• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.553-558
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• 2010

This study was conducted to clarify the differences in rodents population densities between natural restored and red pine silvicultured forests after forest fire in Samcheok, Gangwon Province, Korea from March to December 2008. One ha size of 3 study plots were set up in each natural restored and silvicultured stand. We trapped the small rodents during 4 consecutive nights every 2 months in each stand. Understory coverage and number of shrub stems were higher in silvicultured stand than in natural restored stand. Coverage of overstory, suboverstory and midstory, number of tree stem, woody seedling stems and dead wood, and amount of coarse woody debris were higher in natural restored stand than in silvicultured stand. Six hundred eighty eight individuals of four species, such as Apodemus agrarius, A. peninsulae, Eothenomys regulus and Tamias sibiricus were captured in our study. Number of captured small rodents were higher in natural restored stand than in silvicultured stand. Also, species compositions were differed in both stands. The captured number of A. agrarius and A. peninsulae were most highest in April and December. E. regulus were shown higher number of captured in April and June, and T. sibiricus were in June and October. Removal of coarse woody debris and silvicultural practice would not be good for the inhabitation of small rodents. For the conservation of small rodents diversity, management of understory and canopy would be needed in forest fired area.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.50-50
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• 2016

하천에서 유사 및 오염물질의 이동을 예측하기 위하여 초점을 두는 것에는 두 가지 요소가 있다. 입자의 농도로 나타낼 수 있는 양의 개념과 입자의 위치로 나타낼 수 있는 공간의 개념이 그것이다. 유사 입자와 같이 그 비중이 물보다 큰 경우, 흐름 내에서 침전과 부상의 메커니즘을 반복하게 되는데 최종적으로 바닥에 침적하는 위치는 하상변동, 서식처 등 하천관리의 다양한 측면에서 매우 중요하다. 유사 입자가 바닥에 침적하는 위치를 예측하는 데에는 난류와 지형 같은 많은 불확실한 요소가 내포되어 있어, 같은 크기의 유사 입자라 하여도 하나의 exact point로 도달하지 않는다. 이러한 불확실한 요소를 고려하여 침전 위치를 산정하는 방법에 대한 연구가 필요하다. 따라서 본 연구에서는 침전 위치를 확률밀도함수로 나타내어 분석하고자 한다. 입자의 침전 위치를 확률밀도함수로 나타내기 위하여 입자 기반의 추적 모형을 사용하여 위치 데이터를 얻었으며, 이를 실험데이터와 비교하여 검증 후 확률밀도함수로 나타내었다. 그 결과 입자의 침적 위치에 대한 확률밀도함수는 로그정규분포를 띠고 있음을 확인하였으며, 확률밀도함수를 나타내는 매개변수를 물리 기반 회귀모형식으로 일반화 하여 나타낼 수 있었다.

• The Korean Journal of Ecology
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• v.18 no.4
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• pp.513-513
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• 1995

The central theme of Habital heterogeneity is to provide animals with habital complexity or structural diversity and to allow resource partitioning among individuals. In turn, the leads to population stability because prey can escape more easily with more hiding places causing less population fluctuation. Species diversity is characterized due to more potential niches both horizontally and verticall. Empirically, in homogeneous habitats population was less abundant, reproduction and survival were lower, spacing behavior, competition and dispersal were higher than in heterogeneous habitats. The results imply that diversity and conservation of species can be maintained through providing heterogeneous habitats.

• Korean journal of applied entomology
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• v.15 no.2 s.27
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• pp.89-93
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• 1976

The present report is dealt with the spiders which are caught within a space of $1m^2$ of rice paddy field where was harvested the rice crops in Jeonbug district, from November 4 to 11, to 1975. 1. Twenty-one species of spiders were caught at the area during the period. Of these the dominant species were Gnathonarium dentatum, Pirate subpiraticus, Gnathonarium gibberum, Oedothorax insecticeps etc. 2. Average density of spiders within a space of $1m^2$ of rice paddy field where rice crops was harvested was as follows: 125 at Iri, 102 at Jinan, 133 at Buan, and 58 at Daejang. 3. The scientific names of spiders which were caught in rice paddy field for the first time in Korea were Gnathonarium gibberum, Enoplognatha japonica, Erigone prominens, Erigonidium graminicola, Theridion octomaculatum, Lycosa pseudoannulata, Dolomedes angustivirgatus. As the result of this survey, fifty-five species of spiders were recorded in rice paddy field of Korea.

• Journal of Wetlands Research
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• v.11 no.2
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• pp.99-106
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• 2009

Water spider(Argyroneta aquatica Clerck) is only spider that live under aquatic water. In korea, water spider distributed only in Undari Wetland, Yeochon County, Kyongii Proviance, where it is designated as Natural Monument. I counted the population density, analysed the ecological traits such as actual vegetation map, and suggested conservation strategy and eco-tourism planning for water spider. The population mean density of water spider was one individual/$m^2$ and 8,000 individuals/ha. The wetland inhabited by water spider was characterized by high water level fluctuation between rainy season and dry ones. Wetland plant community was dominated by Phragmites australis and Leersia oryzoides var. japonica with submersed plant, Utricularia japonica. It is need to supply water for inhibiting terrestial succession trend during the dry season and to connect three fragmented wetlands through ecological corridor. Also, It was suggested that ecotourism planning is important for conserving this wetland.

