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.

광물의 격자구조가 특정한 방향성을 보이는 격자선호방향은 광물의 변형 조건에 따라 다르기 때문에, 해당 광물과 이를 포함한 암석의 변형 조건을 연구하는데 있어 유용하다. 이번 연구에서는 경기육괴의 남서 부지역에 위치한 유구읍 추계리 금계산 일대의 각섬암류를 채취하여 암석내부 각섬석과 장석의 격자선호방향 을 후방산란전자회절 기기를 사용하여 분석하였다. 분석결과 유구지역의 각섬석에서는 type IV와 type I 두가 지 격자선호방향이 관찰되었다. 유구지역의 각섬암류 내 각섬석은 격자선호방향에 관계없이 강체회전에 의해 변형을 받은것으로 보이며, 암석의 변형정도가 결정입도와 격자선호방향에 영향을 준 것으로 생각된다. 각섬 석의 결정입도가 커서 변형을 가장 작게 받은것으로 생각되는 시료에서는 각섬석이 강한 type I 격자선호방향 을 보여주었다. 이에 반해, 각섬석의 결정입도가 작아 고변형을 받은 것으로 생각되는 시료들에서는 각섬석이 약한 type IV 격자선호방향을 보여 주었다. 유구지역에서 관찰되는 다양한 암석의 변형정도는 각섬암류와 인 접해있는 페리도타이트에서도 관찰된 바 있어, 유구지역이 다양한 수준의 변형을 받았음을 지시한다.

한반도 동남부에서 가장 규모가 큰 마이오세 포항분지의 남서부를 대상으로 상세한 지질도 작성과 지질구조를 분석하여 분지 발달사를 해석하였다. 포항분지 남서부는 북북동 방향의 분지 내 지구내지루에 의해 기하와 변형사가 서로 다른 서쪽의 보문구역과 동쪽의 오천구역으로 나누어진다. 보문구역은 포항분지 초기 확장 이후 거의 변형되지 않은 반면, 오천구역은 충전물의 퇴적 이후에도 후기 변형이 지속·중첩된 지역이다. 따 라서 보문구역은 포항분지 최초 확장 형식에 대한 중요한 정보를 제공한다. 보문구역은 북북동 방향의 정단 층들과 북북서(북서) 방향의 우수향 주향이동단층 분절들이 지그재그로 이어진 서편 경계단층에 의해 침강이 주도되었으며, 이 경계단층은 남쪽으로 한반도 동남부 마이오세 지각변형의 서쪽 한계선이며 우수향 주향이 동성 주변위대로 알려진 연일구조선과 연결된다. 따라서 포항분지는 17-16.5Ma 경 활동을 시작한 연일구조 선 북쪽 말단에 우향스텝 형태로 생성된 북북동 방향의 정단층 또는 사교이동단층에 의해 서북서-동남동 방 향으로 확장된 횡인장단층말단분지로 최초 침강된 것으로 해석된다. 이로 인해 보문구역에는 서쪽으로 갈수록 분 지의 깊이가 더 깊어지는 북북동 방향의 비대칭 지구 또는 반지구가 생성되었다. 이후 포항분지의 확장과 변 형은 오천구역을 포함하는 보다 동편 지역으로 이동하였다.

In this study, the contributions of emissions (foreign and domestic) and atmospheric physical and chemical processes to PM2.5 concentrations were evaluated during a high PM2.5 episode (March 24-26, 2018) observed on the Jeju Island in the spring of 2018. These analyses were performed using the community multi-scale air quality (CMAQ) modeling system using the brute-force method and integrated process rate (IPR) analysis, respectively. The contributions of domestic emissions from South Korea (41-45%) to PM2.5 on the Jeju Island were lower than those (81-89%) of long-range transport (LRT) from China. The substantial contribution of LRT was also confirmed in conjunction with the air mass trajectory analysis, indicating that the frequency of airflow from China (58-62% of all trajectories) was higher than from other regions (28-32%) (e.g., South Korea). These results imply that compared to domestic emissions, emissions from China have a stronger impact than domestic emissions on the high PM2.5 concentrations in the study area. From the IPR analysis, horizontal transport contributed substantially to PM2.5 concentrations were dominant in most of the areas of the Jeju Island during the high PM2.5 episode, while the aerosol process and vertical transport in the southern areas largely contributed to higher PM2.5 concentrations.

