• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.1
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• pp.73-81
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• 2023

To understand salinity status of fresh water and paddy soils and the susceptibility of rice to salinity stress of Gunnae reclaimed tidelands, salinity monitoring was conducted in rainy and dry seasons. For fresh water, a high salinity was observed at the sampling location near the sluice gate and decreased with distance from the gate. This spatial pattern of fresh water salinity indicates the necessity of spatial distribution of salinity in the assessment of salinity status of fresh water. Interestingly, there was significant correlation between rainfall amount and salinity, implying that salinity of fresh water varies with rainfall and thus it may be possible to predict salinity of water using rainfall. Soil salinity also higher near the gate, reflecting the influence of high saline water. In addition, the groundwater salinity also high to threat rice growth. Though soil salinity status indicated low possibility of sodium injury, there was changes in soil salinity status during the course of rice growth, suggesting that more intensive monitoring of soil salinity may be necessary for soil salinity assessment. Our study suggests the necessity of intensive salinity monitoring to understand the spatio-temporal variations of salinity of water and soil of reclaimed tideland areas.

• Journal of Wetlands Research
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• v.7 no.1
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• pp.93-106
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• 2005

This article is based on the findings of problems and limits in implementing integrated coastal management strategy in Shihwa Lake area to develop management framework, mechanisms and processes that insure the participation of various stakeholders in making decisions for sustainable development of reclaimed land. The project performance of the Shihwa Comprehensive Management Plan for Water Quality and Environment Restoration formulated in 2001 was evaluated and reviewed to give some valuable guidance for reducing the wide gap between integrated planning and implementation. Managing inter-sectoral conflicts among future land uses in Shihwa reclaimed area is one of the most important issues to make progress in integrated coastal management. There is a urgent need of developing scientific decision-supporting tools for evaluating the alternative scenarios as well as capacity building programs for local stakeholders.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.2
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• pp.29-34
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• 2009

A series of laboratory model tests and numerical analysis is performed to analyze characteristics of desalination and to predict a period of desalination for subsurface saturated soil in Saemanguem reclaimed area. The results show that quantity of desalination is small as salinity of water is increased. On the contrary, quantity of desalination is increased as salinity of soil is high. In order to decrease the salinity to 10 % of initial salinity of soil at depth of 2 m, it takes 11 years to desalinate the soil 50 m away from drainage ditch. For soil at depth of 1.5 m only 1 year to desalinate the soil near drainage ditch. Also, water head of 80 cm is required to desalinate to 10 % of initial salinity for 60 cm thick soil. Because the following results is based upon the Saemangeum soil, an application of this result for another field will be cautious. More research will be required on this matter.

• Journal of Plant Biology
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• v.13 no.3
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• pp.1-16
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• 1970

Field studies were conducted with kusabue variety and factorial design of 12 treatments composed of 3 levels, 10 kg, 15 kg and 20 kg of N per 10 a , and 4 levels of 80, 100, 120, and 140 hills per $3.3m^2$ plot in reclaimed slaty area having an average of 0.48% salt concentration. The law of spacing effect was observed in the increase of the number of stems at any application levels of N, and the increased N application exceeding 15 kg N per 10 a did not increase the number of stems in maximum tillering stages. The light recieving efficiency of plant population was greatly reduced by close planting when compared with the effect of increased N applications in heading stage. The spacing effect on the C/F ratio was not noted but was reduced markedly by the increased N applications, accordingly the spacing effect on rough rice yields to the LAI was less than by the increase N application. Closer spacing increased the number of panicle, and non-effective stems, decreased the number of grains per panicle and panicle weight. The increased N applications also increased the number of panicle, reduced the weight of 1,000 grains and the ratio of matured grains. It was recommended to plant 100 hills per $3.3m^2$ with the application of 15 kg N per 10 a in the reclaimed salty area of Korea.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.380-387
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• 2012

A complex seismic survey, which is nondestructive inspection, is used often recently in estimating the location of reclaimed cultural assets. Such a method is the best way to estimate the location of cultural assets most effectively in a short time at a construction site. This study estimated the reclamation location of a cultural asset by using magnetic gradient survey, earth resistivity survey, and ground penetrating radar survey (GPR) in order to figure out the distribution territory in the area with possibility of creation of reclaimed cultural assets in the past. As a result, it was located at +15m on the X axis and +90m on the Y axis on the floor plane coordinate of the study target area. It was shown that the major axis is about 20m long in the north-northeast direction and the width is about 5m. The depth of development distribution of anomaly zone was estimated as about 1.5~3.0m. Geophysical survey is expected to be used as a efficient and accurate way to excavate the reclaimed cultural assets in future.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.48-52
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• 2011

The effect of soil water content on the transformation potential of N compounds derived from hydrolysis of urea applied in a reclaimed tidal soils which was saline-sodic was observed to evaluate nitrification rates of urea. Soil samples were collected from Moonpo series at the newly reclaimed area in Saemanguem. For the transformation potential of N compounds from urea (46% N), newly reclaimed tidal soils (RS) were amended with urea at the rates of 0, 10, and 20 kg $10a^{-1}$. With leachate obtained from the incubated RS in a leaching tube at $25^{\circ}C$, urea hydrolysis and nitrification were measured for a total of 30days. The cumulative amounts of $NO_3{^-}$-N in each of the four soils treated with urea was linear with time of incubation. Results showed that increase in pH occurred with increasing application rate of urea and volumetric water content due to hydrolysis of urea. The total N in the RS was decreased with incubation time, indicating that rates of urea hydrolysis was influenced by soil moisture conditions. Also, the cumulative amount of nitrate in RS gradually increased with increase in time of incubation.

