• Journal of the Korean association of regional geographers
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• v.3 no.2
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• pp.195-208
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• 1997

On the basis of the topographic maps in the 1910's and 1990's and the classification map of Landsat TM satellite image photographed on Sept 1, 1996, the spatial distribution and the current situation concerning tidal flats in Korea were studied by measuring the area with GIS Arc/Info system and examining the regional condition required to develop the tidal flats. The results are as follow; The tidal flat resources in Korea cover an area of about 3800 square meters, including the reclaimed one since the 1910's. And they are widely distributed in the west coast of South Jeonla, Kyunggi bay, Asan bay, the south coast of South Jeonla, Kunsan bay, Chunsoo bay, and the coast of South Kyungsang and Pusan when put in the order from bigger area. Given the area under the construction at present, more than 50% of the tidal flats are reclaimed ones. The tidal flats are being developed especially in Kyunggi and Asan bays because they perfectly measure up to the conditions required. For Kunsan bay, a remarkably good supply system of the alluvial sedimentary materials and a favorable coastline requirement for the coast of the South Jeonla also contribute to the development of the tidal flats. In the case study of Kunsan bay, it was shown that the shape of the tidal flat is making a continuous change and the area is getting bigger in terms of the multi-temporal change of the tidal flat development. However, while in the first half of the 20th century, the increasing rate of the area was considered to be rather high, it is considerably lowered almost to a standstill in the latter half of the century.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.447-453
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• 2009

Vegetation distribution and soil salinity were surveyed on the conservation plot in the Daeho reclaimed tidal land, in where the plants species distribution was more various than a periodically inundated tidal flat and the early stage of reclamation. According to the soil salinity where the vegetation patches were occurred, the mono patches of Salicornia europaea, Suaeda maritima, and Suaeda glauca were distributed in the average range of 31.05 dS/m in soil salinity, the mixed patches of them were distributed in the average range of 42.75 dS/m. Therefore, Salicornia europaea, Suaeda maritima, and Suaeda glauca showed strong salt tolerance. The mono patches of Aster tripolium, Sonchus brachyotus, and Scirpus planiculm were distributed in the range of 11.73 dS/m in soil salinity, and the mixed patches were distributed in the average range of 9.43 dS/m. Therefore Aster tripolium, Sonchus brachyotus, and Scirpus planiculmis showed moderate salt tolerance. The mono patches of Imperata cylindrica, Trifolium pratense, Miscanthus sinensis, Setaria viridis, and Trisetum bifidum were distributed in the range of 2.42 dS/m in soil salinity. These species showed characteristics of glycophytes with weak salt tolerance. The distribution of vegetation patches was influenced by the soil salinity as pioneer halophytes patches occurred at higher soil salinity zone than facultative halophytes patches, glycophytes patches occurred at lower soil salinity zone than facultative halophytes. These results suggested that occurrence of plant species and plant distribution type might be useful index to evaluate the soil salinity and desalinization in the reclaimed land of the midwest coastal area of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.238-242
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• 2003

Reclaimed tidal areas for rice cultivation are irrigated with salt mixed water when there is severe drought. Therefore, we identified the critical concentration of saline water for rice growth on a reclaimed saline soil in Korea. The experiment was conducted at the Kyehwado substation of the National Honam Agricultural Experiment Station (NHAES) during 2001-2002. Two experimental fields with 0.1-0.2% for low soil salinity and 0.3-0.4% for medium soil salinity levels were used. The experiment involved four levels of salt solution mixed with sea water (at 0.1, 0.3, 0.5, 0.7%) compared with a control using tap water in a split-plot design with three replicates. Saline solution was applied only two times at seedling stage (10 DAT and 25 DAT) for 5 days. Gyehwabyeo and dongjinbyeo, japonica rice varieties, were used in this experiment. Plant height and number of tillers sharply decreased in the 0.5% saline water in low soil salinity level and 0.1% in medium soil salinity level. For yield components, panicle number per unit area and percentage of ripened grain dramatically decreased in the 0.5% saline water in low soil salinity and 0.1% in medium soil salinity level. But 1,000-grain weight of brown rice decreased sharply in the 0.5% saline water in low soil salinity and 0.3% in medium soil salinity, indicating that this component was not much affected unlike other yield components. Milled rice yield decreased significantly with saline water level in both low and medium soil salinity. In the 0.7% low saline soil, the yield index was only 36% compared with the control. In medium soil salinity, even the control plot showed only 62% yield index compared with the control in the low soil salinity treatment. Results indicated that the critical concentration of saline water for rice growth in terms of economical income of rice production was 0.5% in low soil salinity and tap water in medium soil salinity.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.5
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• pp.318-323
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• 2008

