• Korean Journal of Soil Science and Fertilizer
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• v.26 no.3
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• pp.181-188
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• 1993

The effects of paddy-upland rotation and cropping system on the mineralization of soil organic nitrigen, on the change of organic matter and available phosphorus content in the soil, and on the rice yield and nutrients absorption were studied in Seokcheon fine-sandy loam soil. 1. In the incubation test mineralzed soil nitrogen and the nitrogen extracted by pH 7 phosphate buffer solutions were higher in the soils from every and two year rotation systems than continuous rice cultivation. In terms of cropping system potato-chiness cabbage-rice increased them more than soybean-rice system. 2. The change of soil organic matter and available phosphorus contents were not much in continuous rice cultivation, while in rotation system they decreased as the paddy-upland rotation frequency decreased. In terms of cropping system they decresed more in potato-Chinese cabbage-rice system compared with soybean-rice systems. 3. The rice yield was higher in the paddy-upland rotation system than that of continuous rice cultivation. However, the effects were decreased gradually every year, as shown by 26~20, 17~5, and 5~4% yield increase for first, second, and third year, respectively, in potato-Chinese cabbage-rice and soybean-rice system compared with continuous rice cultivation. 4. All the absorbed nutrient contents increased in every and two year rotation system compared with continuous rice cultivation. In terms of cropping system potato-Chiness cabbage-rice system increased them more compared with soybean-rice system.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.95-105
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• 2020

BACKGROUND: In this study, in order to verify the effects of supplemented organic amendment fertilizers recommended by the soil testing on cabbages, we used various amounts of organic amendment fertilizers. The amount of organic amendment fertilizers was decided by calculating each ratio of inorganic nitrogen, phosphorus, and potassium based on the recommended fertilizer composition. METHODS AND RESULTS: The cabbages subjected to treatments 1 and 2 showed similar or greater leaf colors (SPAD values), head heights, head widths, head weight, soil organic matter content, nitrate-nitrogen level, and conductivity after harvest, when compared with cabbages treated with chemical fertilizers. The phosphorus and potassium fixation in the soil were higher in the plot where cabbages were treated with chemical fertilizers, and the nutrient use efficiency was greater in the plots with organic amendments and mineral addition. CONCLUSION: The treatments 1 and 2 that were supplemented with 180-200% of nitrogen, 100-130% of phosphorus, and 185-250% of potassium in comparison to chemical fertilizers, applied by the inorganic ratios of nitrogen, phosphorus, and potassium can be used as organic amendment fertilizers for cabbages.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.50-55
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• 1986

To get the basic information about ginseng seedling production, yields of ginseng seedling and soil physico-chemical components in 32 fields of Yang-Jik and 19 fields of Ban-Yang-Jik nursery were investigated. Germination rate is $78.5{\pm}3.0%$, $77.8{\pm}2.8%$ in Yang-Jik and Ban-Yang-Jik. Rate of number of mature seedlings to number of seeds planted is $62{\pm}13.5%$, $53{\pm}12.6%$ in Yang-Jik and Ban-Yang-Jik. Rate of number of available seedlings to number of seeds planted (Rate of available seedling) is $42{\pm}12.5%$, $26{\pm}12.1%$ in Yang-Jik and Ban-Yang-Jik. The number of available seedlings per Kan (Kan means $180{\times}90cm$ area) is $627{\pm}187$, $368{\pm}182$ in Yang-Jik and Ban-Yang-Jik. Rate of number of unusable seedlings to number of mature seedlings is 34%, 51% in Yang-Jik and Ban-Yang-Jik. It showed the negative correlation between amount of coarse sand and stem height, and central leaf length, on the other hand, possitive correlation between amount of extremely fine sand, and stem height, and central leaf length respectively. Rate of available seedling was positively correlated with amount of medium, fine and extremely fine sand, whereas negatively correlated with amount of coarse sand in Yang-Jik. Root weight per seedling was positively correlated with amount of medium, fine and extremely fine sand. Contents of organic matter, available phosphate and potassium in Ban-Yang-Jik were higher than those of Yang-Jik, but content of lime was higher in Yang-Jik compared to that of Ban-Yang-Jik. Possitive correlations were showed between leaf area per seedling and content of organic matter, and between stem height and content of lime in Yang-Jik. Root weight per seedling was positively correlated with content of organic matter and magnesium in Ban-Yang-Jik, but there is no correlation between any of soil chemical components and root weight in Yang-Jik.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.96-106
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• 1998

