• Title/Summary/Keyword: Seasonal appearance

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Inhabitant and Appearance of Finless Porpoise (Neophocaena asiaeorientalis) in the Coastal Wido, Korea (한국 위도 주변해역 상괭이 (Neophocaena asiaeorientalis)의 출현과 서식생물)

  • Lee, Yoo-Won;Choi, Youn;Lee, Heung Heon;Hwang, Bo-Kyu
    • Journal of Fisheries and Marine Sciences Education
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    • v.26 no.3
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    • pp.578-586
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    • 2014
  • The seasonal appearance and distribution of finless porpoise (Neophocaena asiaeorientalis) was investigated with sighting survey method around Wido in West sea, Korea. Fishing survey with drag net was also conducted to investigate the species composition of inhabitants and the consignment quantity data of fisheries cooperation was collected to confirm the seasonal change of the composition and quantity of them. Finless porpoise didn't emerged around Wido in winter season, but the number of appearance in summer season amounted to 1~15 indv. for 15 observing points and the appearance frequency became lower in open sea than in inshore. There was also significant relationship between the appearances of finless porpoise (Neophocaena asiaeorientalis) and that of inhabitants. we consequently concluded that finless porpoise typically distributes from April to september, and moves to another area for wintering and food consumption from October to March.

The fishing grounds and frequency of appearance of Chinese fishing vessels obtained by analyzing AIS data in the south coast of Jeju Island (AIS data 분석에 의한 제주도 남해안에서의 중국 어선들의 조업어장과 출현빈도)

  • KIM, Kwang-il;LEE, Chang-heun;AHN, Jang-young
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.4
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    • pp.356-362
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    • 2019
  • We collected AIS information on fishing vessels operating near Jeju Island, and analyzed appearance density of the Chinese fishing vessels and inferred the movements of the fishing grounds. AIS information was received from October 16, 2016 to October 16, 2017 and stored on a hard disk through a program called AisDecoder. Unauthorized fishing vessels within the Exclusive Fisheries Agreement Zone (EFAZ) operated near the EFAZ boundary, and the frequency of appearance of fishing vessels were high in the middle waters of Korea and Japan, 252 and 250 fishing zones. Chinese fishing vessels authorized to enter appeared scattered outside the Prohibiting Fishing Zone of the Large Trawlers (PFZLT), and the closer they were to the PFZLT boundary, the higher the appearance density. And the appearance of Chinese fishing vessels with a speed from 0 to 3 knots was mostly outside the EFAZ, showing high density in the waters close to the boundary between Korea and Japan. On the other hand, within the EFAZ, the frequency of appearance of Chinese fishing vessels was also low and scattered. The appearance of Chinese fishing vessels with a speed from 3 to 5 knots mostly shows some variability within the EFAZ, but the frequency of appearance was high and the density was high. The seasonal appearance of Chinese fishing vessels in the waters south of Jeju Island appeared in the southwest in the autumn and then moved south and southeast of Jeju Island in the winter, and in the spring and summer. They were considered going to other fishing grounds without fishing in the waters south of Jeju Island.

Distribution Characteristics in the Habitat of Leptalina unicolor Population (은줄팔랑나비 개체군의 서식지 내 분포특성)

  • Hong, Sung-Jin;Yoon, Chun-Sik;Cheong, Seon-Woo
    • Journal of Environmental Science International
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    • v.28 no.12
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    • pp.1123-1131
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    • 2019
  • In this study, we investigated the spatial range, distribution pattern, temporal appearance, sex ratio, seasonal pattern, and size of the population of Leptalina unicolor locally inhabiting the wetland protection area in the Jaeyaksan Mountain. We found that the butterfly was distributed across four areas at 750 m above sea level and in an area of 96,000 ㎡. in the southeastern slope of the mountain. The discontinuous distribution of the butterflies in the meadow. According to our survey conducted from 2012 to 2014, L. unicolor occurred in May (spring) and July (summer) each year, with the male population more than three times higher than that of the female population. The population size estimated using the mark and recapture method on the back of the hind wing in the two years was as follows: 877±502 and 1243±800 individuals in the spring and summer of 2012, respectively, and 783±429 and 506±365 individuals in the spring and summer of 2014, respectively, suggesting no specific seasonal pattern. The findings of this study are expected to be useful for the conservation of the populations and habitats of L. unicolor, which are currently distributed locally due to a decrease in population size.

