• Journal of the Korean Geotechnical Society
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• v.15 no.4
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• pp.175-184
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• 1999

Several major land reclamation projects such as the Inchon International Airport construction, Songdo New City construction, LNG Tank and LPG storage construction are underway along the coastal line of Inchon in Korea. This study was carried out to investigate the feasible use of waste lime in the land reclamation projects. Waste lime (hydrated lime) used in this study is produced as a by-product in the manufacturing process of $Na_2CO_3$ from local chemical factory in Inchon. This study presents the characteristics of bearing capacity and settlement on the ground formed by layers of waste lime and dredged soil. From the laboratory and in-situ plate load test, the ultimate bearing capacity by in-situ test was 1.25~1.37 times higher than that of the theoretical ultimate bearing capacity. Based on the settlement analysis by Magset- II, the total settlement of layered ground steadly increased up to the ratio of waste lime depth 0.2 and therefore rapidly increased with the increase of waste lime depth. The results of the present study indicate that the ratio of waste lime depth for reclamation work is about 0.2.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.4
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• pp.387-397
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• 2021

Most of Korea's agricultural water is supplied by reservoirs, so dependence on them is very high. Accordingly, it is important to reduce this dependence and provide a stable agricultural water supply by utilizing an applicable alternative water source. Therefore, in this work, scenarios for different land uses were constructed, and an optimal water supply plan using rainwater and reused sewage water - which are alternative water sources - was created. A study was also conducted to determine the optimal capacity of a rainwater facility. From the analysis, a stable water supply was achieved in the scenario of maximum utilization of rainwater by changing an existing paddy area to a greenhouse area, and about 0.82 ton of flow capacity was required for 1 mm of rainfall on farms utilizing rainwater. As a result of analyzing the optimal scenario to derive the ratio of the storage capacity per unit water collection area, the rainwater storage capacity determined through MODSIM and the storage capacity determined through actual monitoring showed similar results, about 31 and 32 %, respectively, and the optimal capacity of rainwater facilities was calculated to be about 5,796,000-6,182,400 ton.

• The Journal of the Petrological Society of Korea
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• v.16 no.4
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• pp.208-216
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• 2007

Based on digital geologic and geomorphic maps of 1 : 250,000 scale, distributive ratios of rock types were obtained by ArcGIS 9.0 program in the Gyeonggi, Seoul and Incheon areas of the Gyeonggi province. In the Gyeonggi area, 37 rock types are developed, and their geologic ages can be classified into Precambrian, Age-unknown, Triassic, Jurassic, Cretaceous and Quatemary. Among them, distributive ratios are decreasing in the order of Jurassic Daebo granites, Precambrian banded gneiss of Gyeonggi gneiss complex and Quatemary alluvium, all of which comprise about 83.7% of the rock types in the area. In the Seoul and Incheon areas, 10 and 15 rock types are developed, respectively., with the firmer being classified into Precambrian, Jurassic and Quatemary, and the latter into Precambrian, Jurassic, Cretaceous and Quatemary. In the Seoul area, distributive ratios are decreasing in the order of banded gneiss of Gyeonggi gneiss complex, Daebo granites and alluvium, which consist of 95.5% of the rocks in the area. In the Incheon area, distributive ratios are decreasing in the order of alluvium, Daebo granites, banded gneiss of Gyeonggi gneiss complex, reclaimed land, and schists of Gyeonggi gneiss complex, which occupy about 96.2% of the rocks in the area. The ratio of alluvium in the Incheon area is greater than that of Gyeonggi and Seoul areas, and the ratio of reclaimed land in the Incheon area is greater that of the Seoul, which can be attributed to the recent reclamation of the land for the industrial results such as new town development along the coastline of the Gyeonggi Bay.

• Journal of Mushroom
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• v.2 no.1
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• pp.4-9
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• 2004

This study was carried out to investigate effect of NaCl treatment on growth oyster mushroom and Trichoderma spp. on PDA and in rice straws. We also investigated the possibility of oyster mushroom cultivation using rice straw harvested from the reclaimed land having been drained sea water. Mycelial growth of oyster mushroom was increased by treatment of 0.2% NaCl but decreased by treatment of the higher concentration of NaCl. In the case of the mycelial growth on PDA of Trichoderma spp., no change was found in 0.5%~1.0% NaCl, but decreased in the range of 1.0%~3.0% NaCl and drastically decreased at 5.0% NaCl. In the rice straws treated with different concentration of NaCl solution, mycelial growth of oyster mushroom showed almost same result compare to PDA. The spore formation of Trichoderma mould was almost same in both 0% and 0.3% NaCl, decreased in 0.5% and was not found spores in the higher concentration of NaCl. As increasing salt concentration in the rice straws, the NaO contents were increased. The $K_2O$ contents were decreased before and after sterilization. The moisture content of rice straws showed no difference by treatment of 3.0% NaCl but decreased the moisture by treatment of 5.0% NaCl. No pH change was found in the rice straws treated with NaCl. Mushroom yield in the rice straw of reclaimed land was a little higher than that of normal paddy land straw. The duration of primordium formation was not affected by NaCl concentration in rice straws. The yield of fruiting body in 0.3% NaCl treatment was 2,700kg, which was almost same to non-treated plot, but decreased in 0.5% NaCl. EC value of soaking water after submerging rice straw was higher than before, but NaO content was not changed at both condition.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.83-96
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• 2000

