• Title/Summary/Keyword: Conservation Strategies

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A Study on the Optimal Distribution toss Management Using toss factor in Power Distribution Systems (분산형전원이 도입된 배전계통의 손실산정기법에 관한 연구)

  • Rho Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.3
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    • pp.231-240
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    • 2005
  • Recently, the needs and concerns for the power loss are increasing according to the energy conservation at the level of the national policies and power utilities's business strategies. Especially, the issue of the power loss is the main factor for the determining the electric pricing rates in the circumstances of the deregulation of electrical industry. However, because of the lacking of management for power loss load factors (LLF) it is difficult to make a calculation for the power loss and to make a decision for the electric rates. And loss factor (k-factor) in korea, which is a most important factor for calculation of the distribution power loss, has been used as a fixed value of 0.32 since the fiscal year 1973, There(ore, this study presents the statistical calculation methods of the loss factors classified by load types and seasons by using the practical data of 65 primary feeders which are selected by proper procedures. Based on the above the algorithms and methods, the optimal method of the distribution loss management classified by facilities such as primary feeders, distribution transformers and secondary feeders is presented. The simulation results show the effectiveness and usefulness of the proposed methods.

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Ecology and Early Life History of Endangered Freshwater Fish, Pseudobagrus brevicorpus (Pisces: Bagridae) (꼬치동자개(Pseudobagrus brevicorpus)의 생태와 초기 생활사)

  • Kang, Eon-Jong;Yang, Hyun;Lee, Heung-Heon;Cho, Yong-Cheol;Kim, Eung-Oh;Lim, Sang-Gu;Bang, In-Chul
    • Korean Journal of Environmental Biology
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    • v.25 no.4
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    • pp.378-384
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    • 2007
  • Some of ecological factors and the early life history of endangered freshwater fish, Pseusobagrus brevicorpus, were investigated to proliferate artificially and to restore the population by release seedlings. The density of population in restricted area by small scale dam was 1.25 ind. $m^{-2}$, and the low capacity for reproduction having 200$\sim$250 eggs ind$^{-1}$. were thought to be a reason of this endangered situation. From the result of induction of natural spawning in aquarium after hormone injection it was considered that the spawning substrate would be aquatic plants with slender branches. The hatching was observed after 50 hrs after fertilization and the larvae showed aggressive behavior. Yolk was almost absorbed 3 days after hatching, and the larvae shaped tad-pole grew up to fry after 30 days. We discussed on the strategies for conservation of this species according to those results from investigation on ecology and early life history.

Development of Strategic Environment Assessment Model in Urban Development Plan - In case of Metropolitan Plan - (도시개발 행정계획의 전략환경평가 모델개발 - 광역도시계획에의 사례적용 -)

  • Choi, Hee-Sun;Song, Young-Il
    • Journal of Environmental Impact Assessment
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    • v.19 no.4
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    • pp.381-396
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    • 2010
  • It is essential to consider strategies, spatial planning, and reflection of sustainability for the creation of sound urban spaces. To this end, there is a need for plans that can secure better sustainability through strategic environmental assessment (SEA) of plans. This study examined the literature and available precedent to develop a SEA model for administrative plans for urban development including metropolitan plans, urban master plans and urban management plans. In the course of development of the model, environmental issues associated with the urban plans were analyzed by classifying them into ten categories, including "spatial planning," "conservation planning," "greenbelt systems," "habitats." and etc. according to their rank. Furthermore, those issues were reflected on the development of environmental evaluation indices for the plans. Overall and detailed environmental indices that can be applied to the administrative plans for urban development including metropolitan plans, urban master plans and urban management plans were devised for five stages: (1) Establishment of development goals and strategy, (2) Analysis of current status and characteristics, (3) Conceptualization of spatial structure, (4) Planning for each department, and (5) Execution and management. Sub plans are more detailed and concrete. Criteria based on the evaluation indices, when performing evaluations on plans based on each environmental assessment index in reference to experts and the literature, were used to forecast their effects, i.e. whether they had a positive, negative, or no effect or relationship, or whether their effects was uncertain. Based on the forecasts, this study then presents means to establish more improvable plans. Furthermore, by synthesis of the effects according to each index and integration of the process, plans were analyzed overall. This study reflects the characteristics of the present time period based on issues in the SEA process and techniques in upper level administrative plans being newly established, and presents them according to the stage of each plan. Furthermore, by forecasting the effect of plans by stage, this study presents proposals for improvement, and in this aspect, can be meaningful in promoting plan improvements through SEA.

