• Title/Summary/Keyword: Large Slope

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Planting Method of Buffer Green Space in the Reclaimed Seaside Areas, Rokko Island, Kobe, Japan (일본 고베시(신호시(神戶市)) 로코(육갑(六甲))아일랜드 임해매립지의 완충녹지 식재기법 연구)

  • Han, Bong-Ho;Kim, Jong-Yup;Choi, Jin-Woo;Cho, Yong-Hyeon
    • Korean Journal of Environment and Ecology
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    • v.24 no.2
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    • pp.157-165
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    • 2010
  • This study was carried out to suggest the basic data of planting method for construction of buffer green space based on the land use in case of reclaimed land by analyzing land structure, planting concept, and planting structure in buffer green space, Rokko Island, Kobe, Japan. Rokko Island(total area: 580ha) is divided into port and logistics industry area and urban area by constructing the box type large-scale buffer green space. The land structure of buffer green space were biased mounding type, parallel mounding type, and complex mounding type. The width of buffer green space was 50meters in case of northern area, from 28 to 32meters in case of eastern area, and 37.5meters in case of western area, and the slope of that was from 18 to 25 degrees and the height of that was from 2 to 15meters. There were applied landscape and buffer planting concept on the sea side area of northern buffer green space, on the other hand landscape and shade planting concept on the Inner city side area of that. According to the result of planting structure analysis of northern buffer green space, the main woody species were those of deciduous-evergreen species grow in warm-temperate forest zone such as Quercus glauca, Cinnamomum camphora, Machilus thunbergii, Elaeagnus maritima. The results of maximum number of species and planting density by $100mm^2$ was that 9 species 22 individuals in canopy layer, 9 species 15 individuals in understory layer, 3 species 67 individuals in shrub layer, and 14 species 104 individuals in total. The plant coverage of northern buffer green space based on the ecological planting method was from 69 to 139% in case of canopy layer, from 26 to 38% in case of understory layer, from 6 to 7% in case of shrub layer, and from 101 to 184% in total. Index of plant crown volume of northern buffer green space based on the ecological planting method was from 1.40 to $3.12m^3/m^2$ in case of canopy layer, from 0.43 to $0.55m^3/m^2$ in case of understory layer, $0.06m^3/m^2$ in case of shrub layer, and from 1.89 to $3.73m^3/m^2$ in total.

Studies on Soil Conservation Effects of the Straw-mat Mulching (III) -Effects of the Mat Structures and Its Practicality- (볏짚거적덮기공법(工法)의 사방효과(砂防效果)에 관(關)한 연구(硏究)(III) -거적 밀도(密度)의 영향(影響) 및 공법(工法)의 실용성(實用性)-)

  • Woo, Bo-Myeong
    • Journal of Korean Society of Forest Science
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    • v.27 no.1
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    • pp.5-14
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    • 1975
  • Eroded sloping faces in hillsides including cut-bank slopes are liable to both surface erosion and land-slides and the key to control of these form of erosion lies with drainages of excessive run-off and dense vegetation establishment including surface mulching on the slopes. Micro-plots having $1.6m^2$ (1 metre in width and 1.6 metres in slope length, and 1:1.2 in gradient) of banking slopes on coarse sand soil are used to establish the order of magnititude of the difference in controlling of soil erosion and water runoff, and in rating of survival, performed on the repetetions of three-experiment plots consisted of such three levels as 90% (Dense), 70% (Moderate), and 50% Sparse of the density of the coarse straw-mat mulchings. The main results obtained may be summarized as follows: 1. The rates of surface runoff are calculated as 13.13% from the dense mulchings, 14.21% from the moderate mulchings, and 15.57% from the sparse mulchings respectively. 2. The total amounts of soil loss are measured as about 1.24 tons/ha. from the dense mulchings, about 1.33 tons/ha. from the moderate mulchings, and about 1.44 tons/ha. from the sparse mulchings respectively. The amounts of soil loss under these treatments are much lower than the standard of erosion in USDA (1939 Bennet). 3. Average numbers of germination by treatment are counted as 80 seedlings at the dense mulchings. 132 at the moderates and 121 at the sparse respectively. Large numbers of seedling are suppressed and died during the growing at the dense mulchings due to mainly mechanical obstruction. 4. Coarse straw-mat having about 70% of coverage density is the most suitable mulches in both soil erosion control and vegetation establishment. 5. The method of coarse straw-mat mulching is the most recommendable measure for establishing the vegetation cover with less soil erosion on the denuded gentle slopes in hillsides at present in Korea.

