• 제목/요약/키워드: Bottom water temperature

검색결과 546건 처리시간 0.032초

쌀바구미(Sitophilus oryzae Linne)의 현미함수량에 미치는 영향 (Some effects of rice weevil (Sitophilus oryzae L.) on the moisture contents of polished rice)

  • 현재선
    • 한국응용곤충학회지
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    • 제1권
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    • pp.20-25
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    • 1962
  • 쌀바구미가 현미의 함수량에 미치는 영향을 조사하여 다음과 같은 결과를 얻었다. A. R.H. $75\%\; 28^{\circ}C$에 있어서의 함수량의 증가 1) 100, 200, 500개체의 쌀바구미에 의하여 산란된 집단에 의하여 4주간에 사수량은 무곤충구에 비하여 $0.4\%,\;1\%,\;3.3%\$의 증가가 있었다. 2) 최대함수량은 500개체구에서 4주후에 $16.26\%$, 최소 100개체구에서 $14.86\%$였다. 3) 현미함수량의 증가는 현미내의 쌀바구미의 집단이 클수록 많다. B. $28^{\circ}C$에 있어서의 함수량의 층위적 변동 1) 무곤충구에 있어서는 함수량은 계속하여 감소하며 12주후에 있어서는 $10.66\%,\; 10.65\%,\; 12,21\%$가 되였다. 2) 실험구에 있어서는 상층을 제외하면 함수량은 12주후에는 최초의 함수량보다 증가하였으며 중층이 $15.64\%$, 하층이 $41.55\%$였다. 3) 대조구, 실험구 모두 상층에 갈수록 공중에의 수분탈취가 심하여 함수량은 하층보다 적었다. 4) 현미함수량의 증가는 곤충의 활동 급 미생물의 활동에 의한 것이라고 생각된다. 5) 쌀바구미의 집단은 어펄 특정한 층에 집합하는 일은 없으나 하층의 현미의 변질에 따라 상층으로 이동한다. 6) 현미내 온도는 대조구에 있어서는 환경온도와의 차가 적으며 낮은 것이 보통이나 실험구에 있어서는 높은 것이 보통이며 하층은 상층보다 높았다. 7) (6)에서와 갈은 온도의 차의 원인은 곤충의 호흡열 급 미생물의 분해열이 그 원인이라고 생각된다.

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조류 성장 억제를 위한 녹조 및 적조 발생과 황사의 상관관계 초기적 연구 (An Initiative Study on Relationship between Algal Blooms and Asian Dust for Regulation of Algal Blooms)

  • 김태진;정재칠;서라벌;김형모;김대근;전영신;박순웅;이세윤;박준조;이진하;이재정;이은주
    • KSBB Journal
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    • 제29권4호
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    • pp.285-296
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    • 2014
  • Although the problems of the algal blooms have been world-widely observed in freshwater, estuary, and marine throughout the year, it is not yet certain what are the basic causes of such blooms. Consequently, it is very difficult to predict when and where algal blooms occur. The constituents of the Asian dust are in a good agreement with the elements required for the algal growth, which suggests some possible relationship between the algal blooms and the Asian dust. There have been frequently algal blooms in drinking water from rivers or lakes. However, there is no any algal blooms in upwelling waters where the Asian dust cannot penetrate into the soil due to its relatively weak settling velocity (size of particles, $4.5{\pm}1.5{\mu}m$), which implies the possible close relationship of the Asian dust with algal blooms. The present initiative study is thus intended firstly in Korea to illustrate such a relationship by reviewing typical previous studies along with 12 years of weekly iron profiles (2001~2012) and two slant culture experiments with the dissolved Asian dust. The result showed bacterial suspected colonies in the slant culture experiment that are qualitatively in a good agreement with the recent Japanese studies. Since the diatoms require cheap energy (8%) compared to other phytoplankton (100%) to synthesize their cell walls by silicate, the present results can be used to predict algal blooms by diatoms if the concentrations of iron and silicate are available during spring and fall. It can be postulated that the algal blooms occur only if the environmental factors such as light, nutrients, calm water surface layer, temperature, and pH are simultaneously satisfied with the requirements of the micronutrients of mineral ions supplied by the Asian dust as enzymatic cofactors for the rapid bio-synthesis of the macromolecules during algal blooms. Simple eco-friendly methods to regulate the algal blooms are suggested for the initial stage of blooming with limited area: 1) to cover up the water surface with black curtain and inhibit photosynthesis during the day time, 2) to blow air (20.9%) or pure oxygen into the bottom of the water and inhibit rubisco for carbon uptake and nitrate reductase for nitrogen uptake activities in algal growth during the night, 3) to eliminate the resting spores or cysts by suction of bottom sediments as deep as 5 cm to prevent the next year germinations.

