• Korean Journal of Mineralogy and Petrology
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• v.34 no.4
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• pp.241-253
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• 2021

Manganese nodules have been found in the shallow water depth of the Arctic Ocean as well as in the abyssal plains of the Pacific and Indian Oceans, but detailed study for them were rarely investigated. Manganese nodules, collected from the East Siberian Sea through the Arctic Expedition using Araon ice braking vessel, have a high potential for Mn mineral resources because they have high Mn content with high Mn/Fe ratio. This study investigated the external form, size and weight, internal texture for the non-spherical manganese nodule, which has about 7 % of total nodule from the East Siberian Sea. This study also researched the relative Mn-oxide mineral composition using the peak area ratio of X-ray diffraction pattern and their chemical composition. All data obtained from non-spherical nodules were compared with the spherical ones. Ellipsoidal, platy and irregular types are common among 5 groups of non-spherical manganese nodule based on the external form, and major axis and weight have positive relationship. All non-spherical manganese nodules have core mainly composed of mud sediments. The average Mn oxide mineral contents in nodules are birnessite, buserite and todorokite in descending order. Although mineral composition does not show any correlation with the external form, kind of core or internal structure, todorokite and buserite contents tend to increase and birnessite content decrease from the surface to the core in the nodule. Non-spherical manganese nodules have higher Mn content and Mn/Fe ratio than those from the shallow water depth of the Arctic Sea and even in the deep-sea of the Pacific and Indian Ocean. Although non-spherical nodule is larger and heavier, and has lower Mn content and Mn/Fe ratio than spherical nodule, there are not any differences in mineral composition and internal structure between them. Almost all manganese nodules collected from the East Siberian Sea are attributed to diagenetic process, because they are higher than 5 in Mn/Fe ratio.

• Korean Journal of Poultry Science
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• v.49 no.1
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• pp.1-8
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• 2022

We investigated the effects of stunning methods and gas treatments during slaughter on the quality characteristics of chicken breast and small intestine. Broilers (Ross 308) were stunned and slaughtered using halal, CO₂, or N₂ gas stunning methods (for 10 birds). After slaughter, the pH, proximate composition, color, water-holding capacity, cooking loss, and shear force of chicken breast muscle and small intestine were determined. Compared with the halal treatment, CO₂ treatment resulted in higher pH and lower cooking loss (P<0.05), and the pH, color, and shear force of chicken breast muscle with N₂ treatment were similar to those of the halal treatment (P>0.05). Compared with the halal treatment, the gas treatments resulted in lower pH and lightness and higher redness, yellowness, thickness, and shear force of the small intestine (P<0.05). However, compared with the CO₂ treatment, the N₂ treatment resulted in lower pH, redness, and yellowness, and higher lightness, thickness, and shear force. Overall, compared with the halal method, our results suggest that the use of N₂ gas suppresses the discoloration and deterioration of the texture of chicken meat and small intestine caused by CO₂ gas treatment in the gas stunning method.

• Journal of Animal Science and Technology
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• v.45 no.6
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• pp.1007-1018
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• 2003

