ at two orchards in Cheonnam province. In this study, 4 families 30 species were collected as fruit sucking moths and among them 10 species are newly recorded in Korea as fruit sucking moth: Catocala electa(B.), Spirama helicina(H.), Erebus ephesperis(H.), Parallelia stuposa(F.), Simplicia niphona(B.), Marumba gaschkewitschii(B. et G.), Agrius convolvuli(L.), Thyatira batis (L.), and Spilosoma niveum(M.). Larval host plants of fruit sucking moths in the vicinity of the fruit orchard include Cocculus trilobus D., Albizzia julibrissin D., Pterocarya rhoifolia S., Jaglans mandshurica M., Solanum melongena L., Brassia campestris S., Rubus idaeus C., Thalictrum aquilegifol L., and Rhus succedanea L. As the damage on different varieties of the main fruit trees, plum was orderly Santa Rosa>Beauty, Apple was Chook>Hong Og, Peach was Choseng Baeg Do>Hwang Do>Baeg Do, and Grape was Campbell Early>Neo Mascat>Golden Queen. Seasonal occurrence of main fruit sucking moth Spirama retorta(C.) showed peak 3 times in early-July, late-July, early-September. Oraesia emerginata(F.) showed peak 3 times in late-July, early-August, early- September and Lagoptera juno(D.) showed peak only in late-July and Adrias tyrannus amurensis(S.) showed peak only in mid-July. Fruit sucking moths were immigrated from p.m. 6 to a.m. 2, with peak in p.m. 10 to p.m. 12.