• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.413-420
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• 2001

To prevent salt accumulation in cut-flower rose soil through proper nutrient management, the optimum concentration of nitrogen and potassium for fertigation was investigated. For the purpose, 'Noblesse' cut-flower roses was transplanted to a sandy loam soil in a plastic house and four nutrient levels (0, 25, 50 and $100mg\;l^{-1}$) of N and K separately were applied by drip-irrigation under -20 kPa of soil moisture tension. The growth and yield responses were assessed in terms of the length, weight and number of cut-flower roses, and the nutrient availability absorbed by plant. The length of cut-flowers was not affected by N concentration, but the weight and number of cut-flowers were greatest at $50mg\;N\;l^{-1}$. For K, the length and weight of cut-flowers were greatest at 25 and $50mg\;l^{-1}$, but the number of cut-flowers were remarkably great at $50mg\;l^{-1}$. Despite of increase of N and K fertigation concentration ranged from 25 to $100mg\;l^{-1}$, there was not significant difference between the uptake concentration of plant parts. As a result, the availability of N and K in $50mg\;l^{-1}$ fertigation was highest when compared to other fertigation concentrations, while the remaining amounts of N and K to soil was very low. The results of this study suggested that N and K concentrations of $50mg\;l^{-1}$ would be adequate for the fertigation of 'Noblesse' cut-flower rose.

• Journal of Bio-Environment Control
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• v.26 no.1
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• pp.35-42
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• 2017

This research was conducted to investigate the influence of post-planting fertilizer concentrations on the growth of seedlings and changes of nutrient concentrations of media in tomato seedling production through sub-irrigation. Two root media such as peat moss (grade of 0 to 6 mm, PM06) plus perlite (grade of 1 to 2 mm (PE2)(7:3, v/v) and peat moss (grade of 5 to 15 mm, PM515) plus PE2 (7:3, v/v) were formulated and filled into 72-cell plug trays. After seeds of 'Dotaerang Dia' tomato were sown and germinated at $28^{\circ}C$, the trays were moved to greenhouse and seedlings were raised 35 days. When the cotyledons were emerged, post-planting fertilizers of 13-2-13, 15-0-15 and 20-9-20 ($N-P_2O_5-K_2O$) were applied in a sequence. The fertilizer concentrations based on N in each plug stage were differed with $25mg{\cdot}L^{-1}$ in three treatments. The fertilizer solutions were supplied when the weight of plug trays decreased to 40 to 50% compared to container capacity. The root media were collected in 1, 2, 4, and 5 weeks after sowing and were divided into top, middle, and bottom parts, then were analysed for pH, EC and macro-nutrient concentrations. The seedling growth was investigated 5 weeks after sowing. The pH and EC in PM06+PE2 was higher than those of PM515+PE2. The bottom and mid-part had higher pH and lower EC compared to upper part in each medium. The differences of EC between upper and bottom parts were around 2 times in each medium. The $NH_4-N$ and K concentrations in program 3 of PM06+PE2 showed the highest concentrations among all treatments. The $NO_3-N$ concentrations in PM06+PE2 increased gradually and this rising tendency become severe as post-planting fertilizer concentrations were elevated. The seedling growth in terms of fresh and dry weights was the highest in the treatment of program 2 in PM06+PE2 among all treatments tested. Above results indicate that the gradual increases of fertilizer concentrations from 25 to $125mg{\cdot}L^{-1}$ in plug stages 2, 3, and 4 plug stages are desirable for

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.554-563
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• 2013

The purpose of this study is to evaluate the possibility of nutrient release at up and downstream of Kangchun weir, upstream of Yuju and Ipo weir in Namhan River. For this survey, we measured basic characteristics of the sediments (water content, ignition loss, TOC, TP, SRP, TN, phosphorus fractionation) and conducted nutrients release experiments under both aerobic and anaerobic condition. The overlying water from the sediment-water column was analyzed for nutrients (i.e. TP, $PO_4$-P, TN, $NO_3$-N, $NH_3$-N) everyday for 18days. Result of soil texture experiment showed that sediments are Sand. SRP concentration before the release experiment was different with the value after the release experiment. According to this result, we can find that there were more activated release processes in anaerobic condition. $PO_4$-P increased from 1 to 8 days and remained at the maximum value (7~8 days) afterward. The rapidly increase of $PO_4$-P was observed from 1 to 2~3 days whereas the TP continuously increase from 1 to 18 days. The $PO_4$-P release rate calculated by up to 7~8 days data highly correlated with initial SRP concentration with $R^2$=0.8502. $NO_3$-N release rate appears constantly decreasing trend as -5.7~-3.08 $mg/m^2{\cdot}day$, otherwise the $NH_3$-N release rate, by-product of a organic matter decomposition using nitrate as electron acceptor, was 0.57~2.41 $mg/m^2{\cdot}day$. Substantial portion in TN can be induced by organic nitrogen which originated from the tributary passing through non-point pollutant source. Compared with other similar researches, phosphorus and nitrogen release rates obtained in this study can be considered as relatively low values. Since this study targeted the sediments accumulated by one time of flooding season, there are limitation to generalize theses results. Therefore, it is necessary to consistently monitor and investigate the accumulation of nutrients in the sediment for understanding the effect of weir construction on the overlying water quality.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.198-209
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• 2021

