In this study, we investigated the Indoor and Outdoor concentrations of PM10 in Y area, Jeollanam-do. We conducted personal exposure concentration estimates, and Exposure and Risk Assessments using the Time-weighted Average Model. The concentration of Indoor PM10 was 49.38 μg/m3 and that of Outdoor PM10 was 48.02 μg/m3, with the Indoor/ Outdoor Ratio value being 1 or more, and it was found that there was an indoor source of pollution. The Indoor/Outdoor Cr ratio value was 1 or more, and the source of Cr was confirmed to be indoor. Based on our analysis, there was a positive correlation between heavy metals Ni, Cr, and Mn (p<0.05). Using the Time-Weighted Average model, we determined the PM10 personal exposure concentration to be 49.36 μg/m3 and confirmed the feasibility of this model in utilizing the PM10 personal exposure concentrations. In this study, the findings are likely to provide useful data that can be used to determine the concentration of indoor pollutants that are not easy to survey. However, to accurately evaluate indoor air quality, more factors need to be considered and evaluated.

We conducted a field survey from 2018 to 2020 to analyze the spatial distribution of phytoplankton communities at 13 stations in the East Sea. The diatom Chaetoceros curvisetus appeared as the dominant species in winter, and small flagellates less than 20 μm prevailed in all seasons except winter. The seasonal average range of the micro (>20 μm), nano (20 μm≥Chl-a>3 μm), and picophytoplankton (≤3 μm) was 20.6-26.2%, 27.1-35.9%, and 40.8-49.0%, respectively. The composition ratio of nano and picophytoplankton was high at the surface mixed layer from spring to autumn when the water columns were strongly stratified. Especially, the stability of the water mass was increased when the summer surface water temperature was higher than that of the previous year. As a result, the nutrient inflow from the lower layer to the surface was reduced as the ocean stratification layer was strengthened. Therefore, the composition ratio of nano and picophytoplankton was the highest at 77.9% at the surface mixed layer. In conclusion, the structure of the phytoplankton community in the East Sea has been miniaturized, which is expected to form a complex microbial food web structure and lower the carbon transfer rate to the upper consumer stage.

Volatile organic compounds (VOCs) are chemicals to which humans are exposed frequently via various mediums, including vehicle emissions that contain fine dust and heavy metals, use of organic solvent building materials, furniture, and smoking. Exposure to high concentrations of VOCs may result in loss of consciousness, paralysis, convulsions, and, in the most severe cases, death. Therefore, the present study investigated the indoor and outdoor concentrations of total volatile organic compounds (TVOC) and five types of VOCs (benzene, toluene, styrene, m,p-xylene, and o-xylene) in apartments, a representative residential environment accounting for ~55% of the housing in the Seoul metropolitan area. The research was conducted over four seasons from May 2020 to February 2021, and the levels of VOC concentrations were analyzed by classifying them by season, weekday/weekend, and indoor/outdoor locations. The seasonal trend in VOC concentrations showed that TVOC concentration was highest in summer, with values of 1630.93 ± 1184.10 μg/m3 and 1610.36 ± 1363.43 μg/m3 for indoor and outdoor environments, respectively. The seasonal trends of the concentrations of the five types of VOCs showed that concentrations of benzene and toluene were highest in spring, the concentrations of m,p-xylene and o-xylene were highest in summer, and the concentration of styrene was highest in winter, irrespective of spatial characteristics such as indoor/outdoor environments. In all four seasons, the indoor concentrations were higher than the outdoor concentrations. These results reveal the spatial and temporal distribution characteristics of the VOCs and so can serve as useful basic data for managing indoor and outdoor levels of VOCs.

