• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.150-164
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• 2022

The objective of this study is to analyze the biodiversity changes and characteristics of the benthic macroinvertebrate community in the Nakdong River with eight weirs, which was constructed as one of the Four Major River Restoration Projects from May to October 2020. The study also includes the analysis of changes in the major groups of benthic macroinvertebrates for about ten years, from 2010 to 2020. The surveys collected 97 species of benthic macroinvertebrates belonging to 83 genera, 52 families, 18 orders, five classes, three phyla, and 128.1 individuals/m². Chironomidae sp. and Tubificidae spp., which are pollutant indicators, dominated throughout the sections. The community analysis result shows the average dominant index and the diversity index of 0.62±0.20 and 1.87±0.63, respectively, and indicated the most stability of the freshwater ecosystem in the upper stream of the Nakdong River. The survey showed dominance by Chironomidae sp. at the center of the Nakdong River weir and the most unstable community in Chilgok and Gangjeong Goryeong weirs. The results of the community stability analysis showed a high distribution of the characteristic group I with high resilience and resistance and small distribution of characteristic group III with low resistance and resilience, indicating a very unstable condition of communities in the Nakdong River weir section. Predators were relatively abundant among the functional feeding groups (FFGs), whereas shredders, gathering-collectors, and filtering-collectors were relatively lower. Among the habitat orientation groups (HOGs), burrowers and climbers were dominant, indicating a wide distribution of groups in ecosystems with low dissolved oxygen. An endangered species level II of Macromia daimoji was found in Sangju and Nakdan weirs. The analysis results for 10 years from 2010 showed that the number of species and populations increased immediately after the dam construction but plummeted in 2016 and are now stabilizing. Chironomidae spp. has been dominant in all sections over the past 10 years, and they are currently maintained at a rate of about 50%. The EPT groups have decreased significantly since 2011, and the Plecoptera and Trichoptera of the group have not yet been restored. The population of Tubificidae spp. showed an increase after construction was completed in 2012 and drastically increased in 2015 and 2020. The species of Cristaria plicata, designated as endangered species level I, has not been observed since 2011 in Hapcheon Changnyeong weir. Moreover, Macromia daimoji was rarely observed in seven weirs until 2015, and it has been confirmed that the current distribution habitat has decreased rapidly.

• Korean Journal of Environment and Ecology
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• v.37 no.4
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• pp.289-301
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• 2023

Forests within watersheds are essential in maintaining ecosystems and are the central infrastructure for constructing an ecological network system. However, due to indiscriminate development projects carried out over past decades, forest fragmentation and land use changes have accelerated, and their original functions have been lost. Since a forest's structural pattern directly impacts ecological processes and functions in understanding forest ecosystems, identifying and analyzing change patterns is essential. Therefore, this study analyzed structural changes in the forest landscape according to the time-series land cover changes using the FRAGSTATS model for the dam watershed of the Geum River upstream. Land cover changes in the dam watershed of the Geum River upstream through land cover change detection showed an increase of 33.12 square kilometers (0.62%) of forests and 67.26 square kilometers (1.26%) of urbanized dry areas and a decrease of 148.25 square kilometers (2.79%) in agricultural areas from the 1980s to the 2010s. The results of no-sampling forest landscape analysis within the watershed indicated landscape percentage (PLAND), area-weighted proximity index (CONTIG_AM), average central area (CORE_MN), and adjacency index (PLADJ) increased, and the number of patches (NP), landscape shape index (LSI), and cohesion index (COHESION) decreased. Identification of structural change patterns through a moving window analysis showed the forest landscape in Sangju City, Gyeongsangbuk Province, Boeun County in Chungcheongbuk Province, and Jinan Province in Jeollabuk Province was relatively well preserved, but fragmentation was ongoing at the border between Okcheon County in Chungcheongbuk Province, Yeongdong and Geumsan Counties in Chungcheongnam Province, and the forest landscape in areas adjacent to Muju and Jangsu Counties in Jeollabuk Province. The results indicate that it is necessary to establish afforestation projects for fragmented areas when preparing a future regional forest management strategy. This study derived areas where fragmentation of forest landscapes is expected and the results may be used as basic data for assessing the health of watershed forests and establishing management plans.