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.282-291
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• 2014

This study was conducted to make distribution model of the Red-crowned Crane and the White-naped Crane according to the anthropogenic and natural factors affecting distribution of crane in Cheorwon, Korea. It was investigated that the impact power and its range of the indirect anthropogenic influence to feeding flock density in cranes from the road, residential area, military facilities, civilian control zone (CCZ), greenhouse and natural influence such as roosting site and available feeding area. Available feeding area is the most important factor for the crane's feeding site selection. The feeding flock density of the cranes near the residential area was lower than that of area far from the area, and tended to increase within 2.5 km distance. The increasing tendencies of feeding flock density from military facilities and high traffic volume road were similar, but the density in military facilities increased within 800 m, and the density from high traffic volume road increased within 2 km. These results suggested that residential area, military facilities and the road with high traffic volume had significant effect on foraging densities to the certain range. As the distance from the road with low traffic volume and roosting site increased, feeding flock density tended to decrease. The density of Red-crowned crane and White-naped crane inside the CCZ were respectively higher than those of outside the CCZ, especially for the Red-crowned crane. As a result, density of Red crowned cranes inside the CCZ was 5.2 times higher than that of outside, while that of white-naped cranes was 2.2 times bigger. If the density of greenhouse is lower than $40km^{-2}$, crane's feeding flock density in the low greenhouses density area was higher than that of high greenhouses density area. However, there was no difference in the feeding flock density if the density of the green houses is higher than $40km^{-2}$. The model for the Red-crowned Crane was related with available feeding area, distance from residential area, civilian control zone and distance from high traffic road. The model of the White-naped Crane was related with available feeding area, distance from roosting site and distance from lake. Finally, the estimated feeding flock density of cranes significantly correlated with density model according to the natural and anthropogenic factors.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.43-55
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• 2004

Meiobenthic community structure was studied in intertidal mud flat and sand flat of Yeochari in Ganghwado in May and August, 1998. Sixteen groups of meiofauna were found at all study sites in the Yeochari tidal flats. Nematodes were the most dominant animal group among the meiofaunal groups as a whole. Sarcomastigophorans, harpacticoid copepods, nauplius larvae of crustaceans and ciliophorans which were also important components of the meiofaunal community. All of these five faunal groups comprised more than 90% of total meiofauna. The maximum total density of meiobenthos was $5.8{\times}10^6ind./m^2$ at the station of sand flat in August and the minimum density was $4.0{\times}10^6ind./m^2$ at same station in May. Biomass of meiobenthos was $1.5g/m^2$(May), $2.3g/m^2$(August) at mud flat and $1.7g/m^2$(May), $2.6g/m^2$(August) at sand flat. At the station of mud flat in May, the highest density was observed within 1cm in depth of upper sediment and steeply decreased increasing depth of sediment. At the sand flat station in August, the highest density was also observed within 1cm in depth of upper sediment and decreased with depth, while the concentration of the animals at the surface was not conspicuous as the mud flat. The value of N/C(nematodes/benthic harpacticoids) ratio was the highest at the station of sand flat in May and the lowest at the sand flat in August.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.4
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• pp.93-99
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• 2007

Vertical distribution of tiger worm(Eisenia fetida) population in the earthworm rearing bed was investigated with feeding paper mill sludge. More than 50% of larva and adult population of Eisenia fetida lived within the depth of 5 cm from the surface of rearing bed. And more than 96% of the population of larva, adult and cocoon lived within the depth of 20 cm. Percental vertical distribution of Eisenia fetida population in the rearing bed was not much influenced by the changes in the height of rearing bed or density of earthworm population.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.371-372
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• 2001

개조개(Saxidemus purpuratus)는 백합목 백합과에 속하는 종으로 우리나라, 일본 북해도 남부부터 九州 및 중국 대륙 연안까지 넓게 분포하고, 조간대부터 수심 40 m의 모래나 자갈이 섞인 진흙에 서식한다(Yoo, 1976). 우리나라에서는 고가의 식용패류로서 경제적 가치가 높은 종이나, 일본의 경우 식용으로 이용하지 않는다. 본 종에 관한 연구를 살펴보면, 우리나라의 경우, 생식세포 및 산란시기에 관한 연구(Chung and Kim, 1994; Chung et al., 1999; Ahn, 2001; Kim et al., 2001)가 많이 이루어져 있고, 식품가공학적 연구(Kang, 1998); Jung, 1992; Oh, 1998; Oh et al., 1998)는 꾸준히 이루어지고 있는 실정이다. (중략)

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.200-206
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• 2017

The damage and fragmentation of habitat due to urbanization pose a great threat to amphibians worldwide. To understand the effect of urbanization on the distribution and abundance of Hyla japonica, we measured their population sizes by listening frog calling and investigated the habitat their population sizes and land use in the 18 rice paddy fields located in Incheon and its surroundings. Abundance of H. japonica was 0 - 17 male adults / habitat or 0 - 41 male adults / ha in Incheon. The number of the frog was increased as the distance between the habitat and the road became longer or the ratio of circumstance / area of the habitat increased. Unlike the general prediction, the density of H. japonica showed a negative correlation with the size of the habitat and a positive correlation with the surrounding land use intensity. Our results suggested that H. japonica could be concentrated in a narrow habitat due to the habitat size decrease and the periphery development according to the urbanizaion.