• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.341-347
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• 1996

A green-house experiment was conducted to investigate the growth of Chinese cabbage, radish, and soybean and changes in soil chemical properties after application of 5 and 10mm of pH 2.7 simulated acid rain(SAR) followed by 0, 5, and 10mm of pH 6.0 normal water at the three-day intervals 20 times for Chinese cabbage and radish and 42 times for soybean. The results obtained are summarized as follows: 1. Visual damages by SAR were white-yellow leaf spots, dark brown or light green leaf color, and wrinkled leaf margins in all crops. The degree of visual damages was severer at 10mm than at 5mm SAR and it was reduced as the amounts of normal water increased after SAR application. 2. Chlorophyll content was higher at 10mm than at 5mm SAR application and increased as the amounts of normal water increased after SAR application in all crops. 3. Fresh weights of Chinese cabbage heads and radish roots and grain yield of soybean were higher at 10mm than at 5mm SAR, while they increased as the amounts of normal water increased at the same SAR level. 4. Changes in the mineral contents of plants were not consistent, while S content in radish and soybean increased as the amounts of SAR increased. 5. SAR lowered soil pH, while it increased soil N and S contents. Contents of soil organic matter, P, and exchangeable Ca, Mg, and K were not affected by the amounts of SAR.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.279-286
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• 2002

This pot experiment was conducted to find out the forage productivity and contents of mineral nutrients in an orchardgrass sward affected by the compost lime, and phosphorus applications on the newly reclaimed and arable pasture soils. This 2nd part was concerned with the effect of lime application(L$_{0}$=control, L$_1$=279, L$_2$=54g CaCO$_3$/pot). The results obtained are summarized as follows: 1. There were considerable differences between the newly reclaimed and arable pasture soils in the soil chemical properties as follows in general; poor/common in the newly reclaimed soil longrightarrow and common/good in the arable pasture soil in terms of soil fertility standard. 2. It was recognized that the lime application was resulted in somewhat decrease of the concentrations of available P$_2$O$_{5}$ and increase of P$_2$O$_{5}$ absorbtion coefficient in the newly reclaimed soil, whereas these negative effects were positively enhanced by both lime and compost applications. The concentrations of exchangeable Ca and mg in both soils were increased by lime application. 3. The vigour at early growth stage of orchardgrass was better in the arable pasture soil than newly reclaimed soil. It was worsened by the heavy lime application(L$_2$), but this negative effect was positively enhanced by both lime and compost application. 4. Compared with the non-lime application, the forage yields of L$_1$ treatment were increased in both soils by 15~18%. whereas it of L$_2$ treatment was similar or lower than it of L$_1$. 5. The concentrations of Ca, mg, and P in orchardgrass were relatively higher in the arable pasture soil than the newly reclaimed soil, whereas there it was no difference in the K concentration. It was recognized that the concentrations of mg and Ca in orchardgrass were higher in the L$_1$ treatment than the Lo treatment in both soils, whereas there were no difference in it between L$_1$ and L$_2$ treatments.ments.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.296-305
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• 2002

Rice yield and grain guality were investigated with treatments of silicate fertilizer, straw compost and NPK fertilizer in the paddy soil of silty clay loam from 1975 to 2001. Rice yield of the treatments of silicate fertilizer. $1,500kg\;ha^{-1}$ and straw compost $10,00kg\;ha^{-1}$ were increased by 15%, 10%, respectively, for 27years average yield in comparison with NPK plot. In the plots of NPK+silicate fertilizer $1,500kg\;ha^{-1}$, NPK+silicate fertilizer $2,500kg\;ha^{-1}$, taste value(Toyo instrument) of cooked rice and quality assessment were higher than those in NPK control plot and NPK+straw compost $10,000kg\;ha^{-1}$ plot, but the contents of crude protein, amylose of milled rice grain were lower than those in other treated plots. Nitrogen and phosphorous contents of rice plant were lower, but $SiO_2$ content were higher in the treatment of silicate ferti lizer 1,500, $2,500kg\;ha^{-1}$ than straw compost $10,000kg\;ha^{-1}$ plot. Rice quality assessment was positively correlated with taste value, but it was negatively correlated with crude protein and amylose content of milled rice grain. Ratios of Mg/N, $Mg/N{\cdot}K_2O$, $SiO_2/N$, $SiO_2/P_2O_5$ and $SiO_2/K_2O$ were positively correlated with taste value and quality assessment of rice grain, but negatively correlated with crude protein, amylose and fatty acid content. In soil chemical characteristics related with rice quality after experiment in 2001, soil pH and $SiO_2$ content were positively correlated with taste value and quality assessment of rice grain, but contents of soil $P_2O_5$, ex-K were negatively correlated with them.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.252-260
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• 2008

