• Title/Summary/Keyword: Acid Soil

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Experimental Studies on Dissolution Characteristics of a Heavy Metal(As) in Mining Waste (광산매립지에서 중금속(As)의 용출 특성에 관한 실험적 연구)

  • Han, Choon;Seo, Myoung-Jo;Yoon, Do-Young;Choi, Sang-Il;Lee, Hwa-Young;Kim, Sung-Kyu;Oh, Jong-Kee
    • Journal of Korea Soil Environment Society
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    • v.3 no.1
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    • pp.55-63
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    • 1998
  • This study investigates the contamination mechanism of soil by drainages including acid rains around mining waste sites, and suggests the quantitative methods of prevention against soil contaminations and its alternatives. For these purposes, the dissolution of arsenic in soils, which is one of toxic heavy metals, has been examined experimentally using the artificial acidic solution. Also, in order to prevent dissolution of arsenic by acid rain, the effects of limestone for the neutrality method on the soil were investigated. The arsenic in soil specimen was dissolved by strong acidic solution below pH1.0. The maximum amount of dissolved arsenic increased with decreasing pH value. Furthermore, it was found very effective to use limestones for the neutrality method. The neutralization of limestones in acidic solution was found to follow the equation of chemical reaction-controlling formulation in unreacted-core models.

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Consideration on the Scientific Analysis of Ancient Soil (고대 토양의 과학적 분석에 대한 고찰)

  • Seo, Min-Seok;Kim, Min-Hee;Chung, Yong-Jae
    • Korean Journal of Heritage: History & Science
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    • v.37
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    • pp.309-326
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    • 2004
  • There are some methods such as fatty acid analysis and microscope analysis of parasite egg and pollen and genetic analysis of ancient bacteria from ancient soil. The fatty acid analysis can examine whether some materials is human feces or animals. This is important thing to reconstruct ancient toilet culture pattern. The methods using TLC and GC-MS as organic chemistry is able to confirm ancient diet life style and nutritive conditions. The microscope analysis of ancient soil is able to confirm ancient parasite egg and pollen. It is possible to analogize ancient human diseases from this analysis. Also, genetic analysis is able to confirm genetic diversity and variation pattern of ancient organisms in archeological soil. Most of all, it is convinced of carrying through genetic preservation of exterminated ancient organisms. If archeological soils should be analysed through the natural scientific methods such as organic chemistry, soil science, microbiology, molecular biology, and genetics, this is helpful for us to understand and interpretation past historic event. And it is expected to perform an major role for understanding origin of ancient human and life style.

Analysis of Soil Microbial Communities Formed by Different Upland Fields in Gyeongnam Province

  • Kim, Min Keun;Ok, Yong Sik;Heo, Jae-Young;Choi, Si-Lim;Lee, Sang-Dae;Shin, Hyun-Yul;Kim, Je-Hong;Kim, Hye Ran;Lee, Young Han
    • Korean Journal of Soil Science and Fertilizer
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    • v.47 no.2
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    • pp.100-106
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    • 2014
  • The present study investigated variations in soil microbial communities by fatty acid methyl ester (FAME) and the chemical properties at 24 sites of upland soils in Gyeongnam Province. The electrical conductivity of the soil under potato cultivation was significantly higher than those of the red pepper and soybean soils (p < 0.05). The gram-negative bacteria community in potato soil was significantly lower than those in the garlic and soybean soils (p < 0.05). The communities of actinomycetes and arbuscular mycorrhizal fungi in the red pepper soil were significantly higher than those in the potato soil (p < 0.05). In addition, the cy17:0 to 16:$1{\omega}7c$ ratio was significantly lower in red pepper, soybean, and garlic soils compared with potato soil, indicating that microbial stress decreased. Consequently, differences in soil microbial community were highly associated with cultivated crop species, and this might be resulted from the difference in soil chemical properties.

