• 제목/요약/키워드: alpine

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고령지 농경지에서 융설에 의한 토양유실량 모의 (Simulation of Soil Erosion due to Snow Melt at Alpine Agricultural Lands)

  • 허성구;임경재;김기성;사공명;안재훈
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2005년도 학술발표논문집
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    • pp.241-246
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    • 2005
  • Doam watershed is located at alpine areas in the Kangwon province. The annual average precipitation, including snow accumulation during the winter, at the Doam watershed is significantly higher than other areas. Thus, pollutant laden runoff and sediment discharge from the alpine agricultural fields are causing water quality degradation at the Doam watershed. To estimate soil erosion from the agricultural fields, the Universal Soil Loss Equation (USLE) has been widely used because of its simplicity to use. The USLE rainfall erosivity (R) factor is responsible for impacts of rainfall on soil erosion. Thus, use of constant R factor for the Doam watershed cannot reflect variations in precipitation patterns, consequently soil erosion estimation. In the early spring at the Doam watershed, the stream flow increases because of snow melt, which results in erosion of loosened soil experiencing freezing and thaw during the winter. However, the USLE model cannot consider the impacts on soil erosion of freezing and thaw of the soil. Also, it cannot simulate temporal changes in USLE input parameters. Thus, the Soil and Water Assessment Tool (SWAT) model was investigated for its applicability to estimate soil erosion at the Doam watershed, instead of the widely used USLE model. The SWAT hydrology and erosion/sediment components were validated after calibration of the hydrologic component. The $R^2$ and Nash-Sutcliffe coefficient values are higher enough, thus it was found the SWAT model can be efficiently used to simulate hydrology and sediment yield at the Doam watershed. The effects of snow melt on SWAT estimated stream flow and sediment were investigated using long-term precipitation and temperature data at the Doam watershed. It was found significant amount of flow and sediment in the spring are contributed by melting snow accumulated during the winter. Thus, it is recommend that the SWAT model capable of simulating snow melt and long-term weather data needs to be used in estimating soil erosion at alpine agricultural land instead of the USLE model for successful soil erosion management at the Doam watershed.

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Comparison of Three-dimensional Kinematic Changes of the Lower Extremity between the Two Different Braking Distances of Snowplow in Alpine Skiing

  • Kim, Joo-Nyeon;Kim, Jin-Hae;Ryu, Jiseon;Yoon, Sukhoon;Park, Sang-Kyoon
    • 한국운동역학회지
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    • 제26권4호
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    • pp.361-367
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    • 2016
  • Objective: The aim of this study was to compare three-dimensional kinematic changes of the lower extremity between the two different braking distances during snowplow in alpine skiing. Method: Six alpine ski instructors (age: $25.3{\pm}1.5yr$, height: $169.3{\pm}2.9cm$, weight: $66.2{\pm}5.9kg$, career: $4.2{\pm}2.9yr$) participated in this study. Each skier was asked to perform snowplow on the two different braking distances (2 and 4 m). Results: Snowplow and edging angles (p = .006 and p = .005), ankle adduction and inversion (p = .033 and p = .002), knee extension (p = .003), and hip abduction and internal rotation (p = .043 and p = .006) were significantly greater in the 2 m than in the 4 m braking distance. Conclusion: Based on our results, we suggest that skiers should make greater snowplow and edging angles on the shorter braking distance. In this situation, ankle joint adduction/inversion angle and hip joint internal-rotation make greater snowplow angle, and hip joint abduction make greater edging angle. In addition, greater knee joint extension angle may lead to more posteriorly positioned center of mass.

설악산, 지리산, 한라산 산정부의 식생과 경관 특성 (Vegetation and Landscape Characteristics at the Peaks of Mts. Seorak, Jiri and Halla)

  • 공우석;김건옥;이슬기;박희나;김현희;김다빈
    • 한국기후변화학회지
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    • 제8권4호
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    • pp.401-414
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    • 2017
  • Vegetation and landscape characteristics at the three highest summits of Republic of Korea, i.e. Seoraksan, Jirisan and Hallasan, are analyzed on the basis of species composition, physiognomy, vegetation distribution and structure of alpine plants, along with landform, geology, soil and habitat conditions. Dominant high mountain plants at three alpine and subalpine belts contain deciduous broadleaved shrub, Rhododendron mucronulatum var. ciliatum (31.6%), and evergreen coniferous small tree, Pinus pumila (26.3%) at Seoraksan, deciduous broadleaved tree, Betula ermanii (35.3%), evergreen coniferous tree, Picea jezoensis (23.5%) at Jirisan, and evergreen coniferous tree, Abies koreana (22.6%), deciduous broadleaved shrub, Rhododendron mucronulatum var. ciliatum, and Juniperus chinensis var. sargentii (19.4%) at Hallasan, respectively. Presence of diverse landscapes at the peak of Seoraksan, such as shrubland, grassland, dry land along with rocky areas, and open land may be the result of hostile local climate and geology. High proportion of grassland and wetland at the top of Jirisan may related to gneiss-based gentle topography and well developed soil deposits, which are beneficial to keep the moisture content high. Occurrence of grassland, shrubland, dry land, conifer vegetation, and rocky area at the summit of Hallasan may due to higher elevation, unique local climate, as well as volcanic origin geology and soil substrates. Presences of diverse boreal plant species with various physiognomy at alpine and subalpine belts, and wide range of landscapes, including rocky, grassland, shrubland, wetland, and conifer woodland, provide decisive clues to understand the natural history of Korea, and can be employed as an relevant environmental indicator of biodiversity and ecosystem stability.