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Electrochemical Characteristics of Transition Metal Pyrophosphate as Negative Electrode Materials through Solid-state Reaction (고상법으로 합성된 리튬이온 이차전지용 음극물질로서 전이금속 피로인산화물의 전기화학적 특성)

  • Hong, Min Young;An, Sang-Jo;Ryu, Ji Heon
    • Journal of the Korean Electrochemical Society
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    • v.23 no.4
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    • pp.105-112
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    • 2020
  • Transition metal oxide, which undergoes a conversion reaction in the negative electrode material for a lithium-ion batteries, has a high specific capacity, but still has several critical problems. In this study, manganese pyrophosphate (Mn2P2O7), nickel pyrophosphate (Ni2P2O7), and carbon composite materials with pyrophosphates as novel negative electrode materials instead of transition metal oxide, are synthesized through simple solid-state reaction. The initial reversible capacity of Mn2P2O7 and Ni2P2O7 are 333 and 340 mAh g-1, and when the composite materials are composed with carbon, the reversible capacity increases to 433 and 387 mAh g-1, respectively. The initial Coulombic efficiency is also improved by about 10%. The Mn2P2O7 and carbon composite material has the highest initial capacity and efficiency, and has the best cycle performance. Mn2P2O7 containing polyanion, has a lower specific capacity due to the large mass of polyanion compared to MnO (manganese oxide). However, since Mn2P2O7 shows a voltage curve with a slope, the charging (lithiation) voltage increases from 0.51 to 0.57 V (vs. Li/Li+), and the discharge (delithiation) voltage decreases from 1.15 to 1.01 V (vs. Li/Li+). Therefore, the voltage efficiency of the cell is improved because the voltage difference between charging and discharging is greatly reduced from 0.64 to 0.44 V, and the operating voltage of the full cell increases because the negative electrode potential is lowered during the discharging process.

Physical Geography of Munkyung (문경의 자연지리)

  • Bak, Byeong-Su;Son, Myoung-Won
    • Journal of the Korean association of regional geographers
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    • v.4 no.2
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    • pp.15-30
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    • 1998
  • Physical geography is the discipline which deals with the relationship between man and natural environment. Therefore, it should be studied as the organized unity. In this paper I recognize the drainage basin as a framework outlining physical geography, describe the difference of inhabitant's life style due to the difference of natural environment in the drainage basin, and consider the meaning of drainage basin as a unit of life(and unit of regional geography). Munkyung is divided into three regions(intermontane basin region, middle mountainous region, marginal hilly region of the great basin) owing to the topographic characteristics. Subdivision in these regions is related closely to drainage network distribution, specially in intermontane basin region. And small regions have developed with the confluence point of $3{\sim}4$ order streams as the central figure. Intermontane basin region is the valley floor of Sinbuk-Soya-Kauun-Nongam stream located in the limestone region which is exposed according to Munkyung fault at its northern part. Small streams are affected strongly by the influence of the NNE-SSE or WNW-ESE tectolineament. Thus Kaeripryungro(鷄立嶺路), Saejaegil(새재길), Ewharyungro(伊火嶺路) and so on are constructed through the tectolineament. In the valley floors of small streams which flow into the intermontane basin, there are large floodplains. Floodplain in Sinbuk, Joryung, and Yangsan stream is used to paddy field or orchard, and in Nongam stream is used to paddy field or vegetable field. Hills are distributed largely in the periphery of intermontane basin. Limestone hills in Kauun and Masung basin are not continuous to the present low and flat floodplain, and most of those are used to forest land and field. On the other side. granite hills in Koyori are continuous to be used to the present floodplain, and they are used to residential area and field. In the middle mountainous region are there hilly mountains constructed in the geology of Palaeozoic Pyeongan System in northern area and Chosun System's Limestone Series in southern area, and banded gneiss and schist among Sobaeksan Gneiss Complex. In Palaeozoic Pyeongan System region are there relatively rugged mountains and ingrown meanders developed along tectolineaments. Chosun System's Limestone Series region builds up a geomorphic surface, develops various karst landforms. Mountainous area is used to field. On the other hand, especially in case of Hogye, valley bottom is wide, long, and discontinuous to slope, is used to paddy field dominantly. And schist region in Youngnam Block of Pre-Cambrian is rugged mountainous. Marginal hilly region of the great basin is hilly zone located in the margin of erosional basin(Bonghwa-Youngju-Yechon-Hamchang-Sangju). This region is lower geomorphic surface which is consisted of hills of $50{\sim}100$m height. Hills are used to field or orchard, and dissected gentle depression is used to paddy field.

