• Title/Summary/Keyword: Vegetation studies

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Analyses and trends of forest biomass in higher Northern Latitudes

  • Tsolmon, R.;Tateishi, R.;Sambuu, B.;Tsogtbayar, Sh.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.965-967
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    • 2003
  • Information on forest volume, forest coverage and biomass are important for developing global perspectives about CO$_{2}$ concentration changes. Forest biomass cannot be directly measured from space yet, but remotely sensed greenness can be used to estimate biomass on decadal and longer time scales in regions of distinct seasonality, as in the north. Hence, in this research, numerical methods were used to estimate forest biomass in higher northern regions. A regression model linking Normalized Difference Vegetation Index(NDVI), to forest biomass extracted from SPOT/4 VEGETATION data and PAL 8km data in regional and continental area (N40-N70) respectively. Statistical tests indicated that the regression model can be used to represent the changes of forest biomass carbon pools and sinks at high latitude regions over years 1982-2000. This study suggests that the implementation of estimation of biomass based on 8-km resolution NOAA/AVHRR PAL and SPOT-4/VEGETATION data could be detected over a range of land cover change processes of interest for global biomass change studies.

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Linear Spectral Mixture Analysis of Landsat Imagery for Wetland land-Cover Classification in Paldang Reservoir and Vicinity

  • Kim, Sang-Wook;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
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    • v.20 no.3
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    • pp.197-205
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    • 2004
  • Wetlands are lands with a mixture of water, herbaceous or woody vegetation and wet soil. And linear spectral mixture analysis (LSMA) is one of the most often used methods in handling the spectral mixture problem. This study aims to test LSMA is an enhanced routine for classification of wetland land-covers in Paldang reservoir and vicinity (paldang Reservoir) using Landsat TM and ETM+ imagery. In the LSMA process, reference endmembers were driven from scatter-plots of Landsat bands 3, 4 and 5, and a series of endmember models were developed based on green vegetation (GV), soil and water endmembers which are the main indicators of wetlands. To consider phenological characteristics of Paldang Reservoir, a soil endmember was subdivided into bright and dark soil endmembers in spring and a green vegetation (GV) endmember was subdivided into GV tree and GV herbaceous endmembers in fall. We found that LSMA fractions improved the classification accuracy of the wetland land-cover. Four endmember models provided better GV and soil discrimination and the root mean squared (RMS) errors were 0.011 and 0.0039, in spring and fall respectively. Phenologically, a fall image is more appropriate to classify wetland land-cover than spring's. The classification result using 4 endmember fractions of a fall image reached 85.2 and 74.2 percent of the producer's and user's accuracy respectively. This study shows that this routine will be an useful tool for identifying and monitoring the status of wetlands in Paldang Reservoir.

Study on Particulate Pollutant Reduction Characteristics of Vegetation Biofilters in Underground Subway Stations (지하역사내 식생바이오필터의 입자상 오염물질 저감특성 연구)

  • Kim, Tae Han;Oh, Ji Eun;Kim, Mi Ju
    • Journal of the Semiconductor & Display Technology
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    • v.21 no.4
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    • pp.99-105
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    • 2022
  • Public attention to the indoor environment of underground subway stations, which is a representative multi-use facility, has been increasing along with the increase in indoor activities. In underground stations, fine iron oxide, which affects the health of users, is generated because of the friction between wheels and rails. Among particulate pollutant reduction technologies, plants have been considered as a non-chemical air purification method, and their effects in reducing certain chemical species have been identified in previous studies. The present study aimed to derive the total quantitative and qualitative reduction effects of a bio-filter system comprising air purifying plants, installed in an underground subway station. The experiment proceeded in two ways. First, PM(particulate matter) reduction effect by vegetation biofilter was monitored with the IAQ(indoor air quality) station. In addition, chemical speciation analysis conducted on the samples collected from the experimental and control areas where plants and irrigation using SEM-EDS(scanning electron microscopy-energy dispersive X-ray spectroscopy). This study confirmed the effect of the vegetation bio-filter system in reducing the accumulation of particulate pollutants and transition and other metals that are harmful to the human body.

