• 제목/요약/키워드: vegetation covering

검색결과 68건 처리시간 0.022초

개수로 내 식생구간의 흐름저항 및 흐름특성에 관한 실험적 고찰 (Experimental Study of Flow Resistance and Flow Characteristics over Flexible Vegetated Open Channel)

  • 여홍구;박문형;강준구;김태욱
    • 한국환경복원기술학회지
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    • 제7권6호
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    • pp.61-74
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    • 2004
  • Hydraulic engineers and scientists working on river restoration recognize the need for a deeper understanding of natural streams as a complex and dynamic system, which involves not only abiotic elements(flow, sediments) but also biotic components. From this point of view, the role played by riverine vegetation dynamics and flow conditions becomes essential. Hydro-mechanic interaction between flow and flexible plants covering a river bed is studied in this paper and some previous works are discussed. Measurements of turbulence and flow resistance in vegetated open channel were performed using rigid and flexible tube. Measuring detailed turbulent velocity profiles within and above submerged and flexible stems allowed to distinguish different turbulent regimes. Some interesting relationships were obtained between the velocity field and the deflected height of the plants, such as a reduced drag coefficient in the flexible stems. Turbulent intensities and Reynolds stresses were measured showing two different regions : above and inside the vegetation domain. In flexible vegetated open channel, the maximum values of turbulent intensities and Reynolds stresses appear above the top of canopy. Method to predict a flow resistance in flexible vegetated open channel is developed by modifying an analytical model proposed by Klopstra et al. (1997). Calculated velocity profiles and roughness values correspond well with flume experiments. These confirm the applicability of the presented model for open channel with flexible vegetation. The new method will be verified in the real vegetated conditions in the near future. After these verifications, the new method should be applied for nature rehabilitation projects such as river restorations.

청송군 옹점리 일대 암설 사면의 분포와 지형 변화 (The Distribution and Geomorphic Change of Debris Slope at Ongjeom-ri in Cheongsong-gun)

  • 이광률;박한산
    • 대한지리학회지
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    • 제45권3호
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    • pp.360-374
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    • 2010
  • 본 연구는 옹점리 동부의 암설 사면을 대상으로 암설 사면의 분포, 요인, 식생 피복 및 암설 변화에 대해 분석하였다. 이 지역에서 암설 사면 발달의 중요한 요인은 기반암이 단애 형성과 암설 공급에 유리한 규장암이라는 점과 기계적 풍화작용을 촉진시키는 기온의 영하일수가 비교적 길다는 점이다. 암설 사면의 분포 면적은 일사량이 높아서 수분 증발이 활발하여 식생 피복이 불량한, 남사면과 서사면이 북사면과 동사면에 비해 더 넓은 것으로 나타났다. 옹점리 동부의 가 지역에서 식생 피복으로 인해 암설 사면의 면적은 꾸준히 감소하고 있으며, 평균 $431.0m^2/yr$의 식생 피복 면적 증가 속도를 보였다. 그리고 지상라이다를 이용하여 분석한 결과, 나 지역에서는 1년 동안 1~2개의 암설 입자들이 사면 내에서 변위 또는 이동되었다.

훼손지 유형에 따른 생태복원 평가방법 개발 (Evaluation Method Development for Ecological Restorations by Damaged Types)

  • 최재용;이상혁;이솔애;지승용;이상훈
    • 한국환경복원기술학회지
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    • 제19권1호
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    • pp.121-133
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    • 2016
  • It was required to evaluate ecological restorations in a comprehensive way in order to systematically manage conservation areas such as DMZ and national parks in South Korea. In this research we developed a new approach to evaluating ecological restorations with more various indexes than vegetation covering-related indexes. By analyzing damaged areas in the vicinity of DMZ, major damaged types were identified as six classes: landform modification, surface loss, soil pollution, soil physio-chemical modification, vegetation decline and vegetation damaged. From literature review, 39 indexes were selected and were grouped into four divisions: soil property, vegetation growth & structure, habitat property and landscape structure & functions. By conducting a survey with the selected indexes targeting relevant experts, data on relative importance among the divisions and indexes by damaged type were collected. As a result, it was found that the orders and values of weighted values of the divisions were different by damaged type: for example, soil property (0.402), vegetation growth & structure (0.209), habitat property (0.225), landscape structure & function (0.163) for "landform modification"; but soil property (0.171), vegetation growth & structure (0.401), habitat property (0.270), landscape structure & function (0.158) for "vegetation decline". Similarly, evaluation indexes showed different orders and values of relative importance, easiness in field measurement and representativeness for the division by damaged type, and the values were used for calculating importance factor for each index. In the evaluation table, score1 and score2 were made by the importance factors of indexes multiplied by distribution values which present grades and by the weighted values of divisions. In conclusion, while dealing with the damaged type was considered significant for evaluating and managing restorations, further tests on this table with a range of cases were needed to improve its quality.

