• 제목/요약/키워드: valley water

검색결과 249건 처리시간 0.025초

Analysis for the relationship of environmental factors and vegetation structure at natural streamside valley and riparian forest in South Korea

  • Cho, Kyu-Tae;Jang, Rae-Ha;You, Young-Han
    • Journal of Ecology and Environment
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    • 제38권4호
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    • pp.405-413
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    • 2015
  • We classified the streamside plant community by phyto-sociological method and analyzed the relationship between environment factors and vegetation structure by using the classification and ordination method. We found that twenty one plant communities were classified according to dominant species at the natural streamside valley forest with surveying the 65 quadrats (10 m × 10 m). From the survey results, the hardwood plant communities were classified as streamside valley forest and the softwood plant communities as riparian forest according to the degree of flooding. The valley forest had a distribution of 17 plant communities which was 65% (42 quadrats) of 65 quadrats: Maackia amurensis community, Betula davurica community, Quercus variabilis community, Pinus densiflora community, Q. serrata community, Prunus sargentii community, and Meliosma oldhamii community etc. The riparian forest had a distribution of four plant communities which was 35% (23 quadrats) of 65 quadrats: Salix koreensis community, S. rorida community, S. purpurea var. japonica community, and S. glandulosa community, etc. From the two-way indicator species analysis (TWINSPAN) analysis, we found indicator species Oplismenus undulatifolius and Lindera obtusiloba for the streamside valley forest and Humulus japonicus, Phragmites japonica, and S. koreensis for the riparian forest. From the results of the canonical correspondence analysis (CCA), coordinates, altitude, and stream structure showed low correlation to the distribution of the plant community. Therefore, it seemed that valley forest and riparian forest were distinguished by the stream gradient and waterway width which determined by the stream water level.

자연계에 있어 부유사 발생원의 특성에 관한 연구 (A research on the features of suspended sediments origination in natural world)

  • 이성기
    • 한국환경과학회지
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    • 제11권6호
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    • pp.483-488
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    • 2002
  • Suspended sediment outflows mainly by natural situation and artificial action and affects in down-stream. This research studied suspended sediments origination in forests size and mountain stream for natural situation, density for artificial action, and measured the size and possible quantity of suspended sediments origination and studied obstruction method of the generation by artificial action. As the result, I found that the size of generation is about 2~3% of forest size and the forest size which is affecting bare area of valley is about 1∼2ha. In addition, possible outflow segments quantity by artificial facilities is assumed to be maximum 200ton/ha and abstract of mountain incline for mountain development needs minimize bare area valley by make right angle with minimum size.

일산충적평야의 홀로세 퇴적환경변화와 해면변동 (The Holocene Depositonal Environment and Sea-Level Change at Ilsan Area)

  • 황상일
    • 대한지리학회지
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    • 제33권2호
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    • pp.143-163
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    • 1998
  • In order to clarify the depositional environment and sea-level change at Ilsan area including Gawaji and Saemal valley plains, which is located at the right side in downstream of the Han River, boring data, radiocabon dating and diatom analysis were comprehensively investigated. As a result, the palaeogeographies fo this area altered by the transgressions and regressions after 7,000 y. BP could be restored. The high tide sea-level(mean high water level of spring tide) was arrived ca. 7,000y. BP at the valley plain and risen to ca. 5.5m at ca. 5000y. BP. Since then, the sea-level was kept up the same level to ca. 3,200 BP. The descended sea-level to ca. 2,300 BP was risen up to ca. 5.8m in ca. 1,800 y. BP. It is presumed that such a sea-level change as well as the different sediments in quantity supplied from the river basin of the valley plain could be effected to change diversely the depositional environment of the study area and eventually to the prehistoric human life.

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설악산국립공원 천불동 계곡에서 발생된 낙석 거동분석 (Analysis for Behavior of Rockfall Movement by Cheonbuldong Valley of Seoraksan National Park)

  • 조용성;김유성
    • 한국지반공학회논문집
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    • 제26권5호
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    • pp.49-55
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    • 2010
  • 2007년 2월 22일 설악산국립공원 천불동계곡 병풍교 부근에서 대규모 낙석이 발생하였고, 탐방로가 한동안 폐쇄되었었다. 설악산국립공원내에서는 기후변화로 인한 암반의 절리, 풍화와 지표수 등의 급격한 변화로 유사한 낙석사고 빈도가 잦아지고 있다. 이 연구에서는 계곡바닥에서 높이 80m 부근에서 발생한 대규모 낙석의 정밀조사에 근거하여 낙석의 거동을 분석하였고, 낙석에너지를 산정하였다. 분석결과로부터 설악산국립공원내의 자연환경을 훼손하지 않고, 위험요소를 최소화할 수 있는 효과적인 낙석관리방법을 제안하였다.

