• Title/Summary/Keyword: Fe-Cr

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The Effect of Long-term Application of Different Organic Material Sources on Chemical Properties of Upland Soil (유기물원이 다른 퇴비연용이 밭토양의 화학성 변화에 미치는 영향)

  • Kim, Jong-Gu;Lee, Kyeong-Bo;Lee, Sang-Bok;Lee, Deog-Bae;Kim, Seong-Jo
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.3
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    • pp.239-253
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    • 1999
  • The objective of this study was to determine the effects of various kinds of composts on the change of soil chemical properties in upland soils. Field experiments were conducted in the loam and sandy loam soils. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80Mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : The continuous application of human excrement sludge decreased soil pH up to 4.4~5.0, while other compost treatments increased soil pH compared with control plot. The EC increased initially and showed their maximum values at 20days after compost application, and then decreased up to 40 days, thereafter kept a certain level. The available phosphorous accumulated at 0~20cm depth in loam soil, and 0~50cm in sandy loam soil. Annual accumulation rates were 17% higher in sandy loam soil than loam soil. The more compost application rates and times, the higher base saturation percentage increased in upland soils. Four year's application at a rate of $80Mg\;ha^{-1}$ per year increased the base saturation percentage to 87~91% compared with 45% at control plot in the loam soil. While in sandy loam soil only three year's application of same rate increased the base saturation percentage to 81~92% compared with 30.4% at control plot. The average annual increasing rate of base saturation percentage at the same application rates of composts were higher in sandy loam soil by 2.0~3.7 times than in loam soil. The application of compost increased the exchangeable Ca, Mg, and K contents of soils by 2, 2~3, and 3~5 times, respectively, compared with the control. The contents of exchangeable canons were high in surface soil. and decreased with increase of soil depths. In the case of heavy metal content, there were no difference at the application of PMC and CMC but Ni. Fe, Zn, Cu was increased a little when the HES applied, and Ni and Cr was increased application with FISC.

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Mineral chemistry and texture of the zoned amphiboles of the amphibolites in the Hwanggangri area, the northeastern region of Ogcheon metamorphic belt, Korea (옥천변성대 북동부 황강리 지역내 앰피볼라이트에 나타나는 대상 각섬석의 광물화학 및 조직)

  • 유영복;권용완;김형식
    • The Journal of the Petrological Society of Korea
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    • v.9 no.2
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    • pp.99-118
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    • 2000
  • The variation of Na(A), K, Na(M4), A l O and Al(VI)+Fe3++Ti+Cr in the zonal amphiboles from the amphibolites of the Hwanggangri area indicates that the tschermakite-, edenite- and glaucophane substitutions are higher in the rim than in the core, in which actinolite changes to hornblende with going outward from core to rim. The contents of substitutional elements of hornblende~ of three samples@l29-2, M76-2, M78), which include diopside and greenish brown hornblende and are thought to represent the highest metamorphic grade, are lower than those of rim homblendes of the lower metamorphic grade and are higher than those of core actinolite that they conform to the middle domain in those of the whole amphiboles. Considerations about the origin of zonal amphiboles are as follows. Firstly, two samples(R102-1, R210-9) have the same amphibole composition like core is actinolitic hornblende, and rim is magnesian hastingsite although plagioclases such as albite(R102-1) and labradorite (R210-9) show the wide compositional difference. It is impossible to produce both albite and labradorite by one metamorphic event. Judging from this wide compositional difference, the existence of zonal amphiboles does not indicate the miscibility gap but is thought to be the result of the polymetamorphism. Secondly, the crystallographically sharp and gradational interfaces between actinolite and hornblende fonned in the amphibolites rgardless of the distance from the granite. In case of the samples(R210-9, M128, M130) having the sharp interface between two amphiboles, the plagioclase show the compositions produced at the low grade and the medium grade. Because such variable compositions of plagioclase indicates the overprinting of metamorphism of higher metamorphic grade than that of the formation of miscibility gap, it implies that zonal amphiboles were formed by polymetarnorphism. In case of the gradational interface between two amphiboles, this texture is also thought to be the effect of polymetamorphism from the fact that this texture mainly occur near the granite and from the consideration of the metamporphic grade. The relationship between the compositional variations of the amphiboles and the pressure types of metamorphism suggests that actinolitic core is considered to be grown by the metamorphism of medium pressure, while hornblende rim is shown to have genetic relations with the metamorphism of low pressure type.

