• Title/Summary/Keyword: ecological systems

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Comparative assessment of age, growth and food habit of the black-chinned tilapia, Sarotherodon melanotheron (Rüppell, 1852), from a closed and open lagoon, Ghana

  • Zuh, Cephas Kwesi;Abobi, Seth Mensah;Campion, Benjamin Betey
    • Fisheries and Aquatic Sciences
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    • v.22 no.12
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    • pp.31.1-31.12
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    • 2019
  • Background: The black-chinned tilapia, Sarotherodon melanotheron, is the most abundant fish species in the Nakwa (an open lagoon) and Brenu (a closed lagoon) in the Central Region of Ghana. Aspects of the life history characteristics and the ecology of the fish populations in both lagoons were studied to assess the bio-ecological status of this important resource. Methods: Fish samples were obtained from fishermen that fish on the Nakwa and Brenu lagoons using cast, drag and gill nets. The age of the fish was assessed from otoliths analysis and its growth modelled following the von Bertalanffy growth function. Morphometric characteristics of the fish populations were analysed using power regression and ANOVA for parameters comparisons, and Student's t test to determine whether species grew isometrically. The percentage occurrence method was used to analyse the stomach contents of the fish. Results: A total of 382 fish samples from both lagoons were measured, comprising 209 from Nakwa lagoon and 176 from Brenu lagoon. The size and weight of fish samples ranged between 3.9-11.5 cm total length and 1.0-27.3 g for Nakwa Lagoon and 5.6-12.8 cm total length and 3.2-29.8 g for the Brenu Lagoon. The estimated von Bertalanffy growth parameters were L∞ = 12.04 cm and K = 2.76/year for the Nakwa Lagoon samples and L∞ = 13.44 cm and K = 3.27/year for Brenu Lagoon samples. Daily otolith incremental rate ranged from 0.01-0.03 mm per day to 0.01-0.02 mm per day for Nakwa and Brenu lagoons, respectively. Stomach content analysis of the fish samples revealed that the species are planktivorous and the range of food varied between the lagoons. Green algae were the most prevalent food item in the stomachs of the fish samples from Nakwa with the frequency of 69% whilst diatoms (80.5%) were most prevalent phytoplanktonic food item for the fish in Brenu lagoon. Conclusions: The estimates of asymptotic length for the species in both lagoons are close to known values of the species length at first sexual maturity and points to intensive fishing pressure. As a consequence, a comprehensive sample-based survey is required in both lagoons to derive estimates of management reference points. The results of the stomach content analysis are beneficial to the construction of diet matrix for ecosystem models of the two systems.

Effects of Consumer Awareness of Organic Agricultural Products on Repurchase Intention (유기농산물 소비자인식이 재구매의사에 미치는 영향)

  • Seo, Yong-Sil;Seo, Yoon-Jeong;Lee, Jin-Hong;Lee, Byung-Oh
    • Journal of Distribution Science
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    • v.13 no.11
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    • pp.59-67
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    • 2015
  • Purpose - The number of consumers adopting a lifestyle of health and sustainability has recently increased with the rise of trends in healthy living. The size of the organic agricultural product market has also increased given that these consumers prefer consuming environmentally friendly products that promote family health. However, awareness of organic agricultural products remains insufficient because of the characteristics of the Korean organic agriculture system, which only focuses on food safety inspection. The object of this research is to suggest a policy approach to increase understanding and to expand the purchasing of organic agricultural products by analyzing the influence of customer recognition of such products on their willingness to repurchase. Research design, data, and methodology - This study used binomial logistic regression analysis with the aim of explaining the effects of consumers' socio-demographic characteristics, their awareness of the equivalence arrangement for organic food and of the abolishment of low-pesticide agricultural product certification, and their viewing of negative broadcasts about organic agricultural products on their repurchase intention of such products. A questionnaire survey was conducted with 655 respondents who were in their 20s, lived either in Seoul or in its metropolitan area, and had purchased organic agricultural products. Result - From the results of the analysis, the majority of the respondents recognized organic agricultural products, but they found their prices to be expensive. The majority of the respondents were also aware of the certification system and the reliability of organic agricultural products. However, the results indicate that efforts need to be made to recover consumer trust as many respondents stated that their trust levels in these products were low. In general, those purchasing organic agricultural products were satisfied, but those answering "very satisfied" were not in the majority. Binomial logistic regression analysis results revealed that repurchase intention decreased as consumers viewed a greater number of negative broadcasts about these products. On the other hand, repurchase intention increased as they became more aware of the abolishment of low-pesticide certification. Repurchase intention also increased as income increased, as the number of family members decreased, and when a consumer was a member of a consumer organization. In addition, the older the consumers were who watched the TV programs, the smaller the number of family members that were aware of the abolishment of low-pesticide agricultural product certification and, the higher the income of the consumers aware of organic equivalence arrangement, the greater their repurchase intention. Conclusion - External stimuli, such as negative TV programs on organic agricultural products and the abolishment of the low-pesticide agricultural product certification, relevant social issues and systems, influence consumer repurchase intention. To that end, positive environmental and ecological broadcasting about organic agricultural products would contribute to an increase in purchasing. Additionally, this could be used for promotion and marketing plans as the results indicate that trust in organic agricultural products would cause a positive repurchasing effect.

