• Title/Summary/Keyword: Absorption Ratio

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Development of Nutrient Solution for Hydroponics of Cruciferae Leaf Vegetables Based on Nutrient-Water Absorption Rate and the Cation Ratio (양수분 흡수율과 양이온 비율에 의한 배추과 엽채류 수경 배양액 개발)

  • Choi Ki Young;Yang Eun-Young;Park Dong-Kum;Kim Young Chul;Seo Tae Cheol;Yun Hyung Kweon;Seo Hyo Duk
    • Journal of Bio-Environment Control
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    • v.14 no.4
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    • pp.289-297
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    • 2005
  • This study was conducted to develop the suitable nutrient solutions for variable Cruciferae leafy vegetables. l/2, 1 and 3/2 strength of nutrient solution recommended by National Horticultural Research Institute were supplied to plants in deep flow technique systems during 25 days. The growth of pak-choi and leaf mustard 'Asia curled' was highest in the 3/2 strength, and kaie 'TBC' in the 1 strength. Mean cation ratio of nutrient solution for pak-choi, leaf mustard and kale was K $49.5\%$, Ca $35.8\%$ and Mg $14.7\%$, which was obtained by calculating the uptake rates of water and nutrients. Suitable composition of the nutrient solution for Cruciferae leafy vegetables was N 14, P 3, K 6.8, Ca 4.8, $Mg 2m{\cdot}L^{-1}$. To examine the suitability of nutrient solution developed for Cruciferae vegetables (NSC), plants were grown 4 times from Sep. 2003 to Oct. 2004. When plants were grown in NSC, relative growth rate increased 1.1 to 2.5 times and vitamin C content 1.06 to 1.52 times. The proper plants to apply NSC for functional leaf vegetable production were leaf mustard 'Asia recurled', 'Redcurled' and 'Pamagreen', kale 'TBC', 'Portugal' and 'Hanchu collard', leaf broccoli 'New green', pak-choi, baby cabbage 'Red king' and 'Green king', flowering red chinese cabbage and Korean cabbage.

Effects of Combined Application of Micronutrients on these Total and Relative Contents, Uptake Amounts, and Mutual Ratios in Orchardgrass and White Clover (Orchardgrass 및 White clover의 단파 및 혼파 재배에서 미량요소(Fe, Mn, Cu, Zn, Mo, B)의 조합시비가 목초의 총 함량, 상대 함량, 탈취량 및 상호비율 변화에 미치는 영향)

  • Jung, Yeun-Kyu
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.24 no.2
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    • pp.93-104
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    • 2004
  • This pot experiment was conducted to investigate the effects of combined micronutrient application($T_1$; control, $T_2$; Fe, $T_3$; Fe+Mn, $T_4$; Fe+Mn+Cu, $T_5$ ; Fe+Mn+Cu+Zn, $T_6$ ; Fe+Mn+Cu+Zn+Mo, T$_{7}$; Fe+Mn+Cu+Zn + Mo + B) on forage performance of pure and mixed cultures of orchardgrass and white clover. The fifth part was concerned with the changes in the total and relative contents, uptake amounts, and mutual ratios. of micronutrients in forages. The results obtained are summarized as follows: 1. The relative contents(total contents of 6 micronutrients = 100%) of Fe and Mn were considerably influenced by the antagonism between Fe and Mn, and also were influenced by the differences in Mn-absorption between orchardgrass and white clover. Compared with pure culture, orchardgrass showed high relative contents of Mn, and low relative contents of Fe and B in mixed culture. White clover, however, tended to be exactly opposed to the above trends. In relative contents, the T$_6$ 6/ resulted generally in decrease of Fe. However the $T_7$ resulted in increase of Mn and B. In addition, the $T_7$ resulted in decrease of Cu and Zn in orchardgrass, and Mo in white clover. 2. In general, there were differences in the tendency between the yield changes and the uptake amounts of micronutrients. General differences have been showed in the uptake amounts and mutual ratios of micronutrients based on the forage species, pure/mixed culture, additional fertilization, and antagonism. The uptake amounts of total micronutrients were generally increased by the treatments with increased combination. In uptake amounts, the $T_7$ resulted in the increase of Mn and B, and decrease of Mo. 3. The mutual ratios of Fe/Mn, Fe/Cu, and Mn/Cu were considerably influenced by the antagonism between Fe and Mn. At the $T_7$ , very low ratio of Fe/Mo affected by the T6 tended to be somewhat improved because of the decrease of Mo content. The poor growth of forages at the $T_6$ was improved by the $T_7$ . This fact was likely to be caused by the adequate B/Mo ratio.

