• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.05a
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• pp.121-121
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• 2002

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2007.04a
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• pp.176-177
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• 2007

We determined how presence of heterospecific individuals in the vicinity of a focal individual affects the behavior of two critically endangered species of cranes on their wintering grounds at Cheolwon in the Korean Demilitarized Zone(DMZ). The Red-crowned crane, Grus japonensis, is larger than the White-naped crane, Grus vipio, and it dominates the White-naped crane in aggressive interactions. We showed that the dominant species increases foraging activity in the presence of the subordinate species presumably because of scrounging of the food from the subordinate. Because interspecific interactions may affect avian endangerments this behavioral findings should be taken into account when managing winter refuges for the two engendered crane species.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.428-435
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• 2016

The objective of this study was to clarify the most effective component of grazing for improving welfare of fattening pigs. This study compared welfare indicators of 20 fattening pigs aged 100 to 124 days (the prior period) and 138 to 164 days (the latter period) in an indoor housing system (IS), an outdoor pasturing system (OP), a concrete floor paddock system (CF), a concrete floor paddock system with fresh grass (FG), or a soil floor paddock system (SF). The last three treatments include important components of a grazing system: extra space, grass feed, and soil floor. Behavior, wounds on the body, and performances, measured as average daily gain (ADG) and feed conversion ratio, were observed. CF pigs behaved similarly to IS pigs. FG pigs showed higher levels of foraging, chewing and activity. SF pigs engaged in higher levels of foraging, exploring, activity, and rooting, and showed a similar amount of playing behavior as OP pigs. ADG was the same in all treatments at the prior period, and increased in the order FG, IS, CF, SF, and OP at the latter. The behaviors and performance of SF pigs resembled those of OP which seemed to indicate a consistently higher standard of welfare than the other treatments. In conclusion, the existence of a soil floor is the most important component of a pasture for improving the welfare of pigs.

• Journal of Environmental Science International
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• v.24 no.3
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• pp.353-358
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• 2015

In this study, we analyzed two types of echolocation calls used by the parti-coloured bat, Vespertilio sinensis. Bats were captured in the Naejangsan National Park in October 2013. Call sounds of hand-released bats were recorded at the location of capture within the National Park. We analyzed pulse duration (PD), pulse interval (PI), peak frequency (PF), maximum frequency ($F_{MAX}$), minimum frequency ($F_{MIN}$), and bandwidth (BW). V. sinensis emitted the different types of the echolocation calls depending on the surrounding environment. Frequency modulated-constant frequency (FM-CF) signal of audible range was emitted when they flew in the uncluttered space over the canopy. However, when flying in the cluttered space below the canopy, they only emitted FM signal. FM-CF signal is in the audible range (e.g., low frequency), and FM signal has a harmonic broadband frequency range of two. There were significant differences in PD, PI, PF, FMAX, FMIN, and BW between the calls emitted over and below the canopy. Considering the functional characteristics of FM and CF signals, we conclude that the foraging activity of V. sinensis was observed below the canopy, and recommend the use of FM signal and broadband as echolocation signals.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.1
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• pp.189-210
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• 2011

This study aims to explore how users are tagging in order to utilize a folksonomy and whether they understand the social and interactive aspects of tagging in three different folksonomic systems, Connotea (www.connotea.org), Delicious(http://delicious.com), and CiteULike(www.citeulike.org). The study uses internet questionnaires, qualitative diary studies, and follow-up interviews to understand twelve participants' tagging activities associated with folksonomic interactions. The flow charts developed from the twelve participants showed that tagging was a quite complex process, in which each tagging activity was interconnected, and a variety of folksonomic system features were employed. Three main tagging activities involved in the tagging processes have been identified: item selection, tag assignment, and tag searching and discovery. During the tag assignment, participants would describe their tagging motivations related to various types of tags. Their perception of the usefulness of types of tags was different when their purpose was for social sharing rather than personal information management. While tagging, participants recognized the social potential of a folksonomic system and used interactive aspects of tagging via various features of the folksonomic system. It is hoped that this empirical study will provide insight into theoretical and practical issues regarding users' perceptions and use of folksonomy in accessing, sharing, and navigating internet resources.

• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.514-534
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• 2021

To estimate the territorial size of Reticulitermes speratus, a species of subterranean termites that damages wooden structures in Korea, appropriate dye markers were selected and the diffusion tendency was analyzed. According to the results of the sensitivity assessment using sawdust diet, increase in dye concentration reduced the amount of feed consumption but the dyeing becomes more intense. Except for the Neutral Red 0.5% group, all other concentration groups, including the control group, showed a survival rate of > 85% until week 4. For both, Nile Blue A and Neutral Red dye markers, all concentration conditions > 0.2%, except for the 0.1% concentration, were maintained for 11 weeks, and no sign of transfer effect was found except when the termites were fed with the dye markers. Therefore, it appears that 0.2% of Nile Blue A and Neutral Red is the optimal concentration for monitoring the R. speratus colonies. Additionally, we prepared an indoor 40 m long foraging arena consisting of a colony of 25,000 termites and released individuals stained with 0.2% of Nile Blue A and Neutral Red at both ends to assess the diffusion trends over time. The results showed that it took approximately 7 days for each dyed individual to gradually cover the 40 m distance and mix with each other. These findings reveal that when mark-release-recapture monitoring is conducted on the R. speratus colonies damaging wooden structures, the extent of the colony's activity area could be measured and different colonies could be distinguished from each other.