Erosional basins formed in middle and upper reaches of Korean great rivers have been main life space of local small and middle cities, but previous studies on erosional basins are widely apart from residents' life and are in shortage with the endeavor to elucidate the man and environment relationship. This paper analyzes the factors and the modes of land-use changes of hills in the erosional basin. In this paper four erosional basins with different geological conditions are selected to elucidate the effect of geological factor(Geochang: granite, Chogye: metamorphic rock, Angye: gravelly sedimentary rock, Maseong: limestone). And the distribution of land use on the transverse and longitudinal cross-section map of the hill is described. The landscape of erosional basin is consisted of surrounding mountains, hills, dissected valleys, and incoming river's floodplain. Dissected valleys and incoming river's floodplain were reclaimed early as paddy field and hills have been used as woodland up to recently. Residents have a new appreciation of hills as a productive hill out of a traditional holy space[mountain] by influence of capitalistic thought that 'natural environment is a sort of productive resource'. Population increase is the another pressure of hill reclamation. The modes of landscape changes due to natural conditions are as follow: (1) In Geochang basin with dense tectolineament spacing, the gentle part of hill is used as field, orchard and agricultural-industrial complex site and the steep part is as woodland. (2) Hills in Angye basin with sparse tectolineament spacing are relatively flat because of maintaining a part of original denudational surface, and are used as orchids, field, paddy fields and agricultural-industrial complex site. The dissection valleys between hills are gentle concave and are used as paddy fields. (3) Hills in Maseong basin are wide and flat, and are used as fields, orchards, and agricultural-industrial complex site. (4) Because hills in Chogye basin, a closed type, are weared by affluents and are narrow and short. Hills are used as woodland and wide dissected valleys are reclaimed as paddy fields.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.93-104
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• 2002

A field survey and experiment was conducted from 1996 to 1998 to develop rational technology for turfgrass vegetation of runway side of Incheon International Airport on the reclaimed tidal land in Young-Jong Island. Backfill of the experimental site was finished on August 1995. The experimental site was 8 ha located in the middle of the construction place for the main parking lot in front of the terminal building construction. The experimental field was drained by main open ditch, and divided three main plots, no subsurface tile drain, subsurface tile drain spacing with 22.5m, and with 45 m, respectively. The 17 sub plots were designed to test the effect of soil covering with red earth loam by 5 cm and 20 cm depth, application of chemical compound fertilizers and livestock manures, dressing of artifical soils and hydrophylic soil conditioners. The tested turfgrasses were three transplanting indigenous turfgrasses, Zoysia koreana, Zoysia sinica and Zoysia japonica, and two hydroseeding mixed exotic turgrasses, cool type I(tall fescue 30%, kentucky blue grass 40%, perenial ryegrass 30%), and cool type II(tall fescue 40%, perenial ryegrass 20%, fine fescue 20%, alkaligrass 20%). The soil backfilled with dredged seasand was sand textured with high salt concentration and low fertility. The soil showed high pH, low organic matter and low available phophate contents. The percolation rate was fast with high hydraulic conductivity. Desalinization was fast after installation of the main open drainage system. No subsurface tile drainage effect was found showing little difference in turfgrass growth. The covering and visual growth of turfgrasses were the best in the 20-cm soil covering with compound fertilizer treatment. The covering and visual growth of turfgrasses were satisfactory in the 5 cm soil covering with compound fertilizer treatment and with livestock manure treatments. The hydrophillic soil conditioner treatments were effective but expensive at present. The coverage and visual quality of turfgrasses were good for Zoysia koreana and Zoysia japonica. The coverages of turfgrasses by the hydroseeding with the mixed exotic turfgrasses were less than transplanting of native turfgrasses. In conclusion, for the runway side vegetation purposes, the subsurface tile drainage might not necessary as main open ditch drainage be sufficient due to fast percolation rate of the backfilled dredged seasand. The 5 cm soil covering with red earth might be sufficient for the runway side, but the 20 cm soil covering might be necessary for the runway side where high density of turfgrass coverage was necessary to protect from the airplance air blow.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.218-222
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• 2000

Wasted${\cdot}$rested mine areas give lots of effect on around-environmental changes after mining development. Leaching water at reclaimed land has been eluted from the solid components through physical, chemical, biological procedures by waters percolated through reclaimed site. The element analysis of waste tungsten ore tailing, leaching water analysis and removal of heavy metal by zeolite were performed to investigate the influent of acid rain on the released contents of H. M. The heavy metal contents in leaching water were determined to be As $1.21\;{\sim}\;1.54\;ppm$, Pb $0.11\;{\sim}\;0.15\;ppm$ and $SO_4\;^{2-}$ was $302\;{\sim}\;378ppm$. As deionized water and simulated acid rain (pH 3,4) were percolated through columns packed tungsten ore tailing, the amount of Mn, Na, Ca which were dissolved by pH4 solution was higher than those by distilled water. However, W and Mo were eluted easily by high pH solution. The change of heavy metal concentration by column experiment packed zeolite was effective a little because heavy metals were adsorved much more by zeolite.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.4
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• pp.627-635
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• 2016

