• The Korean Journal of Ecology
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• v.7 no.3
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• pp.170-176
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• 1983

The results obtained from the experiments conducted to investigate Cruciferae plants in rape dependent on the amount of applied fertilizer in aspects of mineral nutrient uptake and on the effects of the composition of oil quality are as follows: Absorption of mineral nutrients in the respective pars of the plant body was high in nitorgen in the order of leaf and stem

• Journal of the Korean Institute of Navigation
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• v.11 no.1
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• pp.1-38
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• 1987

The amount of cargoes by cargo vessels has increased tremendously during the last decade due to the great growth of korea economy. But in spite of this trend, there is rarely the substantial analyzed on the operational status of coastal shipping. In this paper, the characteristics of seaborne cargo and traffic flow of coastal shipping surveyed in detail through the statistical and the origintain and destination (O.D) analysis. Also, the basic ship's tonnage of coastal shipping representing the minimum tonnage which is capable of carrying the given seaborne cargo is suggested through the computer simulation using the data of 1985 year. The results are as follows; 1) the about 80% of total coastal traffic volume is going in/out to the port of Incheon, Busan, Pohang, Samil, Bukpyung, Mukho, Samchuk, and Jeju. 2) The main cargo items such as oil, iron material, cement, anthracite grain, fertilizer, other ore are reached to the about 70% of total amount of coastal trade. 3) ship's tonnage going in/out to the port of Bukpyiung, Busan, Pohang is increasing linearly year by year, and the amount of oil, iron material, cement, anthracite, grain, fertilizer, other ore are also increasing in linear pattern. 4) As a result of simulation, the optimum (basic) ship's tonnage.

• Korean Journal of Organic Agriculture
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• v.9 no.3
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• pp.103-117
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• 2001

This study was inducted to investigate the effects of microbial fertilizers on the fields of young radish(Raphanus sativus L.), chemical components of plant and soil, and the microbial floras. Six microbial fertilizers, MPK+Husk+Palma, Husk+Palma, MPK+Compost, Compost, BIO Livestock Clean System(BLCS) cattle dropping, and Tomi were used. The yields of young radish were increased in six microbial fertilizer treatments. The fresh matter weight, the number of leaves, and the dry matter weight of young radish in BLCS cattle dropping treatment, the leaf length in MPK+Husk+Palma treatment, the sugar content in Husk+Palma treatment, arid the leaf width in Tomi treatment showed the highest amount, respectively. The effects of microbial fertilizers on chemical characteristics of young radish and soil were examined. Phosphoric acid amount of young radish in Tomi treatment was much higher than other treatments. Potassium amount of young radish showed high significance in all microbial fertilizer treatments compared with control, and shoved the highest in Compost treatment . Two components, phosphoric acid find potassium, in soil inoculated by microbial fertilizers showed significant. Phosphoric acid in the Tomi treatment and Potassium in Husk+Palma treatment were increased. The microorganic populations in soil inoculated with microbial fertilizers were examined. While the number of Bacillus in ceil was increased in MPK+Husk+Palma treatment, the numbers of total bacteria, actinomycetes, and fungi were increased in Tomi treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.166-170
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• 1992

An experiment was conducted to study the dffects of fertilizers on maize tillering. Hybrids used were non-tillering hybrid, Nangano No.1, one of the leading hybrids in Japan and tillering hybrids, IK$_1$ /IRI develored at the Dept. of Agronomy, College of Agriculture, Chungnam National Univ., Taejon, Korea. The experiment was conducted at Dottori Prefecture in Japan. Four fertilizer levels, i. e., standard level, half amount of standard level, standard level plus composts and standard level plus two times of composts currently recommended for farmers were used. Higher fertilizer levels were effective for increasing plant weight of both hybrids. All fresh weight as well dry weight of the whole plants and plant parts of IK$_1$/IRI were higher than those of Nangano No. 1, regardless of fertilizers applied mainly due to the tiller development. The number of tillers per plant of IK$_1$/IRI was increased as the level of fertilizer was increased. Especially in sandy soil, composts seemed to be very effective in increasing tiller number per plant of IK$_1$/IRI.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.327-334
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• 2016

In order to compare phosphorus (P) behavior of livestock manure compost (LMC) and chemical fertilizer (CF) applied to the sea-reclaimed land soils, incubation experiments were conducted for five weeks. Four soils differing textural classes, sandy loam and clay loam, and electric conductivity (EC) value, high and low, were applied with CF and LMC. LMC was applied at the level of 0, 1, 2, and 3% on the soil weight basis and CF was applied at the same levels of P as LMC. The results showed that increase of P application rate of CF and LMC led to linearly increase available $P_2O_5$ and $0.01M\;CaCl_2$ extractable P contents regardless of soil texture and EC. However, 0.01M $CaCl_2$ extractable P from soil applied with CF was significantly higher than with LMC. Correlation analysis between $0.01M-CaCl_2$ extractable P and fractionated P by different extraction methods showed that $0.01M-CaCl_2$ extractable P positively correlated with KCl-P (soluble and exchangeable P) and HCl-P (Ca and Mg bound P). However, NaOH-P (Fe and Al bound P and organic P) and residual P was adverse. The amount of NaOH-P significantly influenced to the amount of 0.01M $CaCl_2$ extractable P of CF and LMC in the soils. The application of LMC at sandy loam soil could be carried out in the consideration of nutrient leaching and crop uptake.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.505-512
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• 2006

