• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.15-25
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• 2015

The growth of impermeable layers in the city center due to today's urban development is emerging as a major cause of urban heat island effects as well as recurring inland flood damages. In order to cope with such disasters caused by climatic changes, an artificial ground afforestation system is suggested as a fundamental solution that addresses both water environment and heat environment. For the afforestation system to replace the current disaster prevention facilities, quantitative performance verification through related numerical analysis models and actual survey monitoring is necessary. Therefore, this study seeks to propose the performance predication method for the heat environment of the afforestation system by looking into correlations between measurements by physical vegetation indicators such as LAI and FVC and forecasts from FASST, a vegetation canopy model used by US Corps of Engineers.

• ALGAE
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• v.23 no.1
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• pp.83-90
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• 2008

Eelgrass beds are very productive and provide nursery functions for a variety of fish and shellfish species. Management for the conservation of eelgrass beds along the Korean coasts is critical, and requires comprehensive strategies such as vegetation mapping. We suggest a mapping method to spatial distribution and quantify of eelgrass beds using a digital echosounder. Echosounding data were collected from the northeast part of Kwangyang Bay, on the south of Korea, in March, 2007. A transducer was attached to a boat equipped with a DGPS. The boat completed a transect survey scanning whole eelgrass beds of 11.7 km2 with a speed of 1.5-2 m s-1 (3-4 knot). The acoustic reflectivity of eelgrass allowed for detection and explicit measurements of canopy cover and height. The results showed that eelgrass bed was distributed in depth from 1.19 to 3.6 m (below MSL) and total dry weight biomass of 4.1 ton with a vegetation area of 4.05 km2. This technique was found to be an effective way to undertake the patch size and biomass of eelgrass over large areas as nondestructive sampling.

• Korean Journal of Environment and Ecology
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• v.18 no.3
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• pp.279-287
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• 2004

To investigate the vegetation structure of the section of Nakdong-jeongmaek from Gajisan to Neungdongsan, fifty plots of 100$m^2$ at ten locations were set up. In accordance with the requirements of DCA(detrended correspondance analysis), which is an ordination technique, the sites were chosen contiguously with each other. The vegetation structure analysis showed Quercus dentata, Pinus densiflora, Q. mongolica to be the major species at canopy layer, Rhododendron schlippenbachii at the layer below the canopy and Tripterygium regelii at the shrub level. Shannon's diversity index was 1.5315～2.4005 per unit area of 500$m^2$. It appeared that the Quercus dentata forest of this ridge section of Nakdong-jeongmaek is about 30 or 40 years old.

• Journal of electromagnetic engineering and science
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• v.5 no.4
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• pp.183-188
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• 2005

A simple microwave backscattering model for vegetation canopies on earth surfaces is developed in this study. A natural earth surface is modeled as a two-layer structure comprising a vegetation layer and a ground layer. This scattering model includes various scattering mechanisms up to the first-order multiple scattering( double-bounce scattering). Radar backscatter from ground surface has been modeled by the polarimetric semi-empirical model (PSEM), while the backscatter from the vegetation layer modeled by the vector radiative transfer model. The vegetation layer is modeled by random distribution of mixed scattering particles, such as leaves, branches and trunks. The number of input parameters has been minimized to simplify the scattering model. The computation results are compared with the experimental measurements, which were obtained by ground-based scatterometers and NASA/JPL air-borne synthetic aperture radar(SAR) system. It was found that the scattering model agrees well with the experimental data, even though the model used only ten input parameters.

• Korean Journal of Environment and Ecology
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• v.14 no.2
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• pp.103-110
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• 2000

This study was conducted to investigate the effect of trails on breeding bird community by territory mapping method from April to August 1999 in Chirisan National Park. Twenty-five bird species were observed and 18 bird species bred in 4 study sites. Thirteen species bred in Imgullyung site 14 species in Imgullyung trail site 14 species in the Nogodan site and 15 species in the Nogodan trail site. There were bred 62.0 pairs of birds in the Imgullyung site 55.0 pairs in the Imgullyung trail site 36.5 pairs in the Nogodan site and 36.5 pairs in the Nogodan trail site in the breeding season 1999. There were no differences in breeding bird communities among 4 sites. The nesting and foraging guild structures were similar among 4 sites. It seems that trails do not influences on the breeding bird community becasuse the canopy layer was similair and connected and understory vegetation was developed around the trails. It would be needed the maintenance and management of canopy layer and understory vegetation for the protection and management of bird communities around the trails.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.1-8
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• 2003

This study was conducted to investigate the effects of road on bird community by line transect census method from May 2000 to January 2001 in Mt. Geumsan, Namhae-Gun, Kyeongsangnam-do. Canopy layer was more developed in forest area than road area. Understory vegetation of road area was more developed than forest area. Twenty six and twenty three bird species were observed in road and forest area, respectively, White's thrush and ashy minivet were observed just only in forest area, and Siberian blue robin, blue-and-white flycatcher and gold crest were in road area. The birds being to bush nesting and foraging guilds in road area were more than forest area. It is known that the road construction was negatively affected on bird community. However, road construction would be not so negative on bird community according to the results of thie study. It would be needed the maintenance of upper canopy layer and understory vegetation to reduce negative effect of road on bird communities in forest area.

• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.77-83
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• 2015

Leaf water content is one of important indicators that shows states of vegetation. It is important to monitor vegetation water content using remote sensing for forest management. In this study, we investigated the degree of water stress in Korean peninsula with Normalized Difference Water Index (NDWI) to study the water content of vegetation canopy. We calculated the NDWI using SPOT/VEGETATION S10 channel data over forest from 1999 to 2013. We calculated Simple Moving Average (SMA) to remove temporal noises of NDWI in time series, and used standardized anomaly to investigate temporal changes. We classified the NDWI anomalies into three scales (low, moderate, and high) in order to monitor intuitively. We also investigated suitability of the NDWI as an evaluation criterion about water stress of vegetation canopy by comparing and verifying forest fires damaged area over 150 ha. Consequently, huge forest fire occurred 24 times during the study period. Also, negative anomalies appeared in every forest fire location and their neighboring areas. In particular, we found huge forest fires where NDWI anomalies were in 'high' scale.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.2
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• pp.173-181
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• 1997

To estimate the leaf area index(LAI) of rice plant by non-destructive method, spectral reflectance from rice plant canopy was measured by using the spectroradiometer (LI-1800, LICOR Inc.) with one week interval during the rice growing season at Suwon paddy field in 1993. LAI of two medium late maturing varieties, Daechungbyeo and Ilpumbyeo, and one early maturing variety, Jinbubyeo, were observed and compared with those estimated by vegetation index. The reflectance(R) of visible wavelength remained less than 0.1 over entire growing season, but that of near infrared wavelength remained from 0.1 to 0.5 with the significant positive correlation with LAI. Vegetation index determined by the reflectance of visible against near infrared wavelength showed high correlation with LAI of rice canopy. Vegetation index derived from wide band ratio, NIR(720~1, 100nm) /Blue(400~500nm), showed the highest correlation coefficient with LAI. Vegetation index derived from narrow band(10nm interval) ratio, R910/R460, from transplanting to heading stage corresponded well to measured values (Y=0.16799X-0.79776 ; $R^2$=0.94). But another vegetation index, NIR(720~1, 100nm) /Red (600~700nm), showed higher correlation with LAI than NIR /Blue did from heading stage to maturity.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.158-174
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• 2018

The leaf area index (LAI) is a major factor explaining the photosynthesis of vegetation, evapotranspiration, and energy exchange between the earth surface and atmosphere, and there have been studies on accurate and applicable LAI estimation methods. This study aimed to investigate the relationship between the actual LAI data, UAV image-based vegetation index, canopy height and satellite image (Sentinel-2) LAI and to present an effective LAI estimation method using UAV. As a result, among the six vegetation indices in this study, NDRE ($R^2=0.496$) and CIRE ($R^2=0.443$), which contained red-edge band, showed a high correlation. The application of the canopy height model data to the vegetation index improved the explanatory power of the LAI. In addition, in the case of NDVI, the saturation problem caused by the linear relationship with LAI was addressed. In this study, it was possible to estimate high resolution LAI using UAV images. It is expected that the applicability of such data will be improved if calibration and correction steps are carried out for various vegetation and seasonal images.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.305-311
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• 2006

Although there have been several attempts to estimate forest LAI using optical remote sensor data, there are still not enough evidences whether the NDVI is effective to estimate forest LAI, particularly in fully closed canopy situation. In this study, we have conducted a simple correlation analysis between LAI and spectral reflectance at two different settings: 1) laboratory spectral measurements on the multiple-layers of leaf samples and 2) Landsat ETM+ reflectance in the close canopy forest stands with fieldmeasured LAI. In both cases, the correlation coefficients between LAI and spectral reflectance were higher in short-wave infrared (SWIR) and visible wavelength regions. Although the near-IR reflectance showed positive correlations with LAI, the correlations strength is weaker than in SWIR and visible region. The higher correlations were found with the spectral reflectance data measured on the simulated vegetation samples than with the ETM+ reflectance on the actual forests. In addition, there was no significant correlation between the forest.LAI and NDVI, in particular when the LAI values were larger than three. The SWIR reflectance may be important factor to improve the potential of optical remote sensor data to estimate forest LAI in close canopy situation.