• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.93-101
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• 2010

For the study of possibility of practical use as an organic farm materials of the mixtures with lignite and amino acid solution, this experiment was carried out to investigate the effects of the mixtures on the growth and the yield of rice plant, chinese cabbage, and red pepper, and the effects of the mixtures on chemical properties of soil. Also, when the mixtures of the lignite plus amino acid solution and the chemical fertilizer were applied to these three crop cultivation area, authors want to know how can the loss in quantity of chemical fertilizer affects the growth and the yield of these crops. As the results, growth of rice plant applied with the mixtures of lignite and amino acid solution was better than that applied with the recommended rate of chemical fertilizer. Especially, the growth of rice plant appeared to be good at the treatment of 150 kg/ha of the mixed lignite with amino acid solution and at that of its mixtures and standard fertilization. Growth of chinese cabbage and red pepper was good at the application of 600 kg/ha of the mixed lignite with amino acid solution and at that of its mixtures and standard fertilization. Yield of rice and chinese cabbage was good at the treatment of 150 kg/ha of the mixed lignite with amino acid solution and at that of its mixtures and standard fertilization, and yield of red pepper was good at the application of 600 kg/ha of the mixed lignite with amino acid solution and at that of its mixtures and standard fertilization. The organic matter content increased and while the exchangeable cation decreased when the lignite mixed with amino acid solution and the loss in quantity of chemical fertilizer applied at paddy field. Incase of these treatments, pH and available phosphorus increase at upland field, but did not change at paddy field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.33-54
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• 2002

Rice quality is much dependent on the pre-and post harvest management. There are many parameters which influence rice or cooked rice qualitys such as cultivars, climate, soil, harvest time, drying, milling, storage, safety, nutritive value, taste, marketing, eating, cooking conditions, and each nations' food culture. Thus, vice evaluation might not be carried out by only some parameters. Physicochemical evaluation of rice deals with amy-lose content, gelatinizing property, and its relation with taste. The amylose content of good vice in Korea is defined at 17 to 20%. Other parameters considered are as follows; ratio of protein body-1 per total protein amount in relation to taste, and oleic/linoleic acid ratio in relation to storage safety. The rice higher Mg/K ratio is considered as high quality. The optimum value is over 1.5 to 1.6. It was reported that the contents of oligosaccharide, glutamic acid or its derivatives and its proportionalities have high corelation with the taste of rice. Major aromatic compounds in rice have been known as hexanal, acetone, pentanal, butanal, octanal, and heptanal. Recently, it was found that muco-polysaccharides are solubilized during cooking. Cooked rice surface is coated by the muco-polysaccharide. The muco-polysaccharide aye contributing to the consistency and collecting free amino acids and vitamins. Thus, these parameters might be regarded as important items for quality and taste evaluation of rice. Ingredients of rice related with the taste are not confined to the total rice grain. In the internal kernel, starch is main component but nitrogen and mineral compounds are localized at the external kernel. The ingredients related with taste are contained in 91 to 86% part of the outside kernel. For safety that is considered an important evaluation item of rice quality, each residual tolerance limit for agricultural chemicals must be adopted in our country. During drying, rice quality can decline by the reasons of high drying temperature, overdrying, and rapid drying. These result in cracked grain or decolored kernel. Intrinsic enzymes react partially during the rice storage. Because of these enzymes, starch, lipid, or protein can be slowly degraded, resulting in the decline of appearance quality, occurrence of aging aroma, and increased hardness of cooked rice. Milling conditions concerned with quality are paddy quality, milling method, and milling machines. To produce high quality rice, head rice must contain over three fourths of the normal rice kernels, and broken, damaged, colored, and immature kernels must be eliminated. In addition to milling equipment, color sorter and length grader must be installed for the production of such rice. Head rice was examined using the 45 brand rices circulating in Korea, Japan, America, Australia, and China. It was found that the head rice rate of brand rice in our country was approximately 57.4% and 80-86% in foreign countries. In order to develop a rice quality evaluation system, evaluation of technics must be further developed : more detailed measure of qualities, search for taste-related components, creation and grade classification of quality evaluation factors at each management stage of treatment after harvest, evaluation of rice as food material as well as for rice cooking, and method development for simple evaluation and establishment of equation for palatability. On policy concerns, the following must be conducted : development of price discrimination in conformity to rice cultivar and grade under the basis of quality evaluation method, fixation of head rice branding, and introduction of low temperature circulation.

