• 제목/요약/키워드: seasonal fluctuations

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도시화에 따른 부산과 대구의 일교차 변화 특성에 관한 연구 (Analysis on Variation of Diurnal Temperature Range of Busan and Daegu according to Urbanization)

  • 박명희;이준수;안지숙;이혜현;한인성;엄기혁;서영상;김해동;배헌균
    • 한국환경과학회지
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    • 제25권2호
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    • pp.295-310
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    • 2016
  • In this study, changes in daily temperature range were investigated using daily maximum and minimum temperatures of Busan and Daegu for last 81 years (1934-2014), and also characteristics of daily temperature range and seasonal fluctuations by urbanization were examined. First, elapsing changes showed a lower decreasing trend in Busan ($0.32^{\circ}C$) than Daegu ($1.28^{\circ}C$) for last 81 years. Daily temperature range showed the highest rise in winter in both Busan and Daegu. Second, daily temperature range due to urbanization showed that Busan had a pronounced decreasing trend before urbanization meanwhile Daegu showed the same trend after urbanization. On seasonal changes, the results of Busan showed a decreasing trend in summer before urbanization, and in autumn after urbanization. For Daegu, the results showed a decreasing trend in spring before urbanization, and in winter after urbanization. Seasonal fluctuations of Busan showed little difference in the pre and post-urbanization, except in winter and summer. There was large difference in daily temperature range in winter after urbanization, and in summer before the urbanization. The results in Daegu showed that there was decreasing trend of daily temperature range in all seasons after urbanization.

한강수질의 월변동성에 관한 연구 (Monthly Fluctuation of the Han River Water Quality)

  • 유호식
    • 한국물환경학회지
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    • 제20권4호
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    • pp.352-356
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    • 2004
  • Variations of water quality parameters were investigated for last 13 years in Han river. Deviation from 3 month moving average was suggested for the variation analysis. Many parameters of mainstream and tributaries showed similar monthly fluctuations. Suspended solid of mainstream showed higher fluctuation than that of tributaries due to summer flood. Contrarily, the organic parameters such as BOD, COD, and TN showed lower fluctuations in the mainstreams. The magnitude of deviation was in the order of pH < DO, COD, temp. < BOD, TN < TP, SS. Strong correlation was found in BOD data of adjacent sites. Main sites showed low deviation in comparison to adjacent common sites of mainstream (1:2.4). Mainstream showed low deviation in comparison to tributaries (1:1.7). Seasonal tendency of monthly BOD was confirmed using autocorrelation function. The deviation was in inverse proportion to the magnitude of BOD.

남산과 광릉의 토양 미소절지동물에 관한 연구 (Soil Microarthropods Fauna at the Namsan and Kwangreung)

  • 박홍현;정철의;이준호;이범영
    • 한국토양동물학회지
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    • 제1권1호
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    • pp.37-47
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    • 1996
  • This research was carried out to investigate soil mictoarthropods fauna in Namsan and Kwangreung which were considered to receive different degreeds of environmental pressures. In basic environmental data, Namsan where under rather accelerated acidification by air contamination and acidic rain showed low pH, tardy decomposition and turnover rate. Population density of soil microarthropods was high in Kwangreung 17,169.8/\ulcorner\ulcorner(coniferous forests), 17,892.6/$\textrm{m}^2$(deciduous forests) than in Namsan, 12,143.8/$\textrm{m}^2$ (coniferous forests), 14,216$\textrm{m}^2$(deciduous forests). Biomass of soil microarthropods was 2,020.219mg/$\textrm{m}^2$ at coniferous forests and 4,270.172mg/$\textrm{m}^2$ at deciduous forests in Namsan, and 3,287.326mg/$\textrm{m}^2$ at coniferous forests and 4326.1mg/$\textrm{m}^2$ at deciduous forests in Kwangreung. Population density constantly showed high in spring, and seasonal fluctuations were correlated with seasonal precipitation. As far as vertical distribution is concerned, population density was concentrated in litter layer as 70% while 30% are in soil layer and also decreased with increasing depth.