This study was conducted to observe the characteristics of mineral nutrient uptake of single-node cutting rose 'Versilla' and to determine optimal nutrient solution control method for soilless culture of 'Versilla' in a closed hydroponic system. Nutrient solution was managed by five different control methods: macro- and micro-element control in aeroponic system (M&M), macroelement control in aeroponic system (M), nutrient solution supplement in aeroponic system (S); electrical conductivity (EC) control in aeroponic system(EC-A); EC control in deep flow technique system(EC-D). The concentration of $NO_3$-N exceeds optimal range whereas P and Mg decreased at the later stage of plant growth with the EC control method, EC-A and EC-D. The overall mineral nutrient content increased with S. On the other hand the nutrient content at the root environment was maintained optimal with M&M and M. The nutrient solution control methods had significantly effect on the cut-flower quality. In the M&M and M, flower length, fresh weight and root activity were higher than those with the other mineral nutrients control methods. The maximal efficiency of photochemistry (Fv/Fm) was higher for M&M, M and S than that with EC-A and EC-D. Based on the above results, it is highly recommended to control nutrient solution by mineral nutrient control methods (M&M and M) in a closed hydroponic system for single-node cutting rose, 'Versillia'.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.234-239
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• 2009

This study aims to establish the directions for the optimal nutrient contents determined by soil and leaf analyses. The study is to be used as a source for basic information in investigating the effects of nutritional environment on ginseng growth at the fields of Ansung region in Gyeonggi province. The physical property of soil porosity is closely related to ginseng growth, with more than 50% of good growth in the field. The optimal range of chemical properties in soil was analyzed as 0.20-0.28% T-N, 500-900 mg/kg Av.P$_2$O$_5$, and 2.3-3.5 cmol$^+$/kg Exch.Ca. The optimal range of inorganic nutrient contents in leaves was also analyzed. P value was less than 0.25%, and Mg was more than 0.22%. Other elements were not found clearly. The ratios of N/P, N/Mg, K/Mg, and Ca/P of leaves with good growth in the field showed 10<, 10-13, <14, 1<, respectively. In addition, the Ca:Mg:K ratio of the Exch.cation (cmol$^+$/kg) may be useful as an indicator in the assessment of plant growth in ginseng.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.301-301
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• 2009

겨울철 농경지 이용율 제고 및 자연경관 조성을 위하여 녹비작물을 재배하는 면적이 지속적으로 증가하고 있는 추세이다. 그 동안 녹비작물에 대한 연구는 주로 파종적기, 작물에 대한 양분공급효과 및 타감 효과 등에 집중되어왔다. 본 연구에서는 토양 중 양분공급 및 미생물활성의 경시적 변화, 잡초억제 및 작물생육에 대한 녹비작물의 투입효과를 알아보기 위하여 수행하였다. 국립농업과학원 구내포장에서 2007년 9월 하순에 헤어리베치(8kg/10a)와 호밀(10kg/10a) 종자를 파종한 후, 이듬해 4월 하순에 수확하여 토양에 환원하였다. 질소공급량은 화학비료(15.2kgN/10a) 대비 헤어리베치(32.2kg/10a, 212%), 호밀(9.2kg/10a, 60%) 및 헤어리베치+호밀(15.5kg/10a, 102%)로 헤어리베치의 질소공급효과가 매우 높았다. 토양 무기태질소 함량은 녹비 처리 후 30일경에 최대에 도달하였으나, 호밀 처리구는 조사기간 동안 큰 변화가 없었다. 토양 유기물 함량의 변화는 시험 전(10DBI)과 비교하여 큰 차이를 보이지 않았으나, 녹비환원 후 10일경에 일시적으로 감소하는 경향을 보였는데 이는 녹비환원 후 토양경운에 의한 영향으로 판단되며, 무기태질소와는 달리 호밀처리구의 유기물함량이 지속적으로 증가하는 경향을 보였다. 토양 탄수화물(수용성 당)은 시험 전에 가장 높았으며, 시간의 경과와 함께 서서히 감소되는 양상을 보였으며 토양 미생물탄소 및 미생물질소의 양은 녹비처리구가 화학비료 처리구에 비해 높았으며 녹비환원 후 50일 까지는 증가하다가 그 이후에 감소하는 경향을 보였는데 이는 토양의 무기태질소 및 탄수화물과 밀접한 관계가 있는 것으로 판단되었다. 녹비처리 후 85일경에 잡초발생량을 조사한 결과, 화학비료 처리구에 비하여 헤어리베치 처리구는 40%, 호밀 처리구는 68%, 헤어리베치+호밀 처리구는 40%의 잡초억제효과가 있었다. 고추과의 수량은 화학비료 처리구(702kg/10a)>헤어리베치(694kg>10a)>헤어리베치+호밀(361kg/10a)>호밀(179kg/10a)의 순으로 나타났다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.198-205
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• 1982

