• Title/Summary/Keyword: 자연하천

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Preliminary Studies on the Necropsy-Based Health Assessment Index (HAI) Using a Ecological Indicator Species (생태 지표종을 이용한 해부학적 건강성 평가지수(HAI) 적용을 위한 예비실험)

  • Kim, Ja-Hyun;Bae, Dae-Yeul;Lee, Jae-Yon;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.39 no.1 s.115
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    • pp.62-72
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    • 2006
  • Biological health in aquatic environments has been assessed by several approaches using various bio-taxa. Especially, fish has been identified as one of the best ecological indicators for an integrative health assessments in aquatic environments. In this preliminary study, the necropsy-based approach using the Health Assessment Index (Adams et al., 1993; HAI, Blazer, 2000), was employed for the assessments of aquatic environments influenced by effluent water from wastewater disposal plants (WDP) near a urban stream (i.e., Cap-Stream). For the impact analysis from the effluents, we developed 10 metric necropsy-based model including $M_l\;skin,\;M_2\;fin,\;M_3\;thymus,\;M_4\;spleen,\;M_5\;hindgut,\;M_6\;kidney,\;M_7\;liver.\;M_8\;eyes,\;M_9\;gill,\;and\;M_{10}$ pseudobranch. We set up duplicate controls (natural upstream water plus 5 fishes in each control tank) and duplicate treatments (effluent water from the WDP plus 5 fishes in each treatment tank) in the laboratory. Preliminary results showed that HAI values in the controls were zero, indicating an excellent condition by the criteria of HAI, while the HAI values in the treatments ranged between 40 and 150, indicating a poor condition. Also, various health conditions, based on the index of biological integrity (IBI), species richness, tolerance guilds, and trophic guilds supported the HAI approach. The HAI approach, not applied in Korea, not may be used as an surrogate fer ecological health assessment in lotic ecosystems.

Removal of Nitrogen and Phosphorus by Salix gracilistyla Miq. (갯버들(Salix gracilistyla Miq.)의 질소와 인 제거능)

  • 신정이;차영일
    • Korean Journal of Environmental Biology
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    • v.17 no.4
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    • pp.449-457
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    • 1999
  • Removal efficiency and potential of N and P by Salix gracilistyla Miq. are determined in continuous flow tanks as a function of hydraulic retention time (HRT, days) and nutrient concentration (NC). Results show that the removal efficiency was longer HRT and lower nutrient solution. And also removal potential was higher at shorter HRT and higher nutrient concentration, and the regression equations were estimated. Mean above ground biomass of Salix gracilistyla Miq. in the middle reaches of Suip stream was 4880.81 g/$m^2$, and estimated removal by this vegetation from biomass and estimated equation above were 0.49~15.49 NH$_4$-N kg/day, 5.83~405.39 NO$_3$-N kg/day, 7.57~23.22 PO$_4$-P kg/day in Suip stream, respectively when HRT was 0.59~5.21, inflow concentration was 0.05~0.4, mg/L NH$_4$-N, 1.42~11.36 mg/L NO$_3$-N, 0.1~0.27 mg/L PO$_4$-P. According to this study, it is concluded that Salix gracilistyla Miq. are contribute by their high biomass and for water quality improvement of stream through nutrient removal potential.

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Probable Volcanic Flood of the Cheonji Caldera Lake Triggered by Volcanic Eruption of Mt. Baekdusan (백두산 화산분화로 인해 천지에서 발생 가능한 화산홍수)

  • Lee, Khil-Ha;Kim, Sung-Wook;Yoo, Soon-Young;Kim, Sang-Hyun
    • Journal of the Korean earth science society
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    • v.34 no.6
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    • pp.492-506
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    • 2013
  • The historical accounts and materials about the eruption of Mt. Baekdusan as observed by the geological survey is now showing some signs of waking from a long slumber. As a response of the volcanic eruption of Mt. Baekdusan, water release may occur from the stored water in Lake Cheonjii caldera. The volcanic flood is crucial in that it has huge potential energy that can destruct all kinds of man-made structures and that its velocity can reach up to 100 km $hr^{-1}$ to cover hundreds of kilometers of downstream of Lake Cheonji. The ultimate goal of the study is to estimate the level of damage caused by the volcanic flood of Lake Cheon-Ji caldera. As a preliminary study a scenario-based numerical analysis is performed to build hydrographs as a function of time. The analysis is performed for each scenario (breach, magma uplift, combination of uplift and breach, formation of precipitation etc.) and the parameters to require a model structure is chosen on the basis of the historic records of other volcanos. This study only considers the amount of water at the rim site as a function of time for the estimation whereas the downstream routing process is not considered in this study.