• Korean Journal of Environmental Agriculture
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• v.23 no.3
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• pp.170-177
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• 2004

Agroenvironmental characteristics in paddy fields irrigated with the water of Nagdong river were analyzed along the river watershed for two years from 1999. The sites monitored from upper reaches of the river were Andong, Sangju, Gumi, Goryeong, Changnyeong, Milyang and Pusan. In paddy soils, the contents of heavy metals such as Cd, Cr, Cu, Pb, Ni, Zn and As were around natural values showing the highest values in Pusan followed by Goryeong. In brown rice, the contents of heavy metals were lower than natural values. Soil chemical properties appeared higher values in the lower reaches including Goryeong than the upper ones. The highest parameters in Goryeong were pH ($5.9{\sim}6.1$), EC ($0.8{\sim}0.9\;dS/m$), $Av.P_2O_5$ ($155{\sim}201\;mg/kg$), exchangeable Ca ($6.7{\sim}7.4\;cmol^+/kg$), Mg ($1.92{\sim}2.50\;cmol^+/kg$), K ($0.18{\sim}0.21\;cmol^+/kg$) and those in Pusan were organic matter ($23.0{\sim}29.1\;g/kg$) and T-N ($1.6{\sim}1.8\;mg/kg$). In conclusion, the recommended rates of N fertilizer for rice cropping were 21.4%, 11.8% and 8.8% high for Andong, Sangju and Gumi, respectively and 14.9%, 4.6%, 4.5% and 11.5% low for Goryeong, Changnyeong, Milyang and Pusan, respectively reflecting the chemical properties of soils and the quality of irrigation water on the basis of 110 kgN/ha. In the case of phosphorous, the rates were 18.9% and 33.3% low for Changnyeong and others, respectively on the basis of $45\;kgP_2O_5/ha$. The populations of bacteria, fungi, actinomycetes, Bacillus, fluorescent Pseudomonas and Biomass C were high at the lower reaches including Goryeong, which showed relatively much nutrient contents of organic matter, total N and phosphorous etc.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.43-60
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• 1968