Total of 325 estuaries in Korea were surveyed to analyze the effect of presence of sluice gate on the estuary environment and fish community from 2016 to 2018. Fish community in closed and open estuaries showed differences generally, and the relative abundance (RA) of primary freshwater species in the closed and migratory species in the open estuaries were high. The result of classifying species by habitat characteristics in closed and open estuaries showed similar tendencies at the estuaries of south sea and west sea. The relative abundances of primary freshwater species in the closed estuaries at the estuaries of south sea and west sea were the highest, but estuarine and migratory species were high in both closed and open estuaries at the estuaries of east sea. Primary freshwater species showed higher abundances in the closed estuaries with reduced salinity due to blocking of seawater since they are not resistant to salt. However, primary freshwater species in open estuaries at east sea was higher than that of the closed estuaries, which is considered to be the result of reflecting the characteristics (tide, sand bar, etc.) of the east sea. Korea Estuary Fish Assessment Index (KEFAI) was showed to be higher at open estuaries than closed in all sea areas (T-test, P<0.001), the highest KEFAI was observed in closed estuaries at south sea, and open estuaries in east sea. Fish community of closed and open estuaries in each sea areas showed statistically significant differences (PERMANOVA, East, Pseudo-F=3.0198, P=0.002; South, Pseudo-F=22.00, P=0.001; West, Pseudo-F=14.067, P=0.001). Fish assemblage similarity by sea areas showed a significant differences on fish community in closed and open estuaries at east sea, south sea, and west sea (SIMPER, Group dissimilarity, 85.85%, 88.36%, and 88.05%). This study provided information on the characteristics and distribution of fish community according to the types of estuaries. The results of this study can be used as a reference for establishing appropriate management plans according to the sea areas and type in the management and restoration of estuaries for future.

본 연구는 무분별한 섬 개발과 섬의 특성을 고려하지 않은 사업 등 섬 경관 특성 파악의 필요성이 증대됨과 동시에 기존 경관 연구의 한계를 보완하는 방법으로서 빅데이터 분석을 활용하고자 하였다. 따라서 본 연구는 섬 경관은 관광 동기의 중요 지표인 고유한 섬의 경관 특성을 파악함으로써 이를 고려한 계획 및 관리방안의 기초자료 제시를 목적으로 하였다. 연구의 범위는 가장 많은 섬을 보유하고 있는 전라남·북도의 섬 중 국내·외에서 인정받은 섬 중 빅데이터 분석을 하기에 용이한 데이터를 보유하고 있는 청산도, 선유도, 보길도, 박지·반월도로 한정하였다. 수집된 데이터는 사진 및 텍스트 데이터로서 이를 각각의 경관 특성을 파악하고 관계를 분석하기 위하여 형식미학적·심리적 경관특성으로 분류하여 결과를 도출하였다. 형식미학적 경관 특성은 사진 데이터를 토대로 경관파악모델 및 색채, 색채 이미지 형용사 분석을 실시하여 각 섬이 보유한 경관구성요소와 특성을 파악하였으며, 심리적 경관특성은 텍스트 데이터를 활용하여 빈도분석, N-gram, 네트워크 분석, 감성분석 등을 실시하여 경관 대상과 행태, 이미지 등을 파악하였다. 위와 같은 결과를 종합하여 섬 경관이 대중에게 어떻게 활용되고 있는지 의미를 파악하였으며 섬 연구에서 수행하는 데 발생되는 시간적·비용적 측면의 한계점뿐만 아니라 계절, 시계열 등 시간적 특성을 파악할 수 있다는 점에서 기존의 연구를 보완할 수 있었다. 또한, 각 섬의 경관 특성을 고려하여 추후 섬 발전 방향을 더욱 구체화시킬 수 있는 장치가 될 수 있다는 시사점을 제시하였다.

