• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.400-401
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• 2000

국내에서 적조연구는 국립수산진흥원에서 남해를 비롯 우리나라 연안의 모니터링과 한양대학교 연구팀의 마산만에 관한 연구가 초기부터 활발하게 이루어졌다. 적조 연구는 주로 적조원인 플랑크톤의 발생규모, 계절적 변동과 그 때 수질환경을 조사하였고 대체로 군집 수준에서 다루어졌다 (박과 김, 1967; 유와 이, 1976; Yoo and Lee, 1979; 박, 1982). 우리나라의 적조 연구는 주로 마산-진해만애서 이루어져 왔다. 마산만과 진해만을 비롯 행암만, 덕동만, 진동만, 칠천수로 등이 그 대상지가 되었으며 이 지역에서는 그동안 상당한 자료가 축적되어 왔다. 하지만 본 연구 대상지역인 광양만에서 적조연구에 관한 자료가 미흡하여 본 연구는 기존의 적조생물의 군집 수준의 연구와 유사하다. 개체군의 변동을 파악하는데 중점을 두었고 광양제철소를 중심으로 하여 남해 일대에 걸쳐 모니터링을 하고 수환경의 특성과 개체군 변동을 동시에 조사함으로서 제철소 건립 후 광양만에서 적조 발생의 최근적조 양상을 분석하였다. (중략)

• Korean Journal of Plant Taxonomy
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• v.35 no.3
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• pp.161-174
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• 2005

In order to presume the relationships between two species of P. ternata and P. tripartia, and their populations of the Korean Pinellia, RAPD analysis was performed. The length of the amplified DNA fragments ranged from 300 to 2,500bp. Seventy scorable RAPD makers were found from the PCR reactions with 7 random oligoprimers and were analyzed by Nei-Li's genetic coefficient. Also, some regional groups instead of same taxa were clustered from the phenogram of UPGMA analysis and NJ tree. Populations within each species were clustered at low genetic distance, there had the closed relationship. According to the regional individuals, Pinellia ternata was showed the variation pattern of morphological (leaf shape and flower color) and cytological characters(somatic chromosome numbers). So we suggested to difference of characteristic variety based on variety of habitat. According to this study, new species (Pinellia sp.) was affiliated with Pinellia and had the closest relationship with Hallasan and Japan population. The RAPD data was very useful to define the genetic variation and to discuss the relationships among the intraspecific taxa and their populations of the Korean Pinellia.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.11a
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• pp.81-81
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• 2002

• Korean Journal of Environment and Ecology
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• v.34 no.1
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• pp.18-26
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• 2020

Echinosophora koreensis (Nakai) Nakai an endemic plant with limited distribution in some parts of the Korean Peninsula, is designated as "Endangered" species on the IUCN Red List. The species is under the threat of deterioration in nature due to various environmental changes causing loss of natural habitats. We investigated the distribution pattern and population structure of E. koreensis to serve as a basic reference for identifying the dynamics and persistence of natural populations of this species in the future. To determine the characteristics of the E. koreensis population, we laid two to three large plots sized 20m×30m on the ridgeline as the reference in Yanggu, Chuncheon, and Hongcheon and laid four to seven small quadrats sized 1m×1m on the transect. A total of 530 plots were laid, 10 each at 2m interval, to measure the number of the stems, the number of fruiting, height, and other factors. The collected distribution information was compared with the existing IUCN assessed categories by applying IUCN Red List ver 3.1 Criteria B. The average population density of the three surveyed areas was 3.47 stem/㎡; the density of each area was 3.95 stems/㎡ in Yanggu, 3.37 stems/㎡ in Chuncheon, and 2.87 stems/㎡ in Hongcheon. The number of fruiting per stem was 0.0038, indicating only 7 fruits out of 1,837 stems and that vegetative reproduction is likely to be more dominant than sexual reproduction. The distribution tendency of population density in the small plots in three surveyed areas showed that the density of E. koreensis tended to decrease toward the center of the forest with low crown openness and around the mountain ridge with high crown openness. It indicated that the quantity of light could be a very important factor for the growth of individuals of this species. The analysis of the heights of individuals present in the surveyed plots showed a range of 2.3 ~ 68.5cm and an average of 20.1cm. An analysis on the stage-structure of the E. koreensis population based on the sieve height found that the appearance frequency decreased with increasing height above 15 ~ 20cm and that the percentage of individuals lower than 10cm, which were presumed to be seedlings, was severely low, indicating a necessity of study on the population sustainability based on the monitored data. The occupied area calculated with the collected species distribution information was 200㎢, indicating the EN category according to the IUCN Red List Reference B.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.411-421
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• 2017

Understanding the need for temperature regulation, behavior, and ecology of hibernating bats provides the possibility of conservation and management for target species. Our objective in this study was to improve understanding of the population trend and ecological requirement in Myotis formosus population in South Korea. From 2007 to 2016, total of 58 hibernacula for Myotis formosus were found across the country. Of the 58 hibernating sites of Myotis formosus, 86% (n=49) were abandoned mines and 14% (n=8) were natural caves. During the survey period, 28 (5%) bats of total 570 bats were observed in natural caves (n=8) and 542 (95%) bats were observed in abandoned mines (n=49). The internal environments of hibernacula of M. formosus were highly stable despite dramatic variation in the external environment. Specifically, we examined the population trend of the endangered bat Myotis formosus in South Korea by long-term monitoring for hibernation sites. The population trend of endangered species M. formosus showed a marked stable in hibernating population. Our results indicate that a tightly collected long-term data set may help to establish the initial approximation of population trends and manage to threats for the endangered bat species.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.10-16
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• 2011

