• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.365-369
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• 2006

This study was conducted to clarity the differences in density and body weight of rodents among unburned and two burned areas (silvicultured and natural restored areas) after forest fire from July to September 2004 in coniferous forest of Samcheok, Korea. The density of rodents was the least in the silvicultured area. There was no differences in density between the unburned and natural restored areas. Also, mean body weight of rodents in the natural restored area was higher than in the silvicultured area. Shrubs, seedlings, snags and CWD (coarse woody debris) would be good for inhabitation of the rodents in forest fired area. Therefore, coverage of understory layer should be maintained in forest fired area.

• Fire Science and Engineering
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• v.19 no.4 s.60
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• pp.75-79
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• 2005

This study has developed Forest Fire Occurrence Danger Index (FFODI) using fuel and topographical characteristics for the practical purposes of forecasting forest fire occurrence danger rating. This was made on the basis of the 126 forest fire site according to field survey. The result of fire frequency analysis showed 87 sites on conifer $(69\%)$, 21 on mixed $(16.7\%)$ and 18 $(14.3\%)$ on non-conifer. The scale for Fuel Model Index(FMI) ranges from 1 to 10 and Topography Model Index(TMI) from 1 to 5. FMI is 10 on the conifer, 3 on the mixed and 2 on the non-conifer. In case of topographical analysis, it was estimated that 90 site $(71.4\%)$ of ignition point was bottom foot hill and 22 site $(17.5\%)$ was on the southwest. TMI in southwest direction is 5.0, 4.5 in the northwest and the northeast, 4.0 in the southeast and the south, 2.5 in the north and the west and 1.5 in the east. TMI in the bottom foot hill is 5 in the bottom foot hill, 1.5 in the upper foot hill, 1.0 in the bottom middle slope and 0.5 in the upper middle slope and bottom ridge.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.1
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• pp.17-25
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• 2013

In this paper we interpreted the changes in wind field over complex mountainous terrains. The results of our study can be applied for predicting the direction of fire spread and for establishing strategies for fire prevention. The study area is bounded by $12{\times}12$ km domains of the Samcheok's long-term ecological research (LTER) site located in the east coast, in which a large-fire had occurred from 7 to 13 April 2000. Because of the area's complex topography, we compared the result of the Weather Research and Forecasting (WRF) mesoscale model with those observed by four automated weather stations. The WRF simulation overestimated the wind speed by 5 to 8 m/s (~200%) in comparison with those from four automated weather stations. The wind directions observed by the AWSs were from various directions whereas those from WRF model were mostly west wind at all stations. Overall, the simulations by the WRF mesoscale models were not appropriate for the estimation of microscale wind fields over complex mountainous areas. To overcome such inadequacy of reproducing the wind fields, we employed the ENVI-met model over Samcheok's LTER site. In order to test the model's sensitivity with the terrain effects, experimental simulations were conducted with various initial conditions. The simulation results of the ENVI-met model showed a reasonable agreement in wind speeds (about 70% accuracy) with those of the four AWSs. Also, that the variations in wind directions agreed reasonably well with changes in terrain effect. We concluded that the ENVI-met model is more appropriate in representing the microscale wind field over complex mountain terrains, which is required to predict fire spread and to establish strategies for forest fire prevention.

• Korean Journal of Remote Sensing
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• v.35 no.2
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• pp.343-346
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• 2019

This letter describes a development of satellite-based forest withering index for detection of fire burn area and its application to the Goseong-Sokcho and Gangneung-Donghae wildfires in April 4, 2019. Withered forest has very different spectral characteristics from healthy forest. In particular, a false color composite of R-NIR-G represents such difference very clearly. Using Sentinel-2 images with the forest withering index, we derived the area burned by the wildfires: approximately 701.16 ha for Goseong-Sokcho and approximately 710.60 ha for Gangneung-Donghae, although official record will be announced by the Korean government later.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.334-341
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• 2006

