• Title/Summary/Keyword: ecological systems

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Genetic Structure of the Neglected Decomposer, Ptecticus tenebrifer, with an Introduced Decomposer, Hermetia illucens

  • Jeong, Gilsang;Choi, Hansu;Kang, Hyejin;Jin, Seon Deok
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.2 no.2
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    • pp.96-100
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    • 2021
  • The era of mass production of agricultural and dairy systems inevitably causes a huge amount of biowastes during their processes. Modern consumption patterns of the general public also contribute to biowaste formation. Thus, processing biowastes has attracted much attention. The introduced black soldier fly (BSF) (Hermetia illucens) is considered as one of environmentally friendly management options for solving biowaste issues. However, an indigenous species, Ptecticus tenebrifer, is also a powerful decomposer that has been largely neglected. This species can be easily found on biowastes such as manure dump, agricultural wastes, and human food wastes. It can be also easily found in the field. It is even attracted to a food trap. To the best of our knowledge, this is the first ecological study on this species.

Development Needs and Direction of an Ecological Grading System of Korean Tidal Flats (한국 갯벌 생태 등급도의 개발 필요성과 방향)

  • Yoo, Jae-Won;Lee, Chang-Gun;Kho, Byung-Seol;Lee, Si-Wan;Han, Dong-Uk;Choi, Keun-Hyung;Kim, Chang-Soo;Hong, Jae-Sang
    • Ocean and Polar Research
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    • v.32 no.2
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    • pp.137-144
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    • 2010
  • There is a host of habitat assessment systems available to evaluate and grade tidal flat ecosystems in Korea. Nevertheless, we recognize the need to develop a better ecological scheme to improve reliability and accuracy given the importance of using an empirical approach in assigning grades to indicators and the limitation of current systems which evaluate tidal flats on a regional basis. A preferable system would be one that enables habitat mapping within a tidal flat, provides a diagnosis of ecological stress/health, has a high level of ecological relevance, communicability, and statistical robustness, and enables evaluation of diverse habitats within a tidal flat. The following points should be considered in framing such a system. Indicators should discriminate habitat quality into five to seven grades accomodating diverse characteristics and conservation value of a habitat, and the grading should be made from frequency distribution of indicators based on nationwide data.We suggest the following tasks in crafting such a system: i) The decision on selection of indicators should be made based on accuracy of assessment and practical application; ii) effects of physical habitat conditions on variability of indicators should be reflected; and, iii) further works on stress/health indicators should be addressed for adopting a multiple-indicator approach which reduces misdiagnosis.

Small Ruminants: Imperatives for Productivity Enhancement Improved Livelihoods and Rural Growth - A Review

  • Devendra, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1483-1496
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    • 2001
  • Small ruminants form an important economic and ecological niche in small farm systems and agriculture. Their current low level of contribution is dismal, and is not commensurate with the potential capacity for higher levels of production. The context for productivity enhancement and increased socio-economic contribution relates to large sizes of small ruminant populations; wide distribution across various agro-ecological zones and production systems; and diversity of breeds, where 66% of all goat and 57% of sheep breeds in Asia are found in China, India and Pakistan. The advantages and disadvantages of small ruminants over larger ruminants are enumerated with reference to adaptation and environment, small size, production systems and products and interactions with the environment. Discussion focuses especially on efficiency of meat production and niche markets for higher-priced goat meat, and inefficient marketing systems given an estimated 40-45% loss of income to farmers presently. Increasing the quantity of meat produced is related to live weight and the total number of animals at Slaughter, which in turn, depend on the total number of offsprings weaned and lifetime productivity. At the national level, priority attention is essential to build up numbers in concerted breeding programmes, selection for efficiency of reproduction and meat production, and improvements to make traditional markets and marketing systems to respond to the changing environmental and consumer preferences. Post-production systems are neglected and improvements are associated with collection, handling, marketing, slaughter facilities and consumer requirements. Potential opportunities to expand and benefit from integrating small ruminants into annual and perennial cropping systems remain largely unexplored. Important development imperatives include choice of species and better use of available breeds, appropriate production systems that match available feed resources, and linkages between production, products and by-products to markets. Affirmative action is necessary, backed by official policy support, institutional commitment and increased resource use, that can target poverty and directly benefit the poor, and shift subsistence production to a more market-oriented opportunity. These efforts together constitute the challenges for both the owners and producers of small ruminants in the immediate future, as also the will to accelerate increased productivity, improve their livelihoods and promote rural growth.