This study was conducted to investigate the effect of feeding of garlic stalk silage on performance and carcass characteristics of Hanwoo steers. Feeding trial was conducted with 27 heads of Hanwoo steers and these animals were divided into two groups of control(rice straw) and garlic stalk silage. Animals consuming rice straw were fed concentrates and rice straw for 22 months from the 5 months of age and animals consuming garlic stalk silage were fed concentrates, rice straw and garlic stalk silage for 22 months from the 5 months of age. Animals fed rice straw and garlic stalk silage were fed 1.34 and 1.47, 1.69 and 1.74, 1.65 and 1.66% concentrates to body weight for the growing period, fattening period and finishing period, respectively. Animals fed rice straw and garlic stalk silage as roughage sources were fed 1.37 and 1.38, 0.65 and 0.63, 0.43 and 0.43% roughages to body weight for the growing period, fattening period and finishing period, respectively. Also, animals fed garlic stalk silage were offered 0.22 and 0.33% garlic stalk silage to body weight for the fattening and finishing period, respectively. Animals fed rice straw and garlic stalk silage as a roughage sources did not differ in average daily gain during the whole feeding periods. Animals of control group consumed less concentrates and roughage than those fed garlic stalk silage during the whole feeding periods. However, feed efficiency was not significantly different between both treatments. Beef yield including backfat thickness, eye muscle area and carcass weight was slightly lower in the animals fed garlic stalk silage than in the animals fed rice straw even though there were no differences between both treatments. However, beef quality including beef color, fat color, texture, maturity and marbling score was slightly higher in the garlic stalk silage-fed animals than in the animals fed rice straw although there were not statistically different between both treatments. Animals consuming garlic stalk silage was significantly(p<0.05) lower in shear value than those fed rice straw. Amino acid composition including essential amino acid and non-essential amino acid was not different between animals fed rice straw and garlic stalk silage. Eye muscle area of animals fed garlic stalk silage contained slightly higher oleic acid, less linoleic acid and arachidonic acid and more linolenic acid than that of animals fed rice straw only as a roughage sources. So eye muscle area of animals fed garlic stalk silage contained more mono-unsaturated fatty acid than that of animals fed rice straw and $\omega$6/$\omega$3 ratio was narrower in the animals fed garlic stalk silage than in the animals fed rice straw. Economic income was higher by 20% in the animals fed garlic stalk silage than in the animals fed rice straw. Therefore, It may be concluded that feeding of garlic stalk silage as a roughage sources to steers during the fattening period seems to improve meat quality, fatty acid composition and economic income.

• Korean Journal of Soil Science and Fertilizer
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• v.2 no.1
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• pp.15-26
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• 1969

The study on physico-chemical characteristics of the acid sulfate soil present in Kimhae plain was carried out with 28 surface and subsoils from lower and higher produtive area and two representative profile samples from the areas reclaimed a few decades ago and around 10 years ago respectively. 1. There are no differences in soil texture between lower and higher productive soils being mostly silty clay loam and silty clay. 2. Very significant differences in pH, degree of base saturation and extractable aluminium content are observed; lower pH, lower degree of base saturation and higher aluminium in the lower productive soils and subsoils. The pH and degree of base saturation of these soils are extremely low whereas aluminium content is very high compared to ordinary paddy soil. 3. Cation exchange capacity of these soils are slightly higher than ordinary paddy soils. In higher productive soils, exchangeable calcium and magnesium are of same order, whereas in lower productive soils magnesium content is appreciably higher than calcium. 4. Though the soil is derived from marine and estuarine sediment, the soluble salt content is not high. There are only few lower productive surface soils and subsoils having Ec values of the saturation extracts higher than 4 mmhos but lower than 9 mmhos/cm. 5. Organic matter content of these soils is a bit higher compared to ordinary paddy soils, but, nitrogen content is comparatively low. C/N ratio of these soils is around 12. 6. Sulfur content is considerably higher but oxidizable sulfur is found to be very low. Total sulfur is generally high in subsoils and lower productive soils. 7. Active iron and available silica are slightly higher than ordinary paddy soils but easily reducible manganese is very low. Almost no differences are also observed between lower and higher productive soils. 8. Available phosphorus content is extremely low in particular, regardless of higher or lower productive soils. 9. The two representative profiles from the area of earlier reclamation and recent one show that samples from earlier reclaimed area contain less amount of free acids, sulfur compounds, toxic aluminium and soluble salts etc. than the other. This indicate greater leaching and possible addition of lime for a longer period of time. 10. From the results obtained, it can be concluded the higher productivity of group I soils is due to the greater leaching and neutralisation of acidity by liming materials, It can also be concluded that the productivity of both types can be increased by addition of liming materials and improvement of drainage facilities.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.841-849
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• 2013

