• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.491-498
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• 2005

Acid Rock Drainage(ARD) is the product formed by the atmospheric(i.e. by water, oxygen and carbon dioxide) oxidation of the relatively common iron-sulphur minerals pyrite($FeS_2$). ARD causes the acidification and heavy metal contamination of water and soil and the reduction of slope stability. In this study the generation characteristics and the prediction of ARD of various road cut slopes were studied. An attempt to classify the rocks into several groups according to their acid generation potentials was made. Acid Base Accounting(ABA) tests, commonly used as a screening tool in ARD predictions, were performed. Sixteen rock samples were classified into PAF(potentially acid forming) group and four rock samples into NAF(non-acid forming) group. The chemical analysis of water samples strongly suggested that ARD with high content of heavy metals and low pH could pollute the ground water and/or stream water.

• Journal of Microbiology
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• v.37 no.4
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• pp.200-205
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• 1999

7-Aminocephalosporanic acid (7-ACA) is the initial compound in preparation of cephalosporin antibiotics widely used in clinical treatment. Bacteria producing glutaryl 7-ACA acylase, which convert cephalosporin C to 7-ACA, has been screened in soil samples. A bacterial strain exhibiting high glutaryl 7-ACA acylase activity, designated KAC-1, was isolated and identified as a strain of Pseudomonas diminuta by characterizing its morphological and physiological properties. The screening procedures include culturing on enrichment media containing glutaric acid, glutamate, and glutaryl 7-aminocephalosporanic acid as selective carbon sources. To enhance enzyme production, optimal cultivation conditions were investigated. This strain grew optimally at pH 7 to 9 and in temperatures of 20 to 40 C, but acylase production was higher when the strain was grown at 25 C. Glutaric acid, glutamate and glucos also acted as inducers for acylase production. In a jar fermenter culture, P. diminuta KAC-1 produce acylase in a growth-associated manner. The substrate specificity of KAC-1 acylase by cell extract showed that this enzyme had specificity toward glutaryl 7-ACA, glutaryl 7-ADCA, but not cephalosporin C.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.217-222
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• 1996

A green-house experiment was conducted to know the performance of Chinese cabbage and radish applied with simulated acid rain(SAR) on the leaf and/or soil. The pHs of SAR and normal water were 2.7 and 6.0, respectively. The pHs of SAR and normal water applied on leaf/soil were 6.0/6.0, 6.0/2.7, 2.7/6.0, and 2.7/2.7 and they were applied fifteen times at the two- or three-day intervals with 10mm at a time. Leaf application of SAR caused brown spots in both crops, while no such symptoms were observed in soil application. SAR applied on the leaf or soil increased chlorophyll content significantly in Chinese cabbage, but slightly in radish. Leaf or soil application of SAR did not affect N, P, and K concentrations in both crops. The sulfur content in radish leaf increased by leaf or soil application of SAR, while in the root it increased by soil application only. Yield of Chinese cabbage was not affected by SAR, while both leaf and root yields of radish were significantly reduced by leaf application of SAR compared with soil application.

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.13-17
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• 2005

Potential for measuring mobile cadmium concentration in sandy soil using polymer magnetic beads with carboxyl groups was investigated. Experiments for extracting cadmium were performed with contaminated soils, de-ionized water and magnetic beads. In this neutral experimental condition, reacting cadmium with magnetic beads indicate total amount of cadmium that can be moved in soil. The results showed that the mobile fraction of cadmium in soil could be combined with magnetic beads in short time. After binding between cadmium and magnetic beads, the beads were separated from soil suspension by outer magnetic force. The bound cadmium was dissolved from magnetic beads by acid solutions, which were then analyzed by atomic absorption spectroscopy (AAS). This method can determine mobile heavy metals in sandy soil effectively than existing method which use pollutant chemicals to environments such as EDTA.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.483-492
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• 1986

To find out the responses of plant growth, nodulation, and yield of soybean and their varietal differences to different soil pH, 16 soybean cultivars were examined under three different levels of soil pH. In general, as the soil pH decreased, plant growth, nodulation, yield and yield component and protein con-tents of grains were decreased in most of cultivars studied. But there were significant varietal differences in the responses of the characters investigated to soil pH. Jangbaegkong was evaluated as the most tolerant cultivar to acid soil, and Ulsan, Bongeui, Hwanggeumkong, and LC7852 were also relatively torelant to acid soil. There were significant correlation between soil pH and grain yield in 7 cultivars among 16, but were not in other cultivars.

