• Korean Journal of Microbiology
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• v.6 no.4
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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.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.1
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• pp.13-22
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• 2005

This paper classifies the topography of the Saemangeum Tidal flats based on Landsat TM satellite images by unsupervised ISODATA method, and analysis of the spatiotemporal changes of the classified shapes. The sedimental topography represents various properties according to the Saemangeum Tidal Embankment progress. We well proceed this study of the sedimental changes and distributions. By specifying the topographic characteristics of inner sea areas respectively, the investigation on the case study area according to the changes of the tidal will be useful in the establishment of land reclamation plan and the land use of the reclaimed area. In addition, the estuary image can be divided into tidal flats and sea surfaces using the band 4, also the detailed topography using the band 5, respectively among Landsat TM 7 bands. This paper contributes to the efficient image processing of the spatiotemporal sedimental changes.

• Journal of the Korean Geographical Society
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• v.38 no.2
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• pp.206-223
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• 2003

Bays and caps represent the physical characteristics of Naepo area in Korea. And reclamation of tidal land presents a clue toward the understanding of regional identities and landscape changes in this area. Reclamation of tidal land in the Garorim bay that is representative of the physical geographies of Naepo area had trended toward 'the diffusion of salt ponds' during Joseon dynasty. Hereafter the Japanese imperialism, the reclamation had tumed to 'the reclamation of arable lands' by drainage. But, at the same time the land use of salt pond that had been the most appropriate strategy of adaptation for the ecological environments of this area has showed a sort of the geographical long-term durability. And the great landlords that had emerged during Japanese imperialism were the Yeom-han(鹽漢, laborers who engaged in salt production) in former times. They as a new local elites have played a leading role in the reclamation of tidal land and the making of regional landscape.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.4 no.3
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• pp.146-155
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• 1992

It has been conventional to treat the land boundary as a fixed one in numerical modeling of tidal flows, particularly in the finite element scheme. However conventional models using the fixed land boundary result in unrealistic tidal flows in inter-tidal zones which exist over wide coastal area in Korea. In this study, a 2-dimensional hydrodynamic model, using finite element method for moving boundary problems was developed. The performance of the model was tested in a rectangular channel with an open boundary at one end and a moving boundary at the other end. The model was applied to calculate the tidal currents in Maro Hae, located in the southwestern part of Korea where wide tidal flats develop. The behavior of tidal currents in the Udolmok and near the tidal flats in the study area was satisfactory when compared with the observed data. Variation of tidal currents due to the construction of Kochunam sea-dyke which barrages large area of tidal flat was presented. The results of this study confirm the efficiency of moving boundary treatment in coastal numerical models.

• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.4
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• pp.37-49
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• 2001

This study was performed in order to produce the basic data for developing prediction techniques of desalinization to be applicable to reclaimed tidal lands at the beginning stage. the desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage. The 5 soil samples used in this study were collected in 4 tidal land reclamation projects. Regression equations were obtained in order to investigate the changes of electrical conductivity during the desalinization of reclaimed tidal lands and to estimate water requirements for desalinization. The results obtained from this study were summarized as follows: 1. According to USDA Salinity Laboratory classification system of salt affected soils the reclaimed tidal land soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage. 2. With the increase of the water requirements for desalinization the electrical conductivity was decreased with high degree of correlationships and the desalinization effects were remakable in both the leaching method and the rinsing method. 3. In case of the leaching method the electrical conductivity had been reduced below the classification value of salt affected soils when the depth o water leached per unit depth of soil (Dwl/Ds) was 0.3 and the desalinization effects showed a tendency to be much the same in each treatment.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.166.2-166.2
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• 2011

Incheon Bay of Korea is one of the most famous regions for high tidal range. Ministry of Land, Transport and Maritime Affairs(MLTM) has implemented preliminary investigation for tidal power energy development in this area since 2006. Through field observations, various kinds of marine data consisting of depth and geography, marine weather, tidal currents, wave, seawater characteristics, geology, marine ecosystem and marine environment were gathered. To use these data efficiently for the determining of feasibility of developing and appropriateness of project scale, spatial data management and application system is essential. Therefore, in this study, the concept, methodology and procedure of spatial data modeling are defined for tidal energy development. Spatial data modeling consists of essential model relating to tidal energy directly and optional model including environmental factors. Essential model is composed with fundamental elements like as depth, geography, and several numerical modeling results(tide, tidal current, wave).