In order to find the effects of nitrogen type (ammonium sulfate and urea fertilizer) and fertilized depth, (0~10cm, 0cm, 5~10cm, 10~15cm, 15~20cm, and 20cm below) on leaching and absorption of nitrogen in paddy soil, and growth and yields of rice, the pot culture experiment was carried out, using the variety Jaekun, one of the Korean leading variety. Experimental results were Summarized as follows: 1. No variations of the pH of percolating water were induced by the differences of nitrogen types and their fertilized depth (Table. 2). 2. The leaching of nitrogen was less in ammonium sulfate and top soil fertilizing plots than in urea and subsoil fertilizing plot, and the growth of rice in early stage was more promoted in ammonium sulfate and topsoil fertilizing plots (Table. 1, 7 and 8). 3. Leachng of nitrogen through the percolating water almost came to an end at the most numerous tiller stage (Table 1). 4. The absorption of nitrogen of each part of the rice plant in the harvesting stage correlated closely with the yields of each part (Table 5, 6, 9 and 10) and the leaching of nitrogen in the early stage was inversely proportion to the absorption of nitrogen of rice plant in the harvesting time (Table 1, 5, 6, 9 and 10). 5. The number of spikes was more numerous in ammonium sulfate plots than in urea plots on an average, so that the yields were higher in the ammonium sulfate plots than in urea plots although no differences in the grain number per spike were found in above two plots. The number of spikes was more numerous in topsoil fertilizing plots than in subsoil fertilizing plots, but the grain number per spike was less in former than in latter, so that no difference in yields was found. The absorption of nitrogen correlated closely with the yields in complete paddy grains (Table 5, 9, and 10). 6. At the ammonium sulfate fertilizing plots, the number of spikes was more numerous in topsoil fertilizing plots than in subsoil fertilizing plots, (among the each of the topsoil plots, 0~10cm and 5~10cm fertilizing plots kept more spikes than the 0cm fertilizing plots), but the grain number per spike was less in former than in latter (among the each of topsoil plots, no differences were found), so that no significant difference in yields was showed between the topsoil and subsoil fertilizing plots, but the results showed the tendency that the yields were highest in 0~10cm plots and the lowest in 20cm below plots. At the urea fertilizing plots, the number of spikes decreased in proportion to the increasing of fertilized depth, but no variations were found in the grain number per spike, so that the yields decreased in proportion to the increasing of fertilized depth. The absorption of nitrogen correlated closely with the yields in complete paddy grains (Table 5, 6, 9, and 10). 7. When fertilized in topsoil, the number of spikes was more numerous in ammonium sulfate plot than in urea plot, but the grain number per spike variated reversely, so that no differences were found in the yields between the ammonium sulfate and the urea plots, when fertilized in subsoil, both the number of spikes and the grain number per spike were larger in ammonium sulfate than in urea plot, so that the yields were also higher in ammonium sulfate plots (Table 5, 6, 9 and 10). 8. The weight of straw and its nitrogen absorption were higher in ammonium sulfate plot than in urea plot and decreased in proportion to the increasing of fertilized depth. Among the each of topsoil fertilizing plots, the 0~10cm and the 5~10cm fertilizing plots excelled the 0cm plot (Table 5, 6, 9 and 10). 9. No significant variations in the fertilizer treatments were found in the characters of heading date, maturing date, length of culm, length of spike, weight of empty grain, 1,000 grain weight, and one liter weight.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.164-168
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• 1999

For investigating transfer factors of $^{137}Cs$ in the arable land of Korea, mature crop plants and topsoils were collected from paddy and upland fields located at 33 areas of the country and $^{137}Cs$ concentrations were measured by ${\gamma}-spectrometry$. The $^{137}Cs$ concentrations in soil were in the range of $0.7{\sim}17.7$ Bq/kg-dry in the paddy fields and $1.2{\sim}27.8$ Bq/kg-dry in the upland fields. The $^{137}Cs$concentrations in hulled seed, detected for 12 areas only, were in the range of $0.019{\sim}0.111$ Bq/kg-dry and those in Chinese cabbage, detected also for 12 areas only, were in the range of $0.012{\sim}0.066$ Bq/kg-fresh. Soil-to-plant transfer factors of $^{137}Cs$ were in the range of $1.2{\times}10^{-3}{\sim}1.1{\times}10^{-2}$ for hulled seed and $6.8{\times}10^{-4}{\sim}1.7{\times}10^{-2}$ for Chinese cabbage. Inboth plant stuffs, the factor tended to decrease with increasing soil organic matter or cation exchange capacity and, in hulled seed, it tended to increase with increasing soil clay content. No statistical significance was, however, found in all those relationships. Present results can be utilized for estimating radiation risk resulting from the food consumption by Korean people and deciding agronomical counter-measures at the time of an nuclear accident.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.2
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• pp.89-96
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• 1975

