간행물
한국환경과학회지 KCI 등재 Journal of Environmental Science International
- 발행기관 한국환경과학회
- 자료유형 학술지
- 간기 월간
- ISSN 1225-4517 (Print)2287-3503 (Online)
- 수록기간 1992 ~ 2023
- 주제분류 자연과학 > 자연과학일반 자연과학 분류의 다른 간행물
- 십진분류KDC 539DDC 628
권호리스트/논문검색
제31권 제9호 (2022년 9월) 7건
1.
2022.09
서비스 종료(열람 제한)
Global warming affects forests and their ecology. Diversity in the forest is a buffer that reduces the damage due to global warming. Mixed forests are ecologically more valuable as versatile habitats and are effective in preventing landslides. In Korea, most forests were created by simple afforestation with trees of evergreen species. Typically, evergreen trees are shallow-rooted, and deciduous trees are deep-rooted. Mixed forest tree roots grip the soil effectively, which reduces the occurrence of landslides. Therefore, improving the distribution of tree types is essential to reduce damage due to global warming. For this improvement, the investigation of tree types of the forest is needed. However, determining the tree type distribution of forests that are spread over wide areas is labor-intensive and time-consuming. This study suggests effective methods for determining the distribution of tree types in a forest that is spread across a relatively wide area. Using normalized difference vegetation index and RGB images from unmanned aerial vehicles, each evergreen and deciduous tree, and grassland area can be distinguished. The distinguished image determines the distribution of tree type. This method is effective compared to directly determining the tree type distribution in the forest by the use of manpower. The data from these methods could be applied to plan a mixed forest or to prepare for future damage due to global warming.
2.
2022.09
서비스 종료(열람 제한)
This study aims to review the differences in urban regeneration independently implemented by the government (Ministry of Land, Infrastructure, and Transport, MOLIT) and Seoul based on related laws and ordinances, and to draw out the implications of Korean urban regeneration’s directions. The results are as follows. First, Seoul has constantly responded to the revision of the Urban Regeneration Act by adjusting and specifying the contents of ordinances, and especially, there have been efforts to enhance regional characteristics suitably for the circumstances of Seoul. Second, in the urban regeneration of Seoul, the budgets including the matching ratio of national and local subsidies shall be changed according to the standards of the MOLIT in changing designating places after the selection of the urban regeneration by the ministry, and this procedure and these implementation methods cause confusion to Seoul and local governments. Third, there were differences in the results of comparing the budgets and support methods of the “Gaggum Housing Project” of Seoul and “New Deal Housing Repair Project” of the MOLIT, which caused conflicts due to the differences in the project implementation and support standards, and the arbitrary interpretation of the guidelines. Although the urban regeneration greatly contributed to the revelation and conservation of regional characteristics, it might be necessary to establish systems that can enhance citizens’ awareness and compensate the efficient contents needed for each region in the future.
3.
2022.09
서비스 종료(열람 제한)
This study is to examine how well the hydrologic model reproduces the dam collapse. To do this, A hydrologic model FLO-2D is being operated to reproduce dam collapse with rainfall data and surface data in a small dam. In order to examine the performance of the model, the simulation was compared and reviewed with the data collected through the field survey. The results show that it takes about 2 hours to reach 1 km downstream. Inundation areas are about 188,640 m2 by the simulation and the difference from the field investigation is about 6.1%. Ten representative points were selected from the areas where the simulation and the field survey did not match. The discrepancy is less than about 0.08 m and does not appear to be significant. This study will present basic information on disaster preparedness operation and planning to minimize damage caused by sudden collapse of agricultural soil dams in the future.
4.
2022.09
서비스 종료(열람 제한)
In this study, sediment cores were sampled from tidal flats (six sites) in the west and south coastal wetlands, the blue carbon stock in the tidal flat sediments was calculated, and the blue carbon stock characteristics and influencing factors were analyzed. The sediment particle size of the west coastal tidal flats was larger than that of the south coastal tidal flats, and the organic carbon content in the south coastal tidal flats was more than twice that of the west coastal tidal flats. Blue carbon stock per unit area was 28.4~36.8 Mg/㏊ on the west coastal tidal flats and 69.8~89.8 Mg/㏊ on the south coastal tidal flats, which was more than twice higher in the south coastal tidal flats than in the west coastal tidal flats. The total amount of blue carbon stock in the tidal flats was the highest in Suncheon Bay tidal flats at 153,626 Mg, and followed by Gomso Bay tidal flats at 141,750 Mg, Hampyeong Bay tidal flats at 58,420 Mg, Dongdae Bay tidal flats at 44,900 Mg, Cheonsu Bay tidal flats at 36,880 Mg, and Jinhae Bay tidal flats at 26,205 Mg. Blue carbon stock per unit area was higher in the south coastal tidal flats, but the total amount of blue carbon stock in the tidal flats was higher in the west coast. The slope of the regression function of blue carbon stock with respect to the organic carbon content in the tidal flat sediments was estimated to be about 0.05 to 0.07, and the slope of the regression function was higher in the west coastal tidal flats than in the south coastal tidal flats.
5.
2022.09
서비스 종료(열람 제한)
In order to investigate the characteristics of the effects of various emission sources such as ships around the Busan North Port area, PM2.5 samples were analyzed by SEM/EDS (scanning electron microscopy with energy dispersive x-ray spectrometer). In the port city Busan, the main emission source of PM2.5 is ships, and soot was observed as the main exhaust particles of a ship diesel engine. As a result of the individual particle analysis of PM2.5 at the sampling site, carbonaceous particles such as soot and water droplet-shaped, which are considered to be exhausted from ships, were constantly observed. And some spherical Fe-rich particles also appeared.
6.
2022.09
서비스 종료(열람 제한)
This study was carried out to provide basic data for logical forest management by developing a site index curve reflecting the current growth characteristics of Cryptomeria japonica stands in Korea. The height growth model was developed using the Chapman-Richards, Schumacher, Gompertz, and Weibull algebraic difference equations, which are widely used in growth estimation, for data collected from 119 plots through the 7th National Forest Inventory and stand survey. The Chapman-Richards equation, with the highest model fit, was selected as the best equation for the height growth model, and a site index curve was developed using the guide curve method. To compare the developed site index curve with that on the yield table, paired T-tests with a significance level of 5% were performed. The results indicated that there were no significant differences between the site index curve values at all ages, and the p-value was smaller after the reference age than before. Therefore, the site index curve developed through this study reflects the characteristics of the changing growth environment of C. japonica stands and can be used in accordance with the site index curve on the current yield table. Thus, this information can be considered valuable as basic data for reasonable forest management.
7.
2022.09
서비스 종료(열람 제한)
In this study, we improved the water-based condensation particle counter in Atmospheric Research Aircraft NARA and investigated the condensation particle number concentration over the Korean peninsula. Pump and set point information were changed to improve the instrument used by aircraft for observation. Ground-based observational result showed that the error between two instruments, which are water-based condensation particle counter and butanol-based condensation particle counter, was 4.7%. Aerial observational result revealed that the number concentration before improvement indicate large variation with unstable condition, whereas the number concentration after improvement indicate a reasonable variation. After improvement, the number concentration was 706±499 particle/㎤ in the West Sea and 257±80 particle/㎤ in Gangwon-do, and these are similar to the concentration range reported in previous studies. Notably, this is the first attempt to use aerial observation with water-based condensation particle counter to investigate condensation particle number concentration.
