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The Comparative Studies on the Terrestrial Insect Diversity in Protected Horticulture Complex and Paddy Wetland (시설원예단지와 논습지의 육상곤충 다양성 비교분석)

  • Son, Jin-Kwan;Kong, Min-Jae;Kang, Dong-Hyeon;Kang, Bang-hun;Yun, Sung-Wook;Lee, Si-Young
    • Journal of Wetlands Research
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    • v.18 no.4
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    • pp.386-393
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    • 2016
  • Agricultural ecosystem is recognized as a space for providing a variety of services, in addition to the food production that it originally encompassed, such as water purification, biological habitat, air purification, soil conservation, and landscape development. The construction of greenhouses in agricultural landscapes can cause deterioration of ecosystem services because of the increase of impermeable area and loss of biological habitats. This study aimed to compare insect diversity between different types of constructed greenhouses and paddy ecosystems. The target study area was selected by considering the distribution status of horticultural complexes and was classified as Single Vinyl Greenhouse, Multi Vinyl Greenhouse or Glass Greenhouse and they were compared with four paddies. The study locations were in Gu-Mi, Bu-Yeo, Ginje and Jin-Ju. A total of 2,333 individual insects belonging to 9 orders, 38 families, 76 genus, and 80 species were collected. The composition of orders was Hemiptera (22.37%), Coleoptera (18.42%), Hymenoptera (14.47%), Orthoptera (11.84%), and Diptera (10.53%). The average number of collected species were in the order Paddy (39.38 species) > Single Vinyl Greenhouse (35.50 species) > Multi Vinyl Greenhouse (22.50 species) > Glass Greenhouse (24.00 species). The Diversity Index (H') was Paddy (4.76) > Single Vinyl Greenhouse (4.57) > Multi Vinyl Greenhouse (4.12), and Glass Greenhouse (4.12). The Richness Index (RI) was Paddy (7.72) and Single Vinyl Greenhouse (7.03) > Multi Vinyl Greenhouse (4.99) and Glass Greenhouse (5.32). From our results, it can be seen that the biological diversity features of insects decreased when greenhouses are constructed.However, Single Vinyl Greenhouse is noted to promote insect diversity more than that by Multi Vinyl Greenhouse and Glass Greenhouse. Hence, when constructing greenhouses, it is necessary to consider insect habitat to conserve insect diversity.

Comparison of Germination Characteristics and Daily Seed Germinating Pattern in 8 New Cultivars of Perennial Ryegrass Grown under Alternative and Natural Room Temperature Conditions (자연실온 및 변온환경에서 퍼레니얼 라이그래스 신품종 8종류의 발아특성 및 일일 발아패턴 비교)

  • Kim, Kyoung-Nam
    • Asian Journal of Turfgrass Science
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    • v.24 no.2
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    • pp.79-87
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    • 2010
  • Research was initiated to investigate the early establishment characteristics and germination patterns of perennial ryegrass (PR, Lolium perenne L.). Eight cultivars of PR were evaluated in the study. Experiment was conducted under a room temperature condition of $6^{\circ}C$ to $23^{\circ}C$ (natural conditions). Daily and cumulative germination patterns were measured and analyzed on a daily basis. Significant differences were observed in germination pattern, days to the first germination, days to 50% germination, days to 75% germination, and germination percentage with different environments and cultivars. Germination percentage was variable with cultivars at the end of study. It was 66.25 to 93.50% under natural conditions. There were considerable variations in the early germination characteristics and germination pattern among the entries according to different conditions. The first germination was initiated between 3 and 5 DAS (days after seeding) under ISTA (International Seed Testing Association) conditions. But it started between 6 and 8 DAS under natural conditions, being 2 to 4 days later as compared with that under ISTA conditions. It was 8 to 12 DAS that reached to days to the 50% germination, which was 2 to 5 days after the first germination. Days to the 75% germination were 10.08 to 13.70 DAS under natural conditions, being 2.07 to 5.70 days slower as compared with ISTA conditions. 'Pennant II' was the fastest cultivar. But the slowest was 'Catalina II' that was 3.62 days later than 'Pennant II' under natural conditions. Considering days to the first germination, days to 75% germination, and germination pattern etc, 'Pennant II' and 'Brightstar II' were regarded as excellent cultivars under both conditions. From this study, information on differences in germination characteristics and patterns would be usefully applied for golf course design and construction, when established with PR.