This study evaluated the effects of the dimensional characteristics of containers on the nitrogen status of Quercus serrata, Fraxinus rhynchophylla, and Zelkova serrata in the container nursery stage. Seedlings were grown using 16 container types [four growing densities (100, 144, 196, and 256 seedlings/m²) × four cavity volumes (220, 300, 380, and 460 cm³/cavity)]. Two-way ANOVA was performed to test the differences in nitrogen concentration and seedling content among container types. Additionally, we performed multiple regression analyses to correlate container dimensions and nitrogen content. Container types had a strong influence on nitrogen concentration and the content of the seedling species, with a significant interaction effect between growing density and cavity volume. Cavity volumes were positively correlated with the nitrogen content of the three seedling species, whereas growing density negatively affected those of F. rhynchophylla. Further, nutrient vector analysis revealed that the seedling nutrient loading capacities of the three species, such as efficiency and accumulation, were altered because of the different fertilization effects by container types. The optimal ranges of container dimension by each tree species, obtained multiple regression analysis with nitrogen content, were found to be approximately 180-210 seedlings/m² and 410-460 cm³/cavity for Q. serrata, 100-120 seedlings/m² and 350-420 cm³/cavity for F. rhynchophylla, and 190-220 seedlings/m² and 380-430 cm³/cavity for Z. serrata. This study suggests that an adequate type of container will improve seedling quality with higher nutrient loading capacity production in nursery stages and increase seedling growth in plantation stages.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.97-106
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• 2024

Evaluating carbon (C) and nitrogen (N) inputs from litterfall is important for soil nutrient management to enhance forest productivity and to understand the mechanisms of nutrient cycling in forest ecosystems. This study was conducted to compare C and N inputs from litterfall components of Cryptomeria japonica D. Don an d Chamaecyparis obtusa Endlicher planted in adjacent sites in the Jinju Research and Experimental Forests in Gyeongsangnam-do, South Korea. Litterfall into litter traps was collected at three-month intervals between December 2020 and December 2021, and the C and N concentrations of the litterfall components were measured. Litterfall amounts were not significantly different between the plantations, except for reproductive litterfall components. Litterfall accumulation peaked between December and March. The litterfall C concentration in the needle and seed litterfall was significantly higher for C. obtusa than for C. japonica. By contrast, the C concentrations in needle and flower litterfall differed seasonally. The mean N concentration of needle litterfall was significantly higher in C. japonica (0.96%) and C. obtusa collected between June and September (1.01%) than in the other seasons (C. japonica: 0.43%; C. obtusa: 0.53%). Carbon and N inputs in both plantations were highest in needle litterfall collected from December to March and lowest in needle litterfall collected from June to September. Annual C input by litterfall was similar between the plantations (C. japonica: 3,054 kg C ha^-1 yr^-1; C. obtusa: 3,129 kg C ha^-1 yr^-1), whereas total N input was higher for C. japonica (46.93 kg N ha^-1 yr^-1) than for C. obtusa (25.17 kg N ha^-1 yr^-1). The higher N input in the C. japonica plantation than in the C. obtusa plantation was associated with the input of reproductive components. These results could be applied to improve stand-scale models of C and N cycling by litterfall components in C. japonica an d C. obtusa plantations.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.665-672
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• 2013

