• Weed & Turfgrass Science
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• v.7 no.1
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• pp.15-21
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• 2018

Since sulfonylurea (SU) herbicide-resistant Monochoria korsakowii in Seosan reclaimed land in 1998 was reported first, herbicide-resistant weed species and their area of occurrence have been steadily increasing. In recent years, Sagittaria trifolia resistant to SU herbicides has been reported in Gimhae, Gyeongnam province. While collecting S. trifolia for constructing barcode database of major weeds we were suspicious by the continuous variation in the leave morphology of the species. In order to identify the S. trifolia from S. aginash we barcoded the species collected from domestic using ITS and compared the sequence variation with the ITS sequences of S. aginash downloaded from NCBI. As a result, it was found that the plants collected from the domestic did not have any variation among individuals although they showed wide morphological variation. On the other hand, interspecific variation between S. trifolia and S. aginash was 4.6%. Plants that are difficult to identify using morphological characters can be identified quickly and accurately using the barcode technique. Herbicide-resistant weeds may require different management practices depending on the species even in the same genus. Domestic herbicide-resistant weeds are steadily increasing. Therefore, accurate identification of these species must be preceded for effective weed control.

• Journal of Environmental Science International
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• v.21 no.2
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• pp.181-188
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• 2012

Salicornia europaea (glasswort) is succulent, annual, halophytic plant mainly distributed throughout reclaimed land or salt marsh. It has strong tolerance to salt so that it plays the part of the pioneer species in the first succession. According to domestic and foreign studies, S. europaea contains plenty of minerals and antioxidant in the body. Since people take note of an availableness of this plant as health diet, the natural growth sites are threatened. In addition to development of salt marsh and sea shore, imprudent harvest has a bad effect to S. europaea population maintenance. To seek ways to preserve the population of this plant, we carried out the continuity of seed germination and restoration test. Seokmo Island, Daebu Island, Youngjong Island and Sudokwon landfill in Korea are selected sites for research. Result of germination continuity shows that most S. europaea seeds germinate on March but no more after July. However the germination was occurred after that time in the greenhouse. So we concluded that no germination after July is a matter of environmental condition not the number of remaining seeds. Also germination was seldom occurred in the spot where seeds production was not happened. In result of continuity test of seed germination by soil depth, germination was occurred vigorously only in top soil. From these results, we note that most S. europaea germinate in the early spring, and germination is finished by July. And this rapid germination speed makes the number of seeds in soil seed bank rare. If a large number of S. europaea in some area are harvested after July, the number of this species will dramatically decrease in that area the following year. In Seokmo Island, we carried out reintroduction experiment by sowing S. europaea seeds. On the first year, a small number of S. europaea settled and they produced seeds successfully. On April 2010, the second year, we observed many S. europaea in seed sowing sites. And we found out that plowing is more efficient than treatment sea water for settlement of S. europaea.

• Journal of the Korean GEO-environmental Society
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• v.10 no.3
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• pp.21-28
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• 2009

As the natural aggregates such as sand and clay are getting exhausted, the quantity of utilizing geosynthetics is being increased in the solid waste landfill. Especially, the waste landfills have been constructed at the gorge in the mountainous area and reclaimed land from the sea in the Korean Peninsula. Those areas are not favorable for construction of waste landfill in geotechnical engineering aspect. In this study, the frictional characteristics of geosynthetics that used in the waste landfill were estimated. Then, the studies of the behavior of geosynthetics and stability of LDCRS (Leachate Detection, Collection, and Removal System) of side slope were conducted in the waste landfill by means of the pilot test, and numerical analysis. Geocomposite which is combined type or separated type is influenced on the strain itself, and also implicated in the stress and strain of geomembrane at the lower layer. The strain on the combined type of geocomposite is about 50% smaller than that of the separated type at the side slope. The lateral displacement and settlement of top at the slope with the separated type are three times greater than that of the combined type. In the numerical analysis, discontinuous plans in between ground and geosynthetic, geosynthetic and geosynthetic, goesynthetic and waste have been modeled with the interface element. The results gave a good agreement with the field large-scale model test. The relative displacements of geosynthetics were also investigated and hence the interface modeling of liner system is appropriate for analysis of geosynthetics liner system in the waste landfill.

