• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.208-217
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• 2016

The Rural Development Administration moved to Jeonju for the balanced development of the land. This situation required establishment of new research fields with soils appropriate to cultivation. We applied a variety of amelioration techniques to mature soils of new research fields of the National Institute of Agricultural Science (NAS) and evaluated effects of the integrated amelioration techniques. The schedule of amelioration was following: 1) location of research fields was determined, 2) surface and subsoil samples were collected separately, 3) after aligning the top level of research fields, subsoil and surface soil were re-established with soil amendment, 4) the green manure crops were grown four seasons to improve the uniformity and increase the organic content of the research field, and 5) drainage canal and/or underdrainage were applied to poorly drained fields. The last green manure crop was rape in RDA fields and green barley in NAS fields. The average height, fresh weight, and dry matter weight of rape in good condition were 123 cm, $3,938kg\;10a^{-1}$, and $651kg\;10a^{-1}$, respectively. The height, fresh weight, and dry matter of green barley, on average, were 97 cm, $3,013kg\;10a^{-1}$, and $1,004kg\;10a^{-1}$, respectively. In the chemical properties of paddy field, pH and levels of silicate, calcium, magnesium, and potassium were in appropriate range but organic matter content of $16g\;kg^{-1}$ was less than the optimum level. In the chemical properties of upland field, pH and levels of phosphorus, calcium, magnesium, and potassium were appropriate range but organic matter content of $12g\;kg^{-1}$ was less than the optimum range. Evaluation of well-adapted soil was performed. The field in RDA was classified into the superior class with points ranging from 90 to 95 by the field evaluation test. The fields in NAS were mainly evaluated as the superior class with points greater than 85. However, some fields in NAS remained low quality with scores between 80 and 83. Further soil amelioration practices were suggested to fields with low soil quality.

• Journal of the Korean Society for Environmental Technology
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• v.19 no.6
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• pp.586-599
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• 2018

To learn about the discharge facility management of industrial complexes and the discharge characteristics of water pollutants in drainage, 11 sites were selected, including 16 discharge companies of Hanam Industrial Complex and High-Tech Scientific Industrial Complex and 4 drainages of the industrial complexes. Through the analysis, it was found that 12(75 %) of the 16 discharge companies had specific hazardous substances other than those registered at the time of installation and registration of the wastewater discharge facilities. In terms of other pollutants, 11 of the 16 companies(about 69 %) were found to have pollution items that differed from those included in approved and reported items lists. In addition, Formaldehyde, Mn, Zn, and Ba were discharged from 11 out of the 16 companies. Significantly, one of the specific hazardous water pollutants, Cu, was detected in all discharge facilities at levels from 0.029 to 0.929 mg/L. Even in major complexes drainages and the main stream of the Yeongsangang. As, Dichloromethane, and Chloroform were detected. However, it cannot be conclusively claimed that it is probable that these substances were actually discharged from the above facilities because research was only done in a limited range(Class 1 to Class 3), and therefore, further research is required. In the future, it will be necessary to expand the research scope of the discharge companies in order to establish a database of water pollutants, and to improve permits and reported items based on discharged substances.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.111-120
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• 2016

The objective of this study was to provide basic information for selecting the right timing and the right place of erosion control of stream on Gyeongsangnam-do. In order to achieve this objective, a total of 526 erosion control dams and 230 mountains stream conservation facilities on the constructed places and construction planned places for the erosion control were investigated on site, forest physiognomy, and hydrologic conditions. The erosion control dams and mountain stream conservation facilities were mostly constructed in the area, which has the sedimentary rock, 200-400m of altitude, a slope of 21~30°, and II of landslide hazard map. Among the forest environmental factors, it was only similar to the construction frequency in the areas that have small diameter class, III age class. Also, we investigated the hydrological environmental factors that determine the size and numbers of erosion control dam. The places constructed to the highest frequency were below 50ha in the area, 2.1~4.0km/㎢ of drainage density, longitudinal water system, 61~90mm of maximum precipitation per hour, and 201~300mm of day maximum precipitation. As the results, the sites and floodgate conditions between the constructed places and stream conservation facilities for the erosion control showed to be very similar. Therefore, these results indicate that the erosion control of the stream of the areas, which have the disruption of mountain peaks and the high erosion risk areas, should be used on both the erosion control dam and stream conservation facilities.

