• Title/Summary/Keyword: NUMBER OF INDIVIDUALS

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Morphological and Molecular Identification of Two Macrourid Species (Gadiformes) Collected by the Korean Observer from the Southern Ocean (남극해에서 한국 옵서버에 의해 채집된 민태과(대구목) 어류 2종의 형태 및 분자동정)

  • Seo, Min-Ju;Kim, Jin-Koo;Chung, Sangdeok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.6
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    • pp.967-972
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    • 2022
  • We investigated the molecular and morphological traits of 338 individual macrourids collected from the Southern Ocean (FAO area number, 88.1 and 88.3) between 2021 and 2022 by Korean bottom trawls. We first identified them as Macrourus caml and Macrourus whitsoni based on morphological traits, such as the number of pelvic fin rays (PF) and the rows of lower jaw teeth (LJT). However four individuals showed uncategorizable morphological characteristics such as PF and LJT numbers that overlapped between the two species. Subsequently, we obtained and analyzed 509 bp of the mtDNA COI sequences of 49 individuals, including the four unidentified individuals, and found only one single nucleotide polymorphism (SNP) that distinguished the two species. Finally, using our molecular identification key, we confirmed that each two individuals were misidentified as M. whitsoni and M. caml reversely. Our results suggest that the number of PF and LJT should be investigated together to accurately identify the two species.

Comparison of fishing gears and catches by areas in the Gape net with wings in Jeonnam, Korea (전남지역 낭장망의 어구 및 어획물 비교)

  • Cho, Sam-Kwang;Song, Dae-Ho;Yoo, Joon-Taek;Choi, Mun-Seong;Cha, Bong-Jin
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.50 no.3
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    • pp.301-309
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    • 2014
  • This study was carried out to compare the regional fishing gears and catches of the gape net with wings used in Jeonnam, Korea. The total length of the gear used in Yeosu, Wando and Jindo was 107.0m, 64.0m, 52.8m, and the size of codend was 4.3mm. 7.8mm. 9.8mm, respectively. The total number of bycatch species from anchovy (Engraulis japonicus) catches in Yeosu, Wando, and Jindo during the survey period were 21, 13, and 13 species. A total of individuals of anchovy accounted for over 90% out of total catches in all survey areas. The proportion of anchovy individuals was constantly high up to October in Yeosu, but it showed a sharp reduction to 18% in October in Wando with the increase of the individuals of Kammal thryssa (Thryssa kammalensis) and Big eyed herring (Sardinella zunasi). In Jindo, individuals of anchovy occupied over 99.8% out of total catches up to August. Since August, the number of individuals of Big eyed herring (Sardinella zunasi), Kammal thryssa (Thryssa kammalensis), and Slimy (Leiognathus nuchalis) has increased while the number of anchovy individuals were decreased.

A Current Status of Natural Heritage Using the Bird's Carcasses in South Korea (국내 천연기념물 멸실신고로 본 자연유산 현황)

  • Lee, Sung-Kyung;Shin, Yong-Un
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.39 no.2
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    • pp.50-54
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    • 2021
  • This study was conducted to investigate the status of carcasses of wild birds among natural monuments in Korea. In Korea, from 2016 to 2020, a total of 38 species and 5,036 individual carcasses of natural monuments were found. The year 2020 saw the highest numbers of species death with 34 and in 2019 the highest number was recorded with 1,095 individuals. In autumn, the largest number of species and the smallest number of individuals were confirmed dead. On the contrary, the smallest number of species and the highest number of individuals were confirmed dead in summer. The largest number of species died in November, and the largest number of individuals died in June. Kestrels accounted for about 20% of the total carcasses, making up the largest number, followed by eagle owls, brown hawk-owls, scops owls, goshawk, eagles and sparrow hawks. In spring and summer, domestic breeding species accounted for most of the carcasses and in winter, the proportion of overwintering individuals such as wooper swans and eagles increased. Reports of lost natural monuments are done by human and the status of the carcasses alone cannot inform the population characteristics of natural monuments when they stay in Korea. However, it is expected that the identified domestic population of strigiformes which has not been investigated in detail because they are nocturnal, and data on the status of carcasses of natural monuments in Korea will provide basic data for the protection of natural monuments.

