• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.1-10
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• 2011

This program was developed to operate and manage the massive digital forest cover type map using SDE(spatial database engine) in order to solve the problems of the analogue mapping system, mapping process and managing vast amounts of data. It was established the standardization process by performing the several functions of application related to the spatial DB search, mapping history and progress control, modification and inspection of the topology error, approval and reject of those maps. It can be possible to generate the effective mapping and distribute maps to the public service. It is expected that the results will be able to reduce time-cost.

• Journal of Climate Change Research
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• v.8 no.4
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• pp.329-337
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• 2017

In this study, land-use changes from 1990 to 2010 in Jeju Island by different approaches were produced and compared to suggest a more efficient approach. In a sample-based method, land-use changes were analyzed with different sampling intensities of 2 km and 4 km grids, which were distributed by the fifth National Forest Inventory (NFI5), and their uncertainty was assessed. When comparing the uncertainty for different sampling intensities, the one with the grid of 2 km provided more precise information; ranged from 6.6 to 31.3% of the relative standard error for remaining land-use categories for 20 years. On the other hand, land-cover maps by a wall-to-wall approach were produced by using time-series Landsat imageries. Forest land increased from 34,194 ha to 44,154 ha for 20 years, where about 69% of total forest land were remained as forest land and 19% and 8% within forest lands were converted to grassland and cropland, respectively. In the case of grassland, only about 40% of which were remained as grassland and most of the area were converted to forest land and cropland. When comparing land-cover area by land-use categories with land-use statistics, forest areas were underestimated while areas of cropland and grassland were overestimated. In order to analyze land use change, it is necessary to establish a clear and consistent definition on the six land use classification.

• Journal of Forest and Environmental Science
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• v.35 no.1
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• pp.6-24
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• 2019

We have investigated the impact of anthropogenic and natural disturbances on regeneration, composition and diversity in some temperate forests of Bhagirathi Catchment Area of Garhwal Himalaya. The forests were categorized on the basis of canopy cover and magnitude of disturbance into highly, moderately and least disturbed classes. The dominant tree species at lower elevation were Pinus roxburghii and Quercus leucotrichophora, while Abies pindrow, Q. semecarpifolia and Rhododenron arboreum were the dominant species at the upper elevational forests. Cythula tomentosa and Indegophera heterentha were the dominant shrub species present in all the forests. Similarly, Circium wallichii and Oxalis corniculata were the dominant herb species found in all forests (except Q. leucotrichophora forest), whereas Thalictrum foliolosum and Viola pilosa were noticed in each forest (except P. roxburghii forest). The tree density values oscillated between $400{\pm}10\;trees\;ha^{-1}$ to $750{\pm}89.1\;trees\;ha^{-1}$ which generally decreased from lower to higher disturbance regimes however, the total basal cover value was highest ($88.1{\pm}23.6m^2\;ha^{-1}$) in highly disturbed forest and lowest ($25.8{\pm}2.2m^2\;ha^{-1}$) in moderately disturbed forest. The shrub and herb densities were maximum in least disturbed forest, while the young regenerating individuals i.e., sapling and seedling were observed increasing from high to low disturbed forests which reflected that the forest fragmentation adversely affected the regeneration. However, A. pindrow and P. roxburghii were found invariably encroaching the habitats of R. arboreum and Q. leucotrichophora at various altitudes, respectively. The Canonical Correspondence Analysis clearly indicated that the elevation and lopping intensity have more impact on trees, while shrub and herbs were more influenced by elevation, canopy cover, light attenuation and soil erosion. Pinus roxburghii was the only species which was affected by heavy litter removal and forest fire.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.3
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• pp.1-18
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• 2024