The seasonal appearance and chemical composition characteristics of cladode of Opuntia humifusa (천년초 줄기의 수확 시기 별 외관 및 성분 품질 특성)

  • Kim, Hee Jung;Kim, Mi-Hyun;Jang, Mi;Lim, Tae-Gyu;Hong, Hee-Do;Rhee, Young Kyoung;Kim, Kyung-Tack;Cho, Chang-Won
    • Food Science and Preservation
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    • v.23 no.4
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    • pp.502-509
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    • 2016
  • The seasonal appearance and the chemical composition characteristics of cladode of Opuntia humifusa were investigated in this study. The minor (horizontal) and major (vertical) axes, the width, and weight of O. humifusa cladode were compared for its appearance features. Moisture, crude protein, ash, fat, color, dietary fiber, mineral, and amino acids contents were measured for the comparison of their chemical composition characteristics. The cladode of O. humifusa harvested in summer showed higher values of minor and major axis, width, and weight than those harvested in winter. According to the results of Hunter color index, cladode of O. humifusa harvested in summer showed the highest lightness level (Hunter L value). In the meanwhile, cladode of O. humifusa harvested in spring showed the highest Hunter a (redness) and b (yellowness) values. Cladode of O. humifusa harvested in summer had the lowest crude protein and crude fat contents, while it showed the highest crude ash content. The total contents of moisture and dietary fiber were significantly greater than summer-harvested cladode of O. humifusa followed by spring- and winter-harvested cladode of O. humifusa. The major mineral content of all seasonal cladode of O. humifusa was $Ca^{2+}$. Glutamic acid and aspartic acid were the major amino acids in all seasonal samples. Contrary, the contents of total amino acids and free amino acids were the lowest in summer-harvested cladode of O. humifusa. Taken together, it was concluded that the appearance and chemical quality of cladode of O. humifusa was versatile depending on the harvesting season.

Species composition of larval fishes in the eastern Jinhae Bay, Korea (진해만 동부해역에 출현하는 자치어의 종조성)

  • KIM, Hyeon Ji;JEONG, Jae Mook;PARK, Jong Hyeok;HUH, Sung-Hoi;BAECK, Gun Wook
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.54 no.1
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    • pp.81-88
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    • 2018
  • A study for species composition and abundance of the fish assemblages in the eastern Jinhae Bay, Korea was conducted using monthly larval collection by a RN80 net from October, 2010 to September, 2011. Of all the 45 species collected, the dominant species were Clupea pallasii, Hexagrammos otakii, Pholis fangi and Engraulis japonicus. Clupea pallasii, Hexagrammos otakii, Pholis fangi in winter and examined Engraulis japonicus, Acanthogobius sp., Parablennius yatabei, and Tridentiger trigonocephalus in summer appeared seasonally. Popoulation characteristic by stations was not clear seasonally and spatially, and appearance aspects of dominant species were similar by stations. Compared our results with other studies in the South Sea, dominant species and their appearance period were similar to their spawning period. Finally, the appearance period of the larvae in the South Sea was closely resulted to spawning period rather than the regional characteristic.

On the Flies Collected from Suseungdae Area, Geochang-gun, Gyeongnam, Korea and Their Seasonal Prevalence (경남 거창군 수승대 일대의 파리류와 계절적인 발생 소장)

  • Jo, Tae-Ho;Jung, Youn-Yong
    • Journal of Environmental Science International
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    • v.17 no.7
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    • pp.719-732
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    • 2008
  • The total number of flies collected was 4,864 with sex ratio of 32.8% from Suseungdae area, Geochang-gun, Gyeongnam, Korea. The fauna of fly was 35 species consisting of 13 Calliphoridae, 12 Muscidae, 8 Sarcophagidae, 1 Dryomyzidae and 1 Anthomyiidae. The number of genus and species of Calliphoridae and Muscidae of Suseungdae area were similarly found in the mountain and residential areas, however, those of Sarcophagidae was similar with that of residential area. Calliphoridae was the most dominant family at the survey sites with 60.4% of the total collected flies, and followed Muscidae 33.3% and Sarcophagidae 6.2%. The dominant species were constituted of 83.6% of the total flies and the order of collected flies was Chrysomyia pinguis (42.2%), Limnophora sp. (10.8%), Muscina angustifrons (8.6%), Calliphora lata (8.1%), Fannia scalaris (5.5%), Lucilia caesar (3.9%), and Boettcherisca peregrina (4.2%). The seasonal prevalence of flies was from the middle of March to the end of November, and the peak time of appearance was the middle of June, middle of September and middle of October. The highest peak of prevalence was the middle of October. The similarity index of the flies was above 80%, compared to Mt. Geonheung and landfill in Geochang-gun. The number of fly species was more affected by the mean air temperature. In the comparison of the seasonal prevalence and relative abundance of 7 predominant species among 35 species, each species was found to exhibit its specific characteristics and showed the pattern of species.

