[Soil basal respiration and enzyme activities in the root-layer soil of tea bushes in a red soil].

Science.gov (United States)

Yu, Shen; He, Zhenli; Zhang, Rongguang; Chen, Guochao; Huang, Changyong

2003-02-01

Soil basal respiration potential, metabolic quotient (qCO2), and activities of urease, invertase and acid phosphomonoesterase were investigated in the root-layer of 10-, 40-, and 90-yr-old tea bushes grown on the same type of red soil. The soil daily basal respiration potential ranged from 36.23 to 58.52 mg.kg-1.d-1, and the potentials in the root-layer of 40- or 90-yr-old were greater than that of 10-yr old tea bushes. The daily qCO2, ranging from 0.30 to 0.68, was in the reverse trend. The activities of test three enzymes changed differently with tea bushes' age. Urease activity in the root-layer of all age tea bushes ranged from 41.48 to 47.72 mg.kg-1.h-1 and slightly decreased with tea bushes' age. Invertase activity was 189.29-363.40 mg.kg-1.h-1 and decreased with tea bushes' age, but its activity in the root-layer of 10-year old tea bushes was significantly greater than that in the root-layer soil of 40- or 90-year old tea bushes. Acid phosphomonoesterase activity (444.22-828.32 mg.kg-1.h-1) increased significantly with tea bushes' age. Soil basal respiration potential, qCO2 and activities of 3 soil enzymes were closely related to soil pH, soil organic carbon, total nitrogen and C/N ratio, total soluble phenol, and microbial biomass carbon, respectively.

Phosphorus status and sorption characteristics of some calcareous soils of Hamadan, western Iran

Science.gov (United States)

Jalali, Mohsen

2007-10-01

Phosphorus (P) application in excess of plant requirement may result in contamination of drinking water and eutrophication of surface water bodies. The phosphorous buffer capacity (PBC) of soil is important in plant nutrition and is an important soil property in the determination of the P release potential of soils. Phosphorus sorption greatly affects both plant nutrition and environmental pollution. For better and accurate P fertilizer recommendations, it is necessary to quantify P sorption. This study was conducted to investigate available P and P sorption by calcareous soils in a semi-arid region of Hamadan, western Iran. The soil samples were mainly from cultivated land. Olsen’s biocarbonate extractable P (Olsen P) varied among soils and ranged from 10 to 80 mg kg-1 with a mean of 36 mg kg-1. Half of the soils had an Olsen P > 40 mg kg-1 and >70% of them had a concentration >20 mg kg-1, whereas the critical concentration for most crops is potato (44 kg kg-1) fields than in dry-land wheat farming (24 mg kg-1), pasture (30 mg kg-1), and wheat (24 mg P kg-1) fields. A marked increase in fertilizer P rates applied to agricultural soils has caused P to be accumulated in the surface soil. Phosphate sorption curves were well fitted to the Freundlich equation. The standard P requirement (SPR) of soils, defined as the amount of P sorbed at an equilibrium concentration of 0.2 mg l-1 ranged from 4 to 102 mg kg-1. Phosphorus buffer capacity was relatively high and varied from 16 to 123 l kg-1 with an average of 58 l kg-1. In areas of intensive crop production, continual P applications as P fertilizer and farmyard manure have been used at levels exceeding crop requirements. Surface soil accumulations of P are high enough that loss of P in surface runoff and a high risk for P transfer into groundwater have become priority management concerns.

Remediation of Cd-contaminated soil around metal sulfide mines

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Lu, Xinzhe; Hu, Xuefeng; Kang, Zhanjun; Luo, Fan

2017-04-01

The mines of metal sulfides are widely distributed in the southwestern part of Zhejiang Province, Southeast China. The activities of mining, however, often lead to the severe pollution of heavy metals in soils, especially Cd contamination. According to our field investigations, the spatial distribution of Cd-contaminated soils is highly consistent with the presence of metal sulfide mines in the areas, further proving that the mining activities are responsible for Cd accumulation in the soils. To study the remediation of Cd-contaminated soils, a paddy field nearby large sulfide mines, with soil pH 6 and Cd more than 1.56 mg kg-1, five times higher than the national recommended threshold, was selected. Plastic boards were deeply inserted into soil to separate the field and make experimental plots, with each plot being 4 m×4 m. Six treatments, TK01˜TK06, were designed to study the effects of different experimental materials on remediating Cd-contaminated soils. The treatment of TK01 was the addition of 100 kg zeolites to the plot; TK02, 100 kg apatites; TK03, 100 kg humid manure; TK04, 50 kg zeolites + 50 kg apatites; TK05, 50 kg zeolites + 50 kg humid manure; TK06 was blank control (CK). One month after the treatments, soil samples at the plots were collected to study the possible change of chemical forms of Cd in the soils. The results indicated that these treatments reduced the content of available Cd in the soils effectively, by a decreasing sequence of TK04 (33%) > TK02 (25%) > TK01 (23%) > TK05 (22%) > TK03 (15%), on the basis of CK. Correspondingly, the treatments also reduced the content of Cd in rice grains significantly, by a similar decreasing sequence of TK04 (83%) > TK02 (77%) > TK05 (63%) > TK01 (47%) > TK03 (27%). The content of Cd in the rice grains was 0.071 mg kg-1, 0.094 mg kg-1, 0.159 mg kg-1, 0.22 mg kg-1 and 0.306 mg kg-1, respectively, compared with CK, 0.418 mg kg-1. This experiment suggested that the reduction of available Cd in the soils is

Evaluation of methyl bromide alternatives efficacy against soil-borne pathogens, nematodes and soil microbial community.

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Hongwei Xie

Full Text Available Methyl bromide (MB and other alternatives were evaluated for suppression of Fusarium spp., Phytophthora spp., and Meloidogyne spp. and their influence on soil microbial communities. Both Fusarium spp. and Phytophthora spp. were significantly reduced by the MB (30.74 mg kg-1, methyl iodide (MI: 45.58 mg kg-1, metham sodium (MS: 53.92 mg kg-1 treatments. MS exhibited comparable effectiveness to MB in controlling Meloidogyne spp. and total nematodes, followed by MI at the tested rate. By contrast, sulfuryl fluoride (SF: 33.04 mg kg-1 and chloroform (CF: 23.68 mg kg-1 showed low efficacy in controlling Fusarium spp., Phytophthora spp., and Meloidogyne spp. MB, MI and MS significantly lowered the abundance of different microbial populations and microbial biomass in soil, whereas SF and CF had limited influence on them compared with the control. Diversity indices in Biolog studies decreased in response to fumigation, but no significant difference was found among treatments in PLFA studies. Principal component and cluster analyses of Biolog and PLFA data sets revealed that MB and MI treatments greatly influenced the soil microbial community functional and structural diversity compared with SF treatment. These results suggest that fumigants with high effectiveness in suppressing soil-borne disease could significantly influence soil microbial community.

The effects of soil amendments on heavy metal bioavailability in two contaminated Mediterranean soils

Energy Technology Data Exchange (ETDEWEB)

Walker, D.J.; Clemente, Rafael; Roig, Asuncion; Bernal, M.P

2003-04-01

The effects of organic amendments on metal bioavailability were not always related to their degree of humification. - Two heavy metal contaminated calcareous soils from the Mediterranean region of Spain were studied. One soil, from the province of Murcia, was characterised by very high total levels of Pb (1572 mg kg{sup -1}) and Zn (2602 mg kg{sup -1}), whilst the second, from Valencia, had elevated concentrations of Cu (72 mg kg{sup -1}) and Pb (190 mg kg{sup -1}). The effects of two contrasting organic amendments (fresh manure and mature compost) and the chelate ethylenediaminetetraacetic acid (EDTA) on soil fractionation of Cu, Fe, Mn, Pb and Zn, their uptake by plants and plant growth were determined. For Murcia soil, Brassica juncea (L.) Czern. was grown first, followed by radish (Raphanus sativus L.). For Valencia soil, Beta maritima L. was followed by radish. Bioavailability of metals was expressed in terms of concentrations extractable with 0.1 M CaCl{sub 2} or diethylenetriaminepentaacetic acid (DTPA). In the Murcia soil, heavy metal bioavailability was decreased more greatly by manure than by the highly-humified compost. EDTA (2 mmol kg{sup -1} soil) had only a limited effect on metal uptake by plants. The metal-solubilising effect of EDTA was shorter-lived in the less contaminated, more highly calcareous Valencia soil. When correlation coefficients were calculated for plant tissue and bioavailable metals, the clearest relationships were for Beta maritima and radish.

Arsenic contamination of soils and agricultural plants through irrigation water in Nepal

Energy Technology Data Exchange (ETDEWEB)

Dahal, B.M. [Institute of Soil Research, University of Natural Resources and Applied Life Sciences (BOKU), Peter Jordan Strasse 82, A-1190 Vienna (Austria); Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna (Austria); Environment and Public Health Organization (ENPHO), P.O. Box 4102, Kathmandu (Nepal); Fuerhacker, M. [Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna (Austria); Mentler, A. [Institute of Soil Research, University of Natural Resources and Applied Life Sciences (BOKU), Peter Jordan Strasse 82, A-1190 Vienna (Austria); Karki, K.B. [Soil Science Division, Nepal Agricultural Research Council, Khumaltar, Lalitpur (Nepal); Shrestha, R.R. [UN Habitat-Nepal, UN House, Pulchwok, P.O. Box 107, Kathmandu (Nepal); Blum, W.E.H. [Institute of Soil Research, University of Natural Resources and Applied Life Sciences (BOKU), Peter Jordan Strasse 82, A-1190 Vienna (Austria)], E-mail: winfried.blum@boku.ac.at

2008-09-15

This study monitored the influence of arsenic-contaminated irrigation water on alkaline soils and arsenic uptake in agricultural plants at field level. The arsenic concentrations in irrigation water ranges from <0.005 to 1.014 mg L{sup -1} where the arsenic concentrations in the soils were measured from 6.1 to 16.7 mg As kg{sup -1}. The arsenic content in different parts of plants are found in the order of roots > shoots > leaves > edible parts. The mean arsenic content of edible plant material (dry weight) were found in the order of onion leaves (0.55 mg As kg{sup -1}) > onion bulb (0.45 mg As kg{sup -1}) > cauliflower (0.33 mg As kg{sup -1}) > rice (0.18 mg As kg{sup -1}) > brinjal (0.09 mg As kg{sup -1}) > potato (<0.01 mg As kg{sup -1}). - The arsenic content in soil and plants is influenced by the degree of arsenic amount in irrigated water.

Facilitated transport of diuron and glyphosate in high copper vineyard soils.

Science.gov (United States)

Dousset, Sylvie; Jacobson, Astrid R; Dessogne, Jean-Baptiste; Guichard, Nathalie; Baveye, Philippe C; Andreux, Francis

2007-12-01

The fate of organic herbicides applied to agricultural fields may be affected by other soil amendments, such as copper applied as a fungicide. The effect of copper on the leaching of diuron and glyphosate through a granitic and a calcareous soil was studied in the laboratory using sieved-soil columns. Each soil was enriched with copper sulfate to obtain soil copper concentrations of 125, 250, 500, and 1000 mg kg(-1). Glyphosate leaching was influenced by soil pH and copper concentration, whereas diuron leaching was not. In the calcareous soil, glyphosate leaching decreased as copper levels increased from 17 mg kg(-1) (background) to 500 mg kg(-1). In the granitic soil, glyphosate leaching increased as copper levels increased from 34 mg kg(-1) (background) to 500 mg kg(-1). The shapes of the copper elution curves in presence of glyphosate were similar to shapes of the glyphosate curves, suggesting the formation of Cu-glyphosate complexes that leach through the soil. Soil copper concentration does not influence diuron leaching. In contrast, increasing copper concentrations reduces glyphosate leaching through calcareous soils, and conversely, increases glyphosate leaching through granitic soils. Our findings suggest that the risk of groundwater contamination by glyphosate increases in granitic soils with elevated copper concentrations.

Polycyclic aromatic hydrocarbons and pesticides in soil of Vojvodina

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Pucarević Mira M.

2004-01-01

Full Text Available The paper deals with several groups of compounds that represent the most frequent pollutants of soil in the world. The paper also reviews results of long-term studies conducted at the Institute of Field and Vegetable Crops in Novi Sad on the residues of pesticides and polycyclic aromatic hydrocarbons (PAHs in the soil of the Vojvodina Province. The analyzed samples have been found to contain residues of persistent pesticides and their metabolites lindane and its metabolites 6,20 μg/kg, alachlor 3,56 μg/kg, aldrin 2,3 μg/kg, heptachlor epoxide 0,99 μg/kg, chlordane 3,82 μg/kg, DDT and its metabolites 10,77 μg/kg, dieldrin 2,04 μg/kg, endrin 3,57 μg/kg and endrin aldehyde 1,36 μg/kg. Soil samples from Novi Sad municipality contained 53,69 μg/kg of DDT and its metabolites. The values of atrazine ranged from 0,0005 to 0,8 mg/kg. The values of PAHs were 6,64 mg/kg in industrial soil, 4,93 mg/kg in agricultural soil, and 4,55 mg/kg and 5,48 mg/kg in the Novi Sad municipality. The lowest value, 0.83 mg/kg, was found for nonagricultural/nonindustrial soils.

Accumulation of oil and grease in soils irrigated with greywater and their potential role in soil water repellency.

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Travis, Micheal J; Weisbrod, Noam; Gross, Amit

2008-05-01

The potential impact of oil and grease (O and G) to soils irrigated with greywater (GW) was investigated. Greywater streams were sampled and analyzed for O and G content, along with corresponding GW-irrigated soils. Untreated kitchen GW averaged 200 mg L(-1) O and G, over an order of magnitude more than other GW streams. GW-irrigated soils showed O and G accumulation of up to 200 mg kg(-l) within the first 20-cm of depth. To determine the potential effects of such O and G accumulation on water movement in soil, capillary rise and water drop penetration time (WDPT) experiments were conducted. The results showed up to 60% decrease in capillary rise when sand containing 250 mg kg(-1) O and G was used. Interestingly, no additional reduction in capillary rise was observed at concentrations above 250 mg kg(-1). WDPT was observed to increase linearly with increased O and G content, up to 1000 mg kg(-1). This work demonstrated that O and G in GW used for irrigation can accumulate in soil and may lead to a significant reduction in the soils ability to transmit water.

[Soil soluble organic matter, microbial biomass, and enzyme activities in forest plantations in degraded red soil region of Jiangxi Province, China].

Science.gov (United States)

Jiang, Yu-mei; Chen, Cheng-long; Xu, Zhi-hong; Liu, Yuan-qiu; Ouyang, Jing; Wang, Fang

2010-09-01

Taking the adjacent 18-year-old pure Pinus massoniana pure forest (I), P. massoniana, Liquidamber fomosana, and Schima superba mixed forest (II), S. superba pure forest (III), L. fomosana (IV) pure forest, and natural restoration fallow land (CK) in Taihe County of Jiangxi Province as test sites, a comparative study was made on their soil soluble organic carbon (SOC) and nitrogen (SON), soil microbial biomass C (MBC) and N (MBN), and soil urease and asparaginase activities. In 0-10 cm soil layer, the pool sizes of SOC, SON, MBC, and MBN at test sites ranged in 354-1007 mg x kg(-1), 24-73 mg x kg(-1), 203-488 mg x kg(-1), and 24-65 mg x kg(-1), and the soil urease and asparaginase activities were 95-133 mg x kg(-1) x d(-1) and 58-113 mg x kg(-1) x d(-1), respectively. There were significant differences in the pool sizes of SOC, SON, MBC, and MBN and the asparaginase activity among the test sites, but no significant difference was observed in the urease activity. The pool sizes of SOC and SON were in the order of IV > CK > III > I > II, those of MBC and MBN were in the order of CK > IV > III > I > II, and asparaginase activity followed the order of IV > CK > III > II > I. With the increase of soil depth, the pool sizes of SOC, SON, MBC, and MBN and the activities of soil asparaginase and urease decreased. In 0-20 cm soil layer, the SOC, SON, MBC, MBN, total C, and total N were highly correlated with each other, soil asparaginase activity was highly correlated with SOC, SON, TSN, total C, total N, MBC, and MBN, and soil urease activity was highly correlated with SON, TSN, total C, MBC and MBN.

Arsenic contamination of soils and agricultural plants through irrigation water in Nepal

International Nuclear Information System (INIS)

Dahal, B.M.; Fuerhacker, M.; Mentler, A.; Karki, K.B.; Shrestha, R.R.; Blum, W.E.H.

2008-01-01

This study monitored the influence of arsenic-contaminated irrigation water on alkaline soils and arsenic uptake in agricultural plants at field level. The arsenic concentrations in irrigation water ranges from -1 where the arsenic concentrations in the soils were measured from 6.1 to 16.7 mg As kg -1 . The arsenic content in different parts of plants are found in the order of roots > shoots > leaves > edible parts. The mean arsenic content of edible plant material (dry weight) were found in the order of onion leaves (0.55 mg As kg -1 ) > onion bulb (0.45 mg As kg -1 ) > cauliflower (0.33 mg As kg -1 ) > rice (0.18 mg As kg -1 ) > brinjal (0.09 mg As kg -1 ) > potato ( -1 ). - The arsenic content in soil and plants is influenced by the degree of arsenic amount in irrigated water

Effect of heavy metals on pH buffering capacity and solubility of Ca, Mg, K, and P in non-spiked and heavy metal-spiked soils.

Science.gov (United States)

Najafi, Sarvenaz; Jalali, Mohsen

2016-06-01

In many parts of the world, soil acidification and heavy metal contamination has become a serious concern due to the adverse effects on chemical properties of soil and crop yield. The aim of this study was to investigate the effect of pH (in the range of 1 to 3 units above and below the native pH of soils) on calcium (Ca), magnesium (Mg), potassium (K), and phosphorus (P) solubility in non-spiked and heavy metal-spiked soil samples. Spiked samples were prepared by cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn) as chloride salts and incubating soils for 40 days. The pH buffering capacity (pHBC) of each sample was determined by plotting the amount of H(+) or OH(-) added (mmol kg(-1)) versus the related pH value. The pHBC of soils ranged from 47.1 to 1302.5 mmol kg(-1) for non-spiked samples and from 45.0 to 1187.4 mmol kg(-1) for spiked soil samples. The pHBC values were higher in soil 2 (non-spiked and spiked) which had higher calcium carbonate content. The results indicated the presence of heavy metals in soils generally decreased the solution pH and pHBC values in spiked samples. In general, solubility of Ca, Mg, and K decreased with increasing equilibrium pH of non-spiked and spiked soil samples. In the case of P, increasing the pH to about 7, decreased the solubility in all soils but further increase of pH from 7, enhanced P solubility. The solubility trends and values for Ca, Mg, and K did not differed significantly in non-spiked and spiked samples. But in the case of P, a reduction in solubility was observed in heavy metal-spiked soils. The information obtained in this study can be useful to make better estimation of the effects of soil pollutants on anion and cation solubility from agricultural and environmental viewpoints.

Exposure and bioavailability of arsenic in contaminated soils from the La Parrilla mine, Spain

Science.gov (United States)

Anawar, H. M.; Garcia-Sanchez, A.; Murciego, A.; Buyolo, T.

2006-05-01

Arsenic derived from mining activity may contaminate water, soil and plant ecosystems resulting in human health and ecotoxicological risks. In this study, exposure assessment of arsenic (As) in soil, spoil, pondwater and plants collected from the areas contaminated by mine tailings and spoils in and around the La Parrilla mine, Caceres province, Spain, was carried out using AAS method. Water solubility, bioavailability and soil-plant transfer coefficients of As and phytoremediation potential of plants were determined. Arsenic concentrations varied from 148 to 2,540 mg/kg in soils of site 1 and from 610 to 1,285 mg/kg in site 2 exceeding the guideline limit for agricultural soil (50 mg/kg). Arsenic concentrations in pond waters varied from 8.8 to 101.4 μg/l. High concentrations of water-soluble As in the soils that ranged from 0.10 to 4.71 mg/kg in site 1 and from 0.46 to 4.75 mg/kg in site 2 exceeded the maximum permitted level of water-soluble As (0.04 mg/kg) in agricultural soils. Arsenic concentrations varied from 0.8 to 149.5 mg/kg dry wt in the plants of site 1 and from 2.0 to 10.0 mg/kg in the plants of site 2. Arsenic concentrations in plants increased in the approximate order: Retama sphaerocarpa phytoremediation of As contaminated soils.

Postoperative impairment of motor function at train-of-four ratio ≥0.9 cannot be improved by sugammadex (1 mg kg-1).

Science.gov (United States)

Baumüller, E; Schaller, S J; Chiquito Lama, Y; Frick, C G; Bauhofer, T; Eikermann, M; Fink, H; Blobner, M

2015-05-01

A train-of-four ratio (TOFR) ≥0.9 measured by quantitative neuromuscular monitoring is accepted as an indication of sufficient neuromuscular recovery for extubation, even though many postsynaptic acetylcholine receptors may still be inhibited. We investigated whether antagonism with sugammadex after spontaneous recovery to TOFR≥0.9 further improves muscle function or subjective well-being. Following recovery to TOFR≥0.9 and emergence from anaesthesia, 300 patients randomly received either sugammadex 1.0 mg kg(-1) or placebo. Fine motor function (Purdue Pegboard Test) and maximal voluntary grip strength were measured before and after surgery (before and after test drug administration). At discharge from the postanaesthesia care unit, well-being was assessed with numerical analogue scales and the Quality-of-Recovery Score 40 (QoR-40). Patients' fine motor function [6 (sd 4) vs 15 (3) pegs (30 s)(-1), Psugammadex or placebo, motor function was significantly improved in both groups but did not reach the preoperative level. There was no difference between groups at any time. Global well-being was unaffected (QoR-40: placebo, 174 vs 185; sugammadex, 175 vs 186, P>0.05). Antagonizing rocuronium at TOF≥0.9 with sugammadex 1.0 mg kg(-) (1) did not improve patients' motor function or well-being when compared with placebo. Our data support the view that TOFR≥0.9 measured by electromyography signifies sufficient recovery of neuromuscular function. The trial is registered at ClinicalTrials.gov (NCT01101139). © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Distribution and mobility of mercury in soils of a gold mining region, Cuyuni river basin, Venezuela.

Science.gov (United States)

Santos-Francés, F; García-Sánchez, A; Alonso-Rojo, P; Contreras, F; Adams, M

2011-04-01

An extensive and remote gold mining region located in the East of Venezuela has been studied with the aim of assessing the distribution and mobility of mercury in soil and the level of Hg pollution at artisanal gold mining sites. To do so, soils and pond sediments were sampled at sites not subject to anthropological influence, as well as in areas affected by gold mining activities. Total Hg in regionally distributed soils ranged between 0.02 mg kg(-1) and 0.40 mg kg(-1), with a median value of 0.11 mg kg(-1), which is slightly higher than soil Hg worldwide, possibly indicating long-term atmospheric input or more recent local atmospheric input, in addition to minor lithogenic sources. A reference Hg concentration of 0.33 mg kg(-1) is proposed for the detection of mining affected soils in this region. Critical total Hg concentrations were found in the surrounding soils of pollutant sources, such as milling-amalgamation sites, where soil Hg contents ranged from 0.16 mg kg(-1) to 542 mg kg(-1) with an average of 26.89 mg kg(-1), which also showed high levels of elemental Hg, but quite low soluble+exchangeable Hg fraction (0.02-4.90 mg kg(-1)), suggesting low Hg soil mobility and bioavailability, as confirmed by soil column leaching tests. The vertical distribution of Hg through the soil profiles, as well as variations in soil Hg contents with distance from the pollution source, and Hg in pond mining sediments were also analysed. Copyright © 2010 Elsevier Ltd. All rights reserved.

Final report of AFRIMETS.M.M-S6: supplementary comparison of 100 mg, 100 g 500 g, 1 kg and 5 kg stainless steel mass standards

Science.gov (United States)

Mautjana, R. T.; Molefe, P. T.; Mayindu, N. F.; Armah, M. N.; Ramasawmy, V.; Albasini, G. L.; Matali, S.; Richmond, H.; Rusimbi, V.; Kiwanuka, J.; Mutale, D. M.; Mutsimba, F.

2018-01-01

This report summarizes the results of AFRIMETS.M.M-S6 mass standards comparison conducted between eleven participating laboratories/countries. Two sets of five weights with nominal values 100 mg, 100 g, 500 g, 1 kg and 5 kg were used as the traveling standards. These nominal values were decided from the needs of participating laboratories submitted to the pilot laboratory through a questionnaire and agreed upon by all participants. The traveling standards were hand carried between laboratories starting from February 2014 and were received from the last participants in October 2014. The programme was coordinated by National Metrology Institute of South Africa (NMISA), who provided the travelling standards and reference values for the comparison. The corrections to the BIPM as-maintained mass unit [5] have insignificant influence on the results of this comparison. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Concentrations in plasma, epithelial lining fluid, alveolar macrophages and bronchial mucosa after a single intravenous dose of 1.6 mg/kg of iclaprim (AR-100) in healthy men.

Science.gov (United States)

Andrews, J; Honeybourne, D; Ashby, J; Jevons, G; Fraise, A; Fry, P; Warrington, S; Hawser, S; Wise, R

2007-09-01

A validated microbiological assay was used to measure concentrations of iclaprim (AR-100) in plasma, bronchial mucosa (BM), alveolar macrophages (AM) and epithelial lining fluid (ELF) after a single 1.6 mg/kg intravenous 60 min iv infusion of iclaprim. Male volunteers were randomly allocated to three nominal sampling time intervals 1-2 h (Group A), 3-4 h (Group B) and 5.5-7.0 h (Group C) after the start of the drug infusion. Mean iclaprim concentrations in plasma, BM, AM and ELF, respectively, were for Group A 0.59 mg/L (SD 0.18), 0.51 mg/kg (SD 0.17), 24.51 mg/L (SD 21.22) and 12.61 mg/L (SD 7.33); Group B 0.24 mg/L (SD 0.05), 0.35 mg/kg (SD 0.17), 7.16 mg/L (SD 1.91) and 6.38 mg/L (SD 5.17); and Group C 0.14 mg/L (SD 0.05), no detectable level in BM, 5.28 mg/L (SD 2.30) and 2.66 mg/L (SD 2.08). Iclaprim concentrations in ELF and AM exceeded the MIC(90) for penicillin-susceptible Streptococcus pneumoniae (MIC90 0.06 mg/L), penicillin-intermediate S. pneumoniae (MIC90 2 mg/L), penicillin-resistant S. pneumoniae (MIC90 4 mg/L) for 7, 7 and 4 h, respectively, and Chlamydia pneumoniae (MIC90 0.5 mg/L) for 7 h. Mean iclaprim concentrations in ELF exceeded the MIC90 for Haemophilus influenzae (MIC90 4 mg/L) and Moraxella catarrhalis (MIC90 8 mg/L) for up to 4 and 2 h, respectively; in AM the MIC90 was exceeded for up to 7 h. Furthermore, the MIC90 for methicillin-resistant Staphylococcus aureus of 0.12 mg/L was exceeded at all sites for up to 7 h. These data suggest that iclaprim reaches lung concentrations that should be effective in the treatment of community-acquired pneumonia.

Transformation products of 1,1-dimethylhydrazine and their distribution in soils of fall places of rocket carriers in Central Kazakhstan

International Nuclear Information System (INIS)

Kenessov, Bulat; Alimzhanova, Mereke; Sailaukhanuly, Yerbolat; Baimatova, Nassiba; Abilev, Madi; Batyrbekova, Svetlana; Carlsen, Lars; Tulegenov, Akyl; Nauryzbayev, Mikhail

2012-01-01

In our research, three fall places of first stages of Proton rockets have been studied for the presence and distribution of transformation products of 1,1-dimethylhydrazine (1,1-DMH). Results of identification of transformation products of 1,1-DMH in real soil samples polluted due to rocket fuel spills allowed to detect 18 earlier unknown metabolites of 1,1-DMH being formed only under field conditions. According to the results of quantitative analyses, maximum concentrations of 1-methyl-1H-1,2,4-triazole made up 57.3, 44.9 and 13.3 mg kg −1 , of 1-ethyl-1H-1,2,4-triazole — 5.45, 3.66 and 0.66 mg kg −1 , of 1,3-dimethyl-1H-1,2,4-triazole - 24.0, 17.8 and 4.9 mg kg −1 in fall places 1, 2 and 3, respectively. 4-Methyl-4H-1,2,4-triazole was detected only in fall places 2 and 3 where its maximum concentrations made up 4.2 and 0.66 mg kg −1 , respectively. The pollution of soils with transformation products of 1,1-DMH was only detected in epicenters of fall places having a diameter of 8 to10 m where rocket boosters landed. The results of a detailed study of distribution of 1,1-DMH transformation products along the soil profile indicate that transformation products can migrate down to the depth of 120 cm, The highest concentrations of 1,1-DMH transformation products were detected, as a rule, at the depth 20 to 60 cm. However, this index can vary depending on the compound, humidity and physical properties of soil, landscape features and other conditions. In the surface layer, as a rule, only semi-volatile products of transformation were detected which was caused by fast evaporation and biodegradation of volatile metabolites. - Highlights: ► We study metabolites of 1,1-dimethylhydrazine and their distribution in soils. ► Fifty four metabolites can be formed in soils polluted with 1,1-dimethylhydrazine. ► Metabolites are detected in the epicenter having diameter of about 10 m. ► Metabolites can migrate down to the depth of 120 cm. ► Volatile metabolites

Transformation products of 1,1-dimethylhydrazine and their distribution in soils of fall places of rocket carriers in Central Kazakhstan

Energy Technology Data Exchange (ETDEWEB)

Kenessov, Bulat, E-mail: bkenesov@gmail.com [Center of Physical Chemical Methods of Research and Analysis, al-Farabi Kazakh National University, 96A Tole Bi st., Almaty, 050012 (Kazakhstan); Alimzhanova, Mereke; Sailaukhanuly, Yerbolat; Baimatova, Nassiba; Abilev, Madi; Batyrbekova, Svetlana [Center of Physical Chemical Methods of Research and Analysis, al-Farabi Kazakh National University, 96A Tole Bi st., Almaty, 050012 (Kazakhstan); Carlsen, Lars [Awareness Center, Linkopingvej 35, Trekroner, DK-4000 Roskilde (Denmark); Department of Chemical Engineering, Kazakh-British Technical University, 59 Tole Bi st., Almaty, 050000 (Kazakhstan); Tulegenov, Akyl; Nauryzbayev, Mikhail [Center of Physical Chemical Methods of Research and Analysis, al-Farabi Kazakh National University, 96A Tole Bi st., Almaty, 050012 (Kazakhstan)

2012-06-15

In our research, three fall places of first stages of Proton rockets have been studied for the presence and distribution of transformation products of 1,1-dimethylhydrazine (1,1-DMH). Results of identification of transformation products of 1,1-DMH in real soil samples polluted due to rocket fuel spills allowed to detect 18 earlier unknown metabolites of 1,1-DMH being formed only under field conditions. According to the results of quantitative analyses, maximum concentrations of 1-methyl-1H-1,2,4-triazole made up 57.3, 44.9 and 13.3 mg kg{sup -1}, of 1-ethyl-1H-1,2,4-triazole - 5.45, 3.66 and 0.66 mg kg{sup -1}, of 1,3-dimethyl-1H-1,2,4-triazole - 24.0, 17.8 and 4.9 mg kg{sup -1} in fall places 1, 2 and 3, respectively. 4-Methyl-4H-1,2,4-triazole was detected only in fall places 2 and 3 where its maximum concentrations made up 4.2 and 0.66 mg kg{sup -1}, respectively. The pollution of soils with transformation products of 1,1-DMH was only detected in epicenters of fall places having a diameter of 8 to10 m where rocket boosters landed. The results of a detailed study of distribution of 1,1-DMH transformation products along the soil profile indicate that transformation products can migrate down to the depth of 120 cm, The highest concentrations of 1,1-DMH transformation products were detected, as a rule, at the depth 20 to 60 cm. However, this index can vary depending on the compound, humidity and physical properties of soil, landscape features and other conditions. In the surface layer, as a rule, only semi-volatile products of transformation were detected which was caused by fast evaporation and biodegradation of volatile metabolites. - Highlights: Black-Right-Pointing-Pointer We study metabolites of 1,1-dimethylhydrazine and their distribution in soils. Black-Right-Pointing-Pointer Fifty four metabolites can be formed in soils polluted with 1,1-dimethylhydrazine. Black-Right-Pointing-Pointer Metabolites are detected in the epicenter having diameter of about 10 m

Effects of uranium on soil microbial biomass carbon, enzymes, plant biomass and microbial diversity in yellow soils

International Nuclear Information System (INIS)

Yan, X.; Zhang, Y.; Luo, X.; Yu, L.

