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Spatio-temporal Characteristics of Macrobenthic Community in the Coastal area of South Korea (우리나라 연안 대형저서동물 시·공간 군집 특성 분석)

  • KIM, Young-Jun;IM, Jung-Ho;CHO, Chun-Ok;RYU, Jong-Seong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.3
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    • pp.100-117
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    • 2022
  • This study examines the spatio-temporal characteristics of the macrobenthic community in the coastal areas of South Korea for the past six years(2015-2020). The relationship between the number of individuals of macrobenthic species and the benthic environments were investigated using data collected at a total of 154 stations located in the West (70), the South (61), and the East Seas (23), except for the Jeju Sea. We examined the benthic environmental characteristics such as water depth, sediment, grain size, ignition loss, and total organic carbon. A total of 1,614 macrobenthic species were found in the coastal area, with a mean density of 0.62 ind./m2 by station. The mean density was relatively high in the spring and summer seasons (May to August) with more than 450 species. The most dominant species belong to Polychaetes and the top five of them accounted for more than 20% of the total number of populations. The top five species were Heteromastus filiformis, Scoletoma longifolia, Sigambra tentaculata, Sternaspis scutata, and Notomastus latericeus. Cluster analysis was performed on the top five dominant species. The stations were clustered into three groups with similar locations on the West, South, and East Sea. Cluster 1 and 3 represent Heteromastus filiformis (44% each), but cluster 2 represents Scoletoma longifolia (66%). Each cluster has different benthic environmental characteristics, especially in the sediment's sand (31.0%, 51.9%) and clay (15.9%, 9.7%) contents.

Mapping the Research Landscape of Wastewater Treatment Wetlands: A Bibliometric Analysis and Comprehensive Review (폐수 처리 위한 습지의 연구 환경 매핑: 서지학적 분석 및 종합 검토)

  • C. C. Vispo;N. J. D. G. Reyes;H. S. Choi;M.S. Jeon;L. H. Kim
    • Journal of Wetlands Research
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    • v.25 no.2
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    • pp.145-158
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    • 2023
  • Constructed wetlands (CWs) are effective technologies for urban wastewater management, utilizing natural physico-chemical and biological processes to remove pollutants. This study employed a bibliometric analysis approach to investigate the progress and future research trends in the field of CWs. A comprehensive review of 100 most-recently published and open-access articles was performed to analyze the performance of CWs in treating wastewater. Spain, China, Italy, and the United States were among the most productive countries in terms of the number of published papers. The most frequently used keywords in publications include water quality (n=19), phytoremediation (n=13), stormwater (n=11), and phosphorus (n=11), suggesting that the efficiency of CWs in improving water quality and removal of nutrients were widely investigated. Among the different types of CWs reviewed, hybrid CWs exhibited the highest removal efficiencies for BOD (88.67%) and TSS (95.67%), whereas VSSF, and HSSF systems also showed high TSS removal efficiencies (83.25%, and 78.83% respectively). VSSF wetland displayed the highest COD removal efficiency (71.82%). Generally, physical processes (e.g., sedimentation, filtration, adsorption) and biological mechanisms (i.e., biodegradation) contributed to the high removal efficiency of TSS, BOD, and COD in CW systems. The hybrid CW system demonstrated highest TN removal efficiency (60.78%) by integrating multiple treatment processes, including aerobic and anaerobic conditions, various vegetation types, and different media configurations, which enhanced microbial activity and allowed for comprehensive nitrogen compound removal. The FWS system showed the highest TP removal efficiency (54.50%) due to combined process of settling sediment-bound phosphorus and plant uptake. Phragmites, Cyperus, Iris, and Typha were commonly used in CWs due to their superior phytoremediation capabilities. The study emphasized the potential of CWs as sustainable alternatives for wastewater management, particularly in urban areas.

