• Title/Summary/Keyword: migratory high

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Relations NOAA/AVHRR SST between Migratory Fishes in the Korean Seas (NOAA/AVHRR SST 자료를 이용한 한반도 주변해역에서의 수온과 어장변화특성 연구)

  • Seo, Won-Chan;Yoon, Hong-Joo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.12
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    • pp.2265-2270
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    • 2008
  • It was studied to the displacement and the amount of catch for migratory fishes with NOAA/AVHRR SST(Sea Surface Temperature) from 1988 to 2000 in the Korean Seas. The analyzed results from SST data showed generally the oceanic warming trend in the Korean Seas. On the increasement of SST, the distributed areas of migratory fishes which living in the warm waters were displaced gradually to the northward directions(high latitude) and then the amount of catch was increased during this studied periods against to migratory fishes which living in the cold waters.

Phylogenic Analysis of Locusta migratoria (Orthoptera: Acridae) in Haenam-gun and Muan-gun, Jeollanam-do, Korea Using Mitochondrial NADH dehydrogenase subunits (전라남도 해남과 무안의 풀무치 개체군에 대한 마이토콘드리아 NADH dehydrogenase subunit 들을 이용한 계통분석)

  • Lee, Gwan Seok;Kim, Young Ha;Jung, Jin Kyo;Koh, Young Ho
    • Korean journal of applied entomology
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    • v.56 no.4
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    • pp.371-376
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    • 2017
  • In a nationwide survey of the occurrence and density of the migratory locust (Locusta migratoria), high density was continuously observed in the reclaimed areas of Mangun-myeon in Muan-gun, Jeollanam-do, and Sanye-myeon in Haenam-gun, Jeollanam-do, Korea. We have analyzed the nucleotide sequences of NADH dehydrogenase subunit (NAD) 2, NAD4, and NAD5 genes in order to determine the origins of the migratory locusts at two sites. According to the analysis, the migratory locusts in Haenam-gun were closely related with those in Liaoning Province and Heilongjiang Province in the northeast China. In contrast, the migratory locusts in Muan-gun were most similar to those in Japan. Because Korean migratory locusts were not included in the previous global study on the evolution and migration of migratory locusts, we did not know the origin of Korean migratory locusts, earlier. Phylogenetic analyses this study suggested that the migratory locusts from the northeast Chinese population might have migrated and settled in Haenam-gun in Korea. Moreover, another northeast Chinese population might have migrated to Muan-gun in Korea though Sakhalin, Russia and Hokkaido, Japan. However, the possibility that the migratory locusts moved from northeast China might be isolated from each other in Korea, and that the Muan population might migrate to Japan cannot be excluded.

Discovery of Endocotyle incana and Spelotrema pseudogonotyla (Digenea: Microphallidae) from Scolopacid Migratory Birds in Korea

  • Yoo, Ho-Jin;Chung, Ok-Sik;Seo, Min
    • Parasites, Hosts and Diseases
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    • v.50 no.3
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    • pp.273-276
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    • 2012
  • Migratory birds have been suspected as playing a central role in transmission of various trematodes, but few surveys have been undertaken in the Republic of Korea. In the present study, we describe new fauna of microphallid flukes in Korea. Two species of microphallids were found in the intestines of 2 migratory bird species, namely the red necked stints (Calidris ruficollis) and the terek sandpiper (Xenus cinereus), in a coastal area of Gunsan-si, Jeollabuk-do. The microphallids recovered from the latter were 451 ${\mu}m$ in length and 217 ${\mu}m$ in width, and the eggs were very small, 13 ${\mu}m$ by 8 ${\mu}m$. They had the characteristic extracecal vitellaria intruding into the median posttesticular area, belonging to Endocotyle incana. Another microphallids were discovered from both migratory birds, 417 ${\mu}m$ in length and 249 ${\mu}m$ in width. The cirrus was projecting into the genital atrium in form of male papilla, and bounded by a muscular flap, termed pseudogonotyl. They were identified as Spelotrema pseudogonotyla in consideration of the distinctive male papilla and pseudogonotyl. Besides these flukes, Maritrema obstipum and Gynaecotyla squatarolae also were recovered. This paper is in fact the first report on the presence of Spelotrema and Endocotyle in Korea.

Assessment of Ascending Capacity of Migratory Fish in Fishways by Eco-hydraulic Experiments (II) (어도 생태수리실험에 의한 회유성 어류의 소상능력 평가(II) - 계단식 어도 -)

  • Park, Sang-Deok
    • Journal of Korea Water Resources Association
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    • v.34 no.4
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    • pp.381-390
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    • 2001
  • This is to evaluate the ascending capacity of migratory fish in the pool and weir type fishways. Ascending environment of the migratory fish in rivers is analyzed through eco-hydraulic experiments using sweetfish, Plecoglossus altivelis, trout, Oncorhnchus mykiss, and surveying the fall height of existing pool and weir type fishways. When the fall height is less than 16.0cm, the ascending capacity of sweetfish in the pool and weir type fishways is greater than trout. On the other hand when the fall height is over 20.0 cm, the ascending capacity of trout is greater than sweetfish. A sweetfish may prefer to jump for upward moving than trout. And its endurance after upward jumping over wear is greater than that of sweetfish. Because of high fall height of existing pool and weir type fishways the migratory environment in rivers is so poor. When the pool and weir type fishways are designed and constructed in river the fall height of weir must be considered for the variety of migratory fish living in river and the fall height of weir less than 20.0cm is suggested.