2016-01-01

We conducted an experiment to investigate the effects of uranium (U) on soil microbial biomass carbon (MBC), enzymes, plant biomass and microbial diversity in yellow soils under three concentrations: 0 mg kg"-"1 (T1, control), 30 mg kg"-"1 (T2) and 60 mg kg"-"1 (T3). Under each treatment, elevated U did not reduce soil MBC or plant biomass, but inhibited the activity of the soil enzymes urease (UR), dehydrogenase (DH) and phosphatase (PHO). The microbial diversity was different, with eight dominant phyla in T1 and six in T2 and T3. Furthermore, Proteobacteria and material X were both detected in each treatment site (T1, T2 and T3). Pseudomonas sp. was the dominant strain, followed by Acidiphilium sp. This initial study provided valuable data for further research toward a better understanding of U contamination in yellow soils in China. (authors)

Cadmium accumulation characteristics of low-cadmium rice (Oryza sativa L.) line and F1 hybrids grown in cadmium-contaminated soils.

Science.gov (United States)

Li, Kun; Yu, Haiying; Li, Tingxuan; Chen, Guangdeng; Huang, Fu

2017-07-01

Cadmium (Cd) pollution has threatened severely to food safety and human health. A pot experiment and a field experiment were conducted to investigate the difference of Cd accumulation between rice (Oryza sativa L.) lines and F 1 hybrids in Cd-contaminated soils. The adverse effect on biomass of rice lines was greater than that of F 1 hybrids under Cd treatments in the pot experiment. The variations of Cd concentration among rice cultivars in different organs were smaller in stem and leaf, but larger in root and ear. Average proportion of Cd in root of F 1 hybrids was 1.39, 1.39, and 1.16 times higher than those of rice lines at the treatment of 1, 2, and 4 mg Cd kg -1 soil, respectively. Cd concentrations in ear of F 1 hybrids were significantly lower than rice lines with the reduction from 29.24 to 50.59%. Cd concentrations in brown rice of all F 1 hybrids were less than 0.2 mg kg -1 at 1 mg Cd kg -1 soil, in which Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be screened out as cadmium-safe cultivars (CSCs) for being safe even at 2 mg Cd kg -1 soil. C268A/YaHui2816 showed the lowest Cd concentration in root among F 1 hybrids, while Lu98A/YaHui2816 and 5406A/YaHui2816 showed lower capability of Cd translocation from root to shoot under Cd exposure, which eventually caused the lower Cd accumulation in brown rice. The lower level of Cd translocation contributed to reducing the accumulation of Cd in brown rice had been validated by the field experiment. Thus, Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be considered as potential CSCs to cultivate in Cd-contaminated soils (<2 mg Cd kg -1 soil).

Heavy metal (Cu, Zn, Cd and Pb) partitioning and bioaccessibility in uncontaminated and long-term contaminated soils

International Nuclear Information System (INIS)

Lamb, Dane T.; Ming Hui; Megharaj, Mallavarapu; Naidu, Ravi

2009-01-01

We investigated the pore-water content and speciation of copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) in a range of uncontaminated and long-term contaminated soils in order to establish their potential bioaccessibility to soil biota, plants and humans. Among the samples, soil pH (0.01 M CaCl 2 ) ranged from 4.9 to 8.2. The total metal content of the uncontaminated soils ranged from 3.8 to 93.8 mg Cu kg -1 , 10.3 to 95 mg kg -1 Zn, 0.1 to 1.8 mg Cd kg -1 and 5.2 to 183 mg kg -1 Pb, while metal content in the contaminated soils ranged from 104 to 6841 mg Cu kg -1 , 312 to 39,000 mg kg -1 Zn, 6 to 302 mg Cd kg -1 and 609 to 12,000 mg kg -1 Pb. Our analysis of pore-water found the Cu concentrations to be much higher in contaminated soils than in uncontaminated soils, with the distribution coefficients (K d ) correlating significantly with the log of dissolved organic carbon concentrations. Despite the high total metal content of the contaminated soil, Zn, Cd and Pb were not generally found at elevated levels in the pore-water with the exception of a single contaminated soil. A long period of ageing and soil weathering may have led to a substantial reduction in heavy metal concentrations in the pore-water of contaminated soils. On the other hand, Pb bioaccessibility was found to be comparatively high in Pb contaminated soils, where it tended to exceed the total Pb values by more than 80%. We conclude that, despite the extensive ageing of some contaminated soils, the bioaccessibility of Pb remains relatively high.

Heavy metal (Cu, Zn, Cd and Pb) partitioning and bioaccessibility in uncontaminated and long-term contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Lamb, Dane T.; Ming Hui; Megharaj, Mallavarapu [Centre for Environmental Risk Assessment and Remediation, Building X, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), P.O. Box 486, Salisbury, SA 5106 (Australia); Naidu, Ravi, E-mail: ravi.naidu@crccare.com [Centre for Environmental Risk Assessment and Remediation, Building X, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), P.O. Box 486, Salisbury, SA 5106 (Australia)

2009-11-15

We investigated the pore-water content and speciation of copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) in a range of uncontaminated and long-term contaminated soils in order to establish their potential bioaccessibility to soil biota, plants and humans. Among the samples, soil pH (0.01 M CaCl{sub 2}) ranged from 4.9 to 8.2. The total metal content of the uncontaminated soils ranged from 3.8 to 93.8 mg Cu kg{sup -1}, 10.3 to 95 mg kg{sup -1} Zn, 0.1 to 1.8 mg Cd kg{sup -1} and 5.2 to 183 mg kg{sup -1} Pb, while metal content in the contaminated soils ranged from 104 to 6841 mg Cu kg{sup -1}, 312 to 39,000 mg kg{sup -1} Zn, 6 to 302 mg Cd kg{sup -1} and 609 to 12,000 mg kg{sup -1} Pb. Our analysis of pore-water found the Cu concentrations to be much higher in contaminated soils than in uncontaminated soils, with the distribution coefficients (K{sub d}) correlating significantly with the log of dissolved organic carbon concentrations. Despite the high total metal content of the contaminated soil, Zn, Cd and Pb were not generally found at elevated levels in the pore-water with the exception of a single contaminated soil. A long period of ageing and soil weathering may have led to a substantial reduction in heavy metal concentrations in the pore-water of contaminated soils. On the other hand, Pb bioaccessibility was found to be comparatively high in Pb contaminated soils, where it tended to exceed the total Pb values by more than 80%. We conclude that, despite the extensive ageing of some contaminated soils, the bioaccessibility of Pb remains relatively high.

Analysis on Cu and Zn Concentrations in Agricultural Soils of Ili District, Xinjiang Autonomous Region, China

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YANG Jing-na

2015-02-01

Full Text Available The aim of this work is mainly to investigate the contents of copper(Cuand zinc(Znin agricultural soils to provide basic infor-mation for the establishment of green and organic production base in Ili District, Xinjiang Autonomous Region. 600 topsoil samples of the a-gricultural land were collected from eight counties of Ili District, and the contents of Cu and Zn were determined by AAS after microwave di-gestion. The statistics analysis showed that the mean contents of Cu and Zn in the agricultural soils of Ili District were 28.68 mg·kg-1 and 83.17 mg·kg-1, respectively. The concentrations of Cu in the agricultural soils of Ili District ranged from 11.07 mg·kg-1 to 59.90 mg·kg-1, 85% of which ranged from 20 mg·kg-1 to 40 mg·kg-1; and the concentrations of Zn in the agricultural soils of Ili District ranged from 39.58 mg·kg-1 to 160.40 mg·kg-1, 90%of which ranged from 60 mg·kg-1 to 110 mg·kg-1. Furthermore, compared the Cu and Zn contents of the tested soils among the eight counties, Cu contents in Tekes County were higher than other counties, while Zn contents showed little difference. The con-tents of Cu and Zn in the tested soils were all below the threshold values that were established in the national environmental quality standard for soils(secondary standards, GB 15618-1995, but about 7% and 21% were higher than the Cu and Zn background values of soil in Ili District, respectively. Furthermore, the concentrations of Cu and Zn in soils of Ili District accord with the environmental requirements for or-ganic and green production base regulated by national standard of organic products(GB/T 19630-2011and industrial standard of green food(NY/T 391-2013.

Influence of soil properties and phosphate addition on arsenic uptake from polluted soils by velvetgrass (Holcus lanatus).

Science.gov (United States)

Lewińska, K; Karczewska, A

2013-01-01

Four kinds of soil material were used in a pot experiment with velvetgrass (Holcus lanatus). Two unpolluted soils: sand (S) and loam (L) were spiked with sodium arsenite (As II) and arsenate (As V), to obtain total arsenic (As) concentrations of 500 mg As kg(-1). Two other soils (ZS I, ZS III), containing 3320 and 5350 mg As kg(-1), were collected from Zloty Stok where gold and arsenic ores were mined and processed for several centuries. The effects of phosphate addition on plants growth and As uptake were investigated. Phosphate was applied to soils in the form of NH4H2PO4 at the rate 0.2 g P/kg. Average concentrations of arsenic in the shoots of velvetgrass grown in spiked soils S and L without P amendment were in the range 18-210 mg As kg(-1) d.wt., whereas those in plants grown on ZS I and ZS II soils were considerably lower, and varied in the range 11-52 mg As kg(-1) d.wt. The addition of phosphate caused a significant increase in plant biomass and therefore the total amounts of As taken up by plants, however, the differences in As concentrations in the shoots of velvetgrass amended and non-amended with phosphate were not statistically significant.

Is soil dressing a way once and for all in remediation of arsenic contaminated soils? A case study of arsenic re-accumulation in soils remediated by soil dressing in Hunan Province, China.

Science.gov (United States)

Su, Shiming; Bai, Lingyu; Wei, Caibing; Gao, Xiang; Zhang, Tuo; Wang, Yanan; Li, Lianfang; Wang, Jinjin; Wu, Cuixia; Zeng, Xibai

2015-07-01

The investigation of arsenic (As) re-accumulation in an area previously remediated by soil dressing will help in sustainable controlling the risks of As to local ecosystems and should influence management decisions about remediation strategies. In this study, As content in an area remediated by soil dressing and the possible As accumulation risk in agricultural products were investigated. The results indicated that after 7 years of agricultural activities, the average As content (24.6 mg kg(-1)) in surface soil of the investigated area increased by 83.6% compared with that (13.4 mg kg(-1)) in clean soil. Of the surface soil samples (n = 88), 21.6% had As levels that exceeded the limits of the Environmental Quality Standard for Soils of China (GB 15618-1995) and 98.9% of the surface soil samples with As contents exceeding that in clean soil was observed. Soil dressing might be not a remediation method once and for all in some contaminated areas, even though no significant difference in available As content was found between clean (0.18 mg kg(-1)) and surface (0.22 mg kg(-1)) soils. The foreign As in surface soil of the investigated area mainly specifically sorbed with soil colloid or associated with hydrous oxides of Fe and Al, or existed in residual fraction. The upward movement of contaminated soil from the deeper layers and the atmospheric deposition of slag particles might be responsible for the re-accumulation of As in the investigated area. Decreases in soil pH in the investigated soils and the fact that no plant samples had As levels exceeding the limits of the National Food Safety Standards for Contaminants of China (GB 2762-2012) were also observed.

Survival, Pb-uptake and behaviour of three species of earthworm in Pb treated soils determined using an OECD-style toxicity test and a soil avoidance test

International Nuclear Information System (INIS)

Langdon, Caroline J.; Hodson, Mark E.; Arnold, Rebecca E.; Black, Stuart

2005-01-01

Mature (clitellate) Eisenia andrei Bouche (ultra epigeic), Lumbricus rubellus Hoffmeister (epigeic), and Aporrectodea caliginosa (Savigny) (endogeic) earthworms were placed in soils treated with Pb(NO 3 ) 2 to have concentrations in the range 1000 to 10 000 mg Pb kg -1 . After 28 days LC50 -95%confidencelimit +95%confidencelimit values were E. andrei5824 -361 +898 mg Pb kg -1 , L. rubellus2867 -193 +145 mg Pb kg -1 and A. caliginosa2747 -304 +239 mg Pb kg -1 and EC50s for weight change were E. andrei2841 -68 +150 mg Pb kg -1 , L. rubellus1303 -201 +240 mg Pb kg -1 and A. caliginosa1208 -206 +212 mg Pb kg -1 . At any given soil Pb concentration, Pb tissue concentrations after 28 days were the same for all three earthworm species. In a soil avoidance test there was no difference between the behaviour of the different species. The lower sensitivity to Pb exhibited by E. andrei is most likely due to physiological adaptations associated with the modes of life of the earthworms, and could have serious implications for the use of this earthworm as the species of choice in standard toxicological testing.

Effects of Bio-char on Soil Microbes in Herbicide Residual Soils

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WANG Gen-lin

2015-10-01

Full Text Available Effects of biological carbon (bio-char on soil microbial community were studied by pot experiments simulating long residual herbicide residues in soil environment, which clarifed the improvement of biochar and its structural properties on soil microenvironment. The results showed that fungi and actinomycetes had the same effect tendency within 0~0.72 mg·kg-1 in clomazone residue which increased the role of stimulation with crop growth process prolonged, especially in high residue treatment, but strong inhibitory effect on bacteria community was occured early which returned to normal until sugar beet growth to fiftieth day. Soil fungi community decreased with bio-char adding, but had no significant difference with the control. When clomazone residue in soil was below 0.24 mg·kg-1, soil actinomycetes community was higher than control without bio-char, bacteria increased first and then reduced after adding carbon as below 0.12 mg·kg-1. Biochar was ‘deep hole’ structure containing C, O, S and other elements. The results showed that a certain concentration clomazone residue in soil would stimulate soil fungi and actinomycetes to grow. After adding the biochar, the inhibition effect of high herbicides residual on bacterial would be alleviated.

Phytoremediation of soil contaminated with cadmium, copper and polychlorinated biphenyls.

Science.gov (United States)

Wu, Longhua; Li, Zhu; Han, Cunliang; Liu, Ling; Teng, Ying; Sun, Xianghui; Pan, Cheng; Huang, Yujuan; Luo, Yongming; Christie, Peter

2012-07-01

A pot experiment and afield trial were conducted to study the remediation of an aged field soil contaminated with cadmium, copper and polychlorinated biphenyls (PCBs) (7.67 +/- 0.51 mg kg(-1) Cd, 369 +/- 1 mg kg(-1) Cu in pot experiment; 8.46 +/- 0.31 mg kg(-1) Cd, 468 +/- 7 mg kg(-1) Cu, 323 +/- 12 microg kg(-1) PCBs for field experiment) under different cropping patterns. In the pot experiment Sedum plumbizincicola showed pronounced Cd phytoextraction. After two periods (14 months) of cropping the Cd removal rates in these two treatments were 52.2 +/- 12.0 and 56.1 +/- 9.1%, respectively. Total soil PCBs in unplanted control pots decreased from 323 +/- 11 to 49.3 +/- 6.6 microg kg(-1), but with no significant difference between treatments. The field microcosm experiment intercropping of three plant species reduced the yield of S. plumbizincicola, with a consequent decrease in soil Cd removal. S. plumbizincicola intercropped with E. splendens had the highest shoot Cd uptake (18.5 +/- 1.8 mg pot(-1)) after 6 months planting followed by intercropping with M. sativa (15.9 +/- 1.9 mg pot(-1)). Liming with S. plumbizincicola intercropped with M. sativa significantly promoted soil PCB degradation by 25.2%. Thus, adjustment of soil pH to 5.56 combined with intercropping with S. plumbizincicola and M. sativagave high removal rates of Cd, Cu, and PCBs.

Soil Fertility Assessment and Mapping of Agricultural Research Station, Jaubari, Illam, Nepal

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Dinesh Khadka

2017-08-01

Full Text Available Soil fertility evaluation is a prerequisite factor for sustainable planning of a particular region. Considering this, a study was conducted to determine the soil fertility status of the Agricultural Research Station, Jaubari, Illam, Nepal. In total, 78 soil samples were collected using soil sampling auger randomly from a depth of 0-20 cm. The texture, pH, OM, N, P2O5, K2O, Ca, Mg, S, B, Fe, Zn, Cu and Mn status of the samples were analyzed in the laboratory of Soil Science Division, Khumaltar by following standard analytical methods. The soil fertility maps of the observed parameters were prepared through Arc-GIS 10.1 software. The observed data revealed that soil was brown (10YR 4/3, dark grayish brown (10YR 4/2, dark yellowish brown (10YR 4/4 and yellowish brown (10YR 5/6 in colour, and the structure was granular. Similarly, the sand, silt and clay content were 53.84±1.06%, 34.34±0.83% and 11.82±0.47%, respectively and were indicated as sandy loam and loam in texture. The soil was very acidic (pH 3.85±0.04, and very low in available boron (0.26±0.06mg/kg and available sulphur (0.59±0.15mg/kg. The available calcium (188.7±31.30mg/kg, available magnesium (50.98±5.0mg/kg and available manganese (5.16±0.90mg/kg were low. Likewise, available potassium (110.91±7.30mg/kg, available zinc (1.19±0.31mg/kg and available copper (0.95±0.05mg/kg content were medium. Similarly, organic matter (7.88±0.32%, total nitrogen (0.27±0.01% and available phosphorus (36.53±5.66mg/kg were high, and available iron (39.5±2.17 mg/kg was very high.  International Journal of EnvironmentVolume-6, Issue-3, Jun-Aug 2017, page: 46-70

Zinc transformations in neutral soil and zinc efficiency in maize fertilization.

Science.gov (United States)

Alvarez, Jose M; Gonzalez, Demetrio

2006-12-13

The effect of six Zn sources (Zn-phenolate, Zn-EDDHA, Zn-EDTA, Zn-lignosulfonate, Zn-polyflavonoid, and Zn-glucoheptonate) was studied by applying different Zn levels to a representative Calcic Haploxeralf neutral soil (the predominant clay is montmorillonite) in incubation and greenhouse experiments. Zinc soil behavior was evaluated by sequential DTPA and Mehlich-3 extraction procedures. In the incubation experiment, the highest percentage recovery values of Zn applied to soil occurred in the water-soluble plus exchangeable fraction (29%) in fertilization with 20 mg of Zn kg(-1) of Zn-EDTA fertilizer. In the greenhouse experiment with maize (Zea mays L.), a comparison of different Zn carriers showed that the application of six fertilizers did not significantly increase the plant dry matter yield among fertilizer treatments. The highest yield occurred when 20 mg of Zn kg(-1) was applied as Zn-EDDHA fertilizer (79.4 g per pot). The relative effectiveness of the Zn sources in increasing Zn concentration in plants was in the following order: Zn-EDTA (20 mg kg(-1)) > Zn-EDDHA (20 mg kg(-1)) approximately Zn-EDTA (10 mg kg(-1)) > Zn-EDDHA (10 mg kg(-1)) approximately Zn-phenolate (both rates) approximately Zn-polyflavonoid (both rates) approximately Zn-lignosulfonate (both rates) approximately Zn-glucoheptonate (both rates) > untreated Zn. The highest amounts of Zn taken up by the plants occurred when Zn was applied as Zn-EDTA fertilizer (20 mg kg(-1), 7.44 mg of Zn per pot; 10 mg kg(-1) Zn rate, 3.93 mg of Zn per pot) and when Zn was applied as Zn-EDDHA fertilizer (20 mg kg(-1) Zn rate, 4.66 mg Zn per pot). After the maize crop was harvested, sufficient quantities of available Zn remained in the soil (DTPA- or Mehlich-3-extractable Zn) for another harvest.

Influencia del uso del suelo en su calidad ambiental en medio semiárido (Murcia SE España Soil environmental quality related to different soil uses in a semiarid zone (Murcia SE Spain

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J. A. Hernández

2010-01-01

Full Text Available La agricultura intensiva y las activida­des mineras se encuentran entre las prin­cipales fuentes de contaminación del sue-lo ocasionando con frecuencia la acumu­lación en el mismo de sales solubles, nu­trientes, metales pesados, etc., con la con­siguiente pérdida de calidad del mismo. Este trabajo plantea conocer la situación de los suelos de un área de Murcia (SE España bajo diferentes usos y parcial­mente afectada por residuos mineros. Los resultados apuntan a que los usos conside­rados, provocan una disminución de cali­dad del suelo. Así, hay una mayor presen­cia de sales solubles (Conductividad Eléc­trica: 3,3-1,9 dS m-1, NO3 (126,5-51,1 mg kg-1 y P asimilable (29,6-2,4 mg kg-1 en los suelos cultivados frente a los no cultivados. Además, gran parte de las muestras presentan niveles de metales pe­sados que superan, ampliamente en oca­siones, los valores de referencia maneja­dos habitualmente: Cd: 10,2 mg kg-1; Cu: 85,2 mg kg-1; Mn: 2307,8 mg kg-1; Pb: 6793,0 mg kg-1; Zn: 4610,0 mg kg-1Intensive agriculture and mining activi­ties are among the soil uses that cause soil contamination because of the accumula­tion of soluble salts, nutrients, heavy met­als, etc. and consequently a loss of soil quality. This study set out to assess the condition of some cultivated and unculti­vated soils in an area of Murcia (SE Spain, known to be partially affected by mine acid materials. The results confirm that the cited activities have lead to a loss of soil quality, limiting their future use. Higher soluble salt (Electrolytic Conduc­tivity: 3,3-1,9 dS m-1, NO3 (126,5-51,1 mg kg-1 and available P (29,6-2,4 mg kg­1 concentrations were measured in the cultivated soils. In addition, many of the soil samples studied presented high levels of heavy metals which exceeded the val­ues usually taken as reference values: Cd: 10,2 mg kg-1; Cu: 85,2 mg kg-1; Mn: 2307,8 mg kg-1; Pb: 6793,0 mg kg-1 and Zn: 4610,0 mg kg-1 .

[Selenium uptake and transport of rice under different Se-enriched natural soils].

Science.gov (United States)

Jiang, Chao-qiang; Shen, Jia; Zu, Chao-long

2015-03-01

In this study, a pot experiment was conducted with "Wandao 205" as test materials to investigate Se uptake and translocation in rice under different Se concentrations (0.5, 1.0, and 1.5 mg . kg-1). Results showed that there was no significant change in rice yield when Se concentration in soil was lower than 1.5 mg . kg-1. Significant linear correlations existed between Se concentration in soil and different rice plant tissues. Se concentration in rice plant followed the order of root > straw > grain. Se concentration in different rice grain fractions followed the order of bran > polished rice > hull. The root absorption index of Se was more than 1.86, suggest that the rice could absorpt Se from soil effectively. However, the transport and accumulation of Se in seeds from Se-enriched soil was relatively constant. The Se transport index in seeds was between 0.53 and 0.59. Soil Se concentration within the range of 0.5 to 1.0 mg . kg-1 could produce Se-enriched rice, which might be enough for human requirement of 60-80 µg . d-1 Se. However, polished rice at high-Se treatment (1.5 mg . kg-1) exceeded the maximum standard limit of Se (0.3 mg . kg-1) for cereals in China. These results suggested that we could produce Se-enriched rice under soil Se concentration in the range of 0.5 to 1.0 mg . kg-1 without spraying Se fertilizer, thus reducing the cost and avoiding soil and water pollution caused by exogenous Se.

Influence of flooding and metal immobilising soil amendments on availability of metals for willows and earthworms in calcareous dredged sediment-derived soils

Energy Technology Data Exchange (ETDEWEB)

Vandecasteele, Bart, E-mail: bart.vandecasteele@ilvo.vlaanderen.b [Institute for Agricultural and Fisheries Research (ILVO), Scientific Institute of the Flemish Government, Burg. Van Gansberghelaan 109, B-9820 Merelbeke (Belgium); Du Laing, Gijs [Ghent University, Department of Applied Analytical and Physical Chemistry, Coupure 653, B-9000 Ghent (Belgium); Lettens, Suzanna [Research Institute for Nature and Forest (INBO), Scientific Institute of the Flemish Government, Gaverstraat 4, B-9500 Geraardsbergen (Belgium); Jordaens, Kurt [Department of Biology, Evolutionary Biology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Tack, Filip M.G. [Ghent University, Department of Applied Analytical and Physical Chemistry, Coupure 653, B-9000 Ghent (Belgium)

2010-06-15

Soil amendments previously shown to be effective in reducing metal bioavailability and/or mobility in calcareous metal-polluted soils were tested on a calcareous dredged sediment-derived soil with 26 mg Cd/kg dry soil, 2200 mg Cr/kg dry soil, 220 mg Pb/kg dry soil, and 3000 mg Zn/kg dry soil. The amendments were 5% modified aluminosilicate (AS), 10% w/w lignin, 1% w/w diammonium phosphate (DAP, (NH{sub 4}){sub 2}HPO{sub 4}), 1% w/w MnO, and 5% w/w CaSO{sub 4}. In an additional treatment, the contaminated soil was submerged. Endpoints were metal uptake in Salix cinerea and Lumbricus terrestris, and effect on oxidation-reduction potential (ORP) in submerged soils. Results illustrated that the selected soil amendments were not effective in reducing ecological risk to vegetation or soil inhabiting invertebrates, as metal uptake in willows and earthworms did not significantly decrease following their application. Flooding the polluted soil resulted in metal uptake in S. cinerea comparable with concentrations for an uncontaminated soil. - Some soil amendments resulted in higher metal uptake by earthworms and willows than when the polluted soil was not amended but submersion of the polluted soil resulted in reduced Cd and Zn uptake in Salix cinerea.

Soil fungi for mycoremediation of arsenic pollution in agriculture soils.

Science.gov (United States)

Singh, M; Srivastava, P K; Verma, P C; Kharwar, R N; Singh, N; Tripathi, R D

2015-11-01

Soil arsenic (As) contamination of food-chains and public health can be mitigated through fungal bioremediation. To enumerate culturable soil fungi, soils were collected from the As-contaminated paddy fields (3-35 mg kg(-1) ) of the middle Indo-Gangetic Plains. Total 54 fungal strains were obtained and identified at their molecular level. All strains were tested for As tolerance (from 100 to 10,000 mg l(-1) arsenate). Fifteen fungal strains, tolerant to 10,000 mg l(-1) arsenate, were studied for As removal in-vivo for 21 days by cultivating them individually in potato dextrose broth enriched with 10 mg l(-1) As. The bioaccumulation of As in fungal biomass ranged from 0·023 to 0·259 g kg(-1). The biovolatilized As ranged from 0·23 to 6·4 mg kg(-1). Higher As bioaccumulation and biovolatilization observed in the seven fungal strains, Aspergillus oryzae FNBR_L35; Fusarium sp. FNBR_B7, FNBR_LK5 and FNBR_B3; Aspergillus nidulans FNBR_LK1; Rhizomucor variabilis sp. FNBR_B9; and Emericella sp. FNBR_BA5. These fungal strains were also tested and found suitable for significant plant growth promotion in the calendula, withania and oat plants in a greenhouse based pot experiment. These fungal strains can be used for As remediation in As-contaminated agricultural soils. © 2015 The Society for Applied Microbiology.

Combinational effects of sulfomethoxazole and copper on soil microbial community and function.

Science.gov (United States)

Liu, Aiju; Cao, Huansheng; Yang, Yan; Ma, Xiaoxuan; Liu, Xiao

2016-03-01

Sulfonamides and Cu are largely used feed additives in poultry farm. Subsequently, they are spread onto agricultural soils together with contaminated manure used as fertilizer. Both sulfonamides and Cu affect the soil microbial community. However, an interactive effect of sulfonamides and Cu on soil microorganisms is not well understood. Therefore, a short-time microcosm experiment was conducted to investigate the interaction of veterinary antibiotic sulfomethoxazole (SMX) and Cu on soil microbial structure composition and functions. To this end, selected concentrations of SMX (0, 5, and 50 mg kg(-1)) and Cu (0, 300, and 500 mg kg(-1)) were combined, respectively. Clear dose-dependent effects of SMX on microbial biomass and basal respiration were determined, and these effects were amplified in the presence of additional Cu. For activities of soil enzymes including β-glucosidase, urease, and protease, clear reducing effects were determined in soil samples containing 5 or 50 mg kg(-1) of SMX, and the interaction of SMX and Cu was significant, particularly in soil samples containing 50 mg kg(-1) SMX or 500 mg kg(-1) Cu. SMX amendments, particularly in combination with Cu, significantly reduced amounts of the total, bacterial, and fungal phospholipid fatty acids (PLFAs) in soil. Moreover, the derived ratio of bacteria to fungi decreased significantly with incremental SMX and Cu, and principal component analysis of the PLFAs showed that soil microbial composition was significantly affected by SMX interacted with Cu at 500 mg kg(-1). All of these results indicated that the interaction of SMX and Cu was synergistic to amplify the negative effect of SMX on soil microbial biomass, structural composition, and even the enzymatic function.

Evaluation and development of soil values for the pathway 'soil to plant'. Significance of mercury evaporation for the burden of plants

International Nuclear Information System (INIS)

Gaeth, S.; Schlueter, K.

