• Title/Summary/Keyword: Ecological research

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Studies on Distribution and Ecology of Clithon retropictus (Martens, 1879) in South Korea (한국산 기수갈고둥의 분포 및 생태에 관한 연구)

  • Han, Seung Pil;Hwang, In Chul;Kwon, Soon Jik
    • Journal of Wetlands Research
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    • v.23 no.4
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    • pp.317-326
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    • 2021
  • The present study was carried out with a view to understand the distribution and ecology of Clihton retropictus (Martens, 1879), a class II endangered wildlife designated and protected by the Ministry of Environment, Republic of Korea, and to suggest the effective conservation and management measures for this species and its habit. First, the distribution of Clihton retropictus was investigated nationwide, and environmental factors such as salinity and substratum were analyzed in consideration of the ecological characteristics of this species. In addition, the individual size, density, and movement of Clihton retropictus per each district surveyed were analyzed. Due to its nature of inhabiting in the brackish water zone, the analysis showed that the salinity of this species was 0.7 ~ 16.6‰ at low tide and 1.0 ~ 17.3% at high tide. It was learned from the analysis of substratum that its composition in each river under investigation was slightly different, but most of substratum had a higher composition ratio than gravel (pebble, 16 ~ 64 mm). On the other hand, the size of each individual was checked by measuring the length of its diameter, and there was almost no change in the individual when the inhabited range of Clihton retropictus was short. However, there was tendency that the longer the habitat range, the bigger the individual size. From surveying the population density by season, it was made clear that, during the summer (July to August) and fall (September to October), the density was relatively higher while the number of individuals decreased significantly during winter (November to December) when the water temperature was lowered. In an effort to effectively establish conservation and management measures, the moving distance was measured, and it became known that, during the surveys in summer and fall when the individuals were active, the individuals moved in more distances than during the winter survey. The results of this study are expected to be utilized as basic data for establishing effective management plans such as creation of habitats for Clihton retropictus, its migration projects and selection of migration destinations which get unavoidable due to development projects.

Searching for a Curriculum to Reconceptualize Sexuality for Youth Sex Education : Nth Room Era, New Talk of 'Body' and 'Sex' from a Feminist Theological Point of View (청소년 성교육을 위한 성성(性性)의 재개념화 커리큘럼 모색 : N번방 시대, 여성신학적 관점에서 '몸'과 '성'을 새롭게 이야기하다)

  • Lee, Jooah
    • Journal of Christian Education in Korea
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    • v.67
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    • pp.301-337
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    • 2021
  • The researcher looked at the differences in views and various controversies surrounding Korean youth sexuality education in the wake of the Nth Room incident, which had a great impact on modern Korean society. Sex education for adolescents in Korea can be divided into public sex education through school sex education and the Youth Sexuality Center, and conservative/traditional Protestant sex education. Public sex education is partly influenced by feminist sexual ethics and comprehensive sex education abroad. Based on gender sensitivity and the right to sexual self-determination, four major projects are prevention of sexual harassment, prostitution, sexual violence, and domestic violence. However, the school sex education standard was criticized for stereotypes of gender roles and gender-discriminatory content, reinforced distorted myths about sexual violence, and exclusion of sexual diversity and various family types. Conservative/traditional Protestantism is based on the normal family ideology such as bisexual marriage, premarital chastity, and sexual ethics recognized only within marital relationships. It is a form of confrontation with public sex education while strongly opposing it. The researcher first analyzed the characteristics of public sex education, conservative/traditional Protestant sexual ethics and sex education, feminist sex ethics and sex education, and overseas youth sex education, respectively, while composing the curriculum for Korean youth sexuality education. And as a more fundamental solution to youth sexuality education, I pointed out that there are limits to asceticism, premarital chastity, gender sensitivity and sexual self-determination education, and found an alternative to the concept of body and sex in feminist theology. The researcher pointed out that it is necessary to reconceptualize the body and sex under the recognition that the most fundamental cause of distorted sexual culture is dualistic sex and understanding the body, centering on the research of various feminist theologians. And this was conceptualized into three concepts: holistic sexuality, mutual solidarity understood in relationships with others, and sexuality as a spirituality that extends to the global community. And with each curriculum, 1) Holistic Sexuality: Breathing, Narrative, Making the Shape of One's Body and Mind 2) mutual solidarity : Feeling the Breath of Others, Media Literacy through Conscientization, Sending a Good Wind 3) Sexuality as a spirituality that extends to global concern: It was proposed to pay attention to nature and to co-cultivate it, to listen to the earth's moans and create a new way of life, and to write a prayer with the earth and fellow living beings.

