• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.248-253
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• 2005

AfsR2, originally identified from Streptomyces lividans, is a global regulatory protein which stimulates antibiotic biosynthesis. Through its stable chromosomal integration, the high level of gene expression of afsR2 significantly induced antibiotic production as well as the sporulation of S. lividans, implying the presence of yet-uncharacterized AfsR2-target proteins. To identify and evaluate the putative AfsR2-target proteins involved in antibiotic regulation, the proteomics-driven approach was applied to the wild-type S. lividans and the afsR2-integrated actinorhodin overproducing strain. The 20 gel-electrophoresis gave approximately 340 protein spots showing different protein expression patterns between these two S. lividans strains. Further MALDI-TOF analysis revealed several AfsR2-target proteins, including glyceraldehyde-3-phosphate dehydrogenase, putative phosphate transport system regulator, guanosine penta phosphate synthetase/polyribonucleotide nucleotidyltransferase, and superoxide dismutase, which suggests that the AfsR2 should be a pleiotropic regulatory protein which controls differential expressions of various kinds of genes in Streptomyces species.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.459-468
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• 2013

In the application of the ecosystem-based fisheries assessment Jeonnam marine ranching ecosystem, two fisheries, funnel fishery and trap fishery, were selected as target fisheries. Black seabream, Acanthopagru schlegelii, rock bream, Sebastes inermis, gray mullet, Mugil cephalus, were selected as target species for the funnel fishery, and conger eel, Conger myriaster, was target species for the trap fishery. For assessing indicators of four management objectives, that is the maintenance of sustainability, biodiversity, habitat quality and socio-economic benefits, indicators were selected considering the availability of data, which were 5 indicators for sustainability, 3 indicators for biodiversity, 4 indicators for habitat, 2 indicators for socio-economic benefit. The Objective risk indices for sustainability and biodiversity of two fisheries were estimated at yellow zone, medium risk level. The objective risk indices for habitat and socio-economic benefit were estimated at green zone, safe level. The species risk indices (SRI) were estimated at yellow zone. The fishery risk indices (FRIs) were estimated at 1.143 and 1.400 for funnel net fishery and trap fishery, respectively. Finally the ecosystem risk index estimated at 1.184.

• Journal of Environmental Impact Assessment
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• v.20 no.3
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• pp.367-379
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• 2011

This study was conducted to develop an ecological park planning model to enhance the functions of habitats and ecological corridors in Green Belt Areas, because changing policies have resulted in the degredation of the Green Belts due to progressive fragmentation of ecosystems. The principal outcome of the study is to plan an ecological park model through the restoration of habitats. In order to evaluate the capacity of the model to enhance the ecological functions of habitats and ecological corridors in Green Belt Areas, a simulation of habitats was carried out in the Sungnam-Yusoo region. The model was developed via following steps: 1. Selection of candidate sites and selection of the study site by analyzing development factors; 2. Selection of target species that can represent the habitat at the site; 3. Analysis of the site's suitability index for the target species; 4. Establishment of a conceptual plan to enhance and expand the currently produced suitability index; 5. Creation of a master plan based on the conceptual plan; and 6. Evaluation of the enhanced and expanded suitability index of the site. The study showed that the Habitat Unit (HU) of Rana coreana, which was selected as the target species of the study, increased from $28,044m^2$(3.6%) to $224,352m^2$(28.8%), and the HU of the site as the ecological corridor for wild animals increased from $4,674m^2$(0.6%) to $152,684m^2$(19.6%). The study results show that the ecological deficits of the Green Belt Area can be overcome by enhancing the ecological functions of the region, which should be beneficial. The model could be utilized for effective enhancement and management of other Green Belt Areas.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3B
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• pp.311-317
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• 2009

