• 환경영향평가
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• 제13권3호
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• pp.137-151
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• 2004

Many of today's environmental problems are regional in scope and their effects overlap and interact. The purpose of this paper is to developed a simple method for an integrated assessment of environmental conditions across the Mid-Nakdong River Region, by combining data on land use, impervious cover, roads, streams, riparian areas, forest patches, population, pollutant loadings, soil erosion and topography. A cluster analysis was used to identify groups of sub-watersheds with similar environmental characteristics. The mean value for each group was used to find watershed that may be more vulnerable to future environmental degradation. Watersheds in cluster I and II had high amount of forest, but the amount of riparian vegetation was low. Watersheds in cluster III, which located in the middle Geumho River and the main course of Nakdong River, had a greater proportion of their agriculture, a greater proportion of agriculture on steep slopes, and less forest adjacent to streams. Watersheds in cluster IV and V were in the most urbanized areas of the region. The principal adverse impacts for watersheds in this group were high scores for urban area, impervious cover, pollutant loadings, population density, forest fragmentation, and low amounts of forest and riparian forest cover. Notwithstanding the exploratory nature of cluster analysis, it appears to be a useful tool for grouping watersheds with similar environmental characteristics.

• 한국농공학회논문집
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• 제52권3호
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• pp.65-71
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• 2010

This study was conducted to investigate the dynamics of nutrients such as total nitrogen (TN), nitrate nitrogen ($NO_3$-N) total phosphorous (TP), and phosphate phosphorous ($PO_4$-P) in outflow from a cabbage farmland in a mixed land-use watershed. The TN concentrations in groundwater showed twice peaks in late July 2006 and late March 2007 (3.8, 4.7 mg/L, respectively), when it rained shortly after fertilizer application, indicating that nitrogen leaching is greatly influenced by fertilization and rainfall. The mean concentrations of TN and $NO_3$-N in surface water were not significantly higher than those in groundwater, while the mean concentrations of TP and $PO_4$-P in surface water were significantly (p < 0.05) were higher than those in groundwater. The TN concentrations in groundwater were generally higher than those in surface water during fertilization and early growing season due to the effect of fertilization, but vice versa in the other periods. In contrast, the TP concentrations in groundwater were always lower than those in surface water due to the sorption of particulate phosphorous by soil. The ratio of TN load in baseflow to that in total TN load (39 %) was much greater than the TP ratio (7 %), suggesting that baseflow contribute to nitrogen export. Therefore, proper fertilization management should be taken to reduce nitrogen load through baseflow.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권12호
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• pp.6190-6213
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• 2019

For small-scale vector data, restrictions on watermark scheme capacity and robustness limit the use of copyright protection. A watermarking scheme based on robust geometric features and capacity maximization strategy that simultaneously improves capacity and robustness is presented in this paper. The distance ratio and angle of adjacent vertices are chosen as the watermark domain due to their resistance to vertex and geometric attacks. Regarding watermark embedding and extraction, a capacity-improved strategy based on quantization index modulation, which divides more intervals to carry sufficient watermark bits, is proposed. By considering the error tolerance of the vector map and the numerical accuracy, the optimization of the capacity-improved strategy is studied to maximize the embedded watermark bits for each vertex. The experimental results demonstrated that the map distortion caused by watermarks is small and much lower than the map tolerance. Additionally, the proposed scheme can embed a copyright image of 1024 bits into vector data of 150 vertices, which reaches capacity at approximately 14 bits/vertex, and shows prominent robustness against vertex and geometric attacks for small-scale vector data.