• Applied Biological Chemistry
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• v.26 no.4
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• pp.239-247
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• 1983

The effects of some soil conditions on the degradation rate and decomposing pattern of parathion were investigated and the obtained results are summarized as follows: Parathion degraded more rapidly in flooded soils than in non-flooded, in wet soils than in dry soils under non-flooded soils. The degradation rates in paddy and upland soils increased at high temperature than low temperature, higher pesticide concentration than low concentration and higher soil pH level. Parathion in paddy and upland soils was more persistent under soil sterilization than under non-sterilization and degraded rapidly in glucose application. Parathion was more persistent in upland soils than paddy soils under several factors described above. The metabolites identified from the paddy and upland soils by TLC include para-oxon (Rf 0.5), aminoparathion(Rf 0.27), p-nitrophenol(Rf 0.2), p-aminophenol(Rf 0.15). Soil enzyme, acid phosphatase activities decreased more at flooded soils than non-flooded, higher pesticide concentration than low concentration and higher soil pH level and the activity in glucose application was increased. Soil enzymes, urease and dehydrogenase activity decreased more at higher pesticide concentration than low concentration. Comparing with soil enzyme activity in paddy and upland soil, the former was higher than the latter.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.492-497
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• 2011

Soil management for orchard depends on the effects of soil microbial activities. The present study evaluated the soil microbial community of 25 orchard in Gyeongnam Province by fatty acid methyl ester (FAME) method. The average concentrations in the orchard soils were $332nmol\;g^{-1}$ of total FAMEs, $94nmol\;g^{-1}$ of bacteria, $46nmol\;g^{-1}$ of Gram-negative bacteria, $42nmol\;g^{-1}$ of Gram-positive bacteria, $4.8nmol\;g^{-1}$ of actinomycetes, $54nmol\;g^{-1}$ of fungi, and $9.1nmol\;g^{-1}$ of arbuscular mycorrhizal fungi. In addition, sandy loam soils had significantly low ratio of cy19:0 to 18:$1{\omega}7c$ compared with that of loam soils (p<0.05), indicating that microbial stress decreased. The average soil microbial communities in the orchard soils were 28.1% of bacteria, 15.9% of fungi, 13.6% of Gram-negative bacteria, 12.5% of Gram-positive bacteria, 2.8% of arbuscular mycorrhizal fungi, and 1.4% of actinomycetes. The soil microbial community of Gram-negative bacteria in peach cultivating soils was significantly higher than that of pear cultivating soils (p<0.05).

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.375-383
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• 2020

BACKGROUND: Bisphenol A (BPA) is a chemical widely used in polycarbonate plastics, epoxy resins. BPA is an endocrine disruptor. Residue of BPA in agricultural environments is a major concern. The objective of this study was to understand the characteristics of the uptake and distribution of BPA and its metabolites introduced into the agricultural environment to crops, and to use it as basic data for further research on reduction of BPA in agricultural products. METHODS AND RESULTS: This study established the analysis method of BPA and its metabolites in soil and crops, and estimated the intake of BPA and its metabolites from lettuce (Lactuca sativa) grown in sandy loam and loam soil, which are representative soils in Korea. The two major metabolites of BPA were 4-hydroxyacetophenone (4-HAP) and 4-hydroxybenzoic acid (4-HBA). BPA, 4-HAP and 4-HBA have been analyzed by using liquid chromatography tandem mass spectrometry (LC-MS/MS). These substances were detected in sandy loam and loam soil, indicating that certain portions of BPA were converted to 4-HAP and 4-HBA in the soil; however, it was observed that only 4-HBA migrated to lettuce through the roots into crops. CONCLUSION: The uptake residues showed the BPA and 4-HAP were not detected in lettuces grown on sandy loam (SL) and loam (L) soil treatments that were applied with of 10 ng/g, 50 ng/kg and 500 ng/g of BPA. However, the 4-HBA was detected at the level of 7 ng/g and 11 ng/g in the lettuce grown in sandy loam and loam soil that were treated with the 500 ng/g of BPA, respectively, while the 8 ng/g of 4-HBA was measured in the lettuce cultivated in the loam that was treated with 100 ng/g of BPA. This result presents that the BPA persisting in the soil of the pot was absorbed through the lettuce roots and then distributed in the lettuce leaves at the converted form of 4-HBA, what is the oxidative metabolite of BPA.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.531-536
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• 2011

This study was conducted to investigate the effects of cultural soil textures on growth and quality of Glycyrrhiza uralensis Fischer from 2009 to 2010. The obtained results from this study were summarized as follows; The growth of stem and leaf were superior to one year old G. uralensis, and surface runner and root growth tended to be better in 2 years old G. uralensis. The weight of stem and leaf were heavy in sandy loam, and plant height, branches, stem diameter in sandy clay loam were better than other soil texture. The growth characteristics, such as length, number and weight of surface runner, was better in order of sandy clay loam > sandy loam > loamy sand. The length of main and lateral root was longer in loamy sand soil than other treatments, and the diameter of main and lateral root was more thicker in sandy loam than others. The number of lateral root was higher in the sandy loam than other treatments. The yield of main and lateral root was in order of sandy loam > sandy clay loam > loamy sand soil. Marketable root yield of one year old and two year old G. uralensis were increased 57% and 71% in sandy loam compare to a loamy sand as 204 kg/10 a, respectively. The content of glycyrrhizinic acid was the hightest as 1.62% in sandy clay loam soil in one year old, and as 1.58% in sandy loam soil in two years old of G. uralensis, respectively.

• The Korean Journal of Food And Nutrition
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• v.1 no.1
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• pp.3-6
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• 1988

For the purpose of the production of yeast cell protein from rice bran oil, it's assimillating yeast(E222) was isolating from soil and the resulting of identification was shown that it was belonging to Candida aibican species Total free amino acids from yeast cells were shown 0.05% per gram. Nine other species of amino acids as well as glycine, glutamic acid, alanine, leucine and aspartic acid were produced from yeast cells.