고준위폐기물을 지하 500m의 화강암 암반의 처분장에 장기간(약 10,000년 동안) 처분 시 폐기물에서 발생하는 열에 의하여 처분용기 및 처분용기를 감싸고 있는 주위 구조물(벤토나이트 버퍼, 암반 등)의 처분시간 경과에 따른 온포분포 변화를 알아내는 것은 처분장 설계를 위하여 매우 중요하다. 본 논문에서는 수치해석기법을 이용하여 고준위폐기물에서 발생하는 열에 의한 처분용기 및 벤토나이트 버퍼, 처분동굴을 포함하는 복합구조물의 온도분포 변화를 구하였다. 특히 처분 후 500년의 처분시간 경과에 따른 복합구조물의 온도분포 해석을 수행하여 온도분포 변화를 구하였다. 시간에 따른 온도분포 변화에 대한 해석결과를 분석한 결과 처분장 각 구성부분별로 차이는 있으나 처분초기부터 구성부분별로 각각 다르게 온도가 증가하는데 가장 늦은 부분은 150년까지 완만하게 온도가 증가하다가 그 이후에는 온도가 서서히 감소하는 것으로 나타났다.

본 연구의 목적은 1980년에서 2000년 사이 한국의 노인인구의 지역적 변화 유형을 분석하는데 있다. 특히 본 연구는 지도학적인 측면에서 작성된 choropleth map에 의한 변화와 노인인구의 공간적 특성의 변화를 조사하고자 한다. 연구 자료는 1980년도, 1990년도, 2000년도의 한국 인구 센서스 결과를 이용하였다. 한국의 노인 인구는 유례를 찾아 볼 수 없을 정도로 급속히 증가하고 있다. 노인인구의 문제는 도시보다 농촌이 더욱 심각하다. 농촌의 인구는 감소하고 도시의 인구는 지속적으로 증가하고 있으나, 노인 인구 비율의 증가는 농촌이 도시에 비해 매우 높다. 한국의 노인인구분포는 생애주기의 변화, 정부에 의해 진행되는 도시지역의 발달, 주택 정책 등에 의해 영향을 받고 있다. 한국은 가까운 장래에 보다 더 심각한 새로운 도전을 받게 될 것이다.

There were few data for the distribution of the indicator organisms in the commercial plant foods, and for the normal flora and for the foodborne agents within the country. First of all it must be investigated the distribution of the indicator organisms. And also it is very important to prepare the sanitation criteria for the plant foods through the microbiological e×amination and the investigation of tendency to change of the indicator organisms according to the storage temperature and period. The average number of total viable counts for grains was 2.9 × 10^5/g, psychrophilic bacteria 2.9 × 10^6/g, heterotrophic bacteria 3.1 × 10³/g, heat-resistant bacteria 2.1 × 10³/g Pseudomonas aeruginosa 23/g. That for beans was 6.3 × 10²/g, psychrophile 34/g, heterotroph 1.7 × 10²/g. That for sesames was 1.4 × 10^5/g, coliform 350/g, psychrophile 7.4 × 10⁴/g, heterotroph 5.8 × 10⁴/g, Pseud. aeruginosa 2.3 × 10³/g. heat-resistant bacteria 150/g. That for potatoes was 2.0 × 10^7/g, coliform 5.0 × 10⁴/g, psychrophile 1.8 × 10^7/g, heterotroph 1.4 × 10^7/g, heatresistant bacteria 3.3 × 10¹/g, Staphylococcus 2.7 × 10^5/g, fecal streptococcus 4.5 × 10³/g, Pseud. aeruginosa 7.0 × 10³/g. That for mushrooms was 1.2 × 10^8/g, psychrophile 9.4 × 10^7/g, heterotroph 1.0 × 10^9/g, heat-resistant bacteria 1.6 × 10^5/g, Pseud. aeruginosa 1.3 × 10³/g. That for vegetables was 5.9 × 10^(11)/g, coliform 1.8 × 10^6/g, psychrophile 1.1 × 10²/g, heterotroph 8.4 × 10^(11)/g, heatresistant bacteria 7.6 × 10^6/g, Staphylococcus 1.1 × 10^7/g, fecal streptococcus l.1 × 10⁴/g, Pseud. aeruginosa 5.2 × 10⁴/g. That for nuts 3.9 × 10⁴/g, coliform 3.9 × 10³/g, psychrophile 4.0 × 10^8/g, heterotroph 3.2 × 10^8/g, heat-resistant bacteria 400/g. In commercial grains and beans, SPC, psychrophile, heterotroph and heat-resistant bacteria stored at 10℃, 20℃, 30℃ were constant. Staphylococcus, coliform, Pseud. aeruginosa were decreased a little in grains, but were not detected in beans. In mushrooms, all indicator organisms were increased as time goes on and were increased rapidly at 20. In sesames, coliform was not detected at all temperature. psychrophile was increased for 7 days, the otners were constant. In potatoes, SPC, psychrophile, heat-resistant bacteria, heterotroph had a tendency to increase and the others were constant. In vegetables, indicator organisms were had a tendency to increase, psychrophile, heterotroph were rapidly increased after 7 days. In nuts, SPC, coliform, psychrophile, heterotroph, heat-resistant bacteria, Pseud. aeruginosa were constant, staphylococcus and fecal streptococcus were not detected.

