• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.3
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• pp.214-221
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• 2020

Salinity is one of the major abiotic stressors that inhibits the growth, yield, and productivity of crop plants. Therefore, it is necessary to develop crops with increased salt tolerance for cultivation in saline soils such as is found in reclaimed land. The objective of this study was to develop a salt-tolerant silage rice line that grows on reclaimed land. In order to develop this salt-tolerant silage rice, we transferred Saltol, a major QTL associated with salt tolerance, from IR64-Saltol, a salt-tolerant indica variety, into Mogyang, a susceptible elite japonica variety. To determine the effect of salt stress, Mogyang and IR64-Saltol cultivars were grown on a medium containing various concentrations of NaCl in in vitro conditions. Shoot length was found to decrease with increasing salt concentrations, and root growth was almost arrested at NaCl concentrations over 50 mM in the Mogyang cultivar. Based on these preliminary results, we screened five salt-tolerant lines showing superior growth under salt stress conditions. Polymerase chain reaction and sequencing results showed that the introgression types of Saltol QTL were derived from the IR64-Saltol cultivar in almost all selected lines. Based on the observed growth and physiological characteristics, the new Saltol introgression lines showed higher salt tolerance compared to the Mogyang parental cultivar. The salt-tolerant lines identified in this study could be used as a genetic resource to improve rice salt tolerance.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.495-503
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• 1992

The internal and external outputs of the agricultural sub-systems of mixed livestock-crop farms in Pabna Bangladesh were analysed, to clarify the multiple functions of cattle in farm systems. Production systems with grazing areas were relatively more productive than those with no grazing. There was a tremendous variation in farm income, largely because of land area. An increase of one ha in land area was estimated to boost farm income by about 50%. Number of cattle, cattle off-take percentage and milk off-take per average cow related positively to farm income. As land area decreased the relative importance of cattle production increased. Crops were dominant in producing food for home consumption. Cattle contributed only 5-6 per cent to home consumption. Cattle supplied a significant cash income: 45 per cent in the villages with grazing areas and 57 per cent in the other villages. In future, the cash output from cattle will decline and emphasis will shift to the role of cattle in supporting crop production. Any research or development strategy for livestock needs to focus first on the importance of the complex relation between livestock and crops.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.37-41
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• 1977

Zeolite was applied of the tidal land and its effect on growth and yield of the two rice varieties, Yushin and Jinheung, was studied. The salinity of the zeolite treated soil was lower than that of the control. The effect of zeolite on growth of rice was appeared at the maximum tillering stage. The remarkable effect of zeolite on grain yield appeared in the variety Yushin, an indiea type. The amount of 600kg/10a was recognized to be an optimum amountd of the zeolite application in the tidal land.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.139-142
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• 2000

The experiment was carried out to study the variations and geographical distribution of $\beta$-amylase isozyme by isoelectric focusing (IEF) within Korean, Chinese and Japanese soybean land races. In pH 3-10 gel of IEF, the amylase of soybean accessions was separated into low pI group isozymes (TEX>${$Sp_1$}^b$) and high pI group isozymes(${$Sp_1$}^a$). In pH4-6.5 gel, isoelectric points were at 5.07, 5.15, 5.25, 5.40, and 5.94, and h, j, and k bands also were found. The distribution of Sp$_1$$^{a}$ allele (high pI type) was 29.3% in soybean accessions from Korea, 10.1 % in those from China, and 6.9% in Japanese accessions. The percentage of ${$Sp_1$}^a$) allele was the highest in soybean accessions from Kyungsang province (35 %) in Korea, then central China (32 %) in China, and Honshu (10%) in Japan.

