• Asian Journal of Turfgrass Science
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• v.24 no.1
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• pp.50-55
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• 2010

Five turfgrass species and 46 cultivars were investigated for difference of spring greenup and living ground cover. Turf color and Normalized Difference Vegetation Index (NDVI) for greenup were investigated between species and cultivars. Turf color and NDVI were showed significantly different among species and cultivars. Turf color was showed significantly different among 20 cultivars of kentucky bluegrass (Poa pratensis L.). NDVI was significantly difference among 20 cultivars of kentucky bluegrass and 6 cultivars of tall fescue (Festuca arundinacea Schreb). The percentage living ground cover was showed significantly different among creeping bentgrass (Agrostis palustris Huds) cultivars and fineleaf fescue cultivars in spring.

• Journal of Korean Society on Water Environment
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• v.35 no.2
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• pp.152-164
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• 2019

In this study, a Benthic Macroinvertebrates Family Index (BMFI) was developed using 100 indicator groups (99 families including Chironomidae with 2 phena). Families were assigned a score between 1 and 10 depending on their sensitivity to organic pollution. The BMFI was composed of the sensitivity and relative abundance of the indicator taxa. Sensitivity values of each group were generally similar to Biological Monitoring Working Party (BMWP) scores or Walley, Hawkes, Paisley, Trigg (WHPT) scores of UK, Japanese BMWP scores, and the FBI tolerance values of North America. However, sensitivity values of some taxa were significantly different from those of foreign countries, which seemed to have resulted from discrepancy in species composition, difference of taxonomic classification system, or methodological difference for estimation of sensitivity. As an annual average level, BMFI showed significant correlation with concentration of 5-day biochemical oxygen demand (BOD5) (correlation coefficient r = -0.80, n = 569 sites), total suspended solids (r = -0.68), and total phosphorus (r = -0.79). In addition, BMFI revealed strong correlation with Shannon-Weaver's species diversity (r = 0.85), Margalef's species richness (r = 0.85) and McNaughton's dominance (r = -0.84). Correlation between BMFI and water quality parameters or community indices such as species diversity did not show significant difference compared to that of species-level indices such as BMI (Benthic Macroinvertebrates Index). This means that BMFI is a more useful indicator in terms of easy identification of organisms. BMFI was used to assess the environmental status of 3,017 sites of Stream Ecosystem Survey conducted by the Korean Ministry of Environment between 2016 and 2018. As a result, about half of all sites appeared to be in good condition, and a quarter in poor condition.

• Ocean and Polar Research
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• v.28 no.2
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• pp.67-78
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• 2006

Six surface sediments from two offshore transects of Ulsan and Gampo, on the southeastern margin of Korea were taken for sediment and foraminiferal analyses. Sedimentary processes are dominated by reworking and resedimentation from storms in the area off Ulsan and hemipelagic suspension settling in the area off Gampo. Eighty-four foraminiferal species were identified in total assemblages, including 33species of living populations and 9 species of planktonic foraminifera. The characteristics of foraminifera showed differences of offshore environments between Ulsan and Gampo. The number of living species, species diversity and equitability in Gampo offshore area had higher values than those in Ulsan offshore area. However, planktonic/benthic(P/B) ratio showed higher in the Ulsan offshore area. The species diversity indices and P/B ratio indicated that environmental stability and surface-ocean productivity in the Gampo offshore area were relatively higher than the Ulsan offshore area. The difference of species compositions is useful for interpreting the paleoenvironments in mud deposits of the southeastern margin of Korea.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.24-31
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• 1998

This study was performed to investigate the difference in species of test fish on the determination of short-term bioconcentration factor in zebrafish(Brachydanio rerio), red sword tail(Xiphophorus hellieri) and goldfish(Carassius auratus). Experimental concentrations of carbamates were 0.05 and 0.10 ppm and chlorothalonil were 0.005 and 0.01 ppm for 3 and 5 days, respectively. This paper reports the measured BCF value on pesticides in various species of test fish, under steady state, and examined correlation between the BCF value and depuration rate constant or LC$_{50}$ or lipid content. Carbamates and chlorothalonil concentration in fish extract and BCF of carbamate and chlorothalonil were increased as incresing test concentration. Carbamates concentration in fish extract and BCF of carbamate were decreased as incresing test period, but chlorothalonil concentration in fish extract and BCF of chlorothalonil were increased as prolonging test period. Determined pesticide concentration in fish extract and BCF were highest in red sword tail, and followed by goldfish, and zebrafish. Determined depuration rate constant were highest in zebrafish, and followed by goldfish, and red sword tail. 96hr-LC$_{50}$ were highest in red sword tail, and followed by zebrafish, and goldfish. Lipid compositions were highest in red sword tail, and followed by goldfish, and zebrafish. Therefore, it is suggested that the difference of BCF between each pesticide due to those of lipid composition of fish and deputation rate constant, while LC$_{50}$ have no effect on BCF.