Synchronized Synergism Using Ethanol, L-lysine and $NaBH_4$ Glutaraldehyde Treated Porcine Pericardium (글루타르알데하이드 고정 돼지 심낭에서 Ethanol, L-lysine, $NaBH_4$ 병합 처치시 상승효과)

  • Kim, Kwan-Chang;Kim, Yong-Jin;Kim, Soo-Hwan;Choi, Seung-Hwa
    • Journal of Chest Surgery
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    • v.42 no.6
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    • pp.685-695
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    • 2009
  • Background: Calcification is the most frequent cause of clinical failure of bioprosthetic tissues that are fabricated from Glutaraldehyde (GA)-fixed porcine valve or bovine pericardium. We recently used a multi-factorial approach of employing different mechanisms to investigate how to reduce the calcification of bioprosthetic tissues. The purpose of the present study was to evaluate the synchronized synergism using ethanol, L-lysine and $NaBH_4$ in glutaraldehyde treated porcine pericardium from the standpoint of calcification and tissue elasticity. Material and Method: Porcine pericardium was fixed with 0.625% GA (commercial fixation). An interim step of ethanol (80%; 1 day at room temperature) or L-lysine (0.1 M; 2 days at $37^{\circ}C$) or $NaBH_4$ (0.1 M; 2 days at room temperature) was followed by completion of the GA fixation (2 days at $4^{\circ}C$ and 7 days at room temperature). The tensile strength and thickness of the samples were measured. The treated pericardiums were implanted subcutaneously into three-week old Sprague-Dawley rats for 8 weeks. The calcium content was assessed by atomic absorption spectroscopy and the histology of the samples. Result: The amount of calcium in the pericardium pretreated with ethanol (13.6${\pm}$10.0 ug/mg, p=0.008), L-lysine (15.3${\pm}$1.0 ug/mg, p=0.002) and both (16.1${\pm}$11.1 ug/mg, p=0.012) was significantly reduced compared with the control (51.2${\pm}$8.5 ug/mg). However, $NaBH_4$ pretreatment (65.7${\pm}$61.8 ug/mg, p=0.653) and combined pretreatment that including ethanol, L-lysine and $NaBH_4$ (92.9${\pm}$58.3 ug/mg, p=0.288) were not significantly different from the controls(51.2${\pm}$8.5 ug/mg). Both the combined pretreatment using ethanol and L-lysine (7.60${\pm}$1.55, p=0.76) and the combined pretreatment that included ethanol, L-lysine and $NaBH_4$ (7.47${\pm}$1.85, p=0.33) increased the tensile strength/thickness ratio compared with that of the controls (4.75${\pm}$1.88). Conclusion: The combined pretreatment using ethanol and L-lysine seemed to decrease the calcification of porcine pericardium fixed with glutaraldehyde, as compared to single pretreatment, and it increase the tissue elasticity, but to the degree that showed synchronized synergism. $NaBH_4$ pretreatment seemed to increase the calcification of porcine pericardium, irrespective of whether single or combined pretreatment was used.

Effect of Application Time and Rate of Mixed Expeller Cake on Soil Environment and Rice Quality (혼합유박 시용량 및 시용시기가 토양환경과 미질에 미치는 영향)