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Fluctuations of Coastal Water Temperatures Along Korean and Japanese Coasts in the East Sea

  • KANG Yong-Q.;CHOI Seong-Won
    • 한국수산과학회지
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    • 제21권6호
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    • pp.351-360
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    • 1988
  • Based on historic data of monthly means of sea surface temperatures (SST) for 24 years $(1921\~1944) $ at 23 Korean and Japanese coastal stations in the East Sea (the Japan Sea), we analyzed spatio-temporal characteristics of coastal SST and SST anomalies. The means of SST at Korean coast are higher than those at Japanese coast of the same latitudes, and the annual range of SST at Korean coast are larger than those at Japanese coast. Empirical orthogonal function analysis shows that almost all $(96\%)$ of the SST fluctuations are described by simultaneous seasonal variations. The flurtuations of SST anomalies are small in the Korea Strait and large at the boundaries between the warm and told currents in the basin. The fluctuations of SST anomalies along Korean coast are correlated each other The same is true for SST anomalies along Japanese coast. However, there is only weak correlation between the SST anomalies at Korean coast and those at Japanese coast. Empirical orthogonal function analysis shows that $27\%$ of the coastal SST anomalies in the East Sea are described by simultaneous fluctuations, and $12\%$ of them are described by alternating fluctuations between Korean and Japanese coasts.

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복수의 태풍내습에 의한 해운대 해수욕장 침식변화특성 (Characteristics of Erosion Variation at Haeundae Beach due to Multiple Typhoons)

  • 강태순;이종섭;김종범;김종규
    • 해양환경안전학회지
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    • 제25권7호
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    • pp.920-926
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    • 2019
  • 본 연구에서는 해양수산부 연안침식 실태조사에서 운영 중인 해운대 해수욕장 비디오 모니터링 시스템을 이용하여 연안정비 사업 실시 이후의 백사장 면적변화를 분석하였다. 해운대 해수욕장은 연안정비사업을 통한 대규모 양빈이후 계절변동 특성과 함께 해빈 안정화 과정을 거치면서 잘 유지되었으나, 최근 2년간 복수의 태풍 내습에 의하여 해운대 해수욕장의 계절변동특성 및 해빈안정화 양상은 균형을 상실하였으며, 급격한 침식이 발생하였다. 특히, 2018년 태풍 솔릭, 콩레이에 의해 침식된 백사장은 계절변동에 의한 겨울철 해빈면적을 회복하지 못하였으며, 2019년에 내습한 다수의 태풍들로 인하여 해빈면적이 전년 대비 9.5 %(12,607 ㎡) 감소하였다. 해운대 해빈 전면에서 관측된 파랑자료와 해빈면적자료를 분석한 결과, 계절에 따른 입사파향에 따라 백사장의 서측, 중앙부, 동측의 침퇴적 경향이 뚜렷이 나타났다. 향후에는 계절변동특성의 둔화와 지속적인 침식경향이 나타나는 원인을 파악하기 위해 잠제 시설물의 마루높이, 기능유지 여부 및 잠제 외부로의 모래유출추적 등 보다 정밀한 모니터링이 필요하다.

장봉도 갯벌을 이용하는 어류군집의 계절 변화 (Seasonal Variation of Fish Assemblages on Jangbong Tidal Flat, Incheon, Korea)

  • 서인수;홍재상
    • 한국수산과학회지
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    • 제43권5호
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    • pp.510-520
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    • 2010
  • This study investigated the community structure and seasonal variation of the fish assemblages on Jangbong tidal flat, Incheon, Korea. Fish were collected monthly using a small otter trawl from November 1999 to January 2001. Thirty-six fish species were recorded, with a mean density of 185 individuals and biomass of 2,594.3 gWWt. The most abundant species by number were Johnius grypotus (23.7%), Acanthogobius hasta (17.8%), and Cynoglossus joyneri (10.7%), while the dominant species by catch weight were Acanthogobius hasta (21.2%), Sebastes schlegeli (16.2%), J. grypotus (14.0%), and C. joyneri (10.8%). Cluster analysis and non-metric multi-dimensional scaling (nMDS) were applied to assess the seasonal fluctuation in the fish assemblages. Based on the result of the cluster analysis and nMDS ordination, the faunal group could be divided into cold- and warm-water specialist groups. The cold-water specialists included A. hasta, Acanthogobius luridus, Triaenopogon barbatus, Tridentiger trigonocephalus, and Liza haematocheila. The warm-water specialists were J. grypotus, C. joyneri, S. schlegeli, and Hexagrammos otakii. In conclusion, the community structure showed a distinct seasonal trend, which seemed to be related to the seasonal fluctuations in water temperature.