Seasonal Distribution of Larval Fishes in the Central and Southern Surface Waters of the East Sea (동해 중남부 해역 표층에서 출현하는 자치어의 계절분포)

  • Huh, Sung-Hoi;Choi, Hee Chan;Baeck, Gun Wook;Kim, Ha Won;Park, Joo Myun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.2
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    • pp.216-222
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    • 2013
  • The seasonal distribution and abundance of larval fishes in the central and southern surface waters of the East Sea were investigated seasonally during 2011 and 2012. During the study period, the larvae of 39 species belonging to 26 families were collected. The most abundant species were Engraulisjaponicus, which accounted for 97.5% of the total number of individuals collected. Scomber japonicus, Clupea pallasii, Chromis notatus, Cottidae sp., and Coryphaena hippurus accounted for 1.7% of the total. The number of species, number of individuals, and species diversity indices fluctuated with the season. The peak number of species and individuals occurred in September and May, respectively. The larvae of the main species displayed a distinct spatial distribution and seasonal occurrence patterns. E. japonicus and C. notatus widely distributed throughout the study area. During summer and autumn, S. japonicus and C. hippurus were abundant in southern and offshore regions. C. pallasii occurred only in the southern region during winter. The seasonal occurrence and patterns of distribution of the larvae of main species seems were correlated with surface water temperature.

Herpetofauna and habitat characteristics of 16 lagoons along the eastern coastline of South Korea

  • Lee, Jung-Hyun;Park, Dae-Sik;Lee, Heon-Joo;Kim, Ja-Kyeong;Ra, Nam-Yong
    • Journal of Ecology and Environment
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    • v.33 no.3
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    • pp.229-236
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    • 2010
  • We conducted field surveys of amphibians and reptiles over a two-year period in 16 lagoons along the eastern coastline of South Korea, and determined the habitat characteristics correlated with the number of amphibian and reptilian species and individuals. We documented 11 amphibian species and 8 reptilian species. The dominant amphibian species was the black-spotted pond frog (Rana nigromaculata), and the dominant reptilian species was the red-eared turtle (Trachemys scripta elegans), an invasive species. Among the 14 habitat characteristics, connectivity to mountainous area significantly affected the number of amphibian and reptilian individuals. Other factors, including emerged plant cover, salinity, pH, the number of birds for amphibians and connectivity to agricultural land, lagoon perimeter length for reptiles also influenced the number of species or individuals of them. Our results demonstrate that these lagoons are home to more amphibians and reptiles than has been previously known. To effectively conserve herpetofauna in the lagoon ecosystem, lagoons as well as surrounding wetlands, grasslands, and mountainous areas should be protected.

A study of the spatio-temporal distribution changes of the Korean Hawk Moth (Lepidoptera: Sphingidae)

  • Han, Yong-Gu;Cho, Youngho;Kwon, Ohseok;Kang, Young-Kook;Park, Young-Jun;Kim, Youngjin;Choi, Min-Joo;Nam, Sang-Ho
    • Journal of Ecology and Environment
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    • v.38 no.1
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    • pp.25-38
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    • 2015
  • This study was conducted in an effort to identify the fluctuation of species according to space and time by collecting information on samples of Korean Sphingid moths housed in Korea. The number of Sphingidae moth species housed in Korea was found to be 53. As 48 species and 47 species were found in Gyeongsangnam-do and Gangwon-do, respectively, relatively diverse species were considered to be distributed in these areas. Comparatively, in Jeollabuk-do only 36 species were found, whereas in Chungcheongbuk-do and Jeju Island 39 species were found. The number of individual Sphingid moths surveyed in Korea was 21,414. With regard to the number of individuals per species, Ampelophaga rubiginosa was highest, at 2,483, followed by Theretra japonica (1,716), Callambulyx tatarinovii (1,457), Acosmeryx naga (1,340), Rhagastis mongoliana (1,191), Marumba sperchius (1,083), and Dolbina tancrei (1,072). By region, the largest number of individuals was surveyed in Gyeongsangnam-do (4,595), followed in order by Gangwon-do (3,648 individuals), Gyeonggi-do (3,011), Jeollanam-do (2,454), and Jeju Island (2,382). Over time, the highest numbers-in this case 9,498 individuals in 52 species-were identified after 2000. In the 1990s, there were 6,027 of 49 species identified; in 1980s, 4,332 individuals of 49 species were identified; and, in the 1970s, 937 individuals of 45 species were identified. It was confirmed that more species and individuals were identified as time passed. The appearance of Sphingid moths by month was found to be as relatively diverse, as they appeared from February to November. Overall, southern species, including M. saishiuana, Cephonodes hylas, Acosmeryx castanea, T. nessus, and T. clotho, which mainly inhabit Jeju Island and the southern part of Korea, have increased over time from the past to the present. Species inhabiting the middle or northern parts of the Korean Peninsula or the entire country of Korea, including Sphingulus mus, Ambulyx schauffelbergeri, and Mimas christophi, show decreases over time.