• Korean Journal of Environmental Biology
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• v.27 no.4
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• pp.375-383
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• 2009

The aims of this study were wintering individuals, usage of foraging sites, potential food availability, daily activity and disturbance factors of White-naped Cranes Grus vipio on the wintering site, Han-river estuary, Goyang and Gimpo city, Korea. We want to provide basic data to conserve the cranes. Maxium population was identified 162 individuals at the middle of February in the river side and mud flat of this study area. Spring migration for breeding was started at the first week of March and finished for two weeks later. White-naped Cranes were used four feeding sites in winter; agricultural area in Hongdopyong, Yihwa-dong, Pyong-dong and Songpo-dong. Expected carrying capacity (ECC) was 334 days (121~909 days). White-naped Cranes departed from roosting site to feeding site at every morning for foraging. If they were disturbed by some factors at feeding sites, they moved to mud flat in the Han river to forage and take a rest. Daily activity was consisted of six category; feeding, alert, locomotion, preening, comfort, social and other behaviors. Feeding was the highest portion among behaviors in the wintering area. Feeding, alert, locomotion and preening in daily activities significantly differed among feeding sites. We watched total 348 times of disturbances in the wintering sites. Artificial disturbances were vehicles, humans, bicycles and motorcycles. Natural disturbances were noises, animals and others. Disturbances in all wintering sites were highest in Yihwa-dong (134 times) and followed by Hongdopyong (109 times), Songpo-dong (64 times) and then Pyong-dong (44 times). And artificial disturbances (228 times) were more than natural disturbances (120 times). Especially, vehicle was one of the most checked factor in the wintering area.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.217-220
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• 2006

It is known that the process of variety development and maintenance of original plant is difficult in Angelica gigas and Angelica acutiloba because they are allogamous plants. The contents like this are stand in the way of theirs breeding. This study was conducted to investigate the foraging activity and pollinational efficacy by insects to flowers of A. gigas and A. acutiloba. Foraging activity by pollinators was observed every day from 10:00 to 10:30 during 3 days after September 21. Honey bee and fly were major pollinators. The rate of hymenoptera and diptera to total numbers of insects was the 56.5% and 40.6% in A. gigas, respectively. It was also 46.3% and 51.8% in A. acutiloba, respectively. The other insects were lepidoptera, coleoptera and hemiptera. The numbers of hymenoptera and diptera were more in flowers of A. gigas was 49.2% with bee, 36.0% with fly, 15.3% with human, 0.9% without anything in the nethouse and 76.6% in the open field. That of A. acutiloba was 43.6% with bee, 27.9% with fly, 20.3% with human, 0.6% without anything in the nethouse and 46.9% in the open field. Excepting open field, seed setting rate of with bee in the nethouse was the highest of all the others. However, we concluded that the use of fly was the most effective method for pollination of A. gigas and A. acutiloba considering low cost and convenient handling.

• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.159-167
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• 2017

Historical wooden buildings in Korea are being damaged by Reticulitermes speratus kyushuensis Morimoto, a type of subterranean termite, and the scale of this damage is increasing gradually because of global warming. This study evaluated the ingestion toxicity of the phenylpyrazole insecticide fipronil to R. s. kyushuensis and its applicability as termite bait with the aim of controlling termite colonies more efficiently. An ingestion toxicity assessment was conducted and the $LT_{50}$ was determined to be 4.43 day at concentrations of 10 ppm, indicating a slow-acting effect; therefore, 10 ppm was selected as an appropriate dose. A field applicability assessment was conducted in which the number of foraging workers and the rate at which the termites fed decreased 2 weeks after baiting, and termite colony activity was no longer apparent after 4 weeks demonstrating the efficacy of fipronil at eliminating colonies. Taken together, these results, indicate that low-dose fipronil eliminated R. s. kyushuensis colonies faster than insect growth regulators; therefore, it is expected to be useful when trying to conserve historical wooden buildings.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.681-692
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• 2015

It is well documented that physiological and nutritional condition of wintering birds is strongly related to migration success to breeding sites, and also breeding success. However, how abiotic factors during winter affect the migration and breeding successes still remains unclear. Thus, this study developed a dynamic-state-dependent model for wintering life-history to identify the potential impact on the life-history, success to breeding site and breeding success of wintering birds, which are related to temperature fluctuation, interspecific competition and human disturbance at the wintering sites. To find the best-fit-model, we referred to the existing research data on wintering ecology of Red-crowned cranes (Grus japonensis) in Cheolwon, Korea, which is well documented as a long-term wintering study. Our model predicted that the higher temperature fluctuation and a higher rate of human disturbance are negatively related to migration success to breeding sites and their fitness, ultimately breeding success via changing of proportion in resource allocation (for e. g., lower energy compensation or higher level of stress accumulation). Particularly, the rate of body mass compensation after arrival at wintering sites may be accelerated when there are less temperature fluctuations and a lower rate of human disturbance. In addition, the rate of interspecific competition sharing the wintering foraging sites is negatively related to the rate of body mass compensation. Consequently, we discussed the conservation strategies of wintering birds based on the outcomes of the model.