Hydraulic Assessment about Correlation of Fluvial Movement and River Bed Form on the Narrow Pass of Channel (하천 협소부에서 하상 이동성과 형태와의 상관성에 관한 하도수리학적 평가)

  • Choi, Ho-Kyun;Kim, Won-Il;Lee, Sam-Hee;Ahn, Won-Sik
    • Journal of Korea Water Resources Association
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    • v.42 no.2
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    • pp.141-148
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    • 2009
  • Each river in each country has peculiar channel characteristics at every section. Korea consists of mountains at the rate of 70%. Due to this, the sections that display unique channel form are scattered. One of the typical features is the narrow pass of channel section that presents in the process of the generation of alluvial channel and deformation channel. Around as this narrow pass of channel, it often comes to be regular flood disaster section. Regardless of this situation, investigations and plans that reflect channel characteristics at the narrow pass of channel have been wholly wanting until now. In accordance with this, we have investigated and analysed hydraulic significance and channel form of the narrow pass of channel in Seonsan in this study. The study has found real minute classification of sediment phenomenon at river bed of low flow channel on investigation section which is sand-bed river, but it was vaguely difficult to conclude that classification of sediment arises from explicit natural force. We were able to assume that the phenomenon comes from gentle bed slope, supply of river bed materials which is nearly uniformity. However, classification of sediment would come from collecting an aggregate rather than natural force. And we found that compound cross section conversion has been developing dramatically with channel form of movable bed section referring to movement which was active before at drainage district of the narrow pass of channel. With this, we could find the phenomenon that river width of low flow channel diminished largely. This kind of situation implies that it may cause compound section weighting, flood dimension decreasing, revetment at low flow channel or the local scour at bottom of levee when extraordinary flood occurs.

Suggestion for Technology Development and Commercialization Strategy of CO2 Capture and Storage in Korea (한국 이산화탄소 포집 및 저장 기술개발 및 상용화 추진 전략 제안)

  • Kwon, Yi Kyun;Shinn, Young Jae
    • Economic and Environmental Geology
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    • v.51 no.4
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    • pp.381-392
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    • 2018
  • This study examines strategies and implementation plans for commercializing $CO_2$ capture and storage, which is an effective method to achieve the national goal of reducing greenhouse gas. In order to secure cost-efficient business model of $CO_2$ capture and storage, we propose four key strategies, including 1) urgent need to select a large-scale storage site and to estimate realistic storage capacity, 2) minimization of source-to-sink distance, 3) cost-effectiveness through technology innovation, and 4) policy implementation to secure public interest and to encourage private sector participation. Based on these strategies, the implementation plans must be designed for enabling $CO_2$ capture and storage to be commercialized until 2030. It is desirable to make those plans in which large-scale demonstration and subsequent commercial projects share a single storage site. In addition, the plans must be able to deliver step-wised targets and assessment processes to decide if the project will move to the next stage or not. The main target of stage 1 (2019 ~ 2021) is that the large-scale storage site will be selected and post-combustion capture technology will be upgraded and commercialized. The site selection, which is prerequisite to forward to the next stage, will be made through exploratory drilling and investigation for candidate sites. The commercial-scale applicability of the capture technology must be ensured at this stage. Stage 2 (2022 ~ 2025) aims design and construction of facility and infrastructure for successful large-scale demonstration (million tons of $CO_2$ per year), i.e., large-scale $CO_2$ capture, transportation, and storage. Based on the achievement of the demonstration project and the maturity of carbon market at the end of stage 2, it is necessary to decide whether to enter commercialization of $CO_2$ capture and storage. If the commercialization project is decided, it will be possible to capture and storage 4 million tons of $CO_2$ per year by the private sector in stage 3 (2026 ~ 2030). The existing facility, infrastructure, and capture plant will be upgraded and supplemented, which allows the commercialization project to be cost-effective.

