• Korean Journal of Soil Science and Fertilizer
• /
• v.15 no.4
• /
• pp.251-257
• /
• 1982

Fatty acid and sterol composition of soybean seedlings was investigated by treatment of light irradiation time. The results obtained were as follows; 1. In hypocotyl of seedlings, the proportion of linoleic and linolenic acid was in creased with increasing light irradiation time, while those of palmitic and stearic acid was decreased. 2. In root of seedlings, the proportion of palmitic and linolenic acid was decreased with increasing light irradiation time, but those of stearic and oleic acid was in creased 2 days after germination. 3. Throughout their growth, the main sterol of cotyledon was the stigmasterol but that of in hypocotyl and roots was sitosterol. 4. On 6 days after planting, the content of sitosterol was the highest in hypocotyl of seedlings recieved 24-hour irradiation. 5. The proportion of sitosterol in root was decreased with growth duration under the dark and 24 hour-irradiation condition while increased under 16 hour irradiation.

• Korean Journal of Soil Science and Fertilizer
• /
• v.24 no.3
• /
• pp.219-224
• /
• 1991

An acid tolerant R. meliloti "YA03" which was characterized through both acidified tube and pot soil experiment, was examined on its inoculation effect to alfalfa[Medicago sativa (L.)]cv. Vernal on hilly acid soil. It was conducted for 2 years to evaluate inoculation residual effect and there were two-fertilizer factors of nitrogen(0.8kg/10a) and lime(0,162kg/10a)as urea and $Ca(OH)_2$, respectively. The results obtained were summarized as follows : 1. In the 1st-year experiment, YA03 inoculated without nitrogen and lime application showed higher symbiotic effectiveness than check strains, YA026 and Rm2011 in nodule mass, $N_2$-fixing activity, and dry matter yield, but with N 8kg/10a application lower effectiveness than Rm2011. 2. In the 2nd-year experiment, Alfalfa dry matter yield by YA03 inoculation with N application(without lime) was 74% higher than that(276 kg/10a) in the 1st year, and the value showed 166%, 20%, and 21% increments as compared with noninoculated control(180kg/10a). YA026(399kg/10a), and Rm2011(397kg/10a), respectively. 3. In the 2nd-year experiment of N applicated plote(without lime), especially, YA03 showed higher shoot nitrogen(7.7kg N/10a/Yr.) fixed and soil rhizobial population($1{\times}10^4\;cells/g.\;soil$) than check strains. 4. On the basis of lime application, application effect of three major fertilizers with YA03 inoculation on alfalfa yield and soil rhizobial population was in the order of $N+P_2O_5+K_2O>P_2O_5+K_2O>P_2O_5+K_2O$. 5. On the whole, alfalfa yield by acid tolerant R. meliloti YA03 inoculation on hilly acid soil was enhanced with nitrogen application, and besides it appeared 44% higher with lime than without lime.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.5
• /
• pp.385-392
• /
• 2009

This study was conducted to reclassify Namweon series, black volcanic ash soils, in Jeju Island based on the second edition of Soil Taxonomy : A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Morphological properties of typifying pedon of Namweon series were investigated and physicochemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Namweon series has black (10YR 2/1) silt loam Ap horizon (0~11 cm) and black (10YR 2/1) silt loam BA horizon (11~72 cm). Bw horizon (72~100 cm) is very dark brown (10YR 2/2) silt loam. That occurs on lava plain derived from volcanic ash materials. The typifying pedon contains 5.2~6.4% oxalate extractable (Al + 1/2 Fe), over 85% phosphate retention, and lower bulk density than $0.90Mg\;m^{-3}$. Ap, BA, and Bw horizons of the pedon have andic soil properties. That can be classified as Andisol. The typifying pedon has an udic soil moisture regime and has a 1,500 kPa water retention of 15% or more on air-dried samples throughout all horizons, and can be classified as Udand. Ap and BA horizons (0~72 cm) have a color value, moist, and chroma of 2 or less, melanic index of 1.70 or less, and 6% or more organic carbon. That meets the requirements of melanic epipedon. That keys out as Melanudand. That has more than 6.0% organic carbon and the colors of mollic epipedon throughout a layer 50 cm or more thick within 60 cm of the mineral soil surface.. Thus, that keys out as Pachic Melanudand. The pedon has a fine-earth fraction that has a water content at 1,500 kPa tension of 12% or more on air-dried samples and has less than 35% (by volume) rock fragments. Thus, the substitute for particle-size class is medial. That has a sum of 8 times the Si (percnt by weight extracted by acid oxalate) plus 2 times the Fe (percnt by weight extracted by acid oxalate) of 5 or more, and 2 times the Fe is more than 8 times the Si. Thus, the mineralogy class is ferrihydritic. Namweon series can be classified as medial, ferrihydritic, thermic family of Pachic Melanudands, not as ashy, thermic family of Typic Melanudands.