Soil Physico-chemical Properties of Organic Grapes Farms with Different Culture Facilities and Soil Management Practices

  • Kim, Sun-Kook;Kim, Byeong-Sam;Kang, Beom-Ryong;Yang, Seung-Koo;Kim, Byeong-Ho;Kim, Hee-Kwon;Kim, Hyun-Woo;Choi, Kyeong-Ju
    • Korean Journal of Soil Science and Fertilizer
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    • v.46 no.5
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    • pp.399-407
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    • 2013
  • Organic grape was generally produced in rainshield or plastic greenhouse culture while most of fruits were produced in open field. But little attention has been given to soil properties with different culture facilities in organic grape cultivation. This study was conducted to investigate soil physico-chemical properties of organic grapes farms with different culture facilities and soil management practices. Organic fertilizer was main resource to manage soil at organic grapes farms. Organic grapes farms were applied with total amount of organic fertilizer at one time, either at basal or additional fertilization, whereas conventional grapes farms applied with split fertilization. Bulk density and penetration resistance of soil were lower at both rainshield and green manure-applied plastic greenhouse cultures than those at clean plastic greenhouse culture. Especially, in plastic greenhouse, sod culture with natural weed after green manure application was more effective than general sod culture in improving physical properties of the rhizosphere. The contents of organic matter, available phosphate and exchangeable potassium tended to increase in the soils applied with green manure, and the difference of soil chemical properties were significant between rainshield and plastic greenhouse cultures. The optimum soil management was required in plastic greenhouse because pH, available phosphate and exchangeable cations reached over optimum range. Consequently, the ground cover management is the key factor to affect the chemical properties as well as soil physical properties extensively in plastic greenhouse. It is found that sod culture with natural weed after green manure application resulted in enhancement of utilization efficiency of nitrogen, phosphoric acid and potassium in soil in comparison with general sod culture.

Assessment on the Transition of Arsenic and Heavy Metal from Soil to Plant according to Stabilization Process using Limestone and Steelmaking Slag (석회석과 제강슬래그를 이용한 오염토양 안정화에 따른 비소 및 중금속의 식물체 전이도 평가)

  • Koh, Il-Ha;Lee, Sang-Hwan;Lee, Won-Seok;Chang, Yoon-Young
    • Journal of Soil and Groundwater Environment
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    • v.18 no.7
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    • pp.63-72
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    • 2013
  • This study estimated stabilization efficiency of As and heavy metal contaminated agricultural soil in abandoned mine through pot experiment. Also contaminants uptake of plant (lettuce) was compared as function of amendment (limestone, steelmaking slag and the mixture of these) addition. In soil solution analysis, concentration of contaminants in soil solutions which added limestone or steelmaking slag were lower than that of the mixture. Especially in As analysis, concentration with 5% (wt) addition of steelmaking slag showed the lowest value among those with other amendments. This seems that As stabilization happens through Fe adsorption during precipitation of Fe by pH increasing. Leachability of As in stabilized soil by TCLP was represented similar result with soil solution analysis. However leachability of heavy metals in stabilized soil was similar with that of non-stabilized soil due to dissolution of alkali precipitant by weak acid. Contaminants uptake rate by plant was also lower when limestone or steelmaking slag was used. However this study revealed that concentration of contaminants in soil solution didn't affect to the uptake rate of plant directly. Because lower $R^2$ (coefficient of determination) was represented in linear regression analysis between soil solution and plant.

Effects of Soil Organic Amendment as Plant Growing Media Component for Restoration of Planting Ground (식재기반 복원을 위한 유기질계 토양개량재의 효용성)

  • Ju, Jin-Hee;In, Da-Young;Kim, Won-Tae;Yoon, Young-Han;Choi, Eun-Young
    • Journal of Environmental Science International
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    • v.24 no.11
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    • pp.1363-1370
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    • 2015
  • This study was aimed to determine effects of soil organic amendment as plant growing media component on restoration of planting ground. The changes of soil physical and chemical properties and germination and growth of kentucky bluegrass (Poa pratensis L.) were investigated. For treatments, soil was excavated at depth of 0-50 cm (referred as $S_1$) and at depth of 50-100 cm (referred as $S_2$). Then the half amount of $S_1$ soil was mixed with the soil organic amendment (coir dust 40% (v/v), bottom ash 25%, leaf mold 25%, vermiculite 5%, carbonized rice hull 5%) at a rate of 6% (v/v) (referred as $S_1CC$) and also the half amount of $S_2$ soil was mixed with the soil organic amendment at a rate of 6% (v/v) (referred as $S_2CC$) on pot in a 16 cm diameter and 14 cm height. The experiment was replicated 3 times with 3 pots per replication in randomized block design, and 100 seeds were planted per pot. In results, there was no significant difference in soil pH among the treatments with a slight decrease in soil hydraulic conductivity. However, in the $S_1CC$ treatment, positive increases in soil chemical properties, including electrical conductivity, organic matter, phosphoric acid, total nitrogen, exchangeable cation, and cation exchange capacity. Also, the germination rate, plant height, and number of leaves were higher in the $S_1CC$ treatment than those in other treatments. These results suggest that the addition of organic amendment to the soil at depth of 0-50 cm might be proper for restoring planting ground.

