• Proceedings of the Korea Water Resources Association Conference
• /
• 2016.05a
• /
• pp.463-463
• /
• 2016

최근 도시물순환 복원 및 치 이수효과 증대를 위해 저영향개발기법(Low Impact Development) 연구가 활발하게 진행 중이다. 하지만 대부분이 수치모델을 활용한 설계프로그램 개발에 대한 연구에 집중되어 있는 실정이며, 이러한 프로그램을 활용한 설계 시 최적의 매개변수 결정에 한계가 있다. 이러한 이유로 본 연구에서는 건축형 LID 요소 중 하나인 식생여과장치(Planter Box)의 모형실험을 통해 프로그램 모의에 필요한 매개변수를 추정하고, 모의를 수행한 후 모형실험 결과와 프로그램 모의 결과를 비교하여 최종적으로 식생여과장치의 설계 매개변수를 산정하고자 한다. 식생여과장치의 모형실험을 위하여 가로 1.5m, 세로 1.5m, 높이 1.5m로 실험 장치를 제작하였으며, 강우-유출수 실험 전 시료의 침투율, 함수비 등을 체크한 후 지속시간 1시간의 재현빈도 5년, 10년, 20년, 50년에 해당하는 강우강도에 대해 실험을 수행하였다. 실험결과로 나타난 자료는 SWMM 모형과 비교분석해 모형에 적용된 매개변수의 적합성을 분석하였으며, 재현빈도 5년, 10년, 20년의 경우 $R^2$ 값이 0.88~0.97로 실험 값과 모의 값의 연관성이 높게 나타났으며, 재현 빈도 50년의 경우 0.7835로 비교적 연관성이 낮게 나타났다.

• Journal of the Korean GEO-environmental Society
• /
• v.6 no.2
• /
• pp.21-30
• /
• 2005

The purpose of this study was to evaluate the effect of vegetation on the cutting slope applied by vegetation system in the whole land. The engineering characteristics of slopes were investigated using the face mapping and physical tests. From the statistical methods, a relationship between a geologic stratum and degree of covering was independent. Therefore, the afforestation of slope was affected more by condition of vegetation as direction and opening of joints, and a topsoil state than by conventional classification of layer. It was concluded that the adjustable vegetation on the slope considering condition of geometric shape of slope, joint data and spontaneous type could make useful early afforestation.

• Ecology and Resilient Infrastructure
• /
• v.1 no.2
• /
• pp.68-81
• /
• 2014

In this study, the numerical simulation regarding the process and characteristics of topography change due to the vegetation recruitment and growth was carried out by adding the vegetation growth model to two-dimensional flow and sediment transport models. The vegetation introduction and recruitment on the condition for developing an alternate bar reduced the bar migration. The vegetated area and channel width changes were more significantly influenced by changes in upstream discharge rather than the duration of low flow. When the upstream discharge decreased, the vegetation area increased and the channel width decreased. The vegetation introduction and recruitment on the condition for developing a braided channel significantly influenced the characteristics of topography changes. In the braided channel, vegetation reduced the braided index, and when the upstream discharge decreased significantly, the channel topography was changed from the braided channel to the single channel. The vegetation area decreased as the upstream discharge increased. The channel width decreased significantly after the vegetation was introduced and it also decreased as the upstream discharge decreased. It was confirmed through the numerical simulation that a decrease in flood discharge accelerated the vegetation introduction and recruitment in the channel and this allowed to confirm its influence on the characteristics of topography changes qualitatively.

• Ecology and Resilient Infrastructure
• /
• v.4 no.1
• /
• pp.3-11
• /
• 2017

In this study, change in vegetation on bars was analyzed using the data on hydrology and river morphology with on-site photographic monitoring data for the sites of interest of the Naeseong Stream during the period from March 2013 to July 2016 when the impoundment of Yeongju Dam began. The effect of flow condition on burial and removal of vegetation covered on bar surfaces was elucidated by comparison of on-site photographic monitoring data with continuous water level plotted with on the cross-section profile. In 2014 burial happened due to late flood, while July flood caused burial and removal in 2016. On the contrary vegetation increased in 2015 due to low flow without flood. Results of this study showing natural changes in vegetation will be reference to changes which is expected to be caused by dam impoundment.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.49 no.2
• /
• pp.83-89
• /
• 2012

Natural Vegetation cover, which is very important earth resource, has been significantly altered by humans in some manner. Since this has currently resulted in a significant effect on global climate, various studies on vegetation environment including forest have been performed and the results are utilized in policy decision making. Remotely sensed data can detect, identify and map vegetation cover change based on the analysis of spectral characteristics and thus are vigorously utilized for monitoring vegetation resources. Among various vegetation indices extracted from spectral reponses of remotely sensed data, NDVI is the most popular index which provides a measure of how much photosynthetically active vegetation is present in the scene. In this study, for change detection in vegetation cover, a Multi-layer Perceptron Network (MLPN) as a nonparametric approach has been designed and applied to MODIS/Aqua vegetation indices 16-day L3 global 250m SIN Grid(v005) (MYD13Q1) data. The feature vector for change detection is constructed with the direct NDVI diffenrence at a pixel as well as the differences in some subset of NDVI series data. The research covered 5 years (2006-20110) over Korean peninsular.