Sustainability of Olive Flounder Production by the Systems Ecology -II. Simulating the Future of Olive Flounder Aquaculture on the Land- (시스템 생태학적 접근법에 의한 넙치생산의 지속성 평가 -2. 넙치 육상양식산업에 대한 예측-)

  • Kim Nam Kook;Son Ji Ho;Kim Jin Lee;Cho Eun Il;Lee Suk Mo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.6
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    • pp.660-665
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    • 2002
  • In Korea, an olive flounder is very popular fish food item. However, due to the increasing human population, the present catches of the olive flounder may not be sufficient to satisfy the present demand. To increase the supply of the olive flounder, aquaculture has been begun. An interest in the aquaculture of the olive flounder has been increased recently because of its characteristics of good growth and high price in the market, However, the productivity of the olive flounder aquaculture depends on economic inputs such as fuels, facilities, and labor. The rapid growths of the olive flounder aquaculture and the concerns about economic and ecological sustainability have focused peoples attention on the aquaculture industry. In this study, an energy systems model was built to simulate the variation of sustainability on the aquaculture of olive flounder, The results of simulation based on calibration data in 1995 show that olive flounder production yield and asset slowly increase to steady state because of the law of supply and demand. The results of simulation based on the variation of oil price show that the more increase the oil price, the more decrease the olive flounder economic yield and asset. Energy sources required for systems determine the sustainability of systems. Conclusionally, the present systems of the olive flounder aquaculture should be transformed to ecological-recycling systems or ecological engineering systems which depend on renewable resources rather than aquaculture systems which depend on fossil fuels, and be harmonized with the fishing fisheries by the sustainable use of renewable resources in the carrying capacity.

Greenbelt Systems Play an Important Role in the Prevention of Landscape Degradation Due to Urbanization

  • Cho, Yong-Chan;Cho, Hyun-Je;Lee, Chang-Seok
    • Journal of Ecology and Environment
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    • v.32 no.3
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    • pp.207-215
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    • 2009
  • Greenbelts were designated by the Korean government in 1971 in 14 large cities to prevent uncontrolled urban expansion. Recently, deregulation of the greenbelt system has resulted in further development, but the ecological role of greenbelts has not been fully considered when decisions about urban management are being made. We examined the ecological roles of the greenbelt system in the Seoul metropolitan area and prepared sustainable management and improvement plans based on our analysis of landscape characteristics using satellite images covering a ${\sim}30$-year period. The loss of forest cover during this period in the greenbelt areas was lower than that in the areas outside and inside of the greenbelt. Fragmentation of forest cover was correlated with the pattern of loss of forest cover. The NDVI of the greenbelt remained steady at 90% of that in outside of the GB for three decades. This suggests that the greenbelt system has performed its primary roles well. However, the remaining green space was not adequate to provide a sink for air pollutants even when the greenbelt area was included. We discuss how the negative effects of urbanization can be reduced through sustainable management and restoration to promote ecological functioning in greenbelts and urban landscapes.

Current status and characteristics of the Ecological and Natural Map in the Republic of Korea

  • Eui-Jeong Ko;Hyosun Leem;Junghyun Lee;Wooseok Oh
    • Journal of Ecology and Environment
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    • v.48 no.1
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    • pp.8-16
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    • 2024
  • The integration and management of various national ecological assessments are essential for the benefit of the public. In the Republic of Korea, the Ecological and Natural Map (ENM) serves as a comprehensive platform that synthesizes the results of national ecosystem surveys into a unified system interface. To provide the current status and characteristics of our policy, we analyzed the ENMs and related appeals from 2014 to 2022. Following their implementation, the ENM Guidelines underwent nine revisions, with most of the revisions pertaining to appeals. Nine public announcements were made regarding the ENM, resulting in a gradual expansion of the conservation area. The data also showed a consistent increasing trend in appeals. Most of the 1st-grade areas in the ENM regions where appeals were filed have significantly decreased. The larger area or the smaller population density of an administrative distinct, the more appeals were filed. Our study presents information regarding the current status of the ENM system. The analysis of the operational direction and indicator trends across the 16-year period since the establishment of the system provides valuable insights for similar systems.