1998-05-01

In cooperation with the Ad-hoc working group 'Transfer of heavy metals from soil to plant' of the Laenderarbeitsgemeinschaft Bodenschutz (LABO) the significance of mercury evaporation for the deduction of threshold values in respect of the impact via the pathway soil to plant was investigated. Mercury contamination of food- and feeding stuff plants was examined with special emphasis. For these purposes a lab experiment including three different soils with varying initial mercury load (background level, geogenic and anthropogenic contamination) and two different plant species (parsely and spinach) was carried out under defined conditions in closed lysimeters. Mercury uptake via the roots was minimised since the plants grew in isolated customary substrate which showed a low concentration of mercury. Thus, only the surrounding soil evaporated mercury. The concentrations of mercury in the plants in the background level treatment (0.1 mg Hg/kg dry soil) were 0.15 mg/kg dry matter (spinach) and 0.44 mg/kg dry matter (parsely). The treatment with anthropogenic contaminated soil (111 mg Hg/kg dry soil) resulted in concentrations in the two plants of 2.0 and 2.6 mg/kg dry matter, respectively. A comparable order of magnitude was achieved in the geogenic contaminated treatment (34 mg Hg/kg dry soil) with 2.1 mg/kg dry matter. Experiments conducted with radioactive 203 Hg showed in each case recoveries of 20 to 34% in the leaves regarding the evaporated Hg-tracer. Also in the stem and in the roots Hg-tracer could be detected, indicating a translocation within the plant from leaf to root. By means of a comprehensive literature study the state of the art for Hg-evaporation and Hg-uptake of plants was compiled. Comparing the experimental results with data derived from literature, the Hg-concentrations found are confirmed by results of other authors. (orig.) [de

Derivation of soil screening thresholds to protect chisel-toothed kangaroo rat from uranium mine waste in northern Arizona

Science.gov (United States)

Hinck, Jo E.; Linder, Greg L.; Otton, James K.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.

2013-01-01

Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes.

Uranium uptake and accumulation in plants from soil contaminated with uranium in different concentrations

International Nuclear Information System (INIS)

Zhao Luxue; Tang Yongjin; Luo Xuegang

2014-01-01

The plants of Medicago sativa L., Hibiscus esulentus L, Waterspinach, Amaranthus retroflexus and Abutilon theophrasti Medic were employed as the indicator to investigate the uranium uptake and accumulation from soils contaminated with uranium (UO_2 (CH_3COO)_2 · 2H_2O) of 25 mg · kg"-"l, 75 mg · kg"-"1, 125 mg · kg"-"l, 175 mg · kg"-"l respectively, in a pot experiment. The result shows that, U concentration in the aerial part and underground part of the whole plant increased with the rise of uranium concentration in the soils. In the contaminated soils with 25∼125 mg · kg"-"l concentrations of uranium, U content of Medicago sativa L is the highset (6.78 mg · kg"-"l, 61.53 mg · kg"-"l, 74.06 mg · kg"-"l separately). While in the 175 mg · kg"-"l concentration of uranium contaminated soils, U content of Hibiscus esulentus L is the highest (86.72 mg · kg"-"1), which is mainly because of U concentration in its roots have higher level of uranium (388.16 mg · kg"-"l). Comprehensive analysis shows that Medicago sativa L. is a good plant for phytoextraction and Hibiscus esulentus L is a good immobilizing plant for phytoremediation. The results can provide some theoretical basis and technical support for remedying U-contaminated soils in different areas of our country. (authors)

Application of nanoparticle of rock phosphate and biofertilizer in increasing some soil chemical characteristics of variable charge soil

Science.gov (United States)

Devnita, Rina; Joy, Benny; Arifin, Mahfud; Hudaya, Ridha; Oktaviani, Nurul

2018-02-01

Soils in Indonesia are dominated by variable charge soils where the technology like fertilization did not give the same result as the soils with permanent charge. The objectives of this research is to increase some chemical characteristic of variable charge soils by using the high negative charge ameliorations like rock phosphate in nanoparticle combined with biofertilizer. The research used a complete randomized experimental design in factorial with two factors. The first factor was nanoparticle of rock phosphate consists of four doses on soil weight percentage (0%, 2.5%, 5.0% and 7.5%). The second factor was biofertilizer consisted of two doses (without biofertilizer and 1 g.kg-1 soil biofertilizer). The combination treatments replicated three times. Variable charge soil used was Andisol. Andisol and the treatments were incubated for 4 months. Soil samples were taken after one and four months during incubation period to be analyzed for P-retention, available P and potential P. The result showed that all combinations of rock phosphate and biofertilizer decreased the P-retention to 75-77% after one month. Independently, application of 7.5% of rock phosphate decreased P-retention to 87.22% after four months, increased available P (245.37 and 19.12 mg.kg-1) and potential P (1354.78 and 3000.99 mg/100) after one and four months. Independently, biofertilizer increased the P-retention to 91.66% after four months, decreased available P to 121.55 mg.kg-1 after one month but increased to 12.55 mg.kg-1 after four months, decreased potential P to 635.30 after one month but increased to 1810.40 mg.100 g-1 after four months.

Phytoextraction potential of sunflower and white mustard plants in zinc-contaminated soil

Directory of Open Access Journals (Sweden)

Marta Zalewska

2014-12-01

Full Text Available Phytoextraction relies on plants with a high capacity to absorb heavy metals and remove them from the soil. The objective of this study was to analyze the potential of sunflower (Helianthus annuus L. and white mustard (Sinapis alba L. for phytoextraction of Zn-contaminated soil. Research was based on a strict pot experiment conducted in a greenhouse. Seven treatments were established with increasing Zn concentrations: 0, 25, 50, 100, 200, 400, and 600 mg Zn kg-1 air-dry soil. The first tested plant was fodder sunflower. In the following year, white mustard was sown in the same pots. Plants were harvested at the end of the flowering stage. The toxic effect of Zn on sunflower yields occurred at the contamination level of 200 mg Zn kg-1 soil. In the second year of the experiment, a significant decrease in mustard biomass took place in response to 400 mg Zn kg-1 soil. The contamination level of 600 mg Zn kg-1 soil resulted in complete plant death. Plant growth was not inhibited even at high tissue Zn concentrations of 515 mg Zn kg-1 sunflower DM and 422 mg Zn kg-1 mustard DM. The 2-yr cropping system did not contribute to a significant decrease in soil Zn content. Despite high concentrations of Zn in sunflower and mustard plants, total Zn uptake accounted for only 1% to 8% of the Zn rate introduced into the soil. However, in the long run, the growing of crops could reduce Zn contamination levels in the soil. The relatively high tolerance of sunflower and white mustard for Zn contamination and rapid growth of these species are possible alternatives for phytoextraction and phytostabilization of Zn-contaminated soil.

Micro- and Macroelements Content in Soil, Plants Nectaro- Pollenifer Leaves, Pollen and Bees Body

Directory of Open Access Journals (Sweden)

Nicolae Eremia

2010-10-01

Full Text Available Taking into account the fact that quality and biological value of bee products depend on the chemical composition and taking account of the environmental situation, studying the content and dynamics of micro-, macro elements composition of soil, plant, bee products and bee body have theoretical and practical interest. Our research was conducted to determine the micro-and macro elements content in soil composition, nectar-pollen plant leaves, pollen, bee bread and body. Content of micro- and macro elements were determined by atomic spectroscopy method in the laboratory of the Institute of Atomic Spectroscopy Chemistry of the ASM. It was established that the soil composition is containing 5434,69 mg/kg micronutrients in nectar-pollen plant leaves - 319,3 mg/kg, pollen - 179,04 mg/kg, pasture - 152,7 mg/kg, honey - 5,01 mg/kg and the bee body - 103,76 mg/kg. It was revealed that the total quantity of studied macro elements in soil was 6230,1 mg/kg, nectar-pollen plant leaves - 54409,9 mg/kg, pollen - 13772,74 mg/kg, pasture - 9311,2 mg/kg in bee body - 24234,2 mg/kg.

Affects of wastewater discharge from mining on soil heavy metal pollution and enzyme activities in northern Hunan province, Central South China

Science.gov (United States)

Jiang, Ying; Hu, Xue-Feng; Shu, Ying; Yan, Xiao-Juan; Luo, Fan

2013-04-01

Hunan province, Central South China, is rich in mineral resources and also a well-known nonferrous metal base in China. Mining and ore processing there, however, are mostly conducted in indigenous methods, and thus causing heavy metal pollution of abundant farmland. Situated in northern Hunan province, Y county has antimony, manganese, vanadium, and pyrite mines, but still belongs to a region of rice cultivation, of which, paddy fields make up 84.5% of the total farmland. Our investigations found that irrigation water is threatened by the release of mining wastewater in the county. For example, a stream used for irrigation turns dark-red after long-term receiving wastewater discharged from a pyrite company at HS Town of the county. Concentrations of Cu, Zn, Cd, Fe and Mn in the stream water reach 0.03 mg kg-1, 2.14 mg kg-1, 0.02 mg kg-1, 96.0 mg kg-1 and 11.5 mg kg-1, respectively; these in the paddy soils nearby are 67.3 mg kg-1, 297 mg kg-1, 4.0 mg kg-1, 33.1 mg g-1 and 463 mg kg-1 on average, respectively, with a maximum of Cd reaching 16.8 mg kg-1. Microbial biomass and activities are significantly reduced by metal toxicity in the soils. The counts of fungal, actinomycin and bacterial colonies in the polluted soils are 8.8×103 /g (Fresh soil), 4.9×105 /g (Fresh soil) and 6.4×105 /g (Fresh soil), respectively, which are only 4.68%, 10.3% and 20.9% of these in non-polluted soils in Y county, respectively. Likewise, the microbial biomass (MB) - C and MB - N of the polluted soils are only 36.8% and 50.3% of these in the non-polluted, respectively. The activities of dehydrogenase, urease, catalase, acid and neutral phosphatase and sucrase in the polluted soils are only 41.2%, 49.8%, 56.8%, 69.9%, 80.7% and 81.0% of these in the non-polluted, respectively. There are significant negative correlations between Cu, Zn and Cd contents and the activities of dehydrogenase and catalase, suggesting that the two enzymes are the most sensitive to heavy metal toxicity in the

Selected Heavy Metals Content in Soil and Arundina graminifolia from Pelepah Kanan Mine, Kota Tinggi, Johor, Malaysia

International Nuclear Information System (INIS)

Sahibin Abdul Rahim; Zulfahmi Ali Rahman; Wan Mohd Razi Idris; Azman Hashim; Tukimat Lihan; Muhd Barzani Gasim; Jumaat Adam; Lim, F.N.

2009-01-01

Heavy metals composition of Cd, Co, Cr, Ni, Pb and Zn in Arundina graminifolia collected from mining area at Lombong Pelepah Kanan, Kota Tinggi, Johor were determined. The heavy metal content was also analysed in their soil substrates. The plants were separated into different portions for example root, stem and leaf and extracted for their heavy metal content by digestion method whereas the soils heavy metal content was extracted by sequential extraction. Heavy metal content in soil and plant extract was determined using the Flame Atomic Absorption Spectrophotometer. Heavy metal contents of Cd, Cr, Ni and Pb in plants were compared with their content in the control plant, whereas the Co and Zn contents were three to five folds higher. As for heavy metal content in different plant parts, it was found that Cd concentration was high in roots (2.03 mg/ kg) followed by leaf (1.67 mg/ kg) and stem (1.49 mg/ kg). Co concentration was high in leaf (9.26 mg/ kg) followed by root (9.18 mg/ kg) and stem (6.94 mg/ kg). For Cr, the concentration in decreasing sequence was root (0.46 mg/ kg) > leaf (0.19 mg/ kg) > stem (0.08 mg/ kg). Ni concentration was higher in leaf (2.78 mg/ kg) followed by root (2.71 mg/ kg) and stem (1.66 mg/ kg). Concentration in decreasing order was root (10.34 mg/ kg) > leaf (4.18 mg/ kg) > stem (3.75 mg/ kg). Zn concentration was higher in leaf (44.03 mg/ kg) followed by root (32.30 mg/ kg) and stem (13.21 mg/ kg). Total heavy metal content in soil was 2.07 - 5.59 mg/ kg, 8.72 - 39.93 mg/ kg, 1.81 - 2.14 mg/ kg, 2.66 - 6.87 mg/ kg, 23.02 - 51.56 mg/ kg and 0.64 - 2.61 mg/ kg for Ni, Zn, Cd, Pb, Co and Cr, respectively. The available fraction of heavy metals in soil was 21.9 % for Ni, 15.3 % for Zn, 49.9 % for Cd, 19.3 % for Pb, 45.7 % for Co and nil percent for Cr. Biological adsorption coefficient for the heavy metals studied was very low except for Zn where BAC value slightly higher than 1. This plant was not suitable to be used as a phyto

Eisenia fetida increased removal of polycyclic aromatic hydrocarbons from soil

Energy Technology Data Exchange (ETDEWEB)

Silvia M. Contreras-Ramos; Dioselina Alvarez-Bernal; Luc Dendooven [Laboratory of Soil Ecology, Department of Biotechnology and Bioengineering, Mexico (Mexico)

2006-06-15

The removal of phenanthrene, anthracene and benzo(a)pyrene added at three different concentrations was investigated with or without earthworms (Eisenia fetida) within 11 weeks. Average anthracene removal by the autochthonous micro-organisms was 23%, 77% for phenanthrene and 13% for benzo(a)pyrene, while it was 51% for anthracene, 47% for benzo(a)pyrene and 100% for phenanthrene in soil with earthworms. At 50 and 100 mg phenanthrene kg{sup -1} E. fetida survival was 91% and 83%, but at 150 mg kg{sup -1} all died within 15 days. Survival of E. fetida in soil amended with anthracene {<=}1000 mg kg{sup -1} and benzo(a)pyrene {<=}150 mg kg{sup -1} was higher than 80% and without weight loss compared to the untreated soil. Only small amounts of PAHs were detected in the earthworms. It was concluded that E. fetida has the potential to remove large amounts of PAHs from soil, but more work is necessary to elucidate the mechanisms involved.

Rimsulfuron in Soil: Effects on Microbiological Properties under Varying Soil Conditions

Directory of Open Access Journals (Sweden)

Ljiljana Radivojević

2011-01-01

Full Text Available The effects of rimsulfuron a sulfonylurea herbicide on the growth and activity of soil microorganisms under laboratory conditions was investigated in two soils. The application rates were: 0.2, 2.0 and 20.0 mg a.i kg-1 soil. The lowest concentration tested was the label rate (0.2 mg a.i kg-1, and the other two were ten and hundred timeshigher. No adverse effects on microbiological processes were observed for the label rate. Decrease in microbial biomass carbon, dehydrogenase activity, fungi and bacteria in comparison with untreated control, were found at higher rates. The magnitude of these effects were generally slight and transitory.

Effect of long-term zinc pollution on soil microbial community resistance to repeated contamination.

Science.gov (United States)

Klimek, Beata

2012-04-01

The aim of the study was to compare the effects of stress (contamination trials) on the microorganisms in zinc-polluted soil (5,018 mg Zn kg(-1) soil dry weight) and unpolluted soil (141 mg Zn kg(-1) soil dw), measured as soil respiration rate. In the laboratory, soils were subjected to copper contamination (0, 500, 1,500 and 4,500 mg kg(-1) soil dw), and then a bactericide (oxytetracycline) combined with a fungicide (captan) along with glucose (10 mg g(-1) soil dw each) were added. There was a highly significant effect of soil type, copper treatment and oxytetracycline/captan treatment. The initial respiration rate of chronically zinc-polluted soil was higher than that of unpolluted soil, but in the copper treatment it showed a greater decline. Microorganisms in copper-treated soil were more susceptible to oxytetracycline/captan contamination. After the successive soil contamination trials the decline of soil respiration was greater in zinc-polluted soil than in unpolluted soil.

Eisenia fetida increased removal of polycyclic aromatic hydrocarbons from soil

Energy Technology Data Exchange (ETDEWEB)

Contreras-Ramos, Silvia M. [Laboratory of Soil Ecology, Department of Biotechnology and Bioengineering, Cinvestav, Av. Instituto Politecnico Nacional 2508, C.P. 07000 Mexico, D.F. (Mexico); Alvarez-Bernal, Dioselina [Laboratory of Soil Ecology, Department of Biotechnology and Bioengineering, Cinvestav, Av. Instituto Politecnico Nacional 2508, C.P. 07000 Mexico, D.F. (Mexico); Dendooven, Luc [Laboratory of Soil Ecology, Department of Biotechnology and Bioengineering, Cinvestav, Av. Instituto Politecnico Nacional 2508, C.P. 07000 Mexico, D.F. (Mexico)]. E-mail: dendoove@cinvestav.mx

2006-06-15

The removal of phenanthrene, anthracene and benzo(a)pyrene added at three different concentrations was investigated with or without earthworms (Eisenia fetida) within 11 weeks. Average anthracene removal by the autochthonous micro-organisms was 23%, 77% for phenanthrene and 13% for benzo(a)pyrene, while it was 51% for anthracene, 47% for benzo(a)pyrene and 100% for phenanthrene in soil with earthworms. At 50 and 100 mg phenanthrene kg{sup -1} E. fetida survival was 91% and 83%, but at 150 mg kg{sup -1} all died within 15 days. Survival of E. fetida in soil amended with anthracene {<=}1000 mg kg{sup -1} and benzo(a)pyrene {<=}150 mg kg{sup -1} was higher than 80% and without weight loss compared to the untreated soil. Only small amounts of PAHs were detected in the earthworms. It was concluded that E. fetida has the potential to remove large amounts of PAHs from soil, but more work is necessary to elucidate the mechanisms involved. - Addition of earthworms, Eisenia fetida, accelara removal of polycyclic aromatic hydrocarbons from soil.

Eisenia fetida increased removal of polycyclic aromatic hydrocarbons from soil

International Nuclear Information System (INIS)

Contreras-Ramos, Silvia M.; Alvarez-Bernal, Dioselina; Dendooven, Luc

2006-01-01

The removal of phenanthrene, anthracene and benzo(a)pyrene added at three different concentrations was investigated with or without earthworms (Eisenia fetida) within 11 weeks. Average anthracene removal by the autochthonous micro-organisms was 23%, 77% for phenanthrene and 13% for benzo(a)pyrene, while it was 51% for anthracene, 47% for benzo(a)pyrene and 100% for phenanthrene in soil with earthworms. At 50 and 100 mg phenanthrene kg -1 E. fetida survival was 91% and 83%, but at 150 mg kg -1 all died within 15 days. Survival of E. fetida in soil amended with anthracene ≤1000 mg kg -1 and benzo(a)pyrene ≤150 mg kg -1 was higher than 80% and without weight loss compared to the untreated soil. Only small amounts of PAHs were detected in the earthworms. It was concluded that E. fetida has the potential to remove large amounts of PAHs from soil, but more work is necessary to elucidate the mechanisms involved. - Addition of earthworms, Eisenia fetida, accelara removal of polycyclic aromatic hydrocarbons from soil

Effects of silver sulfide nanomaterials on mycorrhizal colonization of tomato plants and soil microbial communities in biosolid-amended soil

International Nuclear Information System (INIS)

Judy, Jonathan D.; Kirby, Jason K.; Creamer, Courtney; McLaughlin, Mike J.; Fiebiger, Cathy; Wright, Claire; Cavagnaro, Timothy R.; Bertsch, Paul M.

2015-01-01

We investigated effects of Ag_2S engineered nanomaterials (ENMs), polyvinylpyrrolidone (PVP) coated Ag ENMs (PVP-Ag), and Ag"+ on arbuscular mycorrhizal fungi (AMF), their colonization of tomato (Solanum lycopersicum), and overall microbial community structure in biosolids-amended soil. Concentration-dependent uptake was measured in all treatments. Plants exposed to 100 mg kg"−"1 PVP-Ag ENMs and 100 mg kg"−"1 Ag"+ exhibited reduced biomass and greatly reduced mycorrhizal colonization. Bacteria, actinomycetes and fungi were inhibited by all treatment classes, with the largest reductions measured in 100 mg kg"−"1 PVP-Ag ENMs and 100 mg kg"−"1 Ag"+. Overall, Ag_2S ENMs were less toxic to plants, less disruptive to plant-mycorrhizal symbiosis, and less inhibitory to the soil microbial community than PVP-Ag ENMs or Ag"+. However, significant effects were observed at 1 mg kg"−"1 Ag_2S ENMs, suggesting that the potential exists for microbial communities and the ecosystem services they provide to be disrupted by environmentally relevant concentrations of Ag_2S ENMs. - Highlights: • PVP-Ag and Ag"+ inhibited AMF colonization more readily than Ag_2S ENMs. • Impact of PVP-Ag ENMs and Ag"+ on microbial communities larger than for Ag_2S ENMs. • Significant changes in microbial communities in response to Ag_2S ENMs at 1 mg kg"−"1. - Although Ag_2S ENMs are less toxic to soil microorganisms than pristine nanomaterials or ions, some effects are observed on soil microbial communities at relevant concentrations.

Chelate-assisted phytoextraction of lead from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Cooper, E.M.; Sims, J.T.; Cunningham, S.D.; Huang, J.W.; Berti, W.R.

1999-12-01

Phytoextraction, a remediation strategy for lead (Pb)-contaminated soils that removes soil Pb through plant uptake and harvest, may be enhanced by use of synthetic chelates. The authors evaluated Pb desorption from four contaminated soils by seven chelates (CDTA, DTPA, EDDHA, EFTA, HEDTA, HEIDA, and NTA) at three rates. The three most effective chelates (CDTA, DTPA, and HEDTA) were used in greenhouse studies with an uncontaminated soil and a Pb-contaminated soil to determine the effect of chelate type and rate on growth, Pb uptake, and plant elemental composition. Lead desorption varied with chelate and soil and increased with chelate rate, averaging 948 mg Pb kg{sup {minus}1} at the 20 mmol kg{sup {minus}1} rate vs. 28 mg Pb kg{sup {minus}1} by the control. The general ranking of chelate effectiveness, based on total Pb desorbed, was HEDTA > CDTA > DTPA > EGTA > HEIDA > EDDHA {approximately} NTA. Plant uptake of Pb from the contaminated soil was enhanced by CDTA, DTPA, and HEDTA, but with even the most effective treatment (corn, high CDTA rate), the amount of Pb extracted by plants was rather low. Lead extractable by the Toxicity Characteristic Leaching Procedure (TCLP) was increased from 9 mg L{sup {minus}1} in the control to from 47 to 174 mg L{sup {minus}1} in soils treated with 20 mmol kg{sup {minus}1} CDTA or DTPA and chelates generally caused a shift in Pb from resistant to more soluble chemical fractions.

Cs phytoremediation by Sorghum bicolor cultivated in soil and in hydroponic system.

Science.gov (United States)

Wang, Xu; Chen, Can; Wang, Jianlong

2017-04-03

Cs accumulation characteristics by Sorghum bicolor were investigated in hydroponic system (Cs level at 50-1000 μmol/L) and in soil (Cs-spiked concentration was 100 and 400 mg/kg soil). Two varieties of S. bicolor Cowly and Nengsi 2# grown on pot soil during the entire growth period (100 days) did not show significant differences on the height, dry weight (DW), and Cs accumulation. S. bicolor showed the potential phytoextraction ability for Cs-contaminated soil with the bioaccumulation factor (BCF) and the translocation factor (TF) values usually higher than 1 in soil system and in hydroponic system. The aerial parts of S. bicolor contributed to 86-92% of the total removed amounts of Cs from soil. Cs level in solution at 100 μmol/L gave the highest BCF and TF values of S. bicolor. Cs at low level tended to transfer to the aerial parts, whereas Cs at high level decreased the transfer ratio from root to shoot. In soil, the plant grew well when Cs spiked level was 100 mg/kg soil, but was inhibited by Cs at 400 mg/kg soil with Cs content in sorghum reaching 1147 mg/kg (roots), 2473 mg/kg (stems), and 2939 mg/kg (leaves). In hydroponic system, average Cs level in sorghum reached 5270 mg/kg (roots) and 4513 mg/kg (aerial parts), without significant damages to its biomass at 30 days after starting Cs treatment. Cs accumulation in sorghum tissues was positively correlated with the metal concentration in medium.

Does Biochar Addition Inlfuence the Change Points of Soil Phosphorus Leaching?

Institute of Scientific and Technical Information of China (English)

ZHAO Xiao-rong; LI Dan; KONG Juan; LIN Qi-mei

2014-01-01

Phosphorus change point indicating the threshold related to P leaching, largely depends on soil properties. Increasing data have shown that biochar addition can improve soil retention capacity of ions. However, we have known little about weather biochar amendment inlfuence the change point of P leaching. In this study, two soils added with 0, 5, 10, 20, and 50 g biochar kg-1 were incubated at 25°C for 14 d following adjusting the soil moisture to 50%water-holding capacity (WHC). The soils with different available P values were then obtained by adding a series of KH2PO4 solution (ranging from 0 to 600 mg P kg-1 soil), and subjecting to three cycles of drying and rewetting. The results showed that biochar addition signiifcantly lifted the P change points in the tested soils, together with changes in soil pH, organic C, Olen-P and CaCl2-P but little on exchangeable Ca and Mg, oxalate-extractable Fe and Al. The Olsen-P at the change points ranged from 48.65 to 185.07 mg kg-1 in the alluvial soil and 71.25 to 98.65 mg kg-1 in the red soil, corresponding to CaCl2-P of 0.31-6.49 and 0.18-0.45 mg L-1, respectively. The change points of the alluvial soil were readily changed by adding biochar compared with that of the red soil. The enhancement of change points was likely to be explained as the improvement of phosphate retention ability in the biochar-added soils.

Transfer of 137Cs to plants from two types of soil

International Nuclear Information System (INIS)

Skowronska-Smolak, M.; Pietrzak-Flis, S.

1994-01-01

Transfer of 137 Cs from soil to plants was studied in two types of soil: sandy soil (I) and sandy loam soil (II). The study was performed on an experimental field for of 1991 (soil I) and for 1992-93 (soil II). Transfer of 137 Cs from soil I was examined for spring barley, spring wheat, red beet, lettuce and kale; transfer from soil II was examined for winter barley, grass, alfalfa, potato tubers, red beet, radish, bean, spinach and lettuce. 137 Cs and potassium in plants and soil were determined using gamma spectrometry. The soils were characterized by particle size distribution and such chemical properties as pH H 2 O , pH KCl , content of organic matter, Ca, Mg and exchangeable K. The concentration of 137 Cs in the soil I was over five times lower than in soil II, being equal to 8.84±0.32 Bq kg -1 and 50.38±2.21 Bq kg -1 , respectively. The soils differ in their chemical characteristics and texture. Soil I contains 6.47±0.21 g kg -1 potassium, 0.147±0.015 g kg -1 exchangeable potassium, 2.21±0.32 g kg -1 Ca, 0.055±0.013 g kg -1 Mg and 1.733% organic matter. Soil II contains 10.87±0.22 g kg -1 potassium, 0.082±0.007 g kg -1 exchangeable potassium, 1.62±0.16 g kg -1 Ca, 0.097±0.009 g kg -1 Mg and 2.307% organic matter; pH H2O of soil I was equal to 7.40 and of soil II - 6.56. The lowest concentrations of 137 Cs for both soils were observed in cereals (spring wheat - 0.67±0.06 Bq kg -1 dw and spring barley - 0.33± Bq kg -1 dw for soil I and winter barley - 0.79±0.20 Bq kg -1 dw for soil II). The highest concentrations of this isotope were found in red beet leaves (9.11±1.38 Bq kg -1 dw for soil I and 16.44±1.14 Bq kg -1 dw for soil II). Transfer of 137 Cs to plants from the sandy loam soil was from about 2 up to about 7 times lower than from the sandy soil. The lower transfer of 137 Cs from soil II to plants in comparison to soil I might be associated with the presence of clay which binds Cs strongly. The strong binding of Cs in soil II can also be

Distribution Pattern of Polyaromatic Hydrocarbons (PAHs) in Soils in ...

African Journals Online (AJOL)

Distribution Pattern of Polyaromatic Hydrocarbons (PAHs) in Soils in the Vicinity of Fuel Stations in Abraka, Nigeria. ... (0.00191mg.kg-1). Investigation also reveals that all tested samples are contaminated, with mean values ranging between 0.000207±0.00026mg.kg-1 and 0.002123±0.00303mg.kg-1. Similarly, spearmen's ...

Morphological and functional responses of a metal-tolerant sunflower mutant line to a copper-contaminated soil series.

Science.gov (United States)

Kolbas, Aliaksandr; Kolbas, Natallia; Marchand, Lilian; Herzig, Rolf; Mench, Michel

2018-04-02

The potential use of a metal-tolerant sunflower mutant line for biomonitoring Cu phytoavailability, Cu-induced soil phytotoxicity, and Cu phytoextraction was assessed on a Cu-contaminated soil series (13-1020 mg Cu kg -1 ) obtained by fading a sandy topsoil from a wood preservation site with a similar uncontaminated soil. Morphological and functional plant responses as well as shoot, leaf, and root ionomes were measured after a 1-month pot experiment. Hypocotyl length, shoot and root dry weight (DW) yields, and leaf area gradually decreased as soil Cu exposure rose. Their dose-response curves (DRC) plotted against indicators of Cu exposure were generally well fitted by sigmoidal curves. The half-maximal effective concentration (EC 50 ) of morphological parameters ranged between 203 and 333 mg Cu kg -1 soil, corresponding to 290-430 μg Cu L -1 in the soil pore water, and 20 ± 5 mg Cu kg -1 DW in the shoots. The EC 10 for shoot Cu concentration (13-15 mg Cu kg -1 DW) coincided to 166 mg Cu kg -1 soil. Total chlorophyll content and total antioxidant capacity (TAC) were early biomarkers (EC 10 : 23 and 51 mg Cu kg -1 soil). Their DRC displayed a biphasic response. Photosynthetic pigment contents, e.g., carotenoids, correlated with TAC. Ionome was changed in Cu-stressed roots, shoots, and leaves. Shoot Cu removal peaked roughly at 280 μg Cu L -1 in the soil pore water.

Measured soil water concentrations of cadmium and zinc in plant pots and estimated leaching outflows from contaminated soils

DEFF Research Database (Denmark)

Holm, P.E.; Christensen, T.H.

1998-01-01

Soil water concentrations of cadmium and zinc were measured in plant pots with 15 contaminated soils which differed in origin, texture, pH (5.1-7.8) and concentrations of cadmium (0.2-17 mg Cd kg(-1)) and zinc (36-1300 mg Zn kg(-1)). The soil waters contained total concentrations of 0.5 to 17 mu g...... to 0.1% per year of the total soil content of cadmium and zinc. The measured soil water concentrations of cadmium and zinc did not correlate linearly with the corresponding soil concentrations but correlated fairly well with concentrations measured in Ca(NO(3))(2) extracts of the soils and with soil...... water concentrations estimated from soil concentrations and pH. Such concentration estimates may be useful for estimating amounts of cadmium and zinc being leached from soils....

