• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.185-191
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• 2012

Most of Korean farms have been developed in the semi-closed bay, and its position is very vulnerable to the coastal contamination due to the long term and the high density. So, mariculture management is very essential for the sustainable aquaculture. Some of the specific ways would be the assessment of the optimal stocking density for mariculture management zone and this has to consider both the suitable site selection and the assessment of ecological carrying capacity. Habitat suitability index(0.0 totally unsuitable habitat, 1.0 optimum habitat) and ecological indicator(Filtration pressure indicator) was used to assess the stocking density for oyster farms in Geoje-Hansan Bay. Geoje Bay showed the higher habitat suitability index value 0.75 than Hansan Bay 0.53, indicating that Geoje Bay is more suitable for oyster farming. Ecological indicator showed different stocking density according to the coastal characteristics in Geoje-Hansan Bay. Consequently, it is desirable that the stocking density in Geoje Bay should reduce average 40% and Hansan Bay, average 60% than present, in order to meet the ecological carrying capacity. The assessment of the stocking density could solve various problems such as the coastal contamination, environmental aggravation and the productivity decrease and this study could be a scientific basis to establish the policies for mariculture management.

• Journal of Wetlands Research
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• v.24 no.4
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• pp.213-223
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• 2022

This study was conducted to establish a Habitat Suitability index (HSI) based on literature research and field surveys on ecology and habitat of 'Hynobius leechii'. And this study will be used as basic data for qualitative evaluation of habitat environment. The survey sites were divided into natural habitats close to the prototype habitat and artificial restoration areas where Hynobius leechii was monitored. So the types of habitats were diversified. Hynobius leechii is a vulnerable species to climate change because it is affected by the microhabitat and has low mobility. HSI variables of Hynobius leechii were extracted through domestic and overseas literature, and standards were extracted from literature research and field survey. The standards were presented as a value of the physical allowable category in consideration of realization. To verify the study, an in-depth consultation was conducted by amphibians experts. HSI variables of Hynobius leechii were included 9 variables such as Overstory canopy cover(%), Understory cover(%), Water-pH, Soil-pH, Soil relative humidity(%), Leaf litter depth(cm), Rock substrates (%), Type of Coarse woody, Distance from Street or Pollutant(m).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.5
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• pp.39-47
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• 2013

The agricultural area is a priority to develop than the natural area for land developments. However, the importance of agricultural biodiversity is emphasized recently. The agricultural area does not only provide food for human and habitat for wild life but also contribute to improve biodiversity. It is necessary to preserve the agricultural area with rich biodiversity. The study was conducted to analyze biodiversity of insects for conservation value assessment of agricultural areas. According to the results of field survey, there is higher biodiversity index in agricultural areas surrounding the forest or small size agricultural areas. By contrast, the index is lower in agricultural areas near roads or in the intensive agricultural area. The results show that there is high biodiversity in agricultural areas, especially margin agricultural area such as below 2ha and over slop rate of 15%. Therefore, further studies should be conducted field survey more to generalize for biodiversity in agricultural area, and establish the criteria to protect agricultural area from land developments.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.154-163
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• 2021

This study was carried out to present the habitat distribution status and the habitat distribution prediction of Sophora koreensis, which is the Korean Endemic Plant included in the EN (Endangered) class of the IUCN Red List. The habit distribution survey of Sophora koreensis confirmed 19 habitats in Gangwon Province, including 13 habitats in Yanggu-gun, 3 habitats in Inje-gun, 2 habitats in Chuncheon-si, and 1 habitat in Hongcheon-gun. The northernmost habitat of Sophora koreensis in Korea was in Imdang-ri, Yanggu-gun; the easternmost habitat in Hangye-ri, Inje-gun; the westernmost habitat in Jinae-ri, Chuncheon-si; and the southernmost habitat in Sungdong-ri, Hongcheon-gun. The altitude of the Sophora koreensis habitats ranged from 169 to 711 m, with an average altitude of 375m. The area of the habitats was 8,000-734,000 m², with an average area of 202,789 m². Most habitats were the managed forests, such as thinning and pruning forests. The MaxEnt program analysis for the potential habitat of Sophora koreensis showed the AUC value of 0.9762. The predictive habitat distribution was Yanggu-gun, Inje-gun, Hwacheon-gun, and Chuncheon-si in Gangwon Province. The variables that influence the prediction of the habitat distribution were the annual precipitation, soil carbon content, and maximum monthly temperature. This study confirmed that habitats of Sophora koreensis were mostly found in the ridge area with rich light intensity. They can be used as basic data for the designation of protected areas of Sophora koreensis habitat.

• Journal of Environmental Science International
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• v.16 no.8
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• pp.973-983
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• 2007

The eco-hydrologic effects of maintenance water supply on Oncheon stream are studied using hydrologic, hydraulic and ecologic models. SWMM (Storm Water Management Model) is used for long-term simulation of runoff quantity and water quality from Oncheon stream watershed. Using the output hydrologic variables from SWMM, HEC-RAS (River Analysis System) is then used to simulate the hydraulics of water flow through Oncheon stream channels. Such hydrologic, hydraulic and water quality output variables from SWMM and HEC-RAS are served as input data to execute PHABSIM (Physical Habitat Simulation) for the purpose of predicting the micro-habitat conditions in rivers as a function of stream flow and the relative suitability of those conditions to aquatic life. It is observed from the PHABSIM results that the weighted usable area for target fishes has the maximum value at $2m^3/s$ of instream flow. However, mid and down stream areas that have concrete river bed and covered region are unsuitable for fish habitat regardless of instream flow increment. The simulation results indicate that the simple maintenance water supply is limited in its effect to improve the ecological environment in Oncheon stream. Therefore, it is imperative to improve water quality and to recover habitat conditions simultaneously.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.4
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• pp.24-36
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• 2008