In this study, the appropriate unit cost in grassland establishment was redeveloped by the grassland establishment method and work criteria. The grassland establishment method was divided into tillage establishment (all logging) and no-tillage establishment (all logging and partial logging). The price for the work criteria by the establishment method was presented for each permission/authorization and establishment work. In permission/authorization for grassland establishment, the cost of each work criteria was of environmental impact (small scale environmental impact) assessment, disaster impact assessment, cadastral serving fee, forest survey, and connection fee for control of mountainous districts. In establishment was of logging, cleaning/gruffing, plowing/soil preparation, seeding, fertilization, livestock manure compost, seed, herbicide, labor cost (fertilizer, seed and herbicide), soil consolidation, cattle trail, and fence. The unit cost of grassland establishment was KRW 115,894,212 for the tillage establishment, and KRW 110,281,572 and KRW 106,680,122 for the all and partial logging of the no-tillage establishment, respectively. The current study redeveloped the establishment method, work criteria, and estimation of the unit cost of grassland establishment. It can be usefully used to carry out government projects to support related to establishment and maintenance of grassland.

In this study, trends in research methods and topics of seabird and marine fish migration were examined. Based on the framework of existing animal migration studies, future research directions were proposed in relation to the migration of seabirds and fish. In terms of research methodology, with the development of science and technology, tracking techniques using radio telemetry, acoustic telemetry, RFID (radiofrequency identification), satellite tracking, and geolocators are widely used to study seabird and fish migration. Research is also conducted indirectly through a population survey and the analysis of substances in the body. Research contents are largely classified into extrinsic factors that affect migration (such as environmental variables and interspecific competition), intrinsic factors such as hormones, anthropogenic activities including fishery and offshore wind farm, and the effect of global climate change. In future studies, physiological factors that influence or cause migration and dispersal should be identified concerning intrinsic factors. For the analysis of migration ability, it is necessary to study effects of changes in the magnetic field on the migration ability of seabirds and fish, interspecific differences in spatiotemporal migration ability, and factors that influence the migration success rate. Regarding extrinsic factors, research studies on effects of anthropogenic disturbances such as fishery and offshore wind farm and global climate change on the migration and dispersal patterns of marine animals are needed. Finally, integrated studies on the migration of seabirds and fish directly or indirectly affecting each other in various ecological aspects are required.

This study was conducted to investigate the effects of summer green manure crops as an alternative for imported expeller cake fertilizer on environment-friendly lettuce production. Sunnhemp, soybean, sudangrass, and sorghum, as summer green manure crops, were evaluated under the condition of a plastic film house. In the amount of nitrogen supplied through cultivation of green manure crops, soybean plot, which supplied 187 kg ha-1, was the highest, followed by sorghum plot, 156 kg ha-1. Since all green manure plots supplied more nitrogen than that required by soil testing, it was possible to replace the nitrogen supply of expeller cake fertilizer with the amount of nitrogen produced by green manures for autumn lettuce cultivation. N nutrient balances in sunnhemp, sudangrass, soybean, and sorghum plots were 13 kg ha-1, 28 kg ha-1, 30 kg ha-1, and 38 kg ha-1, respectively. The initial yield and total yield of lettuce showed no significant difference in green manure plots compared to the expeller cake plot, but . It was thought that all green manure crops could be substituted for expeller cake fertilizer used as nitrogen fertilizer, but it would be necessary to adjust the cultivation period and reduction point according to the type of green manure in order to maintain the C/N ratio, nitrogen supply, and nitrogen balance suitable for lettuce production.

본 연구는 직무 자원, 직무 요구, 개인 자원이 공직자들의 조직 몰입에 미치는 영향을 개인 수준과 조직 수준에서 분석하는 데 그 목적이 있다. 이를 위해 63개 기관에서 근무하는 공무원 4,339명으로부터 자료 를 수집한 4차 공직생활실태조사 자료를 활용하였다. 가설을 검증하기 위해 위계적 선형 모형을 활용하였 으며, 분석 결과, 공직자들의 조직 몰입은 조직에 따라 차이가 존재하는 것으로 나타났다. 구체적으로 변 화 지향성, 목표 명확성, 공공 봉사 동기, 공직 가치가 높을수록, 역할 모호성은 낮을수록 조직 몰입이 높 았고, 광역 자치 단체 공무원이 중앙 행정 기관 공무원보다, 남자 공무원이 여자 공무원보다, 대학원 졸업 이상의 교육 수준을 가진 공무원이 대졸 공무원들보다 조직 몰입이 높았다. 연구결과를 바탕으로 이론적 시사점을 논의하였고, 공직자들의 조직 몰입을 높이기 위한 실천적 방안을 제시하였다.