Residues of cypermethrin and endosulfan in soils of Swat valley

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M. Nafees

2009-05-01

Full Text Available Swat Valley was studied for two widely used pesticides; cypermethrin and endosulfan. A total of 63 soil samples were collected from 27 villages selected for this purpose. The collected soil samples were extracted with n-hexane, pesticides were separated, identified and quantified by a GC-ECD system. Endosulfan was 0.24 - 1.51 mg kg-1 and 0.13 - 12.67 mg kg-1 in rainfed and irrigated areas, respectively. The residual level of cypermethrin was comparatively high with a level of0.14 to 27.62 mg kg-1 and 0.05 to 73.75 mg kg-1 in rainfed and irrigated areas, respectively. For assessing the possible causes of pesticide residues in soil, 360 farmers were interviewed. It was found that both, cypermethrin and endosulfan, apart from agriculture were also widely misused for fishing in the entire stretch of River Swat and its tributaries. River Swat is used for irrigation in Swat Valley and this wide misuse of pesticides can also contribute to pesticide residue in soil.

Effects of silver nanoparticles (NM-300K) on Lumbricus rubellus earthworms and particle characterization in relevant test matrices including soil

NARCIS (Netherlands)

Ploeg, M.J.C. van der; Handy, R.D.; Waalewijn-Kool, P.L.; Berg, J.H.J. van den; Herrera Rivera, Z.E.; Bovenschen, J.; Molleman, B.; Baveco, J.M.; Tromp, P.; Peters, R.J.B.; Koopmans, G.F.; Rietjens, I.M.C.M.; Brink, N.W. van den

2014-01-01

The impact of silver nanoparticles (AgNP; at 0mg Ag/kg, 1.5mg Ag/kg, 15.4mg Ag/kg, and 154mg Ag/kg soil) and silver nitrate (AgNO3; 15.4mg Ag/kg soil) on earthworms, Lumbricus rubellus, was assessed. A 4-wk exposure to the highest AgNP treatment reduced growth and reproduction compared with the

Intravenous rocuronium 0.3 mg/kg improves the conditions for tracheal intubation in cats: a randomized, placebo-controlled trial.

Science.gov (United States)

Sakai, Daniel M; Zornow, Kailee Anne; Campoy, Luis; Cable, Christina; Appel, Leslie D; Putnam, Holly J; Martin-Flores, Manuel

2018-01-01

Objectives We evaluated the use of rocuronium 0.3 mg/kg intravenously (IV) to facilitate tracheal intubation in cats anesthetized for elective ovariohysterectomy. Methods Thirty female cats were randomly allocated to receive rocuronium 0.3 mg/kg IV or an equal volume of normal saline, following induction of anesthesia with ketamine and midazolam. Thirty seconds after induction, a single investigator, unaware of treatment allocation, attempted tracheal intubation. The number of attempts and the time to complete intubation were measured. Intubating conditions were assessed as acceptable or unacceptable based on a composite score consisting of five different components. Duration of apnea after induction was measured and cases of hemoglobin desaturation (SpO 2 rocuronium 12 s [range 8-75 s]; saline 60 s [range 9-120 s]) and with fewer attempts (rocuronium 1 [range 1-2]; saline 2 [range 1-3], both P = 0.006) in cats receiving rocuronium. Unacceptable intubating conditions on the first attempt occurred in 3/15 cats with rocuronium and in 10/15 with saline ( P = 0.01). Apnea lasted 4 ± 1.6 mins with rocuronium and 2.3 ± 0.5 mins with saline ( P = 0.0007). No cases of desaturation were observed. Conclusions and relevance Rocuronium 0.3 mg/kg IV improves intubating conditions compared with saline and reduces the time and number of attempts to intubate with only a short period of apnea in cats.

Inorganic Phosphorus Fractions and Their Relationships with Soil Characteristics of Selected Calcareous Soils of Fars Province

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abolfazl azadi

2017-01-01

sequential fractionation scheme was preformed according to the method described by Jiang and Gu (1989. Olsen-P fraction that was extracted by NaHCO3 (Olsen and Sommers 1982 was regarded as P-availability index. Also, Total-P by perchloric acid (HClO4 digestion (Sparks; 1996 and organic P were determined.. All of the extraction procedures were performed in duplicate and the amounts of P were colorimetrically measured in the supernatants by the ascorbic acid method of Murphy and Riley (1962.The relationships between forms of P and some of the soil properties were established using correlation method. Results and Discussion: The chemical data of the soils showed that soils were calcareous with CCE range between 9.94 to 74.27 % ( average 51.10% and pH range between 7.02 to 8.36 (average 7.85. Also, the amounts of CEC were between 5.35 to 29.39 cmol (+ kg-1(average 16.68 cmol (+ kg-1. The results showed a wide range in content of Phosphorus fractions. The amount of total Phosphate ranged from 301.87 to 1458.68 mg kg-1 with an average of 626.63 mg kg-1 . Calcium Phosphate ranged from 147.83 to 666.90 mg kg-1 with an average of 324.79 mg kg-1, that comprised 85 and 52 percent of inorganic and total Phosphorus, respectively. The amount of Fe-P ranged from 0.38 to 59.18 mg kg-1 with an average of 7.56 mg kg-1 that comprised 13.64 and 8.34 percent of inorganic and total Phosphorus, respectively. Also, the amount of Al-P ranged from 20.49 to 123.09 mg kg-1 with an average of 52.28 mg kg-1that comprised 1.97 and 1.21 percent of inorganic and total Phosphorus, respectively. The results of correlation study showed that available Phosphorus was significantly correlated with Ca2-P, Ca8-P, Al-P, Ca10-P, and Pt (total phosphorus. So, in calcareous soils, awareness of soil properties and phosphorus fractions and their relationships are important for evaluation of phosphorous status in soil and understanding of soil chemistry that influence soil fertility. Conclusion: The relative abundance of

Nickel, Cobalt, Chromium and Copper in agricultural and grazing land soils of Europe

Science.gov (United States)

Albanese, Stefano; Sadeghi, Martiya; De Vivo, Benedetto; Lima, Annamaria; Cicchella, Domenico; Dinelli, Enrico

2014-05-01

In the framework of the GEMAS (Geochemical Mapping of Agricultural and Grazing Land Soils) project, concentrations of Ni, Co, Cu and Cr were determined for the whole available dataset (2218 samples of agricultural soil and 2127 samples of grazing land soil) covering a total area of 5.6 million sq km all over Europe. The distribution pattern of Ni in the European soils (both agricultural and grazing land soils) shows the highest concentrations in correspondence with the Mediterranean area (especially in Greece, the Balcan Peninsula and NW Italy) with average values generally ranging between 40 mg/kg and 140 mg/kg and anomalous areas characterized by peaks higher than 2400 mg/kg. Concentrations between 10 mg/kg and 40 mg/kg characterize Continental Europe north of Alps and, partly, the Scandinavian countries. Lower concentrations (agricultural and grazing land soils. The maximum concentration peaks of Cobalt and Cr rise up to respectively 126 mg/kg and 696 mg/kg in agricultural soils and up to 255 mg/kg and 577 mg/kg in grazing land soils. Copper distribution in the soils collected across Europe, although has a general correspondence with the patterns of Ni, Co, Cr, shows some peculiarities. Specifically, Cu is characterized by high concentration values (up to 395 mg/kg in agricultural soils and 373 mg/kg in Grazing land soils) also in correspondence with the Roman Comagmatic Province and the south western coast of France characterized by a wide spread of vineyards.

Effects of lead contamination on soil microbial activity and rice physiological indices in soil-Pb-rice (Oryza sativa L.) system.

Science.gov (United States)

Zeng, Lu-Sheng; Liao, Min; Chen, Cheng-Li; Huang, Chang-Yong

2006-10-01

The effect of lead (Pb) treatment on the soil microbial activities (soil microbial biomass and soil basal respiration) and rice physiological indices were studied by greenhouse pot experiment. Pb was applied as lead acetate at six different levels in two different paddy soils, namely 0 (control), 100, 300, 500, 700, 900 mg kg-1 soil. The results showed that the application of Pb at lower level (500 mg Pb kg-1 soil), which might be the critical concentration of Pb causing a significant decline in the soil microbial activities. However, the degree of influence on soil microbial activities by Pb was related to the clay and organic matter contents of the soils. On the other hand, when the level of Pb treatments increased to 500 mg kg-1, there was ecological risk for both soil microbial activities and plants. The results also revealed that there was a consistent trend that the chlorophyll contents increased initially, and then decreased gradually with increase in Pb concentration. Pb was effective in inducing proline accumulation and its toxicity causes oxidative stress in rice plants. In a word, soil microbial activities and rice physiological indices, therefore, may be sensitive indicators reflecting environmental stress in soil-Pb-rice system.

Growth, reproduction and biochemical toxicity of chlorantraniliprole in soil on earthworms (Eisenia fetida).

Science.gov (United States)

Liu, Tong; Wang, Xiuguo; Chen, Dan; Li, Yiqiang; Wang, Fenglong

2018-04-15

Diamide insecticides have become the fourth most commonly used insecticide class in the world. Chlorantraniliprole (CAP) is a first-generation diamide insecticide with broad application potential. In this experiment, the eco-toxicity of CAP in soil at 0.1, 1.0, 5.0 and 10.0mg/kg on earthworms (Eisenia fetida) was evaluated during a 42 d exposure. More specifically, the environmental fate and transport of CAP between soil and earthworms was monitored during the exposure period. The present results indicated that the CAP contents of 0.1, 1.0, 5.0 and 10.0mg/kg treatments decreased to no more than 20% in the soil after 42 d of exposure. The accumulation of CAP in earthworms was 0.03, 0.58, 4.28 and 7.21mg/kg earthworm (FW) at 0.1, 1.0, 5.0 and 10.0mg/kg after 42 d of exposure. At 0.1mg/kg and 1.0mg/kg, CAP had no effect on earthworms during the exposure period. The weight of earthworms was significantly reduced at 5.0 and 10.0mg/kg at 28 and 42 days after CAP application. After the 14th day, CAP induced excess production of reactive oxygen species (ROS) at 5.0 and 10.0mg/kg, resulting in oxidative damage to biomacromolecules. We believe that CAP has a high risk potential for earthworms when used at 5.0 and 10.0mg/kg. Copyright © 2017 Elsevier Inc. All rights reserved.

Micronutrient Availability in Relation to Selected Soil Properties and landscape Position in Calcareous Soils of Golpayegan

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Mojtaba Fathi

2017-02-01

Full Text Available Introduction: Variety of soil reactions govern the distribution of metal micronutrients that includes complexation with organic and inorganic ligands, ion exchange, adsorption and desorption processes, precipitation and dissolution of solids and acid-based equilibria. The relative importance of these reactions depends on many factors such as soil physical, chemical, and mineralogical properties and the nature of metal ions. Environmental factors such as climate, physiographic position, and soil development may affect variability of some soil properties and thereby nutrient availability. The present research was conducted to find relationships between Iron, manganese, zinc, and copper availability and some major soil properties, physiographic condition and soil development. Materials and Methods: Golpayegan region is located in northwest of Isfahan province in central Iran. The mean elevation of the studied area is 1790 above sea level. Annual precipitation was about 244mm and mean monthly temperature ranges from -6 in January to 34°C in August. The soils were developed on different physiographic conditions including piedmont plains, alluvial-fan, plateaus, and flood plains belonging to Entisols and Aridisols. Soil samples (0–60 cm were collected from 98 grid points with 2000m distance in the agricultural area of Golpayegan. Particle size distribution, calcium carbonate, organic carbon, available potassium and phosphorus of the soils were measured by SWRI standard methods. Available Zn, Cu, Mn, and Fe were determined by addition of 10 g soil to 20mL 0.005M diethylentriaminepentacetic‏. The solutions were shaken for 2 h at 25°C, centrifuged, filtered, and Fe, Mn, Zn, and Cu concentrations were measured by an atomic absorption spectrophotometer. Results Discussion: Studied soils were developed on calcareous material and about 60% of samples have more than 20% of calcium carbonate. Available Fe ranged from 1.4 to 6.5 mg kg-1 (mean 15.8 mg kg-1

Influence of activated charcoal amendment to contaminated soil on dieldrin and nutrient uptake by cucumbers

Energy Technology Data Exchange (ETDEWEB)

Hilber, Isabel [Research Institute of Organic Agriculture, Ackerstrasse, CH-5070 Frick (Switzerland); Wyss, Gabriela S., E-mail: gabriela.wyss@fibl.or [Research Institute of Organic Agriculture, Ackerstrasse, CH-5070 Frick (Switzerland); Maeder, Paul [Research Institute of Organic Agriculture, Ackerstrasse, CH-5070 Frick (Switzerland); Bucheli, Thomas D. [Agroscope Reckenholz-Taenikon Research Station ART, Reckenholzstr. 191, CH-8046 Zuerich (Switzerland); Meier, Isabel; Vogt, Lea; Schulin, Rainer [Institute of Terrestrial Ecosystems, ETH Zuerich, Universitaetstr. 16, CH-8092 Zuerich (Switzerland)

2009-08-15

Activated charcoal (AC) amendments have been suggested as a promising, cost-effective method to immobilize organic contaminants in soil. We performed pot experiments over two years with cucumber (Cucumis sativus L.) grown in agricultural soil with 0.07 mg kg{sup -1} of weathered dieldrin and 0, 200, 400, and 800 mg AC per kg soil. Dieldrin fresh weight concentrations in cucumber fruits were significantly reduced from 0.012 to an average of 0.004 mg kg{sup -1}, and total uptake from 2 to 1 mug in the 800 mg kg{sup -1} AC treatment compared to the untreated soil. The treatment effects differed considerably between the two years, due to different meteorological conditions. AC soil treatments did neither affect the availability of nutrients to the cucumber plants nor their yield (total fruit wet weight per pot). Thus, some important prerequisites for the successful application of AC amendments to immobilize organic pollutants in agricultural soils can be considered fulfilled. - The addition of activated charcoal to soil reduced dieldrin residues in cucumbers and did not affect nutrients availability.

Influence of activated charcoal amendment to contaminated soil on dieldrin and nutrient uptake by cucumbers

International Nuclear Information System (INIS)

Hilber, Isabel; Wyss, Gabriela S.; Maeder, Paul; Bucheli, Thomas D.; Meier, Isabel; Vogt, Lea; Schulin, Rainer

2009-01-01

Activated charcoal (AC) amendments have been suggested as a promising, cost-effective method to immobilize organic contaminants in soil. We performed pot experiments over two years with cucumber (Cucumis sativus L.) grown in agricultural soil with 0.07 mg kg -1 of weathered dieldrin and 0, 200, 400, and 800 mg AC per kg soil. Dieldrin fresh weight concentrations in cucumber fruits were significantly reduced from 0.012 to an average of 0.004 mg kg -1 , and total uptake from 2 to 1 μg in the 800 mg kg -1 AC treatment compared to the untreated soil. The treatment effects differed considerably between the two years, due to different meteorological conditions. AC soil treatments did neither affect the availability of nutrients to the cucumber plants nor their yield (total fruit wet weight per pot). Thus, some important prerequisites for the successful application of AC amendments to immobilize organic pollutants in agricultural soils can be considered fulfilled. - The addition of activated charcoal to soil reduced dieldrin residues in cucumbers and did not affect nutrients availability.

Phytoremediation for co-contaminated soils of chromium and benzo[a]pyrene using Zea mays L.

Science.gov (United States)

Chigbo, Chibuike; Batty, Lesley

2014-02-01

A greenhouse experiment was carried out to investigate the single effect of benzo[a]pyrene (B[a]P) or chromium (Cr) and the joint effect of Cr-B[a]P on the growth of Zea mays, its uptake and accumulation of Cr, and the dissipation of B[a]P over 60 days. Results showed that single or joint contamination of Cr and B[a]P did not affect the plant growth relative to control treatments. However, the occurrence of B[a]P had an enhancing effect on the accumulation and translocation of Cr. The accumulation of Cr in shoot of plant significantly increased by ≥ 79 % in 50 mg kg(-1) Cr-B[a]P (1, 5, and 10 mg kg(-1)) treatments and by ≥ 86 % in 100 mg kg(-1) Cr-B[a]P (1, 5, and 10 mg kg(-1)) treatments relative to control treatments. The presence of plants did not enhance the dissipation of B[a]P in lower (1and 5 mg kg(-1)) B[a]P contaminated soils; however, over 60 days of planting Z. mays seemed to enhance the dissipation of B[a]P by over 60 % in 10 mg kg(-1) single contaminated soil and by 28 to 41 % in 10 mg kg(-1)B[a]P co-contaminated soil. This suggests that Z. mays might be a useful plant for the remediation of Cr-B[a]P co-contaminated soil.

Impact of model uncertainty on soil quality standards for cadmium in rice paddy fields

International Nuclear Information System (INIS)

Roemkens, P.F.A.M.; Brus, D.J.; Guo, H.Y.; Chu, C.L.; Chiang, C.M.; Koopmans, G.F.

2011-01-01

At present, soil quality standards used for agriculture do not consider the influence of pH and CEC on the uptake of pollutants by crops. A database with 750 selected paired samples of cadmium (Cd) in soil and paddy rice was used to calibrate soil to plant transfer models using the soil metal content, pH, and CEC or soil Cd and Zn extracted by 0.01 M CaCl 2 as explanatory variables. The models were validated against a set of 2300 data points not used in the calibration. These models were then used inversely to derive soil quality standards for Japonica and Indica rice cultivars based on the food quality standards for rice. To account for model uncertainty, strict soil quality standards were derived considering a maximum probability that rice exceeds the food quality standard equal to 10 or 5%. Model derived soil standards based on Aqua Regia ranged from less than 0.3 mg kg -1 for Indica at pH 4.5 to more than 6 mg kg -1 for Japonica-type cultivars in clay soils at pH 7. Based on the CaCl 2 extract, standards ranged from 0.03 mg kg -1 Cd for Indica cultivars to 0.1 mg kg -1 Cd for Japonica cultivars. For both Japonica and Indica-type cultivars, the soil quality standards must be reduced by a factor of 2 to 3 to obtain the strict standards. The strong impact of pH and CEC on soil quality standards implies that it is essential to correct for soil type when deriving national or local standards. Validation on the remaining 2300 samples indicated that both types of models were able to accurately predict (> 92%) whether rice grown on a specific soil will meet the food quality standard used in Taiwan. - Research highlights: → Cadmium uptake by Japonica and Indica rice varieties depends on soil pH and CEC. → Food safety based soil standards range from 0.3 (Indica) to 6 mg kg -1 (Japonica). → Model uncertainty leads to strict soil standards of less than 0.1 mg kg -1 for Indica. → Soil pH and CEC should be considered to obtain meaningful standards for agriculture.

The identification of 'hotspots' of heavy metal pollution in soil-rice systems at a regional scale in eastern China.

Science.gov (United States)

Li, Wanlu; Xu, Binbin; Song, Qiujin; Liu, Xingmei; Xu, Jianming; Brookes, Philip C

2014-02-15

Chinese agricultural soils and crops are suffering from increasing damage from heavy metals, which are introduced from various pollution sources including agriculture, traffic, mining and especially the flourishing private metal recycling industry. In this study, 219 pairs of rice grain and corresponding soil samples were collected from Wenling in Zhejiang Province to identify the spatial relationship and pollution hotspots of Cd, Cu, Ni and Zn in the soil-rice system. The mean soil concentrations of heavy metals were 0.316 mg kg(-1) for Cd, 47.3 mg kg(-1) for Cu, 31.7 mg kg(-1) for Ni and 131 mg kg(-1) for Zn, and the metal concentrations in rice grain were 0.132 mg kg(-1) for Cd, 2.46 mg kg(-1) for Cu, 0.223 mg kg(-1) for Ni and 17.4 mg kg(-1) for Zn. The coefficient of variability (CV) of soil Cd, Cu and rice Cd were 147%, 146% and 180%, respectively, indicating an extensive variability. While the CVs of other metals ranged from 23.4% to 84.3% with a moderate variability. Kriging interpolation procedure and the Local Moran's I index detected the locations of pollution hotspots of these four metals. Cd and Cu had a very similar spatial pattern, with contamination hotspots located simultaneously in the northwestern part of the study area, and there were obvious hotspots for soil Zn in the north area, while in the northeast for soil Ni. The existence of hotspots may be due to industrialization and other anthropogenic activities. An Enrichment Index (EI) was employed to measure the uptake of heavy metals by rice. The results indicated that the accumulation and availability of heavy metals in the soil-rice system may be influenced by both soil heavy metal concentrations and soil physico-chemical properties. Cross-correlograms quantitatively illustrated that EIs were significantly correlated with soil properties. Soil pH and organic matter were the most important factors controlling the uptake of heavy metals by rice. As results, positive measures should be taken into

Estimating soil zinc concentrations using reflectance spectroscopy

Science.gov (United States)

Sun, Weichao; Zhang, Xia

2017-06-01

Soil contamination by heavy metals has been an increasingly severe threat to nature environment and human health. Efficiently investigation of contamination status is essential to soil protection and remediation. Visible and near-infrared reflectance spectroscopy (VNIRS) has been regarded as an alternative for monitoring soil contamination by heavy metals. Generally, the entire VNIR spectral bands are employed to estimate heavy metal concentration, which lacks interpretability and requires much calculation. In this study, 74 soil samples were collected from Hunan Province, China and their reflectance spectra were used to estimate zinc (Zn) concentration in soil. Organic matter and clay minerals have strong adsorption for Zn in soil. Spectral bands associated with organic matter and clay minerals were used for estimation with genetic algorithm based partial least square regression (GA-PLSR). The entire VNIR spectral bands, the bands associated with organic matter and the bands associated with clay minerals were incorporated as comparisons. Root mean square error of prediction, residual prediction deviation, and coefficient of determination (R2) for the model developed using combined bands of organic matter and clay minerals were 329.65 mg kg-1, 1.96 and 0.73, which is better than 341.88 mg kg-1, 1.89 and 0.71 for the entire VNIR spectral bands, 492.65 mg kg-1, 1.31 and 0.40 for the organic matter, and 430.26 mg kg-1, 1.50 and 0.54 for the clay minerals. Additionally, in consideration of atmospheric water vapor absorption in field spectra measurement, combined bands of organic matter and absorption around 2200 nm were used for estimation and achieved high prediction accuracy with R2 reached 0.640. The results indicate huge potential of soil reflectance spectroscopy in estimating Zn concentrations in soil.

[Bidens maximowicziana's adsorption ability and remediation potential to lead in soils].

Science.gov (United States)

Wang, Hong-qi; Li, Hua; Lu, Si-jin

2005-11-01

Bidens maximowicziana's adsorption ability and remediation potential to lead were studied. The results show: (1) The Bidens maximowicziana has a strong adsorption to lead, the concentration of lead in plants increased linearly with the increase of lead concentration in soil. Then maximum concentration was 1509.3 mg x kg(-1) in roots and 2164.7 mg x kg(-1) in shoots when lead concentration in soil was 2000 mg x L(-1); (2) The lead concentration distribution order in the Bidens maximorwicziana is: leaf>stem>root>seed, which indicate that Bidens maximowicziana has a strong ability to transfer lead; (3) Uptaking ability differes in different vegetal periods. Maximum lead uptaking rate occured in the period of blooming for 40-60 days, in which daily uptake capacity was 15.81 mg x (kg x d)(-1) in roots and 19.83 mg x (kg x d)(-1) in shoots respectively. It can be concluded that Bidens maximowicziana appeares to be a moderate Pb accumulator making it suitable for phytoremediation of Pb contaminated soil.

Metal immobilization and phosphorus leaching after stabilization of pyrite ash contaminated soil by phosphate amendments.

Science.gov (United States)

Zupančič, Marija; Lavrič, Simona; Bukovec, Peter

2012-02-01

In this study we would like to show the importance of a holistic approach to evaluation of chemical stabilization using phosphate amendments. An extensive evaluation of metal stabilization in contaminated soil and an evaluation of the leaching of phosphorus induced after treatment were performed. The soil was highly contaminated with Cu (2894 mg kg(-1)), Zn (3884 mg kg(-1)), As (247 mg kg(-1)), Cd (12.6 mg kg(-1)) and Pb (3154 mg kg(-1)). To immobilize the metals, mixtures of soil with phosphate (from H(3)PO(4) and hydroxyapatite (HA) with varying ratios) were prepared with a constant Pb : P molar ratio of 1: 10. The acetic acid extractable concentration of Pb in the mixture with the highest amount of added phosphoric acid (n(H(3)PO(4)) : n(HA) = 3 : 1) was reduced to 1.9% (0.62 mg L(-1)) of the extractable Pb concentration in the untreated soil, but the content of water extractable phosphorus in the samples increased from 0.04 mg L(-1) in the untreated soil sample up to 14.3 mg L(-1) in the same n(H(3)PO(4)) : n(HA) = 3 : 1 mixture. The high increase in arsenic mobility was also observed after phosphate addition. The PBET test showed phosphate induced reduction in Pb bioavailability. In attempting to stabilize Pb in the soil with the minimum treatment-induced leaching of phosphorus, it was found that a mixture of soil with phosphate addition in the molar ratio of H(3)PO(4) : HA of 0.75 : 1 showed the most promising results, with an acetic acid extractable Pb concentration of 1.35 mg L(-1) and a water extractable phosphorus concentration of 1.76 mg L(-1). The time-dependent leaching characteristics of metals and phosphorus for this mixture were evaluated by a column experiment, where irrigation of the soil mixture with the average annual amount of precipitation in Slovenia (1000 mm) was simulated. The phosphorus concentration in the leachates decreased from 2.60 mg L(-1) at the beginning of irrigation to 1.00 mg L(-1) at the end.

Phytostabilization potential of ornamental plants grown in soil contaminated with cadmium.

Science.gov (United States)

Zeng, Peng; Guo, Zhaohui; Cao, Xia; Xiao, Xiyuan; Liu, Yanan; Shi, Lei

2018-03-21

In a greenhouse experiment, five ornamental plants, Osmanthus fragrans (OF), Ligustrum vicaryi L. (LV), Cinnamomum camphora (CC), Loropetalum chinense var. rubrum (LC), and Euonymus japonicas cv. Aureo-mar (EJ), were studied for the ability to phytostabilization for Cd-contaminated soil. The results showed that these five ornamental plants can grow normally when the soil Cd content is less than 24.6 mg·kg -1 . Cd was mainly deposited in the roots of OF, LV, LC and EJ which have grown in Cd-contaminated soils, and the maximum Cd contents reached 15.76, 19.09, 20.59 and 32.91 mg·kg -1 , respectively. For CC, Cd was mainly distributed in the shoots and the maximum Cd content in stems and leaves were 12.5 and 10.71 mg·kg -1 , however, the total amount of Cd in stems and leaves was similar with the other ornamental plants. The enzymatic activities in Cd-contaminated soil were benefited from the five tested ornamental plants remediation. Soil urease and sucrase activities were improved, while dehydrogenase activity was depressed. Meanwhile, the soil microbial community was slightly influenced when soil Cd content is less than 24.6 mg·kg -1 under five ornamental plants remediation. The results further suggested that ornamental plants could be promising candidates for phytostabilization of Cd-contaminated soil.

Distribution of heavy metals in peri-urban agricultural areas soils

International Nuclear Information System (INIS)

Iram, S.; Ahmad, I.; Akhtar, S.

2012-01-01

In industry oriented peri-urban areas, the heavy metals accumulation in soils caused by industrialization has become a potential threat. The top soil sample from 48 agricultural fields were collected from a typical industry based peri-urban areas (Lahore, Faisalabad, Multan, Kasur, Islamabad, Wah Cantt.) of Punjab, Pakistan to study the accumulation and distribution of heavy metals (Pb, Cd, Cr, Cu, Ni and Zn) by atomic absorption spectrophotometer. The aim of the study was to investigate influence of an industrialized environment on the accumulation of heavy metals in peri-urban agricultural soils. The results of the study showed that the Pb content in the soil ranged from 17.24 to 126.4 mg/kg and the highest Pb content was observed in Islamabad soil samples, and the lowest in that of Multan area. The Cd content ranged from 1.1 to 4.0 mg/kg in Lahore while the highest Cr concentration level was 210.2 mg/kg and it was observed in Kasur and lowest 30.60 in that of Multan. The Cu content ranged from 31.2 to 127.9 mg/kg (Kasur-Lahore). The highest Ni concentration (82.0 mg/kg) was observed in Lahore from the urban area and the lowest level of 12.15 mg/kg was observed in Multan. The Zn content ranged from 42.5 to 267.7 mg/kg (Faisalabad-Wah Cantt). The study concluded that the concentration level of the heavy metals (Pb, Cd, Cu, Ni, Cr, Zn) in the studied peri-urban areas was higher as compared to heavy metal content of normal Dutch soil. High automobile traffic and industrial waste both are the most likely sources of the contamination of the peri urban areas of Pakistan. (author)

Geochemical pattern of soils in Bobovdol valley, Bulgaria. Assessment of Cd and Co contents

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Ivona Nikova

2016-07-01

Full Text Available The chemical composition of soils spread in the Bobov dol valley was studied in order to reveal the natural and anthropogenic patterns of Cd and Co spatial distribution. A sampling procedure based on the irregular grid of points and validated analytical methods were used in the field and laboratory studies. It is found that Cd content varies from 0.21 to 0.90 mg kg-1 in studied soils and the average value of 0.55 mg kg-1 coincides with concentration demarcating soil pollution (0.5 mg kg-1. Co content ranges from 2.22 to 15.76 mg kg-1 and in 70 % of sampled points exceeds the natural background content of 7.8 mg kg-1 found in local rocks. Still, Cd enrichment of studied soils is more significant than Co’s with coefficient of Clarke concentration of 3.67. Hence, the secondary deposition of studied elements as a result of the Bobov dol Thermal power plant air emissions is verified by results obtained. The spatial distribution of Cd and Co is featured with an altitudinal gradient in deposition and a trend of quantitative depletion in the South of Plant. Soil organic matter and pH have no influence on the content and spatial distribution of studied elements. Elements iron affinity governs their geochemical linkage in soils although cobalt occurs allied with aluminum and titanium.

Arsenic hyperaccumulation by Pteris vittata from arsenic contaminated soils and the effect of liming and phosphate fertilisation

International Nuclear Information System (INIS)

Caille, N.; Swanwick, S.; Zhao, F.J.; McGrath, S.P.

