• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.526-539
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• 2011

The purpose of this study is to identify insects inhabiting Mulyeongari-Oreum wetland and to provide basic information for conservation of wetlands. As a result, a total 229 species, 73 families, 9 orders of insects were collected: 136 species, 39 families, 6 orders from Mulyeongari-Oreum Wetland and 121 species, 52 families, 9 orders from Mt. Sooryeong. Of the 229 species of insects investigated, Copris tripartitus Waterhouse, an endangered species of wildlife fauna in Korea, was found with many individuals. Also, Lychnuris rufa(Olivier), having a narrow habitat near unpolluted water and mountains, was also recorded with 3 individuals and then should be considered as a protected species in Wetlands. To identify the community structure of moth on Mulyeongari-Oreum wetland, a light trap was examined and a total 76 species of moths were collected. Total dominant species was Hydrillodes morosa(Butler) with index of 0.12 and the species diversity on the moth community from survey area was the highest in July with index of 3.42.

• Journal of Sericultural and Entomological Science
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• v.20 no.2
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• pp.20-25
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• 1978

Research on the hormones of insect has followed by the special opportunities and problems arising from pollution. Since then, the main frame of it has been energetically exploited by ligation, decapitation and so on. In the meanwhile, knowledge of the biochemistry of hormone action as well as other aspects of biochemistry in insects has been gradually disclosed. Since 1966, practical use of active analogs of the hormones has been also worked out as an insecticide and brought the features of it to the light. On the other hand, it is expected to afford the increase of silk productivity resulted from control of the fifth larval period by delaying normal development. With these regards, some of analogs have been tried to apply practically to the silkworm. One of them is "Manta" produced by Zoecon Chemical Company and it is presently used for the increase of silk productivity in Japan. Another one is "R-20458", not registered one, issued by Stuffer Chemical Company. It is still pending for the silkworm growth regulator For the possibility of practical use, two chemicals are tested on the increase of silk productivity by topical application and the obtained results are summarized as follows. 1. It is evident that the fifth larval period was extended by topical application of the tested chemicals "Manta"and "R-20458"at the fifth instar after 51 hours of the last ecdysis, ranging from 12 hours to one day, as compared to. the control 2. In survival rates, there is no significance at 5% level between control and treatments. It proved that there was no toxity to silkworm by topical aprication. 3. There is an increase of cocoon yield in both chemical treatments. It was resulted from increase of weight of single cocoon. "Manta"2.5ppm produced 22.2kg of cocoon. It is equal to 9% increase in index, as compared to that of control. In case of R-20458, the increasing rates were varied at the different concentration; 21.4kg of cocoon production with 5% increase at 5ppm, 20.9kg of it with 2% increase at 2.5ppm and 20.6kg of it with 1% increase at 1. 25ppm in index, respectively, as compared with that of control. 4. Percentage of cocoon shell was increased by topical application. In case of "Manta" 2.5ppm, it is 25.6% which is equal to 6% increase in index, as compared with that of control. For "R-20458", the increasing rates of percentage of cocoon shell were varied with the different level of chemical concentration. They are 25.0% of 4% increase at 2.5ppm, 24.9% of 3% increase at 1.25ppm and 24.7% of 3% increase at 5ppm. 15% increase was attained at "Manta" 2.5ppm in the weight of cocoon layer based on cocoon yield and percentage of cocoon shell in index, as compared with that of control. The rates for "R-20458"are 5% increase at 2.5ppm and 4% increase at 1. 25ppm in index.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.394-399
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• 2004

The species composition and abundance of aquatic insects were investigated by light trap in summer, 2002 at three stations in the Chikuma River, Japan's longest river. A total of 3278 adults/day were collected, the great majority (57.5%) of which were Diptera, followed by Trichoptera (35.4%) and then Ephemeroptera (7.1%). The number of collected aquatic insects and their biomass gradually increased towards downstream, whereas the number of species and species diversity index (H') decreased. 36 species (H'= 4.30) of aquatic insects were collected at St. 1, versus 31 species (H'= 2.81) at St. 3. Moreover, the relative abundance of functional feeding groups changed from St. 1 to St. 3, i.e., 'collectors' increased and 'shredders' decreased.