Microbial Community Changes in the Soil of Plastic Film House as Affected by Anaerobic Fermentation of Rice Bran or Wheat Bran (쌀겨와 밀기울의 토양 혐기발효 처리가 시설 재배지 토양의 미생물상에 미치는 영향)

  • Kim, Hong-Lim;Weon, Hang-Yeon;Sohn, Bo-Kyun;Choi, Young-Hah;Kwack, Young-Bum
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.5
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    • pp.341-347
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    • 2009
  • Soil microbial community has been changed after the treatment of anaerobic fermentation using wheat bran or rice bran was applied to the soil. In the dilution plate technique, the number of anaerobic bacteria and fungi was higher in rice bran-treated soil than in non and wheat bran-treated soil, but of yeast was higher in wheat bran-treated soil than in non and rice bran-treated soil. Specially, the fungi were not detected in the wheat bran-treated soil. Identified by 16S rDNA sequencing, the number of aerobic bacteria was similar in all treatments, the dominant bacteria was the genus Bacillus. In the phospholipid fatty acid (PLFA) technique, both Gram-positive and Gram-negative bacteria change slightly in all treatments for 20 days of fermentation process but, after 20day, increased rapidly in wheat or rice bran-treated soil. In conclusion, the microbial communities structure was dramatically changed after the treatment of wheat or rice bran to soil.

Elucidation of Environment Factors Affecting the Differences in the Half-Life of the Insecticide Cyfluthrin in Soil between Field and Laboratory Tests (포장과 실내실험에서 살충제 Cyfluthrin의 토양 중 반감기 차이에 미치는 환경요인 구명)

  • Lim, Bang-Hyun;Lim, Yo-Sup;Choi, Yong-Hwa;Han, Seong-Soo
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.291-297
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    • 2000
  • This study was conducted to find out the environmental factors affecting the differences in the half-life of the insecticide cyfluthrin in soil between field and laboratory tests carried out in 1998. Degradation and leaching of cyfluthrin in soil were examined under various environmental conditions that were considered to affect the residuality. Cyfluthrin was degraded 1.9 times faster in non-sterilized soil than in sterilized soil and 1.2 times at $25^{\circ}C$ than at $15^{\circ}C$. The half-lives of cyfluthrin were 61.4 days under the dark condition and 4.5 days under sunlight, and those were 11.8 days under the open condition and 23.8 days under the closed condition. The half-lives of the authentic compound and the commercial product of cyfluthrin were 15 and 1 day in the field test and 26 and 3 days in the laboratory test, respectively. Cyfluthrin was rapidly degraded with an increase in soil moisture content and decomposed faster in the alkaline solution of pH 12 than in the acidic solution of pH 3, but the half-life of cyfluthrin did not make any difference between pH 6.4 of the field test soil and pH 5.6 of the laboratory test soil. Cyfluthrin was immobile in soil from the results that $81{\sim}94%$ of the initial amount remained in the $0{\sim}2\;cm$ layer of the soil column regardless of the amount and time of rainfall after the chemical treatments. From viewing the abovementioned results, soil moisture content, sunlight and formulation type affected greatly soil microbes and volatilization affected slightly, and temperature, pH and rainfall did not affect the big difference in the half-life of cyfluthrin in soil between the field and laboratory tests in the year of 1998.