• Journal of Chest Surgery
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• v.32 no.6
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• pp.510-517
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• 1999

Background: Total anomalous pulmonary venous connection (TAPVC) is still one of the more challenging congenital heart defects in newborns and young infants. The purpose of the study is to evaluate the early and midterm results of the surgical corrections for patients in early infancy with isolated TAPVC. Material and Method: Hospital records of 15 consecutive patients in early infancy (January 1993 to August 1998) were retrospectively reviewed. There were 8 boys and 7 girls whose ages ranged from 4 days to 3.5 months (median age 22 days). Their body weight ranged from 1.75 kg to 4.9 kg (mean 3.54 kg). The abnormal anatomical connections were supracardiac in 11, cardiac in 3, and infracardiac in 1. In 6 patients (40%), the pulmonary venous drainage was obstructive. Total circulatory arrest was used in 13 patients. Anastomosis between the common pulmonary vein and the left atrium was performed with a continuous suture technique using a fine nonabsorbable polypropylene suture through a lateral approach behind the right atrium. Result: There was one hospital death (6.5%) caused by a sepsis 17 days after the operation in a neonate who had supracardiac drainage and was dependent on a ventilator preoperatively. There were 2 late deaths. One died sudde`nly of an unknown cause at home 2.5 years after the operation and the other died of a recurrent pulmonary hypertension 3 months after the reoperation due to pulmonary venous obstruction (PVO). Two patients required reoperations because of PVO 5 months and 10 months respectively after the initial operation. Of these patients, one patient is alive at the present time with persistent pulmonary hypertension. All survivors without postoperative PVO (78.6%) were in NYHA functional class I at mean follow-up of 25.8 months (0.5∼67 months). Conclusion: Surgical correction of TAPVC in early infancy can be performed at low risk. However, there were 2 postoperative PVOs (14.3%) which had bad results. The survivors without postoperative PVO had excellent functional status.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.309-315
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• 2009

Maintenance of adequate soil water content during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement for precision irrigation would allow efficient supply of water to crops, thereby resulting in minimization of water drainage and contamination of ground water. This research reports on the characterization of spatial and temporal variations in water contents through three different textured soils, such as loam, sandy loam, and loamy sand, when water is applied on the soil surface using an one-line drip irrigation system and the soils are dried after the irrigation stops, respectively. Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30cm depths. Spatial variability in water content for each soil type was strongly influenced by soil textural class. There were big differences in wetting pattern and the rate of downward movement between loam and sandy loam soils, showing that the loam soil had a wider wetting pattern and a slower rate of downward movement than did the sandy loam soil. The wetting pattern in loamy sand soil was not apparent due to a low variability in water content (< 10%) by a lower-water holding capacity as compared to those measured in the loam and sandy loam soils, implying that the rate of water drainage below a depth of 30cm was high. When soils were dried, there were highly exponential relationships between water content and time elapsed after irrigation stops ($r^2$${\geq}$0.98). It was estimated that equilibrium moisture contents for loam, sandy loam, and loamy sand soils would be 17.6%, 6.2%, and 4.2%, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.696-704
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• 2010

The objective of this study was analysis of two methods of land suitability classification for wild edible green. One method was Maximum limiting factor method (MLFM) and the other was Multi-regression method (MRM) for land suitability classification for wild edible green. The investigation was carried out in Pyeongchang, Hongcheong, Hoeingseong, and Yanggu regions in Korea. The obtained results showed that factors related to the decision classification of the land suitability for wild edible green cultivation were land slope, altitude, soil morphology and gravel contents so on. The classification of the best suitability soil for wild edible greens were fine loamy (silty), valley or fan of soil morphology, well drainage class, B-slope (2~7%), available soil depth deeper than 100cm, and altitude higher than 501m. Contribution of soil that influence to crop yields using Multi-regression method were slope 0.30, altitude 0.22, soil morphology 0.13, drainage classes 0.09, available soil depth 0.07, and soil texture 0.01 orders. Using MLFM, area of best suitable land was 0.2%, suitable soil 15.0%, possible soil 16.7%, and low productive soil 68.0% in Hongcheon region of Gangwon province. But, area of best suitable land was 35.1%, suitable soil 30.7%, possible soil 10.3%, and low productive soil 23.9% by MRM. There was big difference of suitable soil area between two methods (MLFM and MRM). When decision classificatin of the land suitability for wild edible green cultivation should consider enough analysis methods. Furthermore, to establishment of land suitability classification for crop would be better use MRM than MLFM.

• Journal of Korean Society of Forest Science
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• v.47 no.1
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• pp.52-61
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• 1980

This study is carried out to learn the properties of forest soils in Korea and propose the reasonable management methods of forest land. Among 178 soil series surveyed until now in Korea forest soils include 64 series broken down according to the weathered products into 5 categories such as residual materials on mountain and hill, residual materials on rolling and hill, colluvial materials on local valley and fans, alluvial materials and volcanic ash soils. What discussed in this paper are classification system, parent rocks, texture class and drainage conditions of Korean forest soils. The characteristics of Korean forest soil properties classified in U.S.D.A. soil classification system are as follows: 1. Residual soils on mountain and hill (29 soil series) are almost Lithosols without any distinct soil profile development. They have loamy skeletal (11 series), coarse loamy (5 series), fine loamy (3 series), and fine clayey soils (3 series). Their drainage conditions are somewhat excessively drained in 16 series and well drained in 7 series. 2. Residual soils on rolling and hill (19 series) are Red-Yellow Podzolic soils with well developed soil profiles. They have coarse and fine loamy texture in 12 series and fine clayey texture in 5 series mostly with well drained condition. 3. Colluvial soils on local valley and fans (13 series) include mostly Regosols and some Red-Yellow Podzolic Soils and Acid Brown Forest Soils. They have loamy skeletal (4 series), coarse loamy (3 series), fine loamy (3 series), and fine clayey soils (2 series) with well drained condition. 4. Soil textures of weathered products of parent rocks are as follows: 1) Parent rocks producing coarse texture soils are rhyolite, granite gneiss, schist, shale, sandstone, siltstone, and conglomerate. 2) Parent rocks producing fine and heavy texture soils are limestone, basalt, gabbro, and andesite porphyry. 3) Granite is a parent rock producing various textured soils.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.6
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• pp.419-424
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• 2008

