• Journal of agriculture & life science
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• v.44 no.6
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• pp.183-189
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• 2010

This study assess the effects of reclaimed wastewater irrigation on grain quality-related properties of milled rice. To conduct the effects of wastewater reuse on rice quality, the contents of amylose, protein, and milled head rice recovery were analyzed. The water and the soil quality were monitored, and the grain characteristic was analyzed using a NIRS (Near Infra-Red Spectroscopy). The value of the grain properties of the rice which was cultivated with the reclaimed wastewater didn't show a big difference from other common rice. The significant difference by each processing distinction was shown at the significance level of 5% in the statistical result.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.1-9
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• 2015

A combined treatment system using multiple source water is becoming important as an alternative to conventional water supply for small-scale water systems. In this research, combined water treatment systems were investigated for simultaneous use of multi-source water including rainwater, ground water, river water, and reclaimed wastewater. A laboratory-scale system was developed to systematically compare various combinations of water treatment processes, including sand filtration, microfiltration (MF), granular activated carbon (GAC), and nanofiltration (NF). Results showed that the efficiency of combined water treatment systems was affected by the quality of feed waters. In addition, a simply approach based on the concept of linear combination was suggested to support a decision-making for the optimum water treatment systems with the consideration of final water quality.

• The Korean Journal of Ecology
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• v.24 no.1
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• pp.27-34
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• 2001

We described the vegetation of a disturbed lagoon wetland in relation to water and soil environments in Kungae lagoon reclaimed 30 years ago. Water depth and soil organic matter showed a great spatial heterogeneity in Kungae wetland which was changed into a freshwater marsh by the dike construction. Detrended canonical correspondence analysis suggested that differences in vegetation structure were primarily the result of variation in water depth or microtopography and soil organic matter Various emergent vegetations were developed in the wetland: species such as Phragmites australis, Calamagrostis epigeios, Carex dispalata and Lythrum anceps in a wide area, hydrophyes such as Typha angustifolia and Scirpus tabernaemontani at the low elevation with deep water, ruderals such as Bidens frondosa and Persicaria perfoliata near upland with much soil organic matter and sand-dune vegetation such as Carex kobomugi, Diodia tens, Pinus thunbergii and Potentilla egedei var. groenlandica at the high elevation. These results suggest that development of a prototype for wetland restoration from vegetation analysis of other natural lagoons and restoration of natural water tables and hydrologic connections between the diked wetland and the sea are important in the disturbed Kungae wetland.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.81-84
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• 2002

Recently Bentonite mat is applied various structure : External waterproofing for underground structure, A reclaimed land, Artificial lake, Large-scaled civil structure, etc. With these various structure environment, water quality for application of Bentonite Mat affects watertightness. Specially spot with a large quantity of Chloride ion like salt water, degree of watertightness revelation is evaluated and applied. In this study, it is a main goal to investigate watertightness of Bentonite Mat with distilled water and salt water dissolved chloride ion Contents 0.88%. The result of this paper is as follows. 1) Water permeability coefficient of Bentonite Mat : distilled water(1.21$\times$10$^{-9}$cm/sec), salt water(3.12$\times$10$^{-7}$cm/sec). 2) Variation of thickness : distilled water(187%), salt water(108%). 3) Swelling ratio : distilled water(1500%), salt water(350%).

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.252-259
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• 2013

BACKGROUND: Salt accumulation in coastal reclaimed soil can decrease plant growth and productivity, which could lead to considerable variation of methane($CH_4$) emission in a rice paddy. The objective of this study was to evaluate the effect of salt concentration on $CH_4$ emission in a coastal reclaimed soil. METHODS AND RESULTS: The effect of salt concentration on $CH_4$ emission and rice growth characteristics was studied by pot test, which packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Electrical conductivity(EC) of each treatment was controlled by 0.98, 2.25, 5.05 and 9.48 dS/m and $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. The $CH_4$ emission rate was significantly decreased with increase of salt accumulation, but total $CH_4$ flux in EC 5.50 dS/m treatment was lower than those of EC 9.48 dS/m treatment. It seems because of higher content of water soluble $SO{_4}^{2-}$ in EC 5.50 dS/m treatment than those of EC 9.48 dS/m treatment. Rice growth and grain yield were significantly decreased with increase of salt accumulation. Soil properties, especially EC and pH were negatively correlated with $CH_4$ flux, while rice growth characteristics like plant height and tiller number show significantly positive correlation with $CH_4$ flux. CONCLUSION(S): Conclusively, salt accumulation significantly decreased $CH_4$ flux in a rice paddy, which could be useful information for evaluating $CH_4$ flux in reclaimed area in Korea.