The aim of this study was to investigate the quality characteristics of Kimchi, prepared with seasoning fluid, vinegar, and mustard extract to inhibit the proliferation of microorganisms and extend the edible period during fermentation at $25^{\circ}C$. We also added perilla leaf, endive, and mustard leaf to Kimchi to improve the flavor. The pH of control Kimchi fluid over 1 day after Kimchi processing, was $5.40{\pm}0.01$ and that of the experimental groups in which vinegar and mustard extract were added was $4.51{\pm}0.01{\sim}4.52{\pm}0.01$, which was lower than that of the control. As the fermentation progresses, the pH of the control decreased rapidly and that of the experimental groups decreased slowly. The initial titratible acidity of the control was low and 3 days later reached $0.95{\pm}0.04$. However, that of the experimental groups was $0.42{\pm}0.01{\sim}0.43{\pm}0.02$ and 5 days later reached a level similar to that of the control. The salinities of the Kimchi juice of both the control and the experimental groups were $2.67{\pm}0.06{\sim}2.80{\pm}0.10$% after 1 day and decreased during fermentation. The amount of lactic acid bacteria of the control was $8.17{\pm}4.01{\times}10^8cfu/g$, 1 day after the Kimchi processing and that of the experimental groups was $2.70{\pm}2.08{\times}10^7{\sim}3.63{\pm}2.80{\times}10^7cfu/g$. After 3 days, these were $3.13{\pm}1.94{\times}10^{11}cfu/g$ and $2.47{\pm}2.23{\times}10^9{\sim}8.03{\pm}3.71{\times}10^9cfu/g$, respectively. According to the result of sensory evaluation, throughout the entire period of the experiment, all sensory items such as color, odor, taste, texture, and total acceptability of the experimental groups were better than those of the control group (p<0.05). Especially, Kimchi in which perilla leaf was added was the best. With the addition of vinegar and mustard extract to the Kimchi, microorganism proliferation was inhibited and the edible period was extended. The minerals, vitamins and antioxidants of leaf vegetables could therefore be obtained.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.1-11
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• 2008

As conventional oil and gas reservoirs become depleted, interests for oil sands has rapidly increased in the last decade. Oil sands are mixture of bitumen, water, and host sediments of sand and clay. Most oil sand is unconsolidated sand that is held together by bitumen. Bitumen has hydrocarbon in situ viscosity of >10,000 centipoises (cP) at reservoir condition and has API gravity between $8-14^{\circ}$. The largest oil sand deposits are in Alberta and Saskatchewan, Canada. The reverves are approximated at 1.7 trillion barrels of initial oil-in-place and 173 billion barrels of remaining established reserves. Alberta has a number of oil sands deposits which are grouped into three oil sand development areas - the Athabasca, Cold Lake, and Peace River, with the largest current bitumen production from Athabasca. Principal oil sands deposits consist of the McMurray Fm and Wabiskaw Mbr in Athabasca area, the Gething and Bluesky formations in Peace River area, and relatively thin multi-reservoir deposits of McMurray, Clearwater, and Grand Rapid formations in Cold Lake area. The reservoir sediments were deposited in the foreland basin (Western Canada Sedimentary Basin) formed by collision between the Pacific and North America plates and the subsequent thrusting movements in the Mesozoic. The deposits are underlain by basement rocks of Paleozoic carbonates with highly variable topography. The oil sands deposits were formed during the Early Cretaceous transgression which occurred along the Cretaceous Interior Seaway in North America. The oil-sands-hosting McMurray and Wabiskaw deposits in the Athabasca area consist of the lower fluvial and the upper estuarine-offshore sediments, reflecting the broad and overall transgression. The deposits are characterized by facies heterogeneity of channelized reservoir sands and non-reservoir muds. Main reservoir bodies of the McMurray Formation are fluvial and estuarine channel-point bar complexes which are interbedded with fine-grained deposits formed in floodplain, tidal flat, and estuarine bay. The Wabiskaw deposits (basal member of the Clearwater Formation) commonly comprise sheet-shaped offshore muds and sands, but occasionally show deep-incision into the McMurray deposits, forming channelized reservoir sand bodies of oil sands. In Canada, bitumen of oil sands deposits is produced by surface mining or in-situ thermal recovery processes. Bitumen sands recovered by surface mining are changed into synthetic crude oil through extraction and upgrading processes. On the other hand, bitumen produced by in-situ thermal recovery is transported to refinery only through bitumen blending process. The in-situ thermal recovery technology is represented by Steam-Assisted Gravity Drainage and Cyclic Steam Stimulation. These technologies are based on steam injection into bitumen sand reservoirs for increase in reservoir in-situ temperature and in bitumen mobility. In oil sands reservoirs, efficiency for steam propagation is controlled mainly by reservoir geology. Accordingly, understanding of geological factors and characteristics of oil sands reservoir deposits is prerequisite for well-designed development planning and effective bitumen production. As significant geological factors and characteristics in oil sands reservoir deposits, this study suggests (1) pay of bitumen sands and connectivity, (2) bitumen content and saturation, (3) geologic structure, (4) distribution of mud baffles and plugs, (5) thickness and lateral continuity of mud interbeds, (6) distribution of water-saturated sands, (7) distribution of gas-saturated sands, (8) direction of lateral accretion of point bar, (9) distribution of diagenetic layers and nodules, and (10) texture and fabric change within reservoir sand body.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.1
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• pp.41-56
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• 2021