The long-term decay rate and nutrient dynamics during leaf litter decomposition of Pinus densiflora and Pinus thunbergii (한반도 중부지역 조림지 소나무와 곰솔의 장기적 낙엽 분해율 및 분해과정에 따른 영양염류 동태변화)

  • Lee, Il-hwan;Jo, Soo-un;Lee, Young-sang;Won, Ho-yeon
    • Korean Journal of Environmental Biology
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    • v.39 no.3
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    • pp.374-382
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    • 2021
  • In the present study, we analyzed the decay rate and nutrient dynamics during leaf litter decomposition of Pinus densiflora and Pinus thunbergii in Gongju for 60 months, from 2014 to 2019. P. thunbergii leaf litter decomposed faster than that of P. densiflora. The decay constant of P. densiflora and P. thunbergii leaf litter after 60 months was 3.02 and 3.59, respectively. The initial C/N ratio of P. densiflora and P. thunbergii leaf litter were 14.4 and 14.5, respectively. After 60 months, C/N ratio of decomposing P. densiflora and P. thunbergii leaf litter decreased to 2.26 and 3.0, respectively. The initial C/P ratio of P. densiflora and P. thunbergii leaf litter were 144.1 and 111.3. After 60 months elapsed, the C/P ratio of decomposing P. densiflora and P. thunbergii leaf litter decreased to 40.1 and 45.8, respectively. After 60 months, the percentage of the remaining N, P, K, Ca, and Mg in decomposing P. densiflora leaf litter was 231.08, 130.13, 35.68, 48.58, and 36.03%, respectively. After 60 months, the percentage of the remaining N, P, K, Ca, and Mg in decomposing P. thunbergii leaf litter was 143.91, 74.02, 28.59, 45.08, and 44.99%, respectively. The findings of the present study provide an insight into the forest ecosystem function of coniferous forests through the analysis of the amount of nutrient transfer into the soil through a long-term decomposition process; this information is intended to be used as basic data for preparing counter measures for future climate and ecosystem changes.

Forest Vegetation Structure in Maruguem(the Ridge Line) Area of Dakmokryeong to Daetjae, the Baekdudaegan (백두대간(닭목령-댓재 구간) 마루금 주변의 산림식생구조)

  • Song, Ju-Hyeon;Kwon, Jino;Yun, Chung-Weon
    • Korean Journal of Environment and Ecology
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    • v.33 no.1
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    • pp.28-51
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    • 2019
  • The purpose of this study was to analyze forest vegetation structure in Marugeum (the ridge line) area between Dakmokryeong and Daetjae in Baekdudaegan through vegetation classification, importance value, species diversity, and CCA using the data that were collected from 245 quadrates through Braun-Blanquet vegetation survey method from May to September in 2017. The results of the forest vegetation classification identified 8 vegetation units with Quercus mongolica community group at the highest level. Q. mongolica community group was classified into the Cornus controversa community, Buxus koreana community, Sasa borealis community, Abies nephrolepis community, and Q. mongolica typical community. C. controversa community was further classified into Quercus dentata group, Filipendula glaberrima group, Larix kaempferi group, and C. controversa typical group. The result of the important value analysis showed that Q. dentata had the highest importance value at 19.1% in vegetation unit 1 while Q. mongolica had the highest importance value at 22.7%, 38.3%, 25.6%, 41.3%, 27.9%, and 41.6% in vegetation unit 2, 4, 5, 6, 7, and 8, respectively, and L. kaempferi had the highest importance value at 27.6% in vegetation unit 3. As such, Q. mongolica species generally represented the communities of Marugeum (the ridge line) area of Dakmokryeong to Daetjae in Baekdudaegan. The results of species diversity showed that vegetation unit 1 and 2 were 3.305 and 3.236, respectively, which were relatively higher than other vegetation units. It was considered that this result was due to the influence of high emergence of present species. The results of the CCA analysis of the correlations between biotic environmental factors and vegetation types showed that vegetation unit 1 was mainly correlated with the megaphanerophyte ratio and vine plant ratio. In the correlations between abiotic environmental factors and vegetation types, vegetation unit 7 was significantly correlated with altitude. From the perspective of ecological management, vegetation unit 5 represented by B. koreana community was inhabited by a variety of plants due to the species composition and location environment due to the geological characteristics that are typical of limestone area. Vegetation unit 7 represented by A. nephrolepis community was typified as subalpine vegetation widely distributed by relict species and endemic species. We concluded that it is necessary to manage these vegetation units with an ecologically differentiated approach.