In Korea, silicate fertilization (SF) is being practiced every four years to enhance rice production. However, the relationship between nitrogen (N) and SF in view of growth characteristics and grain yield of rice has not been examined after watermelon cropping in plastic film house. This study was carried out to identify useful critical N and Si fertilizer levels to sustain grain yield and to improve N use efficiency for rice. The watermelon-rice cropping system has maintained for three seasons in each year from 1998 to 2001 by farmer before this experiment. Experiments on N and Si fertilization levels were evaluated with Hwayoungbyeo (Oryza sativa L.) in 2002 and 2003 at Uiryeong, Korea. The goal of this experiment was to find out the optimum N and Si levels to sustain rice yield by reducing excessive N fertilizer in watermelon-rice cropping system. Nitrogen fertilization (NF) levels were three ($0,\;57,\;114kg\;ha^{-1};0,\;50,\;100%$ of conventional NF amount) and five (0, 25, 50, 75, 100%) in 2002 and 2003, respectively, and combined with three SF levels ($70,\;130,\;180mg\;kg^{-1};100,\;150,\;200%$ which were adjusted with Si fertilizer in soil) were evaluated for the improvement of N and Si fertilization level in both years. Rice yielded 3.98-5.95 and 2.84-4.02 t/ha in 2002 and 2003, respectively. Our results showed the combinations of 50% and 100% of N with 200% level of Si produced the highest grain yield in both years, respectably. The grain yield was greatly improved in plot of N25% level when compared to conventional NF (Nl00%) in 2003. In conclusion, NF amount could be reduced about 50% compared to recommended level by specific fertilization of N and Si combination levels for rice growing and grain yield after cultivation watermelon in paddy field.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.1
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• pp.1-4
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• 1974

The application of the Distribution Law to soil-pesticide systems yielded the following empirical implications : 1) The amount of the pesticide adsorbed by a soil is negatively proportional to the soil water content. 2) At a given soil water content the amount adsorbed is proportional to the Kd of the soil. 3) The effect of soil water content on the amount of the pesticide adsorbed diminishes with increasing magnitude of the Kd.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.378-386
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• 1992

This experiment was conducted to investigate the effects of inoculation of the Bradyrhizobium sp.(Arachis) HCR-46 and fertilizer nitrogen application on nodulation, $N_2$-fixation of cowpea group legume(Seowon dongbu, Seonwha nogdu, Chungju pat, Youngho tangkong). Treatments consisted of five uninoc.+N : O, uninoc.+N : 6kg/10a. inoc.+N : O, inoc.+ N : 6kg/10a, inoc.+N : 12kg/10a. 1. Initial nodulation time of cowpea group legume by inoculation of Bradyrhizobium sp. HCR-46 was 12~21 days, and it was delayed as more fertilizer nitrogen was added. 2. The number and dry weight of nodule were increased as growth period elapsed, but decreased as fertilizer nitrogen was added. 3. Dry matter production and amount of nitrogen uptake were increased by inoculation and the effects of inoculation were increased when fertilizer nitrogen of 6kg/10a was applied. 4. Amount of fixed nitrogen by inoculation of fertilizer nitrogen not applied was higher than the case of 6kg/10a applied and that of peanut was higher than the other legumes(cowpea, mung bean and adzuki).

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.5
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• pp.598-607
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• 2016

This study was conducted to evaluate the amount of nitrogen (N) top dressing based on the normalized difference vegetation indices (NDVI) by ground based sensors for leaf perilla under the polyethylene house. Experimental design was the randomized complete block design for five N fertilization levels and conventional fertilization with 3 and 4 replications in Gumsan-gun and Milyang-si field, respectively. Dry weight (DW), concentration of N, and amount of N uptake by leaf perilla as well as NDVIs from sensors were measured monthly. Difference of growth characteristics among treatments in Gumsan field was wider than Milyang. SPAD-502 chlorophyll meter reading explained 43.4% of the variability in N content of leaves in Gumsan field at $150^{th}$ day after seedling (DAS) and 45.9% in Milyang at $239^{th}$ DAS. Indexes of red sensor (RNDVI) and amber sensor (ANDVI) at $172^{th}$ day after seedling (DAS) in Gumsan explained 50% and 57% of the variability in N content of leaves. RNDVI and ANDVI at $31^{th}$ DAS in Milyang explained 60% and 65% of the variability in DW of leaves. Based on the relationship between ANDVI and N application rate, ANDVI at $172^{th}$ DAS in Gumsan explained 57% of the variability in N application rate but non significant relationship in Milyang field. Average sufficiency index (SI) calculated from ratio of each measurement index per maximum index of ANDVI at $172^{th}$ DAS in Gumsan explained 73% of the variability in N application rate. Although the relationship between NDVIs and growth characteristics was various upon growing season, SI by NDVIs of ground based remote sensors at top dressing season was thought to be useful index for recommendation of N top dressing rate of leaf perilla.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.29-36
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• 1996

This experiment was conducted to investigate the effects of the application of complete fertilizer on the yields and quality of leaf tobaccod grown in soils with different fertility levels. The contents of inorganic nitrogen, organic matter and available phosphorus in the soil with high fertility level were shown to be more than those in the soils with medium and low fertility levels of the experimental fields. The contents of total nitrogen, nicotine and reducing sugar in the tobacco leaf were more than those in the cutters tobacco. The contents of total nitrogen and nicotine in the leaf tobacco increased as the application amounts of the fertilizer(10:10:20) increased, however, the reducing sugar contents in the leaf tobacco decreased. The increase in the yields of leaf tobacco was detected at the application amount of 75kg/10a in soils with high fertility level, but for high yield of leaf tobacco in the soils with low and medium levels the application amount of the fertilizer was found to be over 100kg per 10a. The quality (price/kg or price/kg ${\times}$ yield) of the leaf tobacco was known to be excellent at 50~75kg/10a of the application amount of the fertilizer(10:10:20) in soil with high fertility level and over 100kg/10a in the other soils in the experiment.