Estimation of Vegetation Carbon Budget in South Korea using Ecosystem Model and Spatio-temporal Environmental Information (생태계 모형과 시공간 환경정보를 이용한 우리나라 식생 탄소 수지 추정)

  • Yoo, Seong-Jin;Lee, Woo-Kyun;Son, Yo-Whan;Ito, Akihiko
    • Korean Journal of Remote Sensing
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    • v.28 no.1
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    • pp.145-157
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    • 2012
  • In this study, we simulated a carbon flux model, so called Vegetation Integrated Simulator for Trace gases (VISIT) using Spatio-temporal Environmental Information, to estimate carbon budgets of vegetation ecosystem in South Korea. As results of the simulation, the model estimated that the annual-average gross primary production (GPP), net primary production (NPP) for 10 years were $91.89Tg\;C\;year^{-1}$, and $40.16Tg\;C\;year^{-1}$, respectively. The model also estimated the vegetation ecosystems in South Korea as a net carbon sink, with a value of $3.51Tg\;C\;year^{-1}$ during the simulation period. Comparing with the anthropogenic emission of South Korea, vegetation ecosystems offsets 3.3% of human emissions as a net carbon sink in 2007. To estimate the carbon budget more accurately, it is important to prepare reliable input datasets. And also, model parameters should be calibrated through comparing with various independent method. The result of this study, however, would be helpful for devising ecosystem management strategies that may help to mitigate global climate change.

Environmental Friendliness Assessment of Golf Courses in the Capital Region of Korea (수도권 지역 골프장의 환경친화성 평가)

  • 김광두;방광자;강현경
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.5
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    • pp.20-30
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    • 2003
  • This study is aimed at establishing the categories and items for ecological assessment and evaluation of the environmental friendliness of golf courses in the capital region of Korea. The categories and items for the assessment have been derived based on the existing literature and interviews with golf experts. This study covers 32 golf courses in the capital region of Korea that are available in terms of data and on-site surveys. In order to conduct a comprehensive assessment of the environmental friendliness of the golf courses, the assessment area was divided into 4 categories that include a total of 14 sub-categories. The 4 categories encompass 1) location, 2) topography, 3) vegetation, and 4) construction. As its sub-categories, the location category includes current land use and zoning in the National Land Use Management Law. Topography has 2 sub-categories in the damage ratio of existing topography, gradient, cut area, and slope height. The assessment of vegetation is largely based on site surveys in the categories of preservation of the existing vegetation, the use of natural resources and existing trees, the component ratio of native tree species, the multi-layered structure of vegetation, and the utilization of water purification plants. In the aspect of construction, afforestation on tile slopes and the utilization of existing surface soil were evaluated. The examination of comparative analysis among the 10 items as a ratio measure showed that the scores were low in the sub-categories of current land we, the use of existing trees, and the multi-layered structure of vegetation. However, the rating results were satisfactory in the 2 sub-categories including cut area, and the utilization of native tree species. Those proved to be contributing factors in the ecological health of the golf courses. According to correlation analysis of the 10 items to the overall ecological rating of each golf course, the sizes of the 32 golf courses were mainly affected by the damage ratio of existing topography, gradient, preservation of vegetation and slope height. This study has the initiative to conduct an ecological assessment of golf courses in the country based on site surveys. The study results revealed that location factors such as current land use, damage ratio of topography and gradient and topographical factors were the main factors affecting the environmental friendliness of golf courses. This indicates indicating the significance of these factors in the future construction practices of golf courses. Furthermore, this study raises the need for follow-up studies to establish more detailed assessment criteria and to develop assessment techniques for areas such as slope afforestation and water purification plants that need a qualitative approach.

