• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.294-304
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• 2023

Seasonal variations in the community structure of larval fish assemblage in the coastal waters off Gadeok-do were investigated in May, August and November of 2019, and February in 2020. During the study period, a total of 85 larvae species belonging to 45 families were collected. The dominant species were Engraulis japonica, Gobiidae sp., Clupea pallasii, Decapterus maruadsi, and Callionymidae sp.. These five species accounted for 84.1% of the total number of larvae during the survey period. E. japonica, Gobiidae sp., D. maruadsi, and Callionymidae sp. were the dominant species in the summer, while C. pallasii was the dominant species in the winter. The Species Diversity Index was highest in the summer and lower in the fall and winter months, with the lowest values in the spring. As a result of cluster analysis using the number of individual larval fish showed that they are divided into four seasonal groups. In particular, due to seasonal changes in water temperature, an appropriate growth environment was formed in the summer, and an appropriate hatching water temperature for winter spawning fish species was formed in winter, reflecting the seasonal characteristics of the larval fish community.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.21-27
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• 2017

This study was investigated in order to occurrence of weed flora in orchard (apple, grape, peach, pear etc.) fields and to the establishment of weed control basic data in these weeds. And this study was survey on 2015. As a result of the study on orchard weeds, there were total of 492 weeds including 63 families. Among all the weeds, 159 species were annual, 97 species were winter annual and 236 were perennial. Each fruit tree patterns of occurrence weeds, 306 species 50 families in apple orchard, 304 species 50 families in pear orchard, 286 species 50 families in grape orchard, and 288 species 48 families in peach orchard. Dominance was the highest with Digitaria ciliaris followed by Artemisia princeps, Stellaria aquatica, Commelina communis, Acalypha australis etc. in order. And exotics weeds occurred 127 species. Trifolium repens was the highest in importance analysis and the followings were in order of Conyza canadensis, Chenopodium album, Taraxacum offcinale, Rumex crispus etc. Changes in weed vegetation in orchard during 30 years, did not very many changed. In 1990, D. ciliaris, Persicaria hydropiper, Portulaca loeracea were dominant. In 2003, D. ciliaris was the most abundant species, followed by A. australis, A. princeps species. And in 2015, also D. ciliaris was the most dominant, followed by A. princeps, S. aquatica.

• Korean Journal of Environment and Ecology
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• v.38 no.3
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• pp.263-276
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• 2024

Fish community characteristics and the influence of sampling gear were investigated in Lake Singal, South Korea, from August 2020 to October 2021. The employed sampling gears included a kick net, cast net, gill net, and fyke net, which are commonly utilized within the lake. Across three survey stations, a total of 18 fish species from seven families, comprising 3,501 individuals and contributing to a total biomass of 117,670 grams, were identified. Dominance among species was assessed based on individual count and biomass. Pseudorasbora parva was the most abundant, constituting 29.9% of the total catch, followed by Zacco platypus (25.1%) and Micropterus salmoides (19.3%). In terms of biomass, Carassius auratus was predominant, accounting for 45.1%, followed by Cyprinus carpio (17.4%) and M. salmoides (14.3%). Among the sampled species, three were identified as endemic to Korea: Squalidus japonicus coreanus, Cobitis nalbanti, and Odontobutis interrupta. Additionally, four exotic species were recorded, including M. salmoides and Lepomis macrochirus, both classified as invasive alien species, along with C. cuvieri and a variant of Cyprinus carpio (nudus type). Analysis of the average standard length (SL) and body weight (BW) revealed significant size variations among species. P. parva, the dominant species, measured 60 ± 24.1 mm (SL) and weighed 4.4 ± 3.42 g (BW). The subdominant species, Z. platypus, exhibited an SL of 82 ± 17.6 mm and a BW of 10.4 ± 7.27 g. M. salmoides, another dominant species, registered 96 ± 25.1 mm (SL) and 24.9 ± 96.02 g (BW), while C. auratus measured 125 ± 77.3 mm (SL) and weighed 168 ± 336.5 g (BW). In terms of gear-specific performance, the kick net captured eight species from three families, totaling 302 individuals with a biomass of 1,269 g. The cast net was more effective in coastal zones, collecting 11 species from four families, amounting to 948 individuals and 31,343 g of biomass. The gill net yielded the highest biomass, capturing 13 species from four families with 682 individuals weighing 69,695 g. The fyke net recorded the highest species diversity and number of individuals, capturing 15 species from seven families, totaling 1,569 individuals and 15,362 g of biomass. The fyke net proved most efficient in species and individual counts, whereas the gill net was superior for biomass collection. Conversely, the kick net demonstrated effectiveness in collecting small benthic species in coastal areas.

• Journal of Families and Better Life
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• v.11 no.2
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• pp.83-95
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• 1993

This study investigated time management behavior of employed wives and variables related. The samples were composed of 396 wives living in Seoul and Kwangju city. The major finding are as follow: 1) The level of the time management of employed wives was slightly high. 2) The dominant factor in time management behavior was goal setting and planning$.$priori-ting 3) The time management behavior was low related to the time use. A negative relationship was found between time management behavior and psysiological time employed time psysical housework time and passive leisure time while a positive relationship was found managerial housework time and active leisure time 4) A employed wife with higher work status education and income level efficiently managed time Education and extend family type turned out facilitating factors the more employed time was found constraint factor in time management.