2004-01-01

Pot experiments were carried out to investigate the potential of phytoremediation with the arsenic hyperaccumulator Pteris vittata in a range of soils contaminated with As and other heavy metals, and the influence of phosphate and lime additions on As hyperaccumulation by P. vittata. The fern was grown in 5 soils collected from Cornwall (England) containing 67-4550 mg As kg -1 and different levels of metals. All soils showed a similar distribution pattern of As in different fractions in a sequential extraction, with more than 60% of the total As being associated with the fraction thought to represent amorphous and poorly-crystalline hydrous oxides of Fe and Al. The concentration of As in the fronds ranged from 84 to 3600 mg kg -1 , with 0.9-3.1% of the total soil As being taken up by P. vittata. In one soil which contained 5500 mg Cu kg -1 and 1242 mg Zn kg -1 , P. vittata suffered from phytotoxicity and accumulated little As (0.002% of total). In a separate experiment, neither phosphate addition (50 mg P kg -1 soil) nor liming (4.6 g CaCO 3 kg -1 soil) was found to affect the As concentration in the fronds of P. vittata, even though phosphate addition increased the As concentration in the soil pore water. Between 4 and 7% of the total soil As was taken up by P. vittata in 4 cuttings in this experiment. The results indicate that P. vittata can hyperaccumulate As from naturally contaminated soils, but may be suitable for phytoremediation only in the moderately contaminated soils

Arsenic hyperaccumulation by Pteris vittata from arsenic contaminated soils and the effect of liming and phosphate fertilisation

Energy Technology Data Exchange (ETDEWEB)

Caille, N.; Swanwick, S.; Zhao, F.J.; McGrath, S.P

2004-11-01

Pot experiments were carried out to investigate the potential of phytoremediation with the arsenic hyperaccumulator Pteris vittata in a range of soils contaminated with As and other heavy metals, and the influence of phosphate and lime additions on As hyperaccumulation by P. vittata. The fern was grown in 5 soils collected from Cornwall (England) containing 67-4550 mg As kg{sup -1} and different levels of metals. All soils showed a similar distribution pattern of As in different fractions in a sequential extraction, with more than 60% of the total As being associated with the fraction thought to represent amorphous and poorly-crystalline hydrous oxides of Fe and Al. The concentration of As in the fronds ranged from 84 to 3600 mg kg{sup -1}, with 0.9-3.1% of the total soil As being taken up by P. vittata. In one soil which contained 5500 mg Cu kg{sup -1} and 1242 mg Zn kg{sup -1}, P. vittata suffered from phytotoxicity and accumulated little As (0.002% of total). In a separate experiment, neither phosphate addition (50 mg P kg{sup -1} soil) nor liming (4.6 g CaCO{sub 3} kg{sup -1} soil) was found to affect the As concentration in the fronds of P. vittata, even though phosphate addition increased the As concentration in the soil pore water. Between 4 and 7% of the total soil As was taken up by P. vittata in 4 cuttings in this experiment. The results indicate that P. vittata can hyperaccumulate As from naturally contaminated soils, but may be suitable for phytoremediation only in the moderately contaminated soils.

The potential of willow for remediation of heavy metal polluted calcareous urban soils

International Nuclear Information System (INIS)

Jensen, Julie K.; Holm, Peter E.; Nejrup, Jens; Larsen, Morten B.; Borggaard, Ole K.

2009-01-01

Growth performance and heavy metal uptake by willow (Salix viminalis) from strongly and moderately polluted calcareous soils were investigated in field and growth chamber trials to assess the suitability of willow for phytoremediation. Field uptakes were 2-10 times higher than growth chamber uptakes. Despite high concentrations of cadmium (≥80 mg/kg) and zinc (≥3000 mg/kg) in leaves of willow grown on strongly polluted soil with up to 18 mg Cd/kg, 1400 mg Cu/kg, 500 mg Pb/kg and 3300 mg Zn/kg, it is unsuited on strongly polluted soils because of poor growth. However, willow proved promising on moderately polluted soils (2.5 mg Cd/kg and 400 mg Zn/kg), where it extracted 0.13% of total Cd and 0.29% of the total Zn per year probably representing the most mobile fraction. Cu and Pb are strongly fixed in calcareous soils. - Willow is suited for remediation of moderately heavy metal polluted calcareous soils

Tungsten (W) bioavailability in paddy rice soils and its accumulation in rice (Oryza sativa).

Science.gov (United States)

James, Blessing; Zhang, Weili; Sun, Pei; Wu, Mingyan; Li, Hong Hong; Khaliq, Muhammad Athar; Jayasuriya, Pathmamali; James, Swithin; Wang, Guo

2017-12-01

The aim of this study was to investigate the accumulation characteristics of tungsten (W) by different indica rice cultivars from the soil and to assess the potential risks to human health via dietary intake of W in rice consumption. A total of 153 rice (ear) samples of 15 cultivars and the corresponding surface soil samples were collected from 7 cities in Fujian Province of southeastern China. The available soil W were extracted using H 2 C 2 O 4 ·2H 2 O-(NH 4 ) 2 C 2 O 4 ·H 2 O at pH 3.3). Results showed that the total soil W ranged from 2.03 mg kg -1 to 15.34 mg kg -1  and available soil W ranged from 0.03 mg kg -1 to 1.61 mg kg -1 . The W concentration in brown rice varied from 7 μg kg -1 to 283 μg kg -1 and was significantly correlated with the available soil W. The highest mean TF avail (transfer factor based on available soil W) was 0.91 for Te-you 627 (hybrid, indica rice), whereas the lowest was 0.08 for Yi-you 673 (hybrid, indica rice). The TF avail decreased with the increase in available soil W, clay content, and cation exchange capacity. The consumption of the brown rice produced from the investigated areas in some cultivars by the present study may cause risks to human health.

Soil solution interactions may limit Pb remediation using P amendments in an urban soil

Science.gov (United States)

Lead (Pb) contaminated soils are a potential exposure hazard to the public. Amending soils with phosphorus (P) may reduce Pb soil hazards. Soil from Cleveland, OH containing 726 ± 14 mg Pb kg-1 was amended in a laboratory study with bone meal and triple super phospha...

Conscious Sedation Efficacy of 0.3 and 0.5 mg/kg Oral Midazolam for Three to Six Year-Old Uncooperative Children Undergoing Dental Treatment: A Clinical Trial

Directory of Open Access Journals (Sweden)

Masoud Fallahinejad Ghajari

2016-10-01

Full Text Available Objectives: Midazolam with variable dosages has been used to induce sedation in pediatric dentistry. The aim of this study was to compare the efficacy of two dosages of oral midazolam for conscious sedation of children undergoing dental treatment.Materials and Methods: In this randomized crossover double blind clinical trial, 20 healthy children (ASA I aged three to six years with negative or definitely negative Frankl behavioral rating scale were evaluated. Half of the children received 0.5mg/kg oral midazolam plus 1mg/kg hydroxyzine (A orally in the first session and 0.3mg/kg oral midazolam plus 1mg/kg hydroxyzine (B in the next session. The other half received the drugs on a reverse order. Sedation degree by Houpt sedation rating scale, heart rate and level of SpO2 were assessed at the beginning and after 15 and 30 minutes. The data were analyzed using SPSS 19 and Wilcoxon Signed Rank and McNemar’s tests.Results: The results showed that although administration of 0.5mg/kg oral midazolam was slightly superior to 0.3mg/kg oral midazolam in terms of sedation efficacy, the differences were not significant (P>0.05. The difference in treatment success was not significant either (P>0.05. Heart rate, oxygen saturation (SpO2 and respiratory rate were within the normal range and did not show a significant change (P>0.05.Conclusions: The overall success rate of the two drug combinations namely 0.5mg/kg oral midazolam plus hydroxyzine and 0.3mg/kg oral midazolam plus hydroxyzine was not significantly different for management of pediatric patients.Keywords: Conscious Sedation; Pediatric Dentistry; Midazolam; Hydroxyzine

Thermal-treated soil for mercury removal: Soil and phytotoxicity tests

Energy Technology Data Exchange (ETDEWEB)

Roh, Y.; Edwards, N.T.; Lee, S.Y.; Stiles, C.A.; Armes, S.; Foss, J.E.

2000-04-01

Mercury (Hg) contamination of soils and sediments is one of many environmental problems at the Oak Ridge Reservation, Oak Ridge, TN. Mercury-contaminated soil from the Lower East Fork Poplar Creek (LEFPC) at the Oak Ridge Reservation was treated thermally to reduce Hg concentration to a below target level (20 mg kg{sup {minus}1}) as a pilot scale thermal treatment demonstration. As a part of performance evaluation, the soil characteristics and plant growth response of the untreated and treated soil were examined. The soil treated at 350 C retained most of its original soil properties, but the soil treated at 600 C exhibited considerable changes in mineralogical composition and physicochemical characteristics. Growth and physiological response of the three plant species radish (Raphanus sativus L.), fescue (Festuca arundinacea Schreb.), and oat (Avena sativa L.) indicated adverse effects of the thermal treatment. The addition of N fertilizer had beneficial effects in the 350 C treated soil, but had little beneficial effect in the 600 C treated soil. Some changes of soil characteristics induced by thermal treatment cannot be avoided. Soil characteristics and phytotoxicity test results strongly suggest that changes occurring following the 350 C treatment do not limit the use of the treated soil to refill the excavated site for full-scale remediation. The only problem with the 350 C treatment is that small amounts of Hg compounds (<15 mg kg{sup {minus}1}) remain in the soil and a processing cost of $45/Mg.

Distribution of potentially toxic elements (PTEs) in tailings, soils, and plants around Gol-E-Gohar iron mine, a case study in Iran.

Science.gov (United States)

Soltani, Naghmeh; Keshavarzi, Behnam; Moore, Farid; Sorooshian, Armin; Ahmadi, Mohamad Reza

2017-08-01

This study investigated the concentration of potentially toxic elements (PTEs) including Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, V, and Zn in 102 soils (in the Near and Far areas of the mine), 7 tailings, and 60 plant samples (shoots and roots of Artemisia sieberi and Zygophylum species) collected at the Gol-E-Gohar iron ore mine in Iran. The elemental concentrations in tailings and soil samples (in Near and Far areas) varied between 7.4 and 35.8 mg kg -1 for As (with a mean of 25.39 mg kg -1 for tailings), 7.9 and 261.5 mg kg -1 (mean 189.83 mg kg -1 for tailings) for Co, 17.7 and 885.03 mg kg -1 (mean 472.77 mg kg -1 for tailings) for Cu, 12,500 and 400,000 mg kg -1 (mean 120,642.86 mg kg -1 for tailings) for Fe, and 28.1 and 278.1 mg kg -1 (mean 150.29 mg kg -1 for tailings) for Ni. A number of physicochemical parameters and pollution index for soils were determined around the mine. Sequential extractions of tailings and soil samples indicated that Fe, Cr, and Co were the least mobile and that Mn, Zn, Cu, and As were potentially available for plants uptake. Similar to soil, the concentration of Al, As, Co, Cr, Cu, Fe, Mn, Mo, Ni, and Zn in plant samples decreased with the distance from the mining/processing areas. Data on plants showed that metal concentrations in shoots usually exceeded those in roots and varied significantly between the two investigated species (Artemisia sieberi > Zygophylum). All the reported results suggest that the soil and plants near the iron ore mine are contaminated with PTEs and that they can be potentially dispersed in the environment via aerosol transport and deposition.

Residue dynamics of pyraclostrobin in peanut and field soil by QuEChERS and LC-MS/MS.

Science.gov (United States)

Zhang, Fengzu; Wang, Lei; Zhou, Li; Wu, Di; Pan, Hongji; Pan, Canping

2012-04-01

A modified QuEChERS-LC-MS/MS (acronym of quick, easy, cheap, effective, rugged and safe-liquid chromatography tandem mass spectrometry) method for the analysis of pyraclostrobin residue in peanut and soil was developed and validated. Pyraclostrobin residue dynamics and final residues in supervised field trials at Good Agricultural Practice (GAP) conditions in peanut and soil were studied. The limits of quantitation (LOQs) for pyraclostrobin in soil, plant, shell and peanut samples were 0.00057, 0.00026, 0.003 and 0.0037 mg kg(-1), respectively. At fortification levels of 0.005, 0.05 and 0.5 mg kg(-1) in all samples, it was shown that recoveries ranged from 80.3% to 109.4% with relative standard deviations of 1.1-8.2% (n=5). The dissipation experiments showed the half-lives (T(1/2)) of pyraclostrobin in soil and plants were 13.1-16.5 days and 10.3-11.2 days, respectively. At pre-harvest intervals (PHI) of 14, 21 and 28 days, pyraclostrobin residue were 0.005-0.20 mg kg(-1) in soil, 0.006-0.27 mg kg(-1) in plants, below 0.053 mg kg(-1) in shells and not detectable in peanuts. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

[Effects of fertilization on soil CO2 flux in Castanea mollissima stand].

Science.gov (United States)

Zhang, Jiao-Jiao; Li, Yong-Fu; Jiang, Pei-Kun; Zhou, Guo-Mo; Shen, Zhen-Ming; Liu, Juan; Wang, Zhan-Lei

2013-09-01

In June 2011-June 2012, a fertilization experiment was conducted in a typical Castanea mollissima stand in Lin' an of Zhejiang Province, East China to study the effects of inorganic and organic fertilization on the soil CO2 flux and the relationships between the soil CO2 flux and environmental factors. Four treatments were installed, i. e., no fertilization (CK), inorganic fertilization (IF), organic fertilization (OF), half organic plus half inorganic fertilization (OIF). The soil CO2 emission rate was determined by the method of static closed chamber/GC technique, and the soil temperature, soil moisture content, and soil water-soluble organic carbon (WSOC) concentration were determined by routine methods. The soil CO2 emission exhibited a strong seasonal pattern, with the highest rate in July or August and the lowest rate in February. The annual accumulative soil CO2 emission in CK was 27.7 t CO2 x hm(-2) x a(-1), and that in treatments IF, OF, and OIF was 29.5%, 47.0%, and 50.7% higher than the CK, respectively. The soil WSOC concentration in treatment IF (105.1 mg kg(-1)) was significantly higher than that in CK (76.6 mg x kg(-1)), but was obviously lower than that in treatments OF (133.0 mg x kg(-1)) and OIF (121.2 mg x kg(-1)). The temperature sensitivity of respiration (Q10) in treatments CK, IF, OF, and OIF was 1.47, 1.75, 1.49, and 1.57, respectively. The soil CO2 emission rate had significant positive correlations with the soil temperature at the depth of 5 cm and the soil WSOC concentration, but no significant correlation with soil moisture content. The increase of the soil WSOC concentration caused by fertilization was probably one of the reasons for the increase of soil CO2 emission from the C. mollissima stand.

Activity and functional diversity of microbial communities in long-term hydrocarbon and heavy metal contaminated soils

Directory of Open Access Journals (Sweden)

Markowicz Anna

2016-12-01

Full Text Available The impacts of long-term polycyclic aromatic hydrocarbons (PAHs and heavy metal pollution on soil microbial communities functioning were studied in soils taken from an old coke plant. The concentrations of PAHs in the tested soils ranged from 171 to 2137 mg kg-1. From the group of tested heavy metals, concentrations of lead were found to be the highest, ranging from 57 to 3478 mg kg-1, while zinc concentrations varied from 247 to 704 mg kg-1 and nickel from 10 to 666 mg kg-1. High dehydrogenase, acid and alkaline phosphatase activities were observed in the most contaminated soil. This may indicate bacterial adaptation to long-term heavy metal and hydrocarbon contamination. However, the Community Level Physiological Profiles (CLPPs analysis showed that the microbial functional diversity was reduced and influenced to a higher extent by some metals (Pb, Ni, moisture and conductivity than by PAHs.

Temporal changes of soil physic-chemical properties at different soil depths during larch afforestation by multivariate analysis of covariance.

Science.gov (United States)

Wang, Hui-Mei; Wang, Wen-Jie; Chen, Huanfeng; Zhang, Zhonghua; Mao, Zijun; Zu, Yuan-Gang

2014-04-01

Soil physic-chemical properties differ at different depths; however, differences in afforestation-induced temporal changes at different soil depths are seldom reported. By examining 19 parameters, the temporal changes and their interactions with soil depth in a large chronosequence dataset (159 plots; 636 profiles; 2544 samples) of larch plantations were checked by multivariate analysis of covariance (MANCOVA). No linear temporal changes were found in 9 parameters (N, K, N:P, available forms of N, P, K and ratios of N: available N, P: available P and K: available K), while marked linear changes were found in the rest 10 parameters. Four of them showed divergent temporal changes between surface and deep soils. At surface soils, changing rates were 262.1 g·kg(-1)·year(-1) for SOM, 438.9 mg·g(-1)·year(-1) for C:P, 5.3 mg·g(-1)·year(-1) for C:K, and -3.23 mg·cm(-3)·year(-1) for bulk density, while contrary tendencies were found in deeper soils. These divergences resulted in much moderated or no changes in the overall 80-cm soil profile. The other six parameters showed significant temporal changes for overall 0-80-cm soil profile (P: -4.10 mg·kg(-1)·year(-1); pH: -0.0061 unit·year(-1); C:N: 167.1 mg·g(-1)·year(-1); K:P: 371.5 mg·g(-1) year(-1); N:K: -0.242 mg·g(-1)·year(-1); EC: 0.169 μS·cm(-1)·year(-1)), but without significant differences at different soil depths (P > 0.05). Our findings highlight the importance of deep soils in studying physic-chemical changes of soil properties, and the temporal changes occurred in both surface and deep soils should be fully considered for forest management and soil nutrient balance.

Gross N transformation rates after application of household compost or domestic sewage sludge to agricultural soil

DEFF Research Database (Denmark)

Ambus, P.; Kure, L.K.; Jensen, E.S.

2002-01-01

Gross N mineralization and immobilization was examined in soil amended with compost and sewage sludge on seven occasions during a year using N-15 pool dilution and enrichment techniques. Gross N mineralization was initially stimulated with both wastes and accelerated through the first 112 days...... of incubation, peaking at 5 mg N.kg(-1).d(-1) with compost compared with 4 mg N.kg(-1).d(-1) in control and sludge-treated soil. The magnitudes of mineralization rates exceeded those of immobilization by on average 6.3 ( compost) and 11.4 ( sludge) times, leading to a persistent net N mineralization cumulating...... up to 160 mg N.kg(-1) soil(compost) and 54 mg N.kg(-1) soil (sludge) over the season from May to November. The numerical model FLUAZ comprehensively predicted rates of gross mineralization and immobilization. Sludge exhibited an early season N-release, whereas compost released only 10% of the N...

Soil acidification increases metal extractability and bioavailability in old orchard soils of Northeast Jiaodong Peninsula in China

International Nuclear Information System (INIS)

Li, Lianzhen; Wu, Huifeng; Gestel, Cornelis A.M. van; Peijnenburg, Willie J.G.M.; Allen, Herbert E.

2014-01-01

The bioavailability of Cu, Zn, Pb and Cd from field-aged orchard soils in a certified fruit plantation area of the Northeast Jiaodong Peninsula in China was assessed using bioassays with earthworms (Eisenia fetida) and chemical assays. Soil acidity increased with increasing fruit cultivation periods with a lowest pH of 4.34. Metals were enriched in topsoils after decades of horticultural cultivation, with highest concentrations of Cu (132 kg −1 ) and Zn (168 mg kg −1 ) in old apple orchards and Pb (73 mg kg −1 ) and Cd (0.57 mg kg −1 ) in vineyard soil. Earthworm tissue concentrations of Cu and Pb significantly correlated with 0.01 M CaCl 2 -extractable soil concentrations (R 2  = 0.70, p < 0.001 for Cu; R 2  = 0.58, p < 0.01 for Pb). Because of the increased bioavailability, regular monitoring of soil conditions in old orchards and vineyards is recommended, and soil metal guidelines need reevaluation to afford appropriate environmental protection under acidifying conditions. - Highlights: • Soil acidity of Chinese orchards increased with increasing fruit cultivation period. • Metal levels were enriched in topsoils after decades of horticultural cultivation. • Earthworm bioassays and chemical assays were used to assess metal bioavailability. • Earthworm Cu and Pb concentrations correlated with CaCl 2 -extractable concentrations. • Regular monitoring of soil conditions in old orchards and vineyards is recommended. - Long-term cultivation leads to increased acidification and metal accumulation in horticultural soils, with higher metal bioavailability to earthworms

Natural radioactive environment of urban soils in Shihezi, China

International Nuclear Information System (INIS)

Ge Benwei; Liu Anna

2009-01-01

Radionuclides, such as 238 U, 232 Th and 40 K, can be found in urban soil. To evaluate the natural radioactivity in the environment, soil samples were collected form Shihezi city and radioisotope concentrations were determined by X-ray fluorescence. The dose rate of urban soil (mGy per year, mGy/a) was calculated. The results indicate that the U, Th and K concentrations of the urban soils were, respectively, 1.2-3.2 mg/kg, 6.4-12.3 mg/kg and 2.05%-2.24%, with the mean values of 2.47 mg/kg, 10.47 mg/kg and 2.16 %. Dose rates of urban soils were 10.04-19.55 mGy/a with the mean value of 16.31 mGy/a. This dose rate is the perfect and maximum value of natural radiation in soil and different with the air absorbed dose rate from terrestrial γ-rays. The mean value of air absorbed dose rate was about 57.42 nGy/h. The annual effective dose rate in air was about 0.07 mSv/a and the average value of Ra eq in urban soil was 120.37 Bq/kg. The relative contribution of α particle to the dose rate is higher than that derived from β- and γ-rays in the urban soils. (authors)

Correlation between soil chemical characteristics and soil-borne mycoflora in cucumber tunnels

International Nuclear Information System (INIS)

Qudsia, H.; Javaid, A.; Mahmood, R.; Akhtar, N.

2017-01-01

Twelve soil samples were collected from fields of cucumber (Cucumis sativus L.) tunnels from various localities of Lahore and Shekhupura districts, Pakistan. Soil samples were analyzed for various characteristics viz. pH, EC/sub e/, organic matter, nitrogen (N), phosphorus (P) and potassium (K). Soil mycoflora was isolated using dilution plate method. Soil pH, EC/sub e/, organic matter, N, P and K were in the range of 7.42-8.13, 107-2520 (meu S cm-1), 0.98-1.40%, 0.039-0.070%, 7-357 mg kg/sup -1/ and 88-946 mg kg/sup -1/ in different soil samples, respectively. A total of 18 fungal species belonging to 10 genera viz. Aspergillus, Alternaria, Cladosporium, Drechslera, Emericella, Fusarium, Mortierella, Mucor, Penicillium and Sclerotium were isolated from various soil samples. Saprophytic fungi were more prevalent than pathogenic ones. Number of colonies of saprophytic fungi ranged from 360-2754 g/sup -1/ soil in different samples. In contrast, number of pathogenic fungal colonies were limited to 1-234 g/sup -1/ soil. Number of colonies of pathogenic fungi were positively and significantly correlated with soil organic matter and nitrogen contents. This study concludes that high nitrogen and organic matter in cucumber tunnels favour population of pathogenic fungi. (author)

Contamination and human health risk of lead in soils around lead/zinc smelting areas in China.

Science.gov (United States)

Lei, Kai; Giubilato, Elisa; Critto, Andrea; Pan, Huiyun; Lin, Chunye

2016-07-01

Pb/Zn smelting, an important economic activity in China, has led to heavy environmental pollution. This research reviewed studies on soil Pb contamination at Pb/Zn smelting sites in China published during the period of 2000 to 2015 to clarify the total levels, spatial changes, and health risks for Pb contamination in soils at local and national scales. The results show that Pb contents in surface soils at 58 Pb/Zn smelting sites in China ranged from 7 to 312,452 mg kg(-1) with an arithmetic average, geometric average, and median of 1982, 404, and 428 mg kg(-1), respectively (n = 1011). Surface soil Pb content at these smelting sites decreased from an average of 2466 to 659 mg kg(-1), then to 463 mg kg(-1) as the distance from the smelters increased from 2000 m. With respect to variation with depth, the average soil Pb content at these sites gradually decreased from 986 mg kg(-1) at 0- to 20-cm depth to 144 mg kg(-1) at 80- to 100-cm depth. Approximately 78 % of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites were classified as having high Pb pollution levels. Approximately 34.2 and 7.7 % of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites might pose adverse health effects and high chronic risks to children, respectively. The Pb/Zn smelting sites in the southwest and southeast provinces of China, as well as Liaoning province, were most contaminated and thus should receive priority for remediation.

Impact of model uncertainty on soil quality standards for cadmium in rice paddy fields

Energy Technology Data Exchange (ETDEWEB)

Roemkens, P.F.A.M., E-mail: paul.romkens@wur.nl [Soil Science Center, Alterra, WageningenUR. P.O. Box 47, 6700AA Wageningen (Netherlands); Brus, D.J. [Soil Science Center, Alterra, WageningenUR. P.O. Box 47, 6700AA Wageningen (Netherlands); Guo, H.Y.; Chu, C.L.; Chiang, C.M. [Taiwan Agricultural Research Institute (TARI), Wufong, Taiwan (China); Koopmans, G.F. [Soil Science Center, Alterra, WageningenUR. P.O. Box 47, 6700AA Wageningen (Netherlands); Department of Soil Quality, Wageningen University, WageningenUR. P.O. Box 47, 6700AA, Wageningen (Netherlands)

2011-08-01

At present, soil quality standards used for agriculture do not consider the influence of pH and CEC on the uptake of pollutants by crops. A database with 750 selected paired samples of cadmium (Cd) in soil and paddy rice was used to calibrate soil to plant transfer models using the soil metal content, pH, and CEC or soil Cd and Zn extracted by 0.01 M CaCl{sub 2} as explanatory variables. The models were validated against a set of 2300 data points not used in the calibration. These models were then used inversely to derive soil quality standards for Japonica and Indica rice cultivars based on the food quality standards for rice. To account for model uncertainty, strict soil quality standards were derived considering a maximum probability that rice exceeds the food quality standard equal to 10 or 5%. Model derived soil standards based on Aqua Regia ranged from less than 0.3 mg kg{sup -1} for Indica at pH 4.5 to more than 6 mg kg{sup -1} for Japonica-type cultivars in clay soils at pH 7. Based on the CaCl{sub 2} extract, standards ranged from 0.03 mg kg{sup -1} Cd for Indica cultivars to 0.1 mg kg{sup -1} Cd for Japonica cultivars. For both Japonica and Indica-type cultivars, the soil quality standards must be reduced by a factor of 2 to 3 to obtain the strict standards. The strong impact of pH and CEC on soil quality standards implies that it is essential to correct for soil type when deriving national or local standards. Validation on the remaining 2300 samples indicated that both types of models were able to accurately predict (> 92%) whether rice grown on a specific soil will meet the food quality standard used in Taiwan. - Research highlights: {yields} Cadmium uptake by Japonica and Indica rice varieties depends on soil pH and CEC. {yields} Food safety based soil standards range from 0.3 (Indica) to 6 mg kg{sup -1} (Japonica). {yields} Model uncertainty leads to strict soil standards of less than 0.1 mg kg{sup -1} for Indica. {yields} Soil pH and CEC should be

Application of phytotoxicity data to a new Australian soil quality guideline framework for biosolids

International Nuclear Information System (INIS)

Heemsbergen, Diane A.; Warne, Michael St.J.; Broos, Kris; Bell, Mike; Nash, David; McLaughlin, Mike; Whatmuff, Mark; Barry, Glenn; Pritchard, Deb; Penney, Nancy

2009-01-01

To protect terrestrial ecosystems and humans from contaminants many countries and jurisdictions have developed soil quality guidelines (SQGs). This study proposes a new framework to derive SQGs and guidelines for amended soils and uses a case study based on phytotoxicity data of copper (Cu) and zinc (Zn) from field studies to illustrate how the framework could be applied. The proposed framework uses normalisation relationships to account for the effects of soil properties on toxicity data followed by a species sensitivity distribution (SSD) method to calculate a soil added contaminant limit (soil ACL) for a standard soil. The normalisation equations are then used to calculate soil ACLs for other soils. A soil amendment availability factor (SAAF) is then calculated as the toxicity and bioavailability of pure contaminants and contaminants in amendments can be different. The SAAF is used to modify soil ACLs to ACLs for amended soils. The framework was then used to calculate soil ACLs for copper (Cu) and zinc (Zn). For soils with pH of 4-8 and OC content of 1-6%, the ACLs range from 8 mg/kg to 970 mg/kg added Cu. The SAAF for Cu was pH dependant and varied from 1.44 at pH 4 to 2.15 at pH 8. For soils with pH of 4-8 and OC content of 1-6%, the ACLs for amended soils range from 11 mg/kg to 2080 mg/kg added Cu. For soils with pH of 4-8 and a CEC from 5-60, the ACLs for Zn ranged from 21 to 1470 mg/kg added Zn. A SAAF of one was used for Zn as it concentrations in plant tissue and soil to water partitioning showed no difference between biosolids and soluble Zn salt treatments, indicating that Zn from biosolids and Zn salts are equally bioavailable to plants

Potential for Phytoextraction of Cu by Sesamum indicum L. and Cyamopsis tetragonoloba L.: A Green Solution to Decontaminate Soil

Science.gov (United States)

Amin, Hira; Arain, Basir Ahmed; Abbasi, Muhammad Sadiq; Jahangir, Taj Muhammad; Amin, Farah

2018-05-01

Phytoextraction is a plant based-technique for removing toxic heavy metals from polluted soil. The experiment reported in this paper was undertaken to study the basic Cu phytoextraction potential of Sesamum indicum in comparison with Cyamopsis tetragonoloba for remediation of Cu contaminated soil in the framework of a pot-experiment. Plants were subjected to seven Cu concentrations (0, 25, 50, 100, 150, 200, and 300 mg kg-1 soil) for 12 weeks. The morphological (i.e. growth) and biochemical (i.e. chlorophyll) parameters of both the plant species were observed throughout the experimental period; the phytoextraction efficiency of S. indicum and C. tetragonoloba were also determined. Most growth parameters were reduced under high Cu stress. Our results shows that at low concentration (25 mg Cu kg-1) all the growth and biochemical parameters were increased but at elevated Cu concentrations, root length, shoot length, and biomass (fresh and dry) were all significantly decreased ( p soil was noted for all tested treatments. In this study, both plant species showed quite high Cu tolerance and accumulation efficiency, even though C. tetragonoloba have higher Cu accumulation and tolerance indices than that of S . indicum. At 300 mg Cu kg-1, the highest Cu concentration was found in the root (282.08 mg Cu kg-1) followed by leaf (105.78 mg Cu kg-1), stem (65.30 mg Cu kg-1), and pod (8.13 mg Cu kg-1) of S. indicum. In contrast, C. tetragonoloba had highest Cu concentration primarily in the root (158.45 mg Cu kg-1) followed by the stem (154.73 mg Cu kg-1), leaf (152.32 mg Cu kg-1), and pod (8.13 mg Cu kg-1). Considering rapid growth, high biomass, tolerance, accumulation efficiency, bioconcentration factor (BCF) > 1, bioaccumulation coefficient (BAC) > 1 and translocation factor (TF) > 1 established C. tetragonoloba as a potential candidate plant for the decontamination of slightly Cu-polluted soil where the growth of plants would not be impaired and the extraction of Cu could

The remediation of the lead-polluted garden soil by natural zeolite.