The effect of coupled data assimilation (DA) on the meteorological prediction in the west coastal region of Korea was evaluated using a coupled atmosphere-ocean model (e.g., COAWST) in the spring (March 17􎂡26) of 2019. We performed two sets of simulation experiments: (1) with the coupled DA (i.e., COAWST_DA) and (2) without the coupled DA (i.e., COAWST_BASE). Overall, compared with the COAWST_BASE simulation, the COAWST_DA simulation showed good agreement in the spatial and temporal variations of meteorological variables (sea surface temperature, air temperature, wind speed, and relative humidity) with those of the observations. In particular, the effect of the coupled DA on wind speed was greatly improved. This might be primarily due to the prediction improvement of the sea surface temperature resulting from the coupled DA in the study area. In addition, the improvement of meteorological prediction in COAWST_DA simulation was also confirmed by the comparative analysis between SST and other meteorological variables (sea surface wind speed and pressure variation).

This study investigated characteristics of meteorological parameters and ionic components of PM2.5 during Asian dust events on November 28 and 30, 2018 at Busan, Korea. The seasonal occurrence frequencies of Asian dust during 1960∼2019 (60 years) were 81.7% in spring, 12.2% in winter, and 6.1% in autumn. Recently, autumn Asian dust occurrence in Busan has shown an increasing trend. The result of AWS (automatic weather station), surface weather chart, and backward trajectory analyses showed that the first Asian dust of Nov. 28, 2018, in Busan came with rapid speed through inner China and Bohai Bay from Mongolia. The second Asian dust of Nov. 30, 2018, in Busan seems to have resulted from advection and deposition of proximal residual materials. These results indicated that understanding the characteristics of meteorological parameters and ionic components of PM2.5 during Asian dust events could provide insights into establishing a control strategy for urban air quality.

This research investigated the effect of the eruption of Japan Sakurajima volcano on the concentration of ultrafine particle when the north Pacific high pressure exists in the Busan in summer. As a result of analyzing the forward trajectory using the HYSPLIT model, the air parcel from Sakurajima volcano passed through the sea in front of Busan at 1500 LST on July 17, 24 hours after the volcanic eruption. As a result of analyzing the PM10 and PM2.5 concentrations in the Busan for two days from July 16 to 17, 2018, the Sakurajima eruption in Japan, it can be seen that there was a high increase in PM10 and PM2.5 concentrations compared to the previous day. As a result of analyzing the backward trajectory, the air mass that reached Busan at 1300 LST on July 17, 2018 has moved near the Sakurajima volcano at 1,500 m, 2,000 m, and 3,000 m. The concentration of SO4 2- in PM2.5, the concentration of all three stations in Busan showed a sharp increase from 1000 LST on July 17th. Looking at the NH4 + concentration in PM2.5, it shows a very similar variation trend to SO4 2-, and the correlation coefficient between the two components is 0.96 for Jangrimdong and Yeonsandong, and 0.85 for Busan New Port. Looking at the NO3 - concentration in PM2.5, the same high concentrations as SO4 2- and NH4 + were not observed in the afternoon of July 17th.