본 논문의 목적은 건축물을 드론으로 계측하여 드론의 비행 및 촬영 변수에 따른 계측 정확도를 분석하는 것이다. 드론의 비 행 및 촬영 변수는 비행고도 3가지(50m, 60m, 70m), 중복도 4가지(60%/60%, 60%/80%, 80%/60%, 80%/80%), 카메라 각도 2가지(45°, 90°), 속도 2가지(2m/s, 최고속도)이며, 총 48번을 계측하였다. 드론으로 계측하여 얻은 3D 데이터와 실제 건축물의 길이를 비교하였으 며, 드론의 비행 속도가 느릴수록 정확도가 높게 나타났다.

In this study, we learned about the effects of indoor radon concentration reduction associated with the operation of a mechanical ventilation system at an apartment house. The experimental parameters were mainly the indoor radon level and air change rate, which were controlled by the amount of emissions released and fan motor speed. Even at the high level of radon diffused in an apartment house, indoor radon concentrations converged to the Korean national guideline level within 3 to 4 hours when the air was ventilated at 0.5 ACH and 0.7 ACH. In the case of 0.3 ACH, however, where the degree of ventilation was insufficient compared to the legal air change rate, the high concentration indoor radon could not be sufficiently removed even if the mechanical ventilation system was operated for more than 14 hours continuously. When the indoor radon level was high, the reduction rate was 34.3% for 0.3 ACH, 70.4% for 0.5 ACH, and 69.7% for 0.7 ACH at 6 hours-operation, while at the medium-level, indoor radon can be reduced by 46.2% (0.3 ACH) to 73.2% (0.7 ACH). Depending on the indoor concentration range, it may be required to secure a ventilation rate of 0.5 ACH or more at all times. In addition, in apartment houses with excellent airtight performance, even if indoor radon is at a level similar to the national guideline, it is difficult to expect a reduction in the concentration due to natural decay. Therefore, it is desirable to lower the indoor concentrations as much as possible.

An estuary is an area where a freshwater river or stream meets the ocean. Even before the importance of the value of estuaries was recognized, the estuary was lost because of large-scale conversion by draining, filling, damming, and dredging. In South Korea, 643 estuaries are located, and the total area is 3,248,300 ha, accounting for 32.5% of the total area of South Korea. Over 35% of Korean estuaries are closed estuaries which are only temporally connected with the sea, either permanently or periodically. Since 2008, in order to preserve the estuary ecosystem and solve major issues in the estuary by accumulating knowledge about the estuarine ecosystem, the Ministry of Environment of Republic of Korea has been conducting the “Estuarine Ecosystem Monitoring and Assessment Project”. At 668 sites of 325 estuaries, epilithic diatom, benthic macroinvertebrate, fish, and vegetation are investigated, and the habitat condition of each site is evaluated using the newly developed biotic index. More than 100 researchers annually record 2,097 species of estuaries according to the standardized survey guidelines over the past 14 years and provide strictly managed data necessary for establishing estuaries conservation policies. As a result of bibliometric analysis of 1,195 research articles related to the monitoring and assessment of the estuarine ecosystem, research on pollutants such as heavy metals and sediment control have recently been conducted. “Estuarine Ecosystem Monitoring and Assessment Project” is an ecological monitoring type of long-term mandated monitoring that is usually focused on identifying trends. Although it is difficult to identify the mechanism influencing a change in an ecosystem through long-term mandated monitoring, providing empirical data for supporting evidence-based policy, decision-making, and the management of ecosystems. In order to increase the efficiency of the project, research to investigate the relationship between sediments and pollutants and organisms can be conducted at specific estuaries or sites to compensate for the shortcomings of mandatory monitoring.