Rice plants were grown for 42 days in the specially made micro-ecosystem(pot) containing two different soils treated with fresh and 60-day-aged residues of [$^{14}C$]quinclorac, respectively, to elucidate the behaviour of the herbicide quinclorac residues in the soils. Amounts of $^{14}CO_{2}$ evolved from two soils treated with different residues with and without vegetation were all less than 2.2% of the total $^{14}C$, indicating that there was little microbial degradation of quinclorac in soil. $^{14}C$-Radioactivity absorbed and translocated into rice plants from soil A and B containing fresh quinclorac residues was 8.4 and 24.2%, respectively, of the originally applied $^{14}C$, while 5.5 and 17.7%, in aged residue soils. These results indicate that larger amounts of $^{14}C$ were absorbed by rice plants from soil B with less organic matter and clay than soil A, and the uptake of [$^{14}C$]quinclorac and its degradation products decreased with aging in soil. After 42 days of rice growing, 84.5 and 61.8% of the $^{14}C$ applied freshly to soil A and B, respectively, remained in soil, whereas, in the case of aged soils, 86.3 and 67.7% of the $^{14}C$ applied did. Meanwhile, without vegetation, more than 98.3% of the $^{14}C$ applied, in both fresh and aged residues, remained in soil, suggesting that quinclorac was relatively persistent chemically and microbiologically. Most of the non-extractable soil-bound residues of [$^{14}C$]quinclorac were incorporated into the organic matter and largely distributed in the fulvic acid portion.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.332-338
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• 2010

Degradation characteristics of insecticide diazinon in upland and paddy soils under laboratory conditions were investigated to elucidate the effect of raw pig slurry (RPS) and processed pig slurry (PPS) treatment. Soil (20g) was treated with RPS and PPS by standard rate, double rate and triple rate before treating with diazinon (0.5mg/kg level) and incubating at ($25{\pm}2^{\circ}C$) for 60 days. The half-lives of diazinon in the untreated upland and paddy soil were about 28 and 22 days respectively. The degradation rate of diazinon was faster by $5.0{\pm}1.2$ days in the paddy soil than in the upland soil independent of fertilizer types. This result indicates that soil moisture content affects the half-life of diazinon probably by hydrolysis. Degradation of diazinon was faster in RPS treatment soil than in PPS treatment soil. The more amount of fertilizers were treated, the more rapidly diazinon degraded regardless of fertilizers and soil types. Based on the results obtained, degradation of diazinon in soil was definitely influenced by soil water contents and treatment of those fertilizers.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.1-6
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• 1983

The results of COLE(Coefficient of Linear Extensibility) measurement on various paddy soils in Korea are summarized as follows; 1. The COLE values of paddy soil in Korea varied from 0.024 to 0.094 in the surface soil while in the sub-surface soils those were ranging from 0.022 to 0.115. The poorer the relative drainage and the finer the texture caused, the greater the COLE values. 2. The matured clayey soils on fluvio-marine plains and local alluvium derived from the Tertiary materials have COLE values more than 0.09 which is demonstrated that the necessity of COLE measurement throughout profiles so that could be considered the characteristic in the characteristic of those soils. 3. The clay content has the highest positive correlation (r=0.81~0.76) values. The content of organic matter, water content at 1/3 bar, Atterberg limits, water stable aggregate etc. also have significant positive correlation with COLE values while the context of sand and silt show negative correlation. 4. Although the COLE values measured on horizontal linear bases were slightly greater than those measured on volume bases practicability was for granted. For more accurate measurement of COLE, it is reasonable to have the average values of COLE calculated from the horizontal and vertical bases.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.337-344
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• 1999

