• 제목/요약/키워드: monsoon

검색결과 494건 처리시간 0.04초

Pollutant Flux Releases During Summer Monsoon Period based on Hydrological Modeling in Two Forested Watersheds, Soyang Lake

  • Kang, S.H.
    • Environmental Engineering Research
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    • 제14권1호
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    • pp.13-18
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    • 2009
  • In this study, specific pollutant releases during the Asian monsoon season were estimated and the information was applied to the non-point pollutant sources management from two forested watersheds of the Soyang Lake. The two watersheds are part of the 2,703 km2 Soyang Lake watershed in the northern region of the Han River. The outlets of the two watersheds were respectively analyzed for continuous water quality concentration and for discharge during various single rainfall events. Statistical power function methods are utilized to compare stream discharge and pollutant flux release during the study period. Based on the monitoring data during the study period, the specific load flux method using simulated discharge was conducted and validated in the two watersheds. The model predictions corresponded well with the measured and calculated pollutant releases. The modeling approach taken in this study was found to be applicable for the two forested watersheds.

농경작지 식생의 군란분류 및 군락생태학적 연구 (Syntaxonomical and synecological Characteristics of Rice Field Vegetation)

  • 김종원;남화경
    • The Korean Journal of Ecology
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    • 제21권3호
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    • pp.203-215
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    • 1998
  • The weed vegetion of the rice fields in south Korea was researched in terms of syntaxonomy and synecology. Total 186 releves were analyzed by the Zurich-Montpellier school's method. 10 syntaxa were recognized: Stellario-Alopecuretum amurensis ass. nov. hoc loco, Alopecuro-Ranunculetum scelerati Miyawaki et Okuda 1972, Hemistepto-Capsellietum bursa-pastoriae ass. nov. hoc loco, Oryza sativa-Echinochloa crusgalli community, Sagittario-Monochorietum plantaginea Miyawaki 1960, Cyperus iria community, Hyperico-Juncetum decipiens ass. nov. hoc. loco, Spirodela-Lemna paucicostata community, Lemno-Salvinetum natans Miyawaki et J. Tuxen 1960. The Oryzo-Echinochloion oryzoides Bolos et Masclans 1955 and the Alopecurion amurensis Miyawaki et Okuda 1972 are representative of the summer annual plant community and the winter annual plant community. It was emphasized that syntaxonomical and synecological study on the ruderal and segetal weed vegetation in Korea should be accomplished in consideration of bioclimatic condition of summer monsoon climate of Korean Peninsula.

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Water Mass Distribution and Seasonal Circulation Northwest of Cheju Island in 1994

  • PANG Ig-Chan;RHO Hong-Kil;LEE Jae-Hak;LIE Heung-Jae
    • 한국수산과학회지
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    • 제29권6호
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    • pp.862-875
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    • 1996
  • The CTD data observed in the sea northwest of Cheju Island have been analyzed to figure out the seasonal circulation around Cheju Island. Warm and saline waters flow into the Yellow Sea through the middle region of the Yellow Sea in winter and along the west coast of Korean Peninsula in summer. On the other hand, cold and less saline waters flow out of the Yellow Sea through the middle region in summer and along the west coast of Korean Peninsula in winter. These flows make the seasonal circulation around Cheju Island. As dynamics, the monsoon wind and the variation of Kuroshio transport have been suggested. Comparing the observational result, the circulation driven by the variation of Kuroshio transport is strengthened by monsoon winds in the numerical model.

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Growth of Wind Waves with Fetch in the Sea of Japan under Winter Monsoon Investigated using Data from Satellite Altimeters and Scatterometer

  • Ebuchi, Naoto
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.31-36
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    • 1998
  • By using wind vectors observed by NSCAT and significant wave heights observed by TOPEX/POSEIDON and ERS-2 altimeters, one-dimensional fetch growth of wind waves Is investigated under conditions of strong wind and high waves of the East Asian winter monsoon. The evolution of fetch-limited wind waves can be observed by the altimeters along the ground tracks. The fetch is estimated by using vector wind field observed by NSCAT. The derived growth characteristics of wind waves are compared with empirical relationships between the non-dimensional fetch and significant wave height proposed by previous studies. Good agreement with the empirical fetch graph formula normalized by the friction velocity is discemible, while the formulas normalized by the wind speed at a height of 10 m tend to underestimate the wave height under such severe conditions of high wind and very long fetch.