To identify rice (Oryza sativa L.) cultivars suitable for Italian ryegrass (Lolium multiflorum Lam.)–rice double cropping systems, we investigated the yield and grain quality of four different midseason maturing rice cultivars (‘Daebo’, ‘Haepum’, ‘Haiami’, and ‘Samdeog’) and four midseason-to-late maturing rice cultivars (‘Hyunpoom’, ‘Saeilmi’, ‘Saenuri’, and ‘Samkwang’) in single rice cropping and Italian ryegrass–rice double cropping systems in paddy fields of Miryang, South Korea. We found that organic matter and available P2O5 content slightly decreased, whereas Na content increased, in the soil where Italian ryegrass was cultivated during winter compared to that in the soil that remained fallow during winter. The pH, electrical conductivity, organic matter, and contents of K+, Ca2+, Mg2+, and Na+ decreased, whereas the available P2O5 content slightly increased, in the soil where rice was harvested in both single and double cropping systems. However, compared to the optimum soil conditions for rice cultivation, available P2O5 and K+ content were high and Mg2+ content was low in both single and double cropping systems. At the heading stage, the culm length and leaf color slightly increased in most of the rice cultivars, whereas the panicle length and number slightly decreased, in the double cropped system. After harvesting, spikelet number and milled rice yield did not show a significant difference between single and double cropping systems. However, the ripened grain rate and weight per thousand grains increased slightly in the ‘Saeilmi’ and ‘Samkwang’ cultivars but remained either stable or slightly low in other cultivars in the double cropping system. The milled rice yield was high (> 500 kg/10a) in ‘Daebo’ and ‘Haepum’ among midseason maturing rice cultivars, and in ‘Saeilmi’ and ‘Saenuri’ among midseason-to-late maturing rice cultivars, in both single and double cropping systems. The head rice rate was high in midseason maturing rice cultivars in the double cropping systems, reaching > 70% in ‘Haepum’ and ‘Haiami’ cultivars, whereas it decreased in most midseason-to-late maturing rice cultivars (excluding ‘Samkwang’ cultivar), in double cropping systems. Particularly, it exceeded > 70% in the ‘Saenuri’ cultivar in both single and double cropping systems. The protein content in milled rice increased, whereas the amylose content either remained stable or slightly increased, in double cropping systems. The Toyo taste value decreased in all midseason-to-late maturing rice cultivars and slightly increased in the ‘Daebo’ and ‘Haiami’ cultivars among midseason maturing rice cultivars in double cropping systems. However, Toyo taste values in the ‘Haepum’, ‘Haiami’, and ‘Saenuri’ cultivars exceeding > 80% in both single and double cropping systems. Therefore, we recommend ‘Haepum’, ‘Haiami’, and ‘Saenuri’ cultivars as candidates for Italian ryegrass–rice double cropping systems due to high yield, head rice rate, and Toyo taste value.

The purpose of this study is to evaluate the vegetation recovery status of Mudeungsan National Park Jungmeorijae, Jeungsimsa district restoration site, and the Shimwon Valley ecological landscape restoration site in Jirisan National Park. Compared to the control plots, the Jungmeorijae restoration site was analyzed to have height growth of about 73.5%, the average species diversity index of about 75.2%. and the average similarity index was recovered to 7.75%. In the case of the restoration site in Jeungsimsa district, the height growth compared to the control plots was about 69.2%, the average species diversity index was about 55.0%. and the average similarity index was recovered to 25.65%. In the case of the Shimwon Valley ecological landscape restoration area, the height growth compared to the control plots was about 32.6%, the average species diversity index about 176.7%. and the average similarity index was recovered to 0.85%. The restoration site of the Jeungsimsa district was planted with relatively large trees during restoration work, and it took a relatively long time(20 years). Also, the site had less limiting factors due to the low elevation, allowing the degree of vegetation recovery to be higher than that of other sites.

This study focused on the characteristics of manure in five beef cattle farms and two breeding farms in Hanwoo centered in Gyeongsangbuk-do province. The results of analysis and evaluation are as follows; First, the pH of manure in all the farms in this study was within the appropriate range of 8.81 to 9.45. Second, the dry matter content varied from 44.7% to 70.5% for all the farms. Third, the total nitrogen content in all the farms was 2.05-3.04%, which is higher than the reported range; however, it could play a role as a soil improvement agent when used as compost. Fourth, although the exact range of ammonia-N (VBN) content was not reported, results analyzed in all the farms showed that the level of impact on the environment was insignificant. In conclusion, soil and environment improvement effects are expected to be effective if the manure at Hanwoo farms in the Gyeongbuk area are used as compost through appropriate management.

