• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.426-428
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• 2003

Optical and microwave remote sensing data have been widely used in land cover and land use classification. Thanks to the spectral absorption characteristics of ground object in visible and near infrared region, optical data enables to extract different land cover types according to their material composition like water body, vegetation cover or bare land. On the other hand, microwave sensor receives backscatter radiance which contains information on surface roughness, object density and their 3-D structure that are very important complementary information to interpret land use and land cover. Separate use of these data have brought many successful results in practice. However, the accuracy of the land use / land cover established by this methodology still has some problems. One of the way to improve accuracy of the land use / land cover classification is just combination of both optical and microwave data in analysis. In this paper for the research, the author used LANDSAT TM scene 127/45 acquired on October 21, 1992, JERS-1 SAR scene 119/265 acquired on October 27, 1992 and aerial photographs taken on October 21, 1992. The study area has been selected in Hanoi City and surrounding area, Vietnam. This is a flat agricultural area with various land use types as water rice, secondary crops like maize, cassava, vegetables cultivation as cucumber, tomato etc. mixed with human settlement and some manufacture facilities as brick and ceramic factories. The use of only optical or microwave data could result in misclassification among some land use features as settlement and vegetables cultivation using frame stages. By combination of multitemporal JERS-1 SAR and TM data these errors have been eliminated so that accuracy of the final land use / land cover map has been improved. The paper describes a methodology for data combination and presents results achieved by the proposed approach.

• Journal of Cadastre & Land InformatiX
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• v.46 no.2
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• pp.27-42
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• 2016

Forest accounts for almost 64 percents of total land cover in South Korea. For inventorying, monitoring, and managing such large area of forest, application of remote sensing and geographic information system (RS/GIS) technology is essential. On the basis of spectral characteristics of satellite imagery, forest cover and tree species can be classified, and forest cover map can be prepared. Using three dimensional data of LiDAR(Light Detection and Ranging), tree location and tree height can be measured, and biomass and carbon stocks can be also estimated. In addition, many indices can be extracted using reflection characteristics of land cover. For example, the level of vegetation vitality and forest degradation can be analyzed with VI (vegetation Index) and TGSI (Top Grain Soil Index), respectively. Also, pine wilt disease and o ak w ilt d isease c an b e e arly detected and controled through understanding of change in vegetation indices. RS and GIS take an important role in assessing carbon storage in climate change related projects such as A/R CDM, REDD+ as well. In the field of climate change adaptation, impact and vulnerability can be spatio-temporally assessed for national and local level with the help of spatio-temporal data of GIS. Forest growth, tree mortality, land slide, forest fire can be spatio-temporally estimated using the models in which spatio-temporal data of GIS are added as influence variables.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.85-99
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• 2017

The study was compared for ability to supply macro-nutrients between time and height of mowing to establish alternate technique of a chemical fertilizer with 9-year old 'Niitaka' pear (Pyrus pyrifolia Nakai) trees in a pesticide-free orchard in 2009. Rye and hairy vetch were sown together during fall 2008. Four types of mowing time treatments were included; mowing on April 18+May 28, on April 28+June 8, on May 8+June 18, and on April 18+May 18+June 18. Mowing height treatment included mowing at $3{\pm}1cm$, $7{\pm}1cm$, and $13{\pm}1cm$ on April 18 or June 8. Mowing on May 8+June 18 increased the most dry weight of ground cover and vegetation to 14,480 kg per ha among the mowing time treatments, resulting in the greatest production of T-N (total nitrogen; 292 kg) and K (396 kg) per ha on the soil. Mowing at $7{\pm}1cm$ decreased the most dry weight of ground cover and vegetation to 11,970 kg per ha among the mowing height treatments, resulting in the lowest production of T-N (265 kg), P (111 kg) and K (333 kg) per ha in a soil. Ground cover treatments increased soil organic matter contents, regardless of mowing treatment methods.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.144-154
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• 2017

The riparian vegetation is one of corridor type ecosystems, an ecotone and able to improve the ecological soundness by structural and functional link. And they act as habitats, sources and sinks of species, conduits, filters and barriers. This study was carried out to develop the vegetation model for the fluctuation areas of lake reservoirs consider of hydrologic and soil environments according to the vegetation structure of the reference ecosystem. To develop the case study, 2 sites within 10degree slope of the Daecheong Lake were selected. The riparian vegetation models were built by the results of GIS analysis, remote satellite analysis, field survey results, consider of water level, flooded frequency, soil and topographic index, land cover or land use etc. 1) study area varied from FWL to -5m of NFWL, 2) slope 10% below, 3) vegetations flooded below 100days yearly are Salix koreensis, Salix chaenomeloides, Salix gracilistyla, 4)land cover type classified wildlife grassland, abandoned paddy field, cropland according to landuse (or landcover), 5)finally model was constructed as ecological landscape forest. The model designs were suggested by 2 types in Daecheong lake reservoir. The model for the riparian vegetation corridors could be the basic and useful data to improve the ecological and landscape properties.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.121-128
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• 2011

Long-term water treatment performance analysis was conducted for the constructed wetland treating agricultural tailwater. Studied wetland was established in 2001 and operated from June, 2002 to November, 2010. Wetland vegetation cover was shown over 90 % coverage after 2005. According to vegetation development, accumulation of sediment nutrient was observed; Organic Carbon, T-P and T-N. In addition, DO concentration and temperature was decreased in the constructed wetland output. An infiltration rate also significantly decreased due to compaction of wetland soil. A runoff coefficient was increased due to the low infiltration rate after 2005. A T-N, TSS and Chl.a removal rate was maintained constantly. However, the T-P removal rate was slightly decreased along to wetland operation because low DO concentration could increase elution of phosphorus from sediment. After constructing open water, the T-P removal rate was increased. This is because open water could accelerate the reaearation process. Consequently, over three years of vegetation development could be helpful for wetland performance. In addition, DO concentration is important factor to maintain the T-P treatment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.17-26
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• 2005