  • Yang, Chang-Hyu;Yoo, Chul-Hyun;Kim, Byeong-Su;Park, Woo-Kyun;Kim, Jae-Duk;Jung, Kwang-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.2
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    • pp.103-111
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    • 2008
  • This study was carried out to investigate the optimal application rate and time of mixed expeller cake (MEC) for the replacement of chemical fertilizer. Dongjin-1, as cultivated rice was used at Fluvio-marine deposit in Honam plain paddy field. Soil chemical properties were improved by the application of MEC. Contents of total nitrogen and organic matter were higher in 70%, 100% plots of basal dressing than standard fertilizer application (SFA) plot. Cation exchangeable capacity was highly increased in 70% plot of basal dressing. Also, the content of organic matter in soil was increased with MEC application. Cation exchangeable capacity, total nitrogen and available phosphate were decreased according to late application time. The content of inorganic nitrogen in soil showed high tendency at more application rate of MEC, and nitrogen mineralization at harvest season have finished in 50%, 70% plots of basal dressing. The content of inorganic nitrogen in soil was increased according to late application time, however it was decreased in the late period of growth. Leaf color value became darker with increased application rate of MEC. Leaf color was dark green in MEC application plots at panicle formation stage, on the other hand, it was light green in 50%, 70% plots of basal dressing at heading stage. SPAD reading value of leaf-color was high during the whole growth stage in MEC application plots. More application rate of MEC showed higher tendency of fertilizer nitrogen absorption. Nitrogen use efficiency was the highest in 70% plot of basal dressing. Absorbed amount of fertilized nitrogen was increased in 10~15days before transplanting and nitrogen use efficiency was high according to the late application time. The ratio of perfect kernel and the content of protein on hulled rice showed high tendency at the less application rate of MEC. The ratio of head rice on milled rice showed high tendency at the less application rate of MEC. Rice yield increased 4% in 100% and 70% plots of basal dressing compare with SFA ($5.18Mg\;ha^{-1}$) plot respectively. Ear and culm length of rice were long according to the late application time, while the numbers of spikelet and ear were increased and the percentage of ripened grain was decreased. Rice yield was increased 2~5% in all MEC application plots compared to SFA plot and especially, increased 10~15days before transplanting in application plots. The optimal application rate and time of MEC on normal paddy field in plain were concluded that 70% basal dressing and 10~15days before transplanting

Studies on the Foliar Application of Urea as Nitrogen Source of Rice Plant Nutrition (요소엽면살포(尿素葉面撒布)에 따른 수도(水稻)의 질소영양(窒素營養)에 관(關)한 연구(硏究))

  • Cho, Seoung-Jin
    • Applied Biological Chemistry
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    • v.9
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    • pp.125-147
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    • 1968
  • This experiment was carried out as a part of the studies on reasonable application of nitrogen in rice plant to determine: (I) Nitrogen absorption. and rooting of rice seedlings as affected by urea foliar application at late seedling stage (II) Effect of leaf prunning and foliar application of urea at late heading stage on the maturation and yield of rice (III) Effect of foliar application of urea and its time during the stage of ear formation on yield of rice plant. Results obtained are summarized as follows. Exp.I: Nitrogen absorption and rooting of rice seedlings as affected be urea foliar application at late seedling stage. 1 : The foliar application of urea plots$(T_{1},T_2)$ snowed mare N-content than non-urea foliar application plot(T0) at lane seedling stage, being significant among treatments and foliar application of urea seemed more effective in increasing the N-content of seedlings. and promoted root settlement and early growth alter the transplanting. 2 : The carbon contents of the plants of $T_1$, and $T_2$ at late seedling stage increased than T0, and the carbon contents. of $T_1$ and $T_2$ plots became higher in amount in proportion to the nitrogen absorption as compared with those of $T_0$. 3 : C/N ratio appeared significant among soil application plots($N_1, \;N_2$) and foliar application of urea plots ($T_1$, $T_2$ and $T_0$). C/N ratio was lower in case of increased amount of nitrogen. The higher contents of nitrogen and carbon and lower C/N ratio resulted in the increment of root numbers and root lengths. Exp.II: Effect of leaf prunning and foliar application of urea at late heading stage on the maturation and yield of rice. 1 : There was a highly significant decrease in the maturing rate by severe leaf prunning. In the mean time, significant increase in maturing rate was observed with urea foliar application and it was found the more frequent application the more effective for higher maturing rate with a moderate significance. A correlationship between the level of prunning and maturing rate was enumerated to 0.961 of correlation coefficient, which indicated an increased maturing rate by the increased number of remaining leaves. 2 : The 1.000 grain weight, grain weight and hulled rice yield increased by leaf prunning in order (plot a$A_1$, $A_3$, $A_2$ and $A_0$ were 89.8%, 89.4%, 87.8% and 87.5% respectively, showing the highest of rate in $A_1$ and $A_3$ in methods of ear fertilization and being highly significant between its treatment. 3 : 1000 grain weights were highly significant between time of application, showing a tendency of increase of weights with the time lagging until days before earings as that of maturing rates. High significance was recognized between methods of ear fertilization, showing the highest in $A_2$ 23.18 gr. 4 : Yields per $3.3m^2$ were not significant between time of ear fertilization, whereas were highly significant between methods of ear fertilization. Those of $A_1$, $A_3$, $A_2$ and $A_0$ were 1.486 kg, 1.491 kg, 1.381 kg and 1.328 kg, respectively, showing the highest in $A_1$ and $A_3$. 5 : Hulling ratios showed significant different between time of ear fertilization, showing the highest in $T_2$, whereas those of methods of ear fertilization were highly significant between its treatment, Those of $A_1$, $A_3$, $A_2$ and $A_0$ were 84.72%, 84.06%, 83.29%, and 82.56% respectively, showing the highest m $A_2$ and $A_3$ among others. 6 : Yields of hulled rice per $3.3m^2$ showed significant different between time of ear fertilization, showing the highest in $T_1$ 1.192 kg. Whereas, those were highly significant between methods of ear fertilization. Those of $A_1$, $A_3$, $A_2$ and $A_0$ were 1.259 kg, 1.254 kg, 1.149 kg and 1.095 kg, respectively, showing the highest in $A_1$ and $A_2$. 7 : Contents of nitrogen on rice plant increased in case of nitrogen application as ear fertilizer and showed that the case of urea foliar application was more effective than that of soil application, showing the increased nitrogen content of rice plant was accompanied by carbon content.

