• 한국환경과학회지
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• 제3권4호
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• pp.333-348
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• 1994

The groundwater levels at 11 sites and the vertical variations o( the water Quality at 1 site were measured to study the characteristic of the groundwater level fluctuation of Cheju Island. The results of the measurements for the groundwater levels were as follows; In the eastern part, inculding Kimnyong, Jongdal and Sungsan, a sinusoidal fluctuation of groundwater levels occurred in response to oceanic tides. The tidal effect on the groundwater level was reduced depending upon the distance from seashore. But time lag showed that the trend is reversed. However, in the Samyang, Kosan and Shinhyo areas show that the groundwater level was directly influenced by the amount of precipitation. Especially, Shinhyo area which southern part in Cheju was affected the most and show upper parabasal groundwater level. In Susan- I which eastern part in Cheju, well rovealed that water Quality changed with the period of a tide. Salinity at the lim, bellow the natural groundwater level, was approched to the brackish groundwater(1000ppm).

• 암석학회지
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• 제5권1호
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• pp.89-107
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• 1996

제주도의 알칼리암류 및 솔라아이트에 대한 Sr, Nd 그리고 Pb 동위원소비의 특징은 서루 유사하거나, 솔리아이트가 조금 더 부화된 특징을 갖는다. 그러나 분출시기에 따라 솔리아이트의 즉징을 구분하면, 전기의 것은 Lee (1982)의 용암대지 형성기의 알칼리암류와 유사한 반면, 후기의 것은 이 연구의 알칼리암류와 유사하다. 이는 알칼리암류와 솔리아이트가 동질의 근원에서 유래하였음을 지시하며, 분출 시기에 따라 부분용융된 맨틀 근원지으 성질이 차이가 있었음을 시사한다. 제주도 화산암류는 사모아 군도의 화산암류의 변화 및 남중국 분지 화산암류의 변화 경향과 중첩되어 DMM과 EM II 사이의 혼합으로 잘 설명될 수 있는 변화경향을 지닌다. 이는 제주도를 제외한 우리나라의 신생대 화산암류 및 북동 중국 화산암류들이 DMM-EM I사이의 혼합으로 설명이 되는 변화경향을 보이는 것과 차이가 난다. DMM-EM II 맨틀 물질간의 섞임 계산 결과, 제주도 화산암류를 형성한 맨틀 물질은 결핍 맨틀 (DMM)에 부화된 맨틀 (EMII)물질이 약 10% 이내의 비율로 섞인 특징을 가짐을 지시한다. 제주도를 포함한 우리나라 및 중국의 신생대 화산암류의 동위원소적 특징을 북중국 지괴와 남중국 지괴으 충돌이론(예,Yin and Nie, 1993)과 결부시키면, 부화된 맨틀 물질의 공급원으로 고려되는 대륙암권 맨틀의 지화학적 조성이 지괴에 따라 차이가 있었음을 나타낸다. 즉 북중국 지괴는 EM I의 표식을, 남중국 지괴는 EM II의 표식을 가지고 있었을 경우로 설명될 수 있음을 제시한다.

• 한국패류학회지
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• 제26권3호
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• pp.227-234
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• 2010

A comparative analysis of size and age structures of coastal subfossil shell assemblages of the shortnecked clam Ruditapes philippinarum from open and protected bays of Cheju Island (Korea) was carried out. On the whole, taking into account the damage of small fragile shells, size and age structures of the shell assemblages corresponded to the classical curve of bivalve population distribution when its mortality diminishes with age increase up to a certain threshold. It was found that shell samples from open bays of the western, southern and eastern coasts included shells of smaller and younger individuals (L ${\leq}$ 40 mm, ${\leq}$ 4 years) than samples from the eastern protected bay (L ${\leq}$ 54.5 mm, ${\leq}$ 6 years). Evidently, strong wave activity was the reason for a short life-span of the clams from the open areas. Growth was investigated retrospectively by annual growth rings on the shells. Growth rates of the clams from the various coasts of Cheju Island differed. However, growth rates of the clams from different biotopes at the same (eastern) side of the Island were similar. Shell height/length and width/length ratios statistically significantly increased with the clam age increase. Most likely, the reason for such shell shape alteration is that more conglobated individuals more survive being more energy-optimal than oblong specimens.

• ALGAE
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• 제17권2호
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• pp.75-81
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• 2002

In this study the length of ITS2 from four species of the Ulvaceae in Jeju Island varied between 167 and 203 bp. The resuits of this investigation showed that two genus, Ulva and Enteromorpha are grouped in a monophyletic assemblage with 100% bootstrap support in all phylogenetic trees. However, a thorough eamination of these characters from representatives does not provided a way to identify any unique morphological features of clasdes in this tree. This study reveals that Ulva conglobata and Ulva pertusa belong to one clade in the phylogenetic tree with the samples from Jeju Island, Korea.

• 환경생물
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• 제26권3호
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• pp.226-232
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• 2008

Sampling of the ground beetles in four 'gotjawal' terrains of Jeju island was conducted from April to October, 2007, using pit-fall trap. Totally 2,887 individuals of 23 species belonged to 4 families were collected. The species diversity index was the highest at Aeweol gotjawal (AW), while it was the lowest in Hangyeong-Andeog gotjawal (HA). Clustering analysis revealed that the insect communities of four gotzawals were grouped in only one cluster. Jocheon-Hamdeog gotjawal (JH) formed a cluster with Gujwa-Sungsan gotjawal (GS) at the lowest chord distance (0.24). At the higher chord distance of 0.50, AW fused the cluster of JH and GS. HA fused with the rest three terrains, forming a single cluster at the highest chord distance of 0.98.

