• Title/Summary/Keyword: Plant Settlement

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Plant Settlement Patterns and Their Effects on Breeding Sites of Little Terns (Sterna albifrons) on Sand Bars on Ganwol Lake

  • Nam, Jong-Min;Yoon, Ji-Hyun;Kim, Heung-Tae;Kim, Jae-Geun
    • Journal of Ecology and Environment
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    • v.31 no.1
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    • pp.37-43
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    • 2008
  • We analyzed soil characteristics, soil seed banks, and plant communities in a small islet in Ganwol Lake from May 2005 to August 2006 to examine the forces driving plant settlement on sand bars and the effects of plant settlement patterns on nesting sites of little terns (Sterna albifrons). The soil nutrients contents in a site where the feces of wintering birds accumulate (N: 15.4 mg/kg, P: 10.5 mg/kg, LOI: 0.51 %, pH: 6.8) and a site where organic sediments accumulate (N: 20.7 mg/kg, P: 16.4 mg/kg, LOI: 0.40%, pH: 6.6) were much higher those of a control site which was not affected by bird feces and organic sediments (N: 4.1 mg/kg, P: 5.4 mg/kg, LOI: 0.41%, pH: 6.7). However, a seed bank was formed only on the site with accumulated organic sediments. Plant settlement was accelerated by feces from wintering birds and organic sediment accumulation on sand bars in Ganwol Lake. The percentage of area disturbed by human activities increased from 0.2% in May 2005 to 13.9% in August 2006, and the percentage of annual communities increased from 27.5% to 43.3%, but the percentage of open area decreased from 55.2% to 28.0% from May 2005 to August 2006. These increases in disturbed area and annual communities decreased the open area for breeding of little terns. The enlargement of P. communis and T. angustata communities was suppressed by irregular flooding. These results provide useful information for the management of little tern breeding sites for conservation purposes.

Effect of Plant Life Cycle on Plant Settlement in Diverse Water Level (다양한 수위 조건에서 식물 생활형이 식물 정착에 미치는 영향)

  • Nam, Jong Min;Cho, Hyun Seung;Kim, Jae Geun
    • Journal of Wetlands Research
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    • v.17 no.1
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    • pp.19-25
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    • 2015
  • The purpose of this study is to reveal the effect of plant life cycle to plant settlement by 1 year monitoring. The subjects of monitoring are the plants (3 plant life cycle, 9 taxa) well established in the mesocosm. 18 mesocosms were divided into 3 sets and water levels were maintained at 0, 20 and 60 cm during 16 weeks from mid-May, respectively and at 0 cm except these 16 weeks. Height and population size of transplanted perennial plants (Scirpus tabernaemontani, Zizania caduciflora, Typha (Typha angustifolia and Typha orientalis)) at 1st year were not affected by diverse water level, though any more seedlings of these species were not settled at this condition. In contrast, water level condition strong influenced annual and biennial plant, relatively. As a result, timing and duration of flooding have great effect on successful settlement of annual and biennial plant without rhizome.

Study on financial effects resulted from modified settlement rules (CBP시장의 정산 규칙개정에 따른 양수발전의 재무적 영향 분석)

  • Lee, Jae-Gul;Yoon, Yong-Beum;Ahn, Nam-Sung
    • Proceedings of the KIEE Conference
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    • 2005.11b
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    • pp.177-179
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    • 2005
  • In Korean Power Market, Cost-based Bidding Pool is maintaining the present condition because restructuring of electricity industry is holding. When this market is designed, Settlement rules for Pumped-storage power plant made unfairly by other power plants. These rules were considered contribution of Pumped-storage power plant to network operation. by the way, there are some discussion about Settlement rules modification. so in this paper, we calculated financial effect of power plant by modified rules. And when we modify market rules, we can offer numerical information.

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Impacts of Energy Tax Reform on Electricity Prices and Tax Revenues by Power System Simulation (전력계통 모의를 통한 에너지세제 개편의 전력가격 및 조세수입에 대한 영향 연구)

  • Kim, Yoon Kyung;Park, Kwang Soo;Cho, Sungjin
    • Environmental and Resource Economics Review
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    • v.24 no.3
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    • pp.573-605
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    • 2015
  • This study proposed scenarios of tax reform regarding taxation on bituminous coal for power generation since July 2015 and July 2014, estimated its impact on SMP, settlement price, tax revenue from year 2015 to year 2029. These scenarios are compared with those of the standard scenario. To estimate them, the power system simulation was performed based on the government plan, such as demand supply program and the customized model to fit Korea's power system and operation. Imposing a tax on bituminous coal for power generation while maintaining tax neutrality reducing tax rate on LNG, the short-term SMP is lowered than the one of the standard scenario. Because the cost of nuclear power generation is still smaller than costs of other power generation, and the nuclear power generation rarely determines SMPs, the taxation impact on SMP is almost nonexistent. Thus it is difficult to slow down the electrification of energy consumption due to taxation of power plant bituminous coal in the short term, if SMP and settlement price is closely related. However, in the mid or long term, if the capacity of coal power plant is to be big enough, the taxation of power plant bituminous coal will increase SMP. Therefore, if the tax reform is made to impose on power plant bituminous coal in the short term, and if the tax rate on LNG is to be revised after implementing big enough new power plants using bituminous coal, the energy demand would be reduced by increasing electric charges through energy tax reform. Both imposing a tax on power plant bituminous coal and reducing tax rate on LNG increase settlement price, higher than the one of the standard scenario. In the mid or long term, the utilization of LNG complex power plants would be lower due to an expansion of generating plants, and thus, the tax rate on LNG would not affect on settlement price. Unlike to the impact on SMP, the taxation on nuclear power plants has increased settlement price due to the impact of settlement adjustment factor. The net impact of energy taxation will depend upon the level of offset between settlement price decrease by the expansion of energy supply and settlement price increase by imposing a tax on energy. Among taxable items, the tax on nuclear power plants will increase the most of additional tax revenue. Considering tax revenues in accordance with energy tax scenarios, the higher the tax rate on bituminous coal and nuclear power, the bigger the tax revenues.