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Study on the Salt Tolerance of Rice and Other Crops in Reclaimed Soil Areas. -6. On the Effects of Increased N. P. K. Applications for Rice Plant in Reclaimed Salty Areas (간척지(干拓地)에서 수도(水稻) 및 기타작물(其他作物)의 내염성(耐鹽性)에 관(關)한 연구(硏究) -6. 염분간척지(鹽分干拓地)에서 수도(水稻)에 대한 N, P, K,의 증비효과에 관(關)하여)

  • Im, H.B.
    • Korean Journal of Soil Science and Fertilizer
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    • v.3 no.1
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    • pp.35-41
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    • 1970
  • The experiment was conducted at the salt concentration of 0.5% and 1% end of April, respectively, in low and high-salty and the non-salty areas of silt loam with the Nongkwang, rice variety. The factorial design with confounding blocks of 3 levels each of 10, 15 and 20 kg of N, 8, 12 and 16kg of phosphate and potash, respectively, per 10a was applied. 1. N applications increased by 1.5 and 2 times with the fixed amount of $P_2O_5$ and $K_2O$ (8kg/10a each) increased the proportion absorbed to the applications of N in both non salty and low-salty areas. It was observed that the absorption of Ca and Si was inhibited by either an increased treatment of N alone or combination with the other nutrients in the salty area. 2. In the non-salty area, an increased applications of standard amount of N, $P_2O_5$ and $K_2O$ respectively did not increased the yields. Doubling the application of $K_2O$ resulted in a decreased yield. 3. Applications of additional of 1.5 and 2 times the 10 kg of N per 10a increased the rice yields 12% and 21% respectively, in the low-salty area. An increased application of $P_2O_5$ and $K_2O$ failed to bring about an increased yield. 4. Increasing the application of N gave a significant increased in the yield of rice grain and 1.5 times of N applications were seemed profitable on the high-salty area. Although an increased applications $P_2O_5$ and $K_2O$ seemed to increase the yields of grain, no significant increase was observed. 5. An increased application of N increased the number of panicles up to 1.5 times the standard amount in the non-salty area, but no further increase resulted by doubling the application. The number of panicles was increased in proportion to the increased application of N in both low and high-salty areas. An increased application of $P_2O_5$ increase the number of panicles per unit area in each experimental plot while that of $K_2O$ had no effect but rather decreased the number. 6. The effect of an increased application of N decreased the weight of panicle in the non-salty area, but when the application was increased to 1.5 times or more an increased weight of panicle resulted in both salty areas. Doubling the application had approximately the same effect as 1.5 times the application. Increasing the applications of $P_2O_5$ and $K_2O$ had no effect on the panicle weight in the experimental plots. Increasing the applications of N, $P_2O_5$ and $K_2O$ did not effect the weight of 1,000 grains produced in the non-salty and salty areas. Increasing the application of N decreased the number of grains per panicle in the non-salty area but increased the number of grains per panicle in either salty areas. 7. The ratio of matured grains was highest in the low-salty area and the lowest in the high-salty area. An increased N applications decreased the ratio of matured grains in the non-salty area. No effect was observed in both low and high-salty areas. Increased the $P_2O_5$ and $K_2O$ application showed no effect on the ratio of matured grains in the experimental plots. 8. Increased applications of N, $P_2O_5$ and $K_2O$ was observed not to change the percentage of milling recovery in any experimental plots. Broken rice was increased equally by an increased application of N in the non-salty and salty areas but more remarkably so in the former. 9. Increased applications of N increased the straw production equally in the non-salty, low and high-salty areas. However, no increased production was observed from heavier applications of $P_2O_5$ and $K_2O$. Additional N applications reduced the rate of rough grain weight v.s. straw weight in the non-salty area but increased the ratios in both low and high-salty areas. Additional $P_2O_5$ and $K_2O$ had no effect with the ratio.