• Journal of Species Research
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• v.10 no.1
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• pp.78-85
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• 2021

Heterorhabdus papilliger (Claus, 1863) is newly reported from the Tsushima Warm Current realm of the southern Korean waters. Its morphological diagnostic characteristics generally agreed well with the original description and the previous records of H. papilliger. The female of H. papilliger can be recognized by the genital somite, which in lateral view has a more or less rounded genital prominence and an uninflated posterior ventral margin; the second exopodal segment of male right leg 5 with the medial projection with a large, rounded, plumose proximal lobe, and a poorly developed distal lobe. The genetic difference for the partial mtCOI gene between Korean specimens and H. papilliger from Spain and Japan of the same clade is 0.4%, while the difference between Korean specimens is 0.5%. However, the interspecific difference for the mtCOI gene between H. papilliger from the Korean waters and the other Heterorhabdus species is in the range of 14.7-20.8%, suggesting that the former is a valid species.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.495-502
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• 2007

Species biotic index (SBI), based on a fish assemblage, was applied to a stream assessment using long-term ecological fish data set (1996 to 2001) in Boryong dam area, which is located in the mainstream of Ungchun Stream of Chungnam province, Korea. According to the methods of Hilsenhoff (1988), the scores of tolerance guild assigned 10 classes to each species by its habitat and feeding guild, but modified current 7 criteria to 5 scoring standards due to unclear borderline among species. Relative abundance in the species number of upper stream guilds was only 7% of the total, whereas the abundance in the species number of middle to downstream upper stream guilds was 64%. Mean SBI, based on dataset in Site 1 during 1995-2001 averaged 5.10, which was judged as a "good" condition by the rank criteria of SBI. Before the dam construction, mean SBI in the Site 1 was 4.61, indicating a "good" condition, but after the dam construction, mean SBI was 5.60, indicating a "fair" condition. Trajectory analysis in the Site 1 showed significantly (One-way ANOVA, $F_{6,21}=3.26$, p=0.02) different among years, reflecting the changes of fish composition and population density by the dam construction, whereas Site 2 showed no significant changes ($F_{6,21}=1.00$, P =0.45) difference among years. Mean SBI prior to the dam construction in the Site 3 was 4.52 but after the construction, the value was 6.30, indicating a distinct difference between the pre- and post-dam construction. Trajectory analysis at the Site 3 supported this fact: Values of SBI showed significantly ($F_{6,21}$=14.37, p<0.01) different. Mean SBI was 4.67 in the Site 4, indicating a "good" condition in the health and the health rank was same as the sampling sites 1, 2, and 4. Trajectory in the Site 4 showed no significant ($F_{6,21}=2.35$, p=0.07) difference among the years. Overall, our trajectory analysis indicated that three of four sampling sites (sites 1, 3, 4) showed significant decreases (n=7, p<0.05) and that the proportions of sensitive species declined evidently in the sites 1 and 2 and the tolerant species increased in the dam sites. Our outcomes may be used as a key data for diagnosis of the long-term ecological impact in the future in the watershed.