스마트팜 혁신밸리 입주 청년농업인의 경영성과 분석 (Analysis of Management Performance of Young Farmers in Smart Farm Innovation Valley)

  • 심근호;황금영;이소영;엄지범
    • 현장농수산연구지
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    • 제25권4호
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    • pp.67-77
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    • 2024
  • This study analyzed the profitability and diagnosed business performance of fruit and vegetable (cherry tomatoes, tomatoes, strawberries, cucumbers) businesses targeting young farmers participating in the youth business incubation center of A Smart Farm Innovation Valley. The purpose of this is to provide basic data for decision-making by prospective young entrepreneurs. As a result of the analysis, Smart Farm Innovation Valley had the advantage of having a fixed rental fee. As a result, it was analyzed that various costs such as depreciation of large farm equipment, depreciation of farming facilities, repair and maintenance costs, land rent, floating capital service cost, fixed capital service cost, and land capital service cost are being reduced. However, excessive input of labor, water, electricity, other materials, and fertilizer costs was being made. Guidance to reduce these costs is expected to make a significant contribution to expanding the influx of young farmers.

강원지역 계곡의 물리적 특성 및 고요함 분석 (Analysis of the Physical Characteristics and Tranquility of the Valley in Gangwon Province)

  • 김경남;한갑수
    • Journal of Forest and Environmental Science
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    • 제30권1호
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    • pp.152-160
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    • 2014
  • The purpose of this study is to investigate and analyze the physical characteristics and tranquility of the valleys located in Gangwon region. For this study we analyzed the field survey data 135 valleys using GIS. The elements for measurement of tranquility were divided into visual elements including terrain, objects, forest, water and auditory elements including noise. These elements were divided further into positive and negative factors. The weight of each element and item was calculated by applying the AHP method. The results of this study are as follows. The length of the valley ranged from 126 m to 17 km, and the elevation ranged from 40 m to 1,800 m. Type of mixed forest was common in the valleys. The depth of the water was over 20 cm in 83% of the total area and most of the water was in good condition in visual quality. Regarding the positive factors of tranquility, the weighted scores of the objects, waterfall sounds and visual transparence of the water were of relatively high value. Relatively high values were also shown in closed and curved topography in the landform, forest type and natural forests. In the negative factors, the weights of the objects and forest elements had high values. Within the facility groups, facility of the river produced a considerable negative. After applying the index of tranquility, the natural physical attributes affected the tranquility value, more than the manmade structures to a much greater degree.

관개기 곡간지 유역 필지논에서의 비점원오염물질 유출특성 (Characteristics of Non-Point Sources Pollutant Loads at Paddy Plot Located at the Valley Watershed during Irrigation Periods)

  • 한국헌
    • 한국관개배수논문집
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    • 제18권1호
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    • pp.94-102
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    • 2011
  • The aim of this study was to evaluate the load of non-point sources pollutant at a paddy plot located at the valley watershed during irrigation period. Irrigation, runoff and water quality data in the paddy plot were analyzed periodically from June 1 to October 31 in 2005. The observed amount of precipitation, irrigation, runoff for the experimental paddy plot during the irrigation period was 1,297.8, 223.2, and 825.4mm, respectively. Total-N concentrations ranged from 3.73 to 18.10mg/L, which was generally higher than the quality standard of agricultural water (1.0mg/L). Total-P concentrations ranged from 0.111 to 0.243mg/L and the average was 0.139mg/L. The observed runoff pollutants loadings from the paddy plot were measured as 34.4 kg/ha for T-N, 1.0 kg/ha for T-P and 213.8 kg/ha for SS. The non-point sources pollutant load in drainage water depends on rainfall and surface drainage water amount from the paddy plot. We are considering that these results were affected by rainfall as well as hydrological condition, soil management, whether or not fertilizer application, cropping, rice straw and plowing.

