• Title/Summary/Keyword: forest cover

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The Soil Loss Analysis using Landcover of WAMIS - for Musimcheon Watershed - (WAMIS 토지피복도를 활용한 토양유실량 분석 - 무심천 유역을 대상으로 -)

  • Kim, Joo-Hun;Lee, Chung-Dae;Kim, Kyung-Tak;Choi, Yun-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.4
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    • pp.122-131
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    • 2007
  • This study estimates how soil loss in a basin has been occurred according to the change of land cover, and analyzes which type of land cover has the largest soil loss by classifying the land-cover type into each area and a whole basin. Musimcheon, the second branch stream of GeumGang, is chosen as a research area. The result of analysis shows that the average soil loss occurs most largely in a crop land and a paddy field. The yearly soil loss of watershed estimates approximately 14,000 ton/yr in case of using 100-year-frequency rainfall data. A forest area, which takes the largest area in watershed, shows the soil loss occurs approximately 1,000ton/yr. A crop field shows that soil loss increased most largely 4,900 ton/yr (34.6%) in 1985 to 8,100 ton/yr (56.1%) in 2000. The change of land cover in a crop land increased 8% to 14%, and this change influences on the increase of soil loss. As a result of analyzing the area over $200ton/km^2/yr$, the soil loss in a crop field accounts for 74% to 96%.

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Improving Accuracy of Land Cover Classification in River Basins using Landsat-8 OLI Image, Vegetation Index, and Water Index (Landsat-8 OLI 영상과 식생 및 수분지수를 이용한 하천유역 토지피복분류 정확도 개선)

  • PARK, Ju-Sung;LEE, Won-Hee;JO, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.19 no.2
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    • pp.98-106
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    • 2016
  • Remote sensing is an efficient technology for observing and monitoring the land surfaces inaccessible to humans. This research proposes a methodology for improving the accuracy of the land cover classification using the Landsat-8 operational land imager(OLI) image. The proposed methodology consists of the following steps. First, the normalized difference vegetation index(NDVI) and normalized difference water index(NDWI) images are generated from the given Landsat-8 OLI image. Then, a new image is generated by adding both NDVI and NDWI images to the original Landsat-8 OLI image using the layer-stacking method. Finally, the maximum likelihood classification(MLC), and support vector machine(SVM) methods are separately applied to the original Landsat-8 OLI image and new image to identify the five classes namely water, forest, cropland, bare soil, and artificial structure. The comparison of the results shows that the utilization of the layer-stacking method improves the accuracy of the land cover classification by 8% for the MLC method and by 1.6% for the SVM method. This research proposes a methodology for improving the accuracy of the land cover classification by using the layer-stacking method.

Region of Interest (ROI) Selection of Land Cover Using SVM Cross Validation (SVM 교차검증을 활용한 토지피복 ROI 선정)

  • Jeong, Jong-Chul;Youn, Hyoung-Jin
    • Journal of Cadastre & Land InformatiX
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    • v.50 no.1
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    • pp.75-85
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    • 2020
  • This study examines machine learning cross-validation to utilized create ROI for classification of land cover. The study area located in Sejong and one KOMPSAT-3A image was used in this analysis: procedure on October 28, 2019. We used four bands(Red, Green, Blue, Near infra-red) for learning cross validation process. In this study, we used K-fold method in cross validation and used SVM kernel type with cross validation result. In addition, we used 4 kernels of SVM(Linear, Polynomial, RBF, Sigmoid) for supervised classification land cover map using extracted ROI. During the cross validation process, 1,813 data extracted from 3,500 data, and the most of the building, road and grass class data were removed about 60% during cross validation process. Based on this, the supervised SVM linear technique showed the highest classification accuracy of 91.77% compared to other kernel methods. The grass' producer accuracy showed 79.43% and identified a large mis-classification in forests. Depending on the results of the study, extraction ROI using cross validation may be effective in forest, water and agriculture areas, but it is deemed necessary to improve the distinction of built-up, grass and bare-soil area.