• Ecology and Resilient Infrastructure
• /
• v.7 no.2
• /
• pp.90-96
• /
• 2020

Recently, a method that applies laser scanning (LS) that acquires vegetation information such as the vegetation habitat area and the size of vegetation in a point cloud format has been proposed. When LS is used to investigate the physical shape of vegetation, it has the advantage of more accurate and rapid information acquisition. However, to examine uncertainties that may arise during measurement or post-processing, the process of adjusting the data by the actual data is necessary. Therefore, in this study, the physical structure of stems, branches, and leaves of woody vegetation in an artificially formed river channel was manually investigated. The obtained results then compared with the information acquired using the three-dimensional terrestrial laser scanning (3D TLS) method, which repeatedly scanned the target vegetation in various directions to obtain relevant information with improved precision. The analysis demonstrated a negligible difference between the measurements for the diameters of vegetation and the length of stems; however, in the case of branch length measurement, a relatively more significant difference was observed. It is because the implementation of point cloud information limits the precise differentiation between branches and leaves in the canopy area.

• Korean Journal of Remote Sensing
• /
• v.25 no.5
• /
• pp.399-409
• /
• 2009

Many researches have shown that NDVI provides a potential methods to derive meaningful metrics that describe ecosystem functions. In this paper we investigated the use of the MODIS NDVI (Normalized Difference Vegetation Index) to monitor vegetation phenology dynamics of Northern plateau region, North Korea, during last 9-years (2000~2008). The findings of this paper can be summarized as follows. First, the length of growing season ranged from a low of 128 days in 2003 to a high of 176 days in 2000 and 2005. On the average of the last 9 years, the highest NDVI of 0.86 was marked on 28 July. Greenup onset occurs at the start of May, while the senescence begins between late September and October. Second, these annual vegetation cycles were compared with Seorak and Jiri Mountain regions of South Korea which have similar vegetation condition. Greenup onsets in South Korea were observed earlier than those of North Korea and the average time lag between the South and North Korea in Greenup was about 16 days which is a time-resolution of remotely sensed data. Sub-alpine conifers of such areas may be severely affected by the large of phenological characteristics due to the global warming trend.

• Korean Journal of Environment and Ecology
• /
• v.26 no.3
• /
• pp.437-445
• /
• 2012

The study performed the implementation monitoring of the revegetation methods applied to the test-bed of Simgok Stream in Incheon to identify the effect of water level and inundation period on the vegetation coverage of the stream bank revegetation methods. The categories of monitoring included the plant species and plant coverage for each method, physicochemical property of soil, water level and water quality. The result of monitoring revealed that plant growth conditions of all revegetation methods of each stream bank were good in the first survey as of May 2010. However, in the second survey of June 2011 when inundation period was less than a week, plant growth conditions and coverage of revegetation methods were partially bad. In the third survey as of August 2011 when inundation period was longest as 8 weeks during survey period, most vegetations did not survive except for Phragmites communis. But plant species number and plant coverage were increased gradually in the forth survey as of October 2011 when inundation period was less than 2 weeks so water level decreased more than that of third survey. Accordingly, the correlation analysis among number of plant species and plant coverage on stream bank, which applied revegetation method, water level and inundation period was performed for quantitative analysis. The result revealed that number of plant species and plant coverage has a negative correlation with water level and inundation period, but inundation period had higher correlation with plant occurrence than water level.

• Ecology and Resilient Infrastructure
• /
• v.3 no.4
• /
• pp.322-326
• /
• 2016

The distribution of floodplain vegetation is mainly affected by hydrological and hydraulic processes. In this study, we investigated changes in the vegetation distribution due to flood discharge alteration, and the relationship between the vegetation types and the flood frequency during the last ten-year period in the Cheongmi-cheon Stream. Flood discharge of the Cheongmi-cheon Stream tended to decrease from 2006 to 2016. It has greatly decreased to less than $160m^3/s$ since 2013. This resulted in the settlement of Phragmites japonica to the wide sand bar at the Cheongmi-cheon Stream, even though it had sparse vegetation before 2013. The sand bar was fully covered with P. japonica in 2016. Vegetation communities in the floodplain were classified by dominant species, i.e. the annual-hygrophytic, the perennial hygrophytic and the mesophytic communities. Analysis of the relationship between the vegetation communities and the flood frequency shows the annual hygrophytes, perennial hygrophytes and the mesophytes communities distributed in the range of under 1 year, 1-10 year and over 7 year flood inundation area, respectively. In conclusion, distribution of the floodplain vegetation is closely related with the flood discharge and frequency in the Cheongmi-cheon Stream.

• Ecology and Resilient Infrastructure
• /
• v.3 no.1
• /
• pp.70-75
• /
• 2016

The purpose of this study was to develop water-purification vegetation mats consisting of the eco-friendly materials and to validate their water purification capabilities with the objective of reducing nonpoint pollution into streams. The developed vegetation mats are made of coconut fiber shell and filling consisted of zeolite, diatomaceous earth or a mixture of calcinated foam media. The bench scale assessment of the water purification capability of the three filling materials showed that the removal efficiencies of suspended solid (SS), total nitrogen (T-N) and total phosphorus (T-P) were higher in the foam media than in zeolite or diatomaceous earth. From the results of the field experiment, the removal efficiencies of the vegetation mats filled with the foam media were 60.1% in SS, 32.2% in T-N and 20.2% in T-P. Therefore the vegetation mats filled with the foam media calcinated from zeolite and diatomaceous earth should have higher efficiencies in controlling the nonpoint source pollutions in streams.