경북지방의 뽕밭에 발생한 발아불량현상의 원인 및 방제에 관한 연구 (Studies on the Cause and Control for Non-Sprouting in the Mulberry Field of Kyung-pook Province)

  • 유근섭;김규래;김낙상
    • 한국잠사곤충학회지
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    • 제28권2호
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    • pp.1-8
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    • 1986
  • 1983년 춘기 경북 중북부지방의 뽕밭에 원인불명의 발아불량현상이 발생하였던 바, 그 원인을 구명하기 위하여 대표적인 피해뽕밭을 선택 토양 및 식물체를 분석하였으며 피해지역의기온을 조사분석하여 다음과 같은 결론을 얻었다. 1. 피해상의 특징은 전혀 발아를 하지 않고 죽는 것과 발아도중 가지 선단부의 동아가 탈포기까지 피아가 갑자기 말라죽고 피부본부에 Necrosis 현상이 발생하며 심한 경우에는 가지의 기부에 Measles증상이 나타난다. 2. 유효토심은 피해뽕밭이 30cm이내, 건전뽕밭이 30-60cm이었다. 3. 토양 pH, 유기물 합량, 유효인산 및 치환성기 등은 피해뽕밭이나 건전뽕밭간에 차이가 없었다. 4. 토양내 유효붕소함량은 칠곡 및 상주 화서 뽕밭에서만 건전뽕밭이 피해뽕밭보다 유의하게 많았으며 선산 및 상주 낙동 뽕밭에서는 건전뽕밭이 피해뽕밭보다 약간 많았으나 유의차가 없었다. 5. 식물체의 붕소함량은 엽 피부 똑같이 건전뽕밭이 피해뽕밭보다 유의하게 많았다. 6. 발아불량 피해가 심하였던 뽕밭에 붕사를 첨가하여 사경재배한 뽕나무가 붕사나 붕소를 시용한 결과 토양 및 식물체내에 붕소함량이 유의하게 증가하였으며, 거의 100%에 가까운 회복률을 나타냈다. 7. 발아불량 뽕밭에 붕사를 시용한 뽕나무와 붕소를 첨가하여 사경재배한 뽕나무가 붕사나 붕소를 시용하지 않은 뽕나무보다 내동성이 강하게 나타났다. 8. 83년 하순의 이상고온이 예년보다 빨리 뽕나무의 수액을 상승시켰고 이로 인하여 발아유도가 빨랐기 때문에 4월 3일 조상최저기온이 -6.4$^{\circ}C$로 급강하하여 많은 뽕나무가 동해피해를 받았던 것 같다. 이상의 결과로 보아 83년 춘기 경북중북부지방의 뽕밭에 발생한 발아불량현상의 원인은 주인이 저온에 의한 동해라고 볼 수 있으며 지역적으로는 붕소결핍에 의한 발아불량현상도 적지 않았고 특히 붕소결핍이 동해피해를 가속화시켰다고 볼 수 있다.