Effect of Calcium Chloride Concentration on Roadside Ground Cover Plant Growth (염화칼슘 처리농도가 가로변 지피식물의 생장에 미치는 영향)

  • Lee, Sun-Young;Kim, Won-Tae;Ju, Jin-Hee;Yoon, Yong-Han
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.4
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    • pp.17-23
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    • 2013
  • The purpose of this study was to provide information on management and apply it to a roadside ground cover plant understanding the capacity of calcium chloride in the plant. The experimental group was composed of the ratio control group of calcium chloride, 0.5%, 1.0%, and 3.0% in 500g of soil. Plant materials were selected and measured according to their ecological characteristics such as ground cover plant, Pachysandra terminalis, Hosta plantaginea, Trachelospermum asiaticum, Vitex rotundifolia, Euonymus japonica and Callicarpa japonica. The acidity of the amended soil was increased gradually depending on the treatment and conductivity was continually decreased. The EX-Ca increased after the treatment, but decreased in the middle of the experiment. Pachysandra terminalis, Trachelospermum asiaticum and Euonymus japonica were able to grow and survive at the ratio of 0.5%. Hosta plantaginea and Vitex rotundifolia were able to survive at the ratio of 1.0%. Hosta plantaginea, the possible state can absorb salts due to moisture and, can be applied to ground cover plants in the roadside. The growth and development of Callicarpa japonica was poor and the leaves were open to grow for calcium chloride treatment except the control group. It was concluded that Callicarpa japonica was very sensitive to calcium chloride.

Analysis of Impacts of Land Cover Change on Runoff Using HSPF Model (HSPF 모형을 이용한 토지피복변화에 따른 유출 변화 분석)

  • Park, Min-Ji;Kwon, Hyung-Joong;Kim, Seong-Joon
    • Journal of Korea Water Resources Association
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    • v.38 no.6 s.155
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    • pp.495-504
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    • 2005
  • The objective of this study is to estimate the impacts of land cover change on the runoff behavior using Hydrologic Simulation Program-Fortran (HSPF) model and Landsat images. Land cover maps were prepared using three every ten years from 1980 to 2000 of the upper watershed ($258\;km^2$) of Gyeongan stream. Hydrologic parameters of HSPF were calibrated using observed data (1999 - 2000) and validated using observed data (2001, 2003) at Gyeongan gauge station. The simulation results showed that runoff volume and peak rate increased as $15.0\;km^2$ forest areas decreased and $19.3\;km^2$ urban areas increased for 20 years land use changes. The runoff volume showed a higher rate of increase in wet year (2003, 1709.4 mm) than in dry year (2001, 871.2 mm). The peak runoff increased $13.3\;\%$ in normal year (2000, 1257.3 mm) because the year has the highest rain intensity (241.3 mm/hr) among the test years. The runoff volume of a dry season and a wet season (May - September) in normal year 2000 increased $4.4\;\%$ and decreased $8.1\;\%$, respectively.

Vegetation Height and Age Estimation using Shuttle Radar Topography Mission and National Elevation Datasets (SRTM과 NED를 활8한 산림수고추정 및 수령 추정)

  • Kim Jin-Woo;Heo Joon;Sohn Hong-Gyoo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.305-309
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    • 2006
  • SAR (Synthetic Aperture Radar) technology, which is not influenced by cloud cover because of using electromagnetic wave of long wavelength, has an advantage in mapping the earth. NASA, recognizing these strong points of SAR, launched SRTM (Shuttle Radar Topography klission), and acquired the topographic information of the earth. SRTM and NED (National Elevation Data) of USGS were used for the research and vegetation height map was produced through differentiating the two data. Correlation between SRTM-NED and planting year was analyzed to see the relationship. Strong correlation was detected and it shows the feasibility of estimating timber age and eventually creating timber age map from SRTM-NED. Additional analyses were conducted to check if the linearity is influenced by regional characteristics and forest uniformity. As results, the correlation between SRTM-NED and timber age is influenced by roughness of the terrain. Overall, this paper shows that timber age estimation using SRTM and NED can be sufficiently practical.