• (The) Research of the performance art and culture
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• no.41
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• pp.257-284
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• 2020

Goseong Ogwangdae started academic research in the late 1950s and was designated as a national intangible cultural asset in 1964. From the time of the academic survey to the time of designation, it was recorded as using paper masks, but when the recording image was filmed in 1965, it was already changed to wooden masks. In 1960, before being designated as an intangible cultural asset, the number of masks, which was 9 points, gradually increased to 19 points in 1964. It is necessarily included in the leper, Chorani, Malttuki, Cheongbo-Yangyang, Halmi, and Jemilju, but the character of the yangban is not yet clearly differentiated. Hwangbongsa and Sangju appeared as bare faces, and consumption, milling, Cheongbo-Yangyang are used together with Bibi and inspiration. It can be guessed that Bibi was not the appearance of a foreign object with horns as it is now, considering that Bibi and Madangsoi were used together. Since 1965, shortly after the designation, the whole of the Goseong Ogwangdae mask has been changed to a wooden mask. All the characters except for resident, courtyard, and top-of-the-line are wearing masks. Bibi, Hongbaek, and service masks have never appeared until 1964. The Yangban was changed to the closing ceremony with six people in the order of Won-Yangban, Baekje, Heukje, Cheongje, Hongbaek, and Jonggadoryong. Starting in 1969, the mask enters the stable period where the kind is the same as the present. Bibi-Yangban uses both the Won-Yangban and the Jemilju uses the Somu, but all other characters use the individual mask to use a total of 18 masks. The Yangbans are clearly differentiated, and a total of seven Yangban appear. The reason why the change in the type of mask and the expression of material is so large is that the first generation of mask makers died and the tradition of mask production was cut off, but there is also a cause of the extreme change in the environment of the drama that the performers who joined after the designation had to face. Also, it is closely related to the change of the times when the meaning and weight of masking in masking has changed. At that time, the performers were not so tied to the current concept of 'original form' that they preserved the appearance of the designated time. Originally, Goseong Ogwangdae was centered on improvisation dance, not the formalized dance as it is now, and there was a certain fluid aspect in the retelling, so it was flexible in the use of masks even before the designation of cultural assets. Strict rules did not apply in the details, as it was a self-sufficient play by the performers, not an offer event. The form and contents of this fluid play are changed to preparation for the performance while preparing for the folk art contest. As the subject of the contest in self-sufficient play, dance, costumes, and props became more and more colorful as well as dancing, costumes, and props. As a result, participation in the contest brought about changes in the overall performance and changed the mask, which was accepted within the preservation society.

• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.1-18
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• 1986

