• Journal of agriculture & life science
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• v.44 no.1
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• pp.43-49
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• 2010

Life history of Gampsocleis sedakovi abscura Walker, an amenity sound producing insect, was investigated in Jinju, Korea from 2005 to 2007. G. sedakovi abscura had a generation per year and could be seen in the field from early March to late September. The peak emergence period of adults was early July. Developmental period from egg to adult was 357 days in average of three years in the field. Egg and nymphal periods, and adult longevity were 269, 88, and 357 days in average, respectively. The average ovipositional period was 63 days, and an adult laid 94 eggs in average throughout her life. The average longevity of adult was 90 days for female and 82 days for male. The sex ratio was 52%. G. sedakovi abscura over-wintered as egg stage in the soil. Circadian rhythm of the adult emergence showed that more than 70% of the adults emerged in the morning.

• The Journal of the Petrological Society of Korea
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• v.24 no.4
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• pp.323-335
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• 2015

Although the Daljeon Basalt in the Pohang Basin is important for interpreting the basin evolution, its relative chronology, stratigraphic position, and isotopic age still remain controversial. In order to clear up the controversies, this study carried out detailed field investigation to determine its distribution and occurrence together with reanalysis of its previous geochemical data and $^{40}Ar/^{39}Ar$ age dating. Based upon the field investigation, the basalt occurring in the central part of the Pohang basin is composed of three main bodies and a dozen of minor dikes and sills that intruded into the Yeonil Group. Their mineral assemblages consist of phenocrysts such as olivine and clinopyroxene and fine groundmasses of clinopyroxene, plagioclase, olivine, and opaque oxide, impling the porphyritic texture of alkaline basalt. All their geochemical data also show the similar geochemical characteristics in TAS, Zr-Ti, and REE/trace elements distribution diagrams. The samples are plotted on alkalic field in the total alkali-versus-silica diagram and show similar patterns to enrichment oceanic basalt or within plate basalt in trace elements. In addition, $^{40}Ar/^{39}Ar$ isochron age of 13.82Ma is obtained. These results indicate that the Daljeon Basalt is an alkaline intrusive rock belonging to the middle Miocene Yeonil Group.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.17-22
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• 1988

Inhibitory effect of L. leptolepis fallen leaf extracts on the germination of Pinus densiflora, ${\times}$ Pinus rigitaeda, Pinus rigida, Pinus thunbergii and Larix leptolepis was investigated. Germination of those seeds in culture room and in pot at field showed the highly significant inhibitory effects by the aqueous extracts from L. leptolepis fallen leaves. Among them L. leptolepis was the most severely inhibited by the aqueous extracts used. To identify allelopathic substances, thin-layer chromatography was employed. Gallic, ferulic, t-cinnamic and vanillic acids were identified from fallen leaves of L. leptolepis. From the results, it is assumed that autotoxicity of L. leptolepis may act as inhibitory factors on germination of the species in natural stands.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.81-99
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• 2018

Excessive groundwater discharge by tunneling and tunnel operation can lead to groundwater exhaustion and ground subsidence. Therefore, it is very important to evaluate environmental impact and to establish mitigation measures of the impact related to tunnel excavation based on hydrogeological and modeling approaches. This study examined the depletion of surface reservoirs and valley water due to tunnel excavation through field survey, water quality analysis, tracer test, and groundwater modeling. As a result of field water quality test, the concentration of chemical constituents in groundwater discharge into the tunnel is slightly higher than that of valley water. By the result of laboratory water analysis, both valley water and the groundwater belong to $Ca^{2+}+HCO_3{^-}$ type. Tracer test that was conducted between the valley at the injection point and the tunnel, indicates valley water infiltration into the ground and flowing out to the tunnel, with maximum electrical conductance changes of $70{\mu}S/cm$ in the first test and of $40{\mu}S/cm$ in the second test. By groundwater modeling, the groundwater discharge rate into the tunnel during tunnel construction is estimated as $4,942m^3/day$ and groundwater level recovers in 3 years from the tunnel completion. As a result of particle tracking modeling, the nearest particle reaches the tunnel after 6 hours and the farthest particle reaches the tunnel after 9 hours, similarly to the case of the field trace test.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.51-57
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• 1987

The intent of this research is to acquire some basic informations about formulation of the viral pesticide, Hyphantria cunea nuclear polyhedrosis virus and its virulence under field condition. The nuclear polyhedrosis virus was formulated as wettable powder using spreader, sticker and U.V. protector. The formulated product and aqueous virus were diluted with water at the concentration of 1${\times}$106PIB/ml and sprayed on mulberry leaves in the field. The leaves were fed with 3rd instar larvae of H. cunea to determine the inactivation period of the viral pesticides. The aqueous virus was completely inactivated on 5th day after spray, while the formulated one showed a spare mortality to the larvae even on 20th day after spray. In field application test, The fromulated and aqueous virus were sprayed on individual mulberry tree and 3rd instar laevae of H. cunea were fed on the trees. The mortality of the larvae one day after spray of the formulated and aqueous virus were about 50% and 40%, respectively. The formulated virus exhibited a persistent virulence to the larvae up to 9th day after spray, which the mortality was approximately 30%. The residual virulence of the formulated and aqueous virus was extended up to 4th day and 2nd day after spray, respectively.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.270-274
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• 2013