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Influence of Silica Content in Crosslinked PVA/PSSA_MA/Silica Hybrid Membrane for Direct Methanol Fuel Cell (DMFC)

  • Kim, Dae-Sik;Guiver, Michael D.;Seo, Mu-Young;Cho, Hyun-Il;Kim, Dae-Hoon;Rhim, Ji-Won;Moon, Go-Young;Nam, Sang-Yong
    • Macromolecular Research
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    • 제15권5호
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    • pp.412-417
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    • 2007
  • In the present study, crosslinked poly(vinyl alcohol) (PVA) membranes were prepared at different temperatures using poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA) (PVA:PSSA_MA = 1:9). The hybrid mem-branes were prepared by varying the TEOS content between 5 and 30 wt%. The PSSA_MA was used both as a crosslinking agent and the hydrophilic group donor ($-SO_3H$ and/or-COOH). The proton conductivity increased with up to 20 wt% TEOS, but decreased above this level, although the water content decreased with increasing TEOS content. This result suggests that the silica doped into the membrane improved the formation of proton-conduction pathways due to the absorption of molecular water. The PVA/PSSA_MA/Silica containing TEOS 20% showed both high proton conductivity (0.026 S/cm at $90^{\circ}C$) and low methanol permeability ($5.55{\times}10^{-7}cm^2/s$).

한국 하천 모래톱의 지형학적 의미와 효능 - 낙동강 하곡을 사례로 - (Geomorphological significance and role of the sand bars of major river valleys in the South Korea - case study on the Nakdong river valleys -)

  • 오경섭;양재혁;조헌
    • 한국지형학회지
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    • 제18권2호
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    • pp.1-14
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    • 2011
  • 모래톱이 잘 발달함은 한국하천지형의 주요 특징이다. 이는 한편으로는 한국의 기후지형 환경과 관련하여 전국에 널리 분포하는 화강암 풍화 및 풍화층에서 다량의 모래를 하곡으로 공급하기 때문이다. 다른 한편으로는 심하게 굽이치는 곳이 많고 곡폭의 변화가 커서 모래 이동의 병목구간이 많을 수 밖에 없는 하곡의 배열과 형상 때문이다. 그리고 하계 집중호우로 인해 하천의 유황 변동 폭이 크다는 점도 사력퇴를 잘 발달시키는 수리적 요인으로 작용하고 있다. 이 모래톱들은 수분수지 불균형을 조절해주는 역할을 하면서 우수한 수질정화필터 역할을 한다. 이와 함께 모래톱들은 하천 어패류의 서식 산란 공간이 되고, 내륙에 수서성, 반수서성 식생이 군락을 이룰 수 있는 터전 역할을 한다. 모래톱은 자연생태계는 물론 인간 생활에 매우 긍정적 역할을 하고 있다.

의성 빙계계곡 일대의 지형적 특성 -테일러스를 중심으로- (Geomorphic Features of Bing-gye Valley Area(Kyongbuk Province, South Korea) -Mainly about Talus-)

  • 전영권
    • 한국지역지리학회지
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    • 제4권2호
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    • pp.49-64
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    • 1998
  • 연구지역에서 발달하는 테일러스들은 테일러스의 일반적인 특성을 잘 반영하고 있다. 우리나라에 분포하는 테일러스가 보통 rock fall talus이듯이 본 연구지역의 테일러스도 동일한 유형으로 판단된다. 또 테일러스의 사면형태, 형성시기 발달과정, 미지형적 특성 등은 지금까지 발표된 여러 연구결과들과 거의 일치하고 있다. 그러나 인접한 테일러스간의 경계 부분에서는 암설입경의 상대적 크기에 따라 약간의 지형적 차이점을 인식할 수 있었다. 특히 본 연구에서는 테일러스 암설 최적층의 내부구조를 국내 처음으로 확인하여 3가지의 뚜렷한 층위를 구분할 수 있었다. 즉, 암설로만 구성된 표층과 암실과 세립물질(실트질 모래)이 혼재된 중간층 그리고 과거의 토양층인 기저층 등으로 구분된다. 또 암설 퇴적층에 대한 내부구조 인식은 테일러스 형성 당시로 부터 현재까지의 기후환경과 암설의 퇴적양상을 밝히는데 매우 중요하며 앞으로 이 분야의 연구에 큰 도움을 줄 것으로 생각된다. 한편 국지적으로 특수기상이 나타나는 빙혈이 있는 빙계계곡의 경우 그것의 형성에는 단층작용의 역할이 중요한 것으로 판단된다. 그러나 이 곳을 흐르는 쌍계천이 유독 빙계계곡에서만 협곡(빙계계곡의 폭은 주변 곡쪽의 $1/8{\sim}1/10$정도임)을 형성하는 이유에 대해서 정곡의 가능성을 제시했지만 입증할 만한 자료가 없는 것이 유감이다.

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