Single Person Household and Urban Policy in Seoul (도시에서 혼자 사는 것의 의미: 1인가구 현황 및 도시정책 수요)

  • Miree BYUN
    • Korean Journal of Culture and Social Issue
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    • v.21 no.3
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    • pp.551-573
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    • 2015
  • The rise of single living has been one of the most important demographic shifts of recent decades. The solo household is a little less than 40% in Europe areas and that of Tokyo is over 45%. Being impacted this figure, the formation of single economy is the key word in World Economic Forum(WEF) 2008. Seoul' single household is increasing rapidly. Between 2000 and 2005, the growth of single person is around 34%, the population of single person reached 700,000 people. Now 20% of total household in Seoul is Single household. Living alone or solo living is not exceptional or special in Seoul Metropolitan City. The rise in single living will create pressures towards poverty and inequality and so on. Seoul should develop and prepare the urban policy for single household. We figured out the four key trends which composed of single household in Seoul. Four types of single person are like below : Gold Mr and Miss, Reserved labor forces, depressed single and silver generation. Gold group is amonst people aged 30 and 40 who is working in the area of white collar and professional. They are usually elective single person household who have chosen solo living. Reserved labor forces group is usually among 20s people who have not get the regular hob. For this group, job acquiring is the most important issue. Depressed single person household group is among people aged late 30s and 40s. Its group is the result from the broken family. The silver group is among aged over 65 that is the main issue of the aged society. In this research, we stressed that people living alone can be split into two types - elective single person households who have chosen single living, and forced single person household who have been constrained to this lifestyle by circumstances. Except gold group, the rest of the group is the forced single household who are faced to poverty. The monthly income of single person household is almost under 2 million won. Single person household is usually working in the blue collar job and service area. So, except gold group that is the smallest part of single person household, almost single person is not the target of private market, but the object of public policy.

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Management Planning of Wind Corridor based on Mountain for Improving Urban Climate Environment - A Case Study of the Nakdong Jeongmaek - (도시환경개선을 위한 산림 기반 바람길 관리 계획 - 낙동정맥을 사례로 -)

  • Uk-Je SUNG;Jeong-Min SON;Jeong-Hee EUM;Jin-Kyu MIN
    • Journal of the Korean Association of Geographic Information Studies
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    • v.26 no.1
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    • pp.21-40
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    • 2023
  • This study analyzed the cold air characteristics of the Nakdong Jeongmaek, which is advantageous for the formation of cold air that can flow into the city, in order to suggest the wind ventilation corridor plans, which have recently been increasing interest as a way to improve the urban thermal environment. In addition, based on the watershed analysis, specific cold-air watershed areas were established and management plans were suggested to expand the cold air function of the Nakdong Jeongmaek. As a result of the analysis of cold air in the Nakdong Jeongaek, cold air was strongly generated in the northern forest of the Jeongamek, and flowed into nearby cities along the valley topography. On average, the speed of cold air was high in cities located to the east of the Jeongmaek, while the height of cold air layer was high in cities located to the west. By synthesizing these cold air characteristics and watershed analysis results, the cold-air watershed area was classified into 8 zones, And the plans were proposed to preserve and strengthen the temperature reduction of the Jeongmaek by designating the zones as 'Conservation area of Cold-air', 'Management area of Cold-air', and 'Intensive management area of Cold-air'. In addition, in order to verify the temperature reduction of cold air, the effect of night temperature reduction effect was compared with the cold air analysis using weather observation data. As a result, the temperature reduction of cold air was confirmed because the night temperature reduction was large at the observation station with strong cold air characteristics. This study is expected to be used as basic data in establishing a systematic preservation and management plan to expand the cold air function of the Nakdong Jeongmaek.

A Study on Space Creation and Management Plan according to Characteristics by Type in Each Small-Scale Biotope in Seoul - Base on the Amphibian Habitats - (서울시 소규모 생물서식공간 유형별 특성에 따른 조성 및 관리방안 연구 - 양서류 서식지를 중심으로 -)