A Time-Series Analysis of Landscape Structural Changes using the Spatial Autocorrelation Method - Focusing on Namyangju Area - (공간자기상관분석을 통한 시계열적 경관구조의 변화 분석 - 남양주지역을 대상으로 -)

  • Kim, Heeju;Oh, Kyushik;Lee, Dongkun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.3
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    • pp.1-14
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    • 2011
  • In order to determine temporal changes of the urban landscape, interdependence and interaction among geo-spatial objects can be analyzed using GIS analytic methods. In this study, to investigate changes in the landscape structure of the Namyangju area, the size and shape of landscape patches, and the distance between the patches were analyzed with the Spatial Autocorrelation Method. In addition, both global and local spatial autocorrelation analyses were conducted. The results of global Moran's I revealed that both patch size and shape index transformed to a more dispersed pattern over time. Next, the local Moran's I of patch size in all time series determined that almost all patches were of a high-low pattern. Meanwhile, the local Moran's I of the shape index was found to have changed from a high-high pattern to a high-low pattern in time series. Finally, as time passes, the number of hot spot patches about size and shape index had been decreased according to the results of hot spot analysis. These changes appeared around the development projects in the study area. From the results of this study, degradation of landscape patches in Namyangju were ascertained and their specific areas were delineated. Such results can be used as useful data in selecting areas for conservation and for preparing plans and strategies in environmental restoration.

The Value of Ecosystem Services based on Land Use in Shinangun, Jeonnam, Korea (전남 신안군의 토지이용에 따른 생태계서비스 가치와 지속가능한 활용방안)

  • Kim, Jae-Eun
    • Korean Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.202-213
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    • 2014
  • More than half of all the tidal flats and islands in South Korea are located in Jeonnam. Shinangun accounts for a large amount of these tidal flats and island. This study assessed the value of ecosystem services for 14 administrative units (2 'eup' and 12 'myeon') that have around 1,000 islands in Shinangun, using the method described by Costanza et al. (1997). The assessment involved examining the land use types in Shinangun in relation to ecosystem services value. The finding showed that the tidal flat areas had the highest value of ecosystem services in most of the islands of Shinangun, in particular in Aphae-eup and Jido-eup. The study illustrates how quantitative analysis of land use patterns can help local governments like Shinangun to formulate policy for conservation and sustainaable use of ecosystem services. Especially, tidal flat areas are unique and fragile ecosystem, so it is very importat to make strategies for sustainable development in bioculturally diverse areas. Some suggestions regarding landscape planning in Shinangun are provided.

Estimating Habitat Carrying Capacity of Shorebirds in the Intertidal Mudflat (조간대 갯벌에서의 도요·물떼새 서식지수용능력 추정)

  • Moon, Young-Min;Kim, Kwanmok;Yoo, Jeong-Chil
    • Ocean and Polar Research
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    • v.42 no.1
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    • pp.21-31
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    • 2020
  • Shorebirds migrating along the East Asian-Australasian Flyway (EAAF) have been drastically decreasing due to continuous area loss and quality degradation of intertidal mudflats in the Yellow Sea. Evaluating the current habitat quality by means of habitat carrying capacity estimation could be effective in predicting the magnitude of impacts caused by habitat loss and provide better understanding to improve management strategies. In this study, we estimated the total biomass of Macrophthalmus japonicus, a main prey item of curlews in the Korea peninsular as habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island, one of the key stopover sites for curlews in the EAAF. The result of the estimation took into account spatial differences of prey biomass and the available foraging time by tide patterns. Accordingly, it was found that curlew populations account for 30.26% of the habitat carrying capacity. When we calculated the mean biomass of the area and extrapolated it to the whole area to calculate the total biomass, it was found that the curlews have consumed 10.92% of the total biomass. The results show that the habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island has decreased by 7.8% compared to a study conducted twenty years ago employing the same method. This study shows that there can be considerable differences in the results of habitat carrying capacity estimation between different methods, indicating that various environmental factors that affect the estimation results of habitat carrying capacity must be considered to achieve a more precise analysis and assessment.