• Journal of Soil and Groundwater Environment
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• v.15 no.5
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• pp.16-22
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• 2010

Heavy metals in soils exist in various forms dependent upon surrounding conditions. As the Janghang smelter area is of concern for its high elevated heavy metal concentrations, Korean government decided to remediate the area. Main objectives of this research were; to analyze heavy metal concentrations and their existing forms in the vicinity of the smelter; and to understand differences made by analysis techniques of heavy metals. Top soils of rice field, crop field, bare field, and forestry in the area were sampled and analyzed for their physicochemical characteristics. Concentrations of Cu, Cd, Pb, and As were analyzed with two pretreatment techniques adopted using 0.1 N HCl and aqua regia. To analyze existing forms of heavy metals, Tessier's schemes for sequential extraction technique were adopted. Exchangeable fraction and carbonate bound fraction of heavy metals may pose potential threat to environment and were in the order of Pb > As > Cu > Cd. If assessing mobile fraction of heavy metals by land uses, the order was forestry > bare land > crop field > rice field. When analyzed using Tessier's scheme, high ratio of residual fractions to total arsenic concentration should be considered for remediation design of the area.

• Journal of the Korean association of regional geographers
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• v.10 no.2
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• pp.479-496
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• 2004

This study attempts to examine Egyptian agricultural development with regard to the social and political changes in the Egypt, and tries to explore the patterns of major crops and those spatial distribution nowadays. Also, land reclamation processes and farming activities are explained. Agricultural development in Egypt has been considerably affected by historical international trade, and those crops such as cotton and sugar cane have been especially protected and controlled as strategic crops by the Egyptian governments. The issues of land ownership have been varied with political environments by periods, but the controls to the strategic crops have been consistently maintained to a degree though some variations. since the 1990s, national liberalization programs also caused to change the agricultural policies which have affected the adjustments of crop production and land use. Spatial distribution of major crops and farming activities are examined in relation to natural environments by Delta, Middle and Upper Egypt, desert areas. The projects of land reclamation after 1952 are evaluated with the effects of government intervention, and the actors in use of the reclaimed lands are investigated.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.583-590
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• 2012

This study proposes fusion image matching method according to land cover property to generate a detailed DEM using the high resolution IKONOS-2 stereo pair. A classified image, consists of building, crop-land, forest, road and shadow-water, is produced by color image with four bands. Edges and points are also extracted from panchromatic image. Matching is performed by the cross-correlation computing after five classes are automatically selected in a reference image. In each of building class, crop-land class, forest class and road class, matching was performed by the grid and edge, only grid, only grid, grid and point, respectively. Shadow-water class was excepted in the matching because this area causes excessive error of the DEM. As the results, edge line, building and residential area could be expressed more dense than DEM by the conventional method.

• Proceedings of the Korean Society of Crop Science Conference
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• 1998.10a
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• pp.134-158
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• 1998

The objectives of this article are to identify the current status of agricultural infrastructure in North Korea and to suggest some cooperation measures among South and North Koreas and international agencies in order to develop the North Korea's agricultural infrastructure. The area of cultivated land in North Korea is 1,992 thousand ha (paddy field: 585 thousand ha: upland: 1,407 thousand ha) in 1997. Major water use facilities in North Korea are 1,900 reservoirs (included 100 big dams), 36,400 irrigation pumping stations, 1,600 drainage pumping stations, and 14'a,000 wells. In addition, there is 'two thousand Ri canal construction project' linking the rivers of Aprok, Daeryong, Daedong, Jaeryong, and Yesong. The unit of paddy land consolidation is about 1 ha which is regarded as rational for agricultural mechanization. The project of 'Darak' upland construction to create small size farmland, which has been carried out since 1976 has been unsuccessful due to the shortage of construction equipment. The area of farmland created by reclamation by 1995 is only 75 thousand ha although the potential project area is at)out 320 thousand ha along the western coast. It is due to the fact that civil engineering technologies and equipments are old and investment funds are insufficient. These are a few suggested areas of cooperation among South and North Korea and international agencies in order to improve North Korea's agricultural infrastructure : i) see land reclamation and land consolidation projects to increase paddy fields for rice production; ii) rehabilitation project in farm land areas devastated by flood; and iii) agricultural water development project which including diagnosing and rehabilitating irrigation and drainage facilities.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.3
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• pp.75-88
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• 2016