The characteristics of the six rock cleavages(R1~H2) in Jurassic Hapcheon granite were analyzed using the distribution of ① microcrack lengths(N=230), ② microcrack spacings(N=150) and ③ Brazilian tensile strengths(N=30). The 18 cumulative graphs for these three factors measured in the directions parallel to the six rock cleavages were mutually contrasted. The main results of the analysis are summarized as follows. First, the frequency ratio(%) of Brazilian tensile strength values(kg/㎠) divided into nine class intervals increases in the order of 60~70(3.3) < 140~150(6.7) < 100~110·110~120(10.0) < 90~100(13.3) < 80~90(16.7) < 120~130·130~140(20.0). The distribution curve of strength according to the frequency of each class interval shows a bimodal distribution. Second, the graphs for the length, spacing and tensile strength were arranged in the order of H2 < H1 < G2 < G1 < R2 < R1. Exponent difference(λS-λL, Δλ) between the two graphs for the spacing and length increases in the order of H2(-1.59) < H1(-0.02) < G2(0.25) < G1(0.63) < R2(1.59) < R1(1.96)(2 < 1). From the related chart, the six graphs for the tensile strength move gradually to the left direction with the increase of the above exponent difference. The negative slope(a) of the graphs for the tensile strength, suggesting a degree of uniformity of the texture, increases in the order of H((H1+H2)/2, 0.116) < G((G1+G2)/2, 0.125) < R((R1+R2)/2, 0.191). Third, the order of arrangement between the two graphs for the two directions that make up each rock cleavage(R1·R2(R), G1·G2(G), H1·H2(H)) were compared. The order of arrangement of the two graphs for the length and spacing is reverse order with each other. The two graphs for the spacing and tensile strength is mutually consistent in the order of arrangement. The exponent differences(ΔλL and ΔλS) for the length and spacing increase in the order of rift(R, -0.08) < grain(G, 0.14) < hardway(H, 0.75) and hardway(H, 0.16) < grain(G, 0.23) < rift(R, 0.45), respectively. Fourth, the general chart for the six graphs showing the distribution characteristics of the microcrack lengths, microcrack spacings and Brazilian tensile strengths were made. According to the range of length, the six graphs show orders of G2 < H2 < H1 < R2 < G1 < R1(< 7 mm) and G2 < H1 < H2 < R2 < G1 < R1(≦2.38 mm). The six graphs for the spacing intersect each other by forming a bottleneck near the point corresponding to the cumulative frequency of 12 and the spacing of 0.53 mm. Fifth, the six values of each parameter representing the six rock cleavages were arranged in the order of increasing and decreasing. Among the 8 parameters related to the length, the total length(Lt) and the graph(≦2.38 mm) are mutually congruent in order of arrangement. Among the 7 parameters related to the spacing, the frequency of spacing(N), the mean spacing(Sm) and the graph (≦5 mm) are mutually consistent in order of arrangement. In terms of order of arrangement, the values of the above three parameters for the spacing are consistent with the maximum tensile strengths belonging to group E. As shown in Table 8, the order of arrangement of these parameter values is useful for prior recognition of the six rock cleavages and the three quarrying planes.

