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A Review of Ecological Niche Theory from the Early 1900s to the Present (생태적 지위(Ecological Niche) 이론에 대한 검토 및 제언)

  • Koo, Kyung Ah;Park, Seon-Uk
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.316-335
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    • 2021
  • This study reviewed the change of theory of ecological niche(concepts and definitions) over time to provide a theoretical basis for habitat-related studies of animals and plants. Accordingly, it analyzed and summarized the major discussion trends of ecological niche worldwide in each period from the 1900s to the present. Countries advanced in ecological studies, such as the EU and the USA, have conducted theoretical and empirical studies on the ecological niche since the early 1990s. The concept of the ecological niche was introduced in the early 1900s, developed in the mid-1900s, and advanced from the mid-1900s to the late 1900s. Since the 2000s, the advanced concept has diversified with new developments in technologies and research methods. The factors suggested by theoretical and empirical studies in defining the ecological niche of a species include 1) population dynamics of the target species, 2) all biotic conditions to sustain a population (food relationship and material flow in the food chain), 3) all non-biotic conditions to sustain a population (physical environmental conditions), 4) all direct and indirect interactions between these environmental factors, and 5) response and adaptation mechanisms that include the migratory ability of the target species or genetic diversity and adaptability to change. Unlike such international advancement, there have not been sufficient theoretical, philosophical, and empirical studies of ecological niche in Korea. The concepts and definitions by Greennell, Elton, and Hutchinson were selectively and partially borrowed for empirical studies without full description. Considering that the theory of ecological niche becomes the foundation for habitat-based species conservation and restoration, it is necessary to seek diversification and advancement of theoretical and empirical research and research methods and technological development. It will provide an important foundation for the academic advancement of ecology and for establishing and implementing policies to preserve and restore ecology and biodiversity effectively and successfully in Korea.

Anti-Inflammatory Effect of Essential Oils Extracted from Wood of Four Coniferous Tree Species (침엽수 4종 목부 정유의 항염증 효과 평가)

  • YANG, Jiyoon;CHOI, Won-Sil;KIM, Jae-Woo;LEE, Sung-Suk;PARK, Mi-Jin
    • Journal of the Korean Wood Science and Technology
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    • v.47 no.6
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    • pp.674-691
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    • 2019
  • The aim of this study was to evaluate the anti-inflammatory effects of essential oils extracted from the wood of Chamaecyparis obtusa, Pinus densiflora, Pinus koraiensis, and Larix kaempferi. Essential oils were extracted by hydrodistillation, and their chemical components were determined by GC/MS. Major chemical components of these essential oils were ${\alpha}$-cadinol (19.25%), ${\tau}$-muurolol (14.20%), and ${\alpha}$-pinene (13.74%) in C. obtusa; ${\alpha}$-pinene (47.16%), longifolene (14.31%), ${\beta}$-phellandrene (11.78%), and ${\beta}$-pinene (11.02%) in P. densiflora; ${\alpha}$-pinene (13.49%) and longifolene (10.79%) in P. koraiensis, and geranyl linalool (23.58%) and ${\alpha}$-pinene (18.57%) in L. kaempferi. To evaluate the anti-inflammatory effects of essential oils, lipopolysaccharide (LPS)-induced RBL-2H3 mast cells were treated with these essential oils; then, the changes in the mRNA expression level of the cytokines IL-4 and IL-13 were examined. Further, degranulation was evaluated by measuring ${\beta}$-hexosaminidase release. After LPS-induced RBL-2H3 mast cells were exposed to $10^{-7}%$ of all types of essential oils, the gene expression levels of IL-4 and IL-13 within the cells remarkably decreased. The relative mRNA expression level of IL-4 was 69.6% in P. densiflora, 63.2% in P. koraiensis, 55.1% in C. obtusa, and 45.8% in L. kaempferi compared with that in the group treated with LPS. The mRNA expression level of L-13 should a similar trend. The inhibitory rate of IL-13 mRNA expression of P. densiflora, P. koraiensis, C. obtusa, and L. kaempferi was 57.8%, 57.1%, 51.1%, and 34.5%, respectively. ${\beta}$-Hexosaminidase release significantly decreased following the treatment with the four types of essential oils. The rate of ${\beta}$-hexosaminidase release were 38.1% C. obtusa; 33.0% P. densiflora; 27.4% P. koraiensis; and 9.1% L. kaempferi. Among all types of essential oils, that extracted from P. densiflora wood showed the highest anti-inflammatory activity. These results show that the tested essential oils exert an anti-inflammatory effect through the inhibition of degranulation and expression of cytokines.