In this study, we used the CLUE-s model to predict the future land-use change based on the urban growth scenario in South Korea. The land-use maps of six classes (water, urban, rice paddy, upland crop, forest, and grass) for the year 2008 were obtained from the Ministry of Environment (MOE), and the land-use data for 5-year intervals between 1980 and 2010 were obtained from the Water Resources Management Information System (WAMIS), South Korea. For predicting the future land-use change, the MOE environmental conservation value assessment map (ECVAM) was considered for identifying the development-restricted areas, and various driving factors as location characteristics were prepared for the model. The predicted results were verified by comparing them with the land-use statistics of urban areas in each province for the year 2008. The prediction error rates were 9.47% in Gyeonggi, 9.96% in Gangwon, 10.63% in Chungbuk, 7.53% in Chungnam, 9.48% in Jeonbuk, 6.92% in Jeonnam, 2.50% in Gyeongbuk, and 8.09% in Gyeongnam. The sources of error might come from the gaps between the development of political decisions in reality with spatio-temporal variation and the mathematical model for urban growth rate in CLUE-s model for future scenarios. Based on the land-use scenario in 2008, the land-use predictions for the year 2100 showed that the urban area increased by 28.24%, and the rice paddy, upland crop, and forest areas decreased by 8.27, 6.72, and 1.66%, respectively, in South Korea.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.1
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• pp.3627-3641
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• 1975

The Government is trying to increase total food grain yield to meet national self sufficiency by means of increasing unit yield as well as extending crop land, and this year he set the target of 321,000 hectare of forest to clear for cropping. This study was carried to investigate the most efficient method of clearing hillock by bulldozer, and successful method to develope yielding potential of newly cleared land in short term. Since the conventional land clearing method is just earth leveling and root removing neglecting top soil treatment, the growth of crop was poor and farmer tends not to care the land. The top-soil-furrowing method is applied through out this study, that is advantageous especially for the land having shallow top soil and low fertility like Korean forest. In this study, various operating method were tried to find out most efficient method separately in connection with the land slope less than 25 percent and over, and several fertilizing methods to develop yielding potential. The results are as follows; 1) For the natural land slope utilization method, applicable to the land having less than 25 percent slope, reverse operating was more efficient than using forward gear of bulldozer. The operating time was 3 hour 32 minutes and 36 seconds using forward gear was 2 hour 32 minutes and 30 seconds for reverse gear operation per 1,000 square meter. 2) Bulldozer having angle blade adjustment needed 7hr 15min. for constructing of terrace per 10a compaire with the one having angle & tilt adjustment needed 6hr 4min for same operations. Specially there is significant difference for operation time of first period (earth cutting) such as bulldozer having angle blade adjustment needed 3hr 56min compaired with the one having angle & tilt adjustment 3hr 59min. In construction of terrace, the bull-dozer having tilting and angle blade adjustment was most suitable and performed efficiently. 3) For the fertilizer application treatment, the grass (Ladino clover) yield in first year was almost same as ordinary field's in the plot applied(N.P.K+lime+manure) while none fertilizer plot showed one tenth of it, and (N.P.K.+lime) applied plot yielded on third. 4) The effect of different land clearing method to yield showed significant difference between each treatment especially in the first year, and the conventional method was the lowest. In the second year, still conventional terracing plot yielded only half of ordinary field while the other plots showed as same as ordinary field's. 5) The downward top soil treatment plot showed most rapid improvement in soil structure during one year physio chemically, it showed increase in pH rate and organic composition, and the soil changed gradually from loam to sand-loam and the moisture content increased against the pF rate, and it gives good condition to grow hay due to the increase of field water capacity with higher available water content. 6) Since the soil of tested area was granite, the rate of soil errosion was increased about 2 to 5 percent influencing in soil structure more sand reducing clay content, and an optimum contour farming method should be prepared as a counter measure of errosion.