• Korean journal of applied entomology
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• v.28 no.2
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• pp.61-68
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• 1989

To investigate the possibility of the BPH control by systematic application of insecticides, biological effects of buprofezin and isoprothiolane upon the BPH population was evaluated in the laboratory and pot. Both chemicals did not affect the developmental period of the nymphal stage with the applied dosages. When the buprofezin treated instar nymph was developed to the adult, adult's longevity was fairly reduced and such an effect of buprofezin was greater upon the younger instar nymphs. Residual effect of buprofezin was about 30 days in the pot. And it could suppress the BPH population when the younger instar nymphs were dominant age group in the population at the time of treatment. Isoprothiolane was also more effective for the suppression of the BPH population when the younger instar nymphs were dominant at the time of treatment. And it was expected that by buprofezin treatment in July the control effect of isoprothiolane against the BPH population could be maximized when it was treated to control the rice neck blast in late July or early August, because buprofezin could induce the biased population age distribution in which younger instar nymphs were main group at the time of isoprothiolane treatment.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.552-563
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• 2015

The characteristics of ichthyofauna and fish community in Lake Goesan were examined from April 2010 to October 2012. During the survey period thirty six species belonging to 11 families were collected. Dominant species by number were Hemibarbus labeo (29.9%) and Zacco platypus (20.0%). In biomass, the dominant species were H. labeo (37.2%) and Carassius auratus (17.9%). Also, fourteen Korean endemic fish species (38.9%) and one endangered species (Acheilognathus signifer) were collected. Further, one catadromous species was observed for stock enhancement (Anguilla japonica), in addition to two land-locked anadromous species (Hypomesus nipponensis, Plecoglossus altivelis) and three exotic species (Cyprinus carpio (Israeli type), C. cuvieri, Micropterus salmoides). According to the length-weight relation of C. auratus and M. salmoides, the b values were 3.13~2.99, 3.11~2.99, showing a declining tendency annually. However, for H. labeo and Z. platypus, the b values were 2.98~3.07, 3.06~3.23 respectively, showing an increasing trend. The slope values for C. auratus and M. salmoides population conditions were controlled by K factor showing a tendency to decrease, but H. labeo and Z. platypus were showing a tendency to gradually increase.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.937-943
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• 2007

The fish fauna and weight-length relationship in Andong reservoir were investigated from May 2005 to March 2006. During surveyed period, 2,540 individuals 20 species belonging to 7 families were collected. Dominant species were Hemibarbus labeo(19.6%) and sub-dominant species were Carassius cuvieri (19.2%). The korea endemic species were Hemiculter eigenmanni(7.1%), Squalidus chankaensis tsuchigae (0.1 %), Corroperca herzi (0.1 %) and introduced fishes were Carassius cuvieri (19.21 %) Lepomis macrochirus (4.2%), Micropterus salmoides (0.2%). Dominace, species diversity, species richness, species even-ness were 0.39, 3.16, 2.42, 0.73 respectively. The values of the exponent b in the weight-length relation-ship $W=aL^{b}$ ranged from 2.9162(H. labeo, $R^{2}$=0.9567) to 3.2509(Zacco pla쇼pus, $R^{2}$=0.9928) and the median value was 3.1079, whereas 50% of the values ranged between about 3.05 to 3.20. The Condition factor(K) showed good state of health in the surveyed species (excepts H. labeo and Cyprinus carpio).