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아산만 저어류 -III. 정점간 양적 변동과 종조성- (The Demersal Fishes of Asan Bay -III. Spatial Variation In Abundance and Species Composition-)

  • 이태원
    • 한국수산과학회지
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    • 제26권5호
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    • pp.438-445
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    • 1993
  • 1991년 가을에는 1992년 여름 사이 아산만에서 otter trawl로 저어류 자료를 수집하여 저어류의 계절 및 정점간의 군집구조를 분석하였다. 출현한 34종 중, 참서대(Cynoglossus joyneri), 민태(Johnius belengeri), 곤어리(Thrissa koreana) 및 등가시치(Zoarces gillii)가 총 채집개체수의 $93\%$를 차지하였다. 위의 4종 중 부어류인 곤어리를 제외한 우점 3종은 저질이 세립질인 만 내부에서 생물량이 많았다. 각 계절 정점간 군집구조를 rank correlation을 이용하여 주성분 분석한 결과, 정점간에는 큰 차이가 없었고 계절에 따른 군집구조 변화는 뚜렷하였으며, 그 변화는 수온, 혹은 수온과 상관관계를 갖는 요인에 의하여 좌우됨을 알 수 있었다. 조사해역은 수온의 연교차가 크고, 조류에 의한 해수의 혼합이 활발하여 이에 적응한 소수종이 우점하고 이 우점저어류는 퇴적물의 입도에 따라 그 분포가 결정되지만, 출현 개체수가 적은 대부분의 종은 정점간에 큰 차이를 보이지 않고 계절에 따라 군집구조가 변하여 가는 것으로 보인다.

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태풍 에위니아 (0603) 통과 후 상층해양 변동 특성과 영향 (A Study on Upper Ocean Response to Typhoon Ewiniar (0603) and Its Impact)

  • 정영윤;문일주;김성훈
    • 대기
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    • 제23권2호
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    • pp.205-220
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    • 2013
  • Upper ocean response to typhoon Ewiniar (0603) and its impact on the following typhoon Bilis (0604) are investigated using observational data and numerical experiments. Data used in this study are obtained from the Ieodo Ocean Research Station (IORS), ARGO, and satellite. Numerical simulations are conducted using 3-dimensional Princeton Ocean Model. Results show that when Ewiniar passes over the western North Pacific, unique oceanic responses are found at two places, One is in East China Sea near Taiwan and another is in the vicinity of IORS. The latter are characterized by a strong sea surface cooling (SSC), $6^{\circ}C$ and $11^{\circ}C$ in simulation and observation, under the condition of typhoon with a fast translation speed (8m $s^{-1}$) and lowering intensity (970 hPa). The record-breaking strong SSC is caused by the Yellow Sea Bottom Cold Water, which produces a strong vertical temperature gradient within a shallow depth of Yellow Sea. The former are also characterized by a strong SSC, $7.5^{\circ}C$ in simulation, with a additional cooling of $4.5^{\circ}C$ after a storm's passage mainly due to enhanced and maintained upwelling process by the resonance coupling of storm translation speed and the gravest mode internal wave phase speed. The numerical simulation reveals that the Ewiniar produced a unfavorable upper-ocean thermal condition, which eventually inhibited the intensification of the following typhoon Bilis. Statistics show that 9% of the typhoons in western North Pacific are influenced by cold wakes produced by a proceeding typhoon. These overall results demonstrate that upper ocean response to a typhoon even after the passage is also important factor to be considered for an accurate intensity prediction of a following typhoon with similar track.