This study was to investigate the growth of planted red pine (Pinus densiflora S. et. Z.) seedling, soil properties and understory vegetation structure after fertilizer treatments [unfertilized plot (control), CF plot (Combination Fertilizer), UF plot (Urea Formaldehyde Fertilizer)] in a Pinus densiflora stand planted after the forest fires in Gosung, Gangwon province. The height growth rates of seedlings in four years were 264% in unfertilized, 404% in CF, and 388% in UF plots, respectively. The root collar diameters were increased 340% in unfertilized, 454% in CF, and 427% in UF plots, respectively. No significant changes occurred in soil total nitrogen and potassium ion ($K^+$) with the fertilization. However, available $P_2O_5$, content in the soil surface (0-15 cm) increased with the fertilizer application. Soil organic matter increased significantly with fertilizer treatments, while gradual decrease occurred in unfertilized plots. Sodium ion ($Na^-$) decreased in all sites. Soil pH, CEC, calcium ion ($Ca^{2+}$) and magnesium ion ($Mg^{2+}$) contents were not significantly different among treatments. Although Shannon's species diversity index and species richness in understory vegetation did not change with fertilizer treatments, vegetation cover rates in forest floor increased significantly with the fertilization. These results suggest that the increase of pine seedling growth and vegetation cover rates with fertilization could enhance soil stabilization in forest tire areas.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.4
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• pp.47-64
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• 2019

The purpose of this study is to present the basic data for the management of National Park by surveying and analysing the change of vegetation of forest fire damaged area in Sogeumgang District, Gyeongju National Park. The covergae ratio, a number of species and dominant species changed overall in forest fire damaged area. The final result of the change is as follows. In case of coverage ratio in the shrub layer, Site 1 was 30%, 40% in Site 2, 50% in Site 3, 60% in Site 4 and 30% in Site 5. In the herb layer, Site 1 was 90%, 80% in Site 2, 90% in Site 3, 60% in Site 4 and 20% in Site 5. In case of the number of species in the shrub layer, Site 1 was 11 species, 8 species in Site 2, 6 species in Site 3, 10 species in Site 4, 7 species in Site 5, and in the herb layer, Site 1 was 22 species, 25 species in Site 2, 12 species in Site 3 and Site 4 each and 11 species in Site 5. In the dominant species, the shrub layer was Lespedeza maritima(Site 1, 2), Quercus serrata(Site 3), Quercus serrata and Lespedeza bicolor(Site 4) and Styrax japonicus(Site 5), the herb layer was Miscanthus sinensis var. purpurascens(Site 1, 3), Pteridium aquilinum var. latiusculum and Carex humilis var. nana(Site 2), Quercus serrata(Site 4) and Carex humilis var. nana andS tyrax japonicus(Site 5). The number of vascular plants was summarized as 91 taxa including 35 families, 69 genera, 78 species, 2 subspecies, 10 varieties and 1 form.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.149-156
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• 2005

This study was conducted to elucidate the relationship between the aboveground vegetation structure and fine roots of the topsoil (<15m), and thereafter to obtain the regression models for the estimation of the fine roots of the topsoil using the aboveground vegetation values in the burned forest areas, Korea. The FRT (fine roots of the top soil) as well as the aboveground vegetation structure showed spatial variation in the earlier successional stages after forest fire. The fine roots (<2 mm) of the topsoil in the earlier successional stages than the first 3 year after forest fire showed the range from 3 to 166 g $DM/m^2$. The FRT in the naturally regenerated sites and planted sites after forest fire was closely correlated with the vegetation indices, especially lvc, representing the development status of the aboveground vegetation. The FRT in the terrace seeding work sites after forest fire was closely correlated with year elapsed after terrace seeding work. The FRT in the terrace seeding work sites showed the much higher values because of the vigorous growth of grass species than the other sites. In the naturally regenerated sites, the FRT showed the parabola form according to the increment of aboveground vegetation value (Ivc). Although the aboveground vegetation value (Ivc) showed a tendency to increase logarithmically during the secondary succession after forest fire, the estimated fine roots of the topsoil was depicted the parabola form showing the gradual increment until the first 15 years and slight decrease thereafter. Decrease of FRT in the later successional stage showing the high vegetation value may be caused by increment of the woody species contribution to the vegetation value (Ivc). Our results represented that the aboveground vegetation value (Ivc) can be used to the estimation of the fine roots of the topsoil in burned forest areas.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1413-1425
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• 2023

