• 제목/요약/키워드: Seasonal Variations

검색결과 1,049건 처리시간 0.031초

용문천 저서성 대형무척추동물 군집의 변화 (Change of Benthic Macroinvertebrates Community in the Yongmoonchun, Yang Pyong)

  • 진재호;임영득
    • The Korean Journal of Ecology
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    • 제20권6호
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    • pp.461-470
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    • 1997
  • There are 7 classes, 17 orders, and 141 species of benthic macroinvertebrates at the 5 study sites from Feb, '91 to May, '92. Total species frequency number has less variations among sites than seasonal changes. Not considering seasonal changes this indicates that there are some influences from outside pollution sources. Seasonally, Ortho chadiinae sp. 2 take 21.2% share of total species. It was the dominant species in Feb. '91. With total average level Ephemeroptera take 51.3% of total species as first dominant species. Diptera 27.8% as second dominant species and Trichoptera 16.7% as third dominant species. Through these biological indexes, they appear to have unstable living environments in summer at sites 1 and 5. One can see that site 1 is more polluted than site 3 because site 1 has more pollution sources such as pastures and recreation areas.

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Effects of seasonal variations in temperature and transport stressor on blood protein and glucose concentrations in wild teleosts of marbled sole(Limanda yokohamae) and greenling(Hexagrammos otakii)

  • Kim, Ki-Hong;Ahn, Kyong-Jin;Kwon, Se-Ryun;Huh, Sung-Hoi
    • 한국어병학회지
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    • 제14권1호
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    • pp.54-58
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    • 2001
  • The seasonal trends of plasma protein and glucose concentrations in marbled soles(Limanda yokohamae) and greenlings(Hexagrammos otakii), and the influence of transport stressor on those levels were investigated. Total plasma protein levels of marbled soles and greenlings in late spring and summer were significantly higher than those in winter(January). Plasma glucose levels were consistently increased according to elevation of water temperature both in marbled soles and greenlings. Transport stressor gave rise to decrease of plasma protein levels and increase of blood glucose levels.

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Studies on the Seasonal Variations of Plankton Organisms and Suspended Particulate Matter in the Coastal Area of Ko-Ri

  • Choe, Sang
    • 한국해양학회지
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    • 제7권2호
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    • pp.47-58
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    • 1972
  • Densities and composition of phytoplankton and zooplankton, concentrations of particulate organic carbon, particulate organic nitrogen, and particulate inorganic matter were determined in the coastal area of Ko-ri during one year. There are peaks of densities of plankton organisms in summer, autumn, and spring Concentrations of particulate organic carbon ranged from 35 to 3,785 mg/㎥ (averaging 868mg/㎥ ), particulate organic nitrogen ranged from 4.4 to 158mg/㎥ (averaging 45mg/㎥), inorganic suspended matter ranged from 0.6 to 11.6 mg/L (averaging 5.7mg/L), and the carbon-nitrogen ratios of the suspended matter were varied from 0.5 to 231(averaging 35), with each seasonal cycle. The phytoplankton density and particulate organic carbon were possitively correlated from March to November, negatively from December to February, and the zooplankton dinsity and particulate organic nitrogen were well correlated.

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Persulfate Wet Oxidation Method for the Determination of Total Phosphorus in Atmospheric Aerosols and Its Application for a Year-round Observation in Beijing

  • Okuda, Tomoaki;Gunji, Yuma;He, Kebin;Ma, Yongliang
    • Asian Journal of Atmospheric Environment
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    • 제7권3호
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    • pp.169-175
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    • 2013
  • Measurement of the phosphorus concentration in aerosols in Beijing, which was a representative East Asian mega-city, was carried out. The optimum procedure for analyzing phosphorus in aerosols was found in this study. Recovery of phosphorus in environmental samples through the improved method was almost 100%. The concentration of phosphorus in TSP was $145{\pm}47\;ng/m^3$, with a seasonal variation showing high concentrations in winter and low concentrations in summer. The concentrations of phosphorus in $PM_{2.5}$ accounted for $35{\pm}6%$ of those in TSP, with no seasonal variations. The major source of phosphorus in aerosols in Beijing was soil dust, and additional sources of phosphorus in fine particles could be coal combustion and biomass burning.

Bacteriological Water Quality of Lake Eui-Am

  • Choe, Sang;Kim, Geon Chee
    • 한국해양학회지
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    • 제6권2호
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    • pp.78-84
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    • 1971
  • A year-long survey of bacteriological water quality for Lake Eui-am in Kang- won Province, Korea, was conducted from June 1970 to May 1971. the purpose of this investigation was: 1) to determinate the seasonal prevalence of fecal pllution bacteria, such as coliforms, fecal coliforms and enterococci, in Lake Eui-am; 2) to correlate these findings with associated microbiological parameters; and 3) to interpret these results with respect to water quality and environmental health. The membrane filter techniques were used, for the determination of these bacteria.Densities of total coliforms, fecal coliforms and enterococci exhibited seasonal variations, the numers of these fecal pollution bacteria being high in summer and fall months in close possitive relation to the amount of rainfall, and being low winter and spring months. On the whole, the level of fecal pollution bacteria in Lake Eui-am is yet quite low There were not any evident correlation among the density of these pollution bacteria. The ratio of fecal coliforms to enterococci of the lake water varied from 0.01 to 4.25 with average of 1.47.