A Study of Spring Drought Using Terra MODIS Satellite Image - For the Soyanggang Dam Watershed - (Terra MODIS 위성영상을 이용한 봄 가뭄 연구 - 소양강댐유역을 대상으로 -)

  • SHIN, Hyung-Jin;PARK, Min-Ji;HWANG, Eui-Ho;CHAE, Hyo-Sok;PARK, Seong-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.4
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    • pp.145-157
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    • 2015
  • In 2015, drought was at the worst stage of devastation in Soyanggang Dam watershed. The purpose of this study is to trace the drought area around Soyanggang dam watershed by using Terra MODIS image because it has the ability of spatio-temporal dynamics. The MODIS indices, which included the enhanced vegetation index (NDVI), were extracted from MODIS product MOD13 16-day composite datasets with a spatial resolution of 250m from 2010.01.01 to 2015.06.30. We found that application of Vegetation Condition Index (VCI) and Standardized Vegetation Index (SVI) was suitable for monitoring the drought area. The result can be used to acquire the drought data scattered and demonstrate the potential for the use of MODIS data for temporal and spatial detection of drought effects.

The Possibility of Drought Expression by Late March Dryness in Rice Paddy Areas Using Terra MODIS NDVI (Terra MODIS NDVI를 활용한 3월말 논지역 건조상태에 따른 가뭄표현 가능성 연구)

  • LEE, Ji-Wan;LEE, Yong-Gwan;KIM, Seong-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.20 no.3
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    • pp.27-41
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    • 2017
  • The purpose of this study is to diagnose the possibility of future drought expression by late March dryness in rice paddy areas using Terra MODIS NDVI (Normalized Difference Vegetation Index). We tested the degree of dryness by comparing the 2000-2015 average NDVI with yearly NDVI, which we name DCI (Dry Condition Index). The 16-day interval DCIs from March 6 to May 25 were evaluated with spatio-temporal expression of South Korea. In particular, we find that the DCI for April 7 (March 23 to April 7) offered reasonable prediction of paddy dryness during drought years. The April 7 DCI value for dry conditions ranged from 0.04 to 0.08 while the DCI for normal conditions ranged from -0.04 to 0.01. The DCI can be one of the indicators used to evaluate the dryness of rice paddy areas at the beginning of the spring season.

Estimation of the Available Green Roof Area using Geo-Spatial Data (공간정보를 이용한 옥상녹화 가용면적 추정)

  • Ahn, Ji-Yeon;Jung, Tae-Woong;Koo, Jee-hee
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.5
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    • pp.11-17
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    • 2016
  • The purposes of this research are to estimate area of greenable roof and to monitor maintaining of green roofs using World-View 2 images. The contents of this research are development of World-View 2 application technologies for estimation of green roof area and development of monitoring and maintaining of green roofs using World-View 2 images. The available green roof areas in Gwangjin-gu Seoul, a case for this study, were estimated using digital maps and World-View 2 images. The available green roof area is approximately 12.17% ($2,153,700m^2$) of the total area, and the roof vegetation accounts for 0.46% ($80,660m^2$) of the total area. For verification of the extracted roof vegetation, Vworld 3D Desktop map service was applied. The study results may be used as a decision-making tool by the government and local governments in determining the feasibility of green roof projects. In addition, the project implementer may periodically monitor to see whether roof greening has maintained for efficient management of projects, and a vast amount of World-View 2 images may be regularly used before and after the projects to contribute to sharing of satellite images information.

Studies on the Distribution and Vegetation of Ambrosia artemisiifolia var, elatior Community Group in Jeju Island (제주도 돼지풀군락군의 분포와 식생에 관한 연구)

  • 양영환;김문홍
    • Korean Journal of Plant Resources
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    • v.16 no.1
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    • pp.15-24
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    • 2003
  • The study was performed to understand the actual vegetation by using the phytosociological method on the Ambrosia artemisiifolia var. elatior community group in Jeju Island. The flora was composed of 48 families, 156 genera, 200 species, 28 varieties, 2 forma or 230 taxa. The Ambrosia artemisiifolia var. elatior community group vegetation was classified into two communities and one association; Erigeron annuus - Conyza sumatrensis, Bromus tectorum - Bidens pilosa, Setaria viridis - Eleusine indica community and Lactuco indicae - Humuletum japonicae association. Ambrosia artemisiifolia var. elatior community group was wide from the coastal areas up to the elevation of 1500 meter on Young sil of Mt. Halla. The highest dominance of the Ambrosia artemisiifolia var. elatior is 345 meter which is located near Seoneheul-ri Jocheon-eup, on the other hand the lowest one is located 1020 meter near Young-sil of Mt. Halla.