• Korean Journal of Agricultural Science
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• v.50 no.3
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• pp.507-512
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• 2023

The traditional oviposition ground for indoor breeding of Luciola lateralis is moss. This study was conducted to find the most suitable alternative oviposition ground that can maintain or increase the oviposition rate of L. lateralis while addressing the problems of larva collection time and larva loss that occur when moss is used. As alternative candidate oviposition ground comprising six colors of non-woven fabric and felt were used to measure the fecundity variation rate of L. lateralis with respect to the color and material of the oviposition ground. In addition, measure the fecundity variation rate of L. lateralis in moss, a traditional oviposition ground, was also measured and investigated for comparison. The investigation showed that the average number of eggs in the non-woven fabric group was higher than that in the felt group. The yellow non-woven fabric had an average number of eggs that was more than 100 times higher than of moss used as a traditional oviposition ground. In the space where the six color non-woven fabric were together, L. lateralis concentrated its oviposition on yellow. These results showed that yellow non-woven fabric can be sufficiently used for efficient indoor mass breeding of L. lateralis while addressing problems caused by moss, a traditional oviposition ground.

• Journal of Animal Environmental Science
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• v.15 no.1
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• pp.1-8
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• 2009

This study was conducted to analyze the effects of sow breeding environment on the reproduction in the first litter in a large-sized hog farm, located in Dangjin-gun, Chungnam from July 1st, 2007 to June 30th, 2008 and provide basic information to improve the sow productivity in a family farming sows. The results obtained were as follows; 1. The gestation periods were proved to be similar without significant differences between indoor and outdoor breeding grounds, The average of farrowing rate was 91.91%, and 92.54% farrowing rate of out-door ground breeding sows was slightly greater than 91.57% of group-housed sows, but there was no significance between two groups. 2. The average of total litter size and the number of born alive per litter were 9.81 and 9.02, respectively. The number of total number was 0.98 and the number of born alive per litter was 1.18 in the outdoor-ground breeding sows, which was significantly greater than group-housed sows(p<0.001). 3. The number(rate) of piglets stillborn was 0.22(2.10%) from the outdoor-ground breeding sows was significantly greater, compared with 0.33(3.53%) from group-housed sows(p<0.01). The number of piglets culled was 0.23(2.27%) and 0.26(2.77%), in the out-door ground breeding sows and in group-housed sows, respectively and it was not significantly similar between two groups. And, the number of mummies was 0.21(2.1%) and 0.28(2.29%), in the out-door ground breeding sows and in group-housed sows, respectively, which showed no significance. 4. The weaning number in the playground breeding sows was 9.48 and it was significantly greater than that in the group-housed sows(p<0.001). The average of weaned age was observed to be 22.91 days. The weaned age in the out-door ground breeding sows was 22.39 days, and it was significantly smaller than that in group-housed sows(p<0.001). The breeding rate for the weaning of pigs was satisfactory as 96.82%, but there was no significant difference between two groups.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.39-44
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• 2000

This study was carried out to obtain the basic information about the sucker producing characteristics of certain burley tobacco varieties(Nicotiana tabacum L. var. burley) at Suwon and Chonju Experiment Station, Korea Ginseng & Tobacco Research Institute in 1999. The number and weight of suckers for 12 varieties or breeding lines were investigated three times, 45 days after transplanting for ground sucker, 10 days after topping, and 10 days after maleic hydrazide(MH) applying for upstalk sucker. KB 103 and KB 9416-1 produced less ground suckers and upstalk suckers than other entries did. KB 9210-8 produced less ground suckers and (Male sterile TC 612 x KB 108)F$_1$ also produced less upstalk suckers than other entries did. There was no differences among entries in sucker production at 10 days after MH treatment. Between the weight of total sucker and days to flower revealed the negative correlation, but not significant. The low sucker producing entries described above could be used as a parental line in the breeding program for the low sucker producing variety.

• Korean Journal of Ornithology
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• v.25 no.2
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• pp.101-105
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• 2018

On 22 June 2018, we observed the breeding of the Pied avocet (Recurvirostra avosetta) at landfill sites in Saemangeum, Jeollabuk-do Province. The breeding ground was a temporary swamp, and four juvenile were constantly observed with adult bird. This observation is the first breeding record of Pied avocet (Recurvirostra avosetta) in Korea.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.737-742
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• 2013

The purpose of this study was to remove sediments obtained from breeding ground using supersonics and micro-air flotation method. Sediments from Tongyong breeding grounds showed no contaminations of heavy metals but had great amount of organics. Thus, efficient removal of sediments was required to preserve water quality near breeding ground. Supersonics treatment for sediments was determined to be essential because higher removal efficiency of sediments was obtained when supersonics treatment was used. In addition, application of coagulants increased removal efficiency because its usage increased particle size of sediments, which enabled easy trapping of sediments particle into micro-air bubbles. Removal efficiency of sediments slightly decreased from 95.8% (1 g/L) to 83.9% (8 g/L) at the tests for different amount of sediments, but most of tiny particles were removed from water where sand size particles were left in the bottom of reactors.