The bumblebee, Bombus terrestris, has played an important role as one of the alternative pollinators since the outbreak of honeybee collapse disorder. Recently, pathogens and parasites such as viruses, bacteria and mites, which affect the life span and fecundity of their host, have been discovered in B. terristris. In order to detect the microsporidian pathogen, Nosema spp. in the field populations of B. terristris, we collected adults and isolated their genomic DNA for diagnostic PCR. The PCR primers specific for Nosema spp. were newly designed and applied to gene amplification for cloning. Only small subunit ribosomal RNA (SSU rRNA) gene of N. ceranae was successfully amplified among examined genes and sequenced, which indicates that N. ceranae mainly infects the examined field population of B. terristris. To detect of SSU rRNA gene, two regions of SSU rRNA gene were selected by primary PCR analysis and further analyzed in quantitative real-time PCR (qRT-PCR). The qRT-PCR analysis demonstrated that SSU rRNA of N. ceranae was detected at concentration as low as $0.85ng/{\mu}l$ genomic DNA. This result suggests that the detection via qRT-PCR can be applied for the rapid and sensitive diagnosis of N. ceranae infection in the field population as well as risk assessment of B. terristris.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.371-373
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• 2006

Life history of Ivela auripes (Lepidoptera: Lymantriidae), a pest of Cornus controversa, was investigated both in laboratory and field condition. At $24{\pm}1^{\circ}C$, developmental period from larvae to adult and adult life span was $26.3{\pm}0.3$ and $4.4{\pm}0.2$ days, respectively. Developmental period of pupae reared in the laboratory was not significantly different from those collected in the field. Female moths reared in the laboratory laid significantly less eggs than those emerged from the pupae collected in the field. Light trap catches was less effective than direct monitoring in the field. The two monitoring results showed that adult moth emerged from early June to late June, and the time of 50% cumulative emergence was 17 June.

• Journal of the Korean Wood Science and Technology
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• v.40 no.6
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• pp.370-377
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• 2012

This study was conducted to investigate the color change of heat-treated wood made of Korean pine (Pinus koraiensis S. et Z.), and lodgepole pine (Pinus contorta Dougl). The wood samples were heat-treated at 9 different treatment combinations of temperature (170, 180, 200, 220, and $230^{\circ}C$), and time (90, 120, 180, 240, 270 min.) set up by a response surface method. Wood color was measured using a colorimeter, and the samples were installed for evaluating the resistance of termite in the field test sites set up in Jinju. The lightness decreased with the increase of treatment temperature and treatment time. The color differences were evaluated by the method of National Bureau of Standards (NBS), and response surface models to predict the color change were fitted as a function of treatment temperature and treatment time. The $R^2$ values of the fitted models of heat-treated Korean pine and lodgepole pines were 0.92, and 0.88, respectively, showing the potential way for the prediction of color changes. Severe damage was found from the samples in the field test site, which means that the manufactured heat-treated wood did not show the termite resistance enough for the outdoor use.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.2
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• pp.203-215
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• 2008

Film-induced tourism in Gyeongbuk and Korea is concentrated on the on-location set, one-off events and film tourism as part of a holiday(visiting film locations or studios as an activity within a larger holiday) among several forms of film-induced tourism. Film-induced tourism in Gyeongbuk has been increased since the opening of the KBS on-location set of Mungyeong. The on-location set has brought the growth of film-induced tourism and thus many local governments have competed with one another for the construction of the on-location set without considering the management of the on-location set. This study is aimed at suggesting ways to minimize these negative problems and to boost film-induced tourism. First of all, we should find ways to sustain each characteristic of the on-location set. Second, we should develop the new tourism destinations by diversifying the forms of film-induced tourism through the opening of the film-related events and the construction of the film-related facilities. Last, film-induced tourism should be enlarged to contents tourism. It needs to enlarge the role of the Gyeongbuk Film Commission. The Gyeongbuk Film Commission should take exclusive responsibility of developing the film-related tourism commodities.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.711-723
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• 2021

During the COVID-19 pandemic, social distancing affected daily life and leisure activities, including forest recreational activities. This study identified changes in people's participation in forest recreational activities and factors affecting their participation. It collected data from 1,000 samples through an online survey and analyzed it using a binary logit model with interaction terms. It was observed that there were decreases in the participation in visits to urban parks and green areas, outdoor activities in forests and mountains, and trips to mountain villages after the COVID-19 outbreak. People in their 40s, 50s, and 60s were more likely to decrease their participation in all kinds of forest recreational activities than those in their 20s. Moreover, higher household income earners were more likely to decrease their involvement in outdoor activities in forests and mountains. With respect to the place of residence, the residents in the Seoul metropolitan area were less likely to decrease their participation in trips to mountain villages than those outside this area. Thus, this study suggests that online forest recreation information services and forest management are needed to meet the demands of forest recreation for young generations and diversify the function of forests and rural areas as a safe leisurely space.