In 1980, rice was considerably damaged by abnormal low temperature. In this paper, to determine the effect of low temperature on the growth and nutrition of rice, the experiment were carried out: varietal response to low temperature in the region with different elevations. Regional differences of heading response to low temperature were observed among varieties. The difference of days between regions were bigger in tongil lines than Japonica lines. Especially, Milyang 42 and Hangangchalbeo might belong the cold suceptible group, since the varieties were severely delayed their heading in the high mountainous region as comparred to plain region. The delay of heading with low temperature was brought out grain sterility, and fertility and ripening ratio is influenced cold tolerance and elevations, and it's decreased yield. Varieties with higher grain sterility by low temperature have higher total nitrogen content, but tended to have lower potassium and phosphate contents in the flag leaf. High content of total nitrogen, low contents of potassium and silicate were observed in the sterilized grain chaff an the opposite result were noted in the ferilized grain chaff at the ripening stage. The results reveal that the balance of these mineral element may play an important role in ripening and possibly cold tolerance.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.992-997
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• 2012

This study was conducted to get the basic information for absorb enhancement of accumulated soil nutrients in plastic film house. The grain sorghum (Sorghum bicolor L.) was sowing in plastic film house which soil nutrient accumulated moderately and was cutting at major growth period of sorghum. We were analyzed the regrowth pattern, biomass due to cutting time and amount of plant nutrient of grain sorghum. The obtained results were as follows. The heading date after cutting of sorghum in plastic film house was came to about 35 days. The accumulated of plant height were the longest as 379.4 cm in cutting at milk stage. The total biomass of sorghum in cutting at heading stage was 1.73 ton $10a^{-1}$ in cutting at heading stage. The high grain yields were produced with non-cutting and cutting at 10 leaves stage as 75~113 kg $10a^{-1}$ but the lowest grain yields were the cutting plots at booting stage as below 24 kg $10a^{-1}$. The content of nutrient in sorghum plant was low as progress of growth. The concentrations in aboveground sorghum due to plant parts was in order to leaves > panicle > stalk. The nitrogen content of sorghum was 0.6~0.7% in stalk, 1.5~1.6% in panicle and 1.8~2.3% in leaves. The amount of nutrient absorbed in sorghum was 4.2 kg $10a^{-1}$ in nitrogen, 1.7 kg $10a^{-1}$ phosphorus and 7.7 kg $10a^{-1}$ in potassium and the absorbing different by cutting time in order to booting > non-cutting > panicle formation ${\geq}$ milk ripe > 10 leaves stage.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.3
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• pp.247-253
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• 1985

In order to investigate the effects of water temperature on chemical properties of soil and nutrient uptake of rice plant, four varieties of rice were cultivated in a field where water temperature range was $17.3-23.0^{\circ}C$ and plant samples were taken at three growing stages and were analyzed in detail. The results were summarized as follows: 1. Organic matter content and pH of surface soil were showed no differences while the contents of $P_2O_5$ and $SiO_2$ were increased and potassium was decreased as the water temperature increased. 2. The amounts of nutrient uptake were related to the water temperature and the total nutrient contents of rice plants at harvesting stage were in order of $SiO_2$ > $K_2O$ > T-N > $P_2O_5$ > MgO. The rate of $SiO_2$/N and $K_2O$/N of rice plants grown at water temperature $23.0^{\circ}C$ were over two times to those of the water temperature $17.3^{\circ}C$. 3. Nutrient contents of rice plants showed a increasing tendency as increasing the water temperature. However, nutrient contents such as T-N at whole period, $P_2O_5$ at heading and harvesting stage, and $K_2O$ at heading stage were higher at low water temperature than those of high water temperature. 4. Most of nitrogen was translocated and accumulated in grain, potassium in straw respectively. All nutrients translocated to grain more easily as the water temperature increased.

• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.44-51
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• 2014

BACKGROUND: Water quality of rural areas are susceptible to agricultural nutrient input and supply such as chemical fertilizer and livestock manure. This study was conducted to evaluate the usefulness of nutrient (N and P) indices in understanding spatial variations of water quality across Chonnam province which is a typical agricultural region in Korea. METHODS AND RESULTS: The nutrient indices including chemical fertilizer supply, livestock manure production, and nutrient balance were correlated with water quality data (T-N, T-P, BOD, and COD) for the twenty-two districts of the province. Concentration of T-N were positively correlated with chemical fertilizer supply, livestock manure N production, and nutrient balance (P<0.05 or P<0.01). Meanwhile, T-P concentration was not correlated with these nutrient indices; however, there was a tendency that T-P concentration increases with livestock manure P production (P=0.06) and with nutrient balance (P=0.09). These results suggest that T-N concentration is susceptible to both chemical fertilizer and livestock manure; whereas T-P is likely to be affected by livestock manure rather than chemical fertilizer. The concentrations of BOD and COD were also positively (P<0.05 or P<0.01) correlated with livestock manure production. CONCLUSION: This study shows the usefulness of nutrient indices in understanding spatial variations of water quality and suggests that livestock manure rather than chemical fertilizer can be a more critical water pollution source and thus highlights the need for more attention to livestock manure treatments for rural water quality management.