Effect of Methylobacterium oryzae CBMB20 Inoculation and Methanol Spray on Growth of Red Pepper (Capsicum annuum L.) at Different Fertilizer levels (메탄올 살포와 Methylobacterium oryzae CBMB20 접종이 고추의 생육이 미치는 영향)

  • Chauhan, Puneet Singh;Lee, Gil-Seung;Lee, Min-Kyoung;Yim, Woo-Jong;Lee, Gyeong-Ja;Kim, Young-Sang;Chung, Jong-Bae;Sa, Tong-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.4
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    • pp.514-521
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    • 2010
  • Fertilizers, plant growth promoting microbes and plant growth regulators should be combined together and used in order to achieve a maximal plant growth and yield in modern sustainable and ecological agricultural systems. In this study rhizosphere inoculation of Methylobacterium oryzae CBMB20 and foliar application of methanol were tested for their ability to promote the growth of red pepper plant at different levels of organic fertilizer. Rhizosphere inoculation of M. oryzae CBMB20 and foliar spray of methanol could promote red pepper plant growth and yield, and the growth promoting effect induced by the combined treatment of M. oryzae CBMB20 inoculation and foliar spray of methanol was more distinctive. This result suggests that a synergistic growth promoting effect of methanol spray and M. oryzae CBMB20 inoculation can be obtained in the combined treatment of the two growth promoting factors. The growth promoting effect was more significant in the lower fertilization rate, and the plant growth was not significantly different between 100 and 300% fertilizer treatments where both M. oryzae CBMB20 inoculation and foliar spray of methanol were included. This result indicates that, with the plant growth promoting effect of M. oryzae CBMB20 and methanol, fertilizer application rate can be profoundly reduced without any significant decreases in biomass accumulation and yield of crops.

An Aesthetic Interpretation of Post-industrial Parks with a Perspective of the Sublime (숭고의 개념에 기초한 포스트 인더스트리얼 공원의 미학적 해석)

  • Lee, Myeong-Jun;Pae, Jeong-Hann
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.4
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    • pp.78-89
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    • 2012
  • This study aimed to interpret aesthetic properties of post-industrial parks with a perspective of the sublime. It examined the roles of the sublime related to landscape architectural history and traced aesthetic characteristics of post-industrial parks based on aesthetic issues of the sublime. In the history of landscape architecture, the sublime had expanded the scope of aesthetic enjoyment. It had operated as an alternative aesthetic category against conventional landscape design. At the same time, it had been associated with the original role of landscape architecture, which created artworks by taming wild and terrible qualities of wilderness or brown field. This study discovered sublime characteristics of post-industrial parks, inquiring into the relationship between the aged industrial infrastructures and wild plants. First, the sense of industrial structure and the sense of plants have conflict dialectically, constructing an aesthetic field of unique sensory experiences. Second, the dialectical relationship produced an uncertainty in time so that people can experience the complexity of time. Third, post-industrial parks proposed an alternative view of nature. Post-industrial parks presented healing power to restore contaminated land through ecological design strategy so that people can find the quality of wilderness in the brown field of urban landscape. As a result, an aesthetic experience of post-industrial parks produced a sublime impression.