Science.gov (United States)

Li, Hua; Shi, Wei-yu; Shao, Hong-bo; Shao, Ming-an

2009-09-30

The current study investigated the remediation effect of lead-polluted garden soil by natural zeolite in terms of soil properties, Pb fraction of sequential extraction in soil and distribution of Pb in different parts of rape. Natural zeolite was added to artificially polluted garden soil to immobilize and limit the uptake of lead by rape through changing soil physical and chemical properties in the pot experiment under greenhouse conditions. Results indicated that the addition of natural zeolite could increase soil pH, CEC, content of soil organic matter and promote formation of soil aggregate. The application of zeolite decreased the available fraction of Pb in the garden soil by adjusting soil pH rather than CEC, and restrained the Pb uptake by rape. Data obtained suggested that the application of a dose of zeolite was adequate (>or=10 g kg(-1)) to reduce soluble lead significantly, even if lead pollution is severe in garden soil (>or=1000 mg kg(-1)). An appropriate dose of zeolite (20 g kg(-1)) could reduce the Pb concentration in the edible part (shoots) of rape up to 30% of Pb in the seriously polluted soil (2000 mg kg(-1)).

Treatment of chromium contaminated soil using bioremediation

Science.gov (United States)

Purwanti, Ipung Fitri; Putri, Tesya Paramita; Kurniawan, Setyo Budi

2017-11-01

Chromium contamination in soil occurs due to the disposal of chromium industrial wastewater or sludge that excess the quality standard. Chromium concentration in soil is ranged between 1 to 300 mg/kg while the maximum health standard is 2.5 mg/kg. Bioremediation is one of technology that could be used for remediating heavy metal contamination in soil. Bacteria have an ability to remove heavy metal from soil. One bacteria species that capable to remove chromium from soil is Bacillus subtilis. The aim of this research was to know the chromium removal percentage in contaminated soil by Bacillus subtilis. Artificial chromium contaminated soil was used by mixing 425gram sand and chromium trichloride solution. Concentration of chromium added into the spiked soil were 50, 75, and 100 mg/L. During 14 days, pH, soil temperature and soil moisture were tested. Initial and final number of bacterial colony and chromium concentration analysed. The result showed that the highest percentage of chromium removal was 11% at a chromium concentration of 75 mg/L

Lead Concentration in Primary School Soil-Dust in Nigeria, Africa

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Ekwumemgbo P. A.

2013-04-01

Full Text Available Lead in soil has been recognized as a public health problem, particularly among children. In recent years, attention has been directed to cumulative adverse effects of lead at low levels of intake. Leadcontaminated soil and dust have been identified as important contributors to blood lead levels. This work examines the total concentration of lead in primary school soil-dust in Nigeria. Soil-dusts were collected randomly from six geopolitical areas of Nigeria, digested and analysed for total lead concentration by Atomic Absorption Spectrophotometry. The mean lead concentration in the dry season for the North East (NE, North West (NW, North Central (NC, South South (SS, South East (SE, South West (SW were 131.60 ± 70.98 mg/kg, 108.04 ± 47.33 mg/kg, 72.94 ± 55.45 mg/kg, 66.14 ± 43.9 mg/kg, 45.98 ± 34.60 mg/kg and 67.98 ± 34.89 mg/kg respectively. In the raining season the mean lead concentration were 130.78 ± 70.80 mg/kg, 106.24 ± 47.02 mg/kg, 70.96 ± 55.52 mg/kg, 64.12 ± 48.00 mg/kg, 44.58 ± 28.90 mg/kg, and 66.26 ± 41.87 mg/kg respectively. This analysis is necessary to provide scientific data base for the loading of lead in classroom soil-dust in each zone. The authors recommend measurement and surveillance of lead blood level of the primary school children and a clean-up of both classrooms and the school environment.

Phyto stabilization of cadmium contaminated soils by Lupinus uncinatus Schldl

International Nuclear Information System (INIS)

Ehsan, M.; Santamaria-Delgado, K.; Vazquez-Alarcon, A.; Alderete-Chavez, A.; Cruz de la, N.; Jaen-Contreras, D.; Augustine Molumeli, P.

2009-01-01

Phyto remediation offers the benefits of being in situ, low cost and environmentally sustainable. Lupinus species is starting to generate interest for phyto remediation of soils showing intermediate metal pollution. The aim of this study was to explore the accumulating behavior and tolerance of Lupinus uncessant Schldl. towards increasing Cd concentrations in soil. For this purpose the effects of different Cd treatments on plant growth, survival, metal tolerance, Cd accumulation and distribution in various plant organs were investigated. An 18 week pot trial was performed under greenhouse conditions. Cd was added as CdCl 2 .2 1 /2H 2 O at the rate of 0, 3, 6 and 9 mg Cd kg - 1 soil at three different occasions (after 4th, 12th and 15th week of plant growth) with four replicates. The Cd treatments applied, thus, were 9, 18 and 27 mg kg - 1. Cd inhibited plant height and number of leaves and induced a significant change in dry matter yield of roots, stems and leaves. Metal tolerance indices of 88, 82 and 49% were obtained for 9, 18 and 27 mg Cd kg - 1 treatments. The maximal shoot Cd concentration (stem+leaves) of 540 mg Cd kg - 1 dry matter was found at 27 mg Cd kg - 1 treatment. The poor translocation of Cd from roots to shoot was evident from shoot:root ratios <1. The present work is the first report about the growth performance of L. uncinatus under Cd stress, its degree of tolerance and pattern of Cd accumulation in response to varying Cd treatments in soil suggesting the use of L. uncinatus for phyto stabilization and revegetation of Cd polluted soils. (Author)

Effects of Applying Lime and CalciumMontmorillonite on Nitrification Dynamics in Acidic Soil

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WANG Mei

2017-01-01

Full Text Available Soil acidification is known as a natural and slow process along with clay mineral weathering. In recent years however, with inten sive soil utilization in agriculture, soil acidification has increased dramatically and nitrification of ammonium nitrogen fertilizer is one of the main contributors to soil acidification. Lime application is the traditional practice to improve acidic soils but it often makes the soil acidic a gain leading to soil compaction in most cases. Montmorillonite is the main clay mineral component of alkaline or neutral soils, more so it is known to undergo further weathering processes during soil acidification. The laboratory-based incubations were used in this study, and nitri fication was measured while kinetic curves were fitted to check the effects of decreasing soil acidity by lime(Ca-OHand montmorillonite (Ca-Mon nitrification of the acidic soil. The results showed that significant nitrification was observed both in Ca-OH and Ca-M treatments, and the nitrification process was fitted in the first-order kinetic model, NNO3=N0+Np(1-exp(-k1t(P-1·d-1was significantly higher than that of Ca-M treatment(2.381 mg·kg-1·d-1. The potential nitrifi cation rate(Vpwere 6.42, 8.58 mg N·kg-1·d-1 at pH 5.7 and 6.2 respectively, and the average nitrification rate(Vaof Ca-OH treatment were 2.71, 3.88 mg N·kg-1·d-1 respectively, which were significantly greater than those of Ca-M treatment(Vp were 3.40, 4.56 mg N·kg-1·d-1 and Va were 2.36, 3.04 mg N·kg-1·d-1 at pH 5.7 and 6.2 respectively. Therefore the net nitrification rate, potential nitrification rate(Vp and average nitrification rate(Vaof Ca-OH treatment were significantly higher than that of Ca-M treatment, suggesting that the possibili ty and degree of soil reacidification by using lime to improve acidic soil is greater than using calcium montmorillonite. This study will provide a new reference for the improvement of acid soils.

Study on remediation for uranium contaminated soils enhanced by chelator using brassica mustard

International Nuclear Information System (INIS)

Wan Qinfang; Pan Ning; Jin Yongdong; Xia Chuanqin

2012-01-01

Screening of perfect hyperaccumulators is the key to the application of this technology. Through the previous stage study, mustard was found to be good at absorption and accumulation of uranium among 51 species, the plant grows fast with wide adaptability and large biomass. Researches will focus on the following two aspects: 1. Simulating U- contaminated soils was prepared by two different ways to add uranium. (1). UO 2 (NO 3 ) 2 . 6H 2 O solution was sprayed into soil when the plant was grown in the soil; (2). Above U-contaminated soils after planting and placed for a year. Study on whether the way of adding uranium can effect mustard accumulate uranium. Results found: in the first Phytoremediation, U-contaminated concentration at 100 mg/kg, U concentration in shoots reaches 1103.42 mg/kg, roots reach 1909.49 mg/kg, annual removal rate is 7.81%; in the second Phytoremediation, U-contaminated concentration at 100 mg/kg, U concentration in shoots reach 295.83 mg/kg, roots reach 268.42 mg/kg, annual removal rate is 2.52%. Led to the difference between the twice remediation is the speciation of uranium m soils has changed, respectively, Tessier-five step continuous extraction method for determination of uranium speciation in soils and found available uranium (exchangeable uranium, uranium carbonate) in the soil of the first phytoremediation was 52% higher than the second phytoremediation. 2. Study on chelators (Citric acids, Malic acids) and soil amendments (Organic fertilizer, microbe fertilizer. Humic acid organic fertilizer, Urea) whether effect mustard accumulate uranium, found organic fertilizer can reduce shoots accumulate uranium, Citric acid and microbe fertilizer increase shoots enrichment of uranium. (authors)

Effect of two major N-nitroso hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on earthworm reproductive success

International Nuclear Information System (INIS)

Zhang Baohong; Cox, Stephen B.; McMurry, Scott T.; Jackson, W. Andrew; Cobb, George P.; Anderson, Todd A.

2008-01-01

Soil and topical tests were employed to investigate the effect of two N-nitroso metabolites of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) on earthworm reproduction. The lowest observed effect concentration (LOEC) for cocoon production and hatching was 50 mg/kg for both hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX) in soil. MNX and TNX also significantly affected cocoon hatching in soil (p 20 values for MNX were 8.7 and 8.8 mg/kg for cocoon and juvenile production, respectively, compared to 9.2 and 9.1 mg/kg for TNX, respectively. The EC 20 values for the total number of cocoon hatchlings were 3.1 and 4.7 mg/kg for MNX and TNX, respectively, in soil and 4.5 and 3.1 mg/L in the topical test. Both MNX and TNX inhibited cocoon production and hatching, suggesting that they may have a negative affect on soil ecosystems at contaminated sites. - RDX metabolites affect earthworm cocoon production and hatching

Zinc accumulation in plant species indigenous to a Portuguese polluted site: relation with soil contamination.

Science.gov (United States)

Marques, Ana P G C; Rangel, António O S S; Castro, Paula M L

2007-01-01

The levels of zinc accumulated by roots, stems, and leaves of two plant species, Rubus ulmifolius and Phragmites australis, indigenous to the banks of a stream in a Portuguese contaminated site were investigated in field conditions. R. ulmifolius, a plant for which studies on phytoremediation potential are scarce, dominated on the right side of the stream, while P. australis proliferated on the other bank. Heterogeneous Zn concentrations were found along the banks of the stream. Zn accumulation in both species occurred mainly in the roots, with poor translocation to the aboveground sections. R. ulmifolius presented Zn levels in the roots ranging from 142 to 563 mg kg(-1), in the stems from 35 to 110 mg kg(-1), and in the leaves from 45 to 91 mg kg(-1), vs. average soil total Zn concentrations varying from 526 to 957 mg kg(-1). P. australis showed Zn concentrations in the roots from 39 to 130 mg kg(-1), in the stems from 31 to 63 mg kg(-1), and in the leaves from 37 to 83 mg kg(-1), for the lower average soil total Zn levels of 138 to 452 mg kg(-1) found on the banks where they proliferated. Positive correlations were found between the soil total, available and extractable Zn fractions, and metal accumulation in the roots and leaves of R. ulmifolius and in the roots and stems of P. australis. The use of R. ulmifolius and P. australis for phytoextraction purposes does not appear as an effective method of metal removing, but these native metal tolerant plant species may be used to reduce the effects of soil contamination, avoiding further Zn transfer to other environmental compartments.

Evaluation of Heavy Metal Exposure to Soil and Paddy Plant around the Closed Municipal Solid Waste Landfill: Case Study at Gunung Tugel Landfill, Banyumas-Central Java

Science.gov (United States)

Kasam; Rahmawati, Suphia; Mulya Iresha, Fajri; Wacano, Dhandhun; Farida Fauziah, Ida; Afif Amrullah, Muhammad

2018-01-01

This work was focused on assessing the exposure of heavy metal from closed municipal solid waste (MSW) landfill on soil and paddy plants. This study aimed to determine heavy metal content whether at the soil in the around Gunung Tugel landfill included and accumulated in the paddy plant tissues. The investigated metals include chromium (Cr), copper (Cu), cadmium (Cd), iron (Fe), and zinc (Zn). The samples were acid-digested before the desired elements were measured using Atomic Absorption Spectrophotometry (AAS). The results are presented as distribution map of the landfill area based on the total heavy metals content distribution in the soil and paddy plants. The samples shown that the concentrations of heavy metals around Gunung Tugel landfill are 6.27-34.71 mg/kg, 0.17-0.42 mg/kg, 28.29-48.69 mg/kg, 18,997.26-32,572.29 mg/kg, 342.74-834.49 mg/kg, 136.10-290.14 mg/kg at the top soil and 0.00-1.70 mg/kg, 0.00-0.26 mg/kg, 0.79-10.46 mg/kg, 13.88-61.46 mg/kg, 18.79-50.56 mg/kg, 87.27-273.22 mg/kg at the paddy for Cr, Cd, Cu, Fe, Mn, and Zn respectively. According to the results, The Gunung Tugel landfill is not a direct source of heavy metal pollution at paddy plant in the landfill area, but through surface water and soil media. Rainfall around landfill is quite high ie more 2000 mm/year of rainfall and soil permeability is 1.0 cm/sec.

Nitrogen transformations and greenhouse gas emissions from a riparian wetland soil: An undisturbed soil column study

Energy Technology Data Exchange (ETDEWEB)

Munoz-Leoz, Borja [Department of Chemical and Environmental Engineering, University of the Basque Country, UPV/EHU, E-48013 Bilbao (Spain); Antigueedad, Inaki [Department of Geodynamic, University of the Basque Country, UPV/EHU, E-48940 Leioa (Spain); Garbisu, Carlos [Department of Ecosystems, NEIKER-Tecnalia, E-48160 Derio (Spain); Ruiz-Romera, Estilita, E-mail: estilita.ruiz@ehu.es [Department of Chemical and Environmental Engineering, University of the Basque Country, UPV/EHU, E-48013 Bilbao (Spain)

2011-01-15

Riparian wetlands bordering intensively managed agricultural fields can act as biological filters that retain and transform agrochemicals such as nitrate and pesticides. Nitrate removal in wetlands has usually been attributed to denitrification processes which in turn imply the production of greenhouse gases (CO{sub 2} and N{sub 2}O). Denitrification processes were studied in the Salburua wetland (northern Spain) by using undisturbed soil columns which were subsequently divided into three sections corresponding to A-, Bg- and B2g-soil horizons. Soil horizons were subjected to leaching with a 200 mg NO{sub 3}{sup -} L{sup -1} solution (rate: 90 mL day{sup -1}) for 125 days at two different temperatures (10 and 20 {sup o}C), using a new experimental design for leaching assays which enabled not only to evaluate leachate composition but also to measure gas emissions during the leaching process. Column leachate samples were analyzed for NO{sub 3}{sup -} concentration, NH{sub 4}{sup +} concentration, and dissolved organic carbon. Emissions of greenhouse gases (CO{sub 2} and N{sub 2}O) were determined in the undisturbed soil columns. The A horizon at 20 {sup o}C showed the highest rates of NO{sub 3}{sup -} removal (1.56 mg N-NO{sub 3}{sup -} kg{sup -1} DW soil day{sup -1}) and CO{sub 2} and N{sub 2}O production (5.89 mg CO{sub 2} kg{sup -1} DW soil day{sup -1} and 55.71 {mu}g N-N{sub 2}O kg{sup -1} DW soil day{sup -1}). For the Salburua wetland riparian soil, we estimated a potential nitrate removal capacity of 1012 kg N-NO{sub 3}{sup -} ha{sup -1} year{sup -1}, and potential greenhouse gas emissions of 5620 kg CO{sub 2} ha{sup -1} year{sup -1} and 240 kg N-N{sub 2}O ha{sup -1} year{sup -1}. - Research Highlights: {yields}A new experimental design is proposed for leaching assays to simulate nitrogen transformations in riparian wetland soil. {yields}Denitrification is the main process responsible for nitrate removal in the riparian zone of Salburua wetland. {yields

Phytoremediation of fuel oil and lead co-contaminated soil by Chromolaena odorata in association with Micrococcus luteus.

Science.gov (United States)

Jampasri, Kongkeat; Pokethitiyook, Prayad; Kruatrachue, Maleeya; Ounjai, Puey; Kumsopa, Acharaporn

2016-10-02

Phytoremediation is widely promoted as a cost-effective technology for treating heavy metal and total petroleum hydrocarbon (TPH) co-contaminated soil. This study investigated the concurrent removal of TPHs and Pb in co-contaminated soil (27,000 mg kg(-1) TPHs, 780 mg kg(-1) Pb) by growing Siam weed (Chromolaena odorata) in a pot experiment for 90 days. There were four treatments: co-contaminated soil; co-contaminated soil with C. odorata only; co-contaminated soil with C. odorata and Micrococcus luteus inoculum; and co-contaminated soil with M. luteus only. C. odorata survived and grew well in the co-contaminated soil. C. odorata with M. luteus showed the highest Pb accumulation (513.7 mg kg(-1)) and uptake (7.7 mg plant(-1)), and the highest reduction percentage of TPHs (52.2%). The higher TPH degradation in vegetated soils indicated the interaction between the rhizosphere microorganisms and plants. The results suggested that C. odorata together with M. luteus and other rhizosphere microorganisms is a promising candidate for the removal of Pb and TPHs in co-contaminated soils.

Soil respiration in tropical seasonal rain forest in Xishuangbanna, SW China

Institute of Scientific and Technical Information of China (English)

SHA; Liqing; ZHENG; Zheng; TANG; Jianwei; WANG; Yinghong

2005-01-01

With the static opaque chamber and gas chromatography technique, from January 2003 to January 2004 soil respiration was investigated in a tropical seasonal rain forest in Xishuangbanna, SW China. In this study three treatments were applied, each with three replicates: A (bare soil), B (soil+litter), and C (soil+litter+seedling). The results showed that soil respiration varied seasonally, low from December 2003 to February 2004, and high from June to July 2004. The annual average values of CO2 efflux from soil respiration differed among the treatments at 1% level, with the rank of C (14642 mgCO2· m-2. h-1)＞B (12807 mgCO2· m-2. h-1)＞A (9532 mgCO2· m-2. h-1). Diurnal variation in soil respiration was not apparent due to little diurnal temperate change in Xishuangbanna. There was a parabola relationship between soil respiration and soil moisture at 1% level. Soil respiration rates were higher when soil moisture ranged from 35% to 45%. There was an exponential relationship between soil respiration and soil temperature (at a depth of 5cm in mineral soil) at 1% level. The calculated Q1o values in this study,ranging from 2.03 to 2.36, were very near to those of tropical soil reported. The CO2 efflux in 2003was 5.34 kgCO2· m-2. a-1 from soil plus litter plus seedling, of them 3.48 kgCO2· m-2. a-1 from soil (accounting for 62.5%), 1.19 kgCO2· m-2. a-1 from litter (22.3%) and 0.67 kgCO2·m-2. a-1 from seedling (12.5%).

Multi-criteria analysis of soil pollution by heavy metals in the vicinity of the Copper Smelting Plant in Bor (Serbia

Directory of Open Access Journals (Sweden)

NEVENKA PETROVIĆ

2011-04-01

Full Text Available This study highlights the consequences on soil pollution of one hund­red years of manufacturing in the Copper Mining and Smelting Complex RTB-Bor (Serbia. Soil sediments were taken via a probe from the surface layer of the soil at twelve different measuring points. The measuring points were all within 20 km of the smelting plant, which included both urban and rural zones. Soil sampling was performed using a soil core sampler in such way that a core of a soil of radius 5 cm and depth of 30 cm was removed. Subsequently, the samples were analyzed for pH and heavy metal concentrations (Cu, Pb, As, Cd, Mn, Ni and Hg using different spectrometric methods. The obtained results for the heavy metal contents in the samples show high values: 2,540 mg kg-1 Cu; 230 mg kg-1 Pb; 6 mg kg-1 Cd; 530 mg kg-1 Ni; 1,300 mg kg-1 Mn; 260 mg kg-1 As and 0.3 mg kg-1 Hg. In this study, critical zones of polluted soil were iden­tified and ranked according to their metal contents by the multi-criteria deci­sion method Preference Organization Method for Enrichment Evaluation/Geo­metrical Analysis for Interactive Assistance – PROMETHEE/GAIA, which is the preferred multivariate method commonly used in chemometric studies. The ranking results clearly showed that the most polluted zones are at locations holding the vital functions of the town. Therefore, due to the high bioavail­abi­lity of heavy metals through com­plex reactions with organic species in the sediments, consequences for human health could drastically emerge if these metals enter the food chain.

Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process.

Science.gov (United States)

Dias-Ferreira, Celia; Kirkelund, Gunvor M; Ottosen, Lisbeth M

2015-01-01

Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm(-2)), concentration of enhancing agent (0.25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm(-2) did not increase removal and thus using too high current densities can be a waste of energy. Desorption rate is important and both remediation time and ammonium citrate concentration are relevant parameters. It was possible to collect soil solution samples following an adaptation of the experimental set-up to ensure continuous supply of ammonium citrate to the soil in order to keep it saturated during the remediation. Monitoring soil solution gives valuable information on the evolution of remediation and helps deciding when the soil is remediated. Final concentrations in the soil ranged from 220 to 360 mg Cu kg(-1) (removals: 78-86%) and 440-590 mg Cr kg(-1) (removals: 35-51%), being within the 500 mg kg(-1) limit for a clean soil only for Cu. While further optimization is still required for Cr, the removal percentages are the highest achieved so far, for a real Cu and Cr-contaminated, calcareous soil. The results highlight EDR potential to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lead, Zn, and Cd in slags, stream sediments, and soils in an abandoned Zn smelting region, southwest of China, and Pb and S isotopes as source tracers

Energy Technology Data Exchange (ETDEWEB)

Yang, Yuangen; Li, Sun; Bi, Xiangyang; Wu, Pan; Liu, Taozhe; Li, Feili; Liu, Congqiang [Chinese Academy of Sciences, Guiyang City (China). Inst. of Geochemistry

2010-12-15

Smelting activity produced tons of slags with large quantities of highly toxic metals, resulting in contamination in adjacent soils and sediments as well. This study investigated the fractionation and sources of metals Pb, Zn, and Cd in polluted soils and sediments in a region with once prosperous Zn smelting activities in southwestern China. Soils with varying land uses were of a special concern due to their connection to the food chain. Obtained data would offer a valuable reference to the development of land-use management strategy in this region. In total, 130 soils and 22 stream sediments were sampled in the studied region. After air-dried and passed through a 2 mm sieve, soils and sediments were subjected to a three-step sequential extraction for the fractionation of Pb, Zn, and Cd. Besides, 66 slags were sampled, and acid-digested for the determination of total Pb, Zn, and Cd. Soils/sediments with extremely high Pb, Zn, and Cd concentrations were selected for observation and analysis using a scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. Stable lead and sulphur isotope techniques were applied for source tracing of metals in soils and sediments. Data were pooled for analysis of variance together with a post-hoc multiple comparison procedure. High concentrations of Pb ({proportional_to}46,219 mg kg{sup -1} with medians of 846 mg kg{sup -1} in soil, 7,415 mg kg{sup -1} in sediment, and 8,543 mg kg{sup -1} in slag), Zn ({proportional_to}57, 178 mg kg{sup -1} with medians of 1,085 mg kg{sup -1} in soil, 15,678 mg kg{sup -1} in sediment, and 14,548 mg kg{sup -1} in slag), and Cd ({proportional_to}312 mg kg{sup -1} with medians of 29.6 mg kg{sup -1} in soil, 47.1 mg kg{sup -1} in sediment, and 47.9 mg kg{sup -1} in slag) were measured. Soils with no cultivation had greater concentrations of Pb (16,686 mg kg{sup -1} in median), Zn (13,587 mg kg{sup -1} in median), and Cd (44.1 mg kg{sup -1} in median) than those with cultivation. Al

Heavy metal contamination of arable soil and corn plant in the vicinity of a zinc smelting factory and stabilization by liming.

Science.gov (United States)

Hong, Chang Oh; Gutierrez, Jessie; Yun, Sung Wook; Lee, Yong Bok; Yu, Chan; Kim, Pil Joo

2009-02-01

The heavy metal contamination in soils and cultivated corn plants affected by zinc smelting activities in the vicinity of a zinc smelting factory in Korea was studied. Soils and corn plants were sampled at the harvesting stage and analyzed for cadmium (Cd) and zinc (Zn) concentration, as well as Cd and Zn fraction and other chemical properties of soils. Cd and Zn were highly accumulated in the surface soils (0-20 cm), at levels higher than the Korean warning criteria (Cd, 1.5; Zn, 300 mg kg(-1)), with corresponding mean values of 1.7 and 407 mg kg(-1), respectively, but these metals decreased significantly with increasing soil depth and distance from the factory, implying that contaminants may come from the factory through aerosol dynamics (Hong et al., Kor J Environ Agr 26(3):204-209, 2007a; Environ Contam Toxicol 52:496-502, 2007b) and not from geological sources. The leaf part had higher Cd and Zn concentrations, with values of 9.5 and 1733 mg kg(-1), compared to the stem (1.6 and 547 mg kg(-1)) and grain (0.18 and 61 mg kg(-1)) parts, respectively. Cd and Zn were higher in the oxidizable fraction, at 38.5% and 46.9% of the total Cd (2.6 mg kg(-1)) and Zn (407 mg kg(-1)), but the exchangeable + acidic fraction of Cd and Zn as the bioavailable phases was low, 0.2 and 50 mg kg(-1), respectively. To study the reduction of plant Cd and Zn uptake by liming, radish (Raphanus sativa L.) was cultivated in one representative field among the sites investigated, and Ca(OH)(2) was applied at rates of 0, 2, 4, and 8 mg ha(-1). Plant Cd and Zn concentrations and NH(4)OAc extractable Cd and Zn concentrations of soil decreased significantly with increasing Ca(OH)(2) rate, since it markedly increases the cation exchange capacity of soil induced by increased pH. As a result, liming in this kind of soil could be an effective countermeasure in reducing the phytoextractability of Cd and Zn.

Development of Ecological Toxicity and Biomagnification Data for Explosives Contaminants in Soil

Science.gov (United States)

2003-07-01

could develop at 500 mg kg-1 TNT in soil. Winfield et al. (1999) found that sunflower and sanfroin were the most sensitive species among ten species...up to 4000 mg kg-1 soil) during early life stage resulted in adverse responses in sensitive terrestrial plants such as sunflower and sanfroin. Bean...plants (Harvey et al., 1991; Best et al., 1999; Groom et al., 2002). Therefore, phytoremediation is a potential route for removing these EMs from soil

Comparative assessment of soil contamination by lead and heavy metals in riparian and agricultural areas (southern Québec, Canada).

Science.gov (United States)

Saint-Laurent, Diane; Hähni, Marlies; St-Laurent, Julien; Baril, Francis

2010-08-01

Soils contaminated with hydrocarbons (C(10)-C(50)), PAHS, lead and other heavy metals were recently found in the banks of two major rivers in southern Québec. Alluvial soils are contaminated over a distance of 100 kilometers. Eight sampling sites, including some located in agriculture areas (farm woodlots) have been selected to compare air pollution (aerosol fallout and rainout) and river pollution values. The concentrations detected in soil profiles for As, Cd and Pb vary between 3.01 to 37.88 mg kg(-1) (As), 0.11 to 0.81 mg kg(-1) (Cd) 12.32 to 149.13 mg kg(-1) (Pb). These metallic elements are considered highly toxic and can harm wildlife and human health at high levels. The maximum concentration of Pb (149.13 mg kg(-1)) in soils of the riparian zone is twelve times higher than the average Pb concentration found in a natural state evaluated at 15.3 mg kg(-1) (SD 17.5). Pb concentrations in soils of agricultural areas (woodland control sites) range between 12 and 22 mg kg(-1), and given that these values are recorded in surrounding cultivated land, the issue of the quality of agricultural products (crops and forage) to feed livestock or destined for human consumption must be further addressed in detail.

[Effects of soil properties on the stabilization process of cadmium in Cd alone and Cd-Pb contaminated soils].

Science.gov (United States)

Wu, Man; Xu, Ming-Gang; Zhang, Wen-Ju; Wu, Hai-Wen

2012-07-01

In order to clarify the effects of soil properties on the stabilization process of the cadmium (Cd) added, 11 different soils were collected and incubated under a moisture content of 65%-70% at 25 degrees C. The changes of available Cd contents with incubation time (in 360 days) in Cd and Cd-Pb contaminated treatments were determined. The stabilization process was simulated using dynamic equations. The results showed that after 1.0 mg x kg(-1) Cd or 500 mg x kg(-1) Pb + 1.0 mg x kg(-1) Cd were added into the soil, the available Cd content decreased rapidly during the first 15 days, and then the decreasing rate slowed down, with an equilibrium content reached after 60 days' incubation. In Cd-Pb contaminated soils, the presence of Pb increased the content of available Cd. The stabilization process of Cd could be well described by the second-order equation and the first order exponential decay; meanwhile, dynamic parameters including equilibrium content and stabilization velocity were used to characterize the stabilization process of Cd. These two key dynamic parameters were significantly affected by soil properties. Correlation analysis and stepwise regression suggested that high pH and high cation exchange capacity (CEC) significantly retarded the availability of Cd. High pH had the paramount effect on the equilibrium content. The stabilization velocity of Cd was influenced by the soil texture. It took shorter time for Cd to get stabilized in sandy soil than in the clay.