• Journal of Navigation and Port Research
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• v.28 no.3
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• pp.269-276
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• 2004

The reclaimed land has peculiar characteristic of nature environment unlike midtown or inland and also, in comparison with inland, has bad weather condition, such as low temperature, strong wind, excessive sunshine, and moisture involved in a salt. Therefore the case of developing water front needs understanding characteristic of weather environment mused by reclamation in detail and proper development and organized maintenance. If development which doesn't investigate topographic and climate characteristic sufficiently is drove ahead, a rise of expense for energy and maintenance is going to be mused by deteriorating weather environmental, occurring a flaw of facility and calculating inaccurate capacity of facility. We looked into the weather state and drew up the standard weather data of the newport area in Busan which is reclaiming and developing now. In this research at the base qf the standard weather data, we calculate the dynamic peak loads for commerce, business and residence and then we utilize the results of the load calculation as basic information to determine facility capacity in the rear city of the newport area.

• Journal of the Korea Concrete Institute
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• v.15 no.6
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• pp.840-847
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• 2003

Recently, the coal-ash production has been increased by increase of consumption of electric power. So it is important to secure a reclaimed land and treatment utility for coal-ash. This is an experimental study to compare and analyze the engineering properties of concrete according to W/C and replacement ratio of bottom ash. For this purpose, the mix proportions of concrete according to W/C(40, 50, 60%) and replacement ratio of bottom ash(0, 10, 20, 35, 50%) were established, and then tested for slump, chloride content, setting time, bleeding content, compressive strength. Also the durability test of concrete with W/E 60% was performed. According to test results, it was found that the bleeding content of concrete decreased as the replacement ratio of bottom ash increased. And the chloride content of concrete using the bottom ash increased as the replacement ratio of bottom ash increased, but it is satisfied with the chloride content of fresh concrete $0.30kg/m^3$ below("concrete standard specification" regulation value). The compressive strength of concrete using the bottom ash was similar to that of BA0 concrete after 28 days of curing and the carbonation depth of concrete was increased according to increase of the replacement ratio of bottom ash.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.415-420
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• 2014

Toxoplasmosis is an important cause of foodborne, inflammatory illnesses, as well as congenital abnormalities. Currently available therapies are ineffective for persistent chronic disease and congenital toxoplasmosis or have severe side effects which may result in life-threatening complications. There is an urgent need for safe and effective therapies to eliminate or treat this cosmopolitan infectious disease. The aim of this study was to investigate the in vitro anti-Toxoplasma activities of Suaeda maritime, one of the halophytes, using tachyzoit of T. gondii RH strain infected HeLa cells. As the results, the selectivity of Suaeda maritime extract was 6.63, which was higher than Sulfadiazine selectivity (2.06). Also, we perfomed the cell proliferation inhibition test and the morphological study to evaluate the anti-T. gondii activity of Suaeda maritime extract with HeLa cells. As the results, the inhibition rate of the Suaeda maritime extract was high inhibition rate. This indicates that the Suaeda maritime extract may be used for new anti-T. gondii agent.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.129-134
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• 1997

Effect of soil moisture level on the growth of ginger plant was investigated through a pot experiment. The soil used for this study was collected from a newly reclaimed hillside land. The soil was a silty clay loam(19% sand, 57% of silt and 24% of clay), acidic in soil rection(pH 4.7, in $H_2O$) and low in organic matter content(1.2%). Soil moisture levels selected for the experiment were 10, 15, 20, 25, and 30% on weight basis. Under the soil moisture of 20-25%, the emergence ratio was 80-100%, 25 days alter planting. The performance of above ground parts was best under 20-25% of soil moisture. When the soil moisture content was far from 25%, high or low, the die out of above ground parts of ginger tended to increase. Under 20-25% of soil moisture the growth of roots was best and the occurrence of root rot was minimal.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.12
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• pp.37-41
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• 1972