Applying IUCN Regional/National Red List Criteria to the Red List (Vascular Plants) Published by the Ministry of Environment of Korea (환경부 적색목록(관속식물)에 대한 IUCN 지역적색목록 평가적용)

  • Chang, Chin-Sung;Kwon, Shin-Young;Son, Sungwon;Shin, Hyuntak;Kim, Hui
    • Journal of Korean Society of Forest Science
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    • v.109 no.4
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    • pp.371-381
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    • 2020
  • The Ministry of Environment (ME) is planning to adopt in 2020 the IUCN regional Red List for "Guidelines for listing and delisting rare & endangered species and management of endangered Species System". The ME designated 377 species of vascular plants on the regional Red List. In a previous study it had been suggested that 103 species from this list are candidates for the regional Red List. With respect to a possible Red List, we assessed 59 species (after excluding 34 additional NA species and ten endemic species). These assessments indicated that 16 species are at the "threatened" level. Of those, one species is Critically Endangered, ten are Endangered, and five are Vulnerable. A further four species are classified as Near Threatened, 30 as Of Least Concern, and nine as Data Deficient. We found that most of the assessments proposed by the Ministry of Environment were not supported by scientific data, including quantitative geographic data (over 70%) in Criteria B. In order to determine the endangered species belonging to the orchid family, it is necessary to obtain records of illegal activities or data on overcollection. The current problem with the Ministry of Environment Red List has been the lack of management of scientific data on species showing a trend in decreasing population in the mid- to long-term; thus, there is a lack of critical resources for policy-makers. The ME legally designated categories and assessment, and the lack of expertise in failing to comply with the legal law by itself. The key to presenting an accurate overview of the state of Korean flora is to fill the information gaps with respect to significant geographical and taxonomical biases in the quality and quantity of data. By regularly updating the qualified data, we will be able to track the changes in the conservation status of the flora and inform the necessary conservation policies.

Application of microwave water surface current meter for measuring agricultural water intake (농업용수 사용량 계측을 위한 전자파 표면유속계의 적용)

  • Baek, Jongseok;Kim, Chiyoung;Lee, Kisung;Kang, Hyunwoong;Song, Jaehyun
    • Journal of Korea Water Resources Association
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    • v.53 no.12
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    • pp.1071-1079
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    • 2020
  • For integrated water management, it is essential to secure basic data such as the amount of agricultural water intake. The river water intake through the intake weir is carried out through the agricultural irrigation canal, and a method for measuring the quantity of water intake is required to suit the characteristics of the measuring points. In this study, the accuracy of the calculated flow data was determined by applying a microwave water surface current meter. The microwave water surface current meter is a method of calculating surface velocity using doppler effect, which is mainly used in high-velocities situations such as flood. Surface velocity is difficult to represent the average velocity of the entire section at low dicharges or high wind speeds, it is considered to be low in continuous utilization throughout the year, and it is necessary to verify whether the measurement using an microwave water surface curren meter is appropriate in agricultural irrigation canal. The data measured with an microwave water surface curren meter were compared with the actual flow data to calculate the intake data in agricultural irrigation canal. In agricultural irrigation canal, the low-level discharge calculated using an microwave water surface current meter at a minimum velocity of about 0.3 m/s and a minimum discharge of about 1.0 m3/s or higher was found to have a high tendency and accuracy compared to the standard discharge, especially when the high discharge was high. Although effective results can be obtained in terms of quantity at low discharge, it is deemed that subsequent studies are needed to calculate the average discharge of the cross section at low discharge, given that the trend of data is unstable. Through this study, it is suggested that it is appropriate to calculate the amount of water intake through the microwave water surface current meter in artificial waterways with a certain discharge or higher, so it is expected to be widely distributed as a method for measuring river water intake.