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Vertical Distribution of Heavy Metal Concentrations in Sediment Cores and Sedimentation Rate Using $^{210}Pb$ Dating Technique in the Juam Reservoir (주암댐 호저 퇴적물에서의 수직적 중금속 분산과 $^{210}Pb$를 이용한 퇴적속도산정)

  • Lee Pyeong-Koo;Youm Seung-Jun;Yeon Gyu Hun;Chi Se-Jung;Kim Ji-Wook;Oh Chang-Whan;Kim Sun-Ok
    • Journal of Soil and Groundwater Environment
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    • v.10 no.1
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    • pp.43-57
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    • 2005
  • Twelve bottom sediments and three cores were collected in Juam reservoir for a study on transportation, which was controlled by particle grain size (2mm-200{\mu}m,\;200-100{\mu}m,\;100-50{\mu}m,\;50-20{\mu}m,\;<20{\mu}m), and vertical distribution of heavy metals. Sediment cores were sliced into 2 to 5 cm intervals to measure heavy metal concentrations in interstitial water and sediments with depth. Pb isotopic compositions of core samples were determined to calculate sedimentation rate. Regardless of sampling sites, levels of heavy metals and trace elements in bottom sediments are nearly constant with mean values of $14.9\;{\mu}g/g\;for\;As,\;0.81{\mu}g/g\;for\;Cd,\;30.7{\mu}g/g\;for\;Cu,\;34.7{\mu}g/g\;for\;Ni,\;63.3{\mu}g/g\;for\;Pb\;and\;87.9{\mu}g/g\;for\;Zn$. In general, Cu, Pb, Zn, Wi, and Cr in fraction of $<20{\mu}m$ exhibit the highest concentration, but content of As is the highest in grain size of $2\;mm-200\;{\mu}m$ and $200-100\;{\mu}m$. Fe and Mn occur as the dissolved compositions of the highest concentrations in interstitial waters and increase in their concentrations toward lower part of cores. On the contrary, concentrations of Zn and Cu show the highest value in the uppermost part in cores, suggesting these elements are released from reductive dissolution of hydroxides and oxidation of organic matters under different redox conditions. The highest accumulations of Cu, Ni, Pb, and Zn contents in the sediment cores are observed at 0-4 cm layers, and concentrations of Cu and Pb are especially high, implying these heavy metals are originated from anthropogenic sources. The apparent sedimentation rate estimated using unsupported $^{210}Pb$ is 0.91 cm $year^{-1}$, corresponding about 10 cm sedimentation in total depth since construction of Juam dam. These results will provide available information for management of bottom sediment in Juam reservoir.

Geochemical Characteristics of Stream Sediments Based on Bed Rocks in the Cheongpung Area (기반암에 따른 청풍지역 하상퇴적물의 지구화학적 특성)

  • Park, Young-Seog;Park, Dae-Woo;Kim, Jong-Kyun;Song, Yeung-Sang;Lee, Jang-Jon
    • Economic and Environmental Geology
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    • v.39 no.6 s.181
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    • pp.675-687
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    • 2006
  • The purpose of this study is to determine the geochemical characteristics of the stream sediments in the Cheongpung area. So that we can understand the natural background and predict the prospects of geochemical disaster, if any. We collected the stream sediments samples by wet sieving along the primary channels and slow dried the collected samples in the laboratory and ground them to pass a 200 mesh using an alumina mortar and pestle for chemical analysis. Miner-alogical characteristics, major, trace and rare earth elements were determined by XRD, XRF, ICP-AES and NAA analysis methods. For geochemical characteristics on the geological group of stream sediments, the studied area was grouped into granitic gneiss area, metatectic gneiss area, Dado tuff area, Yuchi conglomerate area, and Neungju flow area in the Cheongpung area. Contents of major elements for the stream sediments in the Cheongpung area were $SiO_2\;47.31{\sim}72.81\;wt.%,\;A1_2O_3 \;11.26{\sim}21.88\;wt.%,\;Fe_2O_3\;2.83{\sim}8.39\;wt.%,\;CaO\;0.34{\sim}7.54\;wt.%,\;MgO\; 0.55{\sim}3.59\;wt.%,\;K_2O\;1.71{\sim}4.31\;wt.%,\;Na_2O\;0.56{\sim}2.28\;wt.%,\;TiO_2\;0.46{\sim}1.24\;wt.%,\;MnO\;0.04{\sim}0.27\;wt.%,\;P_2O_5\;0.02{\sim}0.45\;wt.%$. The con-tents of trace and rare earth elements for the stream sediments were $Ba\;700ppm{\sim}8990ppm,\;Be\;1.0{\sim}3.50ppm,\;Cu\;6.20{\sim}60ppm,\;Nb\;12{\sim}28ppm,\;Ni\;4.4{\sim}61ppm,\;Pb\;13{\sim}34ppm,\;Sr\;65{\sim}787ppm,\;V\;4{\sim}98ppm,\;Zr\;32{\sim}164ppm,\;Li\;21{\sim}827ppm,\;Co\;3.68{\sim}65ppm,\;Cr\;16.7{\sim}409ppm,\;Cs\;2.72{\sim}37.1ppm,\;Hf\;4.99{\sim}49.2ppm,\;Rb\;71.9{\sim}649ppm,\;Sb\;0.16{\sim}5.03ppm,\;Sc\;4.97{\sim}52ppm,\;Zn\;26.3{\sim}375ppm,\;Ce\;60.6{\sim}373ppm,\;Eu\;0.82{\sim}6ppm,\;Yb\;0.71{\sim}10ppm$.