Management Guidelines on the Large Old Trees as the Natural Monuments in Seoul, Incheon, and Gyeonggi Province through the Analysis of the Growing Environment (생육환경 분석을 통한 서울·인천·경기지역 천연기념물 노거수의 관리방안)

  • Lee, Seung Je
    • Korean Journal of Heritage: History & Science
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    • v.42 no.1
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    • pp.88-99
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    • 2009
  • This study was conducted to formulate management guidelines for Natural monumental old trees in Korea through survey of tree vigor and analysis of growing environments. A total of 20 old trees designated as natural monuments in Seoul, Incheon, and Gyeonggi Province were surveyed. The biological characteristics were surveyed with 4 items of species, ages and height of trees. The surrounding environments were surveyed with 2 items of location types and surroundings. The root conditions were surveyed with 2 items of denudation and molding depth. The health conditions were surveyed with 5 items of withering rate, cavity size, bark breakaway rate, damages by blight and insects, and growing tips. The soil conditions were surveyed with 6 items of PH, organic contents, valid phosphoric acid, transposal cations(K, Ca) and soil compaction. On the basis of outcomes of these research items, mutual relations among locations, growings and soil conditions of old trees were analyzed by carring out cross tabulation, correlation, and simple and multiple regression. Management guidelines were presented searching the factors effecting on the health of the monumental old trees. On the biological characteristics, the old trees designated as natural monuments were Pinus bungeana(4 trees), Juniperus chinensis(3 trees), Ginkgo biloba(3 trees), Poncirus trifoliata(2 trees). Actinidia arguta, Wisteria floribunda, Thuja orientalis, Quercus mongolica, Sophora japonica, Fraxinus rhynchophylla, Zelkova serrata, and Pinus densiflora. The tree height ranged from 4.2 to 39.2m, and root collar rounds ranged from 1.01 to 15.2m. On the surrounding environments, The location types ; Gardens(4), historical sites(5), residental sections(3) open agricultural fields(3), mountain hills(3), and near ocean beaches(1) and stream site(1). The surroundings ; 75% denudation of roots, molded more than 10cm except 4 trees(25%). On the health conditions, 1)Withering rate ; Ginkgo biloba(20%) in Yongmoon temple, (5%) in Saki-ri, kanwha-gun, and others had no withering rate. 2) Cavity size ; all subject had $5{\sim}100cm^3$ of cavity. 3) Bark breakaway rate ; Pinus bungeana in Soosong-dong, in the shrine of Confucius, in Samchung-dong, especially high rate of cavity(5~50%) in Seoul area and in Saki-ri, Kangwha-gun were high 45% brakeaway rate. 4) Damages by blight and insects was slight due to managements. 5Growing tips ; In cases of Juniperus chinensis in Changdeok palace and SunnogDang, seoul, growing tips were 1/2, presumably cause by air pollution, and in cases of Fraxinus rhynchophylla in Paju city and Pinus densiflora in BacksaDorip-ri, Icheon city, growing tips were fine, presumably because there were no moldings. On the Soil conditions, Soil pH ranged from 5.2 to 8.3, organic matter contents from 12% to 56%, phosphorus contents from 104 to 618ppm, soil compaction ranged from 7 to 28mm( among them, Denudation was severe with 21~28mm soil compactions in cases of Pinus bungeana in Soosong -dong, Thuja orientalis in Samchung -dong, Ginkgo biloba in the shrine of Confucius and in Yongmoon temple.) Results of cross tabulation, correlation, and regression analysis showed that molding depth was the most serious factor to deteriorate the tree vigor and cambium conductivity. In addition, soil acidity, organic matter contents, disease and insect damages and cambial detachment were also related to the tree vigor. Additional research of these relationships will be needed to conduct more detailed studies. Based on the relationships between the tree vigor and growing environments, it is considered that old trees should be managed to give them more growing spaces and less abuses. Also, molded soils should be removed and further soil-molding around the tree collar should be prohibited. For the construction of systematic management and removal of harmful factors, appropriative management according to spices, persistent monitering of damaged cases and construction of management system through the accumulation of data on the relationships of soil conditions are required.

