• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.1
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• pp.47-53
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• 2011

From 12 to 16 July 2006, 4 days' torrential rainfall in Deoksan-ri, Inje-up, Inje-gun, Gangwon-do caused massive landslide and debris flow. Huge losses of both life and property, including two people buried to death in submerged houses, resulted from this disaster. As the affected region is mostly mountainous, it was difficult to approach the region and to estimate the exact extent of damage. But using aerial photographs, we can define the region and assess the damage quickly and accurately. In this study the debris flow region in inje, Gangwon-do was analyzed using aerial photographs. This region was divided into three sections - beginning section, flow section and sedimentation section. Informations for each section were extracted by digitizing the shot images with visual reading. Topographic, forest physiognomic and soil characteristics and debris flow occurrences of this region were analyzed by overlaying topographic map, forest type map and soil map using GIS. Comprehensive analysis shows that landslide begins at slope of about $36^{\circ}$, flows down at $26^{\circ}$ slope, and at $21^{\circ}$ slope it stops flowing and deposits. Among forest physiognomic factors, species of trees showd significant relationship with debris flow. And among soil factors, effective soil depth, soil erosion class, and parent materials showed meaningful relationship with debris flow.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.93-99
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• 1985

All soil characteristics for 10,077ha of establishable grassland in 1984 were statistically summarized. Soils could be classified into 5 of Order, 7 Suborder, 11 Great group, 28 Subgroup, and 105 Series by the new comprehensive classification system. Distribution rate of farm houses managed the extent magnitude of 3.0ha was 70.8% and its total extent was 35.9%. Extent rate of uncultivated method was 71.3%. These soils were distributed with regard to hilly land and mountain foot slope at, 82.0, and to 0-30% slope at 66.9%. Soil texture was light such as sandy loam to loam at 85.0%, available soil depth more than 20cm at 97.8%, and gravel content less than 35% at 98.4%. Soil would be distributed in 67.3 of first class, 29.7 second class, and 3.0% third class for suitability. Mean values of pH, available $P_2O_5$, OM, Ca, Mg and K for topsoil were 5.6, 31ppm, 3.2%, 2.23me/100gr, 1.05me/100gr, and 0.37me/100gr, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.134-139
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• 1985

This study was designed to understand the relationships among the soil physical and chemical properties and to obtain the useful regression to calculate the cation exchange capacity, field capacity, wilting point moisture content and organic matter content. Fourteen soil properties were collected from 315 representative soil series in Korea. Simple and multiple regression were analyzed with the data by grouping land use, drainage class and soil depth. The multiple regression equations which can be calculated the cation exchange capacity from clay and organic matter content were found out. Cation exchange capacity of clay was 22me/100g, and that of organic matter was 103.3me/100g. Moisture retentions, both of wilting point moisture content and field capacity, were closely related to clay and organic matter content. The coefficient of clay was increased with drainage class changed more poor but the coefficient of organic matter was highest at moderately well drained soil. Organic matter content can be calculated by soil texture and pH. Organic matter content was decreased by in creasing the pH. The highly significant regressions were found between base saturation and pH.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.183-191
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• 1991

A study was conducted to determine the influence of soil chemical properties on the distribution and forms of cadmium (Cd), lead (Pb), copper(Cu) and Zinc(Zn) in paddy soils near zinc mines. A sequential extraction procedure was used to fractionate the heavy metals in soils into the designated from of water soluble, exchangeable, organically bound, oxide/carbonate, and sulfide/residual. The predominant form of Cd, Pb, Cu and Zn in the soils was found to be sulfide/residual form. Oxide/carbonate Cd and Pb and organically bound Cu were high, while exchangeable Pb and Cu were very low. Water soluble Cd, Pb and Cu were not detected in the soils. The percentages of the heavy metals content in exchangeable fractions were inversely correlated with those in sulfide/residual fractions in the soils. Exchangeable Cd and Zn and the oxide/carbonate Pb were shifting to the sulfide/residual form with soil depth and the chemical forms of Cu were not changed. Organically bound Cu was positively correlated with soil organic matter content but Cd, Pb and Zn were not. The percentages of Cd, Pb and Zn content in exchangeable forms decreased with soil pH, while those in oxide/carbonate and sulfide/residual forms increased with soil pH. The amounts of oxide/carbonate and sulfide/residual forms of pb were higher than those of Cd and Zn at same soil pH.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.380-386
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• 2001

This study was conducted to investigate the influence of the root zone temperature on the changes in soil physicochemical environment and the growth of the apple trees. Root zone temperatures applied were 20. 25. 30. and $35^{\circ}C$. A pot experiment of 4-year-old fruit-bearing Fuji/M.26 apple trees was done from May 15. 1997 to August 15. 1997. Shoot length and shoot number of 4-year-old Fuji/M.26 was longest at $30^{\circ}C$ but decreased at $35^{\circ}C$. Oxygen concentrations in soil air were maintained from 17 to 18% at $20^{\circ}C$ but fluctuated from 10 to 14% at the end at $35^{\circ}C$. Carbon dioxide concentrations in soil air was highest at $35^{\circ}C$. Organic matter contents in soil decreased as root zone temperature and duration of treatment increased. Nitrate and ammonium contents in soil increased with rising root zone temperature in the beginning but nitrate contents decreased at $35^{\circ}C$ as time progressed. Nitrate content was higher in 10~15cm subsoil than in 25~30cm subsoil.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.126-130
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• 1983