From January 1, 2020, the International Maritime Organization has implemented a global regulation, known as IMO 2020, to reduce the sulfur content in fuel oil of ships from 3.5% to 0.5%. In this study, we used data from air monitoring stations to evaluate the change in air quality at New Port and North Port in Korea areas after the regulation was implemented. The concentration of SO2 and NO2 was higher in the port areas than in the surrounding areas due to exhaust gas from ships and vehicles. However, the SO2 concentration decreased by more than 50% in the port area, demonstrating the efficiency and positive effect of the IMO 2020 sulfur limit.

In this study, water resource topics, infrastructure, water supply, users, and economic indicators based on statistical annual standards for evaluating water welfare were selected by examining domestic and foreign water resource-related indicators. The level of water welfare was evaluated relative to 23 cities and counties in Daegu and Gyeongsangbuk-do using data from the Statistical yearbook, and places with high value of indicators urbanization and large populations were excellent in the infrastructure field, but overall analysis showed that small and medium-sized cities had higher levels. It is judged that it is necessary to develop continuous research and indicators that can evaluate and quantify the level of physical welfare that the people can feel by utilizing the results of this study. In future studies, it is necessary to systematically evaluate the level of water welfare by local governments in Korea through more diverse evaluation items and detailed indicators for each item so that it can be used as basic data for realizing water welfare.

This study investigated the variations in monthly PM2.5 concentrations and their characteristics at the sampling site (35.075°N, 129.080°E) around the Busan seaport area for six months (from August 2020 to January 2021). Monthly PM2.5 concentrations in the filtered samples ranged from 8.4 to 42.3 ㎍/m3 (average=19.6±8.2 ㎍/m3, n=50) and were generally high in August, December, and January, and low in September, October, and November. The variations of monthly PM2.5 concentrations showed similar patterns to those of the neighboring national air quality monitoring sites. The contents of Total Carbon (TC), Organic Carbon (OC), Elemental Carbon (EC), and OC/EC ratios in PM2.5 showed large variability during the study period. The OC/EC ratios ranged from 4.2 to 34.4, suggesting that the relative contributions of OC and EC to the PM2.5 concentrations changed temporally and might be related to their formation sources. Variations in the chemical components of and particle size distributions in PM2.5 showed that high PM2.5 concentrations were affected by various sources, such as sea salt and ship emission. The precursor gas concentrations were discussed in terms of monthly variations and their contributions to PM2.5 concentrations. However, further research is needed to understand the characteristics and behaviors of PM2.5 concentrations around the Busan seaport area.

The purpose of this study is to elucidate the spatio-temporal characteristics of ultrafine dust generation in East Asia and the synoptic climate patterns related to its dispersal which has its adverse effects on public health across East Asia. To achieve this purpose, Level 3 monthly Aerosol Optical Depth (AOD) data extracted from MODIS satellite imagery (MOD08_M3) representing particle matters less than 2.5 micrometer (PM2.5) and the NCEP-NCAR reanalysis I upper-level climatic data associated with the exacerbation of ultrafine dust problem are analyzed for the recent 20-year (2001-2020) period. Analyses of long-term average MOD08 data show that high AOD value exceeding 0.5 or more frequently occurred in populous cities in East Asia but mainly in the vicinity of densely populated large rivers and the eastern lowlands in China between mid-winter and mid-spring, which is attributable to the accumulation effects of continuous fossil fuel consumption for heating and manufacturing. Despite the overall decreasing trend of ultrafine dust across China in the 2010s, the weakened westerlies in the warmer climate as well as its continuous generation from the densely populated industrial regions of China provide a favorable synoptic climate condition for frequent severe ultrafine dust problems across East Asia including South Korea. These results indicate that ultrafine dust from China is a long-lasting transboundary environmental problem across East Asia, which needs long-term international cooperation in developing the sustainable policies.