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.31-40
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• 2003

A research has been done for growing characteristics of Korean ginseng in Geumsan of Chungnam Province. It had been made to determine the transitional element concentrations of the rocks, divided by biotitic granite(GR) and phyllite(PH). The physical and chemical properties of their weathering soils and ginseng nursery soils were analyzed. The texture in the GR weathering and ginseng nursery soils were sandy clay, and the texture of the PH weathering and ginseng nursery soils were heavy or silty clay. The bulk densities of the GR and PH weathering soils were $1.21{\sim}1.32g/cm^3$ and $1.26{\sim}1.38g/cm^3$, respectively. Also, the bulk densities of the GR and PH ginseng nursery soils were $1.02{\sim}1.10g/cm^3$, respectively. The pH (4.80) of the GR weathering soil were lower than the pH of the PH(5.34) weathering soil. The pH in the 2 year and 4 year-ginseng nursery soil of the GR were 4.39 and 4.40. In addition, those of the PH were 5.24 and 5.34, respectively. The difference in pH of the two nursery soils could be from the pH difference between the two parent materials. The organic matter contents of the GR weathering soils(0.24%) were higher than those of the PH(1.02%) weathering soils. The organic matter of the 2 and 4 year-ginseng GR nursery soils were 0.87% and 1.52%, and of the PH nursery soils were 2.06% and 2.96%, respectively. The total nitrogen contents of the GR weathering soils were 259.43ppm and of the PH weathering soils were 657.22ppm. Those of 2 and 4 year-ginseng GR nursery soils were 588.04ppm and 657.22ppm and those of the PH nursery soils were 1037.72ppm and 1227.96ppm, respectively. The nitrate and ammonium contents of the GR weathering soils were the extremely small, and those of the PH weathering soils were 6.7ppm and 9.94ppm. Those of 2 year-ginseng GR nursery soils(223.09ppm and 26.96ppm) were higher than those of PH(19.46ppm and 8.23ppm) nursery soils. And those of 2 year-ginseng PH nursery soils(14.22ppm and 16.84ppm) were lower than those of PH(306.93ppm, 34.21ppm) nursery soils. The difference was due to fertilizer types and more deposits of nitrate after oxidation of ammonium. The phosphate contents of the GR and PH weathering soils were 14.41ppm and 38.60ppm. Those of GR 2 and 4 year-ginseng nursery soils were 46.89ppm and 102.44ppm and those of the PH nursery soils were 147.04ppm and 38.60ppm. The cation exchange capacities of the GR weathering soils were 12.34me/100g and those of the PH weathering soils were 15.40me/100g. Those of 2 and 4 year-ginseng GR nursery soils were 15.80me/100g and 7.70me/100g and those of PH nursery soils were 12.14me/100g and 12.83me/100g. All of exchangeable cation($K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$) contents in the nursery soils were higher than those in the weathering soils. The $SO_4{^2-}$ contents of the weathering soils in both of the GR(5.98ppm) and PH(9.94ppm) were higher than those of the GR and PH ginseng nursery soils. The $Cl^-$) contents of the GR and PH weathering soils were a very small and those of the nursery soils(2-yr GR: 39.06ppm, 4-yr GR: 273.43ppm, 2-yr PH: 66.41ppm, 4-yr PH: 406.24ppm) were high because of fertilizer inputs.