A Study On Irrigation Water Price Structure and Prescription (농업용수의 가격구조에 관한 연구)

  • 심기영
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.15 no.4
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    • pp.3170-3180
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    • 1973
  • This study of the subject will review past and present irrigation development in Korea. Particular attention will be given to water pricing structure and a case study on the purpose of rational operation and management of irrigation water and organizations, and the optimum irrigation water and organizations, and the optimum irrigation water fee inorder to reduce farmers burden and to rationalize the farmland associations management so as to achieve development of the rural environment. In 1971, the reservoir of the Farmland Improvement A sociation (FIA) produced only 775 millison $m^3$ of irrigation water or 77% of planned capacity of 1,015 million $m^3$. It was caused by inefficient maintenance of irrigation facilities; for instance, about 21% of reservoirs, pumping stations and weirs in Korea have been silted by soil erosion which hinder to water production according to an ADC survey. The first Irritation Association was established in 1906, whcih was renamed the Farmland Assoeiation by the Rural Development Enouragement Law in 1970. By the end of 1971, 411,000 ha of rice paddies were under the control of 267 associations nationwide. The average water price assessed by Associations nationwide rose from 790 won per 0.1 ha. in 1966 to 1,886 won in 1971. The annual growth rate was 20%. The highest water price in 1971 was 4,773 won her 0.1 ha. and the lowest was 437 won. This range was caused by differences in debt burden, geographic conditions and management efficiency among the Associations. In 1971, the number of Associations which exceeded the average water price of 1,886 won per 0.1 ha. was 144, or 55.1% of all Association. In determination of water price, there are two principles; one is determined by production cost such as installation cost of irrigation facilities, maintenance cost, management cost and depreciation ect. For instance, the Yong San River Development project was required 33.7 billion won for total construction and maintenance cost is 3.1 billion won for repayment, maintenance and management cost per year. The project produces 590 million $m^3$ of irrigation water annually. Accordingly, the water price per $m^3$ is 5.25 won. The other principle is determined by water value in the crop products and in compared with production of irrigated paddy and non-irrigated paddy. By using this method, water value in compared with paddy rice vs. upland rice(Average of 1967-1971) was 14.15 won per $m^3$ and irrigated paddy vs. non-irrigated paddy was 2.98 won per $m^3$. In contrast the irrigation fee in average association of 1967-1971 was 1.54 won per $m^3$. Accordingly, the current national average irrigation fee(water price) is resonable compared with its water value. In this study, it is found that the ceiling of water price in terms of water value is 2.98 won per $m^3$ or 2,530 won per 0.1 ha. However, in 1971 55% of the associations were above the average of nationwide irrigation fees. which shows the need for rationalization of the Association's management. In connection with rationalization of the Association's management, this study recommends the following matters. (1) Irrigation fee must be assessed according to the amount of water consumption taking intoaccount the farmer's ability. (2) Irrigation fee should be graded according to behefits and crop patterns. (3) Training personnel in the operation and procedures of water management to save O&M costs. (4) Insolvent farmland association should be integrated into larger, sound associations in the same GUN in order to reduce farmers' water cost. (5) The maintenance and repair of existing irrigation facilities is as important as expansion of facilities. (6) Establishment of a new Union of Farmland Association is required to promoted proper maintenance and to protect the huge investment in irrigation facilities by means of technical supervision and guidance.