Objective of this study was to evaluate the adaptation and the soil conservation effect of improved wild vine in sloped upland of highland about 600m from sea level in Korea. A mainly producing district of the improved wild vine in Korea was distributed 230m to 540m from sea level, and its rainfall ranged 1,200 to 1,700 mm. The lowest temperature was from -19.6 to $-25.4^{\circ}C$. Their soil texture was from sandy loam to clay loam, where drainage class was well drained and the contents of soil organic matter and total nitrogen in the improved wild vine's cultivation area were higher than those of Chinese cabbage's cultivation area in the highland. According to improved wild vine's cultivation methods, the amounts of soil erosion were 25.5,4.1, and $1.8MT\;ha^{-1}$ in clean culture, part sod + mulching, and nature sod, respectively. Those were below 30 to $80MT\;ha^{-1}$ of sloped upland at highland in Korea. The result suggests that it is possible to cultivate the improved wild vine over wintering at 600m of highland above the sea level. We can substitute the improved wild vine for Chinese cabbage in the highland for soil conservation.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.81-92
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• 2017

Recently, agricultural lands have decreased sharply, which was caused by huge housing site, urbanization, land consolidation, and road construction etc. In particular, Yangju city near Seoul city has the most severe land use change in Korea. Therefore, we analyzed changes of land use, soil properties, and soil information in order to provide the basic soil information and soil management practices in this city. The area of crop cultivated land in Korea (2015) reduced by 12,090 ha compared to ones from the previous year (2014). The paddy field decreased by 25,421 ha but, upland field increased by 13,331 ha. One of the reasons for the reduction of the paddy field was converting paddy field to upland (20,916 ha) > others (3,056) > building (2,571) > public facilities (847) > idle land (217). But, reasons for increase of upland field were switching paddy to upland (20,916 ha) > land developed (634). The main reason of converting paddy field to upland was changing from rice to more profitable speciality crops or pulses. The cropland area (paddy fields, upland, orchard) of Yangju city reduced by 1,412 ha (2015/2014). The ratio of cropland area in each city reduced by 22.9% dramatically compared 2015 to 1999. The paddy fields located in alluvial plains in Yangju city were changed into upland or green house. The drainage classes of soil have been deteriorated because the flows of water were intercepted by road construction and other disturbance to water flows. In particular, paddy fields have been changed to not only upland, orchard, greenhouse cultivation but also to fallow and soil dressing on paddy in Yangju city. To analyze result of soil survey of Yangju city, 858 soil codes (soil phases) were used and the area was 105.17ha. The number of soil series increased from 60 to 65, and that of soil phase increased from 105 to 124. The largest increased area was Noegog soil series. 125.7ha of Neogog soil series was incorporated from the existing Sachon, Yecheon and Eungog soil series. The soil suitability class of paddy field in Ogjung huge housing site of Yangju city was the 4th grade for 32.6% of the area. The soil suitability classes of upland were 2nd and 3rd grade for 72.4% of the area. Farm land with high quality should be conserved by related law.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.17-24
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• 2016

At present, summer cloudburst and local torrential rainfalls have increased in this country, because of climatic change. Therefore, studies on prevention of soil loss have been actively proceeded, and Korea Forest Service has offered landslide hazard map. Landslide hazard map divides risks into 5 classes, by giving weight with 9 kinds of elements. In August 25 2014, soil loss occurred in the whole Oryun Tunnel, Geumjeong-gu, Busan, because of local torrential heavy rain. As a result of comparing with landslide hazard map, the area where soil loss occurred in reality is a safety zone on hazard map. Rainfall, soil map, geological map, forest type map, gradient, drainage network, watershed, basin shape, and efflux of the whole Oryun Tunnel where soil loss occurred were analyzed. As a result of an analysis, it is judged that soil, forest type, much efflux and peak discharge, degree of water network and basin shape of a place where landslide occurred are causes of soil loss. It is judged that efflux, peak discharge, and basin shape by the localized rainfall that is not considered in landslide hazard map of them are the biggest causes of soil loss. It is judged that efflux, peak discharge, degree of water network and basin shape by the rainfall are important through a study on a causual analysis on soil loss in the whole Oryun Tunnel where is one of occurrence area where a lot of propertywere lost by the record local torrential rainfalls. A localized torrential downpour should be prepared by considering these elements on judgement of a landslide hazard area.