• 한국농공학회논문집
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• 제51권4호
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• pp.67-73
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• 2009

Chemical properties of soil in the proposed horticultural complexes of Saemangeun reclaimed tideland were studied for sustainable development of the newly reclaimed land resources. The soil texture of Gwanghwal, Gyehwa, Mangyeong and Okgu complex area were sandy loam. The pH and ESP (exchangeable sodium percentage) were 7.42 to 7.82 and 61.05 to 73.62 %, respectively. Compared to general agricultural land in Korea, the soil organic matter and other plant nutrients were low. The concentrations of heavy metals in the soil were found to be acceptable except several sites where they doesn't meet the warning standard of agricultural land contamination. Continuous monitoring and interception of external pollutants are suggested for water-soil-plant system conservation.

• 한국토양비료학회지
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• 제45권1호
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• pp.9-15
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• 2012

This study was performed to produce basic data for silty reclaimed tidal lands and to develop techniques of environmentally-friendly utilization in agricultural system. We chose the two sites in Saemangeum reclaimed tidal lands, one (Site I) has been treated with cultivating green manure and conducting the desalinization process through submergence since April, 2007 and the other (Site II) has been under natural condition without artificial treatment. In situ and ex situ physic-chemical properties were determined and comparisons were made for soil profiles examined at these two sites in April 2009. Surface soil of Site I had lower EC and higher field saturated hydraulic conductivity than those of Site II, uncultivated land. Especially, exchangeable sodium content was lowest in Site I Ap1 layer than in other layers. This is probably due to flooding desalination and green manure cultivation. Besides, Ap1 and A2 layers of soil profile in Site I showed brighter soil color and more root observation than those of Site II. This is probably due to green manure cultivation. By the large, for high cash upland crops and intensive agricultural use of silty reclaimed tidal land, site-specific soil ripening such as flooding desalination and green manure cultivation could be useful.

• 한국환경농학회지
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• 제39권4호
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• pp.327-333
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• 2020

BACKGROUND: Through Saemangeum development project, 283 ㎢ of new land is planned to be created and the reclaimed land of 89.7 ㎢ will be used as agricultural land. Therefore, monitoring of soil salinity is required to evaluate the suitability of the land for agricultural purposes. METHODS AND RESULTS: We investigated changes of soil physico-chemical properties, including electric conductivity (EC), of the Saemangeum reclaimed tidal land (1,195 ha) from 2008 to 2017 to obtain basic data for suitable soil management of the Saemangeum reclaimed tidal land. Soil samples were collected from the sites spaced 200 meters apart from each other. Soil analysis results showed that average soil EC was 14.5 dS m-1 in 2008, and decreased to 6.5 dS m-1 in 2014 and to 0.9 dS m-1 in 2017. Accordingly, the soil area below soil EC 4.7 dS m-1 (accepted as farmable soil salinity) increased; 25.0% in 2008, 54.3% in 2014, and 96.9% in 2017. The annual decrease in soil EC was described as y = -1.5756x + 14.6 (R2= 0.96), where y = soil EC and x = elapsed years since 2008. CONCLUSION: The soil salinity have decreased to a level for cultivation of most edible crops. However, since the soil chemical properties, such as soil organic matter were inadequate for the cultivation of crops, it was suggested that management of soil fertility would be important for efficient agricultural use of Saemangeum reclaimed land.

• Ocean and Polar Research
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• 제31권3호
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• pp.277-282
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• 2009

Saunders' gulls (Laurs saundersi) which are listed as globally vulnerable species on the IUCN Red List are distributed in East Asia and breed mainly in China and Korea. Their population is estimated to be between 7,100 to 9,600. Songdo reclaimed lands in the western coast of South Korea are the main breeding sites for these species. However, most of these breeding sites have been seriously disturbed in the last several years because of new urban development constructions. This study was conducted to provide baseline data on the breeding ecology of Saunders' gulls. Since 1998, the breeding population has rapidly increased in South Korea, with the number of nests rising from 85 nests in 2000 to 185 nests in 2005. Egg volume is more variable than breadth or length. Clutch size, hatching and breeding success were $2.9{\pm}0.81$ (n=182, mean$\pm$sd.), 48.07% (75 hatched egg/156 eggs) and 29.08% (155 fledglings/533 eggs), respectively. Factors affecting breeding failure were predation, rainfall, starvation and supernormal clutches. These results are provided along with other cited literature to argue for conservation of Saunders' gulls.