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A Dynamic Management Method for FOAF Using RSS and OLAP cube (RSS와 OLAP 큐브를 이용한 FOAF의 동적 관리 기법)

  • Sohn, Jong-Soo;Chung, In-Jeong
    • Journal of Intelligence and Information Systems
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    • v.17 no.2
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    • pp.39-60
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    • 2011
  • Since the introduction of web 2.0 technology, social network service has been recognized as the foundation of an important future information technology. The advent of web 2.0 has led to the change of content creators. In the existing web, content creators are service providers, whereas they have changed into service users in the recent web. Users share experiences with other users improving contents quality, thereby it has increased the importance of social network. As a result, diverse forms of social network service have been emerged from relations and experiences of users. Social network is a network to construct and express social relations among people who share interests and activities. Today's social network service has not merely confined itself to showing user interactions, but it has also developed into a level in which content generation and evaluation are interacting with each other. As the volume of contents generated from social network service and the number of connections between users have drastically increased, the social network extraction method becomes more complicated. Consequently the following problems for the social network extraction arise. First problem lies in insufficiency of representational power of object in the social network. Second problem is incapability of expressional power in the diverse connections among users. Third problem is the difficulty of creating dynamic change in the social network due to change in user interests. And lastly, lack of method capable of integrating and processing data efficiently in the heterogeneous distributed computing environment. The first and last problems can be solved by using FOAF, a tool for describing ontology-based user profiles for construction of social network. However, solving second and third problems require a novel technology to reflect dynamic change of user interests and relations. In this paper, we propose a novel method to overcome the above problems of existing social network extraction method by applying FOAF (a tool for describing user profiles) and RSS (a literary web work publishing mechanism) to OLAP system in order to dynamically innovate and manage FOAF. We employed data interoperability which is an important characteristic of FOAF in this paper. Next we used RSS to reflect such changes as time flow and user interests. RSS, a tool for literary web work, provides standard vocabulary for distribution at web sites and contents in the form of RDF/XML. In this paper, we collect personal information and relations of users by utilizing FOAF. We also collect user contents by utilizing RSS. Finally, collected data is inserted into the database by star schema. The system we proposed in this paper generates OLAP cube using data in the database. 'Dynamic FOAF Management Algorithm' processes generated OLAP cube. Dynamic FOAF Management Algorithm consists of two functions: one is find_id_interest() and the other is find_relation (). Find_id_interest() is used to extract user interests during the input period, and find-relation() extracts users matching user interests. Finally, the proposed system reconstructs FOAF by reflecting extracted relationships and interests of users. For the justification of the suggested idea, we showed the implemented result together with its analysis. We used C# language and MS-SQL database, and input FOAF and RSS as data collected from livejournal.com. The implemented result shows that foaf : interest of users has reached an average of 19 percent increase for four weeks. In proportion to the increased foaf : interest change, the number of foaf : knows of users has grown an average of 9 percent for four weeks. As we use FOAF and RSS as basic data which have a wide support in web 2.0 and social network service, we have a definite advantage in utilizing user data distributed in the diverse web sites and services regardless of language and types of computer. By using suggested method in this paper, we can provide better services coping with the rapid change of user interests with the automatic application of FOAF.

