• 한국수산과학회지
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• 제29권5호
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• pp.614-619
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• 1996

자연환경 아래에서 동죽의 산소소비 경향을 파악하기 위하여 1994년 1월부터 12월까지 매월 군산연안 간석지에서 채집한 동죽을 대상으로 산소소비량을 측정하였다. 동죽은 각장 2cm 그룹(1세군)과 각장 3cm 그룹 (2세군)으로 나누어 실험하였다. 온도와 염분에 따른 각장 그룹별 산소소비경향을 보면 각장 2cm 그룹과 3cm 그룹 모두 온도와 염분이 낮을수록 산소소비량은 감소하는데 온도에 따른 감소 경향보다는 염분 저하에 따른 감소 경향이 더 크게 나타났다. 그리고 각장 3cm 그룹에서의 감소율이 각장 2cm 그룹에서 보다 더 크게 나타났다. 한편, 계절에 따른 동죽의 산소소비경향은 간석지 온도에 따라 변화하는데 동절기인 2월에는 $0.5\;O_2mg{\cdot}g^{-1}{\cdot}h^{-1}$ 미만의 낮은 산소소비량을 보이지만 하절기인 $7\~8$월에는 $1.93\~2.44\;O_2mg{\cdot}g^{-1}{\cdot}h^{-1}$의 높은 산소소비량을 나타내었다. 각장에 따른 산소소비경향은 각장 2cm 그룹이 3cm 그룹에 비하여 높은 산소소비량을 나타내었으며, 두 그룹간의 산소소비량 차이는 온도가 높은 하절기에 더욱 크게 나타났다. 계절 온도에 따른 산소소비의 경향을 회귀직선식으로 표시하면 각장 2cm 그룹의 경우는 $Y=e^{-1.6312+0.0879X}(r^2=0.9466)$, 각장 3cm 그룹의 경우는 $Y=e^{-2.2366+0.0994x}(r^2=0.9305)$로 각각 표시되었으며, 두 그룹간 기울기에 유의의 차가 없어 계절에 따른 산소소비 경향은 두 그룹간에 차이가 없었다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권4호
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• pp.344-350
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• 1998

Seasonal variations in the feeding behaviour of Jamunapari and Barbari goat breeds and their utilization of browse and grass nutrients was evaluated in a promising 3-tier (Leucaena leucocephala- Dichro-stachys nutan-Cenchrus ciliaris) reconstituted pasture during summer, rainy and winter season of the years 1987 and 1988. Distinct diurnal pattern of feeding was observed with both the breeds. Jamunapari goats spent significantly more time foraging during winter season (352.0 min) followed by summer (306.0 min) and least in rainy season (277.0 min). Though no significant difference was observed in the relative time spent by Barbari goats on grazing activities during summer and winter season, they spent significantly more (p < 0.05) time during rainy season as compared to other two seasons. The preference of grazing goats for certain plant species in relation to others was evident with distinct seasonal and breed variations. DM intake (g/kg $BW^{075}$) varied significantly (p < 0.05) from season to season. Among the browse. L. leucocephala was prefered over D. nutan irrespective of breed over the seasons. There was no breed difference in DM intake, or proximate composition and nutrient digestibility of ingested herbage. The available nutrient content of ingested forage was found sufficient to meet the nutrient requirements of adult goats for maintenance (NRC, 1981). The reconstituted 3-tier pasture dominated by plant species like L. leucocephala and Cenchrus species appear to have great potential to sustain the nutrient requirement of goats without adverse seasonal fluctuations in pasture quality.

• 대한지역사회영양학회지
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• 제12권2호
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• pp.142-149
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• 2007

To evaluate the seasonal differences of nutrient intake and serum biochemical indices (total cholesterol, HDL-, LDL- cholesterol, TG, MDA : malondialdehyde, TAS : total antioxidant status, folate) in Korean college women with a mean age of 20.15y, this study was conducted twice: once in winter and a second time in summer. Anthropometric assessment was also measured in the two seasons. As a result body fat mass (p<0.05), body fat% (p<0.05), and abdominal fat% (p < 0.01) in the summer were significantly lower than those in winter. Intake of fat (p < 0.05), polyunsaturated fatty acid (p < 0.01), zinc (p < 0.05), and vitamin E (p < 0.05) were at significantly higher levels in the summer period compared with the winter period. In addition, nutrients with an intake level less than 75% RI of KDRIs were folate in winter and calcium, and folate in the summer. Total cholesterol (p < 0.05) and HDL-cholesterol in summer, according to lipid profiles, were significantly lower than those in winter. Although MDA, one of the products of lipid peroxidation, remained unchanged, TAS was significantly higher in summer than in winter. The level of folate in summer showed significantly lower than that in winter. The present study suggests that nutrient intake of college women women differs according to the seasons and anthropometric indices and serum biochemical indexes were associated with seasons. Thus nutritional education programs on the basis of season are needed for college women.