We studied on the effects of slurry composting and biofiltration liquid fertilizer (SCBLF) on growth of two-year-old poplar clones planted in a reclaimed land mounding soil. The soil on the experimental site had lower concentrations of both exchangeable cations and salinity than before reclamation. However, the content of organic matter was low compared with the most soils. We applied SCBLF to the poplars six times and 5 L in each time for 80 days. Ten clones of six poplar species or hybrids were tested in this study: Populus alba ${\times}$ P. glandulosa(Clivus, 72-30, 72-31, Bongwha1), P. deltoides ${\times}$ P. nigra(Dorskamp), P. deltoides(Lux) ${\times}$ P. deltoides(Harvard)(97-19), P. euramericana(Eco28, I-476), P. nigra ${\times}$ P. maximowiczii(62-2) and P. Koreana ${\times}$ P. nigra var. italica(Suwon). Growth performance varied more among clones than among species. Average height growth of treated plots was 18% greater than control, and clones Clivus, 97-19, Eco28 and Dorskamp were more vigorous than other clones. Diameter at breast height in treated plots was 41% greater than control, and 97-19, Dorskamp, Eco28 and Clivus were the four best clones in this respect. Mean leaf area of treated trees was 26% greater for control trees. Chlorophyll content was similar between treated and controlled trees. Total nitrogen values in leaves were much higher in treated trees 18%. SCBLF treatment on poplars planted in reclaimed land helped tree growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.305-309
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• 1983

To know the effect of desaltation in the reclaimed tidal fields on the succession of vegetation and on the root hair formation of paddy rice, reclaimed fields in Kang Hwa Island, Nam-Yang Bay and Ke-Hwa Island were investigated during summer crop season in 1982. The obtained results can be summarized as followings. l) In the highly salty and water logged areas of reclaimed tidal fields, the first dominating species of higher plant were observed to be Salicornia herbacea L. and Suaeda japonica Makino. With the continued desaltation, Chemopodium virgatum Thumb. occurred in the vegetation. After this transition, the dominating species were composed of Scirpus maitimus L. and Phragmites communis Trin. At the S. maitimus and P. communis dominating salinity level, rice cultivation was safe from the salt damage. 2) In the water logged area, Artemisia capillaria Thunb. and Aster tripolium L. took the place of dominating species after S. herbacea and S. japonica. At this salinity level, graminaceous weeds began to immigrate. 3) In dry areas, Suaeda asparagoides Makino and Suaeda maritima were the first appearing dominant species. Atriplex subcordata Kitakawa was also observed in sucy dry areas, but colony formation was not observed. 4) Plants immigrated slowly into dry areas from the already vegetated water logged areas with the continuation of desaltation. 5) The high soil salinity level affected the root hair formation of rice by reducing both the rate of root hair formation and the length of root hairs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.339-345
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• 2009

This experiment was carried out to identify the proper transplanting time at reclaimed saline land in the southwestern area of Korea from 2006 to 2007. The rice cultivars tested were Unkwangbyeo(Early maturing one), Gopumbyeo(Medium maturing one) and Samgwangbyeo, Sindongjinbyeo, Cheonghobyeo, Hopyeongbyeo(Mid-late maturing one). The results are summarized as follows. No. of spikelet per the unit area was lower at transplanting on May 20 and wasn't different in those of the other transplanting time. The ripened grain rate was high transplanted May 20 in Unkwangbyeo, but high transplanted from June 1 to June 20 in Mid-late maturing Cultivar. The yield of head rice was high transplanted June 10 and June 20 in Unkwangbyeo, Sindongjinbyeo, Hopyeongbyeo, but June 1 and June 20 in Samgwangbyeo, Cheonghobyeo. The protein content was high transplanted early in Unkwangbyeo, Samgwangbyeo, and late in Gopumbyeo, Sindongjinbyeo, Cheonghobyeo, but wasn't differ among transplanting time in Hopyeongbyeo. Considering the rice growth, the rice good quality, the yield of milled and head rice, the proper transplanting time was June 10 in Unkwangbyeo, Sindongjinbyeo, whereas was June 10 in Samgwangbyeo, Cheonghobyeo, Hopyeongbyeo.