The Effect of CO2 Fixation for Microalgae based on CO2 Concentration and Flow Rate (이산화탄소 농도 및 유속에 따른 하천 내 미세조류의 이산화탄소 고정 효과)

  • Park, Hyomin;Lee, Sangdon
    • Journal of Wetlands Research
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    • v.20 no.4
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    • pp.363-369
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    • 2018
  • One of the recent environmental problems is climate change due to the increase of atmospheric $CO_2$, which causes ecological changes and various environmental problems. Therefore, various studies are being carried out to reduce $CO_2$ in the world in order to solve various environmental problems caused by increase of $CO_2$. The $CO_2$ reduction using microalgae is an environmentally friendly method by using photosynthesis reaction of microalgae. However, most studies using single species. There is no study on the $CO_2$ fixing efficiency of microalgae in natural rivers. Therefore, this study was to identify the microalgae in the Sum river and to analyze the growth characteristics of microalgae in the river to obtain optimal culture conditions. And the changes of biomass and chlorophyll-a of microalgae were analyzed according to $CO_2$ concentration and injection rate. The purpose of this study was to investigate the fixing efficiency of carbon dioxide in microalgae in natural rivers. Six kinds of dominant species were observed as a result of the identification of microalgae in Sum river(Ankistrodesmus falcatus, Scenedesmus intermedius, Selenodictyum sp., Xanthidium apiculatum var. laeve, Cosmarium pseudoquinarium, Dictyosphaerium pulchellum). All of these species were green algae. Biomass and chlorophyll-a increased with the increase of $CO_2$ concentration and biomass and chlorophyll-a increased faster flow rate at the same $CO_2$ concentration. Also, the quantity of $CO_2$ fixation on the microalgae tended to be higher when the flow rate of injected gas was faster. This study can be referred as being significant in the micro-algae in river. In addition, the optimal conditions for $CO_2$ fixation of microalgae in rivers and the quantification of the quantity of $CO_2$ fixation from microalgae in rivers can be used as basic data for future policy of $CO_2$ reduction.

A Study on Characteristics of the Vegetation Structures and Vegetation Landscape Management in the Cultural Landscape Forest of Unmun Temple, Cheongdo-gun, Korea (청도군 운문사 문화경관림 식생구조 특성과 식생경관 관리방안 연구)

  • Lee, Do-I;Han, Bong-Ho;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.47 no.3
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    • pp.81-92
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    • 2019
  • This study was conducted to establish vegetation structure characteristics and vegetation management plan of the cultural landscape forests located around Unmun Temple in Cheongdo-gun and to provide the basic data needed to manage the cultural landscape forests. The landscape characteristics are analyzed in two perspectives including the landscape as viewed from inside and outside of Unmun Temple and eight landscape views are selected. Main views are Pinus densiflora forest and Abies holophylla forest around Unmun Temple. As a result of the survey of existing vegetation around Cheongdo-gun Unmun Temple, P. densiflora forests and P. densiflora-A. holophylla forests are widely distributed, occupying 79.2% of the forest. The plant community structure was classified into seven types according to the three topographic characteristics, flat forests, slope forests, and lower forests, Which were divided into a total of 30 survey plots and the average relative importance percentage was determined. The P. densiflora community on the flat are dominated by Carpinus tschonoskii in Under-canopy. The P. densiflora-A. holophylla community on the flat had a relatively high rate of domination in the shrubs. There were no competing species for the A. holophylla community on the plat. The large standard P. densiflora and the small standard P. densiflora were expected to be confined by P. serrulata var. pubescens and the Quercus variabilis on the slopes. The managed P. densiflora community had a relatively high rate of P. densiflora domination in the shrubs. The P. densiflora community on the lowland was dominated by Styrax japonicus and P. serrulata var. pubescens. The Shannon species diversity index was 0.2360 to 1.4088. The results of the correlation analysis with P. densiflora, A. holophylla and other species were P. densiflora had negative correlation with Acer mono, Corylus heterophylla var. heterophylla, Zelkova serrata and A. holophylla, and A. holophylla have negative correlation with S. japonicus and P. densiflora. Landscape characteristics and plant community structures are analyzed to propose management methods of maintaining and restoring The P. densiflora and A. holophylla cultural forest landscapes around Unmun Temple.