The experiment was carried out to investigate the chemical properties of cement kiln dusts, abundantly produced from cement industry as a byproduct, and their effectiveness on rice yield. The field experiment was conducted on the acid paddy soil developed on basalt at Dongsong-Myon, Chulwon-Kun, Gangwon-Do. Two kinds of cement kiln dusts were used ; By Pass (BP) collected from the suspension preheater and Electric Precipitate (EP) from the cottrell electric precipitator. The levels of cement kiln dust applied were 100kg/10a, 200kg/10a and 300kg/10a, and the recommended variety "Nong Back" was adopted for this experiment. The results obtained are summarized as follows ; 1. The component of cement kiln dusts seems to be quite suitable for liming material. BP has 55% alkalinity, 41.7% of soluble calcium, 9.8% of soluble magnesium and 4.5% of water soluble silicate, while EP has 53.5% alkalinity, 41.7% soluble calcium, 8.3% soluble magnesium and 1% water soluble silicate. 2. The relative effectiveness of cement kiln dust in the soil will be superior due to very fine particle size. EP pass through completely 270 mesh screen, and 95% of BP pass through 150 mesh screen, 68% passing 270 mesh. 3. BP application at the rate of 100kg/10a increased 21% of rice yield as compared with control and EP 15%. It was observed that the affected yield components were increased panicle number per hill, grain number per panicle and 1,000 grains weight. 4. The application of optimum amount (100kg/10a) of cement kiln dusts accelerated the uptake of nutrients by rice plant and increased rice yield. However, the excess amounts (200kg/10a, 300kg/10a) of cement kiln dusts retarded the uptake of nutrients from soil.

• Korean Journal of Environmental Agriculture
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• v.5 no.1
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• pp.11-23
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• 1986

Soils and rice plants in wastewater irrigated area of the Mangyeong River receiving waster from the Jeonju Industrial Complex and municipal sewage were sampled at two depths to assess the nature and content of Cd, Cu, Pb and Zn, particularly with respect to distance from wastewater source. For metal levels of soils in these area, no difference in the heavy metal contents between the surface and the subsurface soils was found. Total contents of Cu, Pb and Zn in soils were negatively correlated with distance from the source. A positive correlation was found between contents of total and 0.1N-HCl extractable or $1N-CH_3COONH_4$ extractable heavy metals in surface soils of these area. Total contents of heavy metals in soils were positively correlated with clay, soil organic matter and cation exchange capacity. Heavy metal contents of brown rice sampled at the Jeon-ju Industrial Complex area ranged from 0.15 to 0.91 ppm for Cd, from 1.13 to 5.68 ppm for Cu, from 0.22 to 7.16 ppm for Pb and from 11.74 to 38.66 ppm for Zn. Negative correlation was found between the contents of Cd, Cu, Pb, and Zn in the brown rice and the distance from the source. The contents of Cd, Cu and Zn in rice straw were positively correlated with those in the brown rice.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.4
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• pp.1775-1782
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• 1969