Understanding the Impact of Environmental Changes on the Number of Species and Populations of Odonata after Creating a Constructed Wetland (인공습지 조성 후 환경변화가 잠자리목의 종수 및 개체수에 미치는 영향 파악)

  • Lee, Soo-Dong;Bae, Soo-Hyoung;Lee, Gwang-Gyu
    • Korean Journal of Environment and Ecology
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    • v.34 no.6
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    • pp.515-529
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    • 2020
  • Constructed wetlands undergo biological and physical changes such as an increase in the proportion of arid plants due to the natural succession process after formation. It can adversely affect not only the purification function but also the habitat of species. As such, this study aims to identify environmental factors affecting biodiversity and propose management plans based on the monitoring results of physical environmental changes and the emergence of species in seven constructed wetlands selected based on the water depth and surrounding conditions among the lands purchased by the Nakdong River basin. We examined the environmental conditions and emergence of the Odonata, which is a wetland-dependent species, to predict the trend of changes in biodiversity and abundance. The results showed that the open water area decreased as the emergent plants spread to the deep water in 2015 compared to 2012 when they were initially restored to a depth of 0.2 to 1 m. While a total of 54 dragonfly species were observed, the habitat diversity, such as vegetation, water surface, and grassland, remained similar to the initial formation of the wetlands despite the expansion of the emergent plants. On the other hand, the number of Agrionidae species, which prefer areas with fewer aquatic plants, decreased between 2012 and 2015 due to the diminished water surface. The p-values of the differences in the number of species and population between wetlands by year were 2.568e-09 and 1.162e-08, respectively, indicating the statistically significant differences. The decrease in open water surface was found to have the greatest effect on the biodiversity and habitat density of dragonflies. The time-series survey of constructed wetlands confirmed that the spread of Phragmites communis, P. japonica, Typha orientalis, etc., caused a decrease in species diversity. It suggests that environmental management to maintain the open water surface area is necessary.

Nong-ak Artist's Activities seen from the perspective of "Maiden's (娘子) Nong-ak" and 'Girls' (少女) Nong-ak" ('낭자(娘子)농악'과 '소녀(少女)농악'을 통해본 여성 농악예인의 활동)

  • Park, Hye-yeong
    • (The) Research of the performance art and culture
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    • no.32
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    • pp.209-241
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    • 2016
  • "Women's Nong-ak (農樂, Traditional Korean music performed by farmers)" was born together with "Maiden group." This study focuses on the reason why women appeared as principal agents of Nong-ak which was almost exclusive to men previously and especially, on the appearance of women Nong-ak Artists who was previously worked in Traditional Drama Troupe. This study empirically deals with details of activities of Maiden's (娘子) Nong-ak troupes and Girls' (少女) Nong-ak troupes through newspaper articles. Women Nong-ak Artists enjoyed popularity with their peculiar attractions. Participating in Nong-ak contests and collecting money for their performances, women Nong-ak Artists learned their skills form masters of Woodo Nong-ak and attracted attention with their colorful costumes. Women of Nong-ak circle especially saw through the trend of the time, expanded their arena of activities and exercised flexibility and ability to react quickly to changing situations while mixing with various genres. In particular, young girls were mobilized to show value and marketability of Korean culture as cultural medium who decorated "Pure Nong-ak art stage." They were no different from "Pretty dolls dancing like angels" who could not purse their interest and economic benefit or incite political cause and their patrons were domestic and overseas political figures. Women artists, who put Nong-ak on the stage in the name of Maiden's (娘子) Nong-ak troupes and Girls' (少女) Nong-ak after the liberation from Japanese colonial rule, contributed to expansion of market base. Women Nong-ak artists, who dominated a century in such troupes as Sadangpae, Hyuprulsa, Maiden's (娘子) Nong-ak troupes, Girls' (少女) Nong-ak troupes and Women Nong-ak troupes, were the very heroines who overturned the conventions of "male predominance (男尊女卑)" which filled Nong-ak arena and cultivated a new tradition of Nong-ak culture.