• 한국패류학회지
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• 제18권1호
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• pp.1-8
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• 2002

경남 고성만과 강진만에서 서식하는 굴과 피조개에 대한 체성분의 계절적 변화를 Station별로 조사 분석하였다. 굴의 경우 대체로 조사정점에서 모두 여름에 단백질의 함량이 높았으며, 겨울 동안 지질과 탄수화물의 함량이 높아 정점 간에는 뚜렷한 차이는 없었으나, Station 2에서 다소 양호한 상태를 나타내었다. 글리코겐의 함량은 여름에 현저히 감소하였으며, 에너지 함량은 11월부터 이듬해 3월까지 높은 값을 나타내었다. 한편 피조개의 경우 단백질은 여름 동안 낮았으나 탄수화물은 높게 나타났다. 지질은 2-5월 동안 높았으며, 글리코겐의 함량은 6-9월 동안 낮았고, 에너지 함량은 겨울 동안 낮게 나타나 어장간의 뚜렷한 차이는 없었다.

• 수산해양기술연구
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• 제46권4호
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• pp.376-391
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• 2010

To investigate seasonal variation and species composition by depth layers in the deep sea ecosystem of the East Sea of Korea, bottom trawl survey was conducted at 4 depth layers during spring and autumn from 2007 to 2009. A total of 47 species were collected and were composed of 23 fish species, 9 crustacea, 6 cephalopoda and 9 gastropoda. The main dominant species at each depth layers were Chionoecetes opilio in 300m, Berryteuthis magister in 500m, Chionoecetes japonicus in 700m and 900m. In spring, richness indices (R) showed low value of 2.01 in 500m depth, and high value of 2.16 in 300m depth. Diversity indices (H') showed low value of 1.53 in 300m depth, and high value of 2.09 in 700m depth. Dominance indices (D) showed low value of 0.15 in 700m depth, and high value of 0.31 in 300m depth. In Autumn, richness indices showed low value of 1.48 in 900m depth, and high value of 2.69 in 300m depth. Diversity' indices (H') showed low value of 1.13 in 300m depth, and high value of 2.23 in 700m depth. Dominance indices (D) showed low value of 0.14 in 700m depth, and high value of 0.54 in 300m depth. In spring, similarity analysis in each depth layers showed the difference between 900m and othe depth layer, on the contrary 500m and 700m showed the similarity. In autumn, similarity analyssis in each depth layers showed the difference between 700m and other depth layers, on the contrary 300m and 500m showed the similarity.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권1호
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• pp.68-74
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• 2003

본 연구에서는 해안 대수층에서 SHARP수치모델을 이용하여 해수와 담수의 경계면 및 해수침투 범위를 추정하고, 계절적인 영향에 대한 모델의 민감도를 분석하였다. SHARP수치모사에 의한 해수와 담수의 경계면이 연구지역내 관측정에서 측정된 해수와 담수의 경계면보다 계절적인 변화에 대하여 더 민감하게 반응하였다. 분산형 모델인 SUTRA를 이용하여 TDS와 벡터 분포를 계산하고, SHARP모델에 의하여 만들어진 Ghyben-Herzberg 경계면과 비교한 결과, 해수침투 범위의 차이는 50m이하이며, 계절적인 영향에 의한 해수침투 변동폭의 차이는 약 12m로 나타났다. 이러한 해수침투 범위의 차이는 해안 대수층의 수치모사에 이용된 광역적인 규모에 비하면 작은 편이다. 본 연구지역과 같이 광역적인 규모의 해안 대수층에서 해수와 담수의 경계면을 추정하는데, SHARP모델은 매우 유용한 것으로 사료된다. 그러나 경계면 모델은 확산이 우세한 국지적인 규모의 모델링에서는 정확한 해수침투의 범위를 모사하는데 약간의 한계가 있는 것으로 보인다.