• Journal of Radiation Protection and Research
• /
• v.37 no.4
• /
• pp.213-218
• /
• 2012

Alpha spectrometry has been typically used for determination of the uranium isotopes in soil. For a number of uranium analysis in soil samples, rapid sample digestion with limited quantities of mixed acid containing HF will give a contribution for effective management of uranium analysis. Microwave digestion system is evaluated for rapid sample digestion using reference uranium soil (IAEA-375 soil). For completion of 0.5 g of soil digestion by microwave, 3 ml of HF in a 10 ml of mixed acid is minimum requirement volume for completed soil digestion for 80 minutes. Microwave digestion is timely effective techniques for uranium measurement using alpha spectrometry compared to the other methods (open vessel digestion, closed vessel digestion) due to rapid sample digestion. In addition, it can be reduced the occurrence of hazardous substances by minimizing the amount of HF.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.15 no.1
• /
• pp.1-12
• /
• 1995

This study was to investigate an effective biological control of forage diseases and provide a basic data and a model in improving variety of antagonistic bacteria, with growth promoting effect on forage, through cell fusion. The results obtained were summarized as follows; 1. The antagonistic himbacterium against soil-borne phathogenic fungi Fusarium oxysporum and Rhizoctonia solani was isolated from continuous cropping himsphere soil of forage, and its biological and physiological characteristics were investigated. This bacterium was identified as Bacillus subrilis and named BS 101. Another strain for cell fusion was Bacillus thur ingiensis ssp. kurstaki HD-I(BT 37669) with insecticidal crystal. 2. The auxotropic mutants of BS 101 and BT 37669 were derived after mutagenesis using N-methyl-N'nitro- Nitrosoguanidine(NTG) to give amino acid requirement marker. n e s e auxotropic mutants of BS 101 and BT 37669 were named BS 1013(his-) and BT 69(asp-), respectively. 3. The best protoplast requirement was obtained using DM 3 medium, containing 5% casamino acid, 1 M $MgCI_2$ and 2% bovine semm albumin, to give Fusant 3, 7 and 8. BT toxin gene was not identified with fusants by Southern blotting. However, SDS-PAGE analysis of strains showed various protein patterns among fusants. 4. From the dark culture experiment, growth of forage in inoculated soil with antagonistic bacteria was delayed than that of non-inoculated soil with antagonistic bacteria in each continuous cropping soil and in each sterilized soil. On the other hand, growth duration of forage was different between continuous cropping soil and sterilized soil. 5. Seed germination of Alfalfa, Italian ryegrass and Orchardgrass were significantly improved by inoculation of antagonistic bacteria(p< 0.05).