Recently, several construction projects have been built to create residential area, industrial complex and agricultural land on reclaimed on- and offshore regions. Estimating the quantity of filling materials during reclamation is the most curcial factor of the total construction cost of reclamation project. However, the estimation of loss ratio, defined as the ratio of loss amount to overall dumped amount, mostly depends on the empirical methods and formulae based on the material characteristics due to the lack of sufficient literature about the loss ratio according to hydraulic conditions. In this studies the loss ratio of materials considering flow conditions and material characteristics were examined through hydraulic experiments. A series of hydraulic experiments was conducted using five different hydraulic conditions and two types of materials such as sand and anthracite in a horizontal rectangular flume ($13.0m{\times}5.0m{\times}0.10m$), in which a round type revetment was installed. It is found that the loss ratio generally tends to increase with increasing the particle Froude number regardless of the types of materials. Also, when the flow velocity(u) becomes higher than the critical flow velocity ($u_c$), the loss ratios of sand and anthracite are dramtically increased up to 7.4% and 24.4%, respectively. As a future work, more specific mean velocities will be considered to figure out the loss ratio and more accurate estimation of amount of filling materials will be possible to present with confidence.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.4
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• pp.247-262
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• 1979

Majority of reclaimable soils in hillside lands in Korea are red yellow soils, with exception in Jeju island, where most of reclaimable hillside lands are composed of volcanic ash soils. Songjeong, Yesan and Samgag series are the major soil series of red yellow soils which are available for the reclamation. When observed in the fields, they are distinguished as reddish brown clay loam, red yellow sand loam and yellowish brown sand loam. They have moderately good physical properties but their chemical properties are generally poor for crop cultivations. The chemical properties of red yellow soils, as compared to long time cultivated (matured) soils, are characterized by very low pH, high in exchangeable Al content and phosphorus fixation capacity. Also extraodinary low available phosphorus and organic matter contents are generally observed. On the other, the chemical properties of volcanic ash soils are characterized by high armophous Fe and Al hydroxides and organic matter contents, which are the causative factors for the extremely high phosphorus fixation capacity of the soils. The phosphorus fixation capacity of volcanic acid soils are as high as 5-10 times of that of red yellow soils. Poor growth of crops on newly reclaimed red yellow soils are mainly caused by very low available P and pH and high exchangeable Al. Relatively high P fixation capacity renders the failure of effective use of applied P when the amount of application is not sufficient. Applications of lime to remove the exchangeable Al and relatively large quantity of P to lower the P fixation capacity and to increase the available P are the major recommendations for the increased crop production on red yellow hillside soils. Generally recommendable amounts of lime and P to meet the aforementioned requirements, are 200-250kg/10a of lime and $30-35kg\;P_2O_5/10a$. Over doses of lime. frequently induces the K, B, arid Zn deficiencies and lowers the uptake of P. In volcanic ash soils, it is difficult to alter the exchangeable Al and the P fixation capacity by liming and P application. This may be due to the peculiarity of volcanic ash soil in chemical properties. Because of this feature, the amelioration of volcanic ash soils is not as easy as in the case of red yellow soils. Application of P as high as $100kg\;P_2O_5/10a$ is needed to bring forth the significant yield response in barley. Combined applications of appropriate levels of P, lime, and organic matter, accompanied by deep plowing, results in around doubling of the yields of various crops on newly reclaimed red yellow soils.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.301-308
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• 2008

We conducted the survey about the avian fauna, population, community and correlation between avian population and densities of the fallen rice grain in Cheonsu reclaimed area(Ganwol and Bunam Lake and reclaimed land) from Oct. 2006 to Mar. 2007. Total surveyed species number was 142 species, sum of maximum count of each species was 362,797 individuals, sum of average count of each species was 84,818 individuals. Comparing with early and late wintering season, number of species was stable in each survey time, but total population was decreased as the season progressed. Dominant species were Bean Geese Anser fabalis, Baikal Teals Anas formosa, White-fronted Geese Anser albifrons, Mallards Anas platyrhynchos and Pintails Anas acuta. Population fluctuation of the Bean Geese Anser fabalis, Baikal Teals Anas formosa, Mallards Anas platyrhynchos, PintailsAnas acuta was decreasing, but population of the White-fronted Geese Anser albifrons was stable. Number of species, total population were not significantly different among Ganwol, Bunam and Cheonsu Bay. Survey period was significantly correlated with species diversity and population in each area, and most community indices of each area were shown significant correlation. The density of the fallen rice grain was significantly different between the harvested rice paddy by big harvesting machine and small harvesting machine. Density of the fallen rice grain in stubble collected area was significantly different with area of stubble not collected. Density of the fallen rice grain was drastically decreased in the middle of wintering season, but not significantly different between Dec. 2006 and Feb. 2007. Avian population was strongly correlated with number of fallen rice grain in the same period.