The results of the study on the consumptine use of irrigated water in paddy fields during the growing season of rice plants are summarized as follows. 1. Transpiration and evaporation from water surface. 1) Amount of transpiration of rice plant increases gradually after transplantation and suddenly increases in the head swelling period and reaches the peak between the end of the head swelling poriod and early period of heading and flowering. (the sixth period for early maturing variety, the seventh period for medium or late maturing varieties), then it decreases gradually after that, for early, medium and late maturing varieties. 2) In the transpiration of rice plants there is hardly any difference among varieties up to the fifth period, but the early maturing variety is the most vigorous in the sixth period, and the late maturing variety is more vigorous than others continuously after the seventh period. 3) The amount of transpiration of the sixth period for early maturing variety of the seventh period for medium and late maturing variety in which transpiration is the most vigorous, is 15% or 16% of the total amount of transpiration through all periods. 4) Transpiration of rice plants must be determined by using transpiration intensity as the standard coefficient of computation of amount of transpiration, because it originates in the physiological action.(Table 7) 5) Transpiration ratio of rice plants is approximately 450 to 480 6) Equations which are able to compute amount of transpiration of each variety up th the heading-flowering peried, in which the amount of transpiration of rice plants is the maximum in this study are as follows: Early maturing variety ; Y=0.658+1.088X Medium maturing variety ; Y=0.780+1.050X Late maturing variety ; Y=0.646+1.091X Y=amount of transpiration ; X=number of period. 7) As we know from figure 1 and 2, correlation between the amount evaporation from water surface in paddy fields and amount of transpiration shows high negative. 8) It is possible to calculate the amount of evaporation from the water surface in the paddy field for varieties used in this study on the base of ratio of it to amount of evaporation by atmometer(Table 11) and Table 10. Also the amount of evaporation from the water surface in the paddy field is to be computed by the following equations until the period in which it is the minimum quantity the sixth period for early maturing variety and the seventh period for medium or late maturing varieties. Early maturing variety ; Y=4.67-0.58X Medium maturing variety ; Y=4.70-0.59X Late maturing variety ; Y=4.71-0.59X Y=amount of evaporation from water surface in the paddy field X=number of period. 9) Changes in the amount of evapo-transpiration of each growing period have the same tendency as transpiration, and the maximum quantity of early maturing variety is in the sixth period and medium or late maturing varieties are in the seventh period. 10) The amount of evapo-transpiration can be calculated on the base of the evapo-transpiration intensity (Table 14) and Tablet 12, for varieties used in this study. Also, it is possible to compute it according to the following equations with in the period of maximum quantity. Early maturing variety ; Y=5.36+0.503X Medium maturing variety ; Y=5.41+0.456X Late maturing variety ; Y=5.80+0.494X Y=amount of evapo-transpiration. X=number of period. 11) Ratios of the total amount of evapo-transpiration to the total amount of evaporation by atmometer through all growing periods, are 1.23 for early maturing variety, 1.25 for medium maturing variety, 1.27 for late maturing variety, respectively. 12) Only air temperature shows high correlation in relation between amount of evapo-transpiration and climatic conditions from the viewpoint of Korean climatic conditions through all growing periods of rice plants. 2. Amount of percolation 1) The amount of percolation for computation of planning water requirment ought to depend on water holding dates. 3. Available rainfall 1) The available rainfall and its coefficient of each period during the growing season of paddy fields are shown in Table 8. 2) The ratio (available coefficient) of available rainfall to the amount of rainfall during the growing season of paddy fields seems to be from 65% to 75% as the standard in Korea. 3) Available rainfall during the growing season of paddy fields in the common year is estimated to be about 550 millimeters. 4. Effects to be influenced upon percolation by transpiration of rice plants. 1) The stronger absorbtive action is, the more the amount of percolation decreases, because absorbtive action of rice plant roots influence upon percolation(Table 21, Table 22) 2) In case of planting of rice plants, there are several entirely different changes in the amount of percolation in the forenoon, at night and in the afternoon during the growing season, that is, is the morning and at night, the amount of percolation increases gradually after transplantation to the peak in the end of July or the early part of August (wast or soil temperature is the highest), and it decreases gradually after that, neverthless, in the afternoon, it decreases gradually after transplantation to be at the minimum in the middle of August, and it increases gradually after that. 3) In spite of the increasing amount of transpiration, the amount of daytime percolation decreases gadually after transplantation and appears to suddenly decrease about head swelling dates or heading-flowering period, but it begins to increase suddenly at the end of August again. 4) Changs of amount of percolation during all growing periods show some variable phenomena, that is, amount of percolation decreases after the end of July, and it increases in end August again, also it decreases after that once more. This phenomena may be influenced complexly from water or soil temperature(night time and forenoon) as absorbtive action of rice plant roots. 5) Correlation between the amount of daytime percolation and the amount of transpiration shows high negative, amount of night percolation is influenced by water or soil temperature, but there is little no influence by transpiration. It is estimated that the amount of a daily percolation is more influenced by of other causes than transpiration. 6) Correlation between the amount of night percoe, lation and water or soil temp tureshows high positive, but there is not any correlation between the amount of forenoon percolation or afternoon percolation and water of soil temperature. 7) There is high positive correlation which is r=+0.8382 between the amount of daily percolation of planting pot of rice plant and amount and amount of daily percolation of non-planting pot. 8) The total amount of percolation through all growin. periods of rice plants may be influenced more from specific permeability of soil, water of soil temperature, and otheres than transpiration of rice plants.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.3
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• pp.261-268
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• 1987