This study was initiated to estimate productivity of Quercus variabilis stand. However the practical objective of this study was to provide some information to establish the basis of selecting the suitable site for Quercus variabilis. The productivity measured in terms of DBH, height, basal area and stem volume was hypothesized, respectively, to be a function of a group of factors. This study considered 32 factors, 20 of which were related to the forest environmental factors such as tree age, latitude, percent slope, etc. and the rest of which were related to soil factors such as soil moisture, total nitrogen, available $P_2O_5$, etc. The data on 4 productivity measurements of Quercus variabilis growth and related factors cited were collected from 99 sample plots in Kyeongbook and chungbook provinces. Some factors considered were, in nature, discrete variables and the others continuous variables. Each kind of factor was classified into 3 or 4 categories and total numbers of such categories were eventually amounted to 110. Then each category was treated as an independent variable. This is amounted to saying that individual variable was treated a dummy variable and assigned a value 1 or 0. However the first category of each factor was deleted from the normal equation for statistical consideration. First of all, each of 4 productivity measurements of Quercus variabilis growth was regressed and, at the same time, those 110 categories. Secondly, the partial correlation coefficients were measured between each pair of 4 productivity measurements and 32 individual foctors. Finally, the relative scores were estimated in order to derive the category ranges. The result of these statistical analyses could be summarized as follows: 1) Growth measurement in terms of height seems to be a more significant criterion for estimation of productivity of Quercus variabilis. 2) Productivity of forest on stocked land may better be estimated in terms of forest environmental factors, on the other hand, that of unstocked land may be estimated in terms of physio-chemical factors of soil. 3) The factors that a strongly positive relation to all growth factors of tree are age group, effective soil, soil moisture, etc. This implies that these factors might effectively be used for criteria for selecting the suitable site for Quercus variabilis. 4) Parent rock, latitude, total nitrogen, age group, effective soil depth, soil moisture, organic matter, etc., had more significant category range for tree growth. Therefore, the suitable site for Quercus variabilis may be selected, based on this information. In conclusion, the above results obtained by the multivariable analysis can be not only the important criteria for estimating the growth of Quercus variabilis but also the useful guidance for selecting the suitable sites and performing the rational of Quercus variabilis forest.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.373-386
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• 2004

This study was conducted to investigate effects of the brown seaweed residues supplementation on in vitro fermentation, and milk yield and milk composition of dairy cows. Therefore, two experiments consisting of an in vitro and an in vivo growth trial were used. In in vitro experiment, brown seaweed residues(BSR) was supplemented in basal diet with 0, 1, 2 and 4% respectively, and incubated for 3, 6, 9, 12, and 24 h. The pH value, ammonia-N and VFA were investigated. The pH value tended to increase with increasing BSR during the incubation. Particularly, pH was significantly higher in BSR treatments compared with control at 9 h(p < 0.05). While, ammonia-N concentration was not significantly different across treatments during the whole incubation. BSR supplementation did not affect total VFA production, but acetate was linearly increased in BSR treatments compared with control at 12 h(p < 0.05), and its concentration was highest(92.70 mM) in 4% BSR among treatments. The concentration of iso-butyrate tended to increase in BSR treatments in comparison to control during the incubation. In addition, the concentration of iso-valerate was higher in BSR treatments compared with control at 12 and 24 h. In growth trial, BSR was added(800 g/d/animaI) to diets of dairy cow. Dry matter intake was not affected by BSR supplementation, but daily milk yield(kg) significantly increased in BSR treatment compared with control(p < 0.05). However, milk composition(%) and milk yield(kg) were not significantly different between treatments. Milk fat(% and kg/d) tended to slightly decrease in BSR treatment compared with control(3.59% and 1.06 kg/d vs. 3.32% and 1.01 kg/d), The contents of C16:0 and C20:4 in milk significantly increased in BSR treatment compared with control reflecting from dietary fatty acid composition. The content of C18:0 in milk which is end product of biohydrogenation of CI8 unsaturated fatty acids in the rumen significantly increased in BSR treatment compared with control(p < 0.05). C18:2 content in milk tended to decrease, but tended to increase trans-II C18:l and CLA contents in milk in BSR treatment compared with control. In conclusion, it could be summarized that BSR may stabilize rumen pH, and it could improve milk yield and CIA content in milk with more than 4% of diet. Therefore, BSR could be beneficially used in dairy diets as a feed additive.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.21-30
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• 2005