The average number of total viable counts for the commercial pork tested was 19/g, coliform 1.8/g, psychrophilic bacteria 15/g, heterotrophic bacteria 12/g, fecal streptococcus 6.2/100 g, Pseudomonas aeruginosa 13/100 g and none of heat-resistant bacteria and Staphylococcus was detected. That for the commercial beef tested was 130/g, coliform 5.2/g, psychrophile 140/g, heterotroph 28/g, Staphylococcus 1.2/g, fecal streptococcus 9.5/100 g, Pseud. aeruginosa 1.9/100 g and heat-resistant bacteria was not detected. That for the commercial chicken tested was 8800/g, coliform 53/g, psychrophile 4600/g, heterotroph 4700/g, fecal streptococcus 9.9/100 g, Pseud. aeruginosa 2.5/100 g. That for milk was 4700/ml, psychrophile 120/ml, heterotroph 420/ml and the others were not detected. That for the commercial cheese was 3.2/g, psychrophile 2.3/g, heterotroph 1.6/g, Staphylococcus 1/g, fecal streptococcus 9.1/g. That for fermented milk was 10^7/ml, heatresistant bacteria 10^6/ml, fecal streptococcus 2400/100 ml, lactobacillus 3.2 × 10^(15)/ml, in accordance with lactic acid bacteria and the others were not detected. There was not detected any indicator organisms from ham, sausage, butter, eggs and quails in the commercial fooods tested. SPC, coliform, psychrophile and heterotroph in commercial meats stored at 10℃ were increased rapidly as time goes on but heat-resistant bacteria, staphylococcus, fecal streptococcus and Pseud. aeruginosa were constant. At 20℃, SPC, coliform, psychrophile, heterotroph and fecal streptococcus were the highest at 7 days and heat-resistant bacteria, staphylococcus and Pseud. aeruginosa were increased a little. At 30℃, all indicators were increased rapidly for 3 and 7 days and then decreased rapidly. All indicator organisms were increased at the level of 10/g for 14 days in meat products stored at 10℃, but SPC, psychrophile and heterotroph in meat products stored at 20℃ were increased at the level of 10^5/g. It showed that the indicators in meat products stored at 30℃ had a tendency to increase at the level of l0₂/g relative to those stored at 20℃. SPC, psychrophile and heterotroph in milk stored at 10 increased up to the level of 10₄/ml, but coliform, staphylococcus, fecal streptococcus and Pseud. aeruginosa were not detected. As stored at 20℃ and 30℃, they were increased rapidly for 1 or 3 days and then constant for a long time.

This study analyzed the status of climate-change indicator plants native to the main islands of the Korean peninsula, while elucidating their distribution characteristics. Information on flora from over 129 island locations, comprising more than 100 species of native plants, was collected, compiled into a database, and utilized as raw data. The distribution of 193 climate-change indicator plants was confirmed. The distribution area of broadleaf evergreen trees and ferns, including Mallotus japonicus and Cyrtomium falcatum, was relatively wide. In contrast, the distribution of common northern plants such as Corydalis turtschaninovii and Malus baccata was limited. If global warming persists, northern plant distribution is expected to decrease rapidly in the Korean Peninsula island region, while the northern limit line of the southern plants is expected to migrate further northward. During this process, it is likely that the plant congregation structure and species diversity within the island region will change dynamically. In this study, comparative analyses between species and regions were conducted by assessing the relative frequency of their occurrence, and six types of botanical geographic distribution patterns were noted.