The study aims to establish a direction for forest ecological restoration by classifying forest types and understanding the ecological characteristics of the Uljin forest area damaged by a large fire in 2022. Hierarchical cluster analysis and indicator species analysis were conducted on 78 survey plots located in the forest fire-affected area, and four forest cover types were derived: P. densiflora pure forests, P. densiflora dominant forests, mixed broad-leaved forests, and Q. variabilis dominant forests. As a result of visually comparing changes in forest types before and after forest fire damage, by classifying data according to whether or not upper dead trees are included, it was confirmed that pine forests, which have a high proportion of pine trees, spread widely due to forest fire damage. However, broad-leaved mixed forests and oyster oak dominant forests showed characteristics of maintaining concentration, indicating that pine forests were severely damaged. As a result of the important value analysis, during the process of natural recovery after a forest fire, the species that appear early in the lower layer are the sprouts of existing species such as Quercus mongolica Fisch. ex Ledeb., Quercus variabilis Blume, Fraxinus sieboldiana Blume, Rhododendron mucronulatum Turcz. The distribution of diameter at breast height by forest cover type showed that among areas with extreme forest fire damage, the proportion of dead trees was relatively high and structural changes were large in P. densiflora pure forests and P. densiflora dominant forests where pine trees had a high distribution ratio. However, if continuous monitoring is carried out in the future with reference to the results of this study and plant data is collected and analyzed from a mid- to long-term perspective, it is believed that it will be used as useful data to promote forest ecological restoration projects in forest fire-affected areas.

• Journal of Forest and Environmental Science
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• v.33 no.4
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• pp.295-304
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• 2017

This study compared and analyzed the construction of a land use change matrix for the Intergovernmental Panel on Climate Change's (IPCC) land use, land use change, and forestry area (LULUCF). We used National Forest Inventory (NFI) permanent sample plots (with a sample intensity of 4 km) and permanent sample plots with 500 m sampling intensity. The land use change matrix was formed using the point sampling method, Level-2 Land Cover Maps, and forest aerial photographs (3rd and 4th series). The land use change matrix using the land cover map indicated that the annual change in area was the highest for forests and cropland; the cropland area decreased over time. We evaluated the uncertainty of the land use change matrix. Our results indicated that the forest land use, which had the most sampling, had the lowest uncertainty, while the grassland and wetlands had the highest uncertainty and the least sampling. The uncertainty was higher for the 4 km sampling intensity than for the 500 m sampling intensity, which indicates the importance of selecting the appropriate sample size when constructing a national land use change matrix.

• Journal of Korean Society of Forest Science
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• v.112 no.3
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• pp.267-279
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• 2023

This research assessed the feasibility of using high-resolution aerial images and deep learning algorithms for estimating the land-use and land-cover areas at the Approach 3 level, as outlined by the Intergovernmental Panel on Climate Change. The results from different sampling densities of high-resolution (51 cm) aerial images were compared with the land-cover map, provided by the Ministry of Environment, and analyzed to estimate the accuracy of the land-use and land-cover areas. Transfer learning was applied to the VGG16 architecture for the deep learning model, and sampling densities of 4 × 4 km, 2 × 4 km, 2 × 2 km, 1 × 2 km, 1 × 1 km, 500 × 500 m, and 250 × 250 m were used for estimating and evaluating the areas. The overall accuracy and kappa coefficient of the deep learning model were 91.1% and 88.8%, respectively. The F-scores, except for the pasture category, were >90% for all categories, indicating superior accuracy of the model. Chi-square tests of the sampling densities showed no significant difference in the area ratios of the land-cover map provided by the Ministry of Environment among all sampling densities except for 4 × 4 km at a significance level of p = 0.1. As the sampling density increased, the standard error and relative efficiency decreased. The relative standard error decreased to ≤15% for all land-cover categories at 1 × 1 km sampling density. These results indicated that a sampling density more detailed than 1 x 1 km is appropriate for estimating land-cover area at the local level.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.239-246
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• 2013