  • Park, Ha-Ju;Han, Bong-Ho;Kim, Jong-Yup
    • Journal of the Korean Institute of Landscape Architecture
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    • v.52 no.2
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    • pp.110-126
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    • 2024
  • This study conducted a classification of small-scale biological habitats created in Seoul to analyze and synthesize location characteristics, habitat structure, biological habitat functions, and threat factors of representative sites, as well as derive creation and management problems according to the ecological characteristics. The aim was to suggest improvement measures and management items. Data collected through a field survey was used to categorize 39 locations, and 8 representative sites were selected by dividing them into location, water system, and size as classification criteria for typification. Due to the characteristics of each type, the site was created in an area where amphibian movement was disadvantageous due to low or disconnected connectivity with the hinterland forest, and the water supply was unstable in securing a constant flow and maintaining a constant water depth. The habitat structure has a small area, an artificial habitat structure that is unfavorable for amphibians, having the possibility of sediment inflow, and damage to the revetment area. The biological habitat function is a lack of wetland plants and the distribution of naturalized grasses, and threats include the establishment of hiking trails and decks in the surrounding area. Artificial disturbances occur adjacent to facilities. When creating habitats according to the characteristics of each type, it was necessary to review the possibility of an artificial water supply and introduce a water system with a continuous flow in order to connect the hinterland forest for amphibian movement and locate it in a place where water supply is possible. The habitat structure should be as large as possible, or several small-scale habitats should be connected to create a natural waterfront structure. In addition, additional wetland plants should be introduced to provide shelter for amphibians, and facilities such as walking paths should be installed in areas other than migration routes to prevent artificial disturbances. After construction, the management plan is to maintain various water depths for amphibians to inhabit and spawn, stabilize slopes due to sediment inflow, repair damage to revetments, and remove organic matter deposits to secure natural grasses and open water. Artificial management should be minimized. This study proposed improvement measures to improve the function of biological habitats through the analysis of problems with previously applied techniques, and based on this, in the future, small-scale biological habitat spaces suitable for the urban environment can be created for local governments that want to create small-scale biological habitat spaces, including Seoul City. It is significant in that it can provide management plans.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

Effect of Different Preservation Methods on Physicochemical Quality of Beef

  • Akter, H.;Akhter, S.;Rahman, S.M.E.;Rahman, M.M.;Hossain, M.M.;Ra, C.S.;Kim, Jai-Moung;Oh, Deog-Hwan
    • Journal of Food Hygiene and Safety
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    • v.24 no.3
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    • pp.217-225
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    • 2009
  • The study was conducted to evaluate the effect of drying, curing and freezing on the quality of beef. Three types of dried (without salt = $T_1$, with salt = $T_2$ and salt + spices = $T_3$); three types of cured (salt curing = $T_4$, sugar curing = $T_5$ and brine curing = $T_6$) and three types of frozen beef ($0^{\circ}C=T_7^{\circ}C$, $-10^{\circ}C=T_8$ and $-20^{\circ}C=T_9$) were analyzed at different time intervals up to the period of 180 d. Parameters studied were protein, fat, ash, color and cooking loss of beef. All the chemical constituents (protein, fat and ash) were decreased gradually up to 120 d. The decreasing trend was observed rapid after 120 d up to 180 d of preservation. Highest protein loss was found in $T_7$ (11.1 %) and the lowest protein loss was found in $T_6$ (3.85%) in 180 d preservation and significant (p < 0.01) differences were observed among the different preservation methods. Highest fat loss was observed in $T_6$ (7.62%) and the lowest fat loss was observed in $T_2$ (3.18%) and the differences were also significant (p < 0.05) among different methods during the experimental period. Spices dried beef showed a brighter color than others and cured beef showed brown color and the intensity of color was reduced gradually with the increasing of storage period. $T_9$ showed the lowest cooking loss among 3 treatments of frozen beef and the differences also significant (p < 0.01) up to 180 d. It might be stated that sugar curing ($T_5$) and spices drying ($T_3$) would be the useful technique of meat preservation in rural areas and freezing ($T_9$) would be used in large scale preservation at urban areas.

Effects of Air Pollution and Acid Precipitation on Soil pH and Distribution of Elements in Forest Ecosystem (대기오염(大氣汚染) 및 산성우(酸性雨)가 삼림생태계(森林生態系)의 토양산도(土壤酸度) 및 양료분포(養料分布)에 미치는 영향(影響))

  • Lee, Soo Wook;Min, Ill Sik
    • Journal of Korean Society of Forest Science
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    • v.78 no.1
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    • pp.11-25
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    • 1989
  • Four regions have been selected and surveyed to investigate the effects of air pollution and acid deposition on forest ecosystem. They were Seoul as urban region, Yeochon and Ulsan as industrialized region, and Kangwondo as uncontaminated region. Soil pH and the distribution of elements were analyzed in process of time for three years as well as by distance from pollution sources. In general, forest soils acidified in process of time from pollution sources to suburban areas. Hydrogen ion concentration in forest soils increased in 1988 as much as 60% of that in previous year. Average soil pH values in coniferous forest were 4.45 in Seoul, 4.54 in Yeochon, 4.81 in Ulsan, and 6.03 in Kangwondo. Forest soil pH increased with the distance from pollution sources to suburban areas at constant rate within short ranges (up to 30 km) and at decreasing rate within long ranges (up to 200 km). On the contrary, sulfur content in soils decreased every year except in Yeochon region. Base saturation of forest soils in polluted regions were all below 20% level compared with 70% in Kangwondo region. Active aluminum content in soils increased with the soil acidification at the highest rate in Yeochon, and the next in Ulsan and Seoul. Heavy metal content such as copper and zinc in tree tissues were the lowest in Kangwondo region, and the next in Yeochon, Seoul and Ulsan.