• International Journal of Industrial Entomology and Biomaterials
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• v.19 no.2
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• pp.243-248
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• 2009

The Larval critical weight is the minimal mass at which further growth in not necessary for a normal time course to pupation. Larval critical weight (Lcw), pupal critical weight (Pcw) and adult critical weight (Acw) of different breeds of Bombyx mori L. were determined through starvation (food deprivation). The Lcw was found to be about 938.46, 2397.26, 2283.57 and 2220.97 mg in males and 1118.15, 2681.04, 2604.9 and 2455.88 mg in females of the multivoltine breed (Nistari), Bivoltine breeds (P5 & NB18) and their hybrid (P5$\times$NB18) respectively. Bivoltine breed P5 took more time (3.35 days) followed by NB18 (3.13 days) & P5$\times$NB18 (3.02 days) to attain larval critical weight (In $5^{th}$ Instar) than the multivoltine breed Nistari (2.42 days). Decrease in weight from larval maximal weight to pupal weight and to adult weight was also observed more in multivoltine than bivoltines, which may be due to more latent feeding period in bivoltines. Since Lcw is a stable character and independent of environment, it could be utilized for characterization of silkworm breeds to assess the quality of an insect.

• Journal of Wetlands Research
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• v.7 no.4
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• pp.51-65
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• 2005

The insects and Benthic Macro-Invertebrates are very important for index of investigation. This reserch is executed a field investigation with a date analysis of the laboratory under such as above hypothesis and we have grasped the change of the creature according to the season through the executing of field investigation(We executed six times about the insects, seven times about the Benthic Macro-Inbertebrates each expending from Apr. to Oct. 2004). The result of summary in 2004 show that, we have grasped 12 orders 56 familys 116 species on 2001 and 10 orders 42 familys 78 species on 2002 through the investigation. Also we have grasped 13 orders 53 familys 114 species on 2003 and 12 orders 63 familys 121 speceies on 2004 through the investigation. In the case of enthic Macro-Invertebrates, we executed the analysis through the investigation result expending from 2003 to 2004 due to there is no literature investigation record from 2001 to 2002. We have grasped 8 orders 17 familys 24 species on 2003 and 7 orders 11 familys 24 species on Aug. 2004 through the investigation. We executed the analysis about an each condition due to it is difficult to compare the above result simply by the various variable at the investigation. We expect that it become the fundamental reference data to establish a efficient mode of life undo plan after grasped the inhabitation and movement route of creature inside the river through this reserch.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.366-370
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• 1992

Salient chromosomal variations during the first meiotic division in primary spermatocyLes of the three brown planthopper, Nilaparvata lugens (Stal) , biotypes were observed. The meiotic index was highest in biotype 3 (58.6), followed by biotype 1 (39.4) and biotype 2 (23.6). Total chromosomal aberration including agmatoploidy, aneuploidy, loose pairings of sex chromosomes, and cytoplasmic shrinkage was found high in the order of biotype 1 (60.6%),2 (47.9 %), and 3 (38.1 %). However, percent agmatoploidy was highest in biotype 2 (19.6%) whereas in biotypes 3 and 1, it was 9.5% and 2.5%, respectively. The number of cells with isolated sex chrosomomes was observed highest in biotype 2.

• Korean Journal of Remote Sensing
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• v.31 no.5
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• pp.385-394
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• 2015

Pine wilt disease has greatly damaged pine forests not only in East Asia including South Korea and China, but also in European region. The damage caused by pine wood nematode (Bursaphelenchus xylophilus) is expressed in bundles within stands and rapidly spreading, however, present field survey methods have limitations to detecting damaged trees at regional level. This study extracted the damaged trees by pine wilt disease using time series hyperspectral aerial photographs, and analyzed their distribution characteristics. Hyperspectral aerial photographs of 1 meter spatial resolution were obtained in June, September, and October. Damaged trees by pine wilt disease were extracted using Normalized Difference Vegetation Index (NDVI) and Vegetation Index green (VIgreen) of the September photograph. Among extracted damaged trees, dead trees with leaves and without leaves were classified, and the spectral reflectance values from the photographs obtained in June, September, and October were compared to extract new outbreaks in September and October. Based on the time series dispersion of extracted damaged trees, nearest neighbor analysis was conducted to analyze distribution characteristics of the damaged trees within the region where hyperspectral aerial photographs were acquired. As a result, 2,262 damaged trees were extracted in the study area, and 604 dead trees (dead trees in last year) with leaves in relation to the damaged time and 300 and 101 newly damaged trees in September and October were classified. The result of nearest neighbor analysis using the data shows that aggregated distribution was the dominant pattern both previous and current year in the study area. Also, 80% of the damaged trees in current year were found within 60 m of dead trees in previous year.