Trace element Analysis and Source Assessment of Apartment Parking Lot Dust in Daegu, Korea (공동주택 주차장의 축적먼지 중 미량원소성분 분석과 오염원 평가)

  • Bae, Gun-Ho;Jung, Cheol-Su;Park, Kyu-Tae;Lee, Myoung-Sook;Shin, Dong-Chan;Kim, Yong-Hye;Yoon, Min-Hye;Han, Young-Jin;Choi, Hyuek;Baek, Sung-Ok
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.10
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    • pp.756-766
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    • 2011
  • In order to investigate the degree of apartment parking lot dust contamination, total 72 samples of parking lot dust (36 from ground parking lots and 36 from the underground parking lots) were collected in Daegu city from the end of March to the early June 2010. The dust samples were sieved below $100{\mu}m$, and analysed by ICP for 14 elements after an acid extraction. Results obtained from the source assessment of trace element using enrichment factor showed that Fe, K, Mg, Mn, Na and V were influenced by natural sources, while Cd, Cr, Cu, Ni, Pb and Zn were influenced by anthropogenic sources in both the ground parking lot and the underground parking lot. And results showed that Ca were influenced by natural sources in the ground parking lot, but influenced by anthropogenic sources in the underground parking lot. The measured values were remarkably higher in components from natural sources than in components from anthropogenic sources. Underground parking lot dust was more affected by anthropogenic sources and contaminated compared with the ground parking lot dust. Pollution index of heavy metals revealed that underground parking lot dust was 5.5 times more contaminated with heavy metal components than the ground parking lot dust. The results of correlation analysis among trace elements indicated that components in the ground parking lot were more correlated than those in the underground parking lot, and especially more correlated with natural sources-natural sources. Analysis for correlations between components and influencing factors in the underground parking lot showed that concentrations of heavy metals were higher with smaller number of parking spaces and no ventilation system, and older apartments in last paint and cleaning had relatively higher contents of heavy metals than those of recently painted and cleaned.

Effects of Allium Vegetable Intake on Levels of Plasma Glucose, Lipid and Minerals in Streptozotocin Induced Diabetic Rats (Allium속 식용식물의 섭취가 Streptozotocin 유발 당뇨 흰쥐의 혈당, 지질 및 무기질 수준에 미치는 영향)

  • Ahn, Young-Mi;Lim, Sook-Ja;Han, Hye-Kyoung;Choi, Sung-Sook
    • Journal of Nutrition and Health
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    • v.39 no.5
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    • pp.433-443
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    • 2006
  • The effects of Allium vegetables on blood glucose levels and lipid metabolism in streptozotocin (S12) induced diabetic rats were investigated. Diabetes mellitus was induced by S1'2 injection (45 mg/kg 5.w.) into the tail vein. Sprague-Dawley rats weighing $220\;{\pm}\;10\;g$ were randomly assigned to 7 groups: normal, S1'2-control and five Allium groups (Allium cepa, Allium fistulosum, Allium sativum, Allium tuberosum and Allium victorialisL Normal and S12control groups were fed an AIN-93 diet and five Allium groups were fed a modified diet containing. 10% Allium powder each for 4 weeks. Body weight, diet intake, food efficiency ratio (FER) and organ weights- were monitored. Activities of aspartate aminotransferase (AST) & alanine aminotransferase (ALT) were observed: Plasma lev~ls of glucose, free fatty acid, triglyceride and HDL-cholesterol were analyzed. Levels of glycogen, cholesterol and triglyceride in liver were determined. Levels of malondialdehyde (MDA) in liver, lung, kidney, and pancreas were assayed. The hepatic contents of chromium (Cr) , iron (Fe), zinc (Zn) and manganese (Mu) were measured. The Allium sativum group had weight gain and suppressed a hypertrophy of the kidney significantly. The activity of ALT was significantly lowered in the diabetic groups except Allium sativum group compared to STZ-control group. The Allium sativum and Allium tuberosum groups showed the hypoglycemic effects at 4 weeks. There were no significant differences between the control and all the other diabetic groups in the plasma levels of cholesterol, HDL-cholesterol, triglycerides and free fatty acids. Most of the Allium groups except Allium fistulosum were observed significantly lowered level of MDA in the lung compared to STZ-control group. The diabetic rats fed the Allium cepa and Allium sativum have shown significantly lowered hepatic Zn contents. The results suggested that the intake of the Allium vegetables may be effective in the antihyperglycemia by lowering blood glucose levels.