• Journal of the Korean Wood Science and Technology
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• v.6 no.2
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• pp.3-19
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• 1978

Five species, Abies koreana Wilson (A. koreana), Castanopsis cuspidata var. Sieboldii Nakai (C. Cuspidata). Machilus thunbergii Sieb. et Zucc. (M. thunbergii), Styrax japonica (S. japonica), and Quercus acuta Thunberg(Q. acuta) growing in the southern part of Korea were selected for the investigation of wood properties. In order to evaluate the wood properties of these five species, anatomical, physical, mechanical, chemical and pulping characteristics were investigated. And this study also covered wood technological problems related to the drying, gluing, debarking, flooring, and wood workability so that these species might serve to the best advantage. The results obtained were summarized as follows: 1. The trunk of A. koreana with many knots was straight. However, the trunks of S. japonica and C. cuspidata were crooked. 2. A. koreana showed the longest and the widest ill the fiber morphology; 2.97mm in length, 39.3${\mu}$ in width. In general, fiber width of all the species investigated were greater than those of other Korean hardwoods. 3. The specific gravity of Q. acuta was 0.74${\pm}$0.03, and that of A.koreana was 0.34${\pm}$0.02. The range of specific gravity of the other species was 0.47-0.52. 4. The adsorption of water was propotioned inversely with the specific gravity, but the adsorption of humidity was proportioned with the specific gravity. In spite of their medium density, S. japonica showed the greatest adsorption, and M. thunbergii the least. The water adsorption of cross section was twice greater than that of lateral direction, and there was a slight difference in between the radial and the tangential direction. 5. Shrinkage for tested five species was ranged from 5.36 to 10.24% in tangential direction, and 2.83~6.13% in radial direction. Q. acuta recorded the greatest shrinkage rate, and A. koreana the least. The greater was the specific gravity, the larger was the shrinkage rate. 6. The mechanical properties of Q. acuta were similar to those of Quercus mongolica which grow in Kangwon-Do. Strength properties of C. cuspidata, M. thunbergii, A. koreana were equivalent to those of other Korean commercial woods with similar specific gravity, except S. japonica which showed slightly higher strength than that of other species with similar density. 7. Higher glue joint strength for urea and phenol adhesieves was recorded in the species of M. thunbergii and C. cuspidata, however, high-density species(Q. acuta) and even low-density species(A. koreana) did not show good joint strength. 8. The attractive figure of M. thunbergii in texture seemed to he appreciated for decoration. And the grain and texture of other species were proper for furniture and building materials. 9. All of the species except Q. acuta were considered good for wood workability. 10. The denser the specific gravity was, the longer the drying time took. However, severe drying defects were formed in M. thunbergii whose density was medium. 11. All the species were considered suitable for the flooring wood expect A. koreana whose density was light. 12. Pentosan component in all the species was great, and the amount of extractives in Q. acuta was worth noticing. 13. Yield in kraft pulp was above the level of economic pulp yield, i.e. 45% in all species. 14. Debarking was easy in the species of A. koreana and M. thunbergii, and debarking after being boiled in water was the most efficient in all species.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.171-188
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• 1977

