• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1456-1462
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• 2008

This study conducted a direct shear test to evaluate friction properties on contact surface of waste resources including turban shell, gastropod shell and PET bottle film. The contact surface that was considered for computation of shear strength in contact surface were turban shell/turban shell, gastropod shell/gastropod shell, and PET bottle film/PET bottle film. As a result of test, friction angle was found to be $16.7^{\circ}$ for contact surface of turban shell/turban shell, $35.4^{\circ}$ for gastropod shell/gastropod shell, and about $11^{\circ}$ for PET bottle film/PET bottle film. Using the results, the author aims to provide a possibility for application of waste resource in the field.

• Journal of Ecology and Environment
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• 제29권5호
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• pp.453-460
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• 2006

Upo wetland is the largest inland wetland in Korea as Ramsar Convention Area. The purposes of the study were to investigate the levels of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the sediment and Cipangopaludina chinensis malleata from three sites of the wetland and to assess the potential of the gastropod as a bioindicator for heavy metal levels. The gastropods were dissected into shell and soft tissue without the digestive and excretive organs. The levels of Cd, Cu and Pb were below the guideline of Soil Environment Conservation Act and the heavy metals except Cr were slightly different among the sites. Cd was higher in Upo site ($0.32{\mu}g/g$) than Sajipo site ($0.28{\mu}g/g$). Cu and Zn showed the highest value in Sajipo as $43.5{\mu}g/g\;and\;39.8{\mu}g/g$, respectively while the concentrations of Pb and Zn were the highest in Upstream as $58.8{\mu}g/g\;and\;138{\mu}g/g$, respectively. In the soft tissues and shells of the gastropod, the overall common trend in the concentrations of the heavy metals was revealed with the following order: Zn > Cu > Cr > Ni > Pb > Cd and Ni > Zn > Cr > Cu > Pb > Cd, respectively. Although the soft tissues exhibited higher concentrations of the heavy metals except Ni than the shell in the gastropod, the levels of Cd and Pb in the gastropod were generally below the restrictive values set up by Korea Food & Drug Administration. From Duncan's Multiple Range Test (DMRT) results, the concentrations of Pb and Zn in the sediments among the sites were reflected on the soft tissue (Pb) and the shell (Pb and Zn) of the gastropod in the same order. The lower value of coefficient of variation (CV) in Pb concentration of the shell than in that of the soft tissue supports the usefulness of the shell as a bioindicator for Pb pollution. Although the CV value in the shell was a little higher than in the soft tissue, DMRT results and the stability of incorporated Zn into the shell support the use of the shell of the gastropod as a potential bioindicator for long-term contamination of Zn.

• Animal Systematics, Evolution and Diversity
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• 제37권3호
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• pp.187-204
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• 2021

Three new copepod species of Anthessius are described as associates of mollusks. Anthessius tuberculatus n. sp. associated with the bivalve Asaphis violascens (Forsskal in Niebuhr, 1775) in Kosrae, Micronesia bears a pair of dorsal tubercles on the fifth pedigerous somite. Anthessius rarus n. sp. is associated with the aplysiid gastropod Dolabella auricularia (Lightfoot, 1786) in Bohol, the Philippines and has elongate caudal rami which are about 5.2 times as long as wide. Anthessius cucullatus n. sp. associated with the aplysiid gastropod Aplysia kurodai Baba, 1937 in Korea has a hood-like dorsal expansion on genital double-somite of the female.

• 한국지반환경공학회 논문집
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• 제9권5호
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• pp.53-59
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• 2008

본 연구에서는 대형직접전단시험을 이용하여 조립재료와 지오신세틱스 사이의 접촉면 마찰특성을 비교하여, 조립재료인 고둥껍질과 쇄석간의 조립재료특성을 파악하여 고둥껍질의 효용성을 높이는데 그 목적이 있다. 이 연구를 위하여 모형지반을 조립재료인 쇄석 또는 고둥껍질로 형성하여 부직포 또는 지오스트립 지오신세틱스를 포설 전단시켜 마찰계수와 마찰각을 비교 분석하였다. 분석결과 쇄석의 단위중량이 $13.7kN/m^3$ 일 때 $33.8^{\circ}$, 고둥껍질의 단위중량이 $5.4kN/m^3$ 일 때 $35.4^{\circ}$의 내부마찰각을 나타내었다. 또한 지오신세틱스와 쇄석의 접촉면 마찰각이 지오신세틱스와 고둥껍질 접촉면 마찰각보다 크게 나타났다.

• Journal of Ecology and Environment
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• 제48권1호
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• pp.60-73
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• 2024

Background: The available information on terrestrial pest gastropods and their impact on the environment worldwide is scarce and outdated. The present study aimed to address this gap by conducting the first comprehensive survey of pest gastropods in the Nuwara Eliya District, an important vegetable growing area in the highlands of Sri Lanka. Eighty agricultural lands were surveyed over two years by establishing ten 1 m2 sampling plots per crop type in each agricultural land. Geo-coordinates, air temperature, elevation, relative humidity, daily rainfall, soil pH, species richness and abundance were recorded for rainy and non-rainy periods. The relationship between species composition and environmental variables was analyzed using multi-regression models and distribution maps. Results: Out of the 14 species recorded in agricultural lands, nine were identified as exotic pest species. Species abundance (t = 4.69, p < 0.05) and diversity was higher in the rainy period and the dominant species during this period were Bradybaena similaris (t = 2.69, p < 0.05) and Deroceras reticulatum (t = 2. 46, p < 0.05). Eggs and estivating adults were found in soil and under decaying organic matter during the non-rainy period. The exotic species showed broader preferences for the measured environmental factors and showed a wider range in distribution compared to the native species. Variation in pest gastropod composition was significantly accounted for by elevation, relative humidity, soil pH and daily rainfall. Additionally, the species richness and abundance varied across locations due to the combined effects of elevation, crop type and stage, and field type. Conclusions: The study emphasizes the importance of understanding the biology and ecology of gastropod pests to develop effective management strategies. By considering the influence of environmental factors and implementing appropriate soil management techniques, such as targeting specific habitats and crop stages, it is possible to mitigate pest populations and minimize their impact on agricultural lands. Overall, this research contributes valuable insights into the dynamics and interactions of terrestrial gastropods in agricultural ecosystems, supporting sustainable pest management practices.

