• Korean Journal of Ecology and Environment
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• v.43 no.4
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• pp.503-512
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• 2010

This study was conducted to evaluate fish fauna, species composition, and various guilds against stream orders along with analysis of fish community structure and diversity in Geum River watershed from 2005 to 2007. The total number of fish collected was 4,216 representing 12 families with 56 species. Zacco platypus was the most abundant fish species with 26% in relative abundance (RA). Korean endemic species were 24 species including Zacco koreanus, Microphysogobio yaluensis, Gobiobotia nakdongensis, and Iksookimia koreensis, etc. We also collected endangered fish species such as G. nakdongensis, Liobagrus obesus, and Pseudopungtungia nigra, etc., and their new distribution sites were found in the survey, providing some sites of the fish conservation and protection. Fish tolerance and trophic guilds analysis showed that the proportion of sensitive species, intermediate species, and tolerant species were 33.4%, 29.3%, and 37.3%, respectively and omnivores and insectivores were 48.1 % and 38.4%, respectively. Analysis of site-base study indicated that tolerant species and omnivore species were high in some polluted tributary streams (i.e., Gap and Miho stream) and sensitive and insectivore species were low. In the functional relations, expressed as simple linear regression equations, of stream order on fish metric attributes, showed that the number of species and the number of individuals increased as the stream order increases. This phenomenon was explained by greater availability of stable water volume, rich food, and higher physical habitat capacity. Such guild compositions and stream order characteristics of the river influenced the community structures, based on species diversity, dominance and evenness index in the study. This study may be used as important data in the future for comparisons of fish fauna and compositions before and after two weir (dam) constructions in the middle of Geum River by the government.

• International Journal of High-Rise Buildings
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• v.7 no.2
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• pp.145-151
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• 2018

Newly-designed high-rise buildings, both in China and abroad, have demonstrated new innovations from the creative concept to the creative method. from the creative concept to the creative method. At the same time, digital technology has enabled more design freedom in the vertical dimension. "Twisting" has gradually become the morphological choice of many city landmark buildings in recent years. The form seems more likely to be driven by the interaction of aesthetics and structural engineering. Environmental performance is often a secondary consideration; it is typically not simulated until the evaluation phase. Based on the research results of "DigitalFUTURE Shanghai 2017 Workshop - Wind Tunnel Visualization", an approach that can be employed by architects to design environmental-performance buildings during the early stages has been explored. The integration of a dynamic form-finding approach (DFFA) and programming transforms the complex relationship between architecture and environment into a dialogue of computer language and dynamic models. It allows the design to focus on the relationship between morphology and the surrounding environment, and is not limited to the envelope form itself. This new concept of DFFA in this research consists of three elements: 1) architectural form; 2) integration of wind tunnel and dynamic models; and 3) environmental response. The concept of wind tunnel testing integrated with a dynamic model fundamentally abandons the functional definition of the traditional static environment simulation analysis. Instead it is driven by integral environmental performance as the basic starting point of morphological generation.

• Journal of agriculture & life science
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• v.53 no.2
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• pp.65-75
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• 2019

Stem and root of elm trees have used as traditional medical materials, but there is little information on the distribution and resources of habitats. Korean native growing Ulmus spp. (U. davidiana var. Japonica, U. parvifolia, U. davidiana, and U. macrocarpa) genetic resources studied through The National Forest Inventory of Korea data and field survey. The distributions of U. davidiana var. japonica according to elevation distributed evenly. Both U. parvifolia and U. davidiana were inhabited mostly at less than 200 m of altitude. Each Ulmaceae species widely were distributed nationwide, but a dominant species was different depending on locals. It observed that Ulmaceae inhabits mainly in steep slopes of 31-45 degrees. Most of the habitats regenerated by natural seeding and the most abundant species were a codominant tree. Distribution of trees in U davidiana var. japonica was 7 m-13 m, and in young U. parvifolia and U. macrocarpa, more than 25% of young trees less than 7 m observed. The distribution of the diameter of breast height of the U. davidiana var. japonica was 46.4% for 11-20 cm, 52.6% for 11-20 cm in U. parvifolia. The average T/R ratio was 0.83, and the mean weight ratio of root bark was 62%. As the results of this study, the domestic Ulmaceae biomassare very small. It is difficult to harvest in that the habitat on the slope. Thus, it is too hard to develop functional materials using biomass at present. Therefore, it is necessary to develop technology for the selection and propagation of elite trees of Ulmaceae.