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.365-372
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• 2013

Crop development and nutrient availability are strongly influenced by soil salinity levels. This study was conducted to investigate the effect of rice straw and nitrogen (N) fertilizer for silage barley under various soil salinity levels at Saemangeum reclaimed tidal land. Three levels of rice straw (0, 2.5, 5.0 ton rice straw $ha^{-1}$) and N (0, 150, 225 kg N $ha^{-1}$) were applied at 0.04, 0.23, 0.35% soil salinity levels. Biomass yield of silage barley was influenced by the interactions between rice straw application and N fertilization. Although there was no single effect of rice straw application on biomass yield, it was significantly increased with N application and a rice straw application of 5.0 ton $ha^{-1}$. Sodium content in silage barley was significantly lower at 0.04% salinity level, and but it was statistically increased with increasing soil salinity levels. Forage qualities such as total digestible nutrients and relative feed value of silage barley were significantly higher with N application at 0.04% salinity level, but there was no effect of rice straw application. Soil organic matter content was increased with N and rice straw application regardless of soil salinity level. The results of this study showed that the effect of rice straw and N fertilization on silage barley was influenced by soil salinity levels, which indicates that the management practice of silage barley at Saemangeum reclaimed tidal land should consider soil salinity levels.

• Korean Journal of Ecology and Environment
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• v.47 no.3
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• pp.202-213
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• 2014

More than half of all the tidal flats and islands in South Korea are located in Jeonnam. Shinangun accounts for a large amount of these tidal flats and island. This study assessed the value of ecosystem services for 14 administrative units (2 'eup' and 12 'myeon') that have around 1,000 islands in Shinangun, using the method described by Costanza et al. (1997). The assessment involved examining the land use types in Shinangun in relation to ecosystem services value. The finding showed that the tidal flat areas had the highest value of ecosystem services in most of the islands of Shinangun, in particular in Aphae-eup and Jido-eup. The study illustrates how quantitative analysis of land use patterns can help local governments like Shinangun to formulate policy for conservation and sustainaable use of ecosystem services. Especially, tidal flat areas are unique and fragile ecosystem, so it is very importat to make strategies for sustainable development in bioculturally diverse areas. Some suggestions regarding landscape planning in Shinangun are provided.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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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.

• Korean Journal of Remote Sensing
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• v.39 no.4
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• pp.409-423
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• 2023

North Korea is carrying out reclamation activities in tidal flat areas distributed throughout the west coast. Previousremote sensing research on North Korean tidal flats either failsto reflect recent trends or focuses on identifying and analyzing tidal flats. Thisstudy aimsto quantify the impact of recent reclamation activitiesin North Korea's coastal areas and contribute knowledge useful for determining the best remote sensing methods for coastal areas with limited accessibility, such as those in North Korea. Using Landsat-8 OLI images from 2014-2022, we analyzed land cover changesin an area on the west coast of Pyeonganbuk-do where reclamation activities are underway. Unsupervised classification using the normalized difference water index and the random forest classification technique were each used to divide the study area into classification groups, and changes in their areas over time were analyzed. The resultsshow a clear decrease in the water area and a tendency to increase cultivated area,supporting the evidence that North Korea'sreclamation isfor agricultural land expansion.Along coasts behind seawalls, the water area decreased by nearly half, and the cultivated area increased by over 2,300%, indicating significant changes and highlighting the anthropogenic nature of the cover changes due to reclamation. Both methods demonstrated high accuracy, making them suitable for detecting cover changes caused by reclamation. It is expected that further quality research will be conducted through the use of high-resolution satellite images and by combining data from multiple satellites in the future.