• The Korean Journal of Ecology
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• v.19 no.4
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• pp.253-261
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• 1996

This study was conducted to clarify the relationship between bird community and forest structure from early May to mid June, 1988 in two sites which had different forest structures due to silvicultural practice, located in the Tomakomai Experimental Forest of Hokkaido University, Hokkaido, Japan. Quantitative ahbitat analysis was applied to elucidate difference between the two study sites, and territory mapping method and guild analysis were used for assessment of the bird community. Dominant tree species were Quercus mongolica, Magnolia obovata, Prunus sargentii, Acer mono and Tilia japonica. Unithinned site had more foliage coverage in upper and middle layers, but in lower layer had less coverage than thinned site. Thirty four species of birds were recorded and of them only 21 species occupied territories within the study area. Dominant species were Ficedula narcissina, Phylloscopus occipitalis, Parus major, Passer rutilans, Sitta europaea and Parus palustris in the study area. The unmber of breeding species of the two sites were equal, but the species composition of breeding bird communities was different between the sites. The number of species and pairs on hole-nesting guild were greater in the unthinned site, but those on ground-nesting guild were greater in the thinned site. Canopy-nesting guild showed no significant difference between the two sites. Silvicultural practice such as proper thinning appeared to be not inadequate to all of the forest birds, probably good to bush and ground nesting guild, and to tree & bush and ground foraging guild. The silvicultural practice also did not considerably affect the hole and canopy-nesting guild.

• Animal cells and systems
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• v.12 no.3
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• pp.165-170
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• 2008

Cuticular hydrocarbons(CHCs) of the epicuticle wax layer are so far used to differentiate the insects in species and subspecies levels. In this study, four species of malaria vectors(genus Anopheles) were collected from various localities in southern Iran. Twenty specimens of each species were randomly selected and one epicuticular extract was prepared of every five specimens. FID-GC profiles of the extracts did not show any qualitative difference. Using significant difference of CHC mass at retention time(RT) 39.6, the two species of An. sacharovi and An. fluviatilis could be distinguished. Similarly, the two species of An. superpictus & An. sacharovi and An. dthali & An. sacharovi were differentiated by their CHC level at RT 28.5. An. sacharovi was distinguished by integratable peaks at RTs 29.7, 30.6, 30.7, 31 and 32.6 while the other three species just indicated trace peaks at the same RTs. Similarly, An. dthali could be known by an integratable peak at RT 26.2 while An. fluviatilis and An. superpictus indicated trace peaks at the same RT. Integratable peaks and traces at RTs 27.4 and 28.5 were respectively used to differentiate An. superpictus from An. fluviatilis. Lastly, CHC trace amount of An. superpictus at RT 39.6 is another indicator to distinguish it from An. fluviatilis with an integratable peak at the same RT. In harmony with other studies worldwide we hereby report that quantitative analysis of CHCs was successfully applied to differentiate the four Anopheles species of southern Iran.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.3
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• pp.246-255
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• 2017

The species composition and variation in abundance of fishery resources near Oenarodo, Go-heung Peninsula, Korea, were investigated by gill net, trap net, and longline in May, July, and October 2015 and 2016. During the study period, the total catch included 14 species in the gill net, 11 species in the trap net, and 4 species in the longline. The dominant species were Portunus trituberculatus and Raja pulchrain the gill net, Charybdis japonicaand and Octopus vulgarisin in the trap net, and Muraenesox cinereusin in the longline. The Catch Per Unit Effort (CPUE) per individual and per weight in the gill net were similar in May and July of 2015 and 2016. In October 2015, the CPUE per individual was 2.1 ind./h and the CPUE per weight was 505 g/h higher than the results in 2016, but there was no significant difference in the total CPUE between 2015 and 2016. In the trap net, the CPUE per weight was similar in both 2015 and 2016, but the CPUE per individual was 2.7 ind./h higher in October 2015 than in October 2016 and the total CPUE was not significantly different from 2015 to 2016. The CPUE per individual and weight in the longline were significantly higher in July and October 2015 than in the same months of 2016, but the total CPUE in 2015 and 2016 did not show a significant difference.

• 한국전산유체공학회:학술대회논문집
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• 1997.10a
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• pp.99-105
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• 1997

A finite-difference method based on conservative supra characteristic method type upwind flux difference splitting has been developed to study the nonequilibrium chemically reacting inviscid flow. For nonequilibrium air, NS-1 species equations were strongly coupled with flowfield equations through convection and species production terms. Inviscid nonequilibrium chemically reacting air mixture flows over Blunt-body were solved to demonstrate the capability of the current method. At low altitude flight conditions the nonequilibrium air models predicted almost the same temperature, density and pressure behind the shock as equilibrium flow: however, at high altitudes they showed substantial differences due to nonequilibrium chemistry effect. The new nonequilibrium chemically reacting upwind flux difference splitting mettled can be extended to viscous flow and multi-dimensional flow conditions.