• Korean Journal of Environment and Ecology
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• v.27 no.2
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• pp.209-218
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• 2013

This study was conducted to analyze the characteristics of odonata communities as habitat types in Wonju City, Korea. The 33 plots were installed at 4 types of biotope like abandoned paddy fields, natural type reservoir, natural type river and forest valley in Wonju city. From the survey, the 9 family and 38 species were identified. As the result of comparative investigation of the species composition of each habitat through TWINSPAN analyzing, the difference of species composition was definite in abandoned paddy field, natural type reservoir and forest valley, however, it was uncertain in natural type river. The dominant species and the subdominant species of each habitat were mainly Sympetrum frequens and Sympetrum infuscatum but the distributions of Paracercion hieroglyphicum, Epophthalmia elegans, and Anax parthenope julius were different as haibtat types. The order of the index of species diversity was not different between abandoned paddy fiedls, natural type reservoir and natural type river, but forest valley was low. The abandoned paddy field was shown the most diverse spawning type of odonata, it is considered that hydrophyten play an important role in the abundant of odonata since the sorts of odonata spawning in plants are majority. As the result of analyzing interspecies relationship, Crocothemis servilia mariannae and Orthetrum albistylum, Crocothemis servilia mariannae-Platycnemis phyllopoda, Lyriothemis pachygastra-Sympetrum parvulum are shown the positive correlation, however, they have a difference in preferred habitat between high correlation species.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.3
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• pp.233-242
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• 2018

This study explored the richness patterns of vascular plant species and evaluated the effects of the climatic and habitat variables on the observed patterns along elevational gradients on the Mt. Baekhwa, South Korea. Plant data were recorded from 70 plots and a total of 187 plant species with 78 woody and 109 herbaceous species were recorded along two study transects, the Banyasa and Bohyunsa transects, on the Mt. Baekhwa. A total of 154 plant species with 66 woody and 88 herbaceous species and 131 plant species with 58 woody and 73 herbaceous species were recorded along the Banyasa and Bohyunsa transects, respectively. We used simple ordinary least squares regression model, multi-model inference and variation partitioning to analyze the relative contribution of climatic and habitat variables on the elevational richness patterns. Species richness pattern for vascular plants along the Banyasa transect monotonically decreased with elevation, whereas plant species richness showed reversed hump-shaped pattern along the Bohyunsa transect. Although the elevational patterns of species richness for vascular plants were different between the both transects, habitat variables are more important predictors than climatic variables for the elevational patterns of plant species richness along our study transects on the Mt. Baekhwa. These results indicate that elevational diversity patterns of vascular plants may be different even between nearby elevational transects in a mountain ecosystem but the diversity patterns may be controlled by same drivers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2B
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• pp.211-217
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• 2010

This paper presents numerical investigations of the physical habitat changes induced by the hydropeaking in the downstream river of dam. For the two-dimensional ecohydraulic simulations, River2D model is used. Pirami (Zacco platypus) is selected as the target fish for investigating the impact of the hydropeaking. For validation of the model, the water surface elevations are simulated with two different water discharges. The computed results are compared with field data in the literature, and the result shows that the model successfully simulates the water flows. The weight usable area (WUA) of Pirami with the life cycle and the composite suitability index with different water discharges are computed and discussed. The results show that habitat for Pirami appears to be best in the bend region downstream of the dam. The discharge of the maximum WUA for adult Pirami is computed to be about 9 $m^3/s$. Also, the WUA computed in a condition of hydropeaking during seven days are presented. The averaged discharge of the hydropeaking appears to be about 20% larger than the drought flow, but the WUA by the hydropeaking is computed to be 60-100% smaller. This result shows that the hydropeaking reduces quantity of habitat available to fish.

• Journal of Ecology and Environment
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• v.34 no.3
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• pp.269-278
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• 2011

Carabid beetle community changes in paddy fields, abandoned paddy fields, and mountains were investigated to understand differences in species diversity and composition of different habitat types in small agricultural landscapes in South Korea. A total of 2,938 individuals from 37 species were identified and classified from the studied habitats. Diversity in the mountains was higher than that in abandoned paddy fields. As the number of years since abandonment increased, the diversity and stability of the carabid beetle community also increased. Abandoned paddy fields in some paddy field areas and adjoining mountainous areas, left with preconditions for management and control, have provided the opportunity to improve the diversity and habitat of small agricultural landscapes. Species composition changed continuously from the paddy fields to the mountains, in accordance with individual species habitat preferences. Abandoned paddy fields in small agricultural landscapes are believed to play an important role as transitional buffer zones between paddy fields and the adjacent mountainous areas.