Zoogeography of Taiwanese Fishes

  • Nakabo, Tetsuji
    • 한국어류학회지
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    • 제21권4호
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    • pp.311-321
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    • 2009
  • Three categories (freshwater, amphidromous, and marine fishes) of Taiwanese fishes are analyzed on the basis of zoogeographic elements, viz. China element, Indo-China element, Indo-West Pacific element, Indo-Pacific element, North-Pacific element, Japan-Oregon element, and circumtropical element. Freshwater fishes, which include the China and Indo-China elements, are distributed on part of the boundary area between the Palaearctic and Oriental regions of Wallace (1876). Diadromous fishes include the North-Pacific, Indo-China and Indo-West Pacific elements. Taiwanese salmon, a landlocked (initially diadromous) species that became established in Taiwan between 0.5 my B.P. and the early Pleistocene, is recognized as a distinct taxon included within the Oncorhynchus masou complex, which comprises here three species and two subspecies, viz. Oncorhynchus masou masou (Sancheoneo, Songeo, Sakura-masu or Yamame), O. masou ishikawae (Satsuki-masu or Amago), O. sp. (Biwa-masu), and O. formosanus (Taiwanese salmon), based on molecular, morphological and biological studies. Marine fishes are discussed under the following headings, brackish-water fishes (fishes of brackish waters and seas adjacent to continental coastlines, North Pacific and Indo-West Pacific elements; fishes of brackish waters and seas primarily around islands, Indo-West Pacific element), reef fishes (fishes of inshore reefs along continental coastlines from 0 to ca.100 m depth, Indo-West Pacific element; fishes of inshore reefs primarily around islands from 0 to ca.100 m depth, Indo-West Pacific element; fishes of offshore reefs along continental shelf edges from ca.150 to 300 m depth, circumtropical and Indo-Pacific elements; fishes of offshore reefs primarily around islands from ca.150 to 300 m depth, Indo-Pacific element), demersal fishes (fishes on continental shelves shallower than ca.150 m depth, Indo-West Pacific and Japan-Oregon elements; fishes on edges and upper continental slopes from ca.150 m to 500 m depth, Indo-West Pacific, Indo-Pacific, and circumtropical elements; fishes on lower continental slopes to abyssal plains from ca.500 m to 6,000 m depth, circumtropical element and rarely Indo-Pacific element), pelagic fishes (epipelagic fishes from 0 to ca.150 m depth, Indo-West Pacific, Indo-Pacific or circumtropical elements; meso- and bathypelagic fishes from ca.150 to 3,000 m depth, circumtropical element). The distribution of Taiwanese marine fishes are influenced by the Kuroshio Current, low-salinity and low-temperature waters from mainland China, and sea-bottom topography.

충청남도 녹도해역의 인공어초 효과와 상태에 관한 연구 (A Study on the Research Condition and Efficiency of Artificial reefs of Rokdo Sea region of Chungnam Province)

  • 박종수;서만석;김지현
    • 수산해양교육연구
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    • 제13권1호
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    • pp.87-98
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    • 2001
  • 1. The bottom mean size of the research area had been showed 86.8% in, 13.2% in mud artificial sector, but and 82.4% in mud at comparative sector. 2. The water temperature had been showed $11.2{\sim}12^{\circ}C$ in surface, $10.9^{\circ}C$ in mid layer, $10.6{\sim}10.8^{\circ}C$ in lower layer. also, The salinity had been showed $31.85{\sim}31.95_{psu}$ in surface, $31.82{\sim}31.97_{psu}$ in mid layer, $31.85{\sim}31.97_{psu}$ at lower layer. The transparency was showed 3.6~5.6m. 3. The conservation condition of reefs was partially grooved and buried the lower part of reefs established '95~'96years but was good condition generaly. 4. The attached fauna has been appeared fisheres botanical specise 6, fisheries animate species 5. 5. The lure of fisheres has been appeared 17 species in reefs sector, 10 species in comparative sector(natural fishing ground). 6. The catchs of C.P.U.E by fishery was catched 2.2~3.3 times in reefs sector than the natural fishing ground. but the individuals was much catched in traps. The jumbo type reefs gill netter were much catched in square artificial reefs. The weight of fishery was much captured in jumbo type reefs.

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군산 연안 어류의 군집 변동 (The Fluctuation of Fish Communities from the Coast of Kunsan, Korea)