• Korean Journal of Soil Science and Fertilizer
• /
• v.49 no.6
• /
• pp.783-788
• /
• 2016

Agricultural management of paddy soil depends on the effects of soil microbial activities. The present study evaluated the soil microbial community of 25 paddy soils in Gyeongnam Province by fatty acid methyl ester (FAME). The average of microbial communities in paddy soils were 32.2% of total bacteria, 16.7% of Gram-negative bacteria, 12.9% of Gram-positive bacteria, 2.0% of actinomycetes, 14.9% of fungi, and 1.3% of arbuscular mycorrhizal fungi. The communities of total bacteria (34.9%) and Gram-negative bacteria (19.4%) in soils with $30{\sim}35g\;kg^{-1}$ of organic matter were significantly larger than those in soils with other organic matter levels. However, soils with $20{\sim}30g\;kg^{-1}$ of organic matter had significantly low ratio of cy17:0 to $16:1{\omega}7c$ and cy19:0 to $18:1{\omega}7c$ as compared with soils with $30{\sim}35g\;kg^{-1}$ of organic matter, indicating microbial stress decreased (p < 0.05). In principal component analyses of soil microbial communities, Gram-negative bacteria should be considered as a potential responsible factor for the obvious microbial community differentiation that was observed between the two different organic matter levels in paddy fields. Thus, soils containing $20{\sim}30g\;kg^{-1}$ of organic matter were responsible for strong effect on microbial biomass and stress in paddy fields.

• Journal of Soil and Groundwater Environment
• /
• v.15 no.6
• /
• pp.29-36
• /
• 2010

Several mines including Namil, Solim and Jungbong which are located in the Gyeonggi and Kangwon province have been abandoned and closed since 1980 due to "The promotion policy of mining industry". An enormous amount of mining wastes was disposed without proper treatment, which caused soil pollution in tailing dam and ore-dressing plant areas. However, any quantitative assessment was not performed about soil and water pollution by transporting mining wastes such as acid mine drainage, mine tailing, and rocky waste. In this research, heavy metals in mining wastes were analyzed according to leaching method which used 0.1 N HCl and total solution method which used Aqua-regia to recognize the ecological effect of distance from hot spot. We sampled tailings, rocky wastes and soils around the abandoned mine. Chemical and physical parameters such as pH, electrical conductivity (EC), total organic carbon (TOC), soil texture and heavy metal concentration were analyzed. The range of soil's pH is between 4.3 and 6.4 in the tailing dam and oredressing plant area due to mining activity. Total concentrations of As, Cu, and Pb in soil near ore dressing plant area are 250.9, 249.3 and 117.2 mg/kg respectively, which are higher than any other ones near tailing dam area. Arsenic concentration in tailing dams is 31.0 mg/kg, which is also considered as heavily polluted condition comparing with the remediation required level(RRL) in "Soil environment conservation Act".

• Korean Journal of Soil Science and Fertilizer
• /
• v.48 no.1
• /
• pp.64-71
• /
• 2015

Soil contamination with arsenic and heavy metals is a worldwide problem. Main objective of this research was to evaluated effects of reducing heavy metal leaching under reduced soil condition amended with industrial by-products. The contaminated soil was amended with 3% (w/w) of limestone (Ls), steel slag (SS) and acid mine drainage sludge (AMDS). Synthetic acid rain ($H_2SO_4:HNO_3=6:4$, pH 5.5 fixed) was used for feeding solution with flow rate of $0.78{\sim}0.88mL\;min^{-1}$. Results showed that similar pH and EC of leachate was observed in all treatments regardless of applied industrial by-products. However, arsenic concentration of leachate increased when industrial by-products were mixed. Meanwhile, concentration of heavy metal in the leachate decreased from 11.3 to 4.59 mg for Cd, from 92.3 to 7.93 mg for Pb, and from 11,716 to 1,788 mg for Zn via immobilization in soil with AMDS amended, respectively. Overall, application of industrial by-products can be an environmentally-friendly way to remediate soil and(or) leachate contaminated with metal(loid)s in metal mine site.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.6
• /
• pp.556-562
• /
• 2013

