• Journal of The Geomorphological Association of Korea
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• v.28 no.4
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• pp.31-39
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• 2021

Gaemok, the place name of Uihang-ri, Sowon-myeon, Taean-gun, Chungnam, indicates a tombolo. This study estimated the Holocene sea level change and development process of the coastal landforms of the Gaemok and Hwanyeong Tombolos in the Uihang coast. The tombolos seemed to form at approximately 3.4 ka and the average sea level at that time was estimated to be higher than that of the present by ca. 1 m. The Gaemok area was a separated island from the Taean peninsula during the Holocene Climatic Optimum. At approximately 3.4 ka when the sea level rose again after the fall, the Gaemok area was tied to the land by formation of the Gaemok and Hwanyeong Tombolos. The falling or fluctuating sea levels after 3.4 ka have shaped the present coastal landforms.

• Journal of Plant Biology
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• v.24 no.1
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• pp.47-57
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• 1981

Girth at breast height was measured to test skewness ($g_1$) and kurtosis ($g_2$) of frequency distribution of the basal area in terms of t-test and Kolmogorov-Smirnov test for a total of forty six monocultures within Sudong and Kwhangnung area in central part of Korean peninsula in 1979 and 1980. The monocultures are about 10 to 50 years old, and four kinds: Pinus koraiensis, Larix kaempferi, Abies holophylla and Pinus rigida. Most of the sample sizes per site were ranged 70 to 110 excluding 4 sites. The number of classes interval was based on Sturges rule for each monoculture and was ranged from 5 to 10. In Sudong the range of age(yr) and basal area (($cm^2$)/tree) of the monocultures were from 10 to 20 and from 27.60 to 383. for Kwhangnung they were from 15 to 47 and mostly 102.15 to 619.14, respectively. All 43 monocultures except 1 showed +$g_1$, which ranged from 0.3 to 2.2 except six sites. Of the total 46 sites, 23 sites showed significant +$g_1$ which includes about 10 year-old monoculture. The number of classes interval with significant positive skewness ranged from 6 to 9. The data suggest that intraspecific competition in terms of stand structure seems to appear from about 10 year-old monocultures, and it may even last to about 50 year-old one. Around 24 monocultures showed nonsignificant -$g_2$ except one. Most -$g_2$ ranged from -0.12 to -0.83. Around 20 monocltures showed positive $g_2$ ranging from +0.13 to +3.841. Of the 22 +$g_1$, majority of 11 were very highly significant. Of all monocultures only 5 showed significant result from Kolmogorov-Smirnov test. Of the 4 species, Larix kaempferi seems to show density stress first then Abies holophylla, and Pinus koraiensis last. Data of this study indicate that adequate number of classes intervals and sample sizes for studying intraspecific competition in terms of basal area are 6 to 9 and 80 trees rather than 12 and 100 trees, respectively. It also suggests that most of the frequency distribution of basal area class are trimodal rather than bimodal under density stress. It is proposed that the leptokurtic distribution appears before normal distribution rather than direct change from platykurtic to normal distribution of basal area for selected stages in the development of stands.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.261-266
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• 2023

Interception data pertaining to Coleoptera, Hemiptera, Lepidoptera, Diptera, Thysanoptera, and Hymenoptera collected at the Korean quarantine border were cross-checked with new recorded species in Korea from 2015 to 2022. Overall, 45,084 interceptions belonging to the six orders were detected, and 545 species belonging to the six orders were newly reported in Korea. Of the 545 species, nine species were recorded as being intercepted at the quarantine border. Among the six orders, Coleoptera, Thysanoptera, and Hemiptera showed high numbers of interception; however, Hymenoptera revealed the highest number in new recorded species. These results indicate that recent newly recorded species in Korea are not subject to inspection at Korean borders and that the current quarantine system needs improvement.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.255-260
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• 2010

Insect diversities in non-organic and organic Chinese cabbage and pepper fields were studied in 2009. Sixty-two species in 9 orders and 24 species in 6 orders were collected in organic and non-organic Chinese cabbage fields, respectively. In pepper fields, insect diversity was also higher in organic fields than in non-organic ones. Dominance index, diversity index, richness index, and evenness index in organic fields were higher than those in non-organic fields.