We projected the temperature changes in the mid-21st century with Representative Concentration Pathway (RCP) 4.5 and RCP8.5 using the temperature data simulated by four regional climate models (RCMs: WRF, CCLM, MM5, RegCM4) in Korea. The simulation area and spatial resolution of RCMs were the CORDEXEA (COordinated Regional Climate Downscaling Experiment-East Asia) area and 25 km, respectively. We defined the temperature change as the difference (ratio) between the average annual temperature (IAV: Interannual Variation) over the projected 25 years (2026-2050) and that over the present 25 years (1981-2005). The fact that the average annual temperature bias of the four RCMs is within ±2.5°C suggests that the RCM simulation level is reasonable in Korea. Across all RCMs, scenarios, and geographic locations, we observed increased temperatures (IAV) in the mid-21st century. In RCP4.5 and RCP8.5, 1.27°C and 1.57°C will be increased by 2050, respectively. The ensemble suggests that the temperature increase is higher in winter (RCP4.5: 1.36°C, RCP8.5: 1.75°C) than summer (RCP4.5: 1.25°C, RCP8.5: 1.49°C). Central Korea exhibited a higher temperature increase than southern Korea. A slightly larger IAV is expected in the southeastern region than in the Midwest of Korea. IAV is also expected to increase significantly in RCP4.5 (summer) than in RCP8.5 (winter).

The physicochemical properties of soil and the yield and quality of rice (Oryza sativa L. cv. Sailmi) were assessed using Italian ryegrass (Lolium multiflorum Lam. cv. Kowinearly)-rice double cropping systems in the paddy fields at Goseong and Miryang in southern Korea. The average temperatures during the ripening period were approximately 1 °C higher than the optimal temperature for rice ripening and the sunshine duration was reduced by frequent rainfall. Consequently, it was slightly below the optimal conditions required for rice ripening. In the soil at Goseong, winter Italian ryegrass cropping increased the pH, electrical conductivity, and the contents of organic matter, total nitrogen (T-N), available P2O5, K, Ca, and Mg than winter fallowing. Particularly, the contents of T-N and available P2O5increased significantly. In the soil at Miryang, Italian ryegrass slightly increased the electrical conductivity and the T-N, Mg, and Na contents. Therefore, winter Italian ryegrass cropping improved the physicochemical properties of paddy soils; however, Italian ryegrass-rice double cropping slightly reduced the culm length at both Goseong and Miryang, without markedly changing the panicle length or number compared to fallow-rice cropping. Furthermore, at Goseong, Italian ryegrass-rice double cropping slightly decreased the spikelet number and milled rice yield, and increased the ripened grain rate; however, at Miryang, contrasting results were observed. In addition, fallow-rice cropping revealed no differences in the head rice or opaque rice rates. The protein content was slightly increased in Italian ryegrass-rice double cropping, without significant changes in the amylose content or Toyo value, compared to that in fallow-rice cropping. The peak and breakdown viscosities were slightly decreased. These results indicate that winter Italian ryegrass cropping might alter rice taste but may not exhibit remarkable negative effects on rice cultivation. Therefore, Italian ryegrass-rice double cropping system is recommended for paddy fields in southern Korea. Nevertheless, to increase the rice yield and quality, fertilization standards for rice cropping that consider the changes in the T-N and organic matter contents in paddy fields caused by winter Italian ryegrass cropping need to be established.