• Journal of Korean Society on Water Environment
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• v.37 no.3
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• pp.190-203
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• 2021

Water quality, benthic macroinvertebrate communities, and other factors were investigated to explore the effects of the effluent discharge from a sewage treatment plant into Jwagwang stream in Busan in 2019. During the study period, the flow rate of this stream was in the range of 10,400 m³/day to 52,200 m³/day except for the discharge of about 24,000 m³/day of the effluent. After discharge, the flow velocity increased by about 65% and the water depth increased by about 40%. At sites downstream of the discharge point, BOD, COD, TOC, T-N, T-P, and other water quality values were worse than those of the upstream sites. The periphytic algal chlorophyll-a concentrations in the natural substrata were higher than those of the upstream sites, especially in May and August. However, at sites downstream of the discharge point, the individual numbers of Annelida were decreased and individual numbers of the insecta of arthropoda were increased. Also, species numbers and the diversity and dominance indexes were improved in the sites downstream of the discharge point. The functional feeding groups (FFGs) of collector-filterers were increased and the habitat orientation groups (HOGs) of sprawlers, burrowers, and clingers were especially increased at the sites with additional reclaimed wastewater effluent flow. Regardless of the effluent discharge, BMI, an indicator of ecological stream health using benthic macroinvertebrate species, did not show large gaps between the study points. Although the water quality of the sites downstream of the discharge point was much worse than those upstream, their ecosystem soundness was better than those of the upstream sites from an ecological perspective.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.194-207
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• 2021

It is necessary to assess and manage the different elements of the marine ecosystem, such as climate change, habitat, primary and secondary production, energy flow, food web, potential yield, and fishing, to maintain the health of the ecosystem as well as support sustainable development of fishery. We set up an ecosystem model around the Korean peninsula to produce scientific predictions necessary for the assessment and management of marine ecosystems and presented the usability of the model with scenario experiments. We used the Atlantis ecosystem model based on the marine food web; Atlantis is a three-dimensional end-to-end model that includes the information and processes within an entire system, from an abiotic environment to human activity. We input the ecological and biological parameters, such as growth, mortality, spawning, recruitment, and migration, to the Atlantis model via functional groups using existing research and local measurements. During the simulation period (2018-2019), we confirmed that the model reproduced the observed data reasonably and reflected the actual ecosystem characteristics appropriately. We thus identified the usability of a marine ecosystem model with experiments on different environmental change scenarios.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.148-156
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• 2022

Ecological occupation in irrigation ponds is a well-acknowledged fact that is essential for biodiversity conservation in agricultural ecosystems. However, there are few studies on the ecological functions and relationship between a paddy field and irrigation using macroinvertebrates in an environmentally friendly paddy field. The objective of this study is to identify the community and distribution characteristics of macroinvertebrates in an agricultural paddy field and irrigation pond ecosystems, and to provide basic data on the ecological function of an environmentally friendly paddy field. Macroinvertebrate sampling was conducted from May to September in an agricultural paddy field and irrigation pond in an environment-friendly paddy field in Boryeong city. We conducted a study to identify the distribution characteristics using macroinvertebrate species analysis, such as Functional Feeding Groups (FFGs), Habitat Oriented Groups (HOGs), rarefaction curve, and a two-way dendrogram. A total of 37 species of macroinvertebrates in 28 families, 13 orders were collected study during the period of the investigation. Dominant taxa of macroinvertebrates included Coleoptera, Hemiptera, and Odonata. In terms of FFGs, predators and gathering collectors accounted for approximately 70%, in relation to HOGs, and climbers and swimmers occupied more than 50% from both the paddy field and irrigation pond. With respect to the rarefaction curve, the irrigation pond (July) was high as E (S, 141)=18 species, while the paddy field (May) was comparatively low as E (S, 141)=9 species. In conclusion, our results revealed that macroinvertebrates, such as Notonecta triguttata, Peltodytes intermedius, Appasus major, Laccotrephes japonensis, Appasus japonicus, Sigara substriata, Enochrus simulans, and Sternolophus rufipes, were used as a habitat and spawning ground in both paddy field and irrigation pond. The irrigation pond appears to be a very important spawning ground for macroinvertebrates.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.190-198
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• 2010