This paper aims to propose a new systematic approach to analyze the factor productivity and to investigate those characteristics of factor productivity in operational and managerial perspectives. The Cobb-Douglas production function is adopted to estimate the labor and capital productivity. In estimating those productivities the data of The Research on the Actual Condition of Coastal Fisheries (RACF), especially those of Jeon-Nam Province are used. The statistical analysis of RACF data shows that the characteristics are a little bit different between labor and capital of the operational equipment in the coastal fisheries. The Cobb-Douglas type production function is useful in estimating the factor productivity, especially in case of ‘coastal Stow-net fishery’ even though the limited data is used. However, in case of ‘trap fishery,’ the Cobb-Douglas production function appears to have some limitations in estimation. This implies that estimating the factor productivities in fisheries employing broad perspectives and various methods are needed.

Laos People’s Democratic Republic (Laos) is a country selected by Korea’s priority foreign policy – New Southern Policy. It is also one of Korea’s 24 priority partner countries. The objective of this study was to understand the current status of rice industry and recommendations for improving rice productivity in Laos based on “Agriculture Development Strategy to 2025 and Vision to the Year 2030” published by the Lao government. In Laos, major crops are rice, vegetables, maize, coffee, cassava, sugar cane, and others. Laos achieved rice self-sufficiency in 1999. Its rice production reached up to 3,580,000 tons in 2018. It aims to harvest a total of 5 million tons of paddy rice with a target yield of approx. 1.5 million tons in 2025. Rice consumption per capita totals 160 kg/year in Laos, the highest in the world. The national nutrient program sets its targets as follows: of 2,600 kcal, a recommended daily calorie intake for adults, it aims to lower rice and starch, while increasing calories from meat, vegetables, fat, and so on. This shows that the rice policy is formulated with consideration of improving health of people in Laos as well as boosting rice exports. Based on the agricultural policy and strategy of Laos, it is viewed that the rice industry in Laos can advance further and produce results only when rice industry is linked to the following areas: economic development, farm size expansion, higher productivity through novel varieties and cultivation technologies, scaling-up of agricultural mechanization, greater efficiency in processing, and infrastructure expansions such as roads and reservoirs. If an ODA (Official Development Assistance) project takes a tailored approach considering its actor-specific characters and tasks, it is believed that the project can contribute to the goal of securing sustainability for the rice industry.

과거부터 해상은 육상의 도로와 같이 선박이 통항할 수 있는 항로가 지정되 어 있거나 선박 통항의 자유가 보장되는 공간이었다. 하지만, 자원 개발이나 안 보 등의 여러 이유로 연안국의 관할권 확대가 이루어지면서 선박 통항의 자유 가 보장되는 수역인 공해가 점점 축소됨으로써 선박 통항의 제한이 이루어질 수 있다는 우려가 커졌다. 그 결과 연안국의 주권이 미치는 수역에서도 항해 의 자유는 보장할 수 있도록 무해통항권과 같은 제도가 마련되었다. 무해통항권이란 말 그대로 선박이 연안국의 관할권 수역을 통항함에 있어 연안국에 무 해할 경우는 선박 통항을 보장해 주는 것을 의미한다. 그런데, 국내 연안에 설 정되어 있는 유조선통항금지해역은 해당 해역을 통항하는 유조선의 유무해성 에 상관없이 통항을 금지하고 있어 국제법인 유엔해양법협약에 저촉될 수 있 다. 이에 일방적으로 유조선의 통항을 금지하기 보다는 유조선의 주의항해 및 연안국의 적극적인 관리가 이루어질 수 있도록 유조선통항주의해역으로의 변 경이 필요하다고 사료된다. 그렇게 함으로써 유조선통항금지해역의 입법 취지 의 달성과 국제법의 저촉 문제도 해결될 수 있을 것이다.