The Synthetic Study of Environmental Contamination at the Seokdae Municipal Waste Landfill in Pusan (부산 석대 생활폐기물 매립장의 환경오염에 대한 종합적 연구)

  • 김병우;정상용;이민희;이병헌
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.04a
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    • pp.98-103
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    • 2001
  • In order to understand the characteristics of leachate at the Seokdae municipal waste landfill in the Pusan city, the correlation between leachate pollution loading and volume of gas production. concentration of gas and subsidence of ground, the characteristical methos, geochemical analyses and laboratory column tests using samples of gases, leachate and surface soil of Seokdae waste landfill area. Through the analysis of water balance, leachate flow rate and pollution loading were estimated. Geistatistical analysis of four gas components ( $O_2$, C $H_4$, $H_2$S and CO) shows the possibility of ground subsidence around the group of a site with high concentration of gas. From geochemical analyses of leachate, EC and Total-Alkalinity of ground subsidence around the group of a site with high concentration of gas. From geochemical analysis of leachate, Ec and Total-Alkalinity were increased, and Cl, Cr, Mn, Cu, Zn, Cd and Pb were decreassed comparing to the part, and the type of water quality was Na-HC $O_3$ in trilinear diagram. It shows that biodecomposition of municipal wastes continues actively. From the analysis of water balance, the total leachate flow rate is about 465.11㎥/day and pure pollution loading of Cl, Mn and Fe are estimated to 223.8kg/day, 0.2kg/day, 0.3kg/day, respectively. The laboratory column test of residual soil and landfill soil shows 0.206cm and 0.019cm for linear velocity(equation omitted), 0.234 $\textrm{cm}^2$/min and 0.018$\textrm{cm}^2$/min for diffusion coefficient ( $D_{ι}$), and 1.136cm and 0.095cm longitudinal dispersion index ($\alpha$$_{ι}$), respective]y. It demonstrates that the delay time of contamination for residual soil is shorter than that of landfill soil.

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A COMPARATIVE STUDY ON THE PHYSICAL PROPERTIES OF ORTHODONTIC PLIERS ACCORDING TO TYPES OF STERILIZATION (멸균 방법에 따른 교정용 플라이어의 물성 변화에 대한 비교 연구)

  • Cho, Il-Je;Son, Woo-Sung
    • The korean journal of orthodontics
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    • v.28 no.2 s.67
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    • pp.329-341
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    • 1998
  • Sterilization has received much attention in orthodontic practices over the past several years. The present study was undertaken to investigate the effects of sterilization on the physical properties of orthodontic pliers-AEZ, Unitek, and Dentronix ligature cutters. This study was designed to examine the tips of ligature cutters before and after 200 and 400 sterilization cycles using the Bowmar RHT-1000, the Dentronix DDS-5000, and the Eschmann SES-2000. The tip surface and the fracture surface were observed with a scanning electron microscope. The microstructure was observed with an optical microscope. The hardness test was carried out with the mic개-Vickers hardness tester and the Rockwell C Scale hardness tester. The chemical composition was analyzed by energy dispersive X-ray spectrometer. The results of this study were as follows : 1. The number and the size of corrosion products on the tip surface and the proportion of cleavage planes in fractured specimen increased, but the hardness of the tip decreased in proportion to sterilization cycles. From these observations, it was considered that mechanical properities decreased in proportion to sterilization cycles. 2. The number and the size of chromium carbides increased in proportion to sterilization cycles. Coarse microstructure decreased mechanical properities. 3. The AEZ and Unitek ligature cutters were Fe-Cr stainless steels, but the Dentronix ligature cutter was Co-Cr alloy. There were many differences among manufactures, but the chemical composition was .not changed after sterilization cycles. 4. The tip edge of ligature cutter used in a clinic revealed microcracks with the SEM observation. Clinical experience confirmed that ligature cutters were gradually degraded by sterilization.