Ki Ho School of Neo-Confucianism on Yi Xue Qi Meng in Later Chosun Period (조선후기 기호성리학파의 역학계몽 이해)

  • Yi, Suhn Gyohng
    • The Journal of Korean Philosophical History
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    • no.35
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    • pp.275-308
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    • 2012
  • This article aims to investigate the studies of Yi Xue Qi Meng(易學啓蒙) performed by the researchers of Neo-Confucianism in Ki Ho region in later Chosun period. Philologically speaking, these studies were mainly performed by Han Won Jin and his colleagues. While the study of Yi Hwang(李滉)'s Qi Meng Zhuan Yi(啓蒙傳疑) performed by the researchers of Toegye(退溪) School lasts from the end of the sixteenth century to the nineteen's century, the Ki Ho(畿湖) scholars' study of Yi Xue Qi Meng are centered in the eighteenth century and hardly any significant work on this text is found before and after this century. In order to single out the distinctive features of Ki Ho School of Neo-Confucianism, this article examines three subjects the Ki Ho scholars delved into: (i) their theory of Tai Ji(太極), (ii) their theory of He-Tu(河圖) and the formation of eight trigrams, and (iii) the so-called Wu Wei Xiang De Shuo(五位相得說) discussed in one of the sections in Yi Xue Qi Meng titled the Source of He-Tu and Luo Shu[本圖書]. The Ki Ho scholars are remarkable in interpreting Tai Ji in Yi Xue Qi Meng in the context of the theory of Li-Qi and the theory of human nature. There are differences in opinion among the Ki-Ho scholars with regard to the relation between He-Tu and the formation of eight trigrams. Eventually, they withhold Zhu Xi(朱熹) and Hu Fang Ping(胡方平)'s attempt to synthesize He-Tu, the rectangular diagram of Fu Xi(伏羲)'s eight trigrams, and the circular diagram of Fu Xi's eight trigrams into one single principle. Han Won Jin tries to explain the relation between He-tu and the formation of eight trigrams in terms of the relation between He-Tu and the circular diagram, and his attempt is widely supported by his colleagues. This theory runs counter to traditional model of explaining truth. My conjecture is that such academic trend is further developed by the defenders of Practical Learning such as Hong Dae Yong(洪大容), who vigorously reject traditional system of truth and science, and that it partly explains why the study of Yi Xue Qi Meng ceases in the nineteenth century.

A study of Trend and Issue on Yulgok School's Lixue in the first half of 17c - Centering around Uiremunhae and Uiremunhaesuk (17세기 전반 율곡학파(栗谷學派) 예학(禮學)의 쟁점(爭點)과 경향(傾向) 연구 - 『의례문해(疑禮問解)』·『의례문해속(疑禮問解續)』 중심으로 -)

  • Kim, Hyunsoo
    • The Journal of Korean Philosophical History
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    • no.41
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    • pp.155-184
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    • 2014
  • This Paper is research for Yulgok School(栗谷學派)'s lixue(禮學) in the first half of 17c centering around Uiremunhae(疑禮問解) and Uiremunhaesuk(疑禮問解續). Uiremunhae and Uiremunhaesuk are a book between Kim Jangsaeng(金長生) Kim Jip(金集) and his follower's questions & answers about li. A book or letter of questions & answers about li is useful for comprehension of lixue's opinion, especially questions & answers about controversial li shows their critical mind and a foundation of cognition for li. Thus I make showing then situation of Kim Jangsaeng and his follower in relates to understanding and performing Zhuxi's family rituals on analyzing questions & answers about controversial li. Kim Jangsaeng Kim Jip and his follower's characteristic of lixue are several on analyzing Uiremunhae. First, Kim Jangsaeng and his follower researched for Zhuxi's family rituals with systematic approach and in-depth research, and detailed in reference to the Classic of li, Zhuxi, Zheongyi(程?), Zangzai(張載)'s thoery of li and chinese lixue data, and Lee Hwang(李滉), Lee Yi(李珥), Song Yikpil(宋翼弼), Jeong Goo(鄭逑)'s thoery of li and korean lixue data. Next, on questions & answers about controversial li, Kim and his follower basically maintained following Zhuxi's family rituals. Zonfa, sacrificial rituals and funeral rituals are all such that, and if there happened omission and contradiction in Zhuxi's family rituals, they refered to Zhuxi's theory of li on the collected works of Zhuxi and the analects of Zhuxi and searched righteous li by historial invesigation. Then, Kim and his follower critically were in succession to Lee Yi and Song Yikpil's thoery of li. finally, They also had to considered then situation on li(Zhuxi's family rituals' li and ancient li)'s operation and actualizatin on considering principle and mind of li.