This study was desinged to find out the effects of soil physical properties on root development of barley. Barley fields were selected in consideration of drainage class and texture. Soil hardness were measured at the field. Soil bulk density, air ratio and root distribution were obtained from the core samples. 1. The amount of roots were increased and the root were distributed deeper layers with better drainage class and finer soil texture. 2. Soil hardness was related to soil bulk density, and the regression coefficient was increased with clay content (Clay ; $r=0.837^{**}$, Clay loam ; $r=0.678^*$, and Sandy loam ; $r=0.654^*$). 3. There was a highly negative correlation ($r=-0,846^{**}$) between bulk density of subsoils and amount of roots and the root developments were markedly reduced in soil bulk density of $1.4g/cm^3$. 4. Bulk density of subsoils was decreased with worse soil drainage and finer texture. Especially, in case of clayey soil at imperfectly or moderately drained soils, the air phase was less than 20% and the barley growth was worse. 5. Root development were related to hardness in surface, bulk density and ok phase in 10-30cm layer, and air phase in 30-50cm layer.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.1-6
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• 1987

This study was designed to evaluate the characteristics, land use and genesis of well adapted paddy soils. They were mostly classified as the Haplaquepts in the U.S.D.A soil taxonomy and as the Grey soils in the Japanese soil classification system. The proportion of these soils in the total acreage of paddy lands was thirty three percents. The fifty four percents in average of these soils were distributed on the local valley and fans on gentle slopes developed from granite, granite gneiss and shale parent materials. The rests were on the fluvio-marine deposits and alluvial deposits. The soils were characterized with prominant development of gleized horizons and clayey or fine loamy textured category. The available soil depth and the ground water level were relatively deep. The base saturation percent were high with weak acidic pH. The potential productivity of these soils was high.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.189-193
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• 1985

A field experiment was conducted to find out the effects of tillage methods on the changes of soil physical properties and rice yields. Silty clay loam soil was treated with six kinds of different tillage methods, cultivator plow-rotary, rotary, tractor deep plow-rotary, subsoiling-rotary, chisel plow-rotary and no-tillage, and Jinju variety of rice was cultivated. The results were summarized as follows; 1. Working efficiency was highest at chisel plow and the efficiencies were decreased with the order of deep plow, subsoiling, rotary, and cultivator plow. 2. Deep plow and chisel plow were considered as the useful treatments of physical properties to 20 cm depth soil and subsoiling was effective to 40 cm depth soil. 3. Rice yields were decreased 4% by rotary and 11% by no-tillage compare to cultivator plow-rotary but the yields were increased 5% by deep plow, 4% by subsoiling and 3% by chisel plow. As the results of all the data, welting efficiency, soil physical properties and rice yields, tractor deep plow was recommendable tillage method for rice paddy soils.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.177-182
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• 1991

This study was carried out to clarify the effects of grassland afforestation on some chemical properties of the Japanese ceder(Cryptomeria japonica) forest soil in Cheju Island. The following results were obtained in this study ; 1. T-C, T-N, exch. cations and base saturation in the surface soil(0~10cm) decreased sharply from planting to crown closure. However, after crown closure, exch. Ca and Mg increased considerably. On the other hand, there were no definit changes below surface soil. 2. In vertical distribution of chemical properties, T-C, T-N, exchangeable acidity and exch. cations decreased with soil depth. Especially, exch. Ca and Mg of surface soil in closed stand show a higher value than that in open stand, but there were no variation below surface soil. 3. In closed stand, the amounts of exch. Ca, Mg and K were 1.8 times, 1.6 times and 1.5 times greater than those in open stand. There was no significant difference between open and closed stand in T-C and T-N. 4. The ratios of the amounts of nutrients in surface soil to those in mineral horizons(ha, 50cm) between the open and closed stand showed 30% and 50% for exch. Ca, 30% and 40% for exch. Mg, 38% and 38% for exch. K, respectively.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.12-17
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• 1985

soil survey and chemical analysis on mulberry nursery garden were carried out to study the causes of the non-sprouting phenomenon occured seriously in Buy and Ogchun in 1983 and Sangju in 1984. In addition, 115 nursery garden soils taken from 21 sapling produsers in Chungbuk province were analyzed in 1984. The results were as follows, 1. Symptom of dead saplings was the highest in boron deficiency by 59% and the lowest in rot symptom. The rest of saplings by 34.9% were not detected any symptom. 2. The nursery gardens showen non-sprouting phonomenon were located along the stream. As the result, soil depth was shallow, around 20cm deep and subsoil composed with coarse sand and gravels. 3. Nursery soils were mostly strong acid, low in Ca and Mg content, especially B, whereas available phosphorus and potassium were abundant at some gardens, and deficient at others. 4. Application of red earth or borax to nursery garden, especially to paddy, increased sprouting rate. 5. Paddy nursery garden occupied by 52.8% of 60.8ha of total garden area in Chungbuk province. Ninty point five percent of the nursery garden was lower in pH than 6.5, 87.0% lower in K than 0.5me/100g, 40.8% lower in Ca than 6.5me/100g, 94.8% lower in Mg the 2.00me/100g 99.1% lower in B than 0.3ppm.