A Study on the Meaning Landscape and Environmental Design Techniques of Yoohoedang Garden(Hageowon : 何去園) of Byulup(別業) Type Byulseo(別墅) (별업(別業) '유회당' 원림 하거원(何去園)의 의미경관 해석과 환경설계기법)

  • Shin, Sang-sup;Kim, Hyun-wuk
    • Korean Journal of Heritage: History & Science
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    • v.46 no.2
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    • pp.46-69
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    • 2013
  • The results of study on the meaning landscape and environmental design techniques of the Byulup, Yoohoedang garden(Hageowon) based on the story in the collection of Kwon Yi-jin (Yoohoedangjip, 有懷堂集), are as below. First, Yoohoedang Kwon Yi-jin (有懷堂 權以鎭 : 1668~1734) constructed a Byulup garden consisting of ancestor grave, Byulup, garden, and a school, through 3 steps for 20 years in the back hill area of Moosoo-dong village, south of Mountain Bomun in Daejeon. In other words, he built the Byulup(別業, Yoohoedang) by placing his father's grave in the back hill of the village, and then constructed Yoegeongam(餘慶菴) and Geoupjae(居業齋) for protection of the pond(Napoji, 納汚池), garden(Banhwanwon, 盤桓園), and ancestor graves, and descendants' studying in the middle stage. He built an extension in Yoohoedang and finally completed the large-size garden (Hageowon) by extending the east area. Second, in terms of geomancy sense, Yoohoedang Byulup located in Moosoo-dong village area is the representative example including all space elements such as main living house (the head family house of Andong Kwon family), Byulup (Yoohoedang), ancestor graves, Hagoewon (garden) and Yoegeongam (cemetery management and school) which byulup type Byulseo should be equipped with. Thirdly, there are various meaning landscape elements combining the value system of Confucianism, Buddhism and Taoism value, including; (1) remembering parents, (2) harmonious family, (3) integrity, (4) virtue, (5) noble personality, (6) good luck, (7) hermit life, (8) family prosperity and learning development, (9) grace from ancestors, (10) fairyland, (11) guarding ancestor graves, and (12) living ever-young. Fourth, after he arranged ancestor graveyard in the back of the village, he used surrounding natural landscapes to construct Hagoewon garden with water garden consisting of 4 mountain streams and 3 ponds for 13 years, and finally completed a beautiful fairyland with 5 platforms, 3 bamboo forests, as well as the Seokgasan(石假山, artificial hill). Fifth, he adopted landscape plantation (28 kinds; pine, maple, royal azalea, azalea, persimmon tree, bamboo, willow, pomegranate tree, rose, chinensis, chaenomeles speciosa, Japanese azalea, peach tree, lotus, chrysanthemum, peony, and Paeonia suffruticosa, etc.) to apply romance from poetic affection, symbol and ideal from personification, as well as plantation plan considering seasonal landscapes. Landscape rocks were used by intact use of natural rocks, connecting with water elements, garden ornament method using Seokyeonji and flower steps, and mountain Seokga method showing the essence of landscape meanings. In addition, waterscape are characterized by active use of water considering natural streams and physio-graphic condition (eastern valley), ecological corridor role that rhythmically connects each space of the garden and waterways following routes, landscape meaning introduction connecting 'gaining knowledge by the study of things' values including Hwalsoodam(活水潭, pond), Mongjeong(蒙井, spring), Hosoo(濠水, stream), and Boksoo(?水, stream), and sensuous experience space construction with auditory and visualization using properties of landscape matters.

Analysis of Environmental Factors and Change of Vascular Plant Species along an Elevational Gradients in Baekdansa, Mt. Taebaeksan National Park (태백산국립공원 백단사코스의 고도별 관속식물상 변화와 환경요인 분석)

