• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.25-34
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• 1979

To clealify the cause of barley and wheat sterility that occurred 77 / 78 cultivation period in Yeongnam area, a few environmental conditions were analyzed. The results are summarized as follows; 1. During the important growing stages such as meiosis and heading stages of barley encountered with severe droughtiness and unusual low temperature. 2. Soil moisture contents in the double cropping paddy soils were higher than cultivated uplands, and in the subsoils than the surface soils, in the clay soils than the sandy soils, in the northern aspect than the southern aspect of slope, respectively. 3. The sterilizing percentage of barley in the double cropping paddy fields were lower than cultivated uplands, in the alluvial fans and plains were lower than cultivated uplands, in the alluvial fans and plains were lower than in rolling or in foot slopes and the northerm aspect of slopes were lower than southern aspect. 4. The sterilizing percentage in the sandy soils were higher than clay soils and in the soils that have shallower plowing layer and shallower available depth had higher sterility. 5. The sterilizing percentage of barley had negative correlation with soil moisture contents in the surface and subsoils in both of cultivated upland or double cropping paddy fields. 6. The droughtiness that prevailed over reproductive growing stages of barley might be cause the sterility and the severe coldness also could be accelerate the phenomenon.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.520-529
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• 2017

In Korea, the largest agricultural lands are paddy fields which have poor infiltration and drainage properties. Recently, Korean government pursuits cultivating upland crops in paddy fields to reduce overproduced rice in Korea. In order to succeed this policy, it is critical to set criteria suitability classification for upland crops cultivating in paddy field soils. The objective of this study was developing guideline of suitability classification for sesame cultivation in paddy field soils. Yields of sesame cultivated in paddy field soils and soil properties were investigated at 40 locations at nationwide scale. Soil properties such as topography, soil texture, soil moisture contents, slope, and drainage level were investigated. The guideline of suitability classification for sesame was determined by multi-regression method. As a result, sesame yields had the greatest correlation with topography, soil moisture content, and slope. Since sesame is sensitive to excessive soil moisture content, paddy fields with well drained, slope of 7-15% and mountain foot or hill were best suit for cultivating sesame. Sesame yields were greater with less soil moisture contents. Based on these results, area of best suitable paddy field land for sesame was 161,400 ha, suitable land was 62,600 ha, possible land was 331,600 ha, and low productive land was 1,075,500 ha. Compared to existing suitability classification, the new guideline of classification recommended smaller area of best or suitable areas to cultivate sesame. This result may suggest that sesame cultivation in paddy field can be very susceptible to soil moisture contents.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.35-41
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• 1979

A study was conducted to investigate the status of organic phosphorus in soils originated from different parent materials and under different uses(Virgin, rice soil, upland). The results are summarized as a following. 1. Regardless of parent materials and land uses, the contents of different forms of organic phosphorus are in the order of unidentified organic-P>Inositol-P>Sugar-P>Lipid-P. 2. In case of Inositol-p, the contents were in the order of rice soil>upland>virgin soil. 3. The contents of Sugar-P and Lipid-P in cultivated soils are higher than in uncultivated soil. 4. RNA and DNA are not identified in any soil when detected by ultra-violet absorption method. 5. There is highly significant correlation between the content of soil organic matter and that of organic phosphate. However, there is remarkable difference in the pattern of correlation between cultivated soils and uncultivated soils. 6. Comments were made on the factors on plant availability of various organic phosphorus.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.720-730
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• 2016

Greenhouse-gas emission factors are widely used to estimate emissions arising from a defined unit of a specific activity. Such estimates are used both for international reporting to the United Nations Framework Convention on Climate Change (UNFCCC) and for myriad national and sub-national reporting purposes (for example, European Union Emissions Trading Scheme; EU ETS). As with the other so-called 'Kyoto protocol GHGs', the Intergovernmental Panel on Climate Change (IPCC) provides a methodology for national and sub-national estimation of $N_2O$ emissions, based on the sector from which the emissions arise. The objective of this study was to develop a integrated emission factor to estimate the direct $N_2O$ emission from an agricultural field cultivated with the red pepper, soy bean, spring cabbage, autumn cabbage and potato in 2010~2012. Emission factor of $N_2O$ calculated using accumulated $N_2O$ emission, N fertilization rate, and background $N_2O$ emission over three year experiment was $0.00596{\pm}0.001337kg$ $N_2O-N(N\;kg)^{-1}$. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.179-188
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• 2014

