• Title/Summary/Keyword: 延安

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Characteristics of the Species Composition by Plant Community in the Shincheon Wetland of Mangyeong River, Jeonbuk (만경강 신천습지의 식물군락별 종조성적 특성)

  • Kwang-Jin, Cho;Jung-A, Lee;Jeoncheol, Lim;Yeounsu, Chu
    • Journal of Environmental Impact Assessment
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    • v.31 no.6
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    • pp.409-422
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    • 2022
  • Riverine wetlands are an important element of the river ecosystem and account for approximately 38% of the inland wetlands surveyed so far. The Shincheon Wetland located in Mangyeong River is also a channel wetland as the flow rate is slowed by the constructed weirs, leading to sediment accumulation. To identify the conservation value and ecological characteristics of Shincheon Wetland, its vegetation and plant diversity were identified using a phytosociological method, and a total of 45 vegetation-related datasets were collected. Overall, 24 plant communities, comprising a total of 153 taxa (49 families, 117 genera, 146 species, 2 subspecies, 5 varieties) were identified. The plant with the highest appearance rate in the communities was Humulus japonicus Siebold & Zucc. In addition, annual herb species, including Rumex crispus L., Bromusjaponicus Thunb., Erigeron annuus (L.) Pers., and Artemisia indica Willd. were frequently observed to be growing in the secondary grassland. Naturalized plants were surveyed in the 38 taxa; the urbanization index was 10.3% and the naturalized index was 24.8%. Plant communities were largely classified into submerged vegetation, floating and floating-leaved vegetation, annual and biennial vegetation, perennial herb vegetation, and woody vegetation. The distribution of plant communities reflecting various habitats, including the lentic and lotic zone maintaining a constant water depth, littoral zone experiencing intermittent water level fluctuations, and dry floodplain environment was also confirmed. Overall, plant community development plays an important role in the habitat for wild animals; therefore, it is expected to positively impact biodiversity enhancement.

A Study on the Optimal Site Selection by Constraint Mapping and Park Optimization for Offshore Wind Farm in the Southwest Coastal Area (서남해 연안 해상풍력 발전단지 지리적 적합지 선정 및 최적배치에 관한 연구)

  • Jung-Ho, Kim;Geon-Hwa, Ryu;Hong-Chul, Son;Young-Gon, Kim;Chae-Joo, Moon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.6
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    • pp.1145-1156
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    • 2022
  • In order to effectively secure site suitability for the development of large-scale offshore wind farms, it is essential to minimize the environmental impact of development and analyze the conflicts of benefit between social, ecological, and economic core values. In addition, a preliminary review of site adequacy must be preceded in order not to collide with other used areas in the marine spatial plan. In addition, it is necessary to conduct local meteorological characteristics analysis including wind resources near Jeollanam-do area before project feasibility study. Therefore, wind resource analysis was performed using the observation data of the meteorological mast installed in Wangdeungnyeo near Anmado, Yeonggwang, and the optimal site was selected after excluding geographical constraints related to the location of the offshore wind farm. In addition, the annual energy production was calculated by deriving the optimal wind farm arrangement results suitable for the local wind resources characteristics based on WindSim SW, and it is intended to be used as basic research data for site discovery and selection of suitable sites for future offshore wind farm projects.

A Study of Environmental Conditions of Survival Rate and Relative Growth Rate in Female Gametophyte of Undaria pinnatifida for Toxicity Assessment (생태독성평가를 위한 미역(Undaria pinnatifida) 암배우체 생존율 및 상대성장률의 환경조건 연구)

  • Ju-Wook, Lee;Yun-Ho, Park;Bo-Ram, Sim;Hyong-Joo, Jeon;Seung, Heo;Un-Ki, Hwang
    • Journal of Marine Life Science
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    • v.7 no.2
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    • pp.86-93
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    • 2022
  • The ecotoxicity test method using Undaria pinnatifida spore is challenging to use throughout the year. Since U. pinnatifida female gametophytes can be cultured in the laboratory, they can be used for ecotoxicity testing at any time. Changes in female gametophyte survival rate and relative growth rate in U. pinnatifida exposed to various environmental conditions were analyzed. The female gametophyte of U. pinnatifida was exposed to salinity (5~40 psu), temperature (5~30℃), pH (4~10), and light intensity (0~120 μmol photon m-2 s-1). Based on the highest average value, the survival rate of female gametophyte was highest at a temperature of 20℃, salinity 27.5 psu, pH 8, and light intensity 30 μmol photon m-2 s-1. And the relative growth rate was highest at a temperature of 15℃, salinity 35 psu, pH 9, and light intensity of 60 μmol photon m-2 s-1. As a result of this study, the method using the optimal conditions for the survival rate and relative growth rate is expected to be a practical test method that can complement the current method.