• Journal of Ocean Engineering and Technology
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• v.24 no.1
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• pp.68-75
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• 2010

Recently, the intensity and frequency of typhoons have been on the increase due to unusual weather phenomena and climate change. In particular, on September 13, 2003, typhoon MAEMI (0314) caused heavy damage in the provinces of Busan and Gyongnam, but also provided an opportunity to perform a variety of studies on storm surge. According to investigation reports on the damage resulting from typhoon MAEMI, the areas where coastal inundation occurred were located in reclaimed land under coastal development. In this study, through an image data analysis of historic and present day typhoons affecting Masan, we found that the inundation damage areas corresponded to reclaimed lands. Therefore, using the area around Busan, including the southeastern coast of Korea where typhoons lead to an increased storm surge risk, we performed a storm surge/inundation simulation, and examined the inundation effect on reclaimed land due to the intensified typhoons predicted for the future by climate change scenarios.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.745-751
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• 2011

In most agricultural soils, ammonium ($NH_4^+$) from fertilizer is quickly converted to nitrate ($NO_3^-$) by the process of nitrification which is crucial to the efficiency of N fertilizers and their impact on the environment. However, nitrification studies have been studied extensively in agricultural soils, not in a newly reclaimed tidal soil which show saline-sodic and high pH. Therefore, understanding the fate of nitrogen species transformed from urea introduced into reclaimed tidal soil is important for nutrient management and environmental quality. This paper reviewed studies regarding to transformation and fate of nitrogen sources such as urea under the circumstances of a reclaimed tidal soils located in a western coastal area.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.2
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• pp.59-67
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• 2009

A study on fugitive dusts was conducted at Saemangeum reclaimed land located in Gim-je area. The monitoring result on the fugitive and suspended dust was significantly affected by the farming activities (harvesting and land cultivation) and vehicles passing nearby the measuring points. The concentration of the fugitive dust generated from the reclaimed land was reduced remarkably by the effect of halophyte present on the ground and the tide embankment. Comparing the data collected in 2006 and 2007, the concentrations of TSP and PM10 decreased by 47.4% and 29.5%, respectively. After harvesting operations at paddy field, TSP increased by 22% while PM10 increased by 54%. The concentration of a Cl- which is a representative ion of sea-salt decreased to about 35% in 2007 compared with 2006. This represents that the inside area change and plant covering rate affected on the decrease of fugitive dust. The correlation analysis for the compounds of topsoil at each measuring point shows that near the coastline is more comparable. The canopy of halophyte in the source area also increased which reduced the fugitive dust remarkably. The dust distribution measured by dust spectrometer at the same point shows that most particles are $0.5{\mu}m$ to 2um size but not greater than $5{\mu}m$.

• KIEAE Journal
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• v.6 no.3
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• pp.43-48
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• 2006

This paper aims to suggest ways of institutionally improving standards that must be applied when installing Water Reclamation/Reuse (WRR) system based on efficiency analysis. Currently, the standard for WRR system establishment requires that the system should treat more than 10% of used water in the building of over $60,000m^2$ in total area of all floors, but our research has found that it would be more effective to change the standard to $150-m^3-per-day$ reclaimed water or the total area of all floors of $30,000m^2$ ($50,000m^2$ in the case of an office building). In other words, what this paper suggests is not a one-size-fits-all standard based on the total area of all floors, but a reasonable and flexible standard that takes into account efficiency and a unit water usage according to a building's purpose. Furthermore, this paper recommends a new WRR standard that can be applied to large-scale land development for housinglots, like the New Town. The recommendation is based on the economic analysis that the WRR system will ensure efficiency only if the amount of reclaimed water is over 4,000 tons per day, which corresponds to 4 millions square meters of housinglots. Regarding the size of the established facility, this paper suggests changing the standard, which is now set at over 10% of water usage, to what is relative to the total amount of use of reclaimed water in order to ensure efficiency and promote use of reclaimed water. In addition, this paper proposes that governmental support should be offered not only to facility owners, who are recipients at present, but also to facility builders. By doing so, those who donate a facility to the government, central or local, after building it, can be provided with substantial aid. Therefore, the application of the institutional improvement suggested in this paper is expected to create environment-friendly living conditions and boost the quality of life by encouraging people to secure water resources efficiently in buildings, and in a wider range, in cities.