Thailand in 2016: The Death of King Bhumibol Adulyadej and the Uncertainty in Political Economy (태국 2016: 푸미폰 국왕의 서거와 정치·경제적 불확실성)

  • KIM, Hong Koo;LEE, Mi Ji
    • The Southeast Asian review
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    • v.27 no.2
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    • pp.245-271
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    • 2017
  • The purpose of this study is to examine and assess the major characteristics and changes of politics, economy, and diplomacy in Thailand in 2016. Specifically, it reviewed the New Constitution that was passed in 2016, the confrontation between different political forces and the trend of military regime around the New Constitution, and the political instability caused by the accession of the new king to the throne. This study also set out to figure out changes to the economy and foreign relations of the country, including its relations with South Korea, under the military regime and make predictions for the impact and future prospects of King Bhumibol Adulyadej's death on the politics and economy of the country. In 2016, the politics of Thailand took a step further toward the transfer of power to civil government and established a foundation for an authoritarian system. The draft of the New Constitution, which does not seem to be democratic, was approved by a referendum and enabled the military authorities to continue their political interventions, even after the general election. The New Constitution, in particular, reduces the power of political parties itself in addition to simply keeping the Thaksin's party in check; thus, anticipating ongoing conflicts between the military authorities and political parties. In this situation, the absence of King Bhumibol Adulyadej, who used to play a decisive role in promoting the political stability of the country, and the accession of the new king to the throne raise concerns about the acceleration of political instability, which has continued after the coup and influenced the diplomatic relations of the country. Today, Thailand is distancing itself from Western nations that do not recognize the current military regime including the U.S.A. and EU member states and instead maintains a rapidly friendly and close relation with China. In 2016, the economy of Thailand made a gradual recovery rather than high growth. The death of King Bhumibol Adulyadej has exerted limited direct economic impacts only on individual consumption and tourism and is not likely to cause a recession. An economic crisis will, however, be unavoidable if the political confrontations escalate before the general election to transfer power to the civil government.

A Series of Biographies of The Collectors of Modern Archaic Art Objects of Korea 1: Jang, Taek Sang (한국 근대의 고미술품 수장가 1: 장택상)

  • Kim, Sang-yop
    • (The)Study of the Eastern Classic
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    • no.34
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    • pp.415-447
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    • 2009
  • It is encouraging fact that people are more interested in collecting modern archaic art objects of Korea with broadening spectrum of research these days. For the research in this area is significant in that it makes us learn the level of collection and appreciation which were prevalent at the end of the Josen Age by trend of preferring Occidental pictures as well as modern change in the form of collection, and enables us to reconstruct the history of modern art objects in East Asia. Except Jeon, Hyung-Pil(全鎣弼: 1906-1962), the modern collectors of Korea were not studied in details with respect to the course or contents of collection. Besides Jeon, Hyung Pil, the main modern collectors of Korea were Park, Young-cheol(朴榮喆: 1879-1939), Kim, Yong-jin(金容鎭: 1882-1968), Ham, Seok-tae(咸錫泰: 1889-?), Kim, Sung-soo(金性洙: 1891-1955), Choi, Chang-hak(崔昌學: 1891-?), Jang, Taek-sang(張澤相: 1893-1969), Kim, Chan-young(金瓚泳: 1893-?), Lee, Han-bok(李漢福: 1897-1940), Park, Chang-hun(朴昌薰: 1898-1951), Baek, In-je(白麟濟: 1898-?), Lee, Byung-jik(李秉直: -1973), et al. The object of this publication in serial form is to trace and identify the life, collected articles and contents of collection of Korean collectors who intensively collected archaic art objects in the modern age of Korea, especially, under the rule of Japanese imperialism. The first person to be introduced in this publication in serial form is Jang, Taek Sang, a leading figure in the political history of Korea. Born as the son of wealthy man, he ascended to the position of prime minister, leading a dramatic life. Being a distinguished orator, Jang, Taek Sang was well known as an appreciator and collector of picture, calligraphy and pottery. As one of the collectors of main cultural property under the rule of Japanese imperialism, Jang, Taek Sang collected countless distinguished heritages, most of which were lost during the Korean War. As he became a candidate for president to compete with Lee, Seung Man later, he sold main heritages. Thus, nearly all of the collected articles were scattered.