• Journal of the Korean Association of Geographic Information Studies
• /
• v.22 no.3
• /
• pp.21-36
• /
• 2019

Dead fuel moisture content is a key variable in fire danger rating as it affects fire ignition and behavior. This study evaluates simple regression models estimating the moisture content of standardized 10-h fuel stick (10-h FMC) at three sites with different characteristics(urban and outside/inside the forest). Equilibrium moisture content (EMC) was used as an independent variable, and in-situ measured 10-h FMC was used as a dependent variable and validation data. 10-h FMC spatial distribution maps were created for dates with the most frequent fire occurrence during 2013-2018. Also, 10-h FMC values of the dates were analyzed to investigate under which 10-h FMC condition forest fire is likely to occur. As the results, fitted equations could explain considerable part of the variance in 10-h FMC (62~78%). Compared to the validation data, the models performed well with R2 ranged from 0.53 to 0.68, root mean squared error (RMSE) ranged from 2.52% to 3.43%, and bias ranged from -0.41% to 1.10%. When the 10-h FMC model fitted for one site was applied to the other sites, $R^2$ was maintained as the same while RMSE and bias increased up to 5.13% and 3.68%, respectively. The major deficiency of the 10-h FMC model was that it poorly caught the difference in the drying process after rainfall between 10-h FMC and EMC. From the analysis of 10-h FMC during the dates fire occurred, more than 70% of the fires occurred under a 10-h FMC condition of less than 10.5%. Overall, the present study suggested a simple model estimating 10-h FMC with acceptable performance. Applying the 10-h FMC model to the automatic mountain weather observation system was successfully tested to produce a national-scale 10-h FMC spatial distribution map. This data will be fundamental information for forest fire research, and will support the policy maker.

• Journal of Microbiology and Biotechnology
• /
• v.2 no.1
• /
• pp.66-71
• /
• 1992

The ecological distribution of endomycorrhizas in evergreen woody species native to the evergreen forest ecosystem of Tadohae-haesang National Park in southern Korea in February, 1989 was studied. The abundance and diversity of vesicular-arbuscular (VA) mycorrhizal fungi were also determined. The spore densities ranged from 14 to 326 per 100 g of soil. Most of the spores of mycorrhizal fungi collected from 25 soil samples belonged to the genera Glomus and Gigaspora. The frequency and number of spores in Camellia japonica varied with location. Spores belonging to the genus Gigaspora were not found in Camellia japonica in Yesongri evergreen forests adjacent to the sea. Glomus sp. was the major constituent of the spore assemblage at this site. The most abundant species in Camellia japonica in the Yesongri evergreen forests in Pogildo was Glomus borealis. In the soil of a mountain at Buwhangri, in the central location of the island at an elevation of 250 m, Gigaspora sp. was present and Glomus sp. was a major constituent of the spore assemblage. In the urban area of Haenam spore densities were much higher than in the Pogildo area. The most abundant species in Camellia japonica in the urban area of Haenam was Gigaspora sp..

• Journal of the Korean Association of Geographic Information Studies
• /
• v.22 no.1
• /
• pp.154-167
• /
• 2019

As urban heat environment problems occur due to climate change, urban thermal environmental problems such as heat waves and tropical nights are becoming more serious in cities. In South Korea, forest areas favorable for generating cold air account for about 63 percent of the land area. Furthermore, the Jeongmaek, the axis of the main mountain ranges of Korea, is located close to the cities. Hence, the management of cold air is an effective way to improve the thermal environment of Korean cities. We selected the Nak-nam Jeongmaek located in the southern part of Korean Peninsular as well as two cities (Jinju-si and Sancheong-gun) located at the Jeongmaek to analyze its cold air characteristics and suggest management strategies of cold air. We used KALM (Kaltluftabflussmodell), a cold air simulation model developed in Germany and identified both the cold air flow and the height of cold air layer generated during 6 hours at night. As a result, the cold air flow generated in the Jeongmaek became clear and the height of cold air layer increased with time. Based on the results, we proposed management plans to maintain and expand the cold air flow. For example, forest areas with active cold air generation were designated as 'cold air conservation areas', and areas requiring management for good cold air flow were as 'cold air management areas'. This study is expected to be useful for establishing systematic urban ventilation plan to improve thermal environment in Korea cities.