Feeding behavior of foraging ants including visiting numbers, species, and preference on insect cadavers killed by entomopathogenic nematodes <(Heterorhabditis sp. KCTC 0991BP (He) and Steinernema carpocapsae KCTC 0981BP (Sc)> and their symbiotic bacteria was investigated in Dongrae Benest Golf Club, Anyang Benest Golf Club, Gapyung Benest Golf Club and Ulsan Golf Club. The number of ants, kinds and numbers of cadavers taken away by ants were different depending on killing method, golf club and site within the golf courses (fairway and rough). The feeding preference of ants was the lowest on cadavers killed by He. At Dongrae Benest Golf Club Lasius japonicu ($75{\pm}5\%$) and Monomorium floricola ($10\%$) took away cadavers only at the rough. The visiting rate of ants was $85{\pm}6\%$ at the rough, but none at the fairway by 16 hours. The taken rate of cadavers by ants was the lowest on He-killed cadavers representing $16.7\%$ compared with $40.0\%$ on Sc-killed cadavers, $53.3\%$ on fenitrithion-killed cadavers, and $56.7\%$ on natural dead cadavers by 12 hours. At the rough of hole 6 in Anyang Benest Golf Club, Tetramorium tsushimae ($33{\pm}12\%$), Pheidole fervida ($17{\pm}15\%$), Camponatus japonicus ($10\%$), Formica japonica ($7{\pm}6\%$), Paratrechina flavipes ($3{\pm}6\%$), and Crematogaster matsumurai ($3{\pm}6\%$) took away cadavers, but $23{\pm}15\%$ of cadavers were not visited by ants. Ants took away $40\%$ of Sc-killed cadavers, $16.7\%$ of frozen-killed cadavers, and $3.4\%$ of He-killed cadavers. The number of visiting ants was low at the hole 9 of Cherry course in Gapyung Benest Golf Club and only Tetramorium tsuhimae and Paratrechina flavipes were found from one site. The density of entomopathogenic nematodes did not influence ant visiting on cadavers, but burying affected ant visiting. Although ants took away unburied cadavers, buried cadavers were taken away at the hole 6 of Dongrae Benest Golf Club by 16 hours. Ant visiting had the same tendency on symbiotic bacterium-treated biscuit as nematode-killed cadavers. The visiting was less on biscuit inoculated by Photorhabdus sp., a symbiotic bacterium of He than on biscuit inoculated by Xenorhabdus nematophila, a symbiotic bacterium of Sc.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.383-391
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• 2007

This study was conducted for an assessment through the estimation of soil loss by each catchment classified by soil catena. Ten catchments, which are Geumgang21, Namgang03, Dongjincheon, Gapyongcheon01, Gyongancheon02, Geumgang16, Byongsungcheon01, Daesincheon, Bukcheon02, Youngsangang08, were selected from the hydrologic unit map and the detailed soil digital map (1:25,000) for this study. The catchments like Geumgang21, Namgang03, Dongjincheon, Gapyongcheon01 and Gyongancheon02 were mainly composed with soils originated from gneiss. The catchments like Geumgang16, Byongsungcheon01, Daesincheon, Bukcheon02 and Youngsangang08 were mainly composed with soils originated from granites. The grades, which are divided into seven grades with A(very tolerable), B(tolerable), C(moderate), D(low), E(high), F(severe), G(very severe), of soil erosion estimated by USLE in catchments were distributed in most A and B because of paddy land and forestry. In detailed, the soil erosion grade of catchments mainly distributing soils originated from gneiss showed more the distribution of B and C than it of catchments mainly distributing soils originated from granites. The reason of results would be derived from topographic characteristics of soils originated from gneiss located at mountainous. The soil loss according to soil catena linked with Songsan and Jigok series, which are soils originated from gneiss was calculated with $7.66ton\;ha^{-1}\;yr^{-1}$. The soil loss of Geumgang16, Byongsungcheon01, Daesincheon, Bukcheon02 which have the soil catena linked with Samgak and Sangju soil series originated from granite, was calculated with $5.55ton\;ha^{-1}\;yr^{-1}$. The soil loss of Youngsangang08 which have the soil catena linked with Songjung and Baeksan soil series originated from granite was calculated with $9.6ton\;ha^{-1}\;yr^{-1}$, but the conclusion on soil loss in this kind of soil catena would be drawn from the analysis of more catchments. In conclusion, the results of this study inform that the classification of soil catena by catchments and estimation of soil loss according to soil catena would be effective for analysis on the grade of non-point pollution by soil erosion in a catchment.