Korean Secondary School Teachers' Professionalism in Teaching Environmental Subjects (중등교사들의 환경교육 수업에 대한 교사 전문성 분석)

  • Son, Yeon-A;Myeong, Soo-Jeong;Choi, Don-Hyung;Min, Byeong-Mee;Kim, Kyoung-Ran
    • Hwankyungkyoyuk
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    • v.22 no.2
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    • pp.43-55
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    • 2009
  • The objective of this study is to find out the professionalism of secondary school teachers in teaching environmental subjects. This research was conducted using a questionnaire survey of 431 secondary school teachers from 34 schools in Seoul and Gyeonggi Province, Korea. A 5-point Likert scale self-evaluation questionnaire on their professionalism in environmental education was developed based on Hungerford et al.'s (1994) evaluation criteria. Two middle school teachers' classes were observed, and video taping and interviewing were also conducted. The survey analysis revealed that teachers evaluated their professionalism on environmental subjects to be a little above the middle of the scale. The mean values were 2.80 for the foundation level; 2.86 for the conceptual awareness level; 2.84 for the investigation level; 2.94 for the environmental action skills level; and 2.84 for the educational application level. However, class observations revealed that there was some gap between their self-evaluation of professionalism and their actual classroom application. Both classes were not that satisfactory with regard to 'the abilities to communicate and apply ecological concepts', 'the ability to clarify the roles of different value systems for environmental issues and personal values in decision making', 'the ability to clarify their own value system regarding solutions to environmental issues', and 'the ability to apply citizen action skills for solving environmental issues and for sustainable development'. The results provide a basic reference for the improvement of environmental-related education.

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Evaluating and Improving Urban Resilience to Climate Change in Local Government: Focused on Suwon (기초지자체 기후변화 대응을 위한 도시회복력 평가 및 증진방안: 수원시를 대상으로)

  • Kim, Eunyoung;Jung, Kyungmin;Song, Wonkyong
    • Journal of Environmental Impact Assessment
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    • v.27 no.4
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    • pp.335-344
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    • 2018
  • As the damage caused by the abnormal climate due to climate change is increasing, the interest in resilience is increasing as a countermeasure to this. In this study, the resilience of Suwon city was examined and the plan to improve the resilience were derived against climate impacts such as drought, heatwave, and heavy rain. Urban resilience is divided into social resilience (e.g. vulnerable groups, access to health services, and training of human resources), economic resilience (e.g. housing stability, employment stability, income equality, and economic diversity), urban infrastructure resilience (e.g.residential vulnerability, capacity to accommodate victims, and sewage systems), and ecological resilience (e.g. protection resources, sustainability, and risk exposure). The study evaluated the urban resilience according to the selected indicators in local level. In this study, the planning elements to increase the resilience in the urban dimension were derived and suggested the applicability. To be a resilient city, the concept and value of resilience should be included in urban policy and planning. It is critical to monitor and evaluate the process made by the actions in order to continuously adjust the plans.

Opportunities and Challenges for Multi-Level-Stakeholder Participation in Community-Based Ecotourism Development: The Case of the Boabeng-Fiema Monkey Sanctuary, Ghana (지역사회 기반 생태관광 개발에서 다양한 이해 관계자들의 참여 기회와 도전: 가나 Boabeng-Fiema 원숭이 보호구역 사례를 중심으로)

  • Owusu, Victor;Boafo, Yaw Agyeman
    • Journal of the Economic Geographical Society of Korea
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    • v.21 no.1
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    • pp.53-68
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    • 2018
  • Community-based ecotourism (CBE), if well-developed can be a practical approach for promoting socio-economic well-being and sustaining ecological resources. The growth and its development worldwide especially in developing economies is a welcome development. The study aimed at assessing the Boabeng-Fiema Monkey Sanctuary in Ghana, as an example of traditional conservation system of management that has ensured greater community participation, equity, inclusiveness, and multi-level stakeholder partnership. In-depth interviews with key informants and documentary analysis of relevant peer reviewed and grey literature were the main qualitative data collection used. Results revealed that majority of the interviewees support and value the current system of traditional management. The enforcement of rules and regulations and other cultural and religious practices were discussed by key informants. Opportunities for multiple livelihood strategies as a result of the CBE is seen as critical for increasing local's acceptance and participation. The remarkable growth of the sanctuary, as well as the increase in human population, has created a shortage of land for domestic and other commercial purposes which is identified as posing a major challenge to the sustenance of the sanctuary. The study recommends diversification of livelihood opportunities presented by the presence of the sanctuary like the introduction of homestay concept, craft making- wood carving, painting, artisan shops.