This research reports the effects of shifting cultivation on soil environment collecting samples from 0-5 cm soil depth from five locations viz. at Burburichhara, Maichchari, Longadu, Sukurchhari and Muralipara in Rangamati district of Chittagong Hill Tracts (CHTs). Soil analyses showed that fungal and bacterial population, microbial respiration and active microbial biomass, maximum water holding capacity, conductivity and moisture contents were significantly (at least $p{\leq}0.05$) lower in shifting cultivated soil compared to adjacent mixed tree plantations at all the sites. On an average in soils of 5 different shifting cultivated lands fungal population was $1.33{\times}10^5$ CFU/g dry soil and bacterial population $1.80{\times}10^7$ CFU/g dry soil and in mixed plantations fungal population was $1.70{\times}10^5$ and bacterial population $2.51{\times}10^7$ CFU/g dry soil. Organic matter and exchangeable Ca and Mg contents were significantly (at least $p{\leq}0.05$) lower and bulk density significantly (at least $p{\leq}0.05$) higher in shifting cultivated land in most of the locations compared to adjacent mixed tree plantations. Ratios of microbial respiration and organic carbon as well as active microbial biomass and organic carbon were distinctly lower and pH higher at 3 locations in shifting cultivated soils compared to mixed plantations. Findings of various soil properties, therefore, suggest that shifting cultivation has deteriorating effects on soil environment.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.281-286
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• 1990

Field experiments were conducted to avail the accumulated phosphorus by silica 200kg/10a and compost 2,000kg/10a instead of phosphate fertilization in 1988 to 1989. Cultivated varieties were Dongjinbyeo in paddy soils of Av. $P_2O_5$ 233ppm, and Baegunkong in upland soils of Av. $P_2O_5$ 530ppm. The results were as follows. 1. Available phosphorus in the soil was increased about 60ppm in silica and compost application compared with control. Its increment rate by silica and compost application was higher in paddy soils than in upland soils. 2. Absorbed phosphorus by plant was increased in silica and compost application compared with control, whose difference was higher in soybean plant than in rice plant. 3. Amount of absorbed phosphorus in plant was negative in relation to soil DTPA-Fe, but was positive in relation to soil reduction and root nodule of soybean. 4. Persistence rate of phosphorus was about 80 percent in compost application and 100 percent in phosphate fertilization compared with control, and it was apt to decrease by silica. 5. The yield of rice was no difference between with and without phosphate fertilization, but the yield of soybean was increased 5 percent in none application compared with phosphate fertilization.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.119-123
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• 2019

BACKGROUND: Estimation of soil nitrogen supply is essential to manage nitrogen fertilization in arable land. In Korea, nitrogen fertilization is recommended based on the soil organic matter content because it is difficult to assess nitrogen (N) mineralization of upland soils directly. In this study, the relationship between soil organic matter (SOM) content and N mineralization was investigated to explore the limitation of using SOM in predicting soil N mineralization. METHODS AND RESULTS: Soil samples from the 0 to 10 cm depth were collected from 18 individual pepper cultivated fields in Tae-an and Chung-yang provinces before fertilization. N mineralization in the soils was quantified using incubation for 70 days at $30^{\circ}C$. The mineralizable soil N (MSN) was positively correlated with SOM, and the relation equation between MSN and SOM was '$MSN(kg\;10a^{-1})=0.2933{\ast}SOM(g\;kg^{-1})+0.0897$ ($r^2=0.6224$, p<0.001)'. However, the differences of N mineralization among the soils with the similar concentrations of soil organic matter were about 3 to 4.6 times, suggesting that the other soil factors such as total N concentration or EC should affect N mineralization. CONCLUSION: We concluded that SOM alone could not reflect the capacity of soil to supply N that is used for recommendation of N fertilization rate. Therefore, other soil properties should be considered to improve N fertilization management in arable land for sustainable agriculture.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.1-8
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• 1998