Toxicological Assessment to Environmental Stressors Using Exoskeleton Surface Roughness in Macrophthalmus japonicus: New Approach for an Integrated End-point Development (칠게 외골격 표면 거칠기를 이용한 노출 독성 평가: 새로운 융합적 연구)

  • Park, Kiyun;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.54 no.4
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    • pp.265-271
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    • 2021
  • Intertidal mud crab (Macrophthalmus japonicus) is an organism with a hard chitinous exoskeleton and has function for an osmotic control in response to the salinity gradient of seawater. Crustacean exoskeletons change in their natural state in response to environmental factors, such as changes in the pH and water temperature, and the presence of pollutant substances and pathogen infection. In this study, the ecotoxicological effects of irgarol exposure and heavy metal distribution were presented by analyzing the surface roughness of the crab exoskeleton. The exoskeleton surface roughness and variation reduced in M. japonicus exposed to irgarol. In addition, it was confirmed that the surface roughness and variation were changed in the field M. japonicus crab according to the distribution of toxic heavy metals(Cd, Pb, Hg) in marine sediments. This change in the surface roughness of the exoskeleton represents a new end-point of the biological response of the crab according to external environmental stressors. This suggests that it may affect the functional aspects of exoskeleton protection, support, and transport. This approach can be utilized as a useful method for monitoring the aquatic environment as an integrated technology of mechanical engineering and biology.

A Comparative Analysis of Fishery and Marine Environment-related Policies on Estimated Amount of Fishery Debris Caused by Fishing (조업기인 어업쓰레기 발생추정량에 대한 어업 및 해양환경 관련 정책 비교분석)

  • Seong, Eun-hye;Kim, Kyung-shin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.906-917
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    • 2022
  • This study aimed to compare differences according to categories of fishery and marine environmental policies for the (estimated) amount of fishery waste generated by fishing, and to analyze the correlation between associated independent and dependent variables. The independent variables were divided into three dif erent sectors. The first sector included precautionary policies that observed eco-friendly fishing support program, institutional prevention activities, and physical barriers installation. The second sector with the current management policies included the relevant vessel operations, establishment of fishery order, fishery restructuring, and fishery ground clean-up. Thirdly, post-response policies comprised the litter purification from river to shoreline, the collection and removal of marine, sedimentary, and floating debris, purchasing salvaged debris generated while fishing, fishery waste disposal, and repairing damage caused by marine litter. The indicator used was the settlement amount by each program. The dependent variable was the estimated amount of fishery waste and the indicator was the sum of the loss of traps and gill nets and the loss of their appendages. According to the results of Kruskal-Wallis Test, the estimated amount of fishery waste was highest in the East Sea in terms of sea area and the highest in the Si(city) according to basic local municipality. The settlement amount related to the marine environment services was largest in the Gun(county). Further, there were significant differences between Gun(county) and the other regions(Si(city) and Gu(autonomous district)) with respect to most variables. The variables related to the estimated amount of fishery debris were the project purchasing salvaged debris generated while fishing and fishery waste disposal program in the post-response policies.

A Discussion on Container Loss Accidents and Responses During Ship Voyage (선박 운항 중 컨테이너 해상유실 사고 및 대응에 관한 고찰)

  • Hwang, Daejung
    • Journal of Navigation and Port Research
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    • v.46 no.4
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    • pp.331-337
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    • 2022
  • In 2021, the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP), a U.N. advisory research institute, cited container loss as one of six sources of marine litters in shipping. The sinking of the X-P ress Pearl in May 2021 caused a catastrophic environmental pollution accident in which the loaded containers were moved to the shore, and the plastic pellets were loaded inside covered the coast of Sri Lanka. With this history, the International Maritime Organization (IMO) will discuss prevention and follow-up measures for container loss during ship voyages, as an agenda at the 8th Sub Committee on Carriage of Cargoes and Containers meeting in September 2022. To establish Korea's response direction at the IMO meeting, this study identified major causes of container loss accidents, and considered the response through analysis based on the accident investigation report and related professional data. As a result, it was found that the major cause of container loss during voyages was the enlargement of container ships, bad weather, and poor loading of containers. In particular, the need to prepare countermeasures for the deterioration of the operational safety of large container ships due to bad weather was identified. Additionally, integrated monitoring of the implementation of international conventions is required, for the safe sea transportation of container cargo. In particular, in terms of preservation of the marine environment, it is necessary to supplement the system for the recovery of lost containers. Finally, it was found that it is necessary to establish systems that can complement each other in the shipbuilding and shipping industries, in terms of shipbuilding as well as ship operation, to fundamentally prevent container loss accidents at sea. It is judged that it is difficult to resolve the various factors of container loss at sea during voyages, by responding from an individual perspective.