새만금 간척지 토양특성과 친환경 활용 방안 (Construction of Environmental-friendly Infrastructure in Saemangeum Reclaimed Land)

  • 서동욱;전건영;김현태;송재도
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.40-48
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    • 2010
  • Saemangeum reclaimed area is needed to construct much green zone to make high-quality multi-functional land such as tide embankment, lake dike, industrial complex, environmental spaces, etc. However, growth of plants is somewhat difficult because a salinity of Saemangeum soil is very high and a soil fertility, water content of soil are low. Therefore, it is essential to initial desalination of soil and continuous management for planting base. It is recommended that a group of grassland to raise the efficiency of covering should be made in the first stage and a forest by improvement of vegetation should be made in the mid and long term stage. It is recommended that the construction of vegetation base should be made with a regular thickness of soil of good quality in multi-functional area such as a shrub and wood. In case of construction of a windbreak forest, it is necessary to make a wood base of suitable depth using soil brought from another place or filling of soil. Also, it is necessary to keep a maintenance of woods in early stage. Saemangeum reclaimed land will be brand-named worldwide tourist attractions due to construction of much green zone having high quality multi-functional facilities.

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국립공원 Sequence 경관의 기호학과 계량심리학적 분석에 관한 연구 (A Study on the Semiology and Quantitative Psychological Analysis of Sequence Landscape of National Park)

  • 김세천
    • 한국조경학회지
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    • 제19권3호
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    • pp.55-71
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    • 1991
  • The purpose of this thesis is to suggest objective basic data for the environmental design through the quantitative analysis of the visual quality included in the physical environment of Basemsagol valley sequence landscape. For this, visual volumes of physical elements have been evaluated by using the mesh analysis, spatial images structure of physical elements have been analyzed by factor analysis algorithm, and degree of visual quality have been measured mainly by questionnaires. Also, this study aims to understand semiotics and to grope the possibility of application to the sequence landscape assessment. A semiological approach suggests a new dimension in sequence landscape assessment, which is a contrast to the existing scientific evaluation methods. Result of this thesis can be summarized as follows. Visual volumes of the immediate vegetation, rock, bridge, road and distant vegetation are found to be the main factor determining the visual quality. Factors covering the spatial image of natural park sequence landscape have been found to be the overall synthetic evaluation, potentiality, natural quality, spatial, appeal and dignity. By using the control method for the number of factors, T.V. has been obtained as 40.22%. The characteristics of the semiological approach is qualitative, open, holistic, and experiential, whereas that of the scientific approach is quantitative, closed, reductive, and experimental.

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무인비행체 영상을 활용한 벼 수량 분포 추정 (Estimation of Rice Grain Yield Distribution Using UAV Imagery)

  • 이경도;안호용;박찬원;소규호;나상일;장수용
    • 한국농공학회논문집
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    • 제61권4호
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    • pp.1-10
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    • 2019
  • Unmanned aerial vehicle(UAV) can acquire images with lower cost than conventional manned aircraft and commercial satellites. It has the advantage of acquiring high-resolution aerial images covering in the field area more than 50 ha. The purposes of this study is to develop the rice grain yield distribution using UAV. In order to develop a technology for estimating the rice yield using UAV images, time series UAV aerial images were taken at the paddy fields and the data were compared with the rice yield of the harvesting area for two rice varieties(Singdongjin, Dongjinchal). Correlations between the vegetation indices and rice yield were ranged from 0.8 to 0.95 in booting period. Accordingly, rice yield was estimated using UAV-derived vegetation indices($R^2=0.70$ in Sindongjin, $R^2=0.92$ in Donjinchal). It means that the rice yield estimation using UAV imagery can provide less cost and higher accuracy than other methods using combine with yield monitoring system and satellite imagery. In the future, it will be necessary to study a variety of information convergence and integration systems such as image, weather, and soil for efficient use of these information, along with research on preparing management practice work standards such as pest control and nutrient use based on UAV image information.