The meaning based on Yin-Yang and Five Elements Principle in Semantic Landscape Composition of 'the Forty Eight Poems of Soswaewon' ('소쇄원(瀟灑園) 48영'의 의미경관 구성에 있어서 음양오행론적(陰陽五行論的) 의미(意味))

  • Jang, Il-Young;Shin, Sang-Sup
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.2
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    • pp.43-57
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    • 2013
  • The purpose of this study is to identify potential semantic landscape makeup of "the Forty Eight Poems of Soswaewon" according to Yin-Yang and Five Elements Principle(陰陽五行論). that speculation system between human's nature and cosmical universal order. Existing academic discussions made so far concerning this topic can be summed up as follows: 1. Among Yin-Yang-based landscape makeups of the Forty Eight Poems of Soswaewon, poetic writings for embodiment of interactions between nature and human behaviors focused on depicting dynamic aspects of a poetic narrator when he appreciates or explores hills and streams as of to live free from worldly cares. Primarily, many of those writings were created on the east and south primarily through assignment of yang. On the other hand, poetic writings for embodiment of nature and seasonal scenery - as static landscape makeup of yin - were often created on or near the north and west for many times. Those writings focusing on embodiment of nature and artificial scenery as a work are divided into two categories: One category refers to author Kim In-hu's expression of semantic landscape from seasonal scenery in nature. The other refers to his depiction of realistic garden images as they are. In the Forty Eight Poems of Soswaewon, the poetic writings show that author Kim focused on embodying seasonal scenery rather than expressing human behaviors. In addition, both Poem No. 1 and Poem No. 48(last poem; titled 'Jangwon Jeyeong') were created in a same place, which author Kim sought to understand the place as a space of beginning and end where yin and yang - i.e. the principle of natural cycle - are inherent. 2. According to construction about landscape in the Forty Eight Poems of Soswaewon on the basis of Ohaeng-ron (five natural element principle), it was found that tree(木) and fire(火) are typical examples of a world combined by emanation. First, many of poetic writings depicting the sentiments of tree focused on embodying seasonal scenery and were located in the place of Ogogmun(五曲門) area in the east, from overall perspective of Soswaewon. The content of these poems shows generation and curve / straightness in flexibility and simplicity. Many of poems depicting the sentiments of fire(火) focused on embodying human behaviors, and they were created in Aeyangdan area on the south of Soswaewon over which sun rises at noon. These poems are all on a status of side movement that is characterized by emanation and ascension which belong to attributes of yang. 3. With regard to Ohaeng-ron's interpretation about landscape in the Forty Eight Poems of Soswaewon, it was found that metal(金) and water(水) are typical examples of world combined by convergence. First, it was found that all of poems depicting sentiments of metal focused on embodying seasonal scenery, and were created in a bamboo grove area on the west from overall perspective of Soswaewon. They represent scenery of autumn among 4 seasons to symbolize faithfulness vested in a man of virtue(seonbi) with integrity and righteousness. Poems depicting sentiments of water were created in vicinity of Jewoldang on the north, possibly topmost of Soswaewon. They were divided into two categories: One category refers to poems embodying actions of welcoming the first full moon deep in the night after sunset, and the other refers to poems embodying natural scenery of snowscape. All of those poems focused on expressing any atmosphere of turning into yin via convergence. 4. With regard to Ohaeng-ron's interpretation of landscape in the Forty Eight Poems of Soswaewon, it was found that poems depicting sentiments of earth(土), a complex body of convergence and emanation, were created in vicinity of mountain stream around Gwangpunggak which is located in the center of Soswaewon. These poems focused on carrying actions of author Kim by way of natural phenomena and artificial scenery.

Establishment of Buddhist Monks' Pungmul in the Late Joseon Dynasty and Its Meanings (조선 후기 절걸립패 풍물의 성립과 그 풍물사적 의의)

