• Korean Journal of Weed Science
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• v.3 no.2
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• pp.117-119
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• 1983

• Journal of Environmental Science International
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• v.23 no.9
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• pp.1563-1572
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• 2014

The autecology of the Zostera marina and Z. japonica was studied in populations growing in the same locality (Sagumi Bay, southwestern coast of Korea). Environmental factors and plant characteristics were examined monthly from August 2008 to September 2011. Along intertidal zone, Z. japonica (0.1-0.5 m above mean lower low water, MLLW) occurred above Z. marina (0.5-2.5 m MLLW). Tidal exposure at low tide during day was the highest in the spring and the lowest in the summer. Underwater Irradiance showed seasonal fluctuation that was the highest in spring and summer caused by tidal pattern. Strong seasonal patterns in water temperature appeared to control the seasonal variations in morphology, biomass and leaf growth. The seasonal pattern of Z. japonica resembled that of the Z. marina in morphological characteristics, above-and below-ground biomass, whereas it differed in shoot density and leaf elongation. Despite some similarities in seasonal growth patterns, the patterns of Z. japonica were lagged by 2 month of Z. marina. Seasonal variation in the above biomass of Z. marina was caused by changes in density and plant size, whereas that of Z. japonica was mainly caused by changes in shoot density. Zostera marina was more sensitive to high temperatures than Z. japonica, and the increasing water temperature during the summer became the factor that inhibits the growth of the Z. marina. Zostera Japonica, there is no clear change according to the amount of the light. It is because its habitat locates above that of Zostera marina so that the amount of the light that is necessary to growth is enough and in this condition, any preventing factor does not seem to work at all. Although underwater light getting into Zostera marina's habitat is very low level and there is no any hindrance to the survival of them, it prevents them from their productivity a bit.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.285-298
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• 2014

The present study summarizes the occurrence, distribution and autecology of the genus Micrasterias Ralfs among desmids collected from several swamps, reservoirs, rivers and high land wetlands in South Korea from 2009 to 2013. In total 21 taxa of Micrasterias including three new species, Micrasterias spinosus sp. nov., M. jejuensis sp. nov. and M. koreanus sp. nov., were identified. In this study, photomicrographs of all of these are provided and briefly discussed with regard to their taxonomy, distribution and ecology within South Korea.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.339-346
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• 2013

The present study summarized the occurrence, distribution and autecology of 18 taxa in the class Euglenophyceae collected from several swamps, reservoir and mountain wetlands in the South Korea from 2009 to 2013. This paper deals with 18 taxa consisting of 3 taxa of Colacium Ehrenberg, 2 taxa of Phacus Dujardin, 13 taxa of Trachelomonas Ehrenberg, which are recorded for the first time in Korean freshwater algal flora.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.303-314
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• 2013

The present study summarized the occurrence, distribution and autecology about 31 taxa of the green algae (Chlorophytes) collected from several swamps, reservoir and highland wet-lands in the South Korea from 2010 to 2013. This paper deals with a total 31 taxa including of 26 genera which are recorded for the first time in Korea. Among these algae, 18 genera including Pyrobotrys Arnoldi, Volvulina Playfair, Dicellula Svirenko, Echinocoleum Jao & Lee, Hofmania Chodat, Gloeotila Kutzing, Tetrachlorella Korschikov, Botryospherella P.C.Silva etc., were newly recorded in Korean fresh-water algal flora.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.293-302
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• 2013

The present study summarizes the occurrence, distribution and autecology of 12 taxa of the class Cyanophyceae collected from several swamps, reservoir and highland wetlands in South Korea from 2009 to 2012. A new species, Anabaena koreana sp. nov. and 11 taxa of blue-green algae newly recorded are described and illustrated. Anabaena koreana is similar to A. oumiana, A. spiroides and A. crassa in that the trichomes form regular coils. However, A. koreana is distinguished from these three species by the morphological characteristics of the vegetative cell, heterocyst, and akinet shape and size. This study considers 12 blue-green algal species, including a new species, Anabaena koreana sp. nov. and 11 species that are recorded for the first time in the Korean freshwater algal flora. Among them, the genus Nostochopsis Wood ex Bornet et Flahault 1886 had not previously been recorded in Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.129-133
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• 2002

