• 한국수산과학회지
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• 제50권4호
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• pp.429-436
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• 2017

The seasonal and interannual variations in fish assemblages in the coastal waters off Gijang were examined with an otter trawl from 2015 to 2016. A total of 59 fish species was collected during the study period. The dominant species were Caelorinchus multispinulosus, Clupea pallasii pallasii and Chelidonichthys spinosus. Seasonal changes in fish assemblages appeared to be distinct in the study area. The fish assemblages in summer and autumn were clearly distinguishable from those in other seasons, and the largest numbers of species and individuals were captured in winter and summer, respectively. Because fish assemblages are closely related to changes in water temperature, long-term changes in water temperature can have a significant impact on the productivity of offshore fisheries by changing fish species composition, habitat migration, and growth rate of fish.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.24-24
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• 2004

This study was investigated to the seasonal variation of attached diatoms communities in the Hantan River in November 2001, February, Ma and August 2002. It was identified the total 107 taxa which were composed of 95 species, 11 varieties and 1 unidentified speCies. The standing crops ranged 298,5004,776,000cells${\cdot}cm^{-2}.$and showed marked irregularly seasonal variations. It was higher value at the lower station than the upper station in fall. But it was similar values from the upper to the lower station by the effect of typhoon in summer. Chlorophyll concentrations ranged $13.4~304.2{\mu}m{\cdot}cm^{-2}.$ Standing crops and chlorophyll showed similar trends during investigation. Low diversity index values probably indicated the effects of envi~onmental stresses(water temperature, flow and current velocity) other than organic pollution. An assessment of organic pollution using epilithic diatoms(DAlpo) was $\alpha$-oligosaprobic states at the upper and mid stations, and was $\alpha$-mesosaprobic states at the lower stations.

• 한국환경과학회지
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• 제19권1호
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• pp.81-87
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• 2010

Cool island intensity urban green space was investigated based in Dalsung Park, that is one of the largest parks in Daegu. Cool island intensity(CII), which is defined as the temperature difference between the green space and its surrounding built-up areas, shows time variations. A through-year measurement(2008-2009) of ground level air temperature revealed seasonal variation and relationship to the atmospheric condition of CII. The temperature variation in the park and the reference downtown Daegu was as same order as CII. The noontime CII is larger in summer than that in winter due to the leaf fall of the park trees. On the other hand, seasonal variation of nighttime CII is not so clear. The nighttime CII was larger under the stable atmosphere.

• 한국환경보건학회지
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• 제22권4호
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• pp.55-61
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• 1996

Measurements of the seasonal variations of concentration and size distribution of TSP, $SO_4^{2-}, NO_3^-, Cl^-, NH_4^+, Na^+, K^+, Ca^{2+}$ and $Mg^{2+}$ were made by Andersen air sampler from May 1995 to April 1996 in Seoul. The size distribution of these ions was divided into four patterns. 1) Distribution was concentrated on fine particles over a year such as $NO_3^-$ component, 2) Distribution was predominated in coarse particles fraction over a year such as $Mg^{2+}$ and $Ca^{2+}$ components, 3) Distribution was differerent from various seasons such as $NH_4^+, SO_4^{2-}, Cl^-$ and $K^+$ components, 4) Distribution was bi-modal such as $Na^+$.

• Ocean and Polar Research
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• 제36권4호
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• pp.437-445
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• 2014

A time-series sediment trap was operated at a water depth of 4950 m from July 2003 to May 2004 at KOMO station ($10^{\circ}30^{\prime}N$, $131^{\circ}20^{\prime}W$) in the northeastern equatorial Pacific, with the aim of understanding the temporal variation of planktonic foraminifera assemblages in response to the seasonal shift of Inter-Tropical Convergence Zone (ITCZ). A total of 22130 planktonic foraminifera specimens belonging to 30 species and 11 genera were identified, which shows a distinct seasonal variation with high values (125~288 specimens $m^{-2}day^{-1}$) in the winter to spring (December-May) and low values (16~23 specimens $m^{-2}day^{-1}$) in the fall (September-November). In addition, seasonal ecological differences of foraminifera assemblages are distinctly recognizable: omnivorous foraminifera occurred predominantly during the summer season, whereas herbivorous ones were dominant during the winter season. Such seasonal variations correspond to the seasonal shift of the ITCZ. Enhanced occurrence of herbivorous species during the winter-spring season seems a result of surface water mixing generated by the southward shift of the ITCZ. The increase in omnivorous species during the summer season may be due to the northward movement of the ITCZ caused by weakened wind speed, resulting in the intensification of water column stratification and nutrient-poor environment. A significant reduction of planktonic foraminifera specimens during the fall is attributed to heavy precipitation and reduction in light intensity.

• 생물정신의학
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• 제17권3호
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• pp.153-160
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• 2010

Objectives : Recurrence of mood episodes associated with a specific season has been described in various mood disorders. Seasonal change in mood and behavior as a lifetime trait is also observed in healthy individuals. This study aimed at comparing the lifetime trait of seasonal variations of mood and behavior between bipolar disorder patients and controls as well as investigating associated factors of seasonality. Methods : Subjects were ninety-four clinically stable patients with bipolar disorder and 188 age- and sex-matched healthy controls. Seasonality of mood and behavior was assessed retrospectively on lifetime basis using Seasonal Pattern Assessment Questionnaire(SPAQ). Results : The patient group showed a higher median global seasonality score(GSS) of SPAQ and a higher rate of seasonal affective disorder(SAD) compared to the control group(p < 0.0001). For subjects showing prominent seasonality, the seasonal symptom profile and seasonal pattern was similar in both patient and control groups. In addition to the diagnosis, female gender was shown to be a predictor of seasonality in the multiple linear regression analysis(p = 0.045). Conclusion : This study suggests that lifetime trait of seasonality may be related to the susceptibility of bipolar disorder.