Similarity indices between sampling sites are calculated and cluster analysis of fish community is carried out by UPGMA based on investigating fish fauna and water environment. The restoration indicators as target species of Wonju stream are selected Cottus poecilopus, Zacco temmincki, and Zacco platypus along upper, middle, and lower streams, respectively. For better habitat suitability, low flow increasing and induced water quality improving must be secured by sewer system rearrangement and watershed management. Composite habitat suitability of Zacco temmincki as target species at middle stream of Wonju stream improve significantly by low flow increasing, which is very important factor to improve habitat suitability. The changes of hydraulics of depth and velocity govern the habitat suitability in general, but the effects are not significant. Low flow increasing with the change of 10% reducing of lower channel improves the composite habitat suitability of 0.37~0.78 to their origin of 0.1~0.25, which represent the channel restoration scheme of Wonju stream for enhancing the habitat suitability of fish community.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.4
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• pp.317-325
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• 2022

Korean tuna purse seine fishery in the Western and Central Pacific Ocean (WCPO) began to operate in earnest in the early 1980s. Since then, the total catch has shown an increasing trend and the target species are skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacare) and bigeye tuna (Thunnus obesus). Based on the operational data of Korean tuna purse seine fishery from 2016 to 2020, the catch rates of target species (skipjack and yellowfin tunas) were analyzed by operation time for set types (free school and FAD sets). In the case of the free school sets, they were usually made from sunrise to sunset, and the catch rate was high before and after sunrise for skipjack tuna and before sunset for yellowfin tuna. On the other hand, for the FAD sets, more than 90% of them were made just before sunrise, and there were few operations during the daytime. The purpose of this study is to examine whether there are differences in the catch rate of skipjack and yellowfin tunas by operation time and by school type for Korean tuna purse seine fishery in the WCPO, which could be helpful in understanding its fishing characteristics and providing useful information for developing the stock indices of the target species.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.17-26
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• 2005

Ecological corridor is the facility to connect two habitats fragmented by roads, dam, housing and industrial area. Critics of faunal corridors have suggested that they are simply an untested application of unproved island biogeography theory. But, everyone agree that ecological corridor is important useful structural components that help animal movement in fragmented landscapes. There are 52 ecological corridors in Korea. We investigated 43 ecological corridors of these and recorded the size of corridor, planting species, management and growth condition. We compared planting species to nearby exiting vegetation species and structure. We found that there are no considerations for many aspects of planting, for example, planting species, structure, animal migration and behavior, surrounding vegetation etc. Expecially, It was ignored management of plants, difference of surrounding vegetation, lacks of diverse planting species and structure. We suggest planting the native species of tall tree, shrub and ground cover, edge planting for transitional space between road and natural habitat, planting for foraging and breeding of target animal, diverse layer vegetation, and open space of center for rapid animal dispersal.

• Journal of Environmental Health Sciences
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• v.44 no.6
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• pp.581-590
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• 2018

Objectives: We aimed to investigate the species composition of fish and benthic macroinvertebrates in the Namgang Dam reservoir and assess the reservoir's ecological quality. Methods: Fish and benthic macroinvertebrates were seasonally sampled around the Namgang Dam reservoir from October 2013 to September 2014. Results: A total of 970 fish specimens were collected for this survey, including 4 orders, 14 families, and 25 species. Fourteen endemic species were observed, including Coreoleuciscus splendidus. The most observed among the endemic species caught was Zacco koreanus (14.4%). A total of 9,093 benthic macroinvertebrates, including 51 families and 92 species, were also found. The predominant species in the study area was Chironomidae sp. 1. Diplonychus esakii, whose habitat is distribution-specific as designated by the Korean National Institute of Environmental Research (NIER), were also observed. A total of 386 specimens were collected of the invasive alien species Lepomis macrochirus, and the percentage of Lepomis macrochirus and Micropterus salmoides made up 42.0% of all specimens collected in the area. Conclusion: The mean ecological score of the benthic macroinvertebrate community (ESB) ranged between 24 and 40, which indicates that the environmental condition of the target sites is somewhat poor. Based on the results of this research, building habitats for benthic macroinvertebrates should be considered, and extermination plans for invasive alien fish species should be prepared.