  • An, Ji-Hong;Park, Hwan-Joon;Lee, Sae-rom;Seo, In-Soon;Nam, Gi-Heum;Kim, Jung-Hyun
    • Korean Journal of Environment and Ecology
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    • v.33 no.4
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    • pp.378-401
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    • 2019
  • This study generated a list of plants in eight sections from the Baekdansa ticket office (874m) to Cheonjedan (1,560m) divided in the interval of 100m above sea level to examine the species diversity patterns and distribution changes of the vascular plants at different altitudes in Taebaeksan National Park. Four site surveys found a total of 385 taxa: 89 families, 240 genera, 345 species, 5 subspecies, 34 varieties, and 1 form. A result of analyzing the change of species diversity along elevational gradients showed that it decreased with increasing elevation and then increased from a certain section. A result of analyzing habitat affinity types showed that the proportion of forest species increased with increasing elevation. On the other hand, the ruderal species appeared at a high rate in the artificial interference section. A result of comparing the proportion of woody and herb plants showed that the woody plants gradually increased with elevation and rapidly decreased in the artificial interference section. On the other hand, the herb plants showed the opposite trend. A result of analyzing the change of distribution of species according to altitude with the DCA technique showed that the vascular plants were divided into three groups according to the elevation in order on the I axis with the boundaries at 900m and 1,300m above sea level. The arrangement of each stand from right to left along the altitude on the I axis with a significant correlation with warmth index (WI) confirmed that the temperature change along the altitude could affect the distribution of vascular plants, composition, and diversity. Therefore, the continuous monitoring is necessary to confirm ecological and environmental characteristics of vegetation, distribution ranges, changes of habitat. We expect that the results of this study will be used as the basic data for establishing the measurement measures related to the preservation of biodiversity and climate change.

Study on Korea Social Perceptions on the Forest Fires of Newspaper Analysis (신문사설 분석을 통한 산불에 대한 사회적 인식연구)

  • Kim, Bomi;Park, Joowon
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.88-96
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    • 2019
  • The purpose of this study is to understand when forest fire as a natural phenomenon becomes constructed as social issues in Korea; how the forest fire-related discourses in the editorials reflecting the social perceptions have been changed regarding the principal subject and the measures of the forest fire management; and whether the social perception on the forest fire affects the forest fire policy of the state. From the analysis of a total of 44 editorials related to forest fires from 1988 to 2017. By the using, in the forest fire-related editorials the social perceptions on forest fires are forest fire editorials categories, main keywords, contents of social perception on 'the main subject responsible for forest fire management,' 'forest fire prevention measures,' categorization, frequency analysis and context analysis of words used. It is found that in the first-period forest fire management measures were recognized as a part of the overall forest management. In the second period, the approaches of ecological management emerged on the part of forest fire management. As forest fires were managed as a type of social disaster during the third period, such perceptions were gradually reinforced that the state should protect the people from the forest fire. In the 3rd, 4th, and 5th National Forest Plan, the forest fire management policy of each period was focused in enlightening the general public, protecting forest resources ecosystems, and preventing loss of lives, respectively. As a result of the analysis of social perceptions and comparing them to the forest fire policies through the analysis of editorials on forest fires, it is found that the social perception on the forest fire and forest fire management plan has changed having interconnections.

A Study on the Bidding Trends of the Private Consignment Service of Landscape Management (조경관리 민간위탁용역의 입찰추이에 관한 연구)

  • Hwang, Dae-Jin;Kim, Dong-Pil;Moon, Ho-Gyeong
    • Journal of the Korean Institute of Landscape Architecture
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    • v.47 no.1
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    • pp.39-48
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    • 2019
  • Based on the bidding data of the national marketplace for public procurement service from 2003 to 2015, this study investigated and analyzed the bidding trends of the landscape management public consignment service by analyzing total bidding, type, client, region, license. The results are as follows. First, the total number of bids for civilian consignment services in landscape management increased by 1,112 cases, corresponding to a 487.7% increase over 10 years, and the total bidding amount increased by 144,504 million won, corresponding to a 382.5% increase. Second, in 10 years, the proportion of landscape management in landscaping works increased by 10%, and the bidding amount increased by 3%. Third, in the analysis of bidding trends by type, green areas showed the greatest growth in the number of bids, while the greenery of buildings showed the highest increase in the bid amount. Fourth, local autonomous entities, Gyeonggi province, and the landscaping planting construction industry showed the highest increase in the number of bids and the amount in each field such as client, region, and license. In summary, the number of cases and the bidding amount is increasing year by year. Considering the increasing number of users and demands thereof, the number of bids and the amount of consignment service for landscape management will continue to increase. The purpose of this study is to investigate and systematically analyze the tendency of bidding for 10 years for the private consignment service of landscape management in the current situation, where the importance of landscape management is increasingly emphasized. Another purpose of this study is to discern the necessity of the landscape management business and to provide the basis for incorporating the landscape management business into the professional construction industry in the future, thus providing opportunities for widening the expertise and diversity of the landscaping field. For the following study, the legal basis of landscape management, qualification, equipment standards, calculation of management cost per unit, and the appropriateness of the management cost should be considered.