• Journal of Ecology and Environment
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• v.35 no.2
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• pp.79-89
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• 2012

This study was conducted with the intention of clarifying the effects of land-use types on a species of ground beetle's richness, abundance, and composition; the study focused on urban landscapes. We also selected the potential bioindicators classifying land-use types; eleven sites were selected from an urban landscape in Korea. Overall, land-use types in urban landscapes did not appear to cause significant decrease in species richness or the abundance of total ground beetle assemblage. According to habitat preferences, several land-use types and distances from the forest significantly affected the species richness and abundance, while the open-habitat species were not affected by these variables. Land-use types were classified into two major groups, forest and non-forest areas, based on ground beetle assemblage; several indicators, such as $Dolichus$ $halensis$ $halensis$ and subfamily Carabinae species, were of particular consideration. In conclusion, environmental change by anthropogenic disturbance can cause different effects on ground beetle assemblages, and forest specialists can be negatively affected.

• Fisheries and Aquatic Sciences
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• v.3 no.3_4
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• pp.222-227
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• 2000

Fabrea salina living at salt pond is an interesting ciliate in the research of photobiology and live food for aquaculture. This study was carried out to understand the natural habitat of F. salina at salt pond, which would be a basic biological knowledge for the indoor mass culture of this ciliate. In this research, the water quality as temperature, salinity, dissolved oxygen, and chlorophyll-a was examined with the population density of the ciliate at salt pond. The highest population density of F. salina occurred at 109 ppt and $31^{\circ}C$with 2,390 inds./L in August, and the distribution of the ciliate was positively correlated with salinity, temperature, and chlorophyll­a. Even though F. salina is a very euryharine ciliate, it did not occur at the salinity below 47 ppt in this study. Its reason is able to be explained with the occurrence of many predators as small fish and food competitors as zooplankton living at low salinity of salt pont. While F. salina occurred with Anemia at the same habitat using the same food source, the optimum salinity for the ciliate was a little higher than that of Anemia, and the optimum temperature for the former was a little lower than that of the later. This should be a reason for that these two species have different ecological nich at the same habitat using the same food source.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.591-596
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• 2012

Stream of Hongchon in Gangwon province was well known site for river otter(Lutra lutra) habitat. Because of habitat importance in this region a food analysis was conducted using 478 spraints of the species. A total food was domintnant by fish species occupying 80.5% and the dominant species was Zacco temminckii because of population abundance. Other food items were Amphibians and birds. Summer food was the highest due to its diversity. Gunup and Naechon streams were not different among diversity. Currently the highway construction was underway and we need more information regarding habitat requirement, and management implication for the species in this region.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.3
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• pp.47-55
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• 2011

Cicada is a very familiar insect to people but habitat characteristics of them are not well known. To investigate habitat characteristics of cicada nymph, plant species, plant cover, soil hardness, accumulated organic mass, organic content in soil, and root density were investigated at 11 sites in an apartment complex garden in Seoul. Selected sites had different densities of cicada nymph case above the ground. Density of cicada nymph case was positively correlated with accumulated organic mass, organic content in soil, and root density and negatively correlated with soil hardness. Even though shrub coverage was not linearly correlated with the density of cicada nymph case, 80% cover of shrub was necessary for the high density of them. Data in this study suggested that organic matter in addition to root density be the primary limitation factor of cicada nymph and high amount of litter-fall decrease soil hardness through the increase of soil organic matter. This study suggests that the density of cicada nymph can be managed through organic content in soil.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.150-158
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• 2006

Over the past few years, many studies have been conducted on the flow, sediment movement, pollution transportation and scour etc. However, very few attempts have been made at the hydraulic studies reflecting upon the ecological function. The objective of this study is to examine the structures of the flow and turbulence in an open circular channel and their relationship to distribution of the organisms and chironomids. Under different flow conditions, the organic matter and some chironomids were injected into the channel. Using the obtained velocity data, the flow mechanisms and the turbulent shear stresses were analyzed. Organic matters and chironomids were distributed on the region that the velocity was slower and the turbulent shear stresses were smaller. Some habitat moved even though chironomids were inhabited. This phenomenon has relationship with the flow mechanism. Some chironomids have distributed around the habitat structure of a hemisphere. The secondary flow has affected the deposition of the organic matters and the distribution of chironomids.

• Journal of Korea Water Resources Association
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• v.38 no.1
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• pp.49-57
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• 2005

The investigation and evaluation of river naturalness was conducted for sample rivers-Hongchungang, Mihochun, Naesungchun - using the method from previous paper 'The Evaluation of River Naturalness for Habitat Restoration : I. Proposal of Evaluation Method'. As a result, Hongchungang and Naesungchun, Mihochun showed 2$^{nd}$ Grades with averaged point 1.92, 1.43, and 2.31. Also comparison and examination of the relationship between water quality and river naturalness shows a little relation with coefficient of correlation 0.575. This result means that the evaluation of river naturalness can be possibly used as index to evaluate river ecology, from a different standpoint with water quality.oint with water quality.