A green house experiment was conducted to find out the differences in the amount of biologically fixed nitrogen and kjeldahl nitrogen on the different soil texture, kinds and amounts of fertilizer nitrogen under light (photosynthetic $N_2$-fixation) and dark (heterotrophic $N_2$-fixation) condition in submerged paddy soil. The reults obtained were summarized as follows; 1. The amount of biologically fixed nitrogen per mg carbon from different organic matter was obtained as 0.13 mg in glucose, 0.09 mg in rice straw, and 0.07 mg in refused mushroom compost and barley straw under 60 days of incubation. 2. Nitrogen fixing activities were decreased with increase of fertilizer nitrogen and those tendency was pronounced more in sandy soil with application of urea than that of ammonium sulfate. 3. The application of ammonium sulfate in sandy soil under light condition was increased the photosynthetic $N_2$-fixation and the applied urea was remarkably reduced the heterotrophic $N_2$-fixation in sandy soil. The proportion of biologically fixed total nitrogen after experiment in sandy soil was obtained as 25% for dark(heterotrophic $N_2$-fixation) and 75% for light (photosynthetic $N_2$-fixation) condition. On the other hand, very similar biological $N_2$-fixing tendency was obtained between kinds of nitrogen fertilizer and two light condition in clayey soil. 4. The kjeldahl nitrogen was remarkably decreased after experiment under dark condition with application of urea than that of light condition with ammonium sulfate, and no remarkable decreasing tendency was obtained in clayey soil between two kinds of fertilizer nitrogen. 5. The high significant positive correlationship was obtained between calculated biological nitrogen fixation by acetylene reducing activity and kjeldahl nitrogen after experiment under light (y=0.8488X-5.9632, $r=0.9928^{**}$, n=21) and dark (y=0.8795X-7.1056, $r=0.9782^{**}$, n=21) condition. In this experiment condition, conversion factors of 6:1 was obtained from biological nitrogen fixation to soil nitrogen.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.363-370
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• 1984

In order to predict the possible fertilizer requirement from the K supplying capacity of soil, the relative K activity ratio, Kas/Kai and Gapon coefficients, KG. were determined for the soil samples before flooding and at heading stage of rice in pot experiment. These parameters assumed as the K supplying capacity of soils were discussed through correlation with other factors such as grain yields or the amounts of $K_2O$ uptake by the rice plant. The results may be summarized as follows: 1. The KGo values in soils before flooding were 7.8, 6.6, and 7.1, whereas the Kas/Kai values were 1.37, 1.26 and 2.11, respectively, in clay, loam and sandy loam soils. 2. The significant yield responses to the application of potassium fertilizer were observed whenever the KG values in soils at heading stage become larger to the original KG values, regardless of any levels of fertilizer application. 3. The linear correlations between the exchangeable cation ratios [Kex./(Ca+Mg) ex.:me/100g] in soils and the potassium activity ratios ($[K^+]/\sqrt{[Ca^{{+}{+}}+Mg^{{+}{+}}]}$: mole/l) in equilibrium solutions were observed with different linear gradients according to the soil properties. 4. The Kas/Kai in the soils, estimated prior to the experiment, showed high correlations with the grain yields or the amounts of $K_2O$ uptake in the all treatments, while the Kas/Kai and the KGo in the soils at heading stage showed high correlations with the grain yields or the amounts of $K_2O$ uptake in only N 15 Kg/10a treatments. 5. The Kas/Kai and the KGo values determined in the soil at heading stage of rice showed high negative correlation each other and they could be used as soil factors for predicting potassium fertilizer requirement.