• Korean Journal of Environment and Ecology
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• v.27 no.2
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• pp.196-203
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• 2013

Butterfly communities were monitored to investigate the emergence pattern with line transect method at Wolchulsan National Park through May to October in 2012. Totally 1,151 individuals belong to 49 species were monitored through the study period. Libythea celtis was a dominant species with showing 357 individuals(31%) followed by Pseudozizeeria maha 96 individuals(8.3%), Mycalesis gotama 75 individuals(6.5%) and Ninois dryas 72 individuals(6.2%) respectively. Among the monitoring periods, highest individuals and species(516 individuals belong to 30 species) were found at June and showed a high abundance near reservoir region. Highest diversity was shown at August with a Shannon index of 2.75 while lowest at October(Shanon index 1.78) and total diversity index was 1.71. Dominance values(Simpson index) showed highest at June with a value of 0.40 while lowest at September with a value of 0.07 and averaged 0.12. Kungol and Seongjeon compose a high similarity habitats with a similarity value of 0.52 and it was 0.17 at Kungol and Youngsan, lowest cases. Reservoir banks played a important role for habitats of specific species. It can be considered that they provide an open space of glass land for butterfly population, which was deficient at mountain area.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.319-325
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• 2014

A lot of Pond Wetland (Palustrine Wetland) are distributed in agricultural landscapes, Korea. These wetlands are evaluated as important resources for conservation of biodiversity. However, the study of Pond Wetland is rarely conducted except type classification in Korea. In this study, the function of pond wetland as ecosystem services is studied for conservation and utilization of wetland. Research was conducted in three steps; functionality analysis, functionality derivation, and importance analysis. A total of 22 features were derived by analyzing the previous studies. As a result of expert survey, 4 features were selected by each in the field of biological, environmental, and socio-culture among the 22 features. Importance was calculated by conducting a cross-functional features using Analytic Hierarchy Process (AHP). Finally, 10 ecosystem service functions of pond wetland were derived through expert survey; (1) Water Storage & Irrigation, (2) Vegetation Diversity, (3) Amphibian & Reptile Habitat, (4) Water Purification, (5) Aquatic Insect Habitat, (6) Nutriments Control was derived, (7) Groundwater Recharge, (8) Fishery Habitat, (9) Eco-Experience & Education, and (10) Aesthetic landscape. It is expected that this study is able to utilize in evaluation of pond wetlands ecosystem services by further study on analysis of functional importance and economic value index.

• Journal of Korean Society of Forest Science
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• v.50 no.1
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• pp.56-71
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• 1980

To study the changes of vegetational composition of each plant successional stage of Pinus densiflora forest caused by pine gall midge damage, Thecodiplosis japonensis, located in Kyonggi-do area, the middle part of Korea, four districts, Anseong, Yongin, Gwangju, and Gapyeong, were selected according to the length of insect damage duration. The forest in the Anseong district was the noninfested one selected as the check. And forests in Yongin, Gwangju, and Gapyeong were the recent]y damaged, severely damaged, and damage prolonged ones in sequence. It was considered that this order could be in concord with the gradual transition of plant successional stage. In view of temperature, precipitation and soil factors, these four districts were sited within the same environment. Four survey plots were selected from each district and the distance between them was 3~4 km. Then again four subplots were set within a plot. Through needle accumulation after insect infestation, light intensity, soil moisture content, and the amount of soil organic matter were increased and these conditions could create a favorable environment enabling the new species invasion and their growth. These were naturally closely related with the increase in quantity of Pinus densiflora defoliation. After considerable time lapse, the quantities of above mentioned factors decreased with the development of the new substitute tree species. It was found that Quercus mongolica was an excellently substitute tree species come first in this studied area. Species diversity increased to a degree at the early stage of the duration of pine gall midge damage and decreased thereafter. As the same manner, similarity index value between plots in the same district decreased to a degree and increased thereafter. This was linked admittedly with the increase and decrease of tree species and evenness. Synthesizing above mentioned results, the process of plant succession studied quantitatively by changes of relative density and relative importance value, it can be concluded that Pinus densiflora forest gives way to Genus Quercus forest in which Genus Lespedeza and Genus Rhododendron species become as subdominance species after removal of the Pinus densiflora trees damaged by pine gall midge.