To analyze the effects of PM10 and PM2.5 on daily mortality cases, the relations of death counts from natural causes, respiratory diseases, and cardiovascular diseases with PM10 and PM2.5 concentrations were applied to the generalized additive model (GAM) in this study. From the coefficients of the GAM model, the excessive mortality risks due to an increase of 10 μg/m3 in daily mean PM10 and PM2.5 for each cause were calculated. The excessive risks of deaths from natural causes, respiratory diseases, and cardiovascular diseases were 0.64%, 1.69%, and 1.16%, respectively, owing to PM10 increase and 0.42%, 2.80%, and 0.91%, respectively, owing to PM2.5 increase. Our result showed that particulate matter posed a greater risk of death from respiratory diseases and is consistent with the cases in Europe and China. The regional distribution of excessive risk of death is 0.24%–0.81%, 0.34%–2.6%, and 0.62%–1.94% from natural causes, respiratory diseases, and cardiovascular diseases, respectively, owing to PM10 increase, and 0.14%–1.02%, 1.07%–3.92%, and 0.22%–1.73% from natural causes, respiratory diseases, and cardiovascular diseases, respectively, owing to PM2.5 increase. Our results represented a different aspect from the regional concentration distributions. Thus, we saw that the concentration distributions of air pollutants differ from the affected areas and identified the need for a policy to reduce damage rather than reduce concentrations.

In this study, the bathymetric data acquired from 2018 to 2020 and the precipitation and suspended sediment data were analyzed for changes in bathymetry owing to the discharge from the Nakdong River barrier and environmental factors, especially the torrential rain in 2020. Sediment erosion and deposition processes are repeated because of complex environmental factors such as discharge from the Nakdong River barrier and the influence of waves generated from the external sea. In the first half of the year after the dry season, bathymetric data showed relative erosion trends, whereas in the second half after the flood season, deposition trends were identified owing to the increase in sediment transport. However, the data from the second half of 2020 showed a large amount of erosion, resulting in tendencies different to those of erosion in the first half and deposition in the second half of the year. This result is judged to be influenced by the weather in the summer of 2020. The torrential rain in the summer of 2020 resulted in a higher force of erosion than that of deposition. In summary, the tendency for erosion is more significant than that of sedimentation, especially in the main channel area of the Nakdong River.

This research investigated the characteristics of fine particles during cold front passage in Busan, on March 19, 2020. The cold front speed was 17.4 m/s (about 63k km/hr), moving from the northwest to the southeast, and with a width of about 64 km. The backward trajectory analysis showed that a southern sea air parcel flowed into Busan before the cold front passage, carrying continental materials from China transported into Busan after cold front passage. The PM10 concentration in Busan showed a rapid increase after passing through the cold front, with PM2.5 showing a high concentration during cold front passage. The PM2.5/PM10 ratio was 0.10 - 0.30. When the cold front passed, SO4 2-, NO3 -, Ca2+, NH4 +, Na+, and K+ in PM2.5 showed a rapid increase, with SO4 2- showing the most significant increase. These results indicated that understanding the characteristics of fine particles during cold front passage in Busan could provide insight into establishing a strategy to control urban air quality.

This research investigated the characteristics of fine particle concentration and ionic elements of PM2.5 during sea breeze occurrences during summertime in Busan. The PM10 and PM2.5 concentrations of summertime sea breeze occurrence days in Busan were 46.5 ㎍/㎥ and 34.9 ㎍/㎥, respectively. The PM10 and PM2.5 concentrations of summertime non-sea breeze occurrence days in Busan were 25.3 ㎍/㎥ and 14.3 ㎍/㎥, respectively. The PM2.5/PM10 ratios of sea breeze occurrence days and non-sea breeze occurrence days were 0.74 and 0.55, respectively. The SO4 2-, NH4 +, and NO3 - concentrations in PM2.5 of sea breeze occurrence days were 9.20 ㎍/㎥, 4.26 ㎍/㎥, and 3.18 ㎍/㎥ respectively. The sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) of sea breeze occurrence days were 0.33 and 0.05, respectively. These results indicated that understanding the fine particle concentration and ionic elements of PM2.5 during sea breeze summertime conditions can provide insights useful for establishing a control strategy of urban air quality.