Woody Plant Species Composition, Population Structure and Carbon Sequestration Potential of the A. senegal (L.) Willd Woodland Along a Distance Gradient in North-Western Tigray, Ethiopia

  • Birhane, Emiru;Gebreslassie, Hafte;Giday, Kidane;Teweldebirhan, Sarah;Hadgu, Kiros Meles
    • Journal of Forest and Environmental Science
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    • v.36 no.2
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    • pp.91-112
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    • 2020
  • In Ethiopia, dry land vegetation including the fairly intact lowland and western escarpment woodlands occupy the largest vegetation resource of the country. These forests play a central role in environmental regulation and socio-economic assets, yet they received less scientific attention than the moist forests. This study evaluated the woody plant species composition, population structure and carbon sequestration potential of the A. senegal woodland across three distance gradients from the settlements. A total of 45 sample quadrants were laid along a systematically established nine parallel transect lines to collect vegetation and soil data across distance gradients from settlement. Mature tree dry biomass with DBH>2.5 cm was estimated using allometric equations. A total of 41 woody plant species that belong to 20 families were recorded and A. senegal was the dominant species with 56.4 IVI value. Woody plant species diversity, density and richness were significantly higher in the distant plots compared to the nearest plots to settlement (p<0.05). The cumulative DBH class distribution of all individuals had showed an interrupted inverted J-shape population pattern. There were 19 species without seedlings, 15 species without saplings and 14 species without both seedlings and saplings. A significant above ground carbon (5.3 to 12.7 ton ha-1), root carbon (1.6 to 3.6 ton ha-1), soil organic carbon (35.6 to 44.5 ton ha-1), total carbon stock (42.5 to 60.7 ton ha-1) and total carbon dioxide equivalent (157.7 to 222.8 ton ha-1) was observed consistently with an increasing of distance from settlement (p<0.05). Distance from settlement had significant and positive correlation with species diversity and carbon stock at 0.64⁎⁎ and 0.78⁎⁎. Disturbance intensity may directly influence the variation of species composition, richness and density along the A. senegal woodland. The sustainability of the A. senegal woodland needs urgent protection, conservation and restoration.

A case Study on Application of Granular Compaction Pile in Fly Ash Landfill Area (Fly ash로 매립된 지역에서 쇄석다짐말뚝 적용에 관한 사례연구)

  • Lee, Jun-Eui;Lee, Seung-Joo;Hong, Jong-Chul;Lee, Jong-Young;Han, Jung-Geun
    • Journal of the Korean Geosynthetics Society
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    • v.18 no.3
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    • pp.1-9
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    • 2019
  • In this study, the effect of ground improvement was to be verified by granular compaction pile from the ground reclaimed with Fly Ash landfill site. The depth and strength parameters of the Fly ash layer was determined using the ground investigation and cone penetration test. And the STONE C program was used to predict the strength parameter, bearing capacity and settlement of the improved ground. As a result of the plate bearing test, the bearing capacity of improvement ground was higher than the design load and the settlement was smaller than the reference value. After the construction, the improvement effect by the cone penetration test was confirmed. The cone penetration resistance value($q_c$) increased by 250% to 500% and the effect was excellent.

A Study on Possibility of Sedimentation Basin Omission After Installed Membrane System in Drinking Water Treatment (정수처리시설에서 막공정 도입시 침전공정생략 가능성에 관한 연구)

  • Kim, Hyung-Sun;Zhoh, Choon-Koo;Hong, Seong-Ho;Kim, Sung-Jin;Lee, Kil-Sook
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.3
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    • pp.403-410
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    • 2006
  • The objective of this study was to evaluate the possibility of sedimentation basin omission when installed hybrid membrane filtration process in the field plant with the capacity of $500m^3/day$ for 11 months in the "G", water purification plant in Seoul. In order to evaluate the possibility of the sedimentation basin omission, we measured the change of DOC by coagulant dosage. Dosage of PAC(power activated carbon) 4mg/L and coagulant($AI_2O_3$ 10%) 1.67mg/L were compatible to meet the water quality. Also according to the experiment without settlement process, optimization G values were determined to be 300/s, 64/s, and 32/s at the mixing tank, the first flocculator and the second flocculator, respectively. The test was performed under the conditions PAC-coagulation-no settlement-MF. As a result, a dosage of 4.0mg/L as PAC and 0.86 to 1.22mg/L as $Al_2O_3$(10%) in the condition of flux of 62.5LMH were determined to keep TMP value less than $1.0kg_f/cm^2$.

Reinforcement of Building Foundation by the Low Slump Mortar Grout (저유동성 몰탈형 주입재에 의한 건물기초보강)

  • 천병식;고용일;권형석
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.71-76
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    • 2000
  • In generally, grouting consists of injecting a suspension or solution into the voids of soils. The low slump mortar grout has been used in America since 1950's. The Compaction Grouting, the injection of a very stiff under relatively high pressure, form a cylinderical grout support pile. The grout generally does not enter soil pores but remains in homogeneous mass that gives controlled displacement either to compact loose soils, or for lifting of structures, or both. In this paper, on the case of the reinforcement construction of 00 plant that the foundation's bearing capacity is insufficient and is to reinforce the foundation, a study has been peformed to analyze the effectiveness of the ground improvement. The bearing capacity of the Compaction Pile has been verified by the S.P.T and the settlement of the improved ground has been monitored rising the magnetic extensometer.

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