Study on Minimum Viable Population of Seed Bank in Pine Forest (소나무림 매토종자 최소생존가능개체군에 관한 연구)

  • Yi, Myung-Hoon
    • Korean Journal of Environment and Ecology
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    • v.32 no.5
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    • pp.497-506
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    • 2018
  • The purpose of this study was to investigate the proper minimum viable population of a seed bank for the ecological restoration of pine forest using a seed bank. It examined the germinated soil seed bank from August 2010 to November 2011. The results of the correlation analysis showed that the area and the number of herbaceous species were the highest at 0.686. The results of the regression analysis of four variables including the number of woody species, the number of woody individuals, the number of herbaceous species, and the number of herbaceous individuals using the theory of island biogeography to the minimum viable population in studied plots showed that all four variables were significant with area at the level of 0.05, and R square was 0.583. One function was selected between the number of species and the number of individuals from the canonical correlation analysis, and the function square was 0.824. Both canonical function and squared canonical correlation showed significant at the level of 0.01. The result of study recommended the area size of the minimum viable population in pine forest applied by seed bank to be larger than $64m^2$, the number of species to be over 21, and the number of population to be over 120. It also found that the number of herbaceous species determined the cluster size of the seed bank. Therefore, it is necessary to consider herbaceous species that appear in the seed bank.

Biodiversity of Macrofauna at Subtidal Rocky Shore Around Uljin, Korea (울진 조하대 경성암반 해역 대형무척추동물의 생물다양성)

  • Lee, Jae Ho;Hwang, Kang Seok;Rho, Hyun Soo;Choi, Chang Geun
    • Journal of Marine Life Science
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    • v.1 no.1
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    • pp.31-40
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    • 2016
  • Macrofauna and community structure were investigated seasonally at five sites in subtidal zone of Uljin on the east coast of Korea from March 2010 to February 2013. A total of 146 species were collected and identified, including 67 molluscs, 27 arthropods, and 8,688 individuals, including 6,468 arthropods, 1,098 molluscs and 584 echinoderms. In the seasonal investigation, summer has been the highest in 96 species and 2,525 number of individuals. Site 4 was the highest species but number of individuals were the lowest (81 species with 1,377 number of individuals), whereas site 3 was the lowest species and number of individuals were the highest (45 Species with 2,213 number of individuals). These result indicate that Balanus species affected to richness and the other side a gastropod influence by diversity and evenness. And site 3 seems to be good habitate environment for Balanus as the result of 83.4% of Balanus rather than other sites.

Control of Beet Armyworm, Spodoptera exigua Hubner (Lepidoptera : Noctuidae), using Synthetic Sex Pheromone I. Control by Mass Trapping in Allium fistulosum Field (합성 성훼로몬에 의한 파밤나방(Spodoptera exigua)의 방제 I. 외대파에서의 대량유살에 의한 방제)

  • 박종대;고현관
    • Korean journal of applied entomology
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    • v.31 no.1
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    • pp.45-49
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    • 1992
  • Studies were conducted to control Spodoptera exigua in Allium fistulosum field using synthetic sex pheromone trap. Heavily, medium and lightly damagd fields at early transplanting time showed no differences in control effects after 8 weeks of establishment of pheromone traps in Allium fistulosum fields. Number of damaged leaves in each treated field was 0.2-3 individuals per 60 hills comparing with 33.2 individuals at non-treated field. Also, the numbers uf male adults attracted to pheromone traps were 1.8-5.0 individuals at the big inning of installation but increased to 25.8, 49.9, 74.9, and 77.4 individuals after 2, 4, 6, and 8 weeks, respectively. There was a negative correlation between amount of male adults attracted to pheromone traps and number of damaged leaves (r=-0.9572*). Number of adults attracted to various colored light trap for 30 days were 6 in red, 11 in white and none in blue comparing with 1,041 individuals in pheromone trap.

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ESTIMATING THE NUMBER OF ICU PATIENTS OF COVID-19 BY USING A SIMPLE MATHEMATICAL MODEL

  • Hyojung Lee;Giphil Cho
    • East Asian mathematical journal
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    • v.40 no.1
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    • pp.119-125
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    • 2024
  • Predicting the number of ICU patients holds significant importance, serving as a critical aspect in efficiently allocating resources, ensuring high-quality care for critically ill individuals, and implementing effective public health strategies to mitigate the impact of diseases. This research focuses on estimating ICU patient numbers through the development of a simple mathematical model. Utilizing data on confirmed COVID-19 cases and deaths, this model becomes a valuable tool for predicting and managing ICU resource requirements during the ongoing pandemic. By incorporating historical data on infected individuals and fatalities from previous weeks, we establish a straightforward equation. We found the substantial impact of the delay in infected individuals, particularly those occurring more than five weeks earlier, on the accuracy of ICU predictions. Proactively preparing for potential surges in severe cases becomes feasible by forecasting the demand for intensive care beds, ultimately improving patient outcomes and preventing excessive strain on medical facilities.