  • 유봉석;최윤
    • 한국어류학회지
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    • 제5권2호
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    • pp.194-207
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    • 1993
  • 1992년부터 1993년까지 군산 연안 어류 군집의 계절적 변동을 조사하였으며, 조사 기간에 채집된 어종은 14목 47과 82속 98종이었다. 저인망에 의해서 채집된 어류 가운데 참서대 Cynoglossus joyneri와 꽃돛양태 Repomucenus ornatipinnis가 연중 가장 많이 출현하였고, 낭장망에 의해 채집된 어류로는 밴댕이 Harengula zunasi와 멸치 Engraulis japonica가 겨울을 제외한 계절에 우점어류로 나타났다. 낭장망에 의해 채집된 어류와 저인망에 의해 채집된 어류의 생체량은 계절에 따라 차이를 보였는데, 전자의 경우 여름철에 후자의 경우 늦봄과 겨울철에 가장 많은 양을 나타냈다. 이러한 결과는 여름철에 양태 Platycephalus indicus, 겨울철에 꼼치 Liparis tanakai가 조사 해역에서 많은 출현량을 나타내기 때문이다. 이들 어류는 특히 산란기에 내만쪽으로 모여든다. 한편 조간대에서는 모두 14종의 어류가 출현하였는데 이들 중 13종은 망둑어과 어류이며 산란기에 다량 출현함으로서 군산 연안은 많은 연안 어류의 산란장으로 여겨진다. 조사 기간 동안에 낭장망, 족대, 저인망, 그 밖의 어망으로 채집한 어류의 계절별 종 수는 봄철에 64종, 여름철에 59종, 가을철에 63종, 겨울철에 27종이었으며 군산 연안 어류의 계절별 출현량 및 종조성 변동은 주로 수온의 영향을 받는 것으로 사료된다.

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동중국해에서 해양환경 변화에 따른 노무라입깃해파리의 연간 출현 변동 파악 (Inter-annual occurrence variation of the large jellyfish Nemopilema nomurai due to the changing marine environment in the East China Sea)

  • 윤은아;차철표;황두진;윤양호;신형호;곽두성
    • 수산해양기술연구
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    • 제48권3호
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    • pp.242-255
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    • 2012
  • The Nemopilema nomurai a very large jellyfish that has been found in the East China Sea and is now are migrating to Korea and Japan. To investigate the occurrence of N. nomurai based on the changing marine environment of the East China Sea, we conducted field survey in the early summer from 2006-2008. We observed the marine environment using CTD and the occurrence of N. nomurai using FMT and bottom trawling. We caught the most N. nomurai in 2007 and the fewest in 2008 and environment factors influencing its are more sensitive temperature than salinity. Large quantities of N. nomurai with a small bell diameter were caught in 2007 and large individuals with a significant bell diameter were caught in 2008. This appeared which between the catch and bell diameter of N. nomurai had (-) correlation (R=-0.988, p=0.098). Meanwhile, the spatial distribution of N. nomurai concentrations in lower salinity mixed seawater inflow in Changjiang Diluted Water.

서태평양 적도 지역의 플라이스토세 후기 고해양 변화 (Late Pleistocene Paleoceanographic Changes of the West Equatorial Pacific)

  • 유찬민;형기성;문재운;김기현;지상범
    • Ocean and Polar Research
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    • 제26권2호
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    • pp.175-185
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    • 2004
  • To delineate Late Pleistocene paleoceanographic change of the West Pacific, we analyzed the oxygen and carbon isotopic ratios of two planktonic foraminifera species (G. sacculifer and N. dutertrei) from a piston core (KODOS-313) taken from the West equatorial Pacific, and they are compared with the published results of the East Pacific (ODP site 847 and RC 11-210), in terms of relative amounts and mass accumulation rates of $CaCO_3$ and eolian component, back to marine isotopic stage (MIS) 6. Differences in oxygen and carbon isotope values between two foraminifear species ($0.75%_{\circ}$ in ${\delta}^{18}O$, $0.05%_{\circ}$ in ${\delta}^{13}C$) are less than those of the East Pacific ($1.30%_{\circ}$ in ${\delta}^{18}O$, $0.14%_{\circ}$ in ${\delta}^{13}C$), which indicates smaller vertical contrasts in both temperature and nutrient between mixing-zone and thermocline in the West Pacific. Strong deviation in${\delta}^{18}O$ of G. sacculifer from SPECMAP suggests the carbonate fraction of KODOS-313 was subjected to partial dissolution by bottom water under lysocline. Lower accumulation rates of $CaCO_3$ and eolian component during glacial times are likely due to low sedimentation rate (ave. 0.75 cm/1000 yr) combined with carbonate dissolution in KODOS-313 site. However, the high $CaCO_3$ contents during the glacial periods clearly follow the general pattern of equatorial Pacific ocean.