• 한국물환경학회지
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• 제37권3호
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• pp.190-203
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• 2021

Water quality, benthic macroinvertebrate communities, and other factors were investigated to explore the effects of the effluent discharge from a sewage treatment plant into Jwagwang stream in Busan in 2019. During the study period, the flow rate of this stream was in the range of 10,400 m³/day to 52,200 m³/day except for the discharge of about 24,000 m³/day of the effluent. After discharge, the flow velocity increased by about 65% and the water depth increased by about 40%. At sites downstream of the discharge point, BOD, COD, TOC, T-N, T-P, and other water quality values were worse than those of the upstream sites. The periphytic algal chlorophyll-a concentrations in the natural substrata were higher than those of the upstream sites, especially in May and August. However, at sites downstream of the discharge point, the individual numbers of Annelida were decreased and individual numbers of the insecta of arthropoda were increased. Also, species numbers and the diversity and dominance indexes were improved in the sites downstream of the discharge point. The functional feeding groups (FFGs) of collector-filterers were increased and the habitat orientation groups (HOGs) of sprawlers, burrowers, and clingers were especially increased at the sites with additional reclaimed wastewater effluent flow. Regardless of the effluent discharge, BMI, an indicator of ecological stream health using benthic macroinvertebrate species, did not show large gaps between the study points. Although the water quality of the sites downstream of the discharge point was much worse than those upstream, their ecosystem soundness was better than those of the upstream sites from an ecological perspective.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2001년도 정기총회 및 학술논문발표회
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• pp.32-34
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• 2001

• 농촌계획
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• 제26권3호
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• pp.67-77
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• 2020

The purpose of this study was to determine the problems of reclamation sites and the prospects of farming in reclamation areas seen by local governments and the KRC branches in Chungnam, Jeonbuk, and Jeonnam provinces. A mail survey method was used. The survey items were set for 15 items regarding the reclamation site situation, problems, and prospects. Seventy-five copies of the questionnaire were distributed to the local government, and 90 copies were sent to the KRC 165 copies in total. In response to the questionnaire, 72 recipients of the local governments responded, showing a 96% response rate, and 74 (82.2%) of the KRC responded. The overall response rate was 88.5%. The opinions on the rental method of the reclaimed land were found to differ according to the geographic conditions of the reclaimed land, the construction conditions, and the time. Regarding the survey on crops preferred for cultivation, rice was highest in both local governments (61%) and KRC (46%). When cultivating field crops in reclaimed land, 56% of local governments and 57% of KRC considered salinity as the most problematic or resolvable problem. Regarding growing other field crops in reclaimed land, salt and drainage problems were recognized as the biggest obstacles in all reclaimed land. As for technologies that need to be applied first for the future agriculture of reclamation land, KRC responded with automatic water management (48%) and local governments responded with unmanned agricultural machinery (32%). In order to diversify the land use in the reclamation area, it is necessary to reduce salt damage and ensure systematic maintenance, employing, for example, automatic water management facilities and drainage improvement methods. The results of this study can set a land use direction for reclamation sites and provide useful information for use in various forms.