Types of Green Landscapes in a Suburban City Perceptions of Local Residents (근교도시의 녹지경관 유형에 따른 지역주민의 경관인식)

  • Son, Yong-Hoon;Yoon, Moon-Young
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.5
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    • pp.101-110
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    • 2011
  • The objective of this study is to classify the characteristics of green landscapes in suburban cities and identify methods for managing them. The study site is Matsudo city in the outskirts of Tokyo, Japan. All the greenery in Matsudo was categorized into different landscape patterns using spatial analysis and field surveys. Afterwards, assessments of green landscapes were conducted using questionnaire surveys and factor analyses. There are a variety of green landscapes in Matsudo, formed by a number of different reasons such as urban planning, topographical characters and socio-cultural environments. Twenty different green landscape patterns were identified in Matsudo. The survey concluded that green landscape patterns of parks and rivers in Urbanization Control Areas are more attractive than patterns of farmland or forest in residential areas. Three major factors influenced perceptions: legibility, intimacy and the locality on the landscape assessment. Urban farmland and urban forest are two characteristics of suburban cities, and these green landscapes relate to intimacy or localities in a regional image. Finally, based on the results of this study, some implications were discussed for a green master plan and green landscape management.

The derivation of GIUH by means of the lag time of Nash model (Nash 모형의 지체시간을 이용한 GIUH 유도)

  • Kim, Joo-Cheol;Yoon, Yeo-Jin;Kim, Jae-Han
    • Journal of Korea Water Resources Association
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    • v.38 no.10 s.159
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    • pp.801-810
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    • 2005
  • The lag time is one of the most important factors for estimating a flood runoff from streams. It is well known to be under the influence of the morphometric properties of basins which could be expressed by catchment shape descriptors. In this paper, the notion of the geometric characteristics of an equivalent ellipse proposed by Moussa(2003) is applied for calculating the lag time of geomorphological instantaneous unit hydrograph(GIUH) at the basin outlet. The lag time is obtained from the observed data of rainfall and runoff by using the method of moments suggested by Nash(1957), and the procedure based on geomorphology is used for GIUH. The relationships between the basin morphometric properties and the hydrological response are discussed as applied to 3 catchments In Korea. Additionally, the shapes of equivalent ellipse are examined how then are transformed from upstream area to downstream one. As a result, the relationship between the hydrological response and descriptors is shown to be comparatively good, and the shape of ellipse is presented to approach a circle along the river downwards. These results may be expanded to the estimation of hydrological response of ungauged catchment.

Effects of Sewage Irrigation on Rice Growth Condition in Paddy Soil (오수유입수 관개가 벼 생육환경에 미치는 영향)

  • Kim, Jong-Gu;Lee, Kyeong-Bo;Park, Chan-Won;Lee, Deog-Bae;Kim, Seong-Jo
    • Korean Journal of Environmental Agriculture
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    • v.24 no.2
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    • pp.180-184
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    • 2005
  • This study was peformed to assess environmental effect through rice culture with sewage irrigation using Iksan stream water from 2002 to 2003. Contents of $NH_4-N$ in irrigation water keep up one day at the tillering stage and panicle formation stage were decreased 40% and 52% respectively, but that of continued 4 days was decreased $88%{\sim}98%$. The $NH_4-N\;and\;NO_3-N$ in run off by reduction 50% fertilization were more decreased 17% and 44% respectively, than those of conventional fertilization level. Amount of K and $NO_3-N$ loss in infiltration water were more decreased 18% and 4% respectively, those of than conventional fertilization level. The Cu and Pb contents in soil of after experiment were slightly increased but other heavy metals were not accumulated. The rice yield by reduction 50% fertilization level was not significant compare with conventional fertilization level but head rice rate was increased.

The development of land use planning technique applying low impact development and verifying the effects of non-point pollution reduction : a case study of Sejong city 6 district (저영향개발(LID)을 적용한 토지이용계획 기법 개발 및 적용효과 분석 : 세종시 6생활권을 대상으로)

  • Kang, Ki-Hoon;Lee, Kyung-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.7
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    • pp.548-553
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    • 2017
  • The aim of this study was to develop a low impact development design technique that can be applied in the land use planning stage and verify quantitatively the effects of non-point pollution reduction. For this purpose, the low impact development design elements that can be applied in the land use planning stage were derived and applied to an actual site, and the non-point pollution reduction effect was analyzed using the LIDMOD2 program. The analysis showed that the permeability rate of the land use plan using low impact development decreased by 19.8% compared to the existing land use plan. In addition, annual surface runoff decreased by 19.0% and annual infiltration increased by 164.1%. In the case of non-point pollution, the annual loading, T-N, T-P, and BOD decreased by 18.7 ~ 22.8%. Therefore, compared to the existing land use plan, the land use plan using low impact development has a considerably large effect of reducing the non-point pollution without changing the floor area according to each application. Therefore, to maximize the reduction effect of non-point pollution, it will be necessary to establish a related plan by applying the low impact development technique from the land use planning stage to the existing LID facility-oriented plan.