The increasing frequency of wildfires due to climate change is causing extreme loss of life and property. They cause loss of vegetation and affect ecosystem changes depending on their intensity and occurrence. Ecosystem changes, in turn, affect wildfire occurrence, causing secondary damage. Thus, accurate estimation of the areas affected by wildfires is fundamental. Satellite remote sensing is used for forest fire detection because it can rapidly acquire topographic and meteorological information about the affected area after forest fires. In addition, deep learning algorithms such as convolutional neural networks (CNN) and transformer models show high performance for more accurate monitoring of fire-burnt regions. To date, the application of deep learning models has been limited, and there is a scarcity of reports providing quantitative performance evaluations for practical field utilization. Hence, this study emphasizes a comparative analysis, exploring performance enhancements achieved through both model selection and data design. This study examined deep learning models for detecting wildfire-damaged areas using Landsat 8 satellite images in California. Also, we conducted a comprehensive comparison and analysis of the detection performance of multiple models, such as U-Net and High-Resolution Network-Object Contextual Representation (HRNet-OCR). Wildfire-related spectral indices such as normalized difference vegetation index (NDVI) and normalized burn ratio (NBR) were used as input channels for the deep learning models to reflect the degree of vegetation cover and surface moisture content. As a result, the mean intersection over union (mIoU) was 0.831 for U-Net and 0.848 for HRNet-OCR, showing high segmentation performance. The inclusion of spectral indices alongside the base wavelength bands resulted in increased metric values for all combinations, affirming that the augmentation of input data with spectral indices contributes to the refinement of pixels. This study can be applied to other satellite images to build a recovery strategy for fire-burnt areas.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.36-44
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• 2010

In order to rehabilitate forest sites damaged by wildfire via natural or artificial restoration, it is important to determine right tree species, which can acclimate to biogeoclimatic environment at the sites. The objectives of this study were to develop site index equation of different tree species for estimating forest productivity and to provide information on species selection for post-wildfire restoration. Site index equation was developed based on environmental information from wildfire damaged areas in Gangneung, Goseong, Donghae, and Samcheok, where were located in east coastal areas of South Korea. Despite the small numbers (4~5) of environmental variables used for the development of the site index equations, statistical analysis (e.g. mean difference, standard deviation of difference, and standard error of difference) showed relatively low bias and variation, suggesting that those equations can provide relatively high capability of estimation and practical applicability with high effectiveness. The small numbers of the variables enabled the model to be applied in a wide range of usages including determination of appropriate tree species for post-wildfire restoration. The estimation of forest site productivity showed the possibility of large distribution in east coastal region as the best site for Korean ash (Fraxinus rhynchophylla) and original oak (Quercus variabilis) that can be used for firebreak in the region. These results imply that damages by forest fire can be reduced significantly by replacing existing pure coniferous forests in the area with ones dominated by broad-leaved deciduous stands, which can play an important role as fire break and/or prevent a transition from surface fire to crown fire.

• Journal of Forest and Environmental Science
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• v.19 no.1
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• pp.99-107
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• 2003

For the investigation of the potentials of ectomycorrhizal (ECM) fungi on pine seedlings for reforestation on fire-damaged forest lands, six months old seedlings of Pinus densiflora, which were artificially inoculated or non-inoculated with Pisolithus tinctorius, were transplanted into the fire-damaged forest land. Seedling mortality was recorded as 3.5% for the seedlings inoculated with P. tinctorius at three months after transplanting, while it was 70.5% for the non-inoculated seedlings. Mycorrhizal root formation was shown as typically Y-branched type, and thier rate was 82% for inoculated seedlings, but it was 52% for non-inoculated. Comaprisons in seedling height, fresh weight, and dry weight between pine seedlings inoculated or non-inoculated with P. tinctorius at every 3 months till 9 months after transplanting showed that the inoculated seedlings were much better in all criteria as compared to the non-inoculated at the level of 63%, 35%, 18% in seedling height, 206%, 114%, 70% in fresh weight, and 187%, 109%, 63% in dry weight, respectively. The percentages were decreased by the elapse of time, which indicate that P. tinctorius give a growth-stimulating effects on seedlings at the early stage. T/R ratio for inoculated and non-inoculated seedlings after 9 months was 1.75 and 1.90, respectively.