• 한국시스템다이내믹스연구
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• 제7권1호
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• pp.91-118
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• 2006

The purpose of this study is to find what factors are directly related to the delay of public projects, usually going beyond the planned deadline and budget. From a series of System Dynamics simulation works applied to the Cheongju Cremation Project, the research finds that the negative externalities originated from the adjacent location of the LULU(locally unwanted land use) facilities have exerted significant influence on dynamic perceptions of key stakeholders, typically resulting in project delay. As shown repeated experiments, the proposed negotiation-based models would produce relatively higher planning performance level than the typical approaches hinged on the administrative-expediency tactics. Even though the former may require more human and material resources in the very beginning stage, as they have to deal with diverse grievances raised by major stake-holders, most of them would bound for strengthening reinforcing loops within the complex structure. These results also imply that negotiation or consensus-building approaches would enhance mutual agreement among stake-holders, upgrading the overall quality of project management.

• 한국환경복원기술학회지
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• 제15권2호
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• pp.19-29
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• 2012

Numerous studies suggested that fish assemblage structure reflects the status of stream ecosystems. The status of streams integrity, including various trophic levels, water quality and habitat degradation, can be assessed by fish assemblages. In this study, we investigated the relationships between fish assemblages and streamline geometry of streams. Previous studies suggested that geomorphologic parameter can be a critical factor of permeability between adjacent two systems. From a landscape ecological perspective, edges may partially control the flow rate of energy between two adjacent systems. Thus, the Streamline geometry can be a geomorphologic parameter that exhibits the integrity of stream. We selected the Nakdong river for study areas, which is one of major rivers and the longest (525 km) River in South Korea. We used the revised IBI representing overall ecological characteristics of Korean fish assemblages and eight sub-assessment criteria of IBI, collected from 82 sampling sites in the Nakdong River. For calculating the Streamline geometry, we measured fractal dimension index that generally used in biology, ecology and landscape ecology. We used the digital land-use/land-cover map and generated a 1-km buffer for each sampling site and refined the shape of the Streamlines. Pearson correlation analyses were performed between Streamline geometry and IBI and sub-assessment criteria of IBI. The results show that IBI and eight sub-assessments of fish are significantly correlated with geometry of Streamline. The fractal dimension of Streamline geometry were related with IBI (r = 0.48) and six sub-assessments of IBI, including total number of native fish and native species, the number of riffle benthic species, sensitive species, tolerant species and native insectivore. Especially, the number of tolerant species(r = -0.52) and native insectivore(r = 0.52) show strong correlation with geometry of Streamline. These results indicate that lower Streamline geometry can result in poor fish assemblages, while higher geometry of Streamline can enhance fish assemblages by potentially supplying insects and better habitat conditions. We expect the results of our study to be useful for stream restoration and management. However, we see the necessity of study investigating the mechanisms how Streamline geometry affect fish assemblages.

• Journal of Ecology and Environment
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• 제35권2호
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• pp.123-129
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• 2012

Salt marsh is an important transitional zone among terrestrial, riverine, and marine ecosystems and is a productive habitat that interacts extensively with adjacent landscape elements of estuarine and coastal ecosystems. Nowadays, in addition to various human activities, a variety of natural processes induce changes in salt marshes. This study aims to provide background information to restore disturbed salt marshes and to propose their ecological restoration using seed banks. The study area is a prepared area for the Gwangyang Container Port located in the southern Korea. This area was formed by accumulating mud soils dredged from the bottom of the forward sea. This land was created in a serial process of preparing the Gwangyang container port and the salt marsh was passively restored by seeds buried in mud soil dredged from seabed. As a result of stand ordination based on vegetation data collected from the land, stands were arranged according to tolerance to salinity in the order of $Suaeda$ $maritima$, $Salicornia$ $europaea$, and $Phragmites$ $communis$ communities on the Axis 1. Landscape structure of the projected area was analyzed as well. Edges of the projected area were divided from the marginal waterway by the dike. Four types of vegetation appeared on the dike: $Alnus$ $firma$ plantation, $Robinia$ $pseudoacacia$ plantation, $Lespedeza$ $cyrtobotrya$ plantation, and grassland. In the more internal areas, two types of vegetation sequences appeared: $Aster$ $tripolium$ community-$Suaeda$ $glauca$ community-$Salicornia$ $europaea$ community sequence and $Aster$ $tripolium$ community-$Suaeda$ $maritima$ community-$S.$ $europaea$ community sequence. Mixed community showed the highest species diversity (H' = 0.86) and $S.$ $europaea$ community showed the lowest (H' = 0.0). Evenness is the highest in Mixed community (J' = 2.26) and the lowest in $S.$ $maritime-S.$ $europaea$ community (J' = 0.0). Several plant communities were successfully established on the land created by mud soil dredged from the bottom of Gwangyang Bay. Moreover, community diversity in this area approached a similar level with those from other studies involving natural salt marshes. Therefore, restoration effect based on community diversity obtained in our study can be evaluated as a successful achievement. In this respect, although most salt marshes in Korea and other places worldwide have been destroyed or disturbed by excessive land use, feasibility of seed bank as a restoration tool is greatly expected.