• 미생물학회지
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• 제6권4호
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• pp.131-140
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• 1968

The soil of the reclaimed tidal land, located in Chogi-ri, Is. Kanghwa, Korea was used in this experiment. The experimented soil samples were collected from 18 sites with its time elapsed after the shore-protection works, soil-depth and the vegetation of saline plants, and at each site samplings were conducted monthly from March through October, 1968, for the purposes of examining the changes of microbial populations for the microbes such as bacteria, actinomycetes and fungi, by using the dilution plate method. The numbers of the microbes in these soils generally showed lower levels comparing with those of other soils. The more time elapsed after the reclamation, the higher numbers of the microbes inhibited the soils. Higher populations were there in the surface soils than in the lower part of the area. The surface soils included comparatively better conditions in aeration and contents of organic matter than in the lower part, and this fact was. same as in general soils. However, not so was this in the case of March, April and October due to the higher soil temperatures in the lows. At the experimental sites where the halophytes such as Salicorniu were grown vigourously, the more densly the plants grew, the higher populations of actinomycetes and fungi were, but not in the case of bacterial population. This means, in this soil with dense Salicornia, it is difficult to obtain good-natured soils in short time without a higher population of bacteria. For the rapid utilization of the land soil, in this view of point, the methods increasing the number of bacteria in the soil are needed as well as the cultivation and harvesting Salicorniu which indicated in the privious paper(Hong, et al., 1969a). According to the results of this experiment, the changes of soil-microbial populations in the reclaimed tidal land soil containing high salinity depend deeply upon the interrelations of many environmental factors such as soil-salinity, soil-components and contents, concentration of organic matters, pH, aeration, and air and soil temperatures, as in the general soils.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권6호
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• pp.27-35
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• 2021

This study examined the possibility of reutilization of soil reclaimed from contaminated sites after completing remediation. The current status of soil remediation methods in Korea was reviewed and physicochemical properties of soil before and after remediation processes were examined to access the recycling possibility of reclaimed soils based on Recycling Aggregate Quality Standard. The most commonly practiced soil remediation techniques are soil washing, land farming, and thermal desorption. These techniques tend to deteriorate various soil properties including electrical conductivity(EC), organic matter content(OM), available P₂O₅, and cation exchange capacity(CEC). Evaluation of the properties of soil retrieved after each remediation process indicated soil washing may yield the most suitable soil for use as a filling, covering, back-filling, road pavement, and blocking materials, In addition, the soils reclaimed from land farming and thermal desorption have potential utility as a filling, covering and road pavement materials.

• Journal of Ecology and Environment
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• 제32권2호
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• pp.115-121
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• 2009

In order to elucidate the mechanisms affecting plant distributions in the reclaimed dredging area in the Gwangyang steelworks, in the Gwangyang Bay, Korea, we examined soil characteristics and plant distributions in four study sites and a control site in the study area. Desalination occurring along a gradient with increasing elevation, resulting in decrease of soil pH, EC, P, K, Cl, Ca, Mg, and salt and an increase in soil T-N, silt, clay contents. From site 1 (the lowest-elevation site) to site 5 (the highest-elevation site), halophytes decreased in abundance and nonhalophytes increased. The dominant species in each site were: Phragmites communis, Limonium tetragonum, and 12 additional species at site 1, Carex pumila, Suaeda japonica, and 15 additional species at site 2, Spergularia marina, Scirpus planiculmis, and 22 additional species at site 3, Miscantus sinensis, Lespedeza bicolor, and 26 additional species at site 4 and Pinus thunberii, Rhododendron mucronulatum, and 39 additional species at site 5, which resembled a naturally-occurring P. thinbergii community. Cluster analysis of the vegetation data matrix grouped the 35 plots into 5 major groups, and cluster analysis using the soil environment data matrix revealed 4 major groups. CCA of the floristic and environmental data matrix showed a positive relationship of SAR, EC, Na, Cl, and Ca, which are related to salt, in the $1^{st}$ axis and $2^{nd}$ axis, but negative relationships for altitude, organic contents, silt, and clay contents. Notably, plant species in the reclaimed dredging area that were separated along the $1^{st}$ axis showed strong relationships with factors that related to salt. Long-term exposure to natural rainfall in the reclaimed dredging area changed the soil characteristics, such as salinity. This change in soil characteristics might alter the SAR, which affects plant survival strategies in a given habitat. These results strongly indicated that factors related to salt and elevation play important roles in determining the overall plant distribution in the reclaimed dredging area.