• Asian Journal of Atmospheric Environment
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• 제7권2호
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• pp.85-94
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• 2013

Methane concentrations have been monitored at the Anmyeon-do Observatory, Korea, since 1999. In recent years, the methane concentration has increased, but the sources of this increase have yet to be identified. This study was designed to identify the major source contributing to the increase by using World Data Centre for Greenhouse Gases (WDCGG) data and the Greenhouse Gases Emission Presumption (GEP) method. The data were collected at Anmyeon-do between 2003 and 2009 (except 2008), and the analyses showed that the increase in methane concentration originated mainly in rice paddies around the observation point. The annual average methane concentration at Anmyeon-do was 1894 ppb, of which 100-103 ppb (5.3-5.4%) was shown to originate mainly from rice paddies. The seasonal fluctuation in methane concentration from May to October estimated by the GEP method was compared with experimental data of previous research conducted on rice paddies. The close match obtained through this comparison shows that the GEP method is effective. The difference in methane concentration was also analyzed in terms of land use and land cover. It was shown that although rice paddies account for only 14.7% of the area surveyed, they accounted for between 69 and 90% of the total increase in methane concentration. These results confirm that rice paddies are the main source of the increase in methane concentration observed at Anmyeon-do.

• The Korean Journal of Ecology
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• 제20권6호
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• pp.451-459
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• 1997

Seasonal and spatial distribution of vascular plants were examined and related to soil texture, pH, moisture and nutrient contents in the riparian zone of the Balan Stream. In spring the area was dominated by Alopecurus aequalis var. amurensis, was displaced by Persicaria thunbergii and Humulus japonicus in summer. From the stream channel to bank, soil texture and pH were not significantly differentiated, moisture decreased, organic matter and K increased, and TKN and available P increased in June and decreased in August. DCA ordination analysis by species distribution showed spatially and seasonally distinct patterns seasonal difference was evident on axis 1, and spatial difference according to the distance from stream channel was clear, too. Both axis 1 and axis 2 scores were significantly correlated with biomass, pH, and phosphate. Species richness increased were significantly correlated with biomass, pH, and phosphate. Species richness increaed with increasing organic matter and phosphate, and decreased with increasing soil moisture and K. Biomass increased with increasing organic matter, but was negatively related to pH, moisture, TKN, available P and K. Available P was significantly correlated with biomass, pH, and total soil nitrogen. In conclusion, the distribution of riparian vegetation was governed by soil physico-chemical properties, which are primarily determined by how far it is from the stream channel.

• 수산해양기술연구
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• 제54권3호
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• pp.204-216
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• 2018

A study for species composition and abundance of the fish assemblages in the coastal Sacheon Bay, Korea were conducted using monthly collection by a shrimp beam trawl from March 2015 to February 2016. The number of individuals, biomass and species diversity indices fluctuated with the station and month. Of all 73 species collected, the dominant species in terms of numbers were Liparis tanakae, Zoarces gillii, Amblychaeturichthys hexanema, Ricuzenius pinetorum and Pleuronichys cornutus. The peak number of fishes occurred in March and April, whereas the biomass of fishes was highest in April. The numbers and biomass of fishes were lower in February corresponding with the low temperature, and diversity indices were highest in June. Due to those seasonal difference in abundance of the dominant species, fish community were divided into three main groups. In addition, seasonal difference by station of fish community were devided into four main groups. Juvenile fishes of coastal Sacheon were presented during the study period. It presented that the study area served as an important role in spawning and nursery ground for fisheries resource.

• 한국농공학회지
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• 제44권5호
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• pp.127-135
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• 2002

Water quality samples were taken for every two hours whenever runoff occurred by rainfall to investigate concentration variations of T-N, T-P and SS during runoff process from a paddy field. The difference between the highest concentration in a runoff event and flow weighted mean concentration for T-N, T-P, SS placed between 3.07∼40.16%, 11.44∼60.80%, and 15.11∼64.5%, respectively. The difference between the lowest concentration in event and event mean concentration for T-N, T-P, SS ranged between -7.24∼-31.84%, -11.59∼-47.86%, and -5.21∼-36.20%, respectively. The relationship between runoff and mass load was derived for each storm event using observed data. The relationship between runoff and mass load showed linear relationship regardless of water quality constituents and rainfall amount. The results suggested that relationship between T-N and T-P loads and runoff should be prepared separately in considering of fertilization effect and seasonal conditions. The relationship between SS and runoff should be made to reflect seasonal conditions and tillage effect.