• Journal of Wetlands Research
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• v.16 no.3
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• pp.303-313
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• 2014

The spatial distribution characteristic of fish community were investigated at the 10 habitat types in the Nonsan stream from August, 2008 to June, 2009. The collected species during the surveyed period were 26 species belong to 6 families. Korean endemic species were Sarcocheilichthys nigripinnis morii, Squalidus japonicus coreanus, Hemiculter eigenmanni, Pseudobagrus koreanus, and Odontobutis interrupta which showed 19.2% ratio of total species. Dominant species was Zacco platypus, and subdominant species was Tridentiger brevispinis. Dominant species according to habitat types were Micropterus salmoides(substrate type pool and rock type pool), Lepomis macrochirus(channel connected pool and channel unconnected pool/abandoned type pool), T. brevispinis(channel unconnected pool/overflow type and run) and Z. platypus(riffle, meander type pool, side channel, and dam type pool). As a results of community analysis in side channel, diversity index showed relatively high values, indicating that habitat types in the Nonsan stream have relatively stable community structure. Bray-curtis cluster analysis indicated that the meander type pool and riffle showed the most similar values(80.8%). Moreover, cluster and principal component analysis were classified as 2 groups(lotic and lentic habitats).

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.219-228
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• 2015

Purpose: The current study was performed to compare the difference in binocular visual function depending on variable background colors at near work. Method: Fifty four adults (18 males, 34 females) who consented to the present study and had no ocular disease, ocular surgery history, strabismus and amblyopia with normal binocular vision were participated into this study. The subjects were asked to read the novels with black letter printed on white, red, green and blue background for 15 min. Then, their heterophoria, AC/A ratio, near point of convergence, accommodation facility, relative accommodation and vergence were measured before and after reading. The difference of measurements were compared. Result: Overall heterophoria was tended to decrease with regardless of background color. AC/A ratio showed a tendency of increase after reading the novels with all backgrounds except white background. Near point of convergence was significantly increased compared to before reading at all background color. Accommodative facility of dominant and non-dominant eyes were also significantly increased after reading however, binocular accommodative facility showed a tendency of decrease. Negative relative accommodation also decreased at all background colors however, the change of positive relative accommodation was not significantly different. In case of vergence, there was significant difference in break point of far BO and recovery point of far BI by the wavelength of background color. Conclusions: From the results, it was known there is convergence change depending on the wavelength of light even though same amount of accommodation and convergence is required when doing near work for certain period. Thus, it can be suggested that the adjustment of the near working environment which perception of various color was required, should be conducted according to the main wavelength.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.633-642
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• 1994

Distribution of ichthyoplankton in the adjacent waters to Kori were surveyed during the period from April, 1991 to January, 1992. The dominant fish eggs included the eggs of Engraulis japonica, Maurolicus muelleri, Callionymus spp. and others. The eggs of Engrualis japonica and Maurolicus muelleri were $79.52\%$ and $1.86\%$ of the total eggs abundance, respectively. A total of 15 taxa of fish larvae were found. The dominant species was Engraulis japonica accounting for $52.39\%$ of the total larvae and followed by Callionymidae fish($29.36\%$). Other major species were Stephanolepis cirrhifer($6.30\%$), Sebastes schlegeli($3.16\%$), Ammodytes personatus($1.33\%$) and Girella punctata($1.70\%$). These 6 taxa constituted $94.30\%$ of the total larvae collected. In this area, distributions of warm water had a great influence on larvae and juvenile distribution which usually is along the coast and the other places where there layer water movements since, upwelling in the open sea affects ichthyoplankton distribution.

• Korean Journal of Ichthyology
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• v.21 no.1
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• pp.38-46
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• 2009

The ichthyofauna in certain reservoirs in Gyeongju-si, Gyeongsangbuk-do were studied from August 17 to September 22, 2005. During the study period, 22,747 individuals belonging to 25 species, 20 genera, 9 families and 4 orders were collected. Of these, 14 species were cyprinid fishes, and the dominant species was Pseudorasbora parva (relative abundance 52.28%). There were six Korean endemic species (8.51%), including Sarcocheilichthys variegatus wakiyae, Squalidus chankaensis tsuchigae, Squalidus mulimaculatus, Hemiculter eigenmanni, Pseudobagrus brevicorpus and Odontobutis platycephala the dominant species was Squalidus chankaensis tsuchigae (7.59%). There were six introduced species (25.00%), of which Hemiculter eigenmanni, Pseudobagrus fulvidraco and Hypomesus nipponensis were introduced from other native stream systems (20.99%), and Cyprinus carpio (Israeli), Carassius cuvieri and Lepomis macrochirus were exotic species (4.01%).

