• Ocean Science Journal
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• v.43 no.4
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• pp.209-222
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• 2008

To understand physical structures in the Korean waters, we investigated the spatio-temporal distribution of Pontella species known as indicator species of water mass using a David-Hempel neuston net from April 2002 to March 2003. Five Pontella species (P. chierchiae Giesbrecht, P. fera Dana, P. latifurca Chen and Zhang, P. securifer Brady and P. sinica Chen and Zhang) were found. Their abundance increased from May to October with increasing the surface water temperature. Pontella chierchiae predominantly appeared in the whole areas while P. latifurca scarcely occurred in coastal waters. The other three species (P. fera, P. securifer and P. sinica) were rarely found in the South Sea of Korea on August to September. We suggest that P. securifer and P. fera as oceanic species can play a role in an indicator species of the Tsushima Warm Current while P. sinica as Chinese coastal species is affected by the diluted waters of the Yantze River. We also provide re-description of the three species (P. chierchiae, P. fera and P. latifurca) insufficiently described and discuss their zoogeography.

• Ocean Science Journal
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• v.43 no.2
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• pp.91-100
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• 2008

The neustonic calanoid copepods Pontella securifer Brady, 1883 and P. sinica Chen and Zhang, 1965 are first recorded in Korea. These species occur in high temperatures over $23^{\circ}C$ and in a range of salinity from 26.6 to 31.2 psu. We provide full descriptions of the two species and discuss their zoogeography.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.461-475
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• 2020

This study was conducted in the southwestern area of Korea using a neuston net in September (14 stations) 2017 to understand the environmental factors affecting neustonic zooplankton. Temperature, salinity, chlorophyll a concentration, suspended solids, and microplastics were included as environmental factors. Based on the density of the copepods, the study area was divided into three regions: the Seomjin River water influence area, the frontal mixing area, and the warm water affected area (Jeju warm current and Tsushima warm current). In the latter two areas, the major species were Pontella chierchiae, Canthocalanus pauper, and Oncaea spp. Also, neustonic zooplankton showed a significant relationship between the density of phytoplankton and microplastics in the frontal mixing area, and temperature and suspended solids in the warm water affected area, respectively (p<0.05). This indicates that microplastics can affect the offshore zooplankton community.

• 한국해양학회지
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• v.15 no.1
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• pp.17-33
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• 1980

The materials were obtained in the eastern Gulf of Alaska and the south- eastern Bering Sea during the cruise of the research vessel, Ohdae San, from July to October 1978. A total of 76 samples were taken by NORPAC net from a depth of 200 meters or less in coastal areas. 1. The surface water temperature in the coastal waters, varing from 9 to 10$^{\circ}C$, was lower than that in offshore waters which varied from 10 to 12.9$^{\circ}C$ in the eastern Gulf of Alaska. Thermocline was formed in the 30∼50 meter layer. Salinity of the coastal waters of Kenai Peninsula and Kodiak was 30 which was slightly lower than that of offshore. 2. The water temperature of the surface layer down to 30 meters varied from 7 to 10$^{\circ}C$ and from 1 to 9$^{\circ}C$ in the layer below 30 meters in the south-eastern Bering Sea. Meandering thermal front spread from the Alaska Peninsula to St. Matthew Island by way of St. Paul, and a thermocline was found at the 30∼50 meter layer Salinity ranged from 31.0 to 33.0 and that of northern and coastal waters was little lower than that of offshore. 3. Zooplankton biomass fluctuated from 0.1 to 23.6cc/10㎥ in the eastern Gulf of Alaska and 2.0 to 26.1cc/10㎥ in the south-eastern Bering Sea. Plankton was rich in the following areas, the inshore Kodiak waters, the northern Bering Sea, the Coastal waters and waters adjacent to Alutian islands however, poor in the central Bering Sea. In general, the south-eastern Bering Sea has a higher concentration of plankton volume than the eastern Gulf of Alaska. 4. Twenty three species representing 17 genera of copepods were identified from the samples. These were mostly composed of the cold water species, such as Pseudocalanus minutus, Acartia longiremis, Metridia lucens and Eucalanus bungii var. bungii. 5. The cold oceanic species were composed of Calanus cristatus, C.plumchrus, Metridia lucens, Eucalanus bungii var. bungii and Scolecithricella minor. The cold neritic species were Centropages abdominalis, Pseudocalanus minutus, Acartia longiremis, Eurytemora herdmanii, Pontella pulvinata, P. longipedata and Tortanus discaudatus. On the other hand, the warm oceanic species were Calanus tenuicornis and Oithona plumifera. The cosmopolitan species were Calanus finmarchicus and Oithona similis. 6. It was suggested that the cold oceanic species, Eucalanus bungii var. bungii and Metridia lucens in the south-eastern Bering Sea can be recommended as a valuable indicator species for finding the fishing grounds of demersal fish such as pollock and yellowfin sole in this area.