The essence of a natural stream restoration project is providing habitats for various creatures in terms of the stream's environmental function. This research suggests the problems of natural stream restoration project by studying streams in terms of habitats for creatures and reviewing the national and international cases on existing natural stream restoration project. As a solution for the above, this research suggests a preservation method for biotope of upper stream areas focusing on the fish biotope area considering the ecological characteristics and preservation value of the respective stream so that the stream can be preserved as habitats for creatures. The research was carried out on Cheonglimli Baekcheon region which is an upper stream area of Buan-Dam located in the public park in Byunsanbando, Buangoon, Jeonlabookdo. We suggest the preservation method based on the habitat environment and keystone species of fish. The habitat environment evaluation was carried out mainly being divided into three groups namely, habitats and surrounding environment, reservoir's features and fish way and the diversity of fish. By improving the problematic elements discovered through such evaluation, it tries to improve the biotope of the stream and continuously preserve the stream. In addition, in order to restore the stream as habitats for various creatures, this research suggests to select keystone species which are suitable for the stream environment and restore the habitats based on the keystone species rather than restoring habitats for all species. Fish not only plays the role of a consumer of Epilithic algae and water beetles but also plays an important ecological role as a food for birds or small mammalia. If such ecologically important biotope for fish is preserved, the ecological environment of the stream will be maintained more stably.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.527-536
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• 2007

In this study, we applied 10-metric health assessment model, based on the Index of Biological Integrity (IBI) during 2006 in the Changwon Stream, which is located in the Changwon city, Gyeongnam province, S. Korea, and then compared with water quality data. The Index of Biological Integrity (IBI) in the Changwon Stream varied from 18 to 38 in the watershed depending on the sampling location and averaged 30.3 (n=6) during the study. Analysis of tolerance guilds showed that the proportion of sensitive species was 13%, but tolerant and intermediate species were 34% and 53%, respectively. Qualitative Habitat Evaluation Index (QHEI) averaged 43.3 (range: 65-104, n=6) indicating non-supporting condition, based on the criteria of U.S. EPA (1993). Values of QHEI showed a typical longitudinal decreases from the headwater reach to the downstream location, except for Site 1 with a low QHEI value by artificial habitat by concrete construction. Minimum QHEI was found in Site 4 where fish diversity was minimal. Conductivity increased continuously along the gradients and especially showed abrupt increases in the downstream sites along with turbidity. Stream ecosystem health of IBI matched to the values of QHEI except for S6. Low IBI values in the sites 4 and 5 was considered to be a result of combined effects of chemical pollutions and habitat degradations. Our results support the hypotheses of Plafkin et ai. (1989) that physical habitat quality directly influences the trophic structure and species richness, and is closely associated with IBI values.

• Journal of Life Science
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• v.22 no.11
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• pp.1435-1443
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• 2012

The changes of plant communities at Angol valley and Baetgol valley in Geoje-do were studied. Both ${\alpha}$-diversity and ${\gamma}$-diversity decreased with the sizes and degrees of habitat fragmentations. The mean number of winner species decreased with habitat fragmentation. All Quercus species, including Quercus acutissima, significantly declined in importance, while the many introduced species, including Trifolium pretense, all increased in importance. As the proportional change in adult survival rate increased, the absolute value of the bias in the elasticity prediction also increased from 2003 to 2011 at undisturbed forests. However, the bias was low for decreases in disturbed populations. Moran's I values showed overall decreases for habitat fragmentation and for the periods of habitat conversion. Eventually, plant communities, due to urbanization in Goeje-do, might have led to decreased chances of common species when the environment was disturbed.

• Journal of Korean Society on Water Environment
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• v.24 no.3
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• pp.317-327
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• 2008

This study developed the methodology to calculate the total daily maximum load (TMDL) using the instreamflow requirement because the previous TMDLs were too simple to easily achieve. Instreamflow requirement which was the average low flow ($Q_{275}$) in the previous planning cannot consider the seasonal variation of streamflow. Therefore, this study used the instreamflow requirement which is a maximum value among hydrologic drought flow ($Q_{355}$), and environmental flows for ecology and scenery. The environmental flows for ecology were calculated using Physical HABitat SIMulation system (PHABSIM) which can estimate the necessary flow for fish survival by life cycle. Using the proposed method, all monthly TMDLs of streams in the Anyangcheon were calculated for the application.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.570-578
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• 2007

In order to investigate the basic vegetation information for the efficient management of the Sorbus commixta habitat in Korea, 31 plots in Mt. Chiri area were selected of which vegetation types were classified in phytosociological method and ecological characteristics were identified. As a result, the habitat was classified as S. commixta community group which was then subdivided to Prunus padus group and Picea jezoensis group. Prunus padus group was classified in Ainsliaea acerifolia subgroup and Magnolia sieboldii subgroup, while the Picea jezoensis group was classified in Rhododendron mucronulatum subgroup and Echinopanax horridum subgroup. Thus, the forest vegetation of S. commixta was classified in 1 community, 2 groups and 4 subgroups, and found to have 4 vegetation units in total.