• The Korean Journal of Soil Zoology
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• v.5 no.1
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• pp.21-32
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• 2000

A faunistic study on the spiders (Arachnida: Araneae) from Mt. Jumbong Kangwon-do was carried out from 1996 to 1999. During the survey period, 144 species of 88 genera belonging to 27 families including 5 undetermined species were identified from 900 collecting individuals. The dominant families were Linyphiidae 21 species; 14.6% of total species), Araneidae (20 species, 13.9%), Theridiidae (16 species, 11.1%), and Salticidae 12 species, 8.3%). The composition of the species of web builders was richer than that of hunters. As for species commonness with adjacent countries, the numbers of common species between Mt. Jumbong and Japan, Mt. Jumbong and China, and Mt. Jumbong and Russia were 15 species (80.4%), 98 species (68.5%), and 48 species (33.6%), respectively. The number of common species among these four regions were 39 species (27.3%). So, the spider species composition in Mt. Jumbong seemed being much similar to those in neighbor countries. An outline of biogeographical distribution of spiders can be summarized as 1 Cosmopolitan species (0.7%), 16 Palearctic species (11.2%), 7 Holarctic species (4.9%), 25 Korean endemic species (17.4%) and no Oriental species. In the spider fauna at Mt. Jumbong, therefore, there are high level of occurrence of Korean endemic species with northern spiders as Palearctic and Holarctic species. The level and direction of man-made development may have negative effect on regional biota.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.478-485
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• 2013

Fish field survey, especially fish distribution and their ecological characteristics, was performed in the downstream region of Gyeongan stream during the period of before (June) and after (October) the summer monsoon in 2010. Depending on the characteristics of each site, fyke net or casting net was used for fish sampling. Feeding classification was determined by the analysis of stomach contents. Total number of family and species sampled were 5 and 17, respectively. The dominant family was Cyprinidae (12 species), and relative abundance (RA) of the most dominant species, Lepomis macrochirus and Zacco platypus, was 38% and 24%, respectively. Exotic species and Korean endemic species observed were 3 (423 individuals, RA 44%) and 4 (98 individuals, RA 10%), respectively. Tolerance guild analysis as characteristics of ecological indicators revealed an undoubtedly high percentage (97%), compared to others as reflected by the identification of just one sensitive species. Analysis of trophic guilds showed that L. macrochirus dominated among insectivores (44% RA). The food of L. macrochirus composed of, aquatic insects, benthic invertebrates, zooplankton, Chironomidae, and waterweed. Thus, we determined that L. macrochirus could be classified as insectivores (partially carnivores) in this study. Conversely, Z. platypus consumed Cladocera exclusively, greater than 90% of their feed. We presume that stable isotope analysis would identify the exact position of these species in the food web.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.715-722
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• 2002

The monthly collected fish samples by crab pots were analyzed in order to study the species composition and seasonal variation of fish assemblage in the coastal water off Gadeok-do, Korea in 1998, During the study period, 49 species of fishes representing 26 families were collected, The dominant species were Conger myriaster, Sebastes inermis, Hexagrammos otakii, H. agrammus, Stephanolepis cirrhifer and Acanthogobius flavimanus. These 6 dominant species accounted for $67.1\%$ and $69.4\%$ in the number of individuals and biomass, respectively. The secondary importance species were Thamnaconus modestus, Takifugu niphobles, Rudarius ercodes, Dictyosoma burgeri, Sebastes longispinis and Epinephelus septemfasciatus. The highest number of species was collected in November, and the number of individuals and biomass were highest in March. But the lowest numbers of species and individuals were collected in July and the lowest biomass in September, Although the species diversity indices varied little monthly, the lowest value was recorded in August because of small number of species and predominance of 5. cirrhifer and T. modestus.