This study was conducted to evaluate the effects of a chelating agent on cucumber growth and changes in soil nutrients availability in polytunnel greenhouse fields. Diethylene triamine penta acetic acid (DTPA) was selected as a chelating agent. Two experiments were carried out as follows: i) For field experiment in the autumn season of 2010, each plot was treated by varying the concentration and the number of times being applied with DTPA; [DTPA (0.5 mM, 1 time/3 months), DTPA (0.06 mM, 1 time/1 week), DTPA (0.13 mM, 1 time/2 weeks), DTPA (0.06 mM, 1 time/1 week)+N]. Conventional practice was also investigated. ii) In the spring and summer seasons of 2011, each plot was treated by varying the concentration (0, 0.06, 0.13, 0.19 mM) of DTPA, chemical fertilizers (NPK), and combination of chemical fertilizers and DTPA 0.06 mM. The fruit yields of cucumber and soil chemical properties had no significant differences between treatments. However, in the spring season of 2011, DTPA 0.06 mM plot added 1 time per 2 weeks increased the yield of cucumber, but caused the reduction of yield in next cultivation season. This result showed that excess use of DTPA can cause the damage of crop growth. The inorgainc contents such as Ca and Mg absorbed by cucumber plant had significant differences between DTPA 0.19 mM (2 times/1 week) and fertilizers plus DTPA treatments [DTPA 0.06 mM (2 times/1 week) + 1/2 NPK, DTPA 0.06 mM (2 times/1 week) + NPK]. The input cost of fertilizers was saved when the concentration and the number of times added with DTPA was 0.06 mM and 1 time a week, respectively. This treatment used 67% less of applied fertilizers cost than the plot of conventional practice did. Thus, this research suggested that the application of DTPA 0.06 mM by 1 time a week can be effective for sustainability of crop production and reduction of fertilizers usage in polytunnel greenhouse.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1279-1287
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• 2009

Concentrated livestock production has led to soil nutrient accumulation concerns. To reduce the environmental impact, it is necessary to understand current recommended livestock feeding practices. Two experiments were conducted to compare the effects of trace mineral supplementation on performance, carcass composition, and fecal mineral excretion of phase-fed, grow-finish pigs. Crossbred pigs (Experiment 1 (Exp. 1), (n = 528); Experiment 2 (Exp. 2), (n = 560)) were housed in totally-slatted, confinement barns, blocked by weight, penned by sex, and randomly assigned to pens at approximately 18 kg BW. Treatments were allocated in a randomized complete block design (12 replicate pens per treatment) with 9 to 12 pigs per pen throughout the grow-finish period. In Exp. 1, the control diet (Io100) contained Cu as $CuSO_{4}$, Fe as $FeSO_{4}$, and Zn (of which 25% was ZnO and 75% was $ZnO_{4}$) at concentrations of 63 and 378 mg/kg, respectively. Treatment 2 (O100) contained supplemental Cu, Fe, and Zn from organic sources (Bioplex, Alltech Inc., Nicholasville, KY) at concentrations of 19, 131, and 91 mg/kg, respectively, which are the commercially recommended dietary inclusion levels for these organic trace minerals. Organic Cu, Fe, and Zn concentrations from O100 were reduced by 25% and 50% to form treatments 3 (O75) and 4 (O50-1), respectively. In Exp. 2, treatment 5 (Io25) contained 25% of the Cu, Fe, and Zn (inorganic sources) concentrations found in Io100. Treatment 6 (O50-2) was identical to the O50-1 diet from Exp. 1. Treatment 7 (O25) contained the experimental microminerals reduced by 75% from concentrations found in O100. Treatment 8 (O0) contained no trace mineral supplementation and served as a negative control for Exp. 2. In Exp. 1, tenth-rib backfat, loin muscle area and ADG did not differ (p>0.05) between treatments. Pigs fed the control diet (Io100) consumed less feed (p<0.01) compared to pigs fed diets containing organic trace minerals, thus, G:F was greater (p = 0.03). In Exp. 2, there were no differences among treatment means for loin muscle area, but pigs fed the reduced organic trace mineral diets consumed less (p<0.05) feed and tended (p = 0.10) to have less tenth-rib backfat compared to pigs fed the reduced inorganic trace mineral diet. Considering that performance and feed intake of pigs was not affected by lower dietary trace mineral inclusion, mineral excretion could be reduced during the grow-finish phase by reducing dietary trace mineral concentration.