To compare different methods for the determination of available soil P in the relationship between the soil P and plant uptake of P, rice and corn were cultivated in the pot filled with soils of different available P contents. The soils were taken from 20 rice fields and 20 upland soils. The available soil P were determined before the experiment by Olsen, Lancaster, Bray 1, Bray 2, Mehlich II and Calcium lactate methods and the correlations between the available soil P measured by different methods and the amount of P taken up by corn at 10 leaf stage and by rice at maximum tillering stage were investigated. In upland soils, the available P measured by all the methods was linearly regressed with high significance to the amount of P taken up by corn. The coefficients of determination($R^2$) in the regression equations ranged from 0.596(Calcium lactate method) to 0.891(Olsen method). In rice soils, the soil available P did not regressed by first-order to the amount of P taken up by rice plant, while Michaelis-Menten equation better explained the relationship between the two parameters. In the Michaelis-Menten equation the coefficients of determination for each analytical method ranged from 0.607(Mehlich II method) to 0.923(Lancaster method). Based upon these observations it is concluded that for testing of available P for corn soils Olsen, Bray 2 and Lancaster methods are equally superior to other methods. For rice soils Lancaster, Bray 1, and Bray 2 methods are better than others.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.188-196
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• 2020

BACKGROUND: In order to cultivate upland crops in reclaimed land, economically appropriate crops should be selected. Jerusalem artichoke (Helianthus tuberosus L.) is one of the primary sources for inulin in higher plants. The objective of this study was to evaluate and compare growth and inulin of H. tuberosus L. according to the cultivation region in Korea. METHODS AND RESULTS: 21 varieties of H. tuberosus L. were collected in Korea, and then 7 varieties of H. tuberosus L. were selected for this study. To compare growth and inulin, those varieties were cultivated in reclaimed land and upland soils. The growth of H. tuberosus L. significantly decreased when cultivated in reclaimed land. There was an increas at 17.8% in the content of white H. tuberosus L. tuber inulin in reclaimed land. CONCLUSION: The content of inulin in H. tuberosus L. tubers was found to be dependent on cultivation region and tuber color. There was a difference of the inulin content between the tubers with different colors in reclaimed land. Purple tubers of P20 were considered suitable varieties for cultivation in reclaimed land. White tubers of W1 and W8 were also considered suitable varieties for cultivation in reclaimed land.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.48-54
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• 2011

This study was performed to analyze the possibility of using Korean native Aster koraiensis Nakai for phytoremediation at various fields. A. koraiensis was cultivated at paddy, upland and forest soils contaminated with heavy metals. After 8 weeks of cultivation, and growth and its absorbing capacity of heavy metals were analyzed. The results showed that A. koraiensis was grown well even at the soil highly contaminated with heavy metals, which means it has a tolerance to heavy metals. As analysis results of arsenic, cadmium, copper, lead and zinc contents absorbed from various soils contaminated with heavy metals, heavy metal absorbing capacity of A. koraiensis was depending on the heavy metal contents in the soils and soil property. In case of arsenic, cadmium and copper, heavy metal accumulation capacities of Aster koraiensis were much influenced by contents of heavy metals in the soils. Absorbing capacity of plants was increased when heavy metal contents in the soils were high. Lead absorbing capacity was depending more on soil property than lead contents in the soil, and was great at sandy soil of forest. Zinc absorbing capacity was influenced by both soil properties and Zn contents in the soil, was increased at paddy soil contaminated with high concentrations of heavy metals and upland soils. In general, A. koraiensis had a tolerance to heavy metals and showed great absorbing capability of heavy metals. So A. koraiensis can be used as a good landscape material for phytoremediation at various soils contaminated with heavy metals.