Seasonal Changes of Drosophilidae (Diptera) at the Mt. Soribong in Korea (광릉 소리봉 초파리과의 종구성과 계절적 변동)

  • 김남우
    • The Korean Journal of Ecology
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    • v.22 no.5
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    • pp.311-316
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    • 1999
  • Community organization of the drosophilid flies was investigated with respect to the seasonal variation of the species abundance at the natural forests on Mt. Soribong in Kwang-nung (Kyung-Ki Do, Korea) from May to October 1996. The dominant species were Amiota okadai. Scaptomyza pallida, Hirtodrosophila sexvittata. Drosophila bizonata. D. unispina. and D. brachynephros in the annual collection. A. okadai was found with numerically dominance in April and was found in June with less superiority. S. pallida showed their highest peak in occupational in May and after soon they decreased. There was a remarkable increase in the numbers of H. sexvittata in July. This increase may be coincident with the appearance of fungi which provide a breeding site for this species in the forest. On the other hand, D. biauraria and D. triauraria showed their highest peak in May and after soon they decreased, and in September they made the lower peak again. Four species (D. anguraria. D. brachnephros, D. nigromaculata, D. unispina) of qunaria group were found with dominance in August to September. These results suggest that the predominant species in the forest avoid niche overlap by means of seasonal separation of breeding, which is strongly affected by factors associated with season in the deep wooded forests.

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Seasonal Variation of Zooplankton Communities in the Southern Coastal Waters of Korea (남해 연안 동물플랑크톤 군집의 계절변동)

  • Moon, Seong-Yong;Oh, Hyun-Ju;Soh, Ho-Young
    • Ocean and Polar Research
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    • v.32 no.4
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    • pp.411-426
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    • 2010
  • The seasonal variations in the zooplankton community of the southern coastal waters of Korea were investigated seasonally in May, August, November 2005, and February 2006. A total of 74 taxa were sampled, with an average abundance ranging from 2,426~23,793 indiv./$m^3$, among which Noctiluca scintillans predominated. Noctiluca scintillans, Acartia omorii, Acartia erythraea, Paracalanus parvus s. l., Centropages abdominalis, Tortanus forcipatus, and Pseudevadne tergestina were the most abundant species detected. Zooplankton diversity was high around the inner regions during the summer, but it was relatively low in the stations located in the outer regions in the autumn. Non-metric multidimensional scaling (nMDS) revealed significant differences in the structures of the zooplankton community among the three regions. Our results showed that the seasonal variations in zooplankton communities in the southern coastal waters of Korea were attributable to seasonal changes in temperature, salinity, chlorophyll a concentrations, and N. scintillans blooms; additionally, this particularly study area might have been specifically influenced by the appearance of the Tsushima Warm Current.

Classification of Perennial Ryegrass Varieties by the Dry Weight of Plant per pelative Tiller Appearnce pates ( DW/RTAR ) (상대경수출현율당 개체중에 의한 perennial ryegrass 품종의 분류)

  • 이주삼;김성규
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.11 no.1
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    • pp.6-11
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    • 1991
  • In order to classify the varieties by the characters to evaluating potential winter hardiness was examined using the relationships between autumn growth of seedling plants and the dry weight of plant(DW), and yield components of 1st cutting in 16 varieties of perennial ryegrass grown under individual plant basis.The results are summarized as tollows:1. The dry weight of plant(L)W) was positively correlated with the number of tillers of seedling plants, but negatively correlated with seedling vigors of plants in autumn growth. 2. The dry weight of plant(L)W) indicated positively significant correlations with the dry weight of heading tillers(HDW), number of tillers per plant(NT), number of vegetative tillers(VNT), number of heading tillers(HNT), dry weight of a tiller(WT) and heading rates(HR) of 1st cutting.3. Relative tiller appearance rates(RTAK) corresponded with the seasonal patterns of tillering ability. Thevariety with a low values of relative tiller appearance rates(RTAR) showed vigorous tillering ability inautumn growth, but the variety with a high values of relative tiller appearance rates(KTAR) showedvigorous tillering ability in spring growth.4. The dry weight of plant per relative tiller appearance rates(DW/RTAR) indicated positively significant correlations with the dry weight of plant(DU7, plant length(PL), dry weight of heading tillers(HDW), number of tillers per plant(NT), number of heading tillers(HNrr), dry weight of a tiller(WT) and heading rates(HR) of 1st cutting.5. The varieties were classified into 2 groups by the dry weight of plant per relative tiller appearance rates(DW/RTAR). Thus. Manhattan, P-2, Tonga, Tove, Hella. I'eramo and Fiesta belong to the group of DW/RTAII>l. 0, and Maprima, Caliente, Tempo, Gambit, Magella, Prana. Reveille, Barlet and Bravo belong to the group of DW/RTAR

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