도로비탈면 돌망태공법의 특성 및 경관선호도 분석 (Analysis Gabion Works in Cut-slopes Characteristics and Scenic Preference)

  • 박재현;김춘식
    • 한국산림과학회지
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    • 제104권2호
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    • pp.206-212
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    • 2015
  • 이 연구는 우리나라의 도로비탈면에 주고 적용하고 있는 돌망태공법의 특성을 조사, 분석하고 경관선호도를 분석하였다. 임도 및 도로비탈면에 시공한 97개소의 돌망태를 대상으로 조사한 결과, 10가지 유형으로 분석되었다. 비탈면 경사도에 따른 돌망태 시공지를 분석한 결과, 비탈면 경사 10% 이하지역에서는 돌망태가 30개소(31%), 11~30%의 경사에서는 31개소(32%), 31~50%의 경사에서는 20개소(21%), 51~80%에서는 16개소(16%)로 비탈면의 경사가 낮을수록 돌망태를 많이 시공하는 것으로 분석되었다. 총조사지 중 돌망태에 식생이 피복되지 않은 개소수는 34개소(35%)로 나타났으며, 1~30% 정도의 식생피복을 나타낸 개소수는 52개소(54%)로 가장 높게 나타났다. 설문조사를 통한 경관분석 결과 일반인집단은 비탈면에 돌망태를 시공할 때 식생으로 피복되는 것이 경관을 좋게 하는 요인으로 의식하고 있었다. 전문가집단은 비탈면에 돌망태만 처리한 경관을 가장 선호하였으며, 그 다음으로는 비탈면에 돌망태를 시공할 때 식생으로 피복되는 것이 경관을 좋게 하는 요인으로 판단하고 있는 것으로 분석되었다.

호안자연직생 복원을 위한 갈대류(Phragmites spp.) 뗏장개발 - 토양의 조성 및 반종량이 달뿌리(Phragmites japonica)뗏장 형성에 미치는 영향 (A Study on Development of Phragmites spp. Sod for Restoration of Shore Vegetation -Effects of Soil Compositions and Seeding rates on the Development of Phragmites japonica Sod-)

  • 정대영;심상렬
    • 한국조경학회지
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    • 제26권1호
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    • pp.28-35
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    • 1998
  • Six soil compositions with three seeding rates were evaluated for influence on germination, coverage, height and sod development of Phragmites japonica. 1. Germination was high on peat, vermiculite and bark as compared with on peatmoss and sandy loam. 2. Covering rate was high within 2 months when seeded at 9g/$m^2$, but became same within 3 months afterwards when seeded at 3,6 and 9g/$m^2$, respectively. 3. Sod was highly developed on peat and bark treatments whereas Sandy loam, peatmoss and vermiculite treatments didn't develop sod. 4. Sod grown on bark weighed light and, therefore, was suggested best from a dealing cost point of view. 5. Cutting at 10 cm height didn't influence on sod development regardless of soil compositions.

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The retrieval of Surface Solar Insolation using SMAC code with GMS-5 satellite data

  • Yeom, Jong-Min;Han, Kyung-Soo;Kim, Young-Seup
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.458-461
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    • 2005
  • Surface Solar Insolation is important for vegetation productivity, hydrology, crop growth, etc. However, ground base measurement stations installed pyranometer are often sparsely distributed, especially over oceans. In this study, Surface Solar Insolation is estimated using the visible and infrared spin scan radiometer(VISSR) data on board Geostationary Meteorological Satellite (GMS)-S covering from March 2001 to December 2001 in clear and cloudy conditions. To retrieve atmospheric factor, such as, optical depth, the amount of ozone, H20, and aerosol, SMAC (Simplified Method for Atmospheric Correction) code, is adopted. The hourly Surface Solar Insolation is estimated with a spatial resolution of $5km\;\times\;5km$ grid. The daily Surface Solar Insolation is derived from the available hourly Surface solar irradiance, independently for every pixel. The pyranometer by the Korea Meteorological Agency (KMA) is used to validate the estimated Surface Solar Insolation with a spatial resolution of $3\;\times\;3Pixels.$

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Mechanical Properties of Carbon Fiber Reinforced Porous Concrete for Planting

  • Park Seung-Bum;Kim Jeong-Hwan
    • KCI Concrete Journal
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    • 제14권4호
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    • pp.161-169
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    • 2002
  • The mechanical properties of fiber reinforced porous concrete for use as a planting material were investigated in this study. Changes in physical and mechanical properties, subsequent to the addition of carbon fiber and silica fume, were studied. The effects of recycled aggregate were also evaluated. The applicability as planting work concrete material was also assessed. The results showed that there were no remarkable changes in the void and strength characteristics following the increase in proportion of recycled aggregate. Also, the mixture with 10% silica fume was found to be the most effective for strength enforcement. The highest flexural strength was obtained when the carbon fiber was added with $3\%$. It was also noticed that PAN-derived carbon fiber was superior to Pitch-derived ones in view of strength. The evaluation of its usage for vegetation showed that the growth of plants was directly affected by the existence of covering soil, in case of having the similar size of aggregate and void.

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