• Ecology and Resilient Infrastructure
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• 제7권3호
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• pp.160-170
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• 2020

철도와 도로는 대표적인 선형사업으로, 전국적으로 철도망과 도로망이 확대되고 있는 추세이며, 환경에 미치는 영향을 최소화하기 위해 철도와 도로의 평행노선에 따른 생태계 단절을 최대한 지양하고 있다. 본 연구에서는 우선적으로 철도와 도로개발 시, 환경에 미치는 영향을 살펴보기 위한 각 사업의 중점평가항목에 대한 비교·분석을 통해 차이점과 특징을 고찰하였다. 그 결과, 도로 개발은 철도사업과는 달리 효율적인 토지이용계획 수립에 대한 사항과 토양 보호를 중점평가항목으로 제시하고 있다. 본 연구에서는 철도 노선이 도로와 인접하게 될 때의 환경적 영향을 살펴보기 위한 구체적인 평가 항목과 기준이 제시되어 있지 않음에 따라, 관련 문헌을 검토하여 총 8개 평가 항목을 제시하였다. 특히, 계획의 적정성과 입지타당성을 살펴보기 위한 전략환경영향평가 단계에서 기존의 도로에 철도가 인접하게 될 때 미치는 환경적 영향을 사전에 검토할 수 있는 이격거리 기준을 제안하고자, 기 운영 중인 철도 노선을 대상으로 도로와의 이격거리를 살펴보았으며, 환경생태적 영향을 최소화하기 위해 검토해야 할 이격거리로 200 m 이내일 것을 제시하였다. 본 연구 결과는 철도와 도로가 인접할 때 환경생태적 영향을 최소화할 수 있는 대안노선을 검토하는 사업계획 단계에서 근거 자료로 활용될 수 있을 것이다.

• 농촌계획
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• 제6권1호
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• pp.29-37
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• 2000

The purpose of this study was to propose section designs for the ecological improvement of streams in rural villages in Korea. According to the survey about ecological conditions of rural streams of 10 selected rural villages (sep., 1996), the streams could be classified into three divisions(upstream, inner village, downstream), and the average width of streams was 9m, and the height of banks 3.1m. The slopes of basin were 7.33%, 2.67%, 1.39% at upstream, inner village, downstream respectively. The survey about the residents' usage of stream and the preferred activities(jun., 1997) showed that the streams were most frequently used for the supply of agricultural water use(39%), for the washing(15%) and for the recreation and rippling(10%), etc.. Three standard designs were presented for upstream, inner village, and downstream, and three standard sections were made by each designs. For the upstream division, it was designed to be used for the recreational activities in summer and the major stream bank materials were base rock and existing boulders with least artificiality. As the streams in the residential area were expected to be frequent access and used by the residents, most facilities for the streamside activity such as waterfront, water holes, shallows, walk were concentrated in this part with some artificiality. The downstream was designed for the agricultural activities such as water supply, space for the preparation of work and some break during the work.