• Journal of Plant Biology
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• v.7 no.2
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• pp.9-13
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• 1964

As to the up-lnd bamboos, I have reported, in my previous works, that Korea has two species in the genus of Pseudosasa, four in Pleioblastus, and other four in Sasa. In the present work, I dealt with Sasamorpha Purpurascens Nakai var. Borealis Nakai which proved the strongest vitality of all up-land bamboo yet found in various up-lands of Korea, and which might be most important from the utility view-point. This report is chiefly on its procreation. Sasamorpha Purpurascens Nakai var. Borealis Nakai can be found almost everywhere throughout the country, and its leaves and stems are much used in farms in various forms of manufacture. It is also welcomed as the feed for livestocks and as cover plants for aforestation, especially as the excellent means of errosion control on devastated hill sides. It is also widely accepted that it will provide, in the immediate future, abundant sources for the up-land bamboo pulp. As the first phase of my research plan on the subject, I undertook to determine the possible best way of its procreation, for which were included the experiments of inducing the growth of subterranean stems, the entire stand cutting, transplanting, reclaimed planting after burning etc. in order to observe the plant elongation, growing conditon, climatical effect etc. What has been fuond out so far given here as follows: 1) Of the various sections of the country, Mt. Odae area gives out the most excellent Sasamorpha Purpurascens Nakai var. Borealis Nakai(the leaf weight of which is 450 gr.) and Taekwanryong area comes the next class. This species can be transplanted anywhere in the South Korea. 2) The elongation of S.P. Nakai var. Borelais begins at around the middle of May and almost completely stops by the 20th of August. 3) The best studied transplanting season is supposed to be Feb. -April, for those transplanted during that period proved 100% of success. The next best transplanting season may be October. Rain fall does not have so much effect on transplanting as the growing season does. 4) In inducing the subterranean stems, the growing season can be ignored. The root expnsion is most animated during the months of April-June, the most active season for water absorption. Those stems induced during the winter proves more rapid growth. 5) The entire stand cutting shows greater growth than the reclaimed planting after burning and that, the growth is most vigorous during May-July, whereas during the hottest months of Aug-Sept. the growth shows only 5 cm. The new shoots grow slower both in the field of entire stand cutting and in the field of reclaimed planting after burning than in the otherwise fields.

• Journal of the Korean Geosynthetics Society
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• v.10 no.2
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• pp.91-100
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• 2011

This study presents the estimation for the possibility of liquefaction according to the liquefaction evaluation methods in Saemangeum reclamation area for tide embankment, Jeollabuk-do, Korea. Liquefaction estimation is performed by cyclic triaxial tests and seismic response analysis using earthquake records of the long- and short-term. This area appears to have greatly potential of liquefaction from the grain-size distribution curve of the dredged and reclaimed soil in the area. Because the liquefaction can occur in this area if the foundations or buried structures are built at a depth within 10m below ground surface, the meticulous care is required in the design of them in the future.

• Journal of the Korean Professional Engineers Association
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• v.33 no.4
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• pp.68-71
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• 2000

Tideland reclamation in Korea has significant meanings both in securing the staple food supply and in enlarging the limited land resources. Environmentally, that significantly contributes in protecting the sea and the tidelands connected to a reclaimed area from the direct exposure to the environmental destruction by filtering the large volume of contaminant discharged from the inland. Furthermore, within few years after closing a sea dike. formulation of new tideland begins in wide area in front. Therefore, tideland reclamation should not be the one that must be unconditionally objected. Instead, the methodology should be wisely redirected to minimize the environmental disorder. It will be one viable alternative to proceed the tideland reclamation at medium- to small-scales environment-friendly bringing minimal environmental change in the sea.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.11b
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• pp.35-48
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• 1999

The Nakdong River in Korea has formed a delta area .called the Kimhae Plain near the river mouth. Its clay deposit is unusually thick (up to 60m) compared with the clays deposited in other parts of the world. Some parts of the area has been reclaimed with the height of approximately 5 to 7m after installing vertical drains for the development of important new industrial complexes. Settlement measurements were taken during the reclamation works on the soft ground, and it was revealed that the measured settlements were extremely higher than predicted. This paper discusses possible reasons on unusual large settlements from depositional environments of Kimhae clay.