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Exploring the Theoretical Trends of an Integrated Environmental Design (통합적 환경설계 이론 기초 연구)

  • Ahn, Myung-June;Pae, Jeong-Hann
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.2
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    • pp.14-25
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    • 2009
  • We live in an age which is exponentially growing as the knowledge paradigm is changing. New sites are subject to contemporary landscape architecture function as "fields" in which this hybrid aspect is both actively practiced and becoming a catalyst for change in the area of landscape architecture. With this as its background, this study attempts to deal with how the aspect of integration in environmental design is manifested. For this purpose, the tendencies for the discussion of integration in various fields of practice were examined: planning theories, urban theories, architecture, public environment, engineering, and landscape architecture. As yet, the discussions of interdisciplinary integration, which occur in practice in these respective fields, mainly tend to be oriented toward the effective implementation of the merits of other related fields. Seen from these examples of practice, integrated design approaches can be found in the following three aspects: design objects, respective professional areas, and methodologies of approaches and design. In terms of design objects, the positions of individual design subjects present themselves as most obvious, and integration or combination of the physical targets that come to exist through design can be easily seen. Most examples of integration turn out to be this, in almost every case of which the theme and the target of expression are integrated via a small number of certain methods. In terms of professional areas, what can be mainly evidenced is how the individual subject acts when the subject designs. The strong points of professionals from each field seem to create synergy, achieving through integration optimum results. In terms of methodologies of approaches and design, there are attempts to create integrated approaches as ways of effective decision-making, in which case the integration of all of the interest parties is of primary concern. As yet, few instances have been found in which integrated design has had enough strength to be seen as a concrete design methodology based on practical examples. However, it is encouraging that theoretical approaches and the necessity for integrated design have been identified from multiple perspectives, and that a practical movement such as landscape urbanism has come into active being. The authors of this study find this point in time to be ripe for discussions on integrated practices in terms of environmental design, on the basis of the synthetic approaches mentioned above.

A Study on Root Damage to Street Pavement from the Roots of Roadside Trees in Urban Areas - Focusing on Roadside Trees in Seo-gu, Daejeon City - (도심 가로수 뿌리의 융기특성 연구 - 대전 서구 가로수를 대상으로 -)

  • Tak, Seong-Cheol;Lee, Shiyoung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.3
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    • pp.58-69
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    • 2018
  • This study investigated root damage characteristics and correlations between roadside trees and street furniture through the investigation of the root damage conditions and the current status of roadside trees and street furniture in Seo-gu, Daejeon City where the occurrence of pavement uplift is frequent. The study area was divided into six areas by species of trees as Metasequoia glyptostroboides and Platanus occidentalis focusing on the streets that were installed with trees chest height and 8cm round planted at the time of the development of the Dunsan-dong Housing Site Development in Seo-gu, Daejeon metropolitan city (1990~1994). The damage rate of roadside protection frames (95.3%) was higher than that of curbstones (19.7%) at the study site. Streets without a protective frame were more likely to have damaged pavement. In addition, the frequency of breakage of protective frames was lowered when a drinking water area was increased to more than a certain level. The frequency of the type of uplift in the sidewalk pavement surfaces is in the order of tail type > mounding type > irregular type, and the frequency of the uplift direction is the highest in Direction 1 ($0{\sim}44^{\circ}C$), Direction 2 ($45{\sim}89^{\circ}$), and Direction 3 ($95{\sim}134^{\circ}$) when $180^{\circ}$ of the street direction is based on $90^{\circ}$ parallel to the curbstone. The uplift length is about 31~60cm and it is most often at a height of 3~6cm. When comparing the results of uplift deformation, Metasequoia glyptostroboides was found to be higher than the deformation of Platanus occidentalis. In addition, it can be seen that the larger the length, width and height of the ridge, the larger the deformation becomes. The relationship between the diameter at breast height, the dimension of the pavement width, the frequency of the ridge phenomenon and the deformation amount is not necessarily proportional, and there seems to be a gap due to external factors such as soil humidity and planting base. Therefore there is a need for a multi-directional approach in reducing uplift.