• Korean Journal of Environmental Biology
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• v.28 no.2
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• pp.49-55
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• 2010

There are only 10,000 Saunders' Gull's (Larus saundersi Swinhoe) surviving in the world today. But they are being threatened by coastal habitat, degradation, development pressure and disturbance by humans. Their first breeding record in Korea was in 1998 and the breeding status has been studied, however, the breeding status is not sufficient for this species. This study was performed from May 1999 to June 2009 to clarify breeding populations and trend of the Saunders' Gull population in Korea. The results indicate that the breeding population has been increasing gradually from 300 to 1,300 individuals, though disturbance increased. As threats to the breeding birds, physical environmental factors such as development and human disturbance were identified as a major threatening factors. Also, as a secondary factor, eggs and chicks are falling pray to predators. Incheon bay breeding places have been created by a landfill projects for the purpose of urban and industrial development, thus, these places will no longer be available for this species. In addition, the breeding habitat has been reduced and changed by expansions of development on the ground. Therefore, well planed management schemes should be provided for the species' breeding population to be continually breed and survive.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.13-13
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• 2017

By the progress of genome sequencing, infrastructures for marker-assisted breeding (MAB) of rice came to be established. Fine mapping and gene isolation have been conducted using the breeding materials derived from natural variations and artificial mutants. Such genetic analysis by the genome-wide dense markers provided us the knowledge about the many genes controlling important traits. We identified several genes or quantitative trait loci (QTL) for heading date, blast resistance, eating quality, high-temperature stress tolerance, and so on. NILs of each gene controlling heading date contribute to elongate the rice harvest period. Determination of precise gene location of blast resistance gene pi21, allowed us to overcome linkage drag, co-introduction of undesirable eating quality. We could also breed the first practical rice cultivar in Japan with a brown planthopper resistance gene bph11 in the genetic back-ground of an elite cultivar. Discovery of major and minor QTLs for good eating quality allowed us to fine-tune of eating quality according to the rice planting area or usage of rice grain. Many rice cultivars have bred efficiently by MAB for several traits, or by marker-assisted backcross breeding through chromosome segment substitution lines (CSSLs) using genetically diverse accessions. We are also systematically supporting the crop breeding of other sectors by MAB or by providing resources such as CSSLs. It is possible to pyramid many genes for important traits by using MAB, but is still difficult to improve the yielding ability. We are performing a Genomic Selection (GS) for improvement of rice biomass and grain yield. We are also trying to apply the genome editing technology for high yield rice breeding.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.333-343
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• 2015

This research aims at identifying the goshawk's possible and replaceable breeding ground by using the MaxEnt prediction model which has so far been insufficiently used in Korea, and providing evidence to expand possible protection areas for the goshawk's breeding for the future. The field research identified 10 goshawk's nests, and 23 appearance points confirmed during the 3rd round of environmental research were used for analysis. 4 geomorphic, 3 environmental, 7 distance, and 9 weather factors were used as model variables. The final environmental variables were selected through non-parametric verification between appearance and non-appearance coordinates identified by random sampling. The final predictive model (MaxEnt) was structured using 10 factors related to breeding ground and 7 factors related to appearance area selected by statistics verification. According to the results of the study, the factor that affected breeding point structure model the most was temperature seasonality, followed by distance from mixforest, density-class on the forest map and relief energy. The factor that affected appearance point structure model the most was temperature seasonality, followed by distance from rivers and ponds, distance from agricultural land and gradient. The nature of the goshawk's breeding environment and habit to breed inside forests were reflected in this modeling that targets breeding points. The northern central area which is about $189.5 km^2$(2.55 %) is expected to be suitable breeding ground. Large cities such as Cheongju and Chungju are located in the southern part of Chungcheongbuk-do whereas the northern part of Chungcheongbuk-do has evenly distributed forests and farmlands, which helps goshawks have a scope of influence and food source to breed. Appearance point modeling predicted an area of $3,071 km^2$(41.38 %) showing a wider ranging habitat than that of the breeding point modeling due to some limitations such as limited moving observation and non-consideration of seasonal changes. When targeting the breeding points, a specific predictive area can be deduced but it is difficult to check the points of nests and it is impossible to reflect the goshawk's behavioral area. On the other hand, when targeting appearance points, a wider ranging area can be covered but it is less accurate compared to predictive breeding point since simple movements and constant use status are not reflected. However, with these results, the goshawk's habitat can be predicted with reasonable accuracy. In particular, it is necessary to apply precise predictive breeding area data based on habitat modeling results when enforcing an environmental evaluation or establishing a development plan.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.2
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• pp.85-92
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• 2022

The amphibian breeding habitat is confirmed by mating call. In some cases, the researcher directly identifies the amphibian individual, but in order to designate the habitat, it is necessary to map the mating call region of the amphibian population. Until now, it has been a popular methodology for researchers to hear mating calls and outline their breeding habitats. To improve this subjective methodology, we developed a technique for mapping mating call regions using Unmanned Aerial Vehicle (UAV). The technology uses a UAV, fitted with a sound recorder to record ground mating calls as it flies over an amphibian habitat. The core technology is to synchronize the recorded sound pressure with the flight log of the UAV and predict the sound pressure in a two-dimensional plane with probability density. For a demonstration study of this technology, artificial mating call was generated by a potable speaker on the ground and recorded by a UAV. Then, the recorded sound data was processed with an algorithm developed by us to map mating calls. As a result of the study, the correlation coefficient between the artificial mating call on the ground and the mating call map measured by the UAV was R=0.77. This correlation coefficient proves that our UAV recording system is sufficiently capable of detecting amphibian mating call regions.

• 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.