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Estimation of Microclimate by Site Types in Natural Deciduous Forest and Relation between Periodic Annual Increment of Diameter and the Microclimatic Estimates - A Case Study on the National Forest in Pyungchung, Kangwon Province - (천연 활엽수림의 입지 유형별 미기후 추정과 직경생장과의 관계 - 강원도 평창 지역 국유림을 중심으로 -)

  • 신만용;정상영;이돈구
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.3 no.1
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    • pp.44-54
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    • 2001
  • This study was conducted to estimate microclimate of natural deciduous forest in national forest of Pyungchang, Kangwon province and to investigate the effects of the microclimatic conditions on the periodic annual increment of diameter by site types. In this study, site was first classified by nine types considering both elevation (higher than 1,000 m, 700∼1,000 m, and lower than 700 m) and topographical conditions (ridge, slope and valley). For each of site types, diameter growth was measured by using increment borer and periodic annual increment of diameter was then analyzed. A topoclimatological technique, for estimating microclimatic conditions, which make use of empirical relationships between the topographical factor and the climatic normals in the study area was applied to produce monthly mean, maximum and minimum temperatures, relative humidity, precipitation and hours of sunshine. From these monthly estimtes, 17 weather variables such as warmth index, coldness index, index of aridity etc. which affect the diameter growth were computed for each of site types. The periodic annual increment of diameter was then correlated with and regressed on the 17 weather variables to examine effects of microclimatic conditions on the diameter growth by site types. From the correlation analysis, it was found that the diameter growth by site types was positively correlated with all of 17 weather variables except the warmth index. Especially, the conditions such as high relative humidity and large amount of sunshine hours provide favorable environment for the growth of diameter. On the other hand, it was also found that diameter growth was negatively iufluenced by warmth index. According to the regression analysis, the periodic annual increment of diameter could be well predicted by index of aridity and mean relative humidity for the growing season.

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Evaluation of Shear Bond Strength and Adhesive Bond Durability of Mixed Species Structural Glued Laminated Timber (이수종 구조용집성재의 전단접착력 및 접착내구성 평가)

  • Shim, Sangro;Yeo, Hwanmyeong;Shim, Kugbo
    • Journal of the Korean Wood Science and Technology
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    • v.33 no.1 s.129
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    • pp.87-96
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    • 2005
  • This study was carried out to evaluate the shear bond strength and adhesive bond durability of structural glued laminated timber (glulam) manufactured with mixed species lumber of Korean red pine, Korean pine and Japanese larch, using resorcinol adhesive and water-based polymeric-isocyanate adhesive (WPI). Each board used as a glulam lamina was graded by visual inspection. The visual lumber grade of the all species was very low due to the large size and number of knots and the steep slope of grain. In view of the results, appropriate pruning, sawing and drying processes might be needed to produce high grade lamina lumber with small knot size and drying defect free. Shear bond strength of every tested glulam specimen ranged between 7.9 and $9.9N/mm^2$, and much higher than the Korean Standard (KS) for glulam shear bond strength, $7.1N/mm^2$. There was not much shear bond strength difference between wood/resorcinol and wood/WPI. The resorcinol adhesive bond durability exceeded KS requirements. However, delamination on the end-grain surfaces of WPI glulam submerged in both room temperature and boiling water severely occurred, and its durability did not meet KS requirements. Further investigations may be required, and special care should be taken, to ensure long service life of WPI glulam used for exterior application. Results of this study are expected to be useful for improvement of mechanical properties and structural performance of mixed species glulam.

A Study on the Damage of Pine Stand by Snowfall (항설(降雪)에 의(依)한 소나무 임분(林分)의 피해(被害)에 관(關)한 연구(硏究))

  • Ma, Ho Seop;Kang, Wee Pyeong;Kim, Jai Saing
    • Journal of Korean Society of Forest Science
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    • v.73 no.1
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    • pp.63-69
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    • 1986
  • In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.