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An Analysis of the Change of the Plan Composition in High School through the Checking of Present Use of Migratory Class by Level (수준별 이동식 수업에 따른 고등학교의 평면구성 변화에 대한 분석)

  • Rieu, Ho-Seoup;Ha, Seung-Min
    • Journal of the Korean Institute of Educational Facilities
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    • v.16 no.3
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    • pp.41-48
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    • 2009
  • The purpose of this research is to find out the problem of plan composition by use the school building. The research was performed through the checking of 13 high schools which were built after 1997 in Busan. Followings are the result of the research. Presently, all the schools are divided classes into different levels and teach students, however, it is only limited to English and Mathematics and being carried on mostly for 1st graders. Moreover, although the plan is composed Department System plan which intended to ues new various learning method, schools have changed their plan into Usual with Variation type which is old educational program and renovated a few classes for certain subjects. Due to above reasons, the new kinds of space for Department System plan is used only as a study room by reform or even not used at all. Therefore, improvement of those problems are significant in schools.

Infections with Digenetic Trematode Metacercariae in Freshwater Fishes from Two Visiting Sites of Migratory Birds in Gyeongsangnam-do, Republic of Korea

  • Sohn, Woon-Mok;Na, Byoung-Kuk
    • Parasites, Hosts and Diseases
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    • v.57 no.3
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    • pp.273-281
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    • 2019
  • The infection status of digenetic trematode metacercariae (DTM) was investigated in fishes from 2 representative visiting sites of migratory birds in Gyeongsangnam-do, the Republic of Korea (Korea). A totaly 220 freshwater fishes (7 species) were collected from Junam-jeosuji (reservoir), and 127 fishes (7 species) were also collected from Woopo-neup (swamp) in June and October 2017. As the control group, total 312 fish (22 spp.) from Yangcheon in Sancheong-gun, Gyeongsangnam-do were also collected in June and October 2017. All fishes collected in 3 sites were examined with the artificial digestion method. In the fishes from Junam-jeosuji, more than 4 species, i.e., Clonorchis sinensis, Echinostoma spp., Diplostomum spp. and Cyathocotyle orientalis, of DTM were detected and their endemicy was very low, 0.70. More than 6 species, i.e., C. sinensis, Echinostoma spp., Metorchis orientalis, Clinostomum complanatum, Diplostomum spp. and C. orientalis, of DTM were found in the fishes from Woopo-neup, and their endemicy was low, 5.16. In the fishes from Yangcheon, more than 8 species, i.e., C. sinensis, Metagonimus spp., Centrocestus armatus, C. complanatum, C. orientalis, M. orientalis, Echinostoma spp., and Diplostomum spp., of DTM were detected, and their endemicity was relatively high, 95.48. The percentages of avian trematode metacercariae (ATM) were 99.6% and 94.7% in fishes from Junam-jeosuji and Woopo-neup whereas it was 74.1% in the control site, Yangcheon. The above findings suggested that migratory birds partly affect in endemicity of DTM in the fish in the 2 visiting sites in Gyeongsangnam-do, Korea.

Ecotourism Study on the Chunsuman Bay Birdwatching Festival (생태문화관광 축제연구 : 천수만 철새 축제 사례)

  • Roh Yong-Ho;Jeong Gang-Hoan;Yhang Wii-Joo
    • Journal of Environmental Science International
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    • v.14 no.3
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    • pp.259-264
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    • 2005
  • The purposes of this study were to investigate visitors' environmental attitudes of educational tourism, environmental preservation, and regional economic benefits satisfaction through the Chunsuman Bay Birdwatching Festival. The results of this study were as follows: First, the degree of educational satisfaction was high and this festival provided environmental preservation mind for visitors and local residents as well. The festival participants had a positive attitude toward migratory birds. Especially, the residents who had negative perceptions toward migratory birds due to physical harms of agricultural crops was positively changed after visiting this festival. So there should be prepared for more strategic approaches for residents' visiting and participating this birdwatching festival. Second, while the number of tourists was increased, it did not make a practical contribution to residents' income Particularly, farmers' satisfaction was low. So there should be more strategic programs to improve residents' economic rewards for sustainable development.