• The Journal of Engineering Geology
• /
• v.28 no.1
• /
• pp.47-59
• /
• 2018

At present, there has been a wide range of studies on debris flow in Korea, more specifically, on rainfall characteristics that trigger debris flow including rainfall intensity, rainfall duration, and preceding rainfall. the prediction of landslide / debris flow relies on the criteria for landslide watch and warning by the Korea Forest Service (KFS, 2012). Despite this, it has been found that most incidents of debris flow were caused by rainfall above the level of landslide watch, maximum hourly rainfall, extensive damage was caused even under the watch level. Under these circumstances, we calculated a rainfall triggering index (RTI) using the main factors that trigger debris flow-rainfall, rainfall intensity, and cumulative rainfall-to design a more sophisticated watch / warning criteria than those by the KFS. The RTI was classified into attention, caution, alert, and evacuation, and was assessed through the application of two debris flow incidents that occurred in Umyeon Mountain, Seoul, and Cheongju, Inje, causing serious damage and casualties. Moreover, we reviewed the feasibility of the RTI by comparing it with the KFS's landslide watch / warning criteria (KFS, 2012).

• Environmental and Resource Economics Review
• /
• v.28 no.1
• /
• pp.61-93
• /
• 2019

This study is to apply Hedonic Price Method in analyzing residents' preferences for three types of urban green space (UGS, rivers, urban parks, and forests) near the apartment complexes in Seoul. Based on hedonic price function estimation results, residents in Seoul preferred for the urban amenity that was provided by the view and accessibility (in terms of both within 10 minutes and distance) of rivers and urban parks near the apartment complexes, but not forests. The annual benefits calculated using the shadow prices are about 550~600 thousand won for the urban park views and about 800 thousand won for the accessibility, which is 2-3 times higher than river views and accessibility. On the other hand, forest views and accessibility did not have significant effects on apartment prices, except the view of Bukhan mountain for the residents of Gangbuk area. Based on the empirical results, Seoul residents' preferences for urban parks would have important implications for the urban park sunset program that will be initiated from July 2020.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.23 no.4
• /
• pp.47-58
• /
• 2020

This study was done to evaluate resources distributed around the Nakdong-Jeongmaek which is the eastern ridge line of the Nakdong-river basin with 437km in length. Here we found and/or searched for thousands of resources within each of 210 villages around the ridge, which were divided into six categories including landscape, natural park, protected area, history, tourism and biodiversity. An inventory was also created using an attribute table in a shape file for identifying the spatial location and property for every resource existing in each village. Each of fields for six-typed resources has 210 records representing each village and resources within it. If a resource exists in a village, '1' is assigned for its existence in its corresponding record. Otherwise, '0' is assigned for its non-existence in the record. The number of '1' on six records for a village is meaning the number of resources contained within a village, which can be a barometer to decide the properties of each village. In this study, we found five core villages containing all kind of resources in it, while 52 villages were found having only a single type of resources within it. The other villages were known to have multiple resources like having two or more ones.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.19 no.3
• /
• pp.89-101
• /
• 2016

This study examined spatial disposition of wildlife highway mortality using road-kill GIS database and Naver panoramic 360 degree views to find out which habitat and road variables most influenced road-kill numbers for each mammal species and how the landscape and road elements are connected on highway. Road-kills on Yeongdong(YD) and Jungbu highway(JB) generally tended to be higher in natural barren, grassland and cropland due to its value of preferred habitats of nocturnal and multihabitat species like water deer(Hydropotes inermis argyropus), raccoon(Nyctereutes procyonoides) and hare(Lepus coreanus). Land cover in YD showed no difference between species (p=0.165) while JB did by species (p=0.001). This may be explained by disparate landscape between mountain and urban or the fact that YD in long term operation might have enabled consistent crossing pattern compared to JB experiencing continuous extension works which may in turn have deviated the road crossing. Although road-kill prevention effect of local topography alone was appreciable, compared to less significant or ineffective fence and guardrail, gentle slope declining in a direction to the road turned out to offset the preventive effect of juxtaposed fence. Furthermore, green patches on road near intersection were deemed a visual stepping stone facilitating wildlife attempted crossing and local roads juxtaposed with a highway were especially left defenceless to road-kill without road barriers.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.6 no.3
• /
• pp.46-55
• /
• 2003