Impact of rice-straw biochars amended soil on the biological Si cycle in soil-plant ecosystem

Science.gov (United States)

Li, Zimin; Delvaux, Bruno; Struyf, Eric; Unzué-Belmonte, Dácil; Ronsse, Frederik; Cornelis, Jean-Thomas

2017-04-01

Biochar used as soil amendment can enhance soil fertility and plant growth. It may also contribute to increase the plant mineralomass of silicon (Si). However, very little studies have focused on the plant Si cycling in biochar amended soils. Here, we study the impact of two contrasting biochars derived from rice straws on soil Si availability and plant Si uptake. Rice plants were grown in a hydroponic device using Yoshida nutrient solution, respectively devoid of H4SiO4 (0 ppm Si: Si-) and enriched with it (40 ppm Si: Si+). After 12 weeks, the plants were harvested for further pyrolysis, conducted with holding time of 1h at 500˚ C. The respective rice-biochars are Si-/biochar and Si+/biochar. They exhibit contrasting phytolith contents (0.3 g Si kg-1 vs. 51.3 g Si kg-1), but identical physico-chemical properties. They were applied in two soils differing in weathering stage: a weathered Cambisol (CA) and a highly weathered Nitisol (NI). We then studied the effects of the amended biochar on CaCl2 extractable Si using a 64-days kinetic approach, on the content of soil biogenic Si, and on the uptake of Si by wheat plants grown for 5 weeks. We also quantified Si mineralomass in plants. We compared the effects of biochars to that of wollastonite (Wo)-(CaSiO3), a common Si-fertilizer. Our results show that Si+/biochar significantly increase the content of BSi in both soils. In CA, the cumulative content of CaCl2 extractable Si amounts to 85 mg kg-1 after Si+/biochar amendment, which is below the amount extracted after Wo application (100 mg kg-1). In contrast, in NI, the cumulative content of CaCl2 extractable Si is 198 mg kg-1 in the Si+/biochar amended treatment, which is far above the one measured after Wo application (93 mg kg-1). The Si-/biochar has no effect on the cumulative content of CaCl2 extractable Si in either soil type. Biochars and wollastonite increase the biomass of wheat on both soils. The increase is, however, larger in NI than in CA. In terms of Si

Decreases in soil microbial function and functional diversity in response to depleted uranium

International Nuclear Information System (INIS)

Meyer, M.C.; Paschke, M.W.; McLendon, T.

1998-01-01

A soil microcosm experiment was used to analyze effects of depleted uranium (DU) on soil function, and the concomitant changes in bacterial functional diversity. Uranium treatment levels were 0, 50, 500, 5000, 10,000 and 25,000 mg DU kg -1 soil. Three measures of soil function were made. Overall soil biological activity was assessed via measurement of soil respiration. Decomposition was assessed by measurement of mass loss of four different plant litter types: wood sticks, cellulose paper, high-N grass, and low-N grass. Mineral N availability in the microcosms was estimated using ion-exchange resin bags. Functional diversity of the microcosms was analyzed through the use of the Biolog-system of sole-C-utilization patterns. Soil respiration was the most sensitive measure of functional changes, with significant decreases observed starting at the 500 mg kg -1 treatment. No differences in N availability were observed across the U treatments. Litter decomposition was significantly decreased at the 25,000 mg kg -1 level relative to the control for all litter types except the high-N grass. Wood decomposition was reduced by 84% at the 25,000 mg kg - treatment, cellulose paper by 68%, and low-N grass by 15%. Decreases in the functional diversity of the bacterial community were related to the observed decrease in soil respiration, and to the greater effect on decomposition of the lower-quality litter types

Assessment of chromium biostabilization in contaminated soils using standard leaching and sequential extraction techniques

International Nuclear Information System (INIS)

Papassiopi, Nymphodora; Kontoyianni, Athina; Vaxevanidou, Katerina; Xenidis, Anthimos

2009-01-01

The iron reducing microorganism Desulfuromonas palmitatis was evaluated as potential biostabilization agent for the remediation of chromate contaminated soils. D. palmitatis were used for the treatment of soil samples artificially contaminated with Cr(VI) at two levels, i.e. 200 and 500 mg kg -1 . The efficiency of the treatment was evaluated by applying several standard extraction techniques on the soil samples before and after treatment, such as the EN12457 standard leaching test, the US EPA 3060A alkaline digestion method and the BCR sequential extraction procedure. The water soluble chromium as evaluated with the EN leaching test, was found to decrease after the biostabilization treatment from 13 to less than 0.5 mg kg -1 and from 120 to 5.6 mg kg -1 for the soil samples contaminated with 200 and 500 mg Cr(VI) per kg soil respectively. The BCR sequential extraction scheme, although not providing accurate estimates about the initial chromium speciation in contaminated soils, proved to be a useful tool for monitoring the relative changes in element partitioning, as a consequence of the stabilization treatment. After bioreduction, the percentage of chromium retained in the two least soluble BCR fractions, i.e. the 'oxidizable' and 'residual' fractions, increased from 54 and 73% to more than 96% in both soils

Metal and metalloid accumulation in cultivated urban soils: A medium-term study of trends in Toronto, Canada.

Science.gov (United States)

Wiseman, Clare L S; Zereini, Fathi; Püttmann, Wilhelm

2015-12-15

This study aims to examine the elemental enrichment patterns in low to medium traffic areas over a three year period in Toronto, Canada. Soils were sampled at three locations with different volumes of traffic between 2010 and 2013. A range of elements, including V, Cr, Mn, Cu, Cd, As, Sb and Pb, were measured in acid digested samples using ICP-MS. While the concentrations of Cd, Sb and Pb were found to be relatively low, a significant, albeit small increase in their levels over time was determined for all sites. For the low traffic areas, median Cd, Sb and Pb concentrations increased from 0.18mg Cd/kg, 0.14mg Sb/kg and 12mg Pb/kg in 2010 to 0.38mg Cd/kg, 0.21mg Sb/kg and 15mg Pb/kg in 2012, respectively. For the medium traffic site, the respective levels of Cd and Sb rose from 0.19mg Cd/kg and 0.14mg Sb/kg in 2010 to 0.49mg Cd/kg and 0.28mg Sb/kg in 2012. Median Pb concentrations at the medium traffic site were comparable to those at the low traffic sites (13mg/kg in 2010 and 15mg/kg in 2012). Principal Component Analysis (PCA) revealed the existence of two components (rotated), which explained 77% of the variance for all sites: 1. PC1 with large loadings of V, Cr, Co and Cu that likely originate from the commercial soil originally used for monitoring purposes, and 2. PC2 with high correlations between Cd, Sb and Pb, attributed to traffic sources of emissions. The resuspension and transport of more mobile fractions of contaminated dust and soil particles is hypothesized to be contributing to an elemental enrichment of soils located in low traffic areas. Copyright © 2015 Elsevier B.V. All rights reserved.

Nitrogen cycling in a flooded-soil ecosystem planted to rice (Oryza sativa L.)

International Nuclear Information System (INIS)

Reddy, K.R.

1982-01-01

15 N studies of various aspects of the nitrogen cycle in a flooded rice ecosystem on Crowley silt loam soil in Louisiana were reviewed to construct a mass balance model of the nitrogen cycle for this system. Nitrogen transformations modeled included 1) net ammonification (0.22 mg NH 4+ -N kg dry soil - 1 day - 1 ). 2) net nitrification (207 mg NO 3- -N kg dry soil - 1 day - 1 ). 3) denitrification (0.37 mg N kg dry soil - 1 day - 1 ), and 4) biological N 2 fixation (0.16 mg N kg dry soil - 1 day - 1 ). Nitrogen inputs included 1) application of fertilizers, 2) incorporation of crop residues, 3) biological N 2 fixation, and 4) deposition. Nitrogen outputs included 1) crop removal, 2) gaseous losses from NH 3 volatilization and simultaneous occurrence of nitrification-denitrification, and 3) leaching and runoff. Mass balance calculations indicated that 33% of the available inorganic nitrogen was recovered by rice, and the remaining nitrogen was lost from the system. Losses of N due to ammonia volatilization were minimal because fertilizer-N was incorporated into the soil. A significant portion of inorganic-N was lost by ammonium diffusion from the anaerobic layer to the aerobic layer in response to a concentration gradient and subsequent nitrification in the aerobic layer followed by nitrate diffusion into the anaerobic layer and denitrification into gaseous end products. Leaching and surface runoff losses were minimal. (orig.)

Green manure addition to soil increases grain zinc concentration in bread wheat.

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Forough Aghili

Full Text Available Zinc (Zn deficiency is a major problem for many people living on wheat-based diets. Here, we explored whether addition of green manure of red clover and sunflower to a calcareous soil or inoculating a non-indigenous arbuscular mycorrhizal fungal (AMF strain may increase grain Zn concentration in bread wheat. For this purpose we performed a multifactorial pot experiment, in which the effects of two green manures (red clover, sunflower, ZnSO4 application, soil γ-irradiation (elimination of naturally occurring AMF, and AMF inoculation were tested. Both green manures were labeled with 65Zn radiotracer to record the Zn recoveries in the aboveground plant biomass. Application of ZnSO4 fertilizer increased grain Zn concentration from 20 to 39 mg Zn kg-1 and sole addition of green manure of sunflower to soil raised grain Zn concentration to 31 mg Zn kg-1. Adding the two together to soil increased grain Zn concentration even further to 54 mg Zn kg-1. Mixing green manure of sunflower to soil mobilized additional 48 µg Zn (kg soil-1 for transfer to the aboveground plant biomass, compared to the total of 132 µg Zn (kg soil-1 taken up from plain soil when neither green manure nor ZnSO4 were applied. Green manure amendments to soil also raised the DTPA-extractable Zn in soil. Inoculating a non-indigenous AMF did not increase plant Zn uptake. The study thus showed that organic matter amendments to soil can contribute to a better utilization of naturally stocked soil micronutrients, and thereby reduce any need for major external inputs.

Soil Phosphorus status in Chinese greenhouse vegetable production system

DEFF Research Database (Denmark)

Kianpoor Kalkhajeh, Yusef

-1 were found in the leachates from P rich coarse-textured Tongshan soils. In contrast, DRP leaching from fine-textured Guli soils rarely exceeded the suggested environmental P threshold of 0.1 mg L-1. In accordance, a change-point Olsen P value above 41 mg kg-1 led to susbtantial DRP leaching from...

Soil organic phosphorus in soils under different land use systems in northeast Germany

Science.gov (United States)

Slazak, Anna; Freese, Dirk; Hüttl, Reinhard F.

2010-05-01

Phosphorus (P) is commonly known as a major plant nutrient, which can act as a limiting factor for plant growth in many ecosystems, including different land use systems. Organic P (Po), transformations in soil are important in determining the overall biological availability of P and additionally Po depletion is caused by land cultivation. It is expected that changes of land use modifies the distribution of soil P among the various P-pools (Ptotal, Plabile, Po), where the Plabile forms are considered to be readily available to plants and Po plays an important role with P nutrition supply for plants. The aim of the study was to measure the different soil P pools under different land use systems. The study was carried out in northeast of Brandenburg in Germany. Different land use systems were studied: i) different in age pine-oak mixed forest stands, ii) silvopastoral land, iii) arable lands. Samples were taken from two mineral soil layers: 0-10 and 10-20 cm. Recently, a variety of analytical methods are available to determine specific Po compounds in soils. The different P forms in the soil were obtained by a sequential P fractionation by using acid and alkaline extractants, which mean that single samples were subjected to increasingly stronger extractants, consequently separating the soil P into fractions based on P solubility. The soil Ptotal for the forest stands ranged from 100 to 183 mg kg -1 whereas Po from 77 to 148 mg kg -1. The Po and Plabile in both soil layers increased significantly with increase of age-old oak trees. The most available-P fraction was Plabile predominate in the oldest pine-oak forest stand, accounting for 29% of soil Ptotal. For the silvopasture and arable study sites the Ptotal content was comparable. However, the highest value of Ptotal was measured in the 30 years old silvopastoral system with 685 mg kg-1 and 728 mg kg-1 at 0-10 cm and 10-20 cm depth, respectively than in arable lands. The results have shown that the 30 years old

Bioremediation of petroleum-contaminated soil

International Nuclear Information System (INIS)

Pearce, K.; Snyman, H.G.; Oellermann, R.A.; Gerber, A.

1995-01-01

A pilot-scale study was conducted to evaluate the application of land-farming techniques in bioremediating a soil highly contaminated with petroleum products. A commercial biosupplement, and one prepared with indigenous microorganisms from the contaminated soil, were tested. Application of either of the biosupplements, in addition to the control of pH, moisture, and oxygen levels, resulted in a 94% reduction of the initial total petroleum hydrocarbon concentration (TPHC) (32% mass/mass) over a 70-day period. Implementation of these findings at full scale to bioremediate highly weathered petroleum products showed an average reduction of 89% over 5.5 months. Target levels of 1,400 mg/kg soil were reached from an initial average TPHC concentration of 12,200 mg/kg soil

SoilGrids1km--global soil information based on automated mapping.

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Tomislav Hengl

Full Text Available BACKGROUND: Soils are widely recognized as a non-renewable natural resource and as biophysical carbon sinks. As such, there is a growing requirement for global soil information. Although several global soil information systems already exist, these tend to suffer from inconsistencies and limited spatial detail. METHODOLOGY/PRINCIPAL FINDINGS: We present SoilGrids1km--a global 3D soil information system at 1 km resolution--containing spatial predictions for a selection of soil properties (at six standard depths: soil organic carbon (g kg-1, soil pH, sand, silt and clay fractions (%, bulk density (kg m-3, cation-exchange capacity (cmol+/kg, coarse fragments (%, soil organic carbon stock (t ha-1, depth to bedrock (cm, World Reference Base soil groups, and USDA Soil Taxonomy suborders. Our predictions are based on global spatial prediction models which we fitted, per soil variable, using a compilation of major international soil profile databases (ca. 110,000 soil profiles, and a selection of ca. 75 global environmental covariates representing soil forming factors. Results of regression modeling indicate that the most useful covariates for modeling soils at the global scale are climatic and biomass indices (based on MODIS images, lithology, and taxonomic mapping units derived from conventional soil survey (Harmonized World Soil Database. Prediction accuracies assessed using 5-fold cross-validation were between 23-51%. CONCLUSIONS/SIGNIFICANCE: SoilGrids1km provide an initial set of examples of soil spatial data for input into global models at a resolution and consistency not previously available. Some of the main limitations of the current version of SoilGrids1km are: (1 weak relationships between soil properties/classes and explanatory variables due to scale mismatches, (2 difficulty to obtain covariates that capture soil forming factors, (3 low sampling density and spatial clustering of soil profile locations. However, as the SoilGrids system is

Heavy Metals (Mg, Mn, Ni and Sn contamination in Soil Samples of Ahvaz II Industrial Estate of Iran in 2013

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Soheil l Sobhanardakani

2016-04-01

Full Text Available Background & Aims of the Study: Due to the rapid industrial development in Khuzestan province of Iran during recent years, this study was performed to analyze the variation of metals concentrations (Mg, Mn, Ni, and Sn in soil samples of Ahvaz II Industrial estate during the spring season of 2013. Materials & Methods: In this experimental study, 27 topsoil samples were collected from nine stations. The intensity of the soil contamination was evaluated, using a contamination factor (Cf and geo-accumulation index (I-geo. Results:  The mean soil concentrations (in mg kg-1 (dry weight were in ranged within 870-1144 (Mg, 188-300 (Mn, 93-199 (Ni and 9-15 (Sn. The data indicated that the I-geo value for all metals falls in class ‘1’. Also the Cf value for Mg and Mn falls in class ‘0’, the Cf value for Sn falls in class ‘1’ and the Cf value for Ni falls in the classes of ‘1’ and ‘2’. The result of the Pearson correlation showed that there were significant positive associations between all metals. Conclusions: According to the results which were achieved by a cluster analysis, there were significant positive associations among all metals based on Pearson correlation coefficient, especially between Ni and Sn; also both of them with Mn. Because the Ni originates from oil sources it can be resulted that Mn and Sn originate from oil sources, too. Therefore, industrial activities and exploitation of oil reservoirs are the main cause of pollution in that area. Also, it can be concluded that, with increasing the distance from the source of pollution, the accumulation of contaminants in the soil samples decreased.

Phytoremediation of cadmium contaminated soils by tuberose

International Nuclear Information System (INIS)

Ramana, S.; Biswas, A.K.; Singh, A.B.; Ajay; Ahirwar, N.K.; Behera, S.K.; Subba Rao, A.; Naveen Kumar, P.

2012-01-01

The potential of three varieties of tuberose (Prajwal, Shringar and Mexican single) for phytoremediation of soil contaminated with cadmium was evaluated by subjecting the plants to five levels of Cd (0, 25, 50, 75 and 100 mg kg -1 soil). Applied Cd did not produce any toxic symptoms in all the three varieties of tuberose except marginal reduction in the photosynthesis rate and total dry weight beyond 50 mg Cd kg -1 soil. The study showed that tuberose possessed the typical ability of Cd hyper accumulator characterized by (1) accumulation of Cd in the shoots of the plant exceeding the critical judging standard i.e., 100 μg g -1 DW and (2) ratio of Cd in the shoots to bulbs >1. It was concluded that tuberose may be an effective accumulator plant for phytoremediation of cadmium polluted soils. (author)

Spatial Distribution of Heavy Metals and the Environmental Quality of Soil in the Northern Plateau of Spain by Geostatistical Methods.

Science.gov (United States)

Santos-Francés, Fernando; Martínez-Graña, Antonio; Zarza, Carmelo Ávila; Sánchez, Antonio García; Rojo, Pilar Alonso

2017-05-26

The environmental quality of soil in the central part of the Northern Plateau of Spain has been analyzed by studying the heavy metal content of 166 samples belonging to the horizons A, B and C of 89 soil profiles. The analysis to assess the environmental risk of heavy metals in the soil was carried out by means of the spatial distribution of nine heavy metals and the use of several pollution indices. The results showed that the concentration values of heavy metals (x ± S) in the superficial soil horizons were the following: With a total of 6.71 ± 3.51 mg kg -1, the contents of Cd is 0.08 ± 0.06 mg kg-1, Co is 6.49 ± 3.21 mg kg-1, Cu is 17.19 ± 10.69 mg kg-1, Cr is 18.68 ± 12.28 mg kg-1, Hg is 0.083 ± 0.063 mg kg-1, Ni is 12.05 ± 6.76 mg kg-1, Pb is 14.10 ± 11.32 mg kg-1 and Zn is 35.31 ± 14.63 mg kg-1. These nine metals exceed the values of the natural geological background level of Tertiary period sediments and rocks that form part of the Northern Plateau in Spain. Nemerow and Potential Ecological Risk indices were calculated, with the "improved" Nemerow index allowing pollution within the soil superficial horizons to be determined. The data obtained indicated that the majority of the soil (54.61%) showed low to moderate contamination, 22.31% showed moderate contamination and 21.54% of the samples were not contaminated. If we consider the Potential of Ecological Risk Index (RI), the largest percentage of soil samples showed low (70.79%) to moderate (25.38%) ecological risk of potential contamination, where the rest of the soil presented a considerable risk of contamination. The nine trace elements were divided into three principal components: PC1 (Cu, Cr, Ni, Co and Zn), PC2 (As and Hg) and PC3 (Cd). All metals accumulated in the soil came from parent rock, agricultural practices and the run-off of residual waters towards rivers and streams caused by industrial development and an increase in population density. Finally, cartography of the spatial

Effect of pH on boron adsorption in some soils of Paraná, Brazil

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Fábio Steiner

2013-06-01

Full Text Available Temporary B deficiency can be triggered by liming of acid soils because of increased B adsorption at higher soil pH. Plants respond directly to the activity of B in soil solution and only indirectly to B adsorbed on soil constituents. Because the range between deficient and toxic B concentration is relatively narrow, this poses difficulty in maintaining appropriate B levels in soil solution. Thus, knowledge of the chemical behavior of B in the soil is particularly important. The present study investigated the effect of soil pH on B adsorption in four soils of Paraná State, and to correlate these values with the physical and chemical properties of the soils. Surface samples were taken from a Rhodic Hapludox, Arenic Hapludalf, Arenic Hapludult, and one Typic Usthorthent. To evaluate the effect of pH on B adsorption, subsamples soil received the application of increasing rates of calcium carbonate. Boron adsorption was accomplished by shaking 2.0 g soil, for 24 h, with 20 mL of 0.01 mol L¹ NaCl solution containing different concentrations (0.0, 0.1, 0.2, 0.4, 0.8, 1.2, 1.6, 2.0, and 4.0 mg B L-1. Sorption was fitted to non-linear form of the Langmuir adsorption isotherm. Boron adsorption increased as concentration increased. Boron adsorption was dependent on soil pH, increasing as a function of pH in the range between 4.6 and 7.4, although the bonding energy has decreased. Maximum adsorption capacity (MAC of B was observed in the Arenic Hapludalf (49.8 mg B kg-1 soil followed by Arenic Hapludult (22.5 mg kg-1, Rhodic Hapludox (17.4 mg kg-1, and Typic Usthorthent (7.0 mg kg-1. The organic matter content, clay content, and aluminum oxide content (Al2O3 were the soils properties that affecting the B adsorption on Paraná soils.

Loads Limits Values of Soils with Petroleum Hydrocarbons

Science.gov (United States)

Dumitru, Mihail; Vladimirescu, Andreea

2017-04-01

The high demand for oil and associated products as a source of energy, resulting in increased oil exploitation, producing, refining, transportation, storage, marketing and use led to high levels of environmental pollution. The optimum bioremediation variant proved to be the one in which fertilizer (potassium humate in NPK matrix with microelements and 8% monosaccharides) applied in a 650 l/ha dose was used together with the Zeba absorbent in 32 kg/ha dose, where the TPH level dropped by 58% in 45 days from the pollution with 3% crude oil. Most of these areas are affected by historical pollution. Many organic contaminants may undergo an ongoing process in the soil, whereby over time contaminant become less and less subject to decomposition even though relatively can still be detected in the laboratory analyses. In Romania about 50.000 ha are polluted with oil and/or brine. The bioremediation was the main method of rehabilitation. The Regulation on the assessment of environmental pollution, the following are presented as guide values for total oil hydrocarbons content in soil: - normal: less than 100 mg/kg; - alert values for sensitive soils: 200 mg/kg; - alert values for less sensitive soils: 1000 mg/kg; - intervention values for sensitive soils: 500 mg/kg; - intervention values for less sensitive soils: 2000 mg/kg. Researches done in laboratory monitored the effect of various concentrations of oil (under 2000 mg/kg, 3000 mg/kg, 5000 mg/kg, 7000 mg/kg, 10 000 mg/kg) on germination of wheat seeds at 5 and 7 days after seeding and (fresh and dry) biomass production after 40 days. Tree experiments were done: one with recently contaminated light oil, one with recently contaminated heavy oil and one with old contamination. After 5 days from sowing, the largest number of germinated seeds was found in the experiments with old contamination. The fewest germinated seeds was found in the experience with light oil. The experience with heavy oil showed an intermediate number of

Bioavailability and chronic toxicity of bismuth citrate to earthworm Eisenia andrei exposed to natural sandy soil.

Science.gov (United States)

Omouri, Zohra; Hawari, Jalal; Fournier, Michel; Robidoux, Pierre Yves

2018-01-01

The present study describes bioavailability and chronic effects of bismuth to earthworms Eisenia andrei using OECD reproduction test. Adult earthworms were exposed to natural sandy soil contaminated artificially by bismuth citrate. Average total concentrations of bismuth in soil recovered by HNO 3 digestion ranged from 75 to 289mg/kg. Results indicate that bismuth decreased significantly all reproduction parameters of Eisenia andrei at concentrations ≥ 116mg/kg. However, number of hatched cocoons and number of juveniles seem to be more sensitive than total number of cocoons, as determined by IC 50 ; i.e., 182, 123 and > 289mg/kg, respectively. Bismuth did not affect Eisenia andrei growth and survival, and had little effect on phagocytic efficiency of coelomocytes. The low immunotoxicity effect might be explained by the involvement of other mechanisms i.e. bismuth sequestered by metal-binding compounds. After 28 days of exposure bismuth concentrations in earthworms tissue increased with increasing bismuth concentrations in soil reaching a stationary state of 21.37mg/kg dry tissue for 243mg Bi/kg dry soil total content. Data indicate also that after 56 days of incubation the average fractions of bismuth available extracted by KNO 3 aqueous solution in soil without earthworms varied from 0.0051 to 0.0229mg/kg, while in soil with earthworms bismuth concentration ranged between 0.310-1.347mg/kg dry soil. We presume that mucus and chelating agents produced by earthworms and by soil or/and earthworm gut microorganisms could explain this enhancement, as well as the role of dermal and ingestion routes of earthworms uptake to soil contaminant. Copyright © 2017 Elsevier Inc. All rights reserved.

Accumulation and residue of napropamide in alfalfa (Medicago sativa) and soil involved in toxic response.

Science.gov (United States)

Cui, Li E; Yang, Hong

2011-06-15

Napropamide belongs to the amide herbicide family and widely used to control weeds in farmland. Intensive use of the herbicide has resulted in widespread contamination to ecosystems. The present study demonstrated an analysis on accumulation of the toxic pesticide napropamide in six genotypes of alfalfa (Medicago sativa), along with biological parameters and its residues in soils. Soil was treated with napropamide at 3 mg kg(-1) dry soil and alfalfa plants were cultured for 10 or 30 d, respectively. The maximum value for napropamide accumulation is 0.426 mg kg(-1) in shoots and 2.444 mg kg(-1) in roots. The napropamide-contaminated soil with alfalfa cultivation had much lower napropamide concentrations than the control (soil without alfalfa cultivation). Also, the content of napropamide residue in the rhizosphere was significantly lower than that in the non-rhizosphere soil. M. sativa exposed to 3 mg kg(-1) napropamide showed inhibited growth. Further analysis revealed that plants treated with napropamide accumulated more reactive oxygen species (O(2)(-) and H(2)O(2)) and less amounts of chlorophyll. However, not all cultivars showed oxidative injury, suggesting that the alfalfa cultivars display different tolerance to napropamide. Copyright © 2011 Elsevier B.V. All rights reserved.

Mercury affects the distribution of culturable species of Pseudomonas in soil

DEFF Research Database (Denmark)

Holtze, Maria Sommer; Nielsen, Preben; Ekelund, Flemming

2006-01-01

Pseudomonas bacteria isolated during 52 days on Gould's S1 agar from soil spiked with 0, 3.5 and 15 mg Hg(II) kg soil(-1) were characterised to reveal whether mercury affected them differently. Isolates from the treatments with 0 and 15 mg Hg kg(-1) were characterised using FT-IR characterisation...... was almost exclusively restricted to P. frederiksbergensis and P. migulae groups. We conclude that Hg caused a shift in the dominating species of culturable Pseudomonas....

Physiochemical Influence of Soil Minerals on the Organic Reduction of Soil Chromium

International Nuclear Information System (INIS)

Njoku, P.C.; Nweze, C.A.

2009-01-01

The physiochemical influence of soil minerals (Bentonite, Kaolinite, Diatomite,Rutile and Ferrihydrite) on the organic reduction ofchromium (VI) has been investigated with Oxalic acid as the organic reductant. The effect of pH and particle sizes of the soil minerals were also investigated. Results showed that with 0.1mol/dm3 concentration of Oxalic acid, the concentration of chromium(VI) remaining was 0.28, 0.34,0.38, 0.46 and 0.52mg/kgfor Bentonite, Rutile, Diatomite, Kaolinite and Ferrihydrite respectively whereas at 0.5mol/dm3of oxalic acid, the concentration of chromium reduced to 0.20,0.26, 0.30, 0.38, and0.44mg/kg for Bentonite, Rutile, Diatomite, Kaolinite and Ferrihydrite. Increasedconcentration of oxalic acid increased the reduction of chromium(VI) to chromium(III). At pH 5.0, the concentration of chromium(VI)left was 0.28, 0.34, 0.38,0.46 and 0.52mg/kg forBentonite, Rutile, Diatomite, Kaolinite and Ferrihydrite while at pH 2.5, concentration was0.16, 0.22, 0.26, 0.34 and 0.43mg/kg respectively. At particle size of 47-42 microns, concentration of chromium(VI) was 0.28, 0.34,0.38, 0.46, 0.52mg/kg for the same order ofthe soil minerals. At micron sizes of33-29 and 28-25 ranges the concentration ofchromium(VI) left was 0.23, 0.29, 0.33,0.41 and 0.47mg/kg for both micron sizes and corresponding minerals as well. These results showed that above 33-29 micron sizes, the influence of particle size was negligible. (author)

Heavy Metal Content in Selected Flavouring Plants and in Ultra-Basic Soil of Felda Rokan Barat, Negeri Sembilan, Malaysia

International Nuclear Information System (INIS)

Sahibin Abdul Rahim; Wan Mohd Razi Idris; Zulfahmi Ali Rahman; Tukimat Lihan; Ramlan Omar; Yan, L.K.

2012-01-01

A study was carried out at an ultra basic soil area in Felda Rokan Barat (FRB), Negeri Sembilan. Twenty plants of samples namely chili, turmeric, pandan and lemon grass were collected randomly for the determination of heavy metal contents such as Fe, Cd, Co, Cu, Mn, Ni, Pb, Cr and Zn. Heavy metals in plants were extracted by wet digestion method, whereas available and resistant heavy metals in soil were extracted by sequential extraction. Total heavy metals content in the soil were obtained by summation of resistant and available heavy metals. Heavy metals content in soil and plant extract were determined by using the Flame Atomic Absorption Spectrophotometer (FAAS). Results showed that Fe was the dominant composition in soil in the study area while Cd concentration was very low with values of < 10 mg/ kg. The range of heavy metals concentration in soils were Fe (2618.4 to 4248 mg/ kg), Mn (240.9 to 741.9 mg/ kg), Zn (81.9 to 324.8 mg/ kg), Cr (46.8 to 438.7 mg/ kg), Cu (15.7 to 81.7 mg/ kg), Pb (14.9 to 116.8 mg/ kg), Ni (10.1 to 545.6 mg/ kg), Cd (5.6 to 10.6 mg/ kg) dan Co (0.8 to 126.1 mg/ kg). Available Fe recorded the highest value in all of the plant substrates followed by Mn, Zn, Pb, Ni, Cr, Cu, Co and Cd. Based on percentage of availability Mn, Pb and Zn are considered most available by plant with availability percentage of 8 to 10 %. Concentration of Fe, Mn, Ni and Zn were high in all parts of plants compared to the other metals. The value of biological absorption coefficient (BAC) in chili, turmeric, pandan and lemon grass were in the range of 0.02-0.36, 0.03-0.41, 0.03-0.63 and 0.03-1.15, respectively. It can be concluded that the uptake of heavy metals by plants were normal even though the heavy metals concentration in the ultra basic soil was high. (author)

TRACE ELEMENTS LATERAL DISTRIBUTION AND LIMITATIONS FOR REVEGETATION IN LEAD MINE SOILS: CASE OF LAKHOUAT MINE, TUNISIA

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H. Sahraoui

2016-01-01

Full Text Available Anthropogenic activities such as mining have increased the prevalence and occurrence of trace elements soil contamination. Abandoned mine tailings cause the contamination of adjacent agricultural soils. In Lakhouat mining area (West-Northern Tunisia, the dispersion of particles containing Pb, Zn and Cd results in the contamination of the surrounding agricultural soils. These soils presented high concentrations of Pb (1272 mg kg-1, Zn (5543 mg kg-1 and Cd (25 mg kg-1. Furthermore, the tailing sample and soil sample close the dam tailing presented higher concentrations of Pb, Zn and Cd and conferred more limitation factors for revegetation than adjacent soils of mining area. The main limiting factors of mine soils are their low effective depth, low organic matter content and low phosphorus content and an imbalance between potassium and manganese exchangeable cations. These mine soils are strongly affected by high Pb, Zn and Cd levels which hinder revegetation.