The response and effect on main upland crops to potassium were discussed and summarized as follows. 1. Adequate average amounts of potash per 10a were 32kg for forage crop; 22.5kg for vegetable crops; 17.3kg for fruit trees; 13.3kg for potatoes; and 6.5kg for cereal crops. Demand of potassium fertilizer in the future will be increased by expanding the acreage of forage crops, vegetable crops and fruit trees. 2. On the average, optimum potash rates on barley, wheat, soybean, corn, white potato and sweet potato were 6.5, 6.9, 4.5, 8.1, 8.9, and 17.7kg per 10a respectively. Yield increaments per 1kg of potash per 10a were 4-5kgs on the average for cereal crops, 68kg for white potato, and 24kg for sweet potato. 3. According to the soil testing data, the exchangeable potassium in the coastal area was higher than that in the inland area and medium in the mountainous area. The exchangeable potassium per province in decreasing order is Jeju>Jeonnam>Kangweon>Kyongnam. Barley : 4. The response of barley to an adequate rate of potassium seemed to be affected more by differences in climatic conditions than to the nature of the soil. 5. The response and the adequate rate of potassium in the southern area, where the temperature is higher, were low because of more release of potassium from the soil. However, the adequate rate of phosphorus was increased due to the fixation of applied phosphorus into the soil in high temperature regions. The more nitrogen application would be required in the southern area due to its high precipitation. 6. The average response of barley to potassium was lower in the southern provinces than northern provinces. Kyongsangpukdo, a southern province, showed a relatively higher response because of the low exchangeable potassium content in the soil and the low-temperature environment in most of cultivation area. 7. Large annual variations in the response to and adequate rates of potassium on barley were noticed. In a cold year, the response of barley to potassium was 2 to 3 times higher than in a normal year. And in the year affected by moisture and drought damage, the responses to potassium was low but adequate rates was higher than cold year. 8. The content of exchangeable potassium in the soil parent materials, in increasing order was Crystalline Schist, Granite, Sedimentary and Basalt. The response of barley to potash occurred in the opposite order with the smallest response being in Crystalline Schist soil. There was a negative correlation between the response and exchangeable potassium contents but there was nearly no difference in the adequate rates of potassium. 9. Exchangeable potassium according to the mode of soil deposition was Alluvium>Residium>Old alluvium>Valley alluvium. The highest response to potash was obtained in Valley alluvium while the other s showed only small differences in responses. 10. Response and adequate rates of potassium seemed to be affected greatly by differences in soil texture. The response to potassium was higher in Sandy loam and Loam soils but the optimum rate of potassium was higher in Clay and Clay loam. Especially when excess amount of potassium was applied in Sandy loam and Loam soils the yield was decreased. 11. The application of potassium retarded the heading date by 1.7 days and increased the length of culm. the number of spikelet per plant, the 1,000 grain weight and the ratio of grain weight to straw. Soybean : 12. Average response of soybean to potassium was the lowest among other cereal crops but 28kg of grain yield was incrased by applying potash at 8kg/10a in newly reclaimed soils. 13. The response in the parent materials soil was in the order of Basalt (Jeju)>Sedimentay>Granite>Lime stone but this response has very wide variations year to year. Corn : 14. The response of corn to potassium decreased in soils where the exchangeable potassium content was high. However, the optimum rate of applied potassium was increased as the soil potassium content was increased because corn production is proportional to the content of soil potassium. 15. An interaction between the response to potassium and the level of phosphorus was noted. A higher response to potassium and higher rates of applied potassium was observed in soils contained optimum level of phosphorus. Potatoes : 16. White potato had a higher requirement for nitrogen than for potassium, which may imply that potato seems to have a higher capability of soil potassium uptake. 17. The yield of white potato was higher in Sandy loam than in Clay loam soil. Potato yields were also higher in soils where the exchangeable potassium content was high even in the same soil texture. However, the response to applied potassium was higher in Clay loam soils than in Sandy loam soils and in paddy soil than in upland soil. 18. The requirement for nitrogen and phosphorus by sweet potato was relatively low. The sweet potato yield is relatively high even under unfavorable soil conditions. A characteristics of sweet potatoes is to require higher level of potassium and to show significant responses to potassium. 19. The response of sweet potato to potassium varied according to soil texture. Higher yields were obtained in Sandy soil, which has a low exchangeable potassium content, by applying sufficient potassium. 20. When the optimum rate of potassium was applied, the yields of sweet potato in newly reclaimed soil were comparable to that in older upland soils.