• 한국습지학회지
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• 제19권4호
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• pp.403-408
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• 2017

본 연구는 물새의 주요서식지인 한강의 물리적 구조 변화특성에 대한 시계열적분석을 실시함으로써 향후 물새서식지 복원 등 관리를 위한 기초자료를 구축하고자 하였다. 분석은 한강 전체 497.5km 중 서울 시내를 관통하는 구간인 상류부 팔당대교에서부터 하류부 행주대교까지 총 41.5km을 대상으로 하였고, 1975년을 기준하여 한강의 제외지를 대상으로 하였다. 토지이용분석결과, 1975년에는 퇴적지(22.7%), 수면(20.7%)을 포함하여 주변으로 시가화지역(16.9%), 밭(16.2%), 논(15.9%)이 주요 유형이었는데, 이후 대부분 지역의 토지이용을 위해 하천권역 내부로 간선도로가 조성되었고 수면 확대를 위해 수중보가 건설되면서 1985년에는 하천의 역할을 상실한 제내지(51.7%)가 급격히 증가하였다. 수면(32.8%)의 증가 또한 두드러졌으며, 제방의 축조와 수중보 조성 이후에는 토지이용의 급격한 변화보다는 조금씩 이용지역의 면적이 늘어나고 상대적으로 자연지역이 줄어드는 경향을 보였다. 2005년에는 제내지가 차지하는 비율이 57.7%까지 증가하였으며 수면은 33.3%로 증가하였다. 호안길이는 2005년 기준 1975년 대비 10.9% 감소하였으며, 자연호안의 길이는 91.5% 감소하였다. 반면 수심은 1.46m 증가한 것으로 분석되었다. 지난 30년간의 한강의 물리적 구조 변화의 흐름을 종합하면 1980년대 이전까지는 대규모 건설공사로 인한 수변구역의 축소와 수면부의 확장이 주로 진행되었으며 이후에는 호안의 인공화가 주로 진행된 흐름을 확인할 수 있었다. 서식처 측면에서 한강은 과거 다양한 서식환경을 유지하던 곳에서, 현재는 소수 물새류를 위한 단순한 서식지로 변화되어 서식처 다양성을 위한 적극적 개선이 필요한 것으로 판단되었다.

• 한국도로학회논문집
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• 제13권4호
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• pp.211-220
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• 2011

최근 대중교통지향형개발(TOD)이 활발해지며, 역세권의 환경 변화를 통하여 국내의 대중교통 이용 증진을 시키기 위해서는 TOD 통합계획요소를 종합적으로 고려한 역세권 유형과 이용수요에 관한 실증분석이 전제되어야 향후 계획수립시 활용이 가능 할 것이다. 본 연구는 서울시 역세권을 대상으로 다양한 TOD 영향요인을 파악하고, 대중교통 이용수요와 연관성을 규명하기 위한 실증분석을 진행하였다. TOD의 대표적 요소인 Density, Diversity, Accessibility에 대한 자료를 수집하고, 요인분석과 회귀모형을 구축하였다. 분석결과 (1) 요인분석을 토대로 7개 영향요인이 도출되었으며, Factor 1(Diversity/토지이용복합도 (LUM)), Factor 2(Density/개발밀도수준), Factor 3(Accessibility/대중교통시설공급수준), Factor 4(Design/가로설계수준), Factor 5(Green/연계교통시설(보행자, 자전거), Factor 6(Design/지하철시설규모), Factor 7(Accessibility/대중교통운영수준)로 유형화되었다. (2) 요인-회귀분석 결과를 토대로 역세권 승하차 인원에 긍정적(+) 영향을 미치는 주요 요인은 Factor 1(Diversity : 토지이용복합도(LUM) 요인), Factor 3(Accessibility : 대중교통시설공급수준), Factor 2(Density : 개발밀도수준), Factor 5(Design/연계교통시설(보행자, 자전거), Factor 6(지하철시설규모)로 나타났다. 다음으로 역세권의 승하차 인원에 부정적(-) 영향은 Factor 7(Accessibility/대중교통운영수준)로 나타났으며, 가장 높은 영향력을 가지는 것으로 나타났다. 이는 지하철과 버스의 배차간격이 증가할 경우 이용수요가 감소하기 때문이다.