Analysis of Soil Parameters in Almadenejos. Behavior of Mercury in Soil-Plant System

International Nuclear Information System (INIS)

Fernandez, R.; Sierra, M. J.; Villadoniga, M.; Millan, R.

2010-01-01

This scientific-technical report is the result of the stay of Rocio Fernandez Flores practices in the Research Unit soil degradation of the Department of Environment CIEMAT. The aim of this study is to determine the behaviour of mercury in soil of Almadenejos (Almaden, Ciudad Real, Espana) by using a six-step sequential extraction procedure and evaluate the transfer of this pollutant to Marrubium vulgare L., predominant in the area and studied for years due to its ability to accumulate large amounts of mercury without visual symptoms of toxicity. Furthermore, the results will be useful in order to determine if this plant specie could be used as phyto extractor in the recovery mercury contaminated soils. The results show that total mercury concentrations in soil ranged from 709 mg kg-1 to 22,616 mg kg-1. Regarding mercury distribution among different soil fractions, this heavy metal is mainly found in the fraction assigned in the fi nal insoluble residues, the oxidizable fraction and in the crystalline Fe-Mn oxydroxides, on the other hand, barely 1% or lower is readily available to plants However, Marrubium vulgare is able to accumulate high amount of mercury (3.5 - 373.5 mg kg-1). Regarding the mercury distribution inside the plant, mercury concentration in the root was higher than in the aerial part. Within the aerial part the maximum mercury concentration was generally found in leaves. According to the obtained results, Marrubium vulgare L. could be considered as a (hyper)accumulator plant. (Author) 57 refs.

GEMAS - Tin and Tungsten: possible sources of enriched concentrations in soils in European countries

Science.gov (United States)

João Batista, Maria; Filipe, Augusto; Reimann, Clemens

2014-05-01

Tin and tungsten occur related with magmatic differentiation and can be installed in fissures and veins of magmatic rocks or in the neighbor metasediments. Generally, both elements have low chemical mobility in the superficial environment although effectively mobile in detrital media such as stream sediments and deposited in alluvial soils. The most important tin-tungsten deposits in Europe are in Variscides. From the northern Europe, 985 samples and from southern Europe 1123 samples were collected both in agricultural and grazing lands. Analysis were made of Sn , W, pH, TOC, SiO2 from the upper 20 and 10 cm of agricultural and grazing soils, respectively. The present study is part of the GEMAS project a joint project of European geochemical mapping between the EuroGeoSurvey Geochemical Expert Group and EuroMetaux. The results show that in general, at the European (continental) scale natural processes are dominant. It is clear the distinction between NE Europe and SW European tin and tungsten concentrations in soils. Tin geometric mean concentrations in the northern Europe is 0.57 mg kg-1 in agricultural soils and 0.62 mg kg-1 in grazing land; southern Europe 0.91 mg kg-1 in agricultural soils and 0.95 mg kg-1 in grazing land. Tungsten geometric mean concentrations in northern Europe is 0.067 mg kg-1 in agricultural soils and 0.073 mg kg-1 in grazing land and in southern Europe is 0.085 mg kg-1 in agricultural soils and 0.090 mg kg-1 in grazing land. Limit between north and south is the maximum extent of the last glaciation. Grazing land, undisturbed soils for a period of several years, have higher concentrations of Sn and W than agricultural soils which raises the question that if only natural processes are observed. Parent material seems to be the main source of Sn and W to soil. Sn-W rich Variscan granitic intrusions of Central Iberian Zone, Massif Central, Brittany, Cornwall and Bohemia are reflected in soil concentrations. TOC is higher in northern than in

Phytoremediation potential of wild plants growing on soil contaminated with heavy metals.

Science.gov (United States)

Čudić, Vladica; Stojiljković, Dragoslava; Jovović, Aleksandar

2016-09-01

Phytoremediation is an emerging technology that employs higher plants to cleanup contaminated environments, including metal-polluted soils. Because it produces a biomass rich in extracted toxic metals, further treatment of this biomass is necessary. The aim of our study was to assess the five-year potential of the following native wild plants to produce biomass and remove heavy metals from a polluted site: poplar (Populus ssp.), ailanthus (Ailanthus glandulosa L.), false acacia (Robinia pseudoacacia L.), ragweed (Artemisia artemisiifolia L.), and mullein (Verbascum thapsus L). Average soil contamination with Pb, Cd, Zn, Cu, Ni, Cr, and As in the root zone was 22,948.6 mg kg-1, 865.4 mg kg-1, 85,301.7 mg kg-1, 3,193.3 mg kg-1, 50.7 mg kg-1, 41.7 mg kg-1,and 617.9 mg kg-1, respectively. We measured moisture and ash content, concentrations of Pb, Cd, Zn, Cu, Ni, Cr, and As in the above-ground parts of the plants and in ash produced by combustion of the plants, plus gross calorific values. The plants' phytoextraction and phytostabilisation potential was evaluated based on their bioconcentration factor (BCF) and translocation factor (TF). Mullein was identified as a hyperaccumulator for Cd. It also showed a higher gross calorific value (19,735 kJ kg-1) than ragweed (16,469 kJ kg-1).The results of this study suggest that mullein has a great potential for phytoextraction and for biomass generation, and that ragweed could be an effective tool of phytostabilisation.

The effect of pH on the toxicity of zinc oxide nanoparticles to Folsomia candida in amended field soil.

Science.gov (United States)

Waalewijn-Kool, Pauline L; Ortiz, Maria Diez; Lofts, Stephen; van Gestel, Cornelis A M

2013-10-01

The effect of soil pH on the toxicity of 30 nm ZnO to Folsomia candida was assessed in Dorset field soils with pHCaCl2 adjusted to 4.31, 5.71, and 6.39. To unravel the contribution of particle size and dissolved Zn, 200 nm ZnO and ZnCl2 were tested. Zinc sorption increased with increasing pH, and Freundlich kf values ranged from 98.9 (L/kg)(1/n) to 333 (L/kg)(1/n) for 30 nm ZnO and from 64.3 (L/kg)(1/n) to 187 (L/kg)(1/n) for ZnCl2. No effect of particle size was found on sorption, and little difference was found in toxicity between 30 nm and 200 nm ZnO. The effect on reproduction decreased with increasing pH for all Zn forms, with 28-d median effective concentrations (EC50s) of 553 mg Zn/kg, 1481 mg Zn/kg, and 3233 mg Zn/kg for 30 nm ZnO and 331 mg Zn/kg, 732 mg Zn/kg, and 1174 mg Zn/kg for ZnCl2 at pH 4.31, 5.71, and 6.39, respectively. The EC50s based on porewater Zn concentrations increased with increasing pH for 30 nm ZnO from 4.77 mg Zn/L to 18.5 mg Zn/L, while for ZnCl2 no consistent pH-related trend in EC50s was found (21.0-63.3 mg Zn/L). Porewater calcium levels were 10 times higher in ZnCl2 -spiked soils than in ZnO-spiked soils. The authors' results suggest that the decreased toxicity of ZnCl2 compared with 30 nm ZnO based on porewater concentrations was because of a protective effect of calcium and not a particle effect. © 2013 SETAC.

Toxicity of fuel-contaminated soil to Antarctic moss and terrestrial algae.

Science.gov (United States)

Nydahl, Anna C; King, Catherine K; Wasley, Jane; Jolley, Dianne F; Robinson, Sharon A

2015-09-01

Fuel pollution is a significant problem in Antarctica, especially in areas where human activities occur, such as at scientific research stations. Despite this, there is little information on the effects of petroleum hydrocarbons on Antarctic terrestrial biota. The authors demonstrate that the Antarctic mosses Bryum pseudotriquetrum, Schistidium antarctici, and Ceratodon purpureus, and the Antarctic terrestrial alga Prasiola crispa are relatively tolerant to Special Antarctic Blend (SAB) fuel-contaminated soil (measured as total petroleum hydrocarbons). Freshly spiked soils were more toxic to all species than were aged soils containing degraded fuel, as measured by photosynthetic efficiency (variable fluorescence/maximum fluorescence [Fv/Fm]), pigment content, and visual observations. Concentrations that caused 20% inhibition ranged from 16,600 mg/kg to 53,200 mg/kg for freshly spiked soils and from 30,100 mg/kg to 56,200 mg/kg for aged soils. The photosynthetic efficiency of C. purpureus and S. antarctici was significantly inhibited by exposure to freshly spiked soils with lowest-observed-effect concentrations of 27,900 mg/kg and 40,400 mg/kg, respectively. Prasiola crispa was the most sensitive species to freshly spiked soils (Fv/Fm lowest-observed-effect concentration 6700 mg/kg), whereas the Fv/Fm of B. pseudotriquetrum was unaffected by exposure to SAB fuel even at the highest concentration tested (62,900 mg/kg). Standard toxicity test methods developed for nonvascular plants can be used in future risk assessments, and sensitivity data will contribute to the development of remediation targets for petroleum hydrocarbons to guide remediation activities in Antarctica. © 2015 SETAC.

Reduction of Cadmium Uptake of Rice Plants Using Soil Amendments in High Cadmium Contaminated Soil: A Pot Experiment

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Dian Siswanto

2013-05-01

Full Text Available The aims of this study were to investigate the effect of agricultural residues on reducing cadmium uptake in rice plants. The rice plants growing on no cadmium/free cadmium soils (N, Cd soils (Cds, and Cd soils each amended with 1% w/w of coir pith (CP, coir pith modified with sodium hydroxide (CPm and corncob (CC under high cadmium contaminated soil with an average 145 mg Cd kg-1 soil were investigated. The results showed that the cumulative transpiration of rice grown in various treatments under high cadmium contaminated soil followed the order: Cds > CPm ≥ CP ≥ CC. These transpirations directly influenced cadmium accumulation in shoots and husks of rice plants. The CC and CP seemed to work to reduce the cadmium uptake by rice plants indicated by accumulated cadmium in the husk that were 2.47 and 7.38 mg Cd kg-1 dry weight, respectively. Overall, transpiration tended to drive cadmium accumulation in plants for rice grown in high cadmium contaminated soil. The more that plants uptake cadmium, the lower cadmium that remains in the soil.

Response of soil microbial activities and microbial community structure to vanadium stress.

Science.gov (United States)

Xiao, Xi-Yuan; Wang, Ming-Wei; Zhu, Hui-Wen; Guo, Zhao-Hui; Han, Xiao-Qing; Zeng, Peng

2017-08-01

High levels of vanadium (V) have long-term, hazardous impacts on soil ecosystems and biological processes. In the present study, the effects of V on soil enzymatic activities, basal respiration (BR), microbial biomass carbon (MBC), and the microbial community structure were investigated through 12-week greenhouse incubation experiments. The results showed that V content affected soil dehydrogenase activity (DHA), BR, and MBC, while urease activity (UA) was less sensitive to V stress. The average median effective concentration (EC 50 ) thresholds of V were predicted using a log-logistic dose-response model, and they were 362mgV/kg soil for BR and 417mgV/kg soil for DHA. BR and DHA were more sensitive to V addition and could be used as biological indicators for soil V pollution. According to a polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis, the structural diversity of the microbial community decreased for soil V contents ranged between 254 and 1104mg/kg after 1 week of incubation. As the incubation time increased, the diversity of the soil microbial community structure increased for V contents ranged between 354 and 1104mg/kg, indicating that some new V-tolerant bacterial species might have replicated under these conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

Removal of heavy metals from contaminated soil by electrodialytic remediation enhanced with organic acids.

Science.gov (United States)

Merdoud, Ouarda; Cameselle, Claudio; Boulakradeche, Mohamed Oualid; Akretche, Djamal Eddine

2016-11-09

The soil from an industrial area in Algeria was contaminated with Cr (8370 mg kg -1 ), Ni (1135 mg kg -1 ) and zinc (1200 mg kg -1 ). The electrodialytic remediation of this soil was studied using citric acid and EDTA as facilitating agents. 0.1 M citric acid or EDTA was added directly to the soil before it was introduced in an electrodialytic cell in an attempt to enhance the heavy metal solubility in the interstitial fluid. The more acidic pH in the soil when citric acid was used as the facilitating agent was not enough to mobilize and remove the metals from the soil. Only 7.2% of Ni and 6.7% of Zn were removed from the soil in the test with citric acid. The best results were found with EDTA, which was able to solubilize and complex Zn and Ni forming negatively charged complexes that were transported and accumulated in the anolyte. Complete removal was observed for Ni and Zn in the electrodialytic treatment with EDTA. Minor amounts of Cr were removed with both EDTA and citric acid.

Effect of nitrogen and water availability of three soil types on yield, radiation use efficiency and evapotranspiration in field-grown quinoa

DEFF Research Database (Denmark)

Razzaghi, Fatemeh; Plauborg, Finn; Jacobsen, Sven-Erik

2012-01-01

Quinoa (Chenopodium quinoa Willd.) is believed to be tolerant to abiotic stress including salinity, drought and poor soil quality. To investigate the effect of soil type and soil-drying during the seed-filling phase on N-uptake, yield and water use, a Danish-bred cultivar (cv. Titicaca) was grown...... in field lysimeters with sand, sandy loam and sandy clay loam soil. Despite application of the same amount of nitrogen (120 kg N ha−1) to all plots, there were large differences in crop nitrogen-uptake for sandy clay loam (134 kg ha−1), sandy loam (102 kg ha−1) and sand (77 kg ha−1) under full irrigation....... This lead to higher interception of photosynthetic active radiation and higher seed yield on sandy clay loam (3.3 Mg ha−1) and sandy loam (3.0 Mg ha−1) than on sand (2.3 Mg ha−1). The soil with higher clay content had also the highest transpiration, crop evapotranspiration and yield due to the higher uptake...

Spatial Patterns and Risk Assessment of Heavy Metals in Soils in a Resource-Exhausted City, Northeast China

Science.gov (United States)

Chen, Hongwei; An, Jing; Wei, Shuhe; Gu, Jian

2015-01-01

Northeast China is an intensive area of resource-exhausted city, which is facing the challenges of industry conversion and sustainable development. In order to evaluate the soil environmental quality influenced by mining activities over decades, the concentration and spatial distribution of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and Zinc (Zn) in surface soils (0-20cm) of a typical resource-exhausted city were investigated by analyzing 306 soil samples. The results showed that the average concentrations in the samples were 6.17 mg/kg for As, 0.19 mg/kg for Cd, 51.08 mg/kg for Cr, 23.27 mg/kg for Cu, 31.15 mg/kg for Ni, 22.17 mg/kg for Pb, and 54.21 mg/kg for Zn. Metals distribution maps produced by using the inverse distance weighted interpolation method and results revealed that all investigated metals showed distinct geographical patterns, and the concentrations were higher in urban and industrial areas than in farmland. Pearson correlation and principal component analysis showed that there were significant positive correlations (pmetals, and As, Cd, Cr, Mn, Ni, Pb, and Zn were closely associated with the first principal component (PC1), which explained 39.81% of the total variance. Cu and As were mainly associated with the second component (PC2). Based on the calculated Nemerow pollution index, percentage for slightly polluted (1soils were reached 57.33%, while 42.65% topsoil samples are moderate polluted (2soil environmental function areas were classified and proper soil environmental management policy was proposed to decrease the environmental risks in the process of industrial city transformation. PMID:26413806

Vertical distribution of phosphorus in agricultural drainage ditch soils.

Science.gov (United States)

Vaughan, Robert E; Needelman, Brian A; Kleinman, Peter J A; Allen, Arthur L

2007-01-01

Pedological processes such as gleization and organic matter accumulation may affect the vertical distribution of P within agricultural drainage ditch soils. The objective of this study was to assess the vertical distribution of P as a function of horizonation in ditch soils at the University of Maryland Eastern Shore Research Farm in Princess Anne, Maryland. Twenty-one profiles were sampled from 10 agricultural ditches ranging in length from 225 to 550 m. Horizon samples were analyzed for total P; water-extractable P; Mehlich-3 P; acid ammonium oxalate-extractable P, Fe, and Al (P ox, Fe ox, Al ox); pH; and organic C (n = 126). Total P ranged from 27 to 4882 mg kg(-1), P ox from 4 to 4631 mg kg(-1), Mehlich-3 P from 2 to 401 mg kg(-1), and water-extractable P from 0 to 17 mg kg(-1). Soil-forming processes that result in differences between horizons had a strong relationship with various P fractions and P sorption capacity. Fibric organic horizons at the ditch soil surface had the greatest mean P ox, Fe ox, and Al ox concentrations of any horizon class. Gleyed A horizons had a mean Fe ox concentrations 2.6 times lower than dark A horizons and were significantly lower in total P and P ox. Variation in P due to organic matter accumulation and gleization provide critical insight into short- and long-term dynamics of P in ditch soils and should be accounted for when applying ditch management practices.

Effects of six selected antibiotics on plant growth and soil microbial and enzymatic activities

International Nuclear Information System (INIS)

Liu Feng; Ying Guangguo; Tao Ran; Zhao Jianliang; Yang Jifeng; Zhao Lanfeng

2009-01-01

The potential impact of six antibiotics (chlortetracycline, tetracycline and tylosin; sulfamethoxazole, sulfamethazine and trimethoprim) on plant growth and soil quality was studied by using seed germination test on filter paper and plant growth test in soil, soil respiration and phosphatase activity tests. The phytotoxic effects varied between the antibiotics and between plant species (sweet oat, rice and cucumber). Rice was most sensitive to sulfamethoxazole with the EC10 value of 0.1 mg/L. The antibiotics tested inhibited soil phosphatase activity during the 22 days' incubation. Significant effects on soil respiration were found for the two sulfonamides (sulfamethoxazole and sulfamethazine) and trimethoprim, whereas little effects were observed for the two tetracyclines and tylosin. The effective concentrations (EC10 values) for soil respiration in the first 2 days were 7 mg/kg for sulfamethoxazole, 13 mg/kg for sulfamethazine and 20 mg/kg for trimethoprim. Antibiotic residues in manure and soils may affect soil microbial and enzyme activities. - Terrestrial ecotoxicological effects of antibiotics are related to their sorption and degradation behavior in soil.

Effects of six selected antibiotics on plant growth and soil microbial and enzymatic activities

Energy Technology Data Exchange (ETDEWEB)

Liu Feng [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Ying Guangguo, E-mail: guangguo.ying@gmail.co [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Tao Ran; Zhao Jianliang; Yang Jifeng [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Zhao Lanfeng [College of Resource and Environmental Science, South China Agricultural University, Guangzhou 510642 (China)

2009-05-15

The potential impact of six antibiotics (chlortetracycline, tetracycline and tylosin; sulfamethoxazole, sulfamethazine and trimethoprim) on plant growth and soil quality was studied by using seed germination test on filter paper and plant growth test in soil, soil respiration and phosphatase activity tests. The phytotoxic effects varied between the antibiotics and between plant species (sweet oat, rice and cucumber). Rice was most sensitive to sulfamethoxazole with the EC10 value of 0.1 mg/L. The antibiotics tested inhibited soil phosphatase activity during the 22 days' incubation. Significant effects on soil respiration were found for the two sulfonamides (sulfamethoxazole and sulfamethazine) and trimethoprim, whereas little effects were observed for the two tetracyclines and tylosin. The effective concentrations (EC10 values) for soil respiration in the first 2 days were 7 mg/kg for sulfamethoxazole, 13 mg/kg for sulfamethazine and 20 mg/kg for trimethoprim. Antibiotic residues in manure and soils may affect soil microbial and enzyme activities. - Terrestrial ecotoxicological effects of antibiotics are related to their sorption and degradation behavior in soil.

Bioaugmentation of thiabendazole-contaminated soils from a wastewater disposal site: Factors driving the efficacy of this strategy and the diversity of the indigenous soil bacterial community.

Science.gov (United States)

Papadopoulou, Evangelia S; Genitsaris, Savvas; Omirou, Michalis; Perruchon, Chiara; Stamatopoulou, Anastasia; Ioannides, Ioannis; Karpouzas, Dimitrios G

2018-02-01

The application of the fungicide thiabendazole (TBZ) in fruit packaging plants (FPP) results in the production of effluents which are often disposed in adjacent field sites. These require remediation to prevent further environmental dispersal of TBZ. We assessed the bioaugmentation potential of a newly isolated TBZ-degrading bacterial consortium in a naturally contaminated soil (NCS) exhibiting a natural gradient of TBZ levels (12000, 400, 250 and 12 mg kg -1 ). The effect of aging on bioaugmentation efficacy was comparatively tested in a soil with similar physicochemical properties and soil microbiota, which was artificially, contaminated with the same TBZ levels (ACS). The impact of bioaugmentation and TBZ on the bacterial diversity in the NCS was explored via amplicon sequencing. Bioaugmentation effectively removed TBZ from both soils at levels up to 400 mg kg -1 but failed at the highest contamination level (12000 mg kg -1 ). Dissipation of TBZ in bioaugmented samples showed a concentration-dependent pattern, while aging of TBZ had a slight effect on bioaugmentation efficiency. Bioaugmentation had no impact on the soil bacterial diversity, in contrast to TBZ contamination. Soils from the hotspots of TBZ contamination (12000 mg kg -1 ) showed a drastically lower α-diversity driven by the dominance of β- and γ-proteobacteria at the expense of all other bacterial phyla, especially Actinobacteria. Overall, bioaugmentation with specialized microbial inocula could be an effective solution for the recovery of disposal sites contaminated with persistent chemicals like TBZ. Copyright © 2017 Elsevier Ltd. All rights reserved.

Changes in Olsen Phosphorus Concentration and Its Response to Phosphorus Balance in Black Soils under Different Long-Term Fertilization Patterns

Science.gov (United States)

Zhan, Xiaoying; Zhang, Li; Zhou, Baoku; Zhu, Ping; Zhang, Shuxiang; Xu, Minggang

2015-01-01

The Olsen phosphorus (P) concentration of a soil is a key index that can be used to evaluate the P supply capacity of the soil and to estimate the optimal P fertilization rate. A study of the relationship between the soil Olsen P concentration and the P balance (P input minus P output) and their variations among different fertilization patterns will help to provide useful information for proper management of P fertilization. In this paper, the two investigated long-term experiments were established on black soils in the northeast region of China. Six fertilization treatments were selected: (1) unfertilized (CK); (2) nitrogen only (N); (3) nitrogen and potassium (NK); (4) nitrogen and phosphorus (NP); (5) nitrogen, phosphorus, and potassium (NPK); and (6) nitrogen, phosphorus, potassium and manure (NPKM). The results showed that the average Olsen P concentrations in the black soils at Gongzhuling and Harbin (16- and 31-year study periods, respectively), decreased by 0.49 and 0.56 mg kg-1 a-1, respectively, without P addition and increased by 3.17 and 1.78 mg kg-1 a-1, respectively, with P fertilization. The changes in soil Olsen P concentrations were significantly (P<0.05) correlated with the P balances at both sites except for the NP and NPK treatments at Gongzhuling. Under an average deficit of 100 kg ha-1 P, the soil Olsen P concentration at both sites decreased by 1.36~3.35 mg kg-1 in the treatments without P addition and increased by 4.80~16.04 mg kg-1 in the treatments with 100 kg ha-1 of P accumulation. In addition, the changes in Olsen P concentrations in the soil with 100 kg ha-1of P balance were significantly correlated with the P activation coefficient (PAC, percentage of Olsen P to total P, r=0.99, P<0.01) and soil organic matter content (r=0.91, P<0.01). A low pH was related to large changes of Olsen P by 1 kg ha-1 of P balance. These results indicated that soil organic matter and pH have important effects on the change in soil Olsen P by 1 kg ha-1 of P

Effect of some soil amendments on soil properties and plant growth in Southern Thailand acid upland soil

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Onthong, C.

2007-01-01

Full Text Available One of the major factors limiting plant growth is acid soil. In general lime is used for soil amendment in acid soil. However, It has been reported that gypsum or phosphogypsum can be used for ameliorating soilacidity. Pot experiment was conducted to study the effects of lime, phosphogypsum and kieserite on soil properties and plant growth in Kho Hong soil series (coarse loamy, kaolinitic,isohyperthermic, TypicKandiudults which was considered as acid upland soil (pH 5.07. Sweet corn variety INSEE 2 was used as the test crop. The experiment was a completely randomized design with 4 replications and 19 treatments asfollow : unamended, application of hydrated lime and dolomite to raise soil pH at 5.5, application of hydrated lime and dolomite combined with phosphogypsum at the rate that can supply calcium 0.25, 0.50,0.75 and 1 time of both limes, application of hydrated lime and dolomite combined with kieserite at the rate 0.25, 0.50,0.75 and 1 times of sulfur requirement for corn (40 kg S ha-1. The result showed that shoot and root dry weights of corn were increased when lime materials, phosphogypsum and kieserite were applied and the drymatter weights were increased according to the increasing of phosphogypsum and kieserite. The maximum shoot dry weight (18.98 g pot-1 was obtained when 1 times of kieserite was supplied with dolomite and wassignificantly (P<0.01 higher than those of the unamended treatment, only hydrated lime and dolomite treatments, which had dry weights of 12.64, 15.18 and 15.67 g pot-1 respectively. Phosphorus and K uptakewere not significantly different in all treatments and the lowest uptake of N, Ca, Mg and S was obtained in the unamended treatment. The maximum uptake of N (512.10 mg pot-1 was found when 0.5 times ofphosphogypsum was applied together with dolomite. Calcium and Mg uptake was likely to increase according to the increasing rate of soil amendment application. Highest uptake of Ca (42.51 mg pot-1 was obtainedwhen

Single Low Dose Primaquine (0.25 mg/kg Does Not Cause Clinically Significant Haemolysis in G6PD Deficient Subjects.

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Germana Bancone

.7% were greater than in G6PD normal subjects (0.3%, -0.8 and -1.7% but were clinically insignificant. Fractional drops in haemoglobin concentration larger than 25% following single dose primaquine were observed in 1.8% of the population but were asymptomatic.The single low dose (0.25mg/kg of primaquine is clinically well tolerated and can be used safely without prior G6PD testing in populations with high prevalence of G6PD deficiency. The present evidence supports a broader use of low dose primaquine without G6PD testing for the treatment and elimination of falciparum malaria.ClinicalTrials.gov NCT01872702.

Effects of aluminium water treatment residuals, used as a soil amendment to control phosphorus mobility in agricultural soils.

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Ulén, Barbro; Etana, Ararso; Lindström, Bodil

2012-01-01

Phosphorus (P) leaching from agricultural soils is a serious environmental concern. Application of aluminium water treatment residuals (Al-WTRs) at a rate of 20 Mg ha(-1) to clay soils from central Sweden significantly increased mean topsoil P sorption index (PSI) from 4.6 to 5.5 μmol kg(-1) soil. Mean degree of P saturation in ammonium lactate extract (DPS-AL) significantly decreased from 17 to 13%, as did plant-available P (P-AL). Concentrations of dissolved reactive P (DRP) decreased by 10-85% in leaching water with Al-WTR treatments after exposure of topsoil lysimeters to simulated rain. Soil aggregate stability (AgS) for 15 test soils rarely improved. Three soils (clay loam, silty loam and loam sand) were tested in greenhouse pot experiments. Aluminium-WTR application of 15 or 30 ton ha(-1) to loam sand and a clay loam with P-AL values of 80-100 mg kg(-1) soil significantly increased growth of Italian ryegrass when fertilised with P but did not significantly affect growth of spring barley on any soil. Al-WTR should only be applied to soils with high P fertility where improved crop production is not required.

[Soil Olsen-P content changing trend and its relationship with phosphorus surplus and crop yield under long-term fertilization in loessial soil region on the Loess Plateau, China].

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E, Sheng Zhe; Yang, Zhi Qi; Zeng, Xi Bai; Wang, Ya Nan; Luo, Zhao Xia; Yuan, Jin Hua; Che, Zong Xian

2017-11-01

The changing trend of soil available phosphorus (Olsen-P) content in soil and its relationship with soil phosphorus surplus and crop yield are fundamental when making appropriate phosphate fertilizer recommendations. In this paper, the influences of long-term fertilization on crops phosphorus uptake, soil phosphorus surplus, changing trend of soil available phosphorus content and relationships of soil available phosphorus content with soil phosphorus surplus and crop yield were investigated through 34 years (1981-2015) long-term trial in loessial soil region on the Loess Plateau. The experiment had a completely-randomized-block split-plot design in triplicate. Two main-plot treatments were no farmyard manure and farmyard manure (M), and four subplot treatments were CK (no fertilizer), N (application of chemical fertilizer N), NP (application of chemical fertilizer NP) and NPK (balanced application of chemical fertilizer NPK), respectively. The results showed that fertilization treatments and crop types significantly influenced uptake amount of phosphorus and soil phosphorus surplus. Averaged over time from 1981 to 2015, wheat mean phosphorus uptake amounts of CK, N, NP, NPK, M, MN, MNP and MNPK were 8.63, 10.64, 16.22, 16.21, 16.25, 17.83, 20.39 and 20.27 kg·hm -2 , while rape phosphorus uptakeamounts of eight treatments were 4.40, 8.38, 15.08, 15.71, 10.52, 11.23, 17.96 and 17.66 kg·hm -2 , respectively. The surplus amount of soil phosphorus significantly correlated with the amount of phosphorus applied to soil. When soil phosphorus surplus amount equal zero, wheat and rape phosphorus input amounts were 10.47 kg·hm -2 and 6.97 kg·hm -2 , respectively. Soil phosphorus surplus amount significantly influenced the changing trend of available phosphorus content in soil. CK and N treatments had no phosphorus input, and soil available phosphorus content exhibited a declining trend, annually decreased by 0.16 mg·kg -1 and 0.15 mg·kg -1 , respectively. In contrast

Residue studies of Methabenzthiazuron in Soil, Lentils and Hay

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Al-Maghrabi, K.I.

2002-01-01

Over two years, replicate plots of lentils (Lens culinaris L.) were treated before seeding with methabenzthiazuron at a rate of 0.5 kg a.i. ha-1. In each year representative soil, lentil and hay samples were randomly collected from plots of each treatment. Soil samples were tested for residues 24 hours after treatment and harvest. Lentil and hay samples were tested at harvest. A cleanup step was conducted after extraction. Gas chromatograph equipped with a nitrogen/phosphorus detector was used to detect methabenzthiazuron. Overall average of residue levels in soil decreased significantly from 1.16+-0.15 mg kg, 24 hours after treatment, 0.12 +-0.01 mg kg at harvest. No significant difference in the maximum average residue was found in lentil and hay samples collected from various plots and tested at harvest (0.10+-0.01 and 0.19 +-0.02 mg kg in lentils and hay, respectively). Recovery tests were conducted with each group of samples tested in order to determine the efficiency of analytical procedure. (author)

Cadmium and cadmium-tolerant soil bacteria in cacao crops from northeastern Colombia