This study observed changes of understory vegetation to evaluate the role of forest aggregate after 15% aggregated retention harvest in mature oak forest (> 100 years) in Gyungsangbukdo Bonghwagun in 2010 and 2011. Spontaneous responses of understory vegetation cover (%), species richness, abundance of plant growth forms (herbaceous and woody plants), and overall attributes (by Ordination analysis) were estimated in aggregate area (0.15 and n=36) and clear cut area (0.85 and n=192) in experimental site and control site (1 and n=300). Based on ordination analysis, overall change of species composition in aggregated sites were relatively lower than in harvest area. Right after treatment, total cover of cutted area slightly decreased from 15.6% to 14.7%, and species richness increased from 14 species to 22 species. Cover and richness in the both of aggregate and control sites increased. In plant growth forms, 15% aggregate harvest revealed positive effects on the abundance (cover and richness) of herbaceous plants than woody group. After retention treatment, overall, edge effect likely played major component of vegetation changes in aggregate forest and in harvested area, mechanical damage from harvest operation and change of forest structure by clear cutting were critical. As pre-treatment data, which are rare in ecological studies in Korea, were critical for interpretation between patterns that may have arisen from spatial distributions in the original forest, our experimental design have higher opportunity for long term monitoring on the effect of forest aggregate and vegetation regeneration in clear cutted area.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.13-22
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• 2015

Unpaved forest roads are common accessways in mountain areas being used for forestry purposes. The presence of forest roads produces large volumes of surface runoff and sediment yield due to changes in soil properties and hillslope profile. Rainfall simulation experiments were conducted to estimate the impacts of above-ground vegetation and antecedent soil water condition on hydrology and sediment processes. A total of 9 small plots($1m{\times}0.5m$) were installed to represent different road surface conditions: no-vegetation(3 plots), vegetated surface(3 plots), and cleared vegetation surface(3 plots). Experiments were carried out on dry, wet, and very wet soil moisture conditions for each plot. Above ground parts of vegetation on road surface influenced significantly on surface runoff. Runoff from no-vegetation roads(39.24L) was greater than that from vegetated(25.05L), while cleared-vegetation condition is similar to no-vegetation roads(39.72L). Runoff rate responded in a similar way to runoff volume. Soil erosion was also controlled by land cover, but the magnitude is little than that of surface runoff. Even though slight differences among antecedent soil moisture conditions were found on both runoff and soil erosion, runoff rate and soil losses were increased in very wet condition, followed by wet condition. The experiments suggest that vegetation cover on forest road surface seems most effective way to reduce surface runoff and soil erosion during storm periods.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.328-330
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• 2003

The land cover of burned area has changed dramatically since Daxinganling forest fire in Northeastern China during May 6 ? June 4, 1987. This research focused on determining the burn severity and assessment of forest recovery. Burned severity was classified into three levels from June 1987 Landsat TM data acquired just after the fire. A regression model was established between the forest canopy closure from 1999 forest stand map and the NDVI values from June 2000 Landsat ETM+ data. The map of canopy closure was got according to the regression model. And vegetation cover was classified into four types according to forest closure density. The change matrix was built using the classified map of burn severity and vegetation recovery. Then the change conversions of every forest type were analyzed. Results from this research indicate: forest recovery status is well in most of burned scars; and vegetation change detection can be accomplished using postclassification comparison method.

• Journal of Environmental Science International
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• v.19 no.9
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• pp.1103-1108
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• 2010

This study was conducted to be used as basic data of environmental friendly construction planning by comparing and analyzing thermal environment, find particles and biotope area rate according to land cover types of outside space of schools located in Chung-ju. When meteorological factors were analyzed according to land cover types, for temperature planting area and paved area showed low-and high-temperature ranges, respectively, and relative humidity was negatively related with temperature as low-and high-temperature ranges corresponded to high-and low-humidity ranges, respectively. For Wet Bulb Globe Temperature Index (WBGT) by land cover types, it was observed to be artificial grass> bare land> natural grass. Find particles were different according to land cover types of playground with being bare land> artificial grass> natural grass in the order. Bare land playground, where there were artificial factors and no absorption of fine particles through stomata of leaves as a function of natural circulation, recorded the highest level of $39.8\;{\mu}g/m^3$ and the level was relatively higher compared to the levels by season in Chung-ju. Biotope area rate showed the order of M elementary school> K elementary school> C commercial high school. That was considered to be caused by the difference of land cover type of school playground accounting for a large part of a school.