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Effect of Lime on Growth of Rice and Changes in pH, Eh, Fe2+ and Al in an Acid Sulfate Soil (특이산성토양에서 석회시용이 벼의 생육과 토양의 pH, Eh, Fe2+, Al 변화에 미치는 영향)

  • Park, Nae Joung;Park, Young Sun;Kim, Yung Sup
    • Korean Journal of Soil Science and Fertilizer
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    • v.4 no.2
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    • pp.167-175
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    • 1971
  • A pot experiment with an acid sulfate soil from Kimhae was carried out to find out the cause of toxicity in rice plant. The effect of liming on changes in pH, Eh, Al, and $Fe^{2+}$ in soil and leachate was examined at two-week interval during the growth of rice. Also, total $P_2O_5$, $SiO_2$, Fe and Al contents in plants at harvesting stage were determined. In the early stage, the rice plant in the check soil showed the same healthy growth as did in limed soil even at high Al in soil and leachate. Around panicle forming stage, reddish brown mottlings suddenly infested all over the plants when accompanied with strong reduction, and afterward growth was severely retarded, and finally caused the significant difference in yield. During the strong reduction, significant amount of sulfide was formed only in check soils, but no free $H_2S$ was detected. Appreciable Al was still present in soil and leachate, and $Fe^{2+}$ in check soil was lower than that in limed soil, but $Fe^{2+}$ in leachate was slightly higher. Limed soils were more reduced and produced more $Fe^{2+}$ due to increased microorganism activity in the neutral pH. In the leachate, the check showed slightly higher $Fe^{2+}$ concentration but considerably higher than limed one at later stage. Appreciable amount of Al was detected only in check soil and leachate from transplanting to panicle formation stage. Plant tissues at harvesting stage contained very low P regardless of liming. Uptake of Si was markedly increased by liming. Contents of Fe an Al was markedly higher in check than limed one, but difference in Fe content was more drastic possibly due to more Fe uptake in presence of markedly higher $Fe^{2+}$ in soil and leachate at later growing stage. In conclusion toxic symptom in this acid sulfate soil seems to be primarily due to Al when accompanied with low pH and strong reduction. But association with $Fe^{2+}$ toxicity is not completely excluded. In order to differentiate the effect of $Fe^{2+}$ from that of Al more detailed plant analysis at different stage is required.

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The Alterations of Geochemical Behavior of Arsenic in Stabilized Soil by the Addition of Phosphate Fertilizer (인산질 비료에 의한 안정화 적용 토양 내 비소의 지구화학적 거동 변화)

  • Jeon, Yong-Jung;Kim, Bun-Jun;Ko, Ju-In;Ko, Myoung-Soo
    • Economic and Environmental Geology
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    • v.55 no.2
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    • pp.209-217
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    • 2022
  • The purpose of this study was to confirm the dissolution of arsenic from the stabilized soil around abandoned coal mines by cultivation activities. Experimental soils were collected from the agricultural field around Okdong and Buguk coal mines, and the concentration of arsenic in the soil and the geochemical mobility were confirmed. The average arsenic concentration was 20 mg/kg. The soil with relatively high geochemical mobility of arsenic in the soil was used in the batch and column experiment. The limestone was mixed with soil for soil stabilization, and the mixing ratio was 3% of limestone, based on the soil weight. The phosphoric acid fertilizer (NH4H2PO4) was added to the soil to simulate a cultivation condition according to the Rural Development Administration's rules. Comparative soil without mixing limestone was prepared and used as a control group. The arsenic extraction from soil was increased following the fertilizer mixing amount and it shows a positive relationship. The concentration of phosphate in the supernatant was relatively low under the condition of mixing limestone, which is determined to be result of binding precipitation of phosphate ions and calcium ions dissolved in limestone. Columns were set to mix phosphoric acid fertilizers and limestone corresponding to cultivation and stabilization conditions, and then the column test was conducted. The variations of arsenic extraction from the soil indicated that the stabilization was effectible until 10 P.V.; however, the stabilization effect of limestone decreased with time. Moreover, the geochemical mobility of arsenic has transformed by increasing the mobile fractions in soil compared to initial soil. Therefore, based on the arsenic extraction results, the cultivation activities using phosphoric fertilizer could induce a decrease in the stabilization effect.