• Journal of Sericultural and Entomological Science
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• v.53 no.1
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• pp.29-37
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• 2015

Since based on the revised educational curriculum, the insects and spiders in eight biology textbooks I and II of high school are as follows. In class level, two classes, Insecta and Arachnida were investigated and their frequence numbers in the textbooks were a total of 143 times. In order level, 12 orders in insecta, 2 orders in Aranea were appeared in the textbooks. The most appearing frequence number was represented in Lepidoptera (33 times) and then in Araneae (11 times). For each publisher, the most appearing frequencies of insecta and spiders was shown in Gyohaksa (23 times), and then in Hyeongseol and Centurla education research institute (21times, respectively). In the textbooks, four species were found to misidentify in their species name and five mistakes were investigated in their photos and content.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.231-237
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• 2014

This study was carried out to investigate the pest species and their damage on Asparagus officinalis. Field surveys were conducted in asparagus greenhouse in Jeju, for four years from 2007 to 2010. Total of 16 pest species belonging to 5 orders were found as follows: Thrips tabaci, Thrips hawaiiensis, Adoxophyes honmai, Spodoptera litura, Spodoptera exigua, Helicoverpa armigera, Mamestra brassicae, Ascotis selenaria, Ectropis excellens, Geisha distinctissima, Aphis gossypii, Myzus persicae, Anomala albopilosa, Crioceris quatuordecimpunctata, Acusta despecta sieboldiana and Deroceras reticulatum. Among them, T. tabaci frequently occurred and damaged asparagus plants during the whole growing seasons. C. quatuordecimpunctata and snails caused severe damages on asparagus shoots in spring harvest season. In mid-late seasons, aphids and lepidopteran species occurred and attacked asparagus plants. Of the lepidopteran pests, S. litura, S exigua and H. armigera belonging to Noctuidae occurred moderately and fed on asparagus plants. And the pest control strategy in asparagus cultivation was discussed based on the present results.

• Parasites, Hosts and Diseases
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• v.25 no.1
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• pp.13-23
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• 1987

Total of 216 animals conserved in Seoul Grand Park were examined on the antibody titers of Toxoplasma by the indirect latex agglutination test, 20 out of 131 cases (15.3%) in mammals, 2 out of 75 cases (2.7%) in birds, and none in reptiles, according to species, 15 out of 68 species (22.1%) in mammals, 2 out of 36 species (5.6 %) in birds showed positive antibody titers when the titers of 1 : 32 or higher were regarded as positive. In mammals, it appeared as positive in 2 out of 6 cases (1 out of 3 species) in marsupials, 1 out of 15 cases (1 out of 11 species) in primates, lout of 1 case in bats, 6 out of 13 cases (5 out of 10 species) in carnivores, 1 in 12 cases (1 species out of 3) in odd-toed ungulates, 9 out of 80 cases (6 species out of 38) in even-toed ungulates, and none in rodents and in whales. In birds, 1 out of 21 cases (1 out of 7 species) in gallinaceous birds and lout of 6(5 species) in parrots appeared to have the positive antibody titers of Toxoplasma. And, none of reptiles showed positive. Frequencies of positive antibody titers were high in 1 : 64, 9 cases in mammals, followed by 1 : 32, 6 cases, 1 : 128, 3 cases, and 1 : 256, 2 cases, respectively. Two positive cases in birds appeared to be 1 : 64.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.97-104
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• 2012

Newcastle disease virus (NDV) infects a variety of birds with a wide range of clinical signs from asymptomatic to severe. During a 10-month period in 2011, a total of 1,024 sera from wild birds including 42 species of birds in 8 orders were collected and the seroprevalence of NDV in wild birds was evaluated by hemagglutination inhibition (HI) test. Evidence of NDV infection was observed in 12.6% (129/1,024) of wild birds with a maximum prevalence reported in Mandarin duck (27.8%, 32/115) followed by Mallard duck (20.8%, 57/274), Spot-billed duck (11.9%, 36/303), Pintail (2.9%, 1/34), Black-tailed gull (2.9%, 1/34), White-fronted goose (1.8%, 1/56) and Common teal (1.4%, 1/69). None of the other 35 species of wild birds were antibody-positive for NDV. Mandarin duck, Mallard duck and Spot-billed duck showed high sero-prevalance of 12.2% to 42% during winter season (November to March). Our results indicate that Mandarin duck, Mallard duck and Spot-billed duck might be natural reservoirs for NDV in Korea and the prevalence of NDV infection in wild birds displayed a seasonal pattern with high prevalence of NDV in winter season (November to March).