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The Comparison of Visual Interpretation & Digital Classification of SPOT Satellite Image

  • Lee, Kyoo-Seock;Lee, In-Soo;Jeon, Seong-Woo
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.433-438
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    • 1999
  • The land use type of Korea is high-density. So, the image classification using coarse resolution satellite image may not provide land cover classification results as good as expected. The purpose of this paper is to compare the result of visual interpretation with that of digital image classification of 20 m resolution SPOT satellite image at Kwangju-eup, Kyunggi-do, Korea. Classes are forest, cultivated field, pasture, water and residential area, which are clearly discriminated in visual interpretation. Maximum likelihood classifier was used for digital image classification. Accuracy assessment was done by comparing each classification result with ground truth data obtained from field checking. The classification result from the visual interpretation presented an total accuracy 9.23 percent higher than that of the digital image classification. This proves the importance of visual interpretation for the area with high density land use like the study site in Korea.

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Vegetation changes and their causes in andong dam areas (安東댐 建設에 의한 植生變化와 그 要因)

  • Song, Jong--Suk
    • The Korean Journal of Ecology
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    • v.15 no.4
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    • pp.411-431
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    • 1992
  • The present study was undertaken to classify and describe the vegetation around andong dam area, kyong-buk, korea$(36^{\circ}\;35^{\prime}\;N, \;128^{\circ}\;47^{\prime}\;E)$ by methods of the ZM school of phytosociology. The investigations were carried out in the plot. The homogeneous part of forest and grass communities was analyzed by recording the combined scale of cover-abundance and sociability of all species found in the plot. The community data obtained were classified into two associations and seven communities; festuco onvinae-pinetum densiflorae assoc. nov., quercetum variabili-serratae, quercus acutissima community, larix leptolepis, populus tomentiglandulosa, acer canadensis, prunus spp. afforestations, robinia pseudo-acacia-commelina communis community and acer palmatum cv. afforestation. The grass vegetation was divided into six associations and seventeen communities; lactuco indicae- humuletum japonicae, eragrostio ferruginei-plantaginetum asiaticae, polygonetum thunbergii, phragmitetum japonicae, eragrostio ferruginei-plantaginetum asiaticae, polygonetum thunbergii, phragmitetum japonicae, artemisio-potentilletum chinesis, eleusinetum indicae, amorpha freticosa, artemisia princeps, achyranthes fauriei and other fourteen communities. amoung the above vegetationship of the vegetation units with their environments was outlined.

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ASSESSMENT OF SPRING DROUGHT USING MODIS VEGETATION INDEX AND LAND SURFACE WATER INDEX

  • Park, Jung-Sool;Kim, Kyung-Tak;Lee, Kyo-Sung
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.563-566
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    • 2006
  • In order for the evaluation and analysis of the spring drought which has been periodically occurring in Korean peninsula since 2000, the use of satellite image data is increasing to investigate temporal and spatial characteristics of the drought areas. The recent spring droughts in south Korea have some characteristics. It last for short period in spring when the activity of vegetation is not lively and it have large areal deviation in the severity of drought. In this study, considering the characteristics of the spring drought in Korean peninsular, the MODIS satellite image data which has superior spatial and radiometric resolutions was used for the analysis of the spring drought. In two basins having different spatial characteristics, the drought events were selected and their severities were analyzed using the MODIS NDVI, LSWI, and daily rainfall data since 2000, and the spatial characteristics of the drought area were analyzed using the DEM, land cover, and digital forest map of the study areas.

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A Statistical Analysis of Tree-Harvesting Worker Safety

  • Young, Timothy M.;Guess, Frank M.
    • International Journal of Reliability and Applications
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    • v.3 no.2
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    • pp.61-80
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    • 2002
  • Tree-harvesting worker data of 508 separate worker accidents are analyzed and an exploratory approach taken. The worker accident data cover a sample of five years. The scope of the study was the southeastern United States of America. As might be hypothesized, the chainsaw was the most hazardous type of tree-harvesting equipment. It accounted for 55% of the tree-harvesting accidents. Most chainsaw accidents resulted in injuries to the lower extremities and were more frequent among younger employees. The probability of one or more chainsaw accidents occurring in any 30-day period was approximately 0.856. Chainsaw accidents were more likely to occur in late morning and early afternoon. We used statistical tools such as Pareto charts, c-charts and Ishikawa diagrams. Such tools are useful in diagnosing the root-cause of tree-harvesting worker accidents and help in developing preventive safety programs. Recommendations to help improve the quality of information of accident data collected by insurance companies and others are briefly given. The strategy and culture of continuous process improvements are stressed.

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