본 고에서는 지하 대수층 생태계 및 그에 대한 외국의 연구사례를 개괄하여 소개하고, 지속가능한 지하수 개발에 있어서 대수층 생물이 갖는 의미에 대하여 고찰하였다. 아울러 국내에서 발견된 대수층 생물을 소개하고 향후 연구방향을 설정하였다. 지하 대수층은 다양한 생물로 구성된 독특한 생태계를 가지고 있다. 생물학적 평형상태를 유지하는 경우 이 생태계는 대수층이 장기간 양호한 수질을 유지할 수 있는 기능을 가진다. Parabathynellidae, Parastenocaris 및 선충류의 발견을 통해서 고령군 다산면 대수층이 지하수 생태계 연구를 위한 적합한 대상임이 확인되었다. 향후 연구방향으로서 1) 지하수 동물상 조사, 2) 생태계 구성원에 대한 Autecology 및 Synecology적 접근, 3) Bioremediation 및 Bioindicator 관련 연구 등이 제시되었다.

• ALGAE
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• v.22 no.4
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• pp.287-295
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• 2007

Infection of free-living dinoflagellates by endoparasitic dinoflagellates of the genus Amoebophrya are thought to have significant impacts on host population dynamics and have long been proposed to be a potential biological agent for controlling harmful algal bloom (HAB). To understand the impact of Amoebophrya on particular host species, however, it is necessary to quantify aspects the parasites life cycle. Here we used cultures of Amoebophryahost systems from Jinhae Bay, Korea to determine, parasite generation time, and dinospore survival and infectivity. The proportion of host cells infected by Amoebophrya sp. changed sharply from 5% to 87% with increasing dinospore:host inoculation ratios. In the absence of H. triquetra, most free-living dinospores died within 72 hours and their ability to infect host cells decreased remarkably in a day. The relatively short free-living phase of Amoebophrya suggests that the spread of infections is most likely to occur during seasons of high host abundance, as that is when dinospores have the greatest chance of encountering host cells. Infection of host cells inoculated with dinospores during the day was higher than when inoculated during the night, suggesting that infection rates might be related to environmental light conditions and/or diurnal biological rhythm of host species. Total generation times of parasite strains from a thecate dinoflagellate Heterocapsa triquetra were nearly the same regardless of dinospore:host inoculation ratios, representing 54 ± 0.5 h in a 1:1 ratio and 55 ± 1.2 h in a 20:1 ratio. Dinospore production of Amoebophrya sp. infecting Heterocapsa triquetra was estimated to be 125 dinospores per a strain of Amoebophrya sp. There is a growing need to maintain a variety of host-parasite systems in culture and to examine their autecology under various environmental conditions. Such studies would be very helpful in understanding ecological role of these parasites, their overlooked importance in the flow of material and energy in marine ecosystem, and their practical use as biological control agents applied directly to areas affected by HAB.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.381-386
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• 2013

The increased $CO_2$ concentration and temperature affect ecological responses of plants. In order to know the effects of global warming on the Viola raddeana Regal, endangered aquatic plant designated by the Ministry of Environment Korea, this study was investigated at control and treatment(increased $CO_2$ concentration + increased temperature) in glasshouse. Then, autecological responses of V. raddeana were monitored and measured. As a result, shoot length, number of fruits per plant, number of branch per plant, number of seeds per fruit, number of fruits per branch, and weight of 10 seeds were higher in control than in treatment. number of leaves per branch was higher in treatment than in control. Length of axis, length of branch and number of leaves per plant were not different between in the control and in the treatment. These results demonstrated that the reproductive response of V. raddeana might be negatively influenced by increased $CO_2$ concentration and temperature. The global warming will be one of the main causes of extinction for V. raddeana Regal.