Cluster Analysis of the 1000-hPa Height Field around the Korean Peninsula (한반도 주변 1000-hPa 고도장의 군집분석)

  • Jeong, Young-Kun
    • Journal of the Korean earth science society
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    • v.33 no.4
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    • pp.337-349
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    • 2012
  • In this study, we classify the 1000 hPa geopotential height fields around the Korean peninsula through the Kmeans cluster analysis and investigate the occurrence characteristics of each cluster pattern. The 11 clusters are identified as the typical pressure patterns, applying the pattern correlation as a similarity among clusters and the criterion of cluster similarity 0.8, of which three pressure patterns are associated with the extension of Siberia air mass, other three with the latitudes of the longest symmetry axis of North Pacific highs, two with the trough largely under the air mass of Siberia or North Pacific, and the remaining three, the migratory high patterns generally occurring in spring and autumn, are disjointed according to the direction of the longest symmetry axis of highs. The occurrence rate of air masses affecting the Korean peninsula, estimated from the number of occurrence days of 11 pressure patterns, is 55.4% Siberian, 29.3% North Pacific, 12.8% Yangtze-River, 2.5% Okhotsk sea and 68.2% of all these is the continental air masses. The wintertime pressure patterns around the Korean peninsula are nearly contrary to those in summertime, each dominated by the highs extended from the stationary air masses over the Central Siberia and the North Pacific ocean. The migratory highs occur largely in spring and autumn while transferring from the wintertime patterns to summertime patterns, or vice versa. Recently, the occurrence frequency of the highs extended from the North Pacific is on the decrease and while the wintertime pressure patterns occur frequently in spring and autumn, the occurrence frequency of the pressure patterns with trough is on the increase and the migratory highs occur in nearly all seasons.

Meteorological Characteristics related to the Variation in Ozone Concentrations before, during, and after the Typhoon Period in the Korean Peninsula (한반도 태풍영향 전·중·후 시기동안 오존농도 변화에 관한 기상특성 분석)

  • Shin, Hyeonjin;Song, Sang-Keun
    • Journal of Environmental Science International
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    • v.26 no.5
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    • pp.621-638
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    • 2017
  • Meteorological characteristics related to variations in ozone ($O_3$) concentrations in the Korean peninsula before, during, and after Typhoon Talas (1112) were analyzed using both observation data and numerical modeling. This case study takes into account a high $O_3$ episode (e.g., a daily maximum of ${\geq}90ppb$) without rainfall. Before the typhoon period, high $O_3$ concentrations in the study areas (e.g., Daejeon, Daegu, and Busan) resulted from the combined effects of stable atmospheric conditions with high temperature under a migratory anticyclone (including subsiding air), and wind convergence due to a change in direction caused by the typhoon. The $O_3$ concentrations during the typhoon period decreased around the study area due to very weak photochemical activity under increased cloud cover and active vertical dispersion under a low pressure system. However, the maximum $O_3$ concentrations during this period were somewhat high (similar to those in the normal period extraneous to the typhoon), possibly because of the relatively slow photochemical loss of $O_3$ by a $H_2O+O(^1D)$ reaction resulting from the low air temperature and low relative humidity. The lowest $O_3$ concentrations during the typhoon period were relatively high compared to the period before and after the typhoon, mainly due to the transport effect resulting from the strong nocturnal winds caused by the typhoon. In addition, the $O_3$ increase observed at night in Daegu and Busan was primarily caused by local wind conditions (e.g., mountain winds) and atmospheric stagnation in the wind convergence zone around inland mountains and valleys.

Relationship between Migratory Timing of Salmon (Oncorhynchus keta) into the Wangpi River and Coastal Environment of the Mid-eastern Coastal Water of Korea (동해 중부 연안에서 연어(Oncorhynchus keta)가 왕피천으로 이동하는 시기와 연안 환경간의 관계)

  • Kim, Beom-Sik;Jung, Yong-Woo;Jung, Hae-Kun;Lee, Chung Il
    • Journal of Environmental Science International
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    • v.30 no.12
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    • pp.1067-1079
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    • 2021
  • The coastal water is a space where salmon (Oncorhynchus keta), critical energy-conveying mediator, stay to adapt to different environments while traveling between ocean and river ecosystems for spawning and growth. The mid-eastern coast of Korea (MECW) is the southern limit of salmon distributed in the North Pacific Ocean. Understanding the distribution and migration characteristics of salmon in the MECW is important for the prediction of changes in the amount and distribution of salmon related to changes in the future marine environment. We analyzed the relationship between the salmon migratory timing ascending the Wangpi river and change in vertical seawater temperature and tidal elevation. Overall results highlight that (1) Salmon began to ascend the river when the sea surface water temperature (SST) decreased below 20℃; (2) The number of salmon ascending the river increased when the temperature difference between the upper and lower layers decreased, but decreased when the temperature difference was higher than 5℃; (3) The number of salmon ascending the river peaked, when the SST was 18℃-19℃ and sea levels rose at high tide. This study provide important insight into predicting changes in the ecosystem energy circulation through climate change at its southern distribution limit.