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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.

The Effect of Fluctuations in Photoperiod and Ambient Temperature on the Timing of Flowering: Time to Move on Natural Environmental Conditions

  • Song, Young Hun
    • Molecules and Cells
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    • 제39권10호
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    • pp.715-721
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    • 2016
  • Plants have become physiologically adapted to a seasonally shifting environment by evolving many sensory mechanisms. Seasonal flowering is a good example of adaptation to local environmental demands and is crucial for maximizing reproductive fitness. Photoperiod and temperature are major environmental stimuli that control flowering through expression of a floral inducer, FLOWERING LOCUS T (FT) protein. Recent discoveries made using the model plant Arabidopsis thaliana have shown that the functions of photoreceptors are essential for the timing of FT gene induction, via modulation of the transcriptional activator CONSTANS (CO) at transcriptional and post-translational levels in response to seasonal variations. The activation of FT transcription by the fine-tuned CO protein enables plants to switch from vegetative growth to flowering under inductive environmental conditions. The present review briefly summarizes our current understanding of the molecular mechanisms by which the information of environmental stimuli is sensed and transduced to trigger FT induction in leaves.

수수꽃다리 잎중의 다가 알코올과 유리 환원당의 소장에 관한 연구 (Studies on the Seasonal Variation of the Polyalcohols and the Free Reducing Sugars in the Leaves of Syringa dilatata $N_{AKAI}$)

  • 김창민;류경수
    • 생약학회지
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    • 제1권2호
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    • pp.23-28
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    • 1970
  • One of the indigeneous plants to this country, Syringa dilatata $N_{AKAI}$ (Oleaceae) is known in commerce as 'Ya-Jung-Hyang' (野丁香) and has been known to be of effect as bitter stomachics. Seasonal variations in the content of polyalcohols and free reducing sugars in leaves of this plant which contains syringin glycoside, mannitol and free reducing sugars etc. were studied. Application of chromotropic acid to formaldehyde which was obtained from polyalcohols and reducing sugars by treatment with periodic acid results in reddish violet coloration and the solution has absorption maximum at wave length $570m\;{\mu}$. By the use of ionic exchange resin chromatography, poyalcohols were separated from the above mixture. The content of polyalcohols of this plant was plentiful in the growing season while that of free reducing sugars was decreasing vice versa.

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매스콘크리트의 계절에 따른 온도이력과 압축강도에 관한 실험 (Study on Temperature History and Compressive Strength of Mock-up Concrete Considering Seasonal Change)

  • 김영주;공민호;김광기;양동일;박무영;정상진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2005년도 추계 학술논문 발표대회
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    • pp.89-92
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    • 2005
  • Our country has experienced variations in temperature as belong to the area of the continental climate that shows four significant seasons. These occur quality of construction. As the hydration of cement processes, the strength of concrete is developed. In order to improve the quality of concrete, various conditions including temperature and humidity should be maintained appropriately and concrete itself should be cured sufficiently This paper is basic experiment for estimating influence of strength by seasonal mock-up concrete's heat of hydration and estimate relationship of compressive strength development by curing temperature. And show basic document as quality control.

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담수산 석패와 7종의 발생시기에 관한 연구 (Seasonal Gonadal Cycle of the Seven Species of Freshwater Unionidae ( Pelecypoda : Unionoida ))

  • 박갑만;권오길
    • 한국패류학회지
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    • 제11권2호
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    • pp.147-163
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    • 1995
  • The unionid family Unionidae contains several genera in Korea, among which occru considerable variations in life histories and sexual conditions. Seven species from the Korea(Anodonta arcaeformis flavotincta, A. woodiana, Unio douglaseae, U. douglasiae sinuolatus, Lamprotula gottschei, Lanceolaria acrorhyncha, Solenaia triangularis)were stueide in order to identify and describe the seasonal gonadal activity and the visceral sex. The gonads of seven species were histologically examined by using the paraffin block technique for sectioning. All seven species were uniformly dioecious and testicular activity in six species except one species, S. triangularis, generated sperm-morulae(multinucleated cell). The annual reproductive cycle of the seven species could be classified into five successive stages; multicative, growing, mature, spent, deginerative and resting stages. The breeding season of six species was the summer and that of A. a. flavotincta was the winter.

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