• Journal of Environmental Analysis, Health and Toxicology
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• v.21 no.4
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• pp.304-315
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• 2018

Located in Gimhae, Hwapo is the biggest riverine wetland in the province of Gyeongsangsam-do, Korea, and is a major habitat for various species. However, it is suspected that various pollutants enter the wetlands from agricultural and industrial areas. This study identifies major organic pollutants in this wetland and their sources using high performance liquid chromatography-high resolution mass spectrometry during one summer season. Forty-five substances were selected for quantitative analysis using target screening, and other non-selected compounds were screened using suspect and non-target screening methods. The results were that 21 and 17 targeted substances were detected in July and August, respectively. Major pollutants in July and August were oxadiazon (July: 17-220 ng/L, August: 66-460 ng/L), carbendazim (July: 10-110 ng/L, August: 64-520 ng/L), caffeine (July: 33-1,100 ng/L, August: 56-580 ng/L), and niflumic acid (July: 23-75 ng/L, August: 42-290 ng/L). Sampling sites S4 in July and S2 in August were the major inflow points. Ten substances (tricyclazole, hexaconazole, diuron, fexofenadine, irbesartan, simetryn, cimetidine, valsartan, tebuconazole, and benzotriazole) and four metabolites (valsartan acid, azoxystrobin acid, TEB_M324c, and 2-aminobenzimidazole) were tentatively identified through suspect and non-target screening, respectively.

• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.307-315
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• 2022

In terms of habitat conservation, it is essential to develop a habitat assessment system that can evaluate not only the suitability of the current habitat, but also the health and stability of the habitat. This study aimed to develop a methodology of habitat quality assessment for endangered species by analyzing various existing habitat assessment methods. The habitat quality assessment consisted of selecting targeted species, planning of assessment, selecting targeted sites, assessing performance, calculating grade, and expert verification. Target sites were selected separately from core and potential habitats using a species distribution model or habitat suitability index. Habitat assessment factors were classified into ecological characteristic, landscape characteristic, and species-habitat characteristic. Ecological characteristic consisted of thirteen factors related to health of tree, vegetation, and soil. Landscape characteristic consisted of five factors related to fragment and connectivity of habitat. Species-habitat characteristic consisted of factors for evaluating habitat suitability depending on target species. Since meanings are different depending on characteristics, habitat quality assessment of this study could be used by classifying results for each characteristic according to various assessment purposes, such as designation of alternative habitats, assessment of restoration project, and protected area valuation for endangered species. Forest habitat quality assessment is expected to play an important role in conservation acts of endangered species in the future through continuous supplementation of this system in regard to quantitative assessment criteria and weighting for each factor with an influence.

• Korean Journal of Environmental Biology
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• v.41 no.2
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• pp.109-125
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• 2023

This study was conducted to select target fish species as baseline research for accumulation analysis of major hazardous chemicals entering the aquatic ecosystem in Korea and to analyze the impact on fish community. The test bed was selected from a sewage treatment plant, which could directly confirm the impact of the inflow of harmful chemicals, and the Geum River estuary where harmful chemicals introduced into the water system were concentrated. A multivariable metric model was developed to select target candidate fish species for hazardous chemical analysis. Details consisted of seven metrics: (1) commercially useful metric, (2) top-carnivorous species metric, (3) pollution fish indicator metric, (4) tolerance fish metric, (5) common abundant metric, (6) sampling availability (collectability) metric, and (7) widely distributed fish metric. Based on seven metric models for candidate fish species, eight species were selected as target candidates. The co-occurring dominant fish with target candidates was tolerant (50%), indicating that the highest abundance of tolerant species could be used as a water pollution indicator. A multi-metric fish-based model analysis for aquatic ecosystem health evaluation showed that the ecosystem health was diagnosed as "bad conditions". Physicochemical water quality variables also influenced fish feeding and tolerance guild in the testbed. Eight water quality parameters appeared high at the T1 site, indicating a large impact of discharging water from the sewage treatment plant. T2 site showed massive algal bloom, with chlorophyll concentration about 15 times higher compared to the reference site.