Review and Proposition of Biological Indicators for a New Ecological Grading System of Tidal Flats in Korea (한국의 갯벌 생태등급도 개발을 위한 생물학적 지시자의 검토와 제안)

  • Yoo, Jae-Won;Lee, Chang-Gun;Kho, Byung-Seol;Lee, Si-Wan;Han, Dong-Uk;Choi, Keun-Hyung;Kim, Chang-Soo;Hong, Jae-Sang
    • Ocean and Polar Research
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    • v.33 no.1
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    • pp.85-97
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    • 2011
  • The tidal flats of Korea today have reduced by 40% in size compared to 1964. To manage this important habitat properly, development of well-organized and nationwide-applicable grading systems is required. There have been several assessment systems proposed previously in Korea, but they are critically flawed in that selected biological indicators are not adequate and grading criteria are obscure and arbitrary. We reviewed the indicators used in these previous evaluation systems (e.g., diversity indices, quantity and quality of benthic macrofauna, halophytes, water birds, etc.) and subsequently proposed new indicators and an improved grading scheme. For the quantitative assessment of macrobenthic community, biomass reflecting production and ecosystem function is recommended over density, which is much less discriminatory among habitats. Of biodiversity indices used, within-, between-habitat and regional biodiversity indices that accurately reflect sampling efforts are suggested. In addition, we proposed to include species rarity, ecosystem engineers, and the ecological quality index ISEP (Inverse function of Shannon-Wiener Evenness Proportion). As for halophytes, their low spatial coverage on benthic habitat suggests that their presence can be used as an ecological indicator of benthic habitat, regardless of their protective status. We stress the need to introduce 1) quantile approach for quantitative indicators (e.g., diversity, biomass, etc.) in relation to grading, 2) presence-absence approach for spatial or aggregate indicators (e.g., boundaries of halophytes and feeding ground of water birds) and 3) benthic habitat mapping that combines all of these indicators.

Selection of Suitable Plants for Artificial Floating Islands - Comparisons of Vegetation Structure and Growth of Four Emergent Macrophytes (인공 식물섬에 적합한 식물의 선발 - 4종 정수식물의 식생구조와 생장의 비교)

  • Lee, Hyo Hye Mi;Kwon, Oh Byung;Suck, Jeong Hyun;Cho, Kang-Hyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.1
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    • pp.57-66
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    • 2001
  • The floating islands have been constructed for the water quality improvement and the biodiversity conservation in an disturbed aquatic ecosystem. We made floating islands consisted of a special float and substrates of coconut fibers implanted with four emergent macrophytes such as Phragmites australis, Zizania latifolia, Iris pseudoacorus, Typha angustifolia. Vegetation structure and plant growth were compared between on the floating islands and on ground in order to select suitable plants for the construction of floating islands. Emergent-macrophytic vegetation on the floating islands showed lower coverages and higher plant biodiversity due to natural introduction of various hydrophytes and hygrophytes. Shoot density was increased on floating islands except for Zizania latifolia. From the point of coverage and density of plants, Phragmites australis and Iris pseudoacorus were suitable for floating islands. Total biomass of emergent macrophytes was decreased on the floating islands. The belowground/aboveground biomass ratio of floating islands was higher than that of the ground. Out of planted macrophytes, Iris pseudoacorus with a high belowground/aboveground biomass ratio could be evaluated a suitable plant for the floating islands because a plenty of its root is profitable to adapt with the nutrient-limited environment of floating islands.

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