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A Study on the Mineral Content of Calcium-fortified Foods in Korea (우리나라의 칼슘강화식품의 무기질 함량에 관한 연구)

  • 김욱희;김을상
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.1
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    • pp.96-101
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    • 2003
  • This study was done to analyze the contents of minerals, to compare the measured values of calcium and the labeled values in food labeling and to analyze the ratio of calcium to other minerals in 43 calcium-fortified Food products sold in markets in Seoul, Korea. Content of minerals such as Ca, P, Mg, Na, K, Fe, Cu, Zn was measured by atomic absorption or colorimetric method after dry-ashing or wet-ashing. The measured values of calcium were ranged 65.5~343.9% of the labeled values in 43 calcium-fortified products. In 21 calcium-fortified food products, the measured calcium values were ranged 120~160% of the labeled values, and in three drinks those were less than 80% of the labeled, which is not acceptable to the food regulation. The ratios of Ca:P were 2.63$\pm$1.99 (mean$\pm$SD) in grain Products, 1.79$\pm$0.39 in Ramyuns, 2.80$\pm$0.53 in retort pouch food products and 8.35$\pm$12.87 in drinks. The Ca:Fe ratios were 126.33$\pm$44.36 in grain products, 130.65$\pm$34.67 in Ramyuns, 120.31$\pm$71.15 in retort pouch food products and 700.25$\pm$553.70 in drinks. The ratios of Ca:Mg were 11.86$\pm$5.40 in grain products, 9.29$\pm$1.34 in Ramyuns, 9.09$\pm$2.09 in retort pouch food products and 32.50$\pm$41.35 in drinks. The P:Mg ratios were 4.11$\pm$1.54 in grain products, 4.17$\pm$0.67 in Ramyuns, 2.58$\pm$0.45 in retort pouch food Products and 2.59$\pm$2.50 in drinks. These results suggest calcium contents and the ratio of calcium contents to other minerals in calcium-fortified food products should be strictly controlled.

Parameters on Physiological Responses of Soybean (Glycine max Merr.) to Salinity (염분에 대한 콩의 생리학적 반응지표 연구)

  • Chon, Sang-Uk;Park, Jong-Hwan
    • Korean Journal of Environmental Agriculture
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    • v.22 no.3
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    • pp.185-191
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    • 2003
  • The mechanism imparting salt tolerance to crop plants remains still unsolved, although soybean has been classified as a susceptible plant to NaCl. To determine optimum parameters on physiological responses for improving sensitivity of salinity in breeding program, soybean (Glycine max Merr., cv. "Gwan-gan") plants were grown in a greenhouse, treated 20 days after emergence for 7 days with NaCl at 0, 30, 60, and 90mM, corresponding to electric conductivity of 1.2, 4.4, 7.3, and 10.4 dS/m, respectively, and assessed 30 days after treatment. Chlorophyll contents were significantly decreased by NaCl ($0.4{\sim}1.0\;mg/g$) compared to control (1.2 mg/g). Photosynthesis rate by NaCl treatment at $0{\sim}90\;mM$ at flowering stage was ranged from 5.0 (control) to $9.6\;{\mu}mol/m^2/s$. Oxygen for respiration was consumed from 5.4 to $9.7\;{\mu}mol/m^2/s$ so that the ratio of $O_2$ (evolution:consumption) was increased with the increase of NaCl, indicating that $O_2$ consumption seems to go beyond $O_2$ evolution. Water potential of leaf at vegetative stage II was ranged from -0.6 to -1.8 MPa and the highest level was observed at mid-day. Water potential by salt stress was decreased with range of $-2.1{\sim}-2.7MPa$ compared to control. Transpiration was decreased from 17% to 20% by NaCl stress. Water vapor diffusing resistance of intercellular air space was affected significantly, increasing up to $16{\sim}24%$ compared to control by NaCl treatment. Salt-treated soybean tended to accumulate $Na^+$, specially in root, with reduced absorption of N, P, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ contents. Free proline content of soybean leaf as affected by different NaCl concentrations was increased 4.2 times ($184{\sim}434\;{\mu}g/g$) more than control. NaCl also increased activities of nitrate reductase and peroxidase by $28{\sim}161%$ and $3{\sim}22%$, respectively. The results show that physiological characteristics of soybean plants during assay were useful as the best parameters of salt stress or salt tolerance test to improve sensitivity in screening and breeding program among cultivars or germplasms.