사자평 고산습지의 보전대책 (Conservation Measure of Sajapyeong Alpine Wetland)

  • 손명원
    • 한국지역지리학회지
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    • 제17권2호
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    • pp.141-149
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    • 2011
  • 사자평 고산습지는 유역분지 및 기반암의 특성과 화전의 영향을 받아 형성되었다. 사자평 유역분지는 출구가 좁고, 기반양은 많은 암설을 생산하여 사면 아래로 공급한다. 그리고 화전을 위하여 삼림을 제거함으로써 표토의 세립물질이 사전천의 하상에 퇴적되어, 시전천의 유로 주변에 고산습지가 형성되었다 사자평의 습원에는 도로를 따라 우곡이 형성되었는데, 우곡은 습원으로 공급되는 사력물질과 통류의 공급을 차단함으로써 습원을 건조화 시킨다. 이를 방지하기 위해서는 배수로의 수위를 기반암 풍화층의 높이까지 높여 습원으로 통류가흐를 수 있도록 하여야 하며, 배수로의 모양을 자연스러운 불규칙한 형태로 조정하여야 하고 시전천의 하상에 인위적인 방해물을 적치하여 시전천의 하상이 낮아지는 것을 방지하여야 한다.

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Dynamics of alpine treelines: positive feedbacks and global, regional and local controls

  • Kim, Jong-Wook;Lee, Jeom-Sook
    • Journal of Ecology and Environment
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    • 제38권1호
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    • pp.1-14
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    • 2015
  • Whilst it is clear that increasing temperatures from global environmental change will impact the positions of alpine treelines, it is likely that a range of regional and local scaled factors will mediate the overall impact of global scale climate drivers. We summarized 12 categories of abiotic and biotic factors as 4 groups determining treeline positions. First, there are global factors related to climate-induced growth limitation and carbon limitation. Second, there are seven regional and local factors related to treeline dynamics including frost stress, topography, water stress, snow, wind, fire and non-fire disturbance. Third, species-specific factors can control treeline dynamics through their influence on reproduction and life history traits. Fourth, there are positive feedbacks in structuring the dynamics of treelines. Globally, the commonly accepted growth limitation hypothesis is that growth at a treeline is limited by temperature. Meanwhile, positive feedbacks between canopy cover and tree establishment are likely to control the spatial pattern and temporal dynamics of many treelines. The presence of non-linear dynamics at treelines has implications for the use of treelines as barometers of climate change because the lagged responses and abrupt shifts inherent in non-equilibrium systems may combine to mask the overall climate trend.

고지 사육 도태유우의 번식실태와 생식기 부검에 관한 연구 (Studies on the Reproductive Performence and Organs Autopsy of Culled Dairy Cow at Alpine Area)

  • 이상영;김정익
    • 한국가축번식학회지
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    • 제17권4호
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    • pp.295-303
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    • 1994
  • The present study was conducted to examine the reprodutive performance and organs autopsy of culled dairy cows at alpine area. 795 culled dairy cows were managed and 206 culled dairy cows were examined by autopsy of reproductive organs at above 800m of sea level around the Daegwallryoung alpine area. The results of this study were at follows ; 1. Age and parity of culled dairy cows were 60.8 months and 3.0, respectively. 2. Age of first AI of heifer was 18.7 months, and age of pregnancy and parturition of heifer were 19.5 months and 28.6 months, respectively. 3. Al time per pregnancy was 1.7 and time of pregnancy after parturition, pregnancy period and calving interval were 140.9, 279.6 and 424.9 days, respectively. 4. Culled months after last parturition was 4.3 and the highest urogenital deseases of culled reason were 358(45.0%). 5. Reproductive organs deseases by autopsy were 120(58.4%), the highest ovary disease were 75(43.6%). 6. The highest ovary adhesions of reproductive organ diseases were 46(26.7%), infundibulum adhesion, obstruction of the oviduct and endometritis were 38(22.1%), 15(8.7%), and 14(8.2%), respectively. 7. In culled dairy cow for the reproductive organ disease, parity, age, culled months and AI number after last parturition were 3.2, 66.5 months, 7.9 months and 2.1, respectively.

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