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Groundwater Recharge Evaluation on Yangok-ri Area of Hongseong Using a Distributed Hydrologic Model (VELAS) (분포형 수문모형(VELAS)을 이용한 홍성 양곡리 일대 지하수 함양량 평가)

  • Ha, Kyoochul;Park, Changhui;Kim, Sunghyun;Shin, Esther;Lee, Eunhee
    • Economic and Environmental Geology
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    • v.54 no.2
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    • pp.161-176
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    • 2021
  • In this study, one of the distributed hydrologic models, VELAS, was used to analyze the variation of hydrologic elements based on water balance analysis to evaluate the groundwater recharge in more detail than the annual time scale for the past and future. The study area is located in Yanggok-ri, Seobu-myeon, Hongseong-gun, Chungnam-do, which is very vulnerable to drought. To implement the VELAS model, spatial characteristic data such as digital elevation model (DEM), vegetation, and slope were established, and GIS data were constructed through spatial interpolation on the daily air temperature, precipitation, average wind speed, and relative humidity of the Korea Meteorological Stations. The results of the analysis showed that annual precipitation was 799.1-1750.8 mm, average 1210.7 mm, groundwater recharge of 28.8-492.9 mm, and average 196.9 mm over the past 18 years from 2001 to 2018 in the study area. Annual groundwater recharge rate compared to annual precipitation was from 3.6 to 28.2% with a very large variation and average 14.9%. By the climate change RCP 8.5 scenario, the annual precipitation from 2019 to 2100 was 572.8-1996.5 mm (average 1078.4 mm) and groundwater recharge of 26.7-432.5 mm (average precipitation 16.2%). The annual groundwater recharge rates in the future were projected from 2.8% to 45.1%, 18.2% on average. The components that make up the water balance were well correlated with precipitation, especially in the annual data rather than the daily data. However, the amount of evapotranspiration seems to be more affected by other climatic factors such as temperature. Groundwater recharge in more detailed time scale rather than annual scale is expected to provide basic data that can be used for groundwater development and management if precipitation are severely varied by time, such as droughts or floods.

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.

Characteristics of Environmental Factors and Vegetation Community of Zabelia tyaihyonii (Nakai) Hisauti & H.Hara among the Target Plant Species for Conservation in Baekdudaegan (백두대간 중점보전종인 댕강나무의 식생 군집 및 환경인자 특성)

  • Kim, Ji-Dong;Lee, Hye-Jeong;Lee, Dong-Hyuk;Byeon, Jun Gi;Park, Byeong Joo;Heo, Tae-Im
    • Journal of Korean Society of Forest Science
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    • v.111 no.2
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    • pp.201-223
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    • 2022
  • Currently, species extinctions are increasing due to climate change and continued anthropogenic impact. We selected 300 species for conservation with emphasis on plants co-occurring in the Baekdudaegan area, which is a large ecological axis of Korea. We aimed to investigate the vegetation community and environmental characteristics of Zabelia tyaihyonii in the limestone habitat among the target plant species in the Baekdudaegan region to derive effective conservation strategies. In Danyang-gun, Yeongwol-gun, and Jecheon-si, we selected 36 investigation sites where Z. tyaihyonii was present. We investigated the vegetation, flora, soil and physical environment. We also found notable plants such as Thalictrum petaloideum, Sillaphyton podagraria, and Neillia uekii at the investigation sites. We classified forest vegetation community types into 4 vegetation units and 7 species group types. With canonical correspondence analysis (CCA) of the vegetation community and habitat factors, we determined the overall explanatory power to be 75.2%, and we classified the environmental characteristics of the habitat of Z. tyaihyonii into a grouping of three. Among these, we detected a relationship between the environmental factors elevation, slope, organic matter, rock ratio, pH, potassium, and sodium. We identified numerous rare and endemic plants, including Thalictrum petaloideum, in the investigation site, and determined that these groups needed to be preserved at the habitat level. In the classification of the vegetation units analyzed based on the emerging plants and the CCA, we reaffirmed the uniqueness and specificity of the vegetation community in the habitat of Z. tyaihyonii. We anticipate that our results will be used as scientific evidence for the empirical conservation of the native habitats of Z. tyaihyonii.