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Low-temperature Oxidation of Odor Compounds over La-based Perovskite Catalyst (란탄 기반 페롭스카이트 촉매를 이용한 악취 유발 물질의 저온 산화 반응)

  • Bang, Yong-Ju;Seo, Jeong-Gil;Lee, Gi-Chun;Park, Chan-Jung;Kim, Hyung-Tae;Song, In-Kyu
    • Korean Chemical Engineering Research
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    • v.49 no.2
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    • pp.168-174
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    • 2011
  • Various La-based perovskite catalysts were prepared by a Pechini method, and they were applied to the low-temperature oxidation of odor compounds exhausted from waste food treatment process for effective deodorization. Quantitative and qualitative analyses of exhausted gas were conducted to measure the amount of major odor compounds with respect to operation time. A standard odor sample composed of major odor compounds was then prepared for use as a feed for oxidation reaction system. Various transition metal(M)-substituted La-based perovskite catalysts ($LaMO_{3}$: M=Cr, Mn, Fe, Co, and Ni) were prepared and applied to the oxidation of odor compounds in order to investigate the $LaNiO_3$ catalyst showed the best catalytic performance. Pt-substituted perovskite catalysts ($LaNi_{1-x}Pt_{x}O_{3}$: x=0, 0.03, 0.1, and 0.3) were then prepared for enhancing the catalytic performance. It was found that $LaNi_{0.9}Pt_{0.1}O_{3}$ catalyst served as the most efficient catalyst. Supported perovskite catalysts ($XLaNi_{0.9}Pt_{0.1}O_{3}/Al_{2}O_{3}$: X=perovskite content(wt%), 0, 10, 20, 30, 40, 50, and 100) were finally applied for the purpose of maximizing the catalytic performance of perovskite catalyst in the low-temperature oxidation reaction. Catalytic performance of $XLaNi_{0.9}Pt_{0.1}O_{3}/Al_{2}O_{3}$ catalysts showed a volcano-shaped curve with respect to perovskite content. Among the catalysts tested, $20LaNi_{0.9}Pt_{0.1}O_{3}$/$Al_{2}O_{3}$ catalyst exhibited the highest conversion of odor compounds of 88.7% at $180^{\circ}C$.

Physio-Chemical Characteristics of Soil, Stream Sediment and Soil Water Contaminated by the Abandoned Coal Mine in Keumsan, Chungnam (충남(忠南) 금산(錦山) 폐탄광지역(廢炭鑛地域)의 토양(土壤), 하상퇴적물(河床堆積物) 및 토양수(土壤水)의 이화학적(理化學的) 특성(特性))

  • Min, Ell Sik;Kim, Myung Hee;Song, Suckhwan
    • Journal of Korean Society of Forest Science
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    • v.86 no.3
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    • pp.324-333
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    • 1997
  • The research has been made for the effects of the pollution by the abandoned coal mine drainage on the physical and chemical properties of soil, stream sediment and soil water. The soils overspreaded by the abandoned coal don't develop solum and the bulk density is $1.83g/m^3$, compared with $1.14-1.38g/m^3$ in the other forest soils. The soil pH range in coal bearing region ie, from 4.01 to 4.11 and non-coal bearing soil range is from 5.03 to 5.13. Heavy metals such as As, Cr, Ni, Mo and Ba of coal bearing soils and polluted stream sediments have larger concentration than those of non-coal content and non-polluted. Especially As and Mo concentrations are largely high in coal bearing. The relative ratios $K_2O/Na_2O$ of geochemical elements are higher in coal bearing soil and polluted stream sediments than those of non-coal bearing soils and non-polluted stream sediments as well as black shales of the Changri Formation. However, $MgO+Fe_2O_3+TiO_2/CaO+K_2O$ are the opposite trends, so that the ratios are lower in the polluted regions. The soil water pHs in the polluted regions are the strong acid(pH3.4-4.2) and buffer capacity of the polluted soil is low because canons such as $Na^+$, $K^+$, $Mg^{+2}$are leached by the acidification.

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