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Ozone and Aerosols in the Tibetan Plateau Atmosphere during Asian Summer Monsoon : Balloon-Borne Measurements

  • Y. Iwasaka;Kim, Y.S.;G.Y. Shi;K. Kawahira;T. Shibata;D. Zhang;T. Ohashi;K. Tamura;Y.B. Bai
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2002년도 춘계학술대회 논문집
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    • pp.73-74
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    • 2002
  • Active upwelling air motion in every summer over the Tibetan plateau is an essential process controlling activities of asian summer monsoon which affects water cycle and precipitation in eastern Asia. Large heating rate of surface air on the high plateau with average height of 4000m is considered to cause such large scale upwelling over the plateau. (omitted)

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우리나라 산지 하천의 하안단구는 매 빙기마다 형성되었는가? (Did Fluvial Terrace of Mountain Streams in Korea Form in Each Glacial Stage?)

  • 이광률
    • 한국지형학회지
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    • 제26권3호
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    • pp.19-30
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    • 2019
  • This study summarizes domestic and foreign previous works on fluvial terrace with absolute ages to discuss formative process of climatic terrace in Korea. Different from traditional climatic terrace model, approximately three quarters from foreign works have argued that formation of climatic terrace can be attributed to medium- and short-term climatic change or other environmental factors, rather than long-term climatic change of glacial and interglacial cycles. Based on previous works on fluvial terrace in Korea, it can be suggested that fluvial terrace in Korea formed not due to long-term climatic change of 100,000-year cycles related to glacial and interglacial cycles, but due to medium- and short-term climatic change or climatic event of tens of thousands of years related to intensity change in summer monsoon, one of the important factors affecting precipitation in Korea.

Evolution of a Productive Bivoltine Hybrid of Silkworm Bombyx mori L.(SD7${\times}$SD12) with Shorter Larval Duration

  • Rao, P.Sudhakara;Basavaraja, H.K.;Kalpana, G.V.;Naik, V.Nishitha;Mahalingappa, K.C.;Pallavi, S.N.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제8권1호
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    • pp.27-32
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    • 2004
  • With an objective of evolving quantitatively and qualitatively superior bivolitine silkworm hybrid of Bombyxmori L. for tropics with shorter larval duration without compromising on productivity traits, a breeding programme was initiated at this institute during 1997 by utilizing breeding resource material from the institutes Germplasm collection. The breed SD7 is characterized with plain larvae spinning white oval cocoons and SD12 is characterized by sex-limited larval markings spinning white dumb-bell cocoons. After fixation, these breeds along with other newly evolved breeds were subjected for hybrid evaluation in the laboratory. Based on the hybrid studies, the hybrid SD7${\times}$SD12 was selected and evaluated for one year comprising three major sea- sons (6 trials) of tropics viz., Pre-monsoon (characterized by high temperature, low humidity and without any rain fall), Monsoon (characterized by moderate temperature, heavy rain fall with high humidity) and post-monsoon season (characterized by low temperature and low humidity with frequent rain fall) to know the fluctuations in the larval duration. The evaluation studies indicated that the hybrid is having shorter larval duration with productive merits. The hybrid SD7${\times}$SD12 recorded survival percent of 92.74, shell weight of 46.7 cg, shell ratio % of 24.0 and filament length of 1,200 meters with a shorter larval duration of 24 hrs; when compared to productive hybrid CSR2${\times}$CSR5(control). The breeding methodologies and hybrids usefulness for tropics were discussed.