This study was carried out to investigate the influence of spa sewage on water quality and chemical contents in the paddy soil along stream from 1997 to 1998. Concentration of $PO_4, SO_4, Cl, NH_{4}, Ca, Na$ and COD in the spa sewage were lower than standard for agricultural usage, and were lowered as the sewage flew to the into stream. The concentration of $SO_4$in spa sewage was over the criteria for agricultural usage in the inlet, but was lower than criteria for agricultural usage by inlet of non polluted stream water. Concentration of pollutants in the sediment of water channel were the highest in the inlet site. There were no pollutants accumulation in the paddy soil where spa sewage was irrigated. It may be resulted from nutrients uptake of rice plant and self purification of paddy soil. On the while, considering electric conductivity and nitrate in spa sewage, this results suggest that long-term irrigation of the spa sewage may be required general management with some decreasing fertilization.

• Korean Journal of Organic Agriculture
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• v.23 no.3
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• pp.509-522
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• 2015

Organic ginseng farming has rapidly increased in response to consumer demand for a safe product which improves health. Differences in soil nutrient concentration and ginsenoside content between organic and conventional ginseng farming have, however, not yet been properly studied. Therefore the aim of the present study was to compare soil nutrient concentration and ginsenoside content between these two farming systems. $NO_3-N$, $P_2O_5$, and K were significantly different between organic and conventional ginseng farming. The total content of ginsenoside and individual ginsenoside components were higher in organically grown ginseng than in ginseng from conventional farming, although there is no significant difference. Particularly, protopanaxadiol saponins were higher than protopanaxatriol saponins in ginseng from organic farming compared to ginseng produced by conventional farming. $NO_3-N$ content in soils showed a negative correlation with the content of ginsenosides $Rb_2$ and Rd. In addition, $P_2O_5$ showed a negative correlation with ginsenosides $Rb_1$, Rc, and PD/PT ratio. Organic matter showed a positive crrelation with ginsenosides Re. To increase the ginsenoside content of ginseng, we recommend increasing organic matter and decreasing $NO_3-N$ and $P_2O_5$ contents in the soil.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.421-426
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• 1999

Species composition, species diversity, standing biomass and soil properties of the grasslands, which are developed in the vicinity of Yoch’on Industrial Complex, were investigated. The grassland divided into three types, mugwort (Artemisia princeps var. orientalis) community, porkweed (Phytolacca americana) community and eulalia (Miscanthus sinensis) community by physiognomy Standing biomass of mugwort community, porkweed community and eulalia community was 5,645 g/$m^2$, 2,827 g/$m^2$ and 9,048 g/$m^2$, respectively. Species diversity of mugwort community, porkweed community and eulalia community was 1.03, 0.54 and 0.26, respectively. Total N, available P, total S and soluble S of the top soil in this grassland were much higher than those in other areas. Most of the species in this grassland are indicator species of soil eutrophication.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.341-344
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• 1997

To check the possibility to use the pharmaceutical by product of ginkgo leaf for the improvement soil fertility, a pot experiment was conducted with paddy rice. There were three treatment; NPK alone, NPK+7000kg(air dry)/ha of ginkgo leaf waste and NPK+700 kg of water-washed ginkgo leaf waste (air dry)/ha. The result indicated that the application of ginkgo leaf waste severely retarded the growth of rice. Water washing did reduce the severity of retardation, but the water washed ginkgo leaf waste also retarded the growth of rice significantly. The result of this study suggested that ginkgo leaf waste may contain some growth inhibiting substance.