This study aims to evaluate the Ulsan city residents' perception and satisfaction with open spaces and cityscape after consideration in the side of getting primary data for the city open spaces policy and Green Plan for Ulsan city. In this study, low data was gathered by questionnaires survey with stratified random sampling method. Questionnaires were designed by several sets of variables such as behavioral patterns, satisfactions for open spaces and user's demographic variables. Data were analyzed by descriptive statistics, cross-tabulation and regression analysis. The main results of this study can be summarized as follows : 1. In overage the residents were slightly satisfied with park open spaces. There were good and poor park open spaces. in the perceptions of citizens as follows : 'nearby mountain and open spaces', 'rail side green area' were high satisfactory, and 'riverside', 'green qualities' were low in satisfaction. 2. In overage the residents were slightly satisfied with cityscape. There were good and poor cityscape in the perceptions of citizens as follows : 'nearby forest in and open spaces', 'night scape of an urban center' were high satisfactory, and 'streetscape', 'appearances of high-rise buildings' were low in satisfaction. 3. As a results of regression analysis predictable variables for satisfaction with Park and Open spaces were : 'open spaces by the public', 'open spaces by neighbor', 'grande open spaces', 'open spaces of residence'. 4. As a results of regression analysis predictable variables for satisfaction with cityscape were : 'Central Business District(C.B.D) and nearby mountain and open spaces', 'residence and streetscape', 'riverside and park green open spaces'.

• Journal of the Korean Solar Energy Society
• /
• v.40 no.4
• /
• pp.35-44
• /
• 2020

Currently, various policies regarding ecofriendly vehicles are being proposed to reduce carbon emissions. In this study, the required areas for charging electric vehicle (EV) batteries using electricity produced by photovoltaic (PV) power plants were estimated. First, approximately 2.4 million battery EVs, which represented 10% of the total number of vehicles, consume approximately 404 GWh. Second, the power required for charging batteries is approximately 0.3 GW, and the site area of the PV power plant is 4.62 ㎢, which accounts for 0.005% of the national territory. Third, from the available sites of buildings based on the region, Jeju alone consumes approximately 0.2%, while the rest of the region requires approximately 0.1%. Fourth, Seoul, which has the smallest available area of mountains and farmlands, utilizes 0.34% of the site for PV power plants, while the other parts of the region use less than 0.1%. The results of this study confirmed that the area of the PV power plant site for producing battery-charging power generated through the supply of EVs is very small. Therefore, it is desirable to analyze and implement more specific plans, such as efficient land use, forest damage minimization, and safe maintenance, to expand renewable energy, including PV power.

• Korean Journal of Remote Sensing
• /
• v.16 no.4
• /
• pp.367-373
• /
• 2000

Natural and artificial land features are very dynamic, changing somewhat repidly in our lifetime. It is important that such changes are inventoried accurately so that the physical and human processes at work can be more fully understood. Change detection is a technique used to determine the change between two or more time periods of a particular object of study. Change detection is an important process in monitoring and managing natural resources and urban development because it provides quantitative analysis of the spatial distribution in the population of interest. The purpose of this research is to detect environmental changes surrounding an area of Mountain Moscow, Idaho using Landsat Thematic Maper (TM) images of (July 8, 1990 and July 20, 1991). For accurate classification, the Image enhancement process was performed for improving the image quality of each image. A SPOT image (Aug. 14, 1992) was used for image merging in this research. Supervised classification was performed using the maximum likelihood method. Accuracy assessments were done for each classification. Two images were compared on a pixel-by-pixel basis using the post-classification comparison method that is used for detecting the changes of the study area in this research. The 'from-to' change class information can be detected by post classification comparison using this method and we could find which class change to another.