A Study on the Method of Manufacturing Lactic Acid from Seaweed Biomass (해조류 바이오매스로부터 Lactic acid를 제조하는 방법에 관한 연구)

  • Lee, Hakrae;Ko, Euisuk;Shim, Woncheol;Kim, Jongseo;Kim, Jaineung
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.28 no.1
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    • pp.1-8
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    • 2022
  • With the spread of COVID-19 worldwide, non-face-to-face services have grown rapidly, but at the same time, the problem of plastic waste is getting worse. Accordingly, eco-friendly policies such as carbon neutrality and sustainable circular economy are being promoted worldwide. Due to the high demand for eco-friendly products, the packaging industry is trying to develop eco-friendly packaging materials using PLA and PBAT and create new business models. On the other hand, Ulva australis occurs in large quantities in the southern seas of Korea and off the coast of Jeju Island, causing marine environmental problems. In this study, lactic acid was produced through dilute acid pretreatment, enzymatic saccharification, and fermentation processes to utilize Ulva australis as a new alternative energy raw material. In general, seaweeds vary in carbohydrate content and sugar composition depending on the species, harvest location, and time. Seaweed is mainly composed of polysaccharides such as cellulose, alginate, mannan, and xylan, but does not contain lignin. It is difficult to expect high extraction yield of the complex polysaccharide constituting Ulva australis with only one process. However, the fusion process of dilute acid and enzymatic saccharification presented in this study can extract most of the sugars contained in Ulva australis. Therefore, the fusion process is considered to be able to expect high lactic acid production yield when a commercial-scale production process is established.

Proposal for the groundwater based countermeasures to secure water resources considering regional characteristics of water resources vulnerable areas (국내 수자원 이용 취약지역의 지역 특성을 고려한 지하수 기반 수자원 확보 방안 제시)

  • Kim, Geon;Lee, Jae-Beom;Agossou, Amos;Yang, Jeong-Seok
    • Journal of Korea Water Resources Association
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    • v.55 no.3
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    • pp.191-203
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    • 2022
  • This study is a follow-up study of vulnerable areas according to the vulnerability assessment of groundwater resource management in Korea. In this study, an optimal operation plan for groundwater resource management was proposed for areas vulnerable to groundwater resource management in Korea derived from previous studies. Prior to presenting the optimal operation plan for groundwater resource management, this study grasped the current status of changes in groundwater level and seawater penetration area for vulnerable areas using MODFLOW, a groundwater flow analysis program. As a result of the analysis using basic data for 10 years from 2009 to 2018, the groundwater level fell and the sea infiltration area increased. The final purpose of this study, the optimal operation plan for groundwater resource management, was selected as a total of four alternatives that can be expected to have positive effects to increase groundwater level and reduce seawater penetration. As a result of analyzing the amount of change in groundwater level and seawater penetration by applying the selected optimal operation plan, positive effects were found in all methods. It is expected that the optimal operation plan for groundwater resource management proposed in this study will be applied not only to vulnerable areas of groundwater resources in Korea but also to areas requiring development to establish efficient groundwater resource management measures.

Vehicle Detection and Ship Stability Calculation using Image Processing Technique (영상처리기법을 활용한 차량 검출 및 선박복원성 계산)

  • Kim, Deug-Bong;Heo, Jun-Hyeog;Kim, Ga-Lam;Seo, Chang-Beom;Lee, Woo-Jun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.7
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    • pp.1044-1050
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    • 2021
  • After the occurrence of several passenger ship accidents in Korea, various systems are being developed for passenger ship safety management. A total of 162 passenger ships operate along the coast of Korea, of which 105 (65 %) are car-ferries with open vehicle decks. The car-ferry has a navigation pattern that passes through 2 to 4 islands. Safety inspections at the departure point(home port) are carried out by the crew, the operation supervisor of the operation management office, and the maritime safety supervisor. In some cases, self-inspections are carried out for safety inspections at layovers. As with any system, there are institutional and practical limitations. To this end, this study was conducted to suggest a method of detecting a vehicle using image processing and linking it to the calculations for ship stability. For vehicle detection, a method using a difference image and one using machine learning were used. However, a limitation was observed in these methods that the vehicle could not be identified due to strong background lighting from the pier and the ship in the cases where the camera was backlit such as during sunset or at night. It appears necessary to secure sufficient image data and upgrade the program for stable image processing.

Study on the Risk Assessment of Collision Accidents Between Island Bridge and Ship Using an Image Processing Method (영상처리기법을 활용한 연도교와 선박간의 충돌사고 위험성 평가에 관한 연구)

  • Da-Un Jang
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.7
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    • pp.1111-1119
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    • 2022
  • Tourism projects through islands in the waters of Sinan-gun became active, and as a result, a total of 13 marine bridges connecting islands were completed. However, the marine bridge constructed in the fairway is dangerous for traffic. Particularly, in the case of the marine bridge connecting two islands, the width of the fairway is extremely narrow, therefore the risk is higher. In this study, we evaluated the risk of collision between marine bridge piers and ships using the IALA Waterway Risk Assessment Program (IWRAP), a risk assessment model for port waterways, based on a maritime traffic survey on the coastal bridge in Sinan-gun. The results, indicated that No.1 Sinan bridge had the highest probability of collision and most of the transit ships were coastal passenger ships. In addition, No.1 Sinan bridge was the place where the most collision accidents occurred among the marine bridge piers in the target sea, and the cause this study was analyzed. An analysis of the satellite images of the sea environment of No.1 Sinan bridge using an image processing method, confirmed that obstacles that could not be seen in the chart existed nearby the bridge. As a result, traffic was observed to be concentrated in one direction, unlike two-way traffic, which is a method of inducing traffic of bridges to avoid obstacles. The risk cause analysis method using the image processing technique of this study is expected to be used as a basic research method for analyzing the risk factors of island bridge in the future.