지리산 피아골 토양 미소절지동물상의 계절적 변화 및 수직분포 (Seasonal Abundance and Vertical Distribution of Soil Microarthropods at the Piagol Mt Chiri)

  • Hong, Yong;Tae-Heung Kim;Young-Chol Oh
    • The Korean Journal of Ecology
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    • 제19권5호
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    • pp.393-402
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    • 1996
  • Density fluctuations of soil microarthropods at the Piagol, Mt. Chiri was assessed on the basis of 113, 096 individuals collected from March 1993 to February 1994. Of 6 classes, and 18 orders, the Arachnida and Insecta were the most numerous members with abundance of 51.4% and 46.3%, respectively. The mean density of the Acari was $13, 310/m^2$ of microarthropods. The Acari were abundant in autumn and less found in winter and the density fluctuation of the Collembola followed a similar trend. The vertical distribution of the mesofauna revealed from the soil samples taken from the surface to 5 and from 5 to 10 cm in depths was as follows. In 5~10 cm layer. Collembola was numerous with abundance of 54.7%, followed by 40.1% fo Acari and the soil microarthropods reached the highest density peak in spring, while the lowest in winter. Populations concentrated in the 0~5 cm layer as much as 62.2% throughtout the season and 82.4% throughtout the altitudes. The Acari / Collembola (A/C) ratio in the 0~5 cm layer was higher than that in the 5~10 cm.

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우리나라 남해안 해수욕장의 미소플라스틱 분포와 조성 (Distribution and Composition of Plastic Pellets and Trashon the Beaches of the Southem Coast at Korea)

  • 김삼곤;김종화;박창두
    • 수산해양교육연구
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    • 제14권1호
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    • pp.43-56
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    • 2002
  • (1) This study was carried out to obtain seasonal fluctuations of marine debris in 5 beaches near the Southern Coast of Korea during May, 1999 - April, 2000. The results are as follows: 1. The density of marine debris was remarkably highest at Namhae beach among 5 beaches. The major part of debris in the beach was styrofoam, with the density of 348.5${ea/km}^2$. But, it was Songjung where the largest amount of resin pellets existed. 2. The composition of styrofoam consisted of 51% of the marine debris, wood& papers was 11%, resin pellets & plastics were 8% and others were 16%. 3. Seasonal fluctuations irregularly change in each beach, but the amount of resin pellets were found to be large only in September. It is estimated that resin pellets are beached upon the coastal beaches by the strong warm currents(Tushima currents) during the summer season. 4. Debris fabrication materials that were found had most of parts made up of PE 71.2%, PP 21.2% and EVA 7.7% through these surveys. 5. In the polluted state, the medium one among the 3 specifications(o1d, medium and new state) occupied 88.5% or so.

서울大 光陽蓮習林內 土壤 微小節肢動物에 관한 硏究 5. 垂直分布와 季節的 變動 (Soil Microarthropods at the Kwangyang Experiment Plantation(5. Vertical Distribution and Seasonal Fluctuation of Soil Microarthropods))

  • Kwak, Joon-Soo;Park, Seong-Sik;Kim, Tae-Heung;Cho, Hyung-Chan
    • The Korean Journal of Ecology
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    • 제13권1호
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    • pp.25-32
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    • 1990
  • The vertical distribution and seasonal fluctuation of soil microarthropods in the forests with different flora were investigated in this study. soil micrarthropods were concentrated as much as 71.8% in the first layer subsoil (0-5cm), 22.3% in the second layer subsoil (5-10cm), and 5.9% in the third layer subsoil (10-15cm) in the decreasing order. The population density in the first layer decreased slightly in winter while that of the second layer increased. However, the density in the first layer bounced back in the following spring. Seasonal fluctuations of population density were revealed "Two peak-Two valley type", that is, the densities were high in fall and spring, and low in winter and summer.nd summer.

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