Characteristics of the Dangsan Forests at Ijeon-ri, Cheongsong-gun and Perspectives on Conservation Scheme (청송군 이전리 당산숲의 경관 특성 및 보전 방안)

  • Choi, Jai-Ung;Kim, Dong-Yeob;Rhee, Sang-Young
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.2
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    • pp.106-115
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    • 2014
  • Traditional village forests called Dangsan forests represent unique cultural landscape as a national cultural asset in Korea with a history of more than several hundred years. Cultural heritage can retain their value when they are fully sustained their authenticity and management scheme. The Dangsan forests established in a large area have been designated as a natural monument by Cultural Heritage Administration. Small scale Dangsan forests, however, are not introduced to the public and on the verge of disappearance. Dangsan forests have a value as a core landscape element in rural landscapes of Korea. The two villages at Ijeon-ri, Cheongsong-gun have small Dangsan forests where Dangsan ritual is performed. At one of the villages, there is Jusanji Reservoir designated for Scenic Site # 105, from which the water is used for growing crops. In this study, the landscape characteristics of the Dangsan forests were investigated including rice paddy field, stream, and the Jusanji Reservoir. A conservation measure of rural landscape for sustainable management scheme was suggested by designating 'Conservation area of agricultural landscape ecology'. Dangsan forests, especially where they are in small scale like those of Ijeon-ri, tend to be neglected. The Dangsan forests ought to be recognized for their value and by providing a management scheme including neighborhood elements such as farm fields and streams they can be revitalized to be core areas for conservation of rural landscape.

Policy for Establishment of Green Infrastructure (녹색 인프라 구축을 위한 정책)

  • Park, Jae-Chul;Yang, Hong-Mo;Jang, Byoung-Kwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.5
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    • pp.43-50
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    • 2012
  • The Green Infrastructure Framework refers to an interconnected network formed by greenways that links gardens, parks, green spaces, streams, wetlands, agricultural lands, and green belts. Green infrastructure supports diverse functions to environment, provides various benefits to people, and helps in the community's health and viability. It can store stormwater runoff and abate its non-point source pollutants. Due to its advantages and profits, advanced countries in environment policies have adopted green infrastructure in planning and implementing urban and regional development. The Korean government and municipalities have focused upon grey infrastructure investment in the past, which causes occurrence of natural disasters such as draught, flood, and landslides, degradation of water and air quality, decline of biodiversity, and even inhibition of economic activities. In order to alleviate these problems, it is requested to formulate and implement policies for green infrastructure at the national government level. USA and Korean situation of green infrastructure were investigated; forty components of green infrastructure were drawn. Nine policies utilized in the USA cases were identified, which are applicable to Korea. Among them, five policies can be implemented in public sector and four in private one. The green infrastructure law needed in Korea was suggested. The amendments of laws regarding green infrastructure and alternatives expending it were proposed.

Availability test of eco-levee construction for presevation of bangudae petroglyphs (생태제방을 이용한 반구대암각화 보존방안 연구)

  • Lee, Seung-Oh;Chegal, Sun-Dong;Cho, Hong-Je
    • Journal of Korea Water Resources Association
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    • v.49 no.11
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    • pp.931-939
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    • 2016
  • Bangudae Petroglopys of the national treasure No. 285 located in elevation of 53 m to 57 m have been damaged by repetition of submergence and exposure due to the Sayeon-dam of EL.60 m constructed in down stream. In this study, as a preservation plan of the petroglyphs from the contact with water, the construction of eco-levee was suggested and its effect was investigated in the views of hydraulic engineering. It was designed to be located aside of 80 m from Bangudae Petroglyphs with the length of 440 m in streamwise direction, and it was need to construct a new channel maintaining the original hydraulic capacity and conveyance. Hydraulic characteristics such as water surface elevations and velocities near Bangudae Petroglyphs were measured after the eco-levee was installed in the hydraulic model with the scale of 1:50. It showed that there were not much changes of water surface elevations and velocities between sayeon-dam spillway EL. 60 m (Suggestion 1) and EL. 54 m (Suggestion 2). It was concluded the eco-levee could be made of natural materials like soil, pebble, gravel in terms of allowable velocity and shear stresses. The slope of water surface at Suggestion 2 was steeper, and velocities near Bangudae Petroglyphs were also faster than Suggestion 1. As the vorties occured at the left side in Suggestion 2, more detailed study is required.