• Journal of Families and Better Life
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• v.24 no.1 s.79
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• pp.1-9
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• 2006

The purpose of this research is to identify stereotypes toward the mother-in-law held by female students. Stereotypes toward the mother-in-law were examined at two levels: to assess female students' beliefs about the traits of mother-in-law and to categorize the traits into stereotypes. The main results of this study were as follows: 1) Students reported 91 traits associated with the mother-in-law. 2) Hierarchical cluster analysis of the trait groupings revealed two high-level clusters: a cluster of 42 positive traits and a cluster of 49 negative traits. Within the positive and negative clusters, 14 middle-level categories, 6 positive categories(tough, leisurely, traditional image of prudent elders, image of the eldest in the family, intimate, tolerant), and 8 negative categories(dominant, self-assertive, cold, discriminating, fearful, mean, sadistic, authoritative, nervous) were identified. This results suggested that female students believed negative stereotypes are more typical than positive ones.

• Korean Journal of Environmental Biology
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• v.20 no.3
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• pp.263-267
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• 2002

The faunistic study on the spiders (Arachnida, Araneae) from Quito and Galapagos Islands was carried out from 1st to 18th Aug. 2000. During the survey period, 50 species of 48 genera belonging to 22 families (include 1 undetermined species) were identified from 562 collecting individuals. The dominant family was Araneidae (Gasteracantha cancriformis : 32% of total species). The species of settling spiders were richer than those of hunting spiders among the identified spiders. The author redescribes and figures in detail Gasteracantha cancriformis, which was collected during a field trip of Quito and Galapagos Islands.

• The Korean Journal of Ecology
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• v.14 no.3
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• pp.345-360
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• 1991

Benthic macroinvertebrates were collecte in the middle reaches of the paenae stream, a tributary of th naktong river in korea, in four seasons from August 1989. To may 1990, during the study period, 125 species, 81 genera and 41 families were collected. Overall, the most dominant species was lepidostoma sp. 1 followed by heptagenia kihada, neoperla quadrata, diamesa sp. 1, ect.. the community was most diverse in autumn, However the number of collectd individuals was highest in winter. Species of chironomids including diamesa sp. 1 and mayflies including paraleptophlebia chocorata were collected exceptionally in a large number in winter. Seasonal occurrence of funtional groups such as collectors, shredders and scrapers was related with the availadlity of food sourses in the stream. The abundance of predators was relatively stable in four seasons with 17% on average. Diversity, tbi and chandler's biotic score(bs) in the paenae strem were 3.75, 14.5, and 100 on average, respectively. Based on biological and chemical indices the paenae stream was clean in the range of xeno- and oligo- saprobity.

• The Korean Journal of Ecology
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• v.14 no.2
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• pp.181-194
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• 1991

Vascular plants, the structure and interrelationship of the forst vegetation in pyonsan peninsula national park were inverstigated by phytosociological, continuum analysis and ordination methods. The flora was composed of 119 families,411 genera, 609 species, 79 varieties, 10 forma or 698 taxa. Some characteristics of the plants have been represented such as ch-$D_1$-$R_5$ type in biological one, erect form in growth on. It is noticeable that lycoris aurea, carpinus tschonoskii var. eximia, corylus hallaisanensis and abeliophyllum distichun among the investigated plants delong to endemic and/or rare species. The forest vegetation was classified into seven communities: quercus variabilis, pinus densiflora, quercus serrat, platycarya, carpinus tschonoskii, quercus dentata, zelkova serrata community. and quercus variabilis, pinus densiflora and pinus rigida, were the commonest species among distributed species. In addition interrelationship between diversity and dominant indrx of quercus variabilis community was little different each other and that of accordance altitude also was not much distinguishable. Platycarya strobilacea, pinus densiflora and quercus variabilas community were distinguished different groups by polar ordination.

• The Korean Journal of Ecology
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• v.10 no.2
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• pp.53-62
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• 1987

Floristic composition and vertical distribution of Mt. Daedun (western slope) were investigated from 1985 to 1986. The results are as follows; 108 families, 346 genera, 511 species, 2 subspecies, 75 varieties, 5 forma or 593 taxa including 77 cultivars. The floral data showed the ecological characteristics such as the value 346 in Fisher's Index, H-D1-H5 in biological type, 10.9% in urban index of naturalized plants and 60.5% in erect form growth form. Based on the physiognomy and population density of dominant tree species the forest vegetation of Mt. Daedun (western slope) was classified into 5 types; Quercus mongolica forest and Q. variabilis forest at 800m above, Carpinys laxiflora forest and Acer mono forest at 700m to 800m and Sapium japonicum forest at 500m to 800m in altitude. And Lindera erythrocarpa forest and zelkova serrata forest are widely distributed at 400m to 800m in altityde along valley and at mountain foot area.

• The Korean Journal of Ecology
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• v.13 no.4
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• pp.267-283
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• 1990

The studies on the dynamics of fish communities in Manggyong River estuary were carried out from September 1989 to August 1990. The results, the fishes of 77 species belonging to 66 genera and 37 families were collected and identified. The dominant species in surveying areas were Thrissa koreana, Harengula zunasi, Synechogobius hasta and Konosirus. T. koreana was grown up to about 110mm of toatl length for a year, H. zunasi about 120mm, K. punctatus about 160mm and S. hasta about 220-460mm, respectively. The spowning season of S. hasta was from March to April, K. punctatus from April to June, H. zunasi from May to June and T. koreana from June to July, respectively. T. koreana and S. hasta belonged to to carnivorous, K. punctatus herbivorous and H. zunasi showed feeding habits of omnivorous fishes.