  • Son, Tae-do
    • Korean Journal of Heritage: History & Science
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    • v.50 no.1
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    • pp.78-117
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    • 2017
  • Buddhism, which was subject to repression all over the early Joseon Dynasty, received a certain recognition from the state, because Buddhist monks had participated in the war of the Japanese invasion in 1592. On the other hand, however, one of the results was the destruction of many temples. In the late Joseon Dynasty, the Buddhist monks themselves acted as players of Pungmul(people's percussive band music) for the rebuilding of Buddhist temples. These so-called "the Buddhist monks' Pungmul" is the imitation of former clowns' Pungmul and farmers' one that sometimes request money or rice at houses of villages. In the late Joseon Dynasty, the activities of the Buddhist monks' Pungmul were held all over the country. Today, there are "Bitnae Nongak(farmers'percussive band music)" in Kyeongsangbuk-do, "Beokku-noli(the drum play) in the areas of Yeosu and Gangjin in Jeollanam-do, the song of the Buddhist monks' Pungmul for the people's house spirits in the Gyeonggi-do, Gangwon-do and Chungcheong-do, and Namsadang-pae(the nomadic entertaining groups composed of only men), as clear pictures of it. In these things related to Nongak or Nongak relevant affairs, the shapes of the Buddhist monks' Pungmul in the late Joseon Dynasty remain clear. On the other hand, today the Namsadang-pae, which was formed as a result of Buddhist monks' Pungmul in the late Joseon Dynasty, was left only in the Chungcheong-do and Gyeonggi-do, because the temple construction in the Gyeonggi-do was made especially many in the late Joseon Dynasty. During the late Joseon Dynasty, the Buddhist monks' Pungmul, which had long-lived and had taken place throughout the nation, had a great impact on Pungmul. There are the Buddhist elements, such as Gokkal(the Buddhist monk's peaked hat), paper flowers, the color band, the small drum, and Bara(small cymbals) are often found in the Pungmul of Korea. In the late period of the Joseon Dynasty, it is obviously important place in the Pungmul history of Korea. Research and studies on this subject should be made more in the future.

Temporal and Spatial Variability of Phytoplankton Communities in the Nakdong River Estuary and Coastal Area, 2011-2012 (2011-2012년 낙동강 하구 및 연안역에서 식물플랑크톤 군집의 시·공간적 변화)

  • Chung, Mi Hee;Youn, Seok-Hyun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.4
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    • pp.214-226
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    • 2013
  • To understand the changing patterns in phytoplankton communities, we conducted 12 surveys along the Nakdong River, its estuary, and adjacent coastal areas between January 2011 and October 2012 (during the period of barrage construction and sediment dredging). Monthly precipitation ranged from 0 to 502 mm during the survey period, and salinity ranged between 0.1 psu and 0.3 psu in the Nakdong River, regardless of the depth, indicating no seawater influence, while salinity showed large seasonal fluctuations in the estuarine and coastal station, ranging from 0.1 psu to 34.8 psu. A total of 402 phytoplankton species were identified, 178 species from the river and 331 species from the estuary and coastal areas. Phytoplankton standing crop increased in 2012 compared to that in 2011, and was found to be highest in the river, followed by the estuary and coastal areas. Among the top 20 species in frequency of occurrence and dominance, Stephanodiscus spp., Aulacoseira granulata, and Aulacoseira granulata var. angustissima and Pseudo-nitzschia spp. were important species along the river-estuary-coastal areas. Diatoms were the major taxonomic group inhabiting the Nakdong river-estuary-coastal areas. A comparison of seasonal dominant phytoplankton species revealed a slight decrease over the years, from 13 species in 2011 to 10 species in 2012. However, no significant difference was found in the diversity of phytoplankton species between the two survey years, although lightly greater diversity was observed in the coastal areas than in the river and estuary. Cluster analysis with community composition data revealed that the community structure varied significantly in 2011 depending on the time of survey, while in 2012, it hardly showed any variation and was simpler. An increase in the phytoplankton standing crop, fewer dominant species, and simpler community structure in 2012 compared to those in 2011 are probably due to the rapid environmental changes along the Nakdong River. To investigate these ecological relationships, it is necessary to conduct further studies focusing on integrated analyses of biocenosis, including phytoplankton with respect to the changes in nutrient distribution, variation of freshwater discharge, and effect area of freshwater in the Nakdong estuary and adjacent coastal areas.