• Fisheries and Aquatic Sciences
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• 제12권2호
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• pp.130-137
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• 2009

Temporal variations of seaweed biomass and coverage were seasonally examined at Ongdo in the Yellow Sea, Korea from August 2006 to April 2008. Average seaweed biomass was 245.79 g/$m^2$ in wet weight and coverage was 16.49% with seasonal variations from 13.97% in spring to 18.55% in autumn. Seaweeds were distributed across the shore gradient from the high intertidal to 10m depth in the subtidal zone. Biomass was always higher in the subtidal zone (310.24 g/$m^2$) than in the intertidal zone (181.35 g/$m^2$). Of total seaweed biomass, 76.52% (first year) and 80.32% (second year) occurred from the low intertidal zone, down to depth of 1 to 5m. Gelidium amansii had the highest importance value and biomass, and sub dominant species were Chondrus ocellatus and Chondria crassicaulis. Coarsely-branched seaweeds comprised the highest proportion of biomass (214.84 g/$m^2$, or 87.41% of the total biomss). Seasonal variations in algal biomass were largely explained by fluctuations in the biomass of coarsely-branched and thick-leathery forms. In conclusion, seaweed biomass of Ongdo shore was very low because of perennial G. amansii showing low biomass as compared to kelp or Sargassum spp. However, these results indicate Ongdo is good place to grow seaweeds because coarsely-branched form seaweeds including G. amansii are dominant at unpolluted and clean environment.

• Journal of Astronomy and Space Sciences
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• 제36권2호
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• pp.61-68
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• 2019

We have investigated the variations of sporadic E (Es) layer using the measurements of digisondes at Icheon ($37.14^{\circ}N$, $127.54^{\circ}E$, IC) and Jeju ($33.4^{\circ}N$, $126.30^{\circ}E$, JJ) in 2011-2018. The Es occurrence rate and its critical frequency (foEs) have peak values in summer at both IC and JJ in consistent with their known seasonal variations at mid-latitudes. The virtual height of the Es layer (h'Es) during equinox months is greater than that in other months. It may be related to the similar variation of meteor peak heights. The h'Es shows the semidiurnal variations with two peaks at early in the morning and late in the afternoon during equinoxes and summer. However, the semi-diurnal variation is not obvious in winter. The semi-diurnal variation is generally thought to be caused by the semi-diurnal tidal variation in the neutral wind shear, whose measurements, however, are rare and not available in the region of interest. To investigate the formation mechanism of Es, we have derived the vertical ion drift velocity using the Horizontal Wind Model (HWM) 14, International Geomagnetic Reference Field, and Naval Research Laboratory Mass Spectrometer and Incoherent Scatter Radar-00 models. Our results show that h'Es preferentially occur at the altitudes where the direction of the vertical ion velocity changes. This result indicates the significant role of ion convergence in the creation of Es.

• 수면정신생리
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• 제20권2호
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• pp.63-68
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• 2013

목 적 : 일주기 유전자 다형성이 계절성 기분 장애의 발병 기전과 연관이 있다는 여러 연구 결과들이 보고되었다. 본 연구에서는 한국에 거주하는 건강한 성인을 대상으로 RORA (Retinoid-related orphan receptor A)유전자의 다형성과 계절성 변동의 관계를 살펴보고자 하였다. 방 법 : 신문 광고를 통해 모집한 507명의 지역사회 인구를 대상으로 하였다. 기분과 행동의 계절적 변동은 Seasonality Pattern Assessment Questionnaire(SPAQ)를 이용하여 평가하였다. RORA rs11071547 SNP는 PCR을 이용하여 유전자형 분석을 하였다. 여름형은 교란 요소로 작용할 것으로 판단되어, 29명의 여름형은 제외한 총 478명의 대상자를 분석하였다. 계절성군과 비계절성군의 유전자형 분포의 비교는 Chi-square test를 이용하였고, 전반적 계절성 점수(Global seasonality score, GSS)와 RORA rs11071547의 연관성은 ANCOVA로 분석하였다. 결 과 : 연구 참여자 507명 중 12.1%(겨울형 9.3%, 여름형 2.8%)가 SAD에 해당하였다. 계절성군과 비계절성군간의 RORA rs11071547의 유전자형 분포는 통계적으로 유의한 차이는 없었다. 전반적 계절성 점수(GSS)와 세부 항목인 수면시간, 사회활동, 기분, 에너지 수준에서 유의한 차이는 관찰되지 않았다. 그러나 세부 항목 중 체중과 식욕에서는 C 대립유전자 동형접함체군에서 유의하게 점수가 높은 양상을 관찰할 수 있었다(p=0.026, p=0.034). 결 론 : 본 연구에 참여한 대상자들에서 RORA 유전자 다형성이 체중과 식욕의 계절성 변화에 주요한 역할을 하며, 계절성 기분 장애의 감수성과도 어느 정도 연관이 있을 것으로 생각된다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2007년도 추계학술대회 논문집
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• pp.283-284
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• 2007