Age and life history of an old black pine (Pinus thunbergii Parl.) tree at Cave Temple on Mt. Sanbangsan, Jeju Island, Korea, died due to pine wilt disease in 2013

  • Kim, Eun-Shik;Lee, So-Hee;Kim, Joon-Bum;Kim, Chan-Soo;Yoon, Bong-Taek;Lee, Sung-Hoon;Lim, Wontaek;Kim, Hyojung;Choi, Junghwan;Han, Hyerim
    • Journal of Ecology and Environment
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    • v.38 no.1
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    • pp.85-93
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    • 2015
  • In 2013, the epidemics of pine wilt disease caused by the pine wood nematodes (Bursaphelenchus xylophilus) resulted in damages to the forests of black pine (Pinus thunbergii Parl.) trees in Jeju Island, Korea. Among the affected trees, an old black pine tree at Cave Temple on Mt. Sanbangsan was included and died due to the prevalence of pine wilt disease. The tree was on Mt. Sanbangsan, which was designated as a National Scenic Place with the Number 77 and was believed to be more than 400 years old in age. By examining the disc of the tree stem obtained from the height of 2 m, we counted the tree rings from 4 different directions and cross-dated the readings by comparing the records of drought simulated from the BROOK Model. Our analysis indicates that the tree seems to have grown since late 1860s. Contrary to the belief of the general public, we can conclude that the age of the tree was estimated to be at maximum 150 years, which means that it was not the same old tree as was shown in the painting of the Tam-Ra-Sun-Ryeok-Do (an old painting book for the Inspection Tour of Jeju Island) published in 1702. Discussion was extended to the life history of the tree in growth and leaning and the measures to protect the tree species from the damages of the pine wilt disease caused by pine wood nematodes.

Change of Ripened Persimmon Vinegar with Mountain Ginseng Ingestion on Energy Metabolism in Rats (산양삼 혼입 숙성 감식초 섭취에 의한 흰쥐의 에너지 대사 변화 연구)

  • Jeon, Byung-Duk;Kim, Pan-Gi;Ryu, Sungpil
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.517-525
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    • 2012
  • In this study, a 4-year-old mountain ginseng was mixed and ripened with 4-year-matured persimmon vinegar, and then it was diluted 5 times and orally administerd to rats. Afterwards, by analyzing the protein expression rate which affects both the carbohydrate metabolism and the lipid metabolism, this study examined the anti-obesity effect of the fusion material. The rats were divided into a control group (CON), a persimmon vinegar group (PV) and a mountain ginseng+persimmon vinegar fusion material group (MPV). The weight gain rate was found to be low in PV and MPV, and the concentration of glucose was also low in PV and MPV. However, GLUT-2 was found to be significantly high in these two groups on the contrary. Both the concentration of free fatty acid and CPT-1 protein expression rate were high in PV and MVP, but MVP was higher than PV. Cytochrome C oxidase was found to be higher in MPV than in CON. AMPK, $PPAR-{\gamma}$ and $PGC1-{\alpha}$ were all high in PV and MPV, but MPV was higher than PV. All the results above verified the thermogenesis effect of the fusion material, leading to an increase of energy metabolism, and it was thought that the fusion material could be effectively used for anti-obesity. However, it seems necessary to verify the anti-obesity effect through various further studies.

Rhus verniciflua Extract Ingestion and Exercise Training on Blood Lipids and Insulin Resistance in Rats (옻나무 추출액 섭취와 운동훈련이 흰쥐의 혈중 지질 및 인슐린 저항성에 미치는 영향)

  • Lee, Youn-Kyung;Lee, Soo-Chun;Jeon, Byung-Duk;Kim, Sea-Hyun;Kim, Pan-Gi;Ryu, Sungpil
    • Journal of Korean Society of Forest Science
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    • v.98 no.6
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    • pp.681-689
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    • 2009
  • We investigated the effect of Rhus verniciflua Stokes extract ingestion with exercise training on plasma lipids and insulin resistance for 8 weeks. Forty SD (Sprague-Dawley) male rats were used as the experimental animals that were divided into CON (control), RVS (Rhus verniciflua Stokes), EXE (exercise training), and RVS-EXE (Rhus verniciflua Stokes with exercise training), respectively. Body weight gain in EXE (202%) and RVS-EXE (203%) was significantly lower than CON (253%) and RVS (239). Stored fats were significantly lower with RVS and/or exercise training. Blood lipids were enhanced in RVS and RVS-EXE compared to CON. Blood glucose was significantly high in CON compared to the other groups. Insulin and HOMA index has the same tendencies with glucose, however, the synergic effect was found in RVS-EXE. In conclusion, Rhus verniciflua Stokes extract ingestion with exercise training has the effect of lowering amount of stored fats, reducing blood lipids, and enhancing insulin resistance, therefore, metabolic syndrome, diabetes, obesity, and hyperlipidemia might be prevented.