Temporal and spatial variations in surface ozone concentrations in Busan were investigated by using observation data from urban air quality sites during 2001-2016. The annual ozone concentrations showed a significant increasing trend of +0.40 ppb yr-1 in this period, with a more rapid increase of +0.81 ppb yr-1 since 2010. For the monthly analysis, the increase in ozone concentration was the greatest in August (+0.68 ppb yr-1). These ozone trends were due mainly to rising temperature (+0.05℃ yr-1) and weak decreasing precipitation (－6.42 mm yr-1). However, the extreme weather events (heat wave, localized heavy rain, etc.) lead to an increase in short-term variability of ozone since 2010. The relatively low ozone concentrations in the downtown area were caused by high NOx emissions from mobile sources. The increases in ozone concentrations were observed at most of the air quality monitoring sites due to the reductions in anthropogenic emissions of NOx during 2001-2015. However, in the southern coastal area, lower rates of increase in ozone concentrations were observed by –0.10~0.25 ppb yr-1 due to the significant NOx emitted by ships in the Busan port and Busan new port.

본 연구에서는 3차원 이산 균열망 수치모형을 이용하여 균열망을 구성하는 균열요소의 길이분포가 유체 흐름 특성이 미치는 영향에 대해 수치적으 로 분석하였다. 균열요소의 길이분포의 생성을 위해 절단멱분포법칙을 적용하였으며, 지수 β₁을 1.0에서부터 6.0까지 변화시키면서 유체 흐름 모의를 수행하였다. 모의결과 지수 β₁이 증가함에 따라 균열요소들의 길이분포는 점차적으로 작아지며, 이로 인해 균열망의 투수성에 영향을 미치는 균열요소들 간의 연결성은 취약해지는 것으로 나타났다. 각각의 지수 β₁에 대해 균열요소 각각에서 계산된 유량분포를 분석하였을 때 β₁= 1.0에 서의 평균유량이   6.0에 비해 약 447배 크게 산정되었으며, 균열망의 유출경계에서 계산된 유량의 경우 β₁일 때가 6.0에 비해 약 6,440배 크게 산정되었다.

To investigate the distribution characteristics of grain size and organic matter of surface sediments from the Nakdong-Goryeong Mid-watershed, surface sediments were collected and analyzed. The samples were collected from six sited at four different times between May 2013 and May 2014. The were analyzed for grain size, water content, ignition loss, chemical oxygen demand, total organic carbon and total nitrogen. The surface sediments were mainly composed of medium sand (mean 44.7%) and coarse sand (mean 32.8%) and became coarser in May 2014. Fine sediments at the site NG-2 were poorly sorted and positively skewed, and occur in a tributary environment that is relatively low-energy compared with the other sites. The water content at the studied sites (15.3 ~ 34.9%) averaged 20.25%, and ignition loss (0.4 ~ 5.8%) and total nitrogen (274 ~ 2493 mg/kg) averaged 1.33% and, 696 mg/kg, respectively. These values indicated that the sediments were not seriously contaminated when compared with the sediment pollution evaluation standard of the National Institute of Environmental Research. The chemical oxygen demand (mean 0.17%) was at the non-polluted level compared with United States Environmental Protection Agency sediment quality standards. The total organic carbon (mean 0.18%) at all sites except site NG-2 (lowest effect level) was the no effect level of the Ontario sediment quality guidelines. The COD/IL (0.02 ~ 0.20) and C/N (0.73 ~ 6.76) were less than 1 and 10, respectively. Organic matter in the study area produced naturally from aquatic organisms. Results of principal component analysis showed that fine sediments (very fine sand and silt) were significantly affected by organic matters (ignition loss, chemical oxygen demand, total organic carbon and total nitrogen). In addition, the highest organic matters content in the study area occurred at the site with the finest sediments (NG-2).