Potentials of and Threats to Traditional Institutions for Community Based Biodiversity Management in Dryland Areas of Lower Moshi, Tanzania

  • Woiso, Dino Andrew;Shemdoe, Riziki Silas;Kayeye, Heri
    • Journal of Forest and Environmental Science
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    • v.25 no.3
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    • pp.177-185
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    • 2009
  • Dryland species and ecosystems have developed unique strategies to cope with low and sporadic rainfall. They are highly resilient and recover quickly from prevailing disturbances such as fires, herbivore pressure and drought. Dryland people have engineered pastoral and farming systems, which are adapted to these conditions and have sustained the livelihoods of dryland people for centuries. In this article, we present the status of potentials and threats to dryland biodiversity and explore options for its conservation and sustainable use. Findings of the research can be summarized as follows: (i) The ecosystem goods and services are highly valued by the community but mechanism for wise use of the resources has disappeared, (ii) forests are under the ownership of the government but the local community is the realistic custodian of the forests through village leaderships and environmental committees; (iii) the immediate major threat to dryland biodiversity held in the forests appears to be the degradation of ecosystems and habitats caused by new and powerful forces of environmental degradation such as large scale irrigation of rice farms, poverty-induced overexploitation of natural resources, and disappearance and ignorance of traditional institutions for management of dryland biodiversity. These new forms of disturbances often overpower the legendary resilience of dryland ecosystems and constitute potentially serious threats to dryland biodiversity. Forests, wetlands and oases all of which are micro hot spots of dryland biodiversity, appear to be particularly vulnerable hence the need to set up some rules and regulations for sustainable utilization of these resources.

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Biotic and spatial factors potentially explain the susceptibility of forests to direct hurricane damage

  • Kim, Daehyun;Millington, Andrew C.;Lafon, Charles W.
    • Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.364-375
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    • 2019
  • Background: Ecologists continue to investigate the factors that potentially affect the pattern and magnitude of tree damage during catastrophic windstorms in forests. However, there still is a paucity of research on which trees are more vulnerable to direct damage by winds rather than being knocked down by the fall of another tree. We evaluated this question in a mixed hardwood-softwood forest within the Big Thicket National Preserve (BTNP) of southeast Texas, USA, which was substantially impacted by Hurricane Rita in September 2005. Results: We showed that multiple factors, including tree height, shade-tolerance, height-to-diameter ratio, and neighborhood density (i.e., pre-Rita stem distribution) significantly explained the susceptibility of trees to direct storm damage. We also found that no single factor had pervasive importance over the others and, instead, that all factors were tightly intertwined in a complex way, such that they often complemented each other, and that they contributed simultaneously to the overall susceptibility to and patterns of windstorm damage in the BTNP. Conclusions: Directly damaged trees greatly influence the forest by causing secondary damage to other trees. We propose that directly and indirectly damaged (or susceptible) trees should be considered separately when assessing or predicting the impact of windstorms on a forest ecosystem; to better predict the pathways of community structure reorganization and guide forest management and conservation practices. Forest managers are recommended to adopt a holistic view that considers and combines various components of the forest ecosystem when establishing strategies for mitigating the impact of catastrophic winds.

A Study on the Temporal Change of Soil Loss of Kyungan River Basin with GIS (토지이용변화에 따른 경안천 유역 토양유실에 관한 연구)

  • 김상욱;박종화
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 1995.12a
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    • pp.22-32
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    • 1995
  • The purpose of this study is to estimate not only the watershed soil loss but also its temporal changes of Kyungan River basin, the study area, due to the land development. To analyze the soil loss of the river basin, USLE was employed. GIS and remote sensing were also utilized to estimate the soil loss. The data for this analysis consist of a series of thematic map and remotely sensed data. The remotely sensed images for this study are Landsat TM(Oct, 28, 1997 & Sep. 22, 1992), In Kyungan River basin, not only the detection of temporal changes of land use and GVI, but also the estimation of soil loss provided very significant factors that affect to the watershed environment quality. The management of the factors of vegetative cover, slope steepness and length were the keys to reduce soil loss and solve conservation and protection issues of Kyungan River basin. GIS application with USLE to the watershed analysis allows the planner to recognize sensitive sites and to plan strategies to minimize soil loss.

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Development of EST-SSRs and Assessment of Genetic Diversity in Little Millet (Panicum sumatrense) Germplasm

  • Ali, Asjad;Choi, Yu-Mi;Hyun, Do-Yoon;Lee, Sukyeung;Kim, Jin-Hee;Oh, Sejong;Lee, Myung Chul
    • Korean Journal of Plant Resources
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    • v.30 no.3
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    • pp.287-297
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    • 2017
  • Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. In this study, a total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST-SSR markers were developed based on the trials of transferability of these primers in little millet. The EST-SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. The average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. The polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST-SSR markers in assessing genomic relationships in little millet. The findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.