• Journal of Environmental Health Sciences
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• v.13 no.1
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• pp.1-5
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• 1987

The study on shellfish fauna around eleven artificial lakes was carried out from April to September in 1986. The identified shellfishes in total surveyed area are composed of 13 species, 6 families, 4 orders, 2 classes and among them, the dominant species was Semisulcospira forticosta. Corbicula japonica which had been inhabited in Paltangho was collected in Chunchonho and Uiamho in this study. Consequently, the distributional area was gone up north. Especially, Radix auricularia, Parafossarulus manchuricus and Austropeplea ollula were collected in Paltangho and Uiamho are indicators of $\alpha$-mesosaprobe. Therefore it is necessary the countermearsure on management of water quality for the security of the source of water supply.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.93-99
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• 2022

It was confirmed that the fish diversity decreased with increasing index of weir's density (IWD) in the four river systems. The IWD showed difference with watershed, it was high in the Nakdong River (NDR). Both two river systems of Gum River (GUR) and Yeongsan River (YSR) were similar, whereas relatively lower density observed in the Han River (HNR) system. A result of 2-Dimensional Kolmogorov-Smirnov (2-DKS) as a nonparametic test showed different threshold values affecting fish diversity with the river systems. The p-values based on D_max, were significantly different at 0.05 level (except for YSR). The threshold values affecting fish diversity were also different with watershed. The values were 1.6/km of the HNR, 1.3/km of the NDR, and 2.3/km of the GUR, respectively. The fish diversity was decreased when IWD is over threshold values. The IWD of total 404 rivers (about 33%) among 1,217 surveyed in this study showed above threshold value. These rivers should be considered first for evaluating river continuity. The IWD and threshold value suggested in this study would be useful for selecting a stream priority for river connectivity study.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.100-106
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• 2022

The relationships between river length and weir density versus fish species observed were analyzed for 210 local rivers in the Seomjin River system (SJR). A nonlinear exponential relationship between river length and number of fish species were observed. Model coefficient was 0.03 and coefficient of determinant (R²) was 0.59, meaning that about 59.0% of total variance was explained by river length variable. Predicted value by model and observed number of species showed a difference. About 110 local rivers (about 52.4%) showed lower value than predictive value. The average index of weir's density (IWD) in the SJR was about 2.7/km, which was significantly higher than that of other river basins. As a result of nonparametric 2-Kimensional Kolmogorov-Smirnov (2-DKS) analysis based on the IWD, the threshold value affecting fish diversity was about 2.5/km (D_max=0.048, p<0.05). Above the threshold value, it means that the number of fish species would be decreased. In fact, the ratio of the expected species to the observed species was lowered to less than 70%, when the IWD is higher than the threshold value. To maintain aquatic ecological connectivity in future, it is necessary to manage IWD below the threshold value.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.1
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• pp.53-61
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• 2021

Distribution of fish community depends largely on environmental disturbance such as habitat change. In this study, we evaluated the impact of environmental variables and microhabitat patch types on fish distribution in Yudeung Stream at 15 sites between early May and late June 2019. We used non-metric multidimensional scaling to examine the distribution patterns of fish in each site. Gnathopogon strigatus, Squalidus gracilis majimae, Zacco koreanus, and Zacco platypus were associated with riffle and boulder areas, whereas Iksookimia koreensis, Acheilognathus koreensis, Coreoleuciscus splendidus, Sarcocheilichthys nigripinnis morii, and Odontobutis interrupta were associated with large shallow areas. In contrast, Cyprinus carpio, Carassius auratus, Lepomis macrochirus, and Micropterus salmoides were found at downstream sites associated with large pool areas, sandy/clay-bottomed areas, and vegetated areas. On the basis of these results, we suggest that microhabitat patch types are important in determining the diversity and abundance of fish communities, since a mosaic of different microhabitats supports diverse fish species. As such, microhabitat patches are key components of freshwater stream ecosystem heterogeneity, and a suitable patch composition in stream construction or restoration schemes will support ecologically healthy food webs.

• Journal of Industrial Convergence
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• v.2 no.1
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• pp.73-89
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• 2004

This study uses theoretical perspectives and models from organizational ecology to examine the dynamics and viability of strategic groups. Integrating the ecological perspective and the contingency theoretical view of strategic management, this study developed propositions demonstrating the impact of environmental density and variation on the effectiveness of strategic groups. Justifications for linking ecological perspectives to strategic management theory are discussed and the importance of the integrative approach to strategic management is highlighted.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.274-274
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• 2019

• Journal of Environmental Impact Assessment
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• v.2 no.2
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• pp.85-93
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• 1993

Aims of the EXCEPT project and tasks and characteristics of the EXCEPT system are presented based on an analysis of urban planning EIAs. The methodology of evaluation in EIAs, which had to be developed in order to program the system, is based on a model of evaluation processes. Evaluation principles, evaluation rates, an environmental model and a model of the projects being planned are presented. The evaluation concern re-unifies the different components of evaluation again.

• Carbon letters
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• v.16 no.4
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• pp.265-269
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• 2015

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2007.10a
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• pp.74-77
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• 2007

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.124.1-124
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• 2001

No Abstract, See Full Text