This study was carried out to analyze the vegetation and soil characteristic, and ordination of the Ilex cornuta population, in the Yongsu Reservoir of Jeju Island. The Ilex cornuta population was classified into Cudrania tricuspidata dominant population, Sageretia theezans dominant population, and Mallotus japonicus dominant population. In the study sites, soil organic matter(O.M.), total nitrogen(T.N.), available phosphorus($P_2O_5$), changeable potassium, changeable calcium, changeable magnesium and soil pH were 14.62~17.35%, 0.39~0.51%, 8.83~20.15mg/kg, 0.44~0.64cmol+/kg, 5.79~6.87cmol+/kg, 3.43~4.19cmol+/kg and 5.41~5.80, respectively. The Mallotus japonicus dominant population was mainly found in the high percentage of available phosphorus, organic matter. It was also showed the lowest concentration of exchangeable K, and Mg. Cudrania tricuspidata dominant population and Sageretia theezans dominant population were found in the low percentage of available phosphorus, organic matter and there were also showed the highest concentration of exchangeable K, and Mg. It is one of the evidence that Ilex cornuta community indicated an intensive site management likes clearance of creeper is proper habitat management protocol. Thus, further researches should be followed to determine the other disturbance factors as management techniques.

• Journal of Life Science
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• v.21 no.7
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• pp.1009-1015
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• 2011

Web structure of spiders is a foraging strategy as well as an investment to get prey. In order to increase the fitness consequence, spiders change their foraging strategy based on sensory information provided by prey species. We conducted an experiment to demonstrate whether an orb-web building spider, Argiope bruennichi modifies its web-building behavior after experiencing sensory information emitted by a UV recognizing flying insect, Bombus terrestris. To know how the web structure would be modified, we observed web characteristics after providing sensory information of a potential prey species, the bumblebee (experimental group) and compared them to the control group (no information provided). We hypothesized that the spiders of the experimental group would increase investments in their web construction and stabilimentum decoration. The results rejected our hypothesis. Web and stabilimentum constructions decreased in the course of the experiment in both the control group and the experimental group. The individuals did not increase their stabilimentum length and did not extend their web areas, in spite of sensory information given by the nectar collector.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.257-264
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• 1991

Studies on the geographical distribution and the seasonal prevalence of chigger mites, with particular reference to L. paflidum, a vector species of tsutsugamushi disease were carried out during the period of July 1989-October 1990. From total 111 field rodents collected during the study period, 4,498 chiggers were obtained and 12 species of 4 genera were identified. L. paflidum, the vector species was the dorninant species, showing 65.6% of the total chiggers. L. scutellare, known as the important vector species of tsutsugamushi disease in Japan was not found in the study area, except Yesan-gun, Chungcheong-namdo where only one specimen was collected. The distribution of chigger mites was clearly localized by species, showing the different dominant species by locality. The population density of L. paflidum was high at two study areas, moderate at one area and very low at six other areas, compared to the other species. The study on seasonal prevalence of L. paflidum population density resulted that they started appearing in September (9.8%), showed the peak in October (45.4%) and November (30.6%), almost disappeared during the period of December-March (1.3-0%), reappeared in April (12.7%) showing a small peak, and again almost disappeared until September. L. palpafe was appeared only in winter and spring (December-April).

• Journal of Aquaculture
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• v.22 no.1
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• pp.16-22
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• 2009

Life history of Korean crayfishes Cambaroides similis (Koelbel) was studied 8 month from March to October, 2006 from the Gwanak mountain, Seoul, South Korea. By capture and recapture method, 551 crayfishes were collected analyzed during the experimental period. Based on the distribution pattern of body lengths, the local population putatively divided into four age groups. The sex ratio of male and female was almost equal. However, their growth rates varied by water temperature. Early juveniles seen during June became adult during August. The study findings suggest that late autumn is mating season.

• Korean Journal of Ecology and Environment
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• v.47 no.3
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• pp.160-166
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• 2014

This study was aimed at looking into the distribution status and age structure of Abies holophylla population in Sudo-Am temple forest. It was found that a total of 302 individuals of Abies holophylla existed which were more than 2m in height within the study area. Furthermore the population size is one of the largest in the southern region of Korea. The CBH of Abies holophylla ranged from 1.5 cm to 500.8 cm. Age structure of Abies holophylla looks like a gourd-shaped bottle. This means that they have an unstable structure status and do not survive very long. This status results from a variety of factors including, vegetation succession, anthropogenic activities, and global warming. The environmental characteristics of Abies holophylla population was $931{\pm}64.5m$ in mean altitude, $19.2{\pm}8.7^{\circ}$ in mean slope in the northeastern and southeastern area of the slope direction, and $1,324,323{\pm}174,459wh\;m^{-2}$ in average of direct normal irradiation. Among the site environmental factors, the significant ones which influence the potential habitat for Abies holophylla distribution were chosen using the MaxEnt model. According to the results of this study, altitude and slope were found as the important factors. The average value of environmental conditions by ROC analysis were altitude 903.2 m, slope $20.04^{\circ}$, irradiation $1,352.248wh\;m^{-2}$, and the southeastern aspect.