The responses of Growth and Physiological traits of Acer triflorum on Calcium Chloride ($CaCl_2$) Concentration (염화칼슘 농도에 따른 복자기의 생장 및 생리적 반응 특성)

  • Kwon, Min-Young;Kim, Sun-Hee;Sung, Joo-Han
    • Korean Journal of Environment and Ecology
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    • v.28 no.5
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    • pp.500-509
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    • 2014
  • To prevent freezing of the road by fallen snow, Calcium chloride($CaCl_2$) as a deicer is used to very often and it can be harmful to roadside trees. This study was conducted to investigate the effects of Calcium chloride($CaCl_2$) as a deicer on growth and physiological traits of Acer triflorum according to different concentration of $CaCl_2$. We measured growth, chlorophyll contents, gas exchangement characteristics, chlorophyll fluorescence and mineral nutrition concentration in plant and soil. The experimental group was composed of four treatments including 0mM(control), 9mM(0.5 %), 18mM(1.0 %), 54mM(3.0 %). Before germinating new shoot, the dissolution of $CaCl_2$ was irrigated twice interval of a week. At 30 days after treatment, all treatments decreased total cholorophyll content, photosynthetic rate, transpiration rate, stomatal conductance and photochemical efficiency($F_v/F_m$) with increasing concentration of $CaCl_2$ and especially, they significantly reduced in 3.0 % treatment. In contrast, chlorophyll a/b ratio increased with an increase of $CaCl_2$ concentration and water use efficiency increased in 1.0 % and 3.0 % treatments. At 50 days after treatment, all treatments were decreased in chl a, chl b, total chlorophyll content, carotenoid content, photosynthetic capacity, photochemical efficiency($F_v/F_m$) and quantum yield of photosystem II(${\Phi}_{PSII}$) compared with control and 3.0 % treatments were withered. $Ca^{2+}$ and $Cl^-$ were accumulated in leaves and soil, which inhibited water absorption and electron transport and it caused the reduction of height growth rate more than 50 %. Although there was a little difference according to time and $CaCl_2$ concentration, all treatments decreased in growth rate and physiological activity slowed down. As time passed, these results got worse. Therefore we need to take a measure earlier in order to minimize damage of trees.

The Characteristics of phosphorus in major Korean soils. -I. The characteristics of inorganic phosphorus (우리나라 주요토양중(主要土壤中) 인산(燐酸)의 특성(特性)에 관(關)한 연구(硏究) -I. 무기태인산(無機態燐酸)의 분화정량치(分畵定量値)를 중심(中心)으로)

  • Hong, Jung-Kook;Hong, Chong-Woon
    • Korean Journal of Soil Science and Fertilizer
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    • v.10 no.1
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    • pp.13-22
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    • 1977
  • The following results were obtained in this work intended for getting more informations on features of phosphorus in Korean characteristic virgin, upland and paddy soils for knowing the ways how to evaluate the soil phosphorus availability and utilize fertilizers efficiently. 1. A large part of soil phosphorus is occupied by inorganic phosphorus in the soils of which the cultivated soils showed higher accumulation of applied phosphorus as inorganic forms than the uncultivated soils. The accumulation of organic phosphorus was indicated the highest in the paddy soils, and the lowest in the uncultivated soils. Than the cultuivated soil, the uncultivated soils have higher C/P ratio which was estimated to be related to soil fertility status essentially. 2. Iron phosphate was shown to be the most dominant form in soil phosphorus. Difference in parent rocks, from which the soils were originated, was shown to affect the carious distribution of phosphorus forms in the uncultivated soils to a large extent. The paddy soils have almost same distribution pattern of soil phosphorus forms regardless of different parent rocks. 3. The different methods for available phosphorus estimation extracted different amounts of phosphorus from the soils. Close relations between the available phosphours extracted with the different methods and the amounts of seil inorganic phosphorus were shown : e.g. between Fe-P and available-P by Olsen method. 4. Phosphorus absorption coefficient correlated negatively to soil inorganic phosphorus, and also to available phosphorus extracted with the several methods.

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