The blueberry eco-friendly farming requires the soil condition of pH 4.2 ~ 5.2 and high in organic matters for stable growth. Most of soil types of blueberry-growing land in Korea, however, belongs to alkaline soils with low organic matter content. As a result, the eco-friendly blueberry growers use peat moss and sulfur powder heavily to improve the soil condition, but the guideline on the effective use of organic materials was not established yet. Therefore, this sturdy was performed to investigate the effect of increasing soil acidity and organic matters by using organic materials. Among 5 organic materials, the pH of soil was lowest in degradable sulfur + bentonite (pH 4.1) and followed by Peat moss+Chaff+Pine Needlesmixtures(pH 4.5), OrganicAcid +vinegar (pH 4.7), Sulfur powder (pH 4.8), Temperature response Elutioner (pH 5.2). The soil organic matter content were increased in the following order: Peat moss+Chaff+Pine Needlesmixtures (8.4%) > degradable sulfur + bentonite (7.8%) > Organic Acid + vinegar (7.2%) > Sulfur powder ${\fallingdotseq}$ Temperature response Elutioner (6.3%). Although different in the degree, all organic materials treated was recognized a good material for improving soil pH and organic matter content. The plant height and stem diameter of blueberry were no clear difference among 5 organic materials. Another study was carried out to investigate amending soils with organic matter by soil mulching with pine needles for soil surface management in blueberry organic cultivation. The effect of increasing the soil pH by pine needle mulching in blueberry eco-friendly farming was recognized in four test fields. Pine needle mulching for soil surface management in blueberry appeared several advantages, such as improving of soil pH and organic matter content. Therefore, pineneedle mulching in blueberry organic farming is considered as the most efficient means of mulching cultivation for amending soil pH, weed suppression and moisture conservation among mulching materials.

• Korean Journal of Environmental Agriculture
• /
• v.14 no.2
• /
• pp.202-212
• /
• 1995

In order to elucidate the degrading characteristics of the pyrethroid acaricide-insecticide, acrinathrin in two different types of soils, Soil A(pH, 5.8; organic matter, 3.4%; C.E.C., 115 mmol(+)/kg soil; texture, sandy loam) and Soil B(pH, 5.7; organic matter, 2.0%; C.E.C., 71 mmol(+)/kg soil; texture, sandy loam), residualities of the non-labeled compound under the field and laboratory conditions, extractability with organic solvents and formation of non-extractable bound residues, and degradabilities of [$^{14}C$]acrinathrin as a function of aging temperature and aging period were investigated. The half lives of acrinathrin in Soil A treated once and twice were about 18 and 22 days and in Soil B about 13 and 15 days, respectively, in the field, whereas, in the laboratory, those in Soil A and B were about 36 and 18 days, respectively, suggesting that the compound would be non-persistent in the environment. The amounts of $^{14}CO_2$ evolved from [$^{14}C$]acrinathrin in Soil A and B during the aging period of 24 weeks were 81 and 62%, respectively, of the originally applied $^{14}C$ activity, and those of the non-extractable soil-bound residues of [$^{14}C$]acrinathrin were about 70% of the total $^{14}C$ activity remaining in both soils, increasing gradually with the aging period. Degradation of [$^{14}C$]acrinathrin in both soils increased with the aging temperature. Three degradation products of m/z 198(3-phenoxy benzaldehyde), m/z 214(3-phenoxybenzoic acid), and m/z 228(methyl 3-phenoxybenzoate) as well as an unknown were detected by autoradiography of acetone extracts of both soils treated with [$^{14}C$]acrinathrin and aged for 15, 30, 60, 90, 120, and 150 days, respectively, and the degradation pattern of acrinathrin was identical in both soils. Acrinathrin in soil turned out to be degraded to 3-phenoxybenzaldehyde cyanohydrin by hydrolytic cleavage of the ester linkage adjacent to the $^{14}C$ with a cyano group, the removal of hydrogen cyanide therefrom led to the formation of 3-phenoxybenzaldehyde as one of the major products, and the subsequent oxidation of the aldehyde to 3-phenoxybenzoic acid, followed by decarboxylation would lead to the evolution of $^{14}CO_2$.