Regional climate simulations for the CORDEX East Asia domain were conducted between 1981 and 2100 using five models to project future climate change based on RCP2.6, 4.5, 6.0, and 8.5 scenarios. By using the ensemble mean of five model results, future changes in climate zones and four extreme temperature events of South Korea were investigated according to Köppen-Trewartha’s classification criteria. The four temporal periods of historical (1981-2005), early future (2021-2040), middle future (2041-2070), and late future (2071-2100) were defined to examine future changes. The analysis domain was divided into 230 administrative districts of South Korea. In historical (1981-2005) period, the subtropical zones are only dominant in the southern coastal regions and Jeju island, while those tend to expand in the future periods. Depending on the RCP scenarios, the more radiative forcing results in the larger subtropical zone over South Korea in the future. The expansion of the subtropical zone in metropolitan areas is more evident than that in rural areas. In addition, the enlargement of the subtropical zone in coastal regions is more prominent than that of in inland regions. Particularly, the subtropical climate zone for the late future period of RCP8.5 scenario is significantly dominant in most South Korea. All scenarios show that cold related extreme temperature events are expected to decrease and hot related extreme temperature events to increase in late future. This study can be utilized by administrative districts for the strategic plan of responses to future climate change.

We conducted a total of 28 surveys from March to October 2016 in Gayasan National Park, to identify threatened plants for climate change, as well as for the effective management of biological organisms and resources against climate changes in Korea. Regarding threatened plants for climate change, we identified a total of 39 taxa, with 11 northern, 2 southern, and 26 taxa of concern. Among these taxa, 33 were identified as wild species. The species threatened by climate change located in the subalpine regions of Gayasan National Park were Abies holophylla Maxim., Abies koreana Wilson, Pinus koraiensis Siebold & Zucc., Betula ermanii Cham., Berberis amurensis Rupr., Rhododendron tschonoskii Maxim., Vaccinium hirtum var. koreanum (Nakai) Kitam., Primula modesta var. hannasanensis T.Yamaz., Trientalis europaea var. arctica (Fisch.) Ledeb., Thymus quinquecostatus Celak., Parasenecio firmus (Kom.) Y.L.Chen, and Lilium cernuum Kom. These species are expected to be particularly vulnerable to the effects of global warming, since they were confirmed to have a very narrow vertical distribution range. Moreover, although the following species are not included in the list of plants threatened by climate change, it is assumed that the endemic species that grow at the summit, and Grade V floristics special plants, such as Pedicularis hallaisanensis Hurus., Allium thunbergii var. deltoides (S.O.Yu, S.Lee & W.Lee) H.J.Choi & B.U.Oh, Heloniopsis tubiflora Fuse, N.S.Lee & M.N. Tamura, Aletris glabra Bureau & Franch, and Gymnadenia cucullata (L.) Rich., will also be extremely vulnerable to climate change. Therefore, we believe that measures for the conservation of these species are urgently needed, and also that the definition of species threatened by climate change should be broadened to include more objective and valid taxa through the long-term monitoring of species distributed around the summit area.

To certificate change in the geochemical characteristics of surface sediments in the main stream of the Nakdong River, surface sediments from 12 sampling sites during the first and second half year (total 24 sampling sites) were collected and analyzed for grain size, ignition loss, total organic carbon and heavy metal content. Surface sediments mainly composed of sand (coarse and medium sand) and fining changed from the first half to the second half of the year. Ignition loss, total organic carbon and heavy metals content increased in the second half of the year. Some heavy metals (Zn, Ni and Cu) were found to be at the lowest effect levels according to Ontario sediment quality guidelines. Additionally, most heavy metals were found to be at the non polluted level and level I according to USEPA sediment quality standards and National Institute of Environmental Research sediment pollution evaluation standard, respectively. The enrichment factor (< 1) and index of geoaccmulation (< 0) were non polluted in the study area. The correlation analysis results showed that ignition loss, total organic carbon and heavy metal content were highly correlated with grain size. Regarding changes in geochemical characteristics of surface sediments in the study area, grain size fine and organic matter and heavy metal content increased in the second half year. Nonetheless these results indicated pollution levels that did not adversely affect the benthos.