This study has been conducted to estimate the proper amount of phosphatic fertilizer required to increase-yield in growing soybeans on newly reclaimed-sterile land which is short of phosphatic fertilizer. IKSAN, the variety chosen for this study, was planted, using the plant spacing $60cm{\times}30cm$. Phosphatic fertilizer was applied in 4 levels in none, standard, double, and triple amount. and at the same time, nitrogen and postassium were applied only in standard amount. Randomized block design was applied in arranging the experimental plots. A series of results acquired are summarized as follows. 1. The fact was recognized that only the standard amount of phosphatic fertilizer is effective for increasing the pod numbers and the soybean yield per l0a. 2. The difference in stem length and stem diameter was very remarkable even among individual plants in the same plot, Throughout all four of the plots there were difference in stem length and stem diameter. That is to say, any invariable tendency on them due to the amount of phosphatic fertilizer applied could not be observed at all. 3. It was recognized that amount of phosphatic fertilizer applied did not have a considerable influence upon the weight of the seeds and the number of seeds contained in 0.l8ι. 4. It was observed that the weight of 1000 seeds was strikingly increased as far as double the amount phosphatic fertilizer.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.1-11
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• 2015

This research was conducted to compare the effect of soil amendment and loess on physial and chemical properties of dredged soil and primary height growth of Ulmus davidiana var. japonica. Three types of research plots: control plot (Dredged soil only), DC treatment plot (Dredged soil + soil amendment) and DCL treatment plot (Dredged soil + soil amendment + Loess) were set at Okgu research site in Saemanguem. 32 trees of U. davidiana var. japonica were planted in each plots after 14 months from the construction. Soil texture, pH, electrical conductivity (EC), organic matter (OM), total nitrogen (TN), available P, exchangeable cation ($K^+$, $Na^+$, $Mg^{2+}$, $Ca^{2+}$) and sodium chloride were measured after 3 years from the construction. Also, survival rate and height of U. davidiana var. japonica were measured 22 months after planting, and the correlation between height of trees and the physico-chemical properties of soil were analyzed. Even though pH in both DC and DCL treatment plots are lower than control plot, they are still alkaline (> pH 8). OM, TN and available P in both DC and DCL treatment were higher than the control. Particularly, the content of available P in both DC and DCL treatment plots are 1.4~5.1 times and 2.0~3.1 times higher than the control respectively. The concentration of exchangeable Mg in DCL treatment plot was 1.1~5.5 times higher than the control (p < .05). The survival rate of the species was the highest in DCL treatment plot (98%) followed by DC treatment plot and the control. The average height of the trees in both DC and DCL treatment plots is 1.1m while the control is 0.8m. OM, TN, available P, K+ were significantly related to the height of U. davidiana var. japonica(p < .01). The results indicate that soil amendment affects on soil physial and chemical properties of dredged soil and height growth of U. davidiana var. japonica.

• Research in Plant Disease
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• v.17 no.1
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• pp.90-94
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• 2011

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is a very serious disease in rice growing regions of the world. There are no effective ways of protecting rice from the disease. In this study, the bacteriophage (phage) mixtures infecting Xoo were investigated as biological control agent on BLB. The effects of pH, heat and ultraviolet on the stability of phages were investigated to check and increase the possibility of practical use in the field. Phages were rather stable between pH 5 and pH 10. The infectivity dropped sharply when the phages were incubated at $50^{\circ}C$ and more than 90% of the phages were inactivated after two minutes of ultraviolet treatment. The phages were stable for 7 days at the rice plant leaves, and the phages survived 10 times more than other treatments when mixed with skim milk. Although the skim milk increased the stability of the phages, the control efficacy was not effective. However, the phage mixtures reduced the occurrence of BLB when they were treated with Tecloftalam WP or Acibenzolar-S-methyl simultaneously. The results indicated that the Xoo phages could be used as an alternative control method to increase the control efficacy and reduce the use of agrochemicals.