• Korean Journal of Community Nutrition
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• v.15 no.1
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• pp.137-148
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• 2010

This study was conducted on 175 child-care teachers, who participated in in-service education, to research the methods to improve child-care teacher's nutrition management capability for infants and children. Investigated results of child-care teachers' nutrition knowledge, dietary attitude status, and needs on nutrition education in child-care centers are as follows: The score of child-care teachers' nutrition knowledge was 10.83 points out of 15, which is about 72%. Total score increased as teachers' age but not significantly different from their career duration, since teachers who have a child-care career less than 5 years acquired 10.91 points, which is higher than 10.64 points of teachers having more than 5 years of child-care career. Teachers' average recognition to the nutrition knowledge was 90.6%, increased significantly by the older they are, and decreased according to the accumulation of their career. The average accuracy of the nutrition knowledge was 79.7%, increased in proportion to the teachers' age. The marks of child-care teachers' dietary attitude were 41.3 points (possible score range 5-50) and 83%, older teachers tended to have more desirable dietary attitude. As indicated by the increment of child-care career, the score of emotional attitude tended to be increased but which of cognitive and behavioral attitude showed a declining tendency. Nutrition information which child-care teachers were mainly interested in were correct selection of food (58.1%), obesity and weight management (52.7%), and nutrient content of food (44.9%). Nutrition education contents which child-care teachers needed were 'nutritious food and menu for child' (72.2%), 'health management of child' (69.2%) and meal management of child (40.2%). Nutrition education methods, which child-care teachers considered as of desirable ones, were cooking class of small scale (31.8%), visiting class at child-care center (26.5%). In consequence, the nutrition knowledge and dietary attitude of child-care teachers were not good and showed different issues by age and career duration. Therefore, it is requisite to intensify nutrition management courses in child-care teachers' qualification and in-service education courses which has actual necessity and suitability based on teachers' age, career, and the type of child-care center, and to disseminate these through public health centers and child-care & education information centers to pursue the efficient balance of nutrition education programs.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.262-270
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• 2014

BACKGROUND: Coal combustion bottom ash(BA) has high carbon and calcium content, and alkaline pH, which might improve nutrient cycling in soil related to microbial enzyme activities as it is used as soil amendment. However, it contains heavy metals such as copper(Cu), manganese (Mn), and zinc(Zn), which could cause heavy metals accumulation in soil. Compost might play a role that stabilize BA. The objective of this study was to evaluate effect of combined application of BA and compost as soil amendment on heavy metals concentration, enzyme activities, chemical properties, and crop yield in upland soil. METHODS AND RESULTS: BA was applied at the rate of 0, 20, 40, and 80 Mg/ha under different rate of compost application (0 and 30 Mg/ha) in radish (Raphanus sativus var) field. Combined application of BA and compost more improved chemical properties such as pH, EC, OM, total nitrogen, available phosphate, and exchangeable cations of soil than single application of BA. Water soluble Mn and Zn concentration in soil significantly decreased with increasing application rate of BA. Decrease in those metals concentration was accelerated with combined application of BA and compost. Urease and dehydrogenase activities significantly increased with increasing application rate of BA. Phosphotase activities were not affected with single application of BA but increased with combined application of BA and compost. Radish yield was not affected by application rate of BA. CONCLUSION: From the above results, combined application of BA and compost could be used as soil amendment to improve chemical properties and enzyme activities of soil without increase in heavy metal concentration and decrease in crop yield in upland soil.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.131-137
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• 1996

This analysis has been conducted to get some basic data of the composition of culture solution mostly in inorganic ions, and water quality in hydroponic farms in Chollabuk - do. pH range was shown from 6.00 to 7.65 and the average was 6.58. EC range was shown from 0.01 to 0.94 mS/cm and the average was 0.28 mS/cm. Na concentration ranged from 4.71 to 145.44 ppm and Cl concentration ranged from 0 to 171.80 ppm were shown and their average were 24.24 ppm and 26.33 ppm, respectively. Na and Cl concentrations were higher as 7.7%, compared to those of other farms, which could cause the salt accumulation in the substrate mats. K, Ca and Mg concentrations were ranged from 0.93 to 17.38 ppm, 2.29 to 34.30 ppm and 0.70 to 18.61 ppm, respectively. Average concentrations were 3.06 ppm in K, 13.00 ppm in Ca and 4.91 ppm in Mg. 50, and PO$_4$ concentration ranged from 0.63 to 59.79 ppm and 0 to 4.28 ppm were shown and their average were 18.11 and 0.51 ppm. Cu concentration was ranged from 0 to 0.32 ppm and 0 to 6.22 ppm in Zn concentration. Their average were 0.02 ppm and 0.52ppm, respectively.