• 한국패류학회지
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• 제5권1호
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• pp.10-28
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• 1989

A study on the distribution and community structure of benthic macroinvertebrates on the intertidal zone of Cheju Island was carried out from June 1988 to May 1989. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 71 families and 135 species in this study. The dominant species of the upper tidal zone were Nodilittorina granularis and Heminerita japonica, those of the middle tidal zone were Monodonta neritoides and Lunella coronata coreensis, However, Monodonta neritoides and Chlorostoma arhyrostoma lischkei were dominant in the lower tidal zone. Community dominant indices were significantly high in the upper tidal zone. Macuoinvertebrates species which have the ability of resistance to the physical factors such as, strong waves and exposure to the hot sunlight were mainly distributed on the intertidal zone of Cheju Island. The difference in the number of species among seasons was not significant, but thao among zones was quite apparent and the lower the zone, the more abundant.

• 한국패류학회지
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• 제6권1호
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• pp.33-44
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• 1990

A study on the distribution and community structure of benthic molluscan shells of the northern coastal area in Cheju Island was carried out from July 1989 to June 1990. The benthic molluscan shells collected and identified were composed of 3 classes, 9 orders, 29 familes and 81 species. The first dominant species of the wpper intertidal zone of the northern coastal area in Cheju Island was Nodilittorina exigua and second dominant species were Heminerita japonica, Monodenta neritoides, Monodota neritoides, Littorina brevicula, those of middle intertidal zone were Lunella coronata coreensis, Monodonta neritoides and Omphalius rusticus. H. japonica, M. neritoides, O. rusticus, L. coronata coreensis and Niotha livescens were dominant in the lower intertidal zone, and Astralium haematragum was dominant in the infralittoral zone of within 60 feet sea water depth. The benthic molluscan standing biomass of intertidal and infralittoral zones were 145.71-705.55 gr/ /m sup 2 / and 84.57-1645.67 gr/m sup 2/ respectively, But thao among area and zones were apparently differences.

• 한국패류학회지
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• 제8권1호
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• pp.1-20
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• 1992

A study on the seasonal changes of the benthic macroinvertebrate community was performed on the intertidal rocky shores ao eastern coast of Cheju island and U-do throughout four seasons from october 1991 to August 1992. The macroinvertebrates were composed of 10 phyla, 18 classes, 39 orders, 94 families and 201 species. the number of speecies were 183 in summer, 147 in autumn, 138 in spring and 94 in winter, respectively. The total wpecies collected throuhout the study period were 193 species in U-do and 151 species in the eastern coast of Cheju Island. Nodilittorina exigua was the most dominant species in all seasons, followed by Monodonta neritoides in spring, autumn and winter, and pollicipes mitella in summer. U-do was higher in species diversity and richness and lower in evenness than the eastern coast. Species diversity and richness were higher in summer than any other seasons in lower intertidal zones. Community dominance indices, however, were significantly higher in upper intertidal zones than in lower intertidal zones.

• 아시안잔디학회지
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• 제9권3호
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• pp.225-234
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• 1995

The Widespread and most abundant grasses are Miscanthus sinensis and Pteridium aquilinum in the grassland of Cheju-Island. The vascular flora of the grassland are composed of 127 species in all. Those communities of Miscanthus sinensis Pteridium aquilinum Imperata cylindrica Themeda japon-ica and Zoysia japonica are relatively homogeneous. Standing crops of the mixed grass communities range from 657 g /$m^2$ to 2, 975 g /$m^2$ on August 30, and the value of daily net production is around 2.6~121 g/$m^2$. The standing crop of north facing slop showed higher than that of south facing slop. Relationship between the standing crop and water content, organic matter, total nitrogen and available phosphorus of soils in Cheju-Island showed high level of significant.

• 한국대기환경학회지
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• 제15권6호
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• pp.727-738
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• 1999

Total 76 aerosol samples were collected at Sungsan in Cheju Inland by high volume air sample for 1 year, from May 1995 to April 1996, and were analyzed for major elements(Na, Mg, Ca, Al, Fe) and trace elements(Mn, Co, Ni, Zn, Cd, Pb, U) by ICP/AES and ICP/MS. This study aims to determine the concentrations of trace metals and their seasonal variations in the atmosphere of Cheju Island, where is the remote area from pollution sources and also is the midway of transport of Asian continental materials into the western North Pacific. The concentrations of Na and Mg contributed by sea-salt aerosols were similar to those in the western part of Cheju island(Kosan) and in the western coast of Korea(Mallipo). They showed the highest value in summer and the lowest in spring and winter. Crustal metals(Al, Fe, Ca, Mn, Co, U) were 2~3 times lower than those of Mallipo. These metals showed the lowest values in summer and the highest in spring. Pollution-derived metals (Zn, Cd and Pb) were 2~4 times lower than those in Malipo. Some elemental ratios in aerosols grouped by three wind directions(north-northwest, east, and south-southwest) such as Fe/Al and Pb/Zn are presented as useful tracers indicating source areas, and their differentiation may be explained by geology and fuel types of source areas.