Ecological corridor is the facility to connect two habitats fragmented by roads, dam, housing and industrial area. Critics of faunal corridors have suggested that they are simply an untested application of unproved island biogeography theory. But, everyone agree that ecological corridor is important useful structural components that help animal movement in fragmented landscapes. There are 52 ecological corridors in Korea. We investigated 43 ecological corridors of these and recorded the size of corridor, planting species, management and growth condition. We compared planting species to nearby exiting vegetation species and structure. We found that there are no considerations for many aspects of planting, for example, planting species, structure, animal migration and behavior, surrounding vegetation etc. Expecially, It was ignored management of plants, difference of surrounding vegetation, lacks of diverse planting species and structure. We suggest planting the native species of tall tree, shrub and ground cover, edge planting for transitional space between road and natural habitat, planting for foraging and breeding of target animal, diverse layer vegetation, and open space of center for rapid animal dispersal.

• Journal of Environmental Science International
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• v.14 no.8
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• pp.739-748
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• 2005

The purpose of this study is to analyze seasonal changes in structure and landscape of Gongji stream corridor in Chuncheon, and to suggest some guidelines to contribute to creating a desirable close-to- nature stream. The study seasonally surveyed floodplain and revetment conditions, channel micro-topography, streamflow level and velocity, and vegetational cover. Flooding, water level, and vegetation were major factors of affecting seasonal changes in streambed structure and stream landscape. Small sand bars and islands were considerably disturbed by flooding and water level change. However, large islands and sand bars in the upper and middle section of the study stream remained or reappeared even after flooding. Flooding also tended to repeat channel sedimentation at the same spot. Controlling water volume of the Euiam Lake, which is adjacent to the study stream, caused higher water level downstream in the dry seasons. The majority of vegetation in sand bars and islands was washed away by the floods. Vehicle passing, crop cultivation, and ball game were other elements which disturbed vegetation in the floodplain. Creating a close-to-nature stream should reflect micro-topographical changes of channel by flooding, prevent improper vehicle entry and human use, and remove concrete material in the revetment and floodplain.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.104-117
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• 1998

Rising concern about climate change has evoked interest in the potential for urban vegetation to help reduce the level of atmospheric CO\sub 2\, a major heat-trapping gas. This study quantified the functio of home energy savings and carbon emission reduction by shading, evapotranspiration and windspeed reduction of urban vegetatioin in Chuncheon. Tree and shrub cover averaged approximately 13% in residential land. The effects of shading, evapotranspiration and windspeed reduction annually saved heating energy by 2.2% and cooling energy by 8.8%. The heating and cooling energy savings reduced carbon emissions by 3.0% annually. These avoided emissions equaled the amount of carbon emitted annually from fossil fuel consumption by a population of about 1,230. Carbon emission reduction per residential building was 55kg for detached buildings and 872 kg for multifamily buildings. Urban vegetation annually decreased heating and cooling energy cost by ￦1.1 billions, which were equivalent to annual savings of ￦10,000 savings and carbon emission reduction due to tree plantings in the wrong locations, while windspeed reduction had a great effect. Plantings fo large trees close to the west and east wall of buildings, full tree plantings on the north, and avoidance of shade-tree plantings or selection of solar-friendlytrees on the south were recommended to improve the function of building energy savings and carbon emission reduction by urban vegetation.

• Journal of Wetlands Research
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• v.18 no.1
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• pp.84-93
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• 2016

As a transition region between ocean and land, coastal wetlands are significant ecosystems that maintain water quality, provide natural habitat for a variety of species, and slow down erosion. The energy of coastal waves and storm surges are reduced by vegetation cover, which also helps to maintain wetlands through increased sediment deposition. Wave attenuation by vegetation is a highly dynamic process and its quantification is important for understanding shore protection and modeling coastal hydrodynamics. In this study, laboratory experiments were used to quantify wave attenuation as a function of vegetation type as well as wave conditions. Wave attenuation characteristics were investigated under regular waves for rigid model vegetation. Laboratory hydraulic test and numerical analysis were conducted to investigate regular wave attenuation through emergent vegetation with wave steepness ak and relative water depth kh. The normalized wave attenuation was analyzed to the decay equation of Dalrymple et al.(1984) to determine the vegetation transmission coefficients, damping factor and drag coefficients. It was found that drag coefficient was better correlated to Keulegan-Carpenter number than Reynolds number and that the damping increased as wave steepness increased.

• Journal of Korea Water Resources Association
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• v.47 no.4
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• pp.321-330
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• 2014

This study was performed to investigate relation between riparian vegetation and environmental factor and to predict riparian vegetation succession in Nakdong river, which is typical sand river in Korea Peninsula. We searched 5 natural levee and installed 84 quadrats in Nakdong river near by Andong city. Also, We analyzed flora, vegetation cover degree, topography, soil moisture, organic content, pH, electrical conductivity and soil texture. According to the result of CCA (canonical correspondence analysis), which considered both investigated vegetation data and environmental factor, vegetation were divided down three groups, and each group was difference by height above ordinary water level, organic content and sand. In addition, the most powerful factor was indicated the height above ordinary water level.