• Parasites, Hosts and Diseases
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• 제50권2호
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• pp.177-180
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• 2012

Cercaria caribbea LVIII Cable, 1963 (Digenea: Cyathocotylidae) was detected from a brackish water gastropod species (Cerithideopsilla cingulata) in a coatal area of Shinan-gun, Jeollanam-do (Province), the Republic of Korea, and its surface ultrastructure was studied using a scanning electron microscope. The cercariae were found freely swimming or enveloped within daughter sporocysts when the snail host was mechanically broken. They were morphologically characterized by a linguiform and ventrally concave body, a long and bifurcated tail, and the presence of a holdfast (=tribocytic) organ posterior to the ventral sucker. On the whole ventral and dorsal surfaces, peg-like tegumental spines were densely distributed. Around the oral sucker, several sensory papillae, each with a short cilium, were distributed, and on the tail, sensory papillae, each with an extensively long cilium, were observed. This is the first record describing a cyathocotylid cercaria from a brackish water gastropod in the Republic of Korea.

• 자원환경지질
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• 제38권2호
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• pp.129-134
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• 2005

수중생물과 그 생물이 살았던 물과의 Sr 동위원소 조성은 크게 다르지 않으나, Pb 동위원소비는 Sr 동위원소와는 달리 생물과 그 생물이 살았던 물과 상이한 값을 보인다. 이 두 동위원소를 환경추적인자로 동시에 적용할 목적으로 담수에 사는 수중생물인 다슬기(Semisulcospira libertina) 껍질의 두 동위원소비를 측정하여 보았다. 하천수에 사는 다슬기 껍질의 Sr 동위원소비는 그들이 살았던 하천수의 동위원소비와는 같은 값을 보이지만, 채취지역에 따라서는 다른 값을 가진다. 하천수의 Sr 동위원소조성이 다른 것은 각 하천수의 기반암의 Sr 동위원소가 서로 다르기 때문으로 결국 하천수중의 Sr은 기반암으로부터 유래하고 다슬기 껍질의 Sr은 하천수에서 기인한 것으로 볼 수 있다. 반면에 Pb 동위원소비는 하천수와 다슬기 껍질이 서로 다른 값을 보이는 것은 하천수에 용해된 Pb이 다슬기가 흡수 가능한 Pb과는 다른 것으로 생각되며, 다슬기 껍질의 Pb 동위원소비는 강우의 Pb 동위원소비와 유사하다. 하천수에 용해된 Pb은 기반암에서 유래한 것이 아니라 토양 중에 집적된 대기기원의 Pb이 대부분인 것으로 생각된다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.79-80
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• 2003

In order to develop an indoor assistive mobility equipment, we paid attention to the mechanism of locomotion in a snail, or a terrestrial gastropod molluscs. It is known that the snail moves by propagation of a pedal wave generating on a pedal surface of the snail and a pedal locomotion has flexibility far ground condition. An air mattress with a function of a pedal-like locomotion mechanism was developed and the performance of the pedal locomotory air mattress as mobility equipment was discussed.

• Ocean and Polar Research
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• 제24권3호
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• pp.215-223
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• 2002

Symbiosis of chemoautrophic bacteria with the members of hydrothermal vent and cold seep communities in the deep-sea were examined by histology using transmission electron microscopy; Bathymodiolus spp. from Sagami Bay, the Iheya Ridge and the North Fiji Basin; and Ifremeria nautilei from the North Fiji Basin. Two species of Bathymodiolus, each from Sagami Bay and the Iheya Ridge harbored methane-oxidizing symbionts within their gill tissues. Vent gastropod Ifremeria nautilei from the hydrothermal vents of the North Fiji Basin housed two types of symbionts; one sulfur-oxidizing type and the other methane-oxidizing type. The occurrence of chemosynthetic symbionts in these organisms were expected before-hand based on the ecological observations of their habit. The other members of these groups from world oceans and the recent advances in the symbiosis of the vent and seep communities were reviewed.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.531-532
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• 2000

The morphology of molluscan egg capsule is generally regarded as being species specific (Turner, 1992), and form and structure of the egg capsule reflect the degree of anatomical complexity of the reproductive organs (Fretter ＆ Hian, 1984). Ceratostoma rorifluum and Ocinebrellus inornatum are common and widespread muricid species found throughout the Korean rocky and boulder shores, and Neptunnea constricta is found frequently from continental shelf of the eastern sea of Korea. In spite of their predominance along the Korean coasts, morphology of their eggs and egg capsules is unknown so far. The purpose of the present study, therefore, is to provide descriptions and illustrations for identifying egg capsules of the foregoing 3 stenoglossan gastropod species. (omitted)