This study was conducted to examine the effects of dams on benthic macroinvertebrate communities in Korean streams and rivers. Four low-head dams and three large dams were studied throughout South Korea. Sampling was taken at immediately upper (impoundment), lower (riffle area), and control (riffle area) sites from the dams during 2004-2007. The upper sites, of which substrate heterogeneity and velocity were relatively low, showed a lower degree of species richness, density, and diversity indices, which is very different from the lower and control sites. Heavily polluted streams showed a lesser degree of community differences between the upper and lower sites. In the large dams, the upper and lower sites showed very low values of species diversity indices and very high values of dominance indices compared to the control sites. In the low-head dams, however, the difference of degree of the values was relatively smaller. Compositions of the functional feeding groups and the habitat orientation groups were relatively simpler at the upper sites than at the lower sites and the degree of difference was greater in the large dams. Species richness and community indices of benthic macroinvertebrates were more significantly affected by habitat characteristics than water quality at the upper sites; however, those were more significantly related with water quality at the lower sites. In conclusion, large and low-head dams could simplify stream habitats particularly at the upper sites (impoundment), and they negatively affected on the benthic macroinvertebrate communities inhabited the habitats. The impact was larger in the large dams than in the low-head dams.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.353-361
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• 2011

This study was conducted to examine the effects of sedimentation caused by highland agriculture on benthic macroinvertbrate assemblages in upper Song Stream from 2006 to 2009. The mean concentrations of water quality parameters (pH, DO, EC, TDS, TN, and TP) were gradually increasing toward downstream but ORP was decreased. Furthermore, biological habitats at lower reaches were more homogeneous and unstable due to sand deposition than those at upper sites. A total 106 species of benthic macroinvertbrates in 47 families, 11 orders, 6 classes, and 5 phyla were identified during whole field surveys. Song Stream showed great declines of overall biological attributes along its longitudinal gradients, particularly in taxa richness and abundance. Of all functional groups scrapers and clingers were most affected against the degradation of habitat quality, whereas collector-gatherers and burrowers showed the opposite case. It was found that such results had close correlations with water quality parameters and substrate composition which played an important role in structuring macroinvertebrate communities. In conclusion, this study represents that disturbance caused by highland agricultural activities had negative effects on benthic macroinvertebrate communities by leading to sand deposition at adjacent stream ecosystems.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.10-18
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• 2014

The habitat characteristic of the Gammarus sobaegensis which is one of the Amphipoda kinds has been found inhabiting in the inter mountain stream at Ganseong stream. From the investigation, the main inhabitant area of the G. sobaegensis maintained the water temperature under $10^{\circ}C$ during the spring and autumn season, and the electric conductivity was also maintaining under $40{\mu}Scm^{-1}$. For the precipitation, for this year when the monthly accredited rainfall did not exceed 800 mm, it did not affect maintaining the population of the G. sobaegensis but when the monthly accredited rainfall exceeded 1,000 mm it was found to be working as a unfavorable condition for maintaining the population. The effect especially from this kind of rainfall created the flow of G. sobaegensis as well as the flow of the fallen leaves which are the food resources and affected the population of the G. sobaegensis as a multiple interruption reason. Among the Functional Feeding Groups (FFGs) distribution depending on the use of the food resources the shredders showed up in the ratio of 20% in the site 1~3, and showed a big difference with the site 4~7 as it showed up in the ratio near 10%. Also, after comparing the variation of the individual number among the G. sobaegensis and shredders at the site 1~3 where G. sobaegensis mainly shows up, it showed the same variation pattern except for 2009.

• Korean Journal of Environment and Ecology
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• v.32 no.4
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• pp.381-391
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• 2018

The purpose of this study is to investigate the influence of artificial disturbances occurring during water conveyance frequency on benthic macro-invertebrate by comparing and analyzing data before and after the construction of Boryeong dam in Boryeong-si, Chungcheongnam-do. We conducted the survey eight times in four points from April 2016 to September 2017. A total of 13,447 individuals from 125 species, 70 families, 19 orders, 7 classes, and 4 phyla were collected. The result of the community analysis showed that the dominant index was 0.55 (${\pm}0.07$) to 0.47 (${\pm}0.08$), diversity index was 2.06 (${\pm}0.26$) to 2.23 (${\pm}0.28$), evenness index was 0.69 (${\pm}0.05$) to 0.70 (${\pm}0.04$), and richness index was 3.43 (${\pm}0.72$) to 4.03 (${\pm}0.91$). After conveyance, the dominance decreased while the diversity, evenness, and richness increased. The result of the functional group analysis showed the portion of scrapers, filtering-collectors increased while that of shredders, gathering-collectors decreased in the functional feeding group and that the proportion of climbers and clingers increased while that of burrowers and sprawlers decreased in the habitat orientation group. The result of analysis of community stability showed that St. 1 and St. 2 decreased resistance and resilience after conveyance and new species appeared in the III characteristics group while St. 3 and St. 4 did not show much difference. The result of multidimensional scaling analysis showed that the variation of similarity was the highest at St. 1 after conveyance, and the variation of similarity at St. 4 was the lowest.