• Journal of the Korean GEO-environmental Society
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• v.1 no.1
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• pp.57-63
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• 2000

Volume change of the dredged soils is composed of loss amount of the soil particles flowing over an outflow weir with water and settlements due to both the self-weight consolidation in reclaimed layer and the desiccation at the surface of reclaimed layer. In order to estimate the amount of soil particles flowing over an outflow weir with water, the breakage theory and the results of hydrometer analyses. To verify a validity of the proposed procedure, evaluated loss ratio is compared with various estimates from the other existing methods.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.21-30
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• 2015

PURPOSES : The purpose of this study was to evaluate the performance of rapid-setting polymer-modified asphalt mixtures with a high reclaimed asphalt pavement (RAP) content. METHODS: A literature review revealed that emulsified asphalt is actively used for cold-recycled pavement. First, two types of rapid-setting polymer-modified asphalt emulsion were prepared for application to high-RAP material with no virgin material content. The quick-setting polymer-modified asphalt mixtures using two types of rapid-setting polymer-modified asphalt emulsion were subjected to the following tests: 1) Marshall stability test, 2) water immersion stability test and 3) indirect tensile strength ratio test. RESULTS AND CONCLUSIONS : Additional re-calibration of the RAP was needed for laboratory verification because the results of analyzing RAP aggregates, which were collected from different job sites, did not deviate from the normal range. The Marshall stability of each type of binder under dry conditions was good. However, the Type B mixtures with bio-additives performed better in the water immersion stability test. Moreover, the overall results of the indirect tensile strength test of RAP mixtures with Type B emulsions exceeded 0.7. Further research, consisting of lab testing and on-site application, will be performed to verify the possibility of using RAP for minimizing the closing of roadways.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.640-648
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• 2009

Recently the truction of coastal reclaimation work has been extensively implemented in Korea. The Sondo New City is being established on the reclaimed land from the sea, construction companies of metro construction are planing to pull-out the sheet pile for saving the construction cost. In the case of soft marine clay, it is very difficult to pull-out the sheet pile by using the hydraulic hammer difficult. Therefore, the man of the field must be aware of vibration effect to the ground and the structure. For understanding the vibration effect to the ground during subway construction, the model was formulated with 1/25 braced-cut for subway construction. Scott and Iai(1989) proposed the law of the similarity for other experimental conditions. The laboratory model test was conducted under the vibration condition of sheet pile pulling out. The settlement on the ground surface was measured during the shaking table test. The pore water pressure was also monitored in the upper, middle, and lower layers of soil. The field settlement level and the pore water pressure can be predicted by using the results of the laboratory shaking table test.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.278-287
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• 1998

The halophytes are considered less important in our field, as the land reclamation executed continuously by public or individual. So this research is to use plants more active on the reclaimed land and to verify their utility in the aspect of the landscape planning, design and complementaton. This research is performed at the construction site of Incheon International Airport in Youngjong-do located in West-sea of Korea. Following proposals are the major conclusions drawn from the research:1. The halophytes to be used in the vicinity of the water reservoir in orer to improve the ground for the introduction of new plants and prevent the water contaminatioin. 2. The halophytes to be used as a gound-cover which protects major structures nearby from being damaged by the salt content in the air. 3. Thd halophytes to be used as a unique and panoramic landscape element. They have various colors which change throughout a year. 4. Thd halophytes to be considered as a outdoor recreation resource. The halophytes planted area may be utilized as picnic area, outdoor event plaza, ball game ground, rough in the golf cource and etc. Additional usage of the land include the future rearch site for sea fronted ecological studies and pasture for cows and other livestock.

• KCID journal
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• v.21 no.1
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• pp.1-16
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• 2014

The purpose of this study is to calculate agricultural water demand as considering landuse plan of the farm land on the Saemangeum tidal land reclamation project. This study based on the farm landuse plan(2012) and considered some items which did not included previous work like prevention water for resalinization for paddy and upland and muli-purpose water for upland. This study showed that the agricultural water demand estimated $145.123Mm^3/yr$, which is needed as much $14.792Mm^3/yr$ as more water than previous work. The difference comes from the change of unit water demand. Water demand is possible to be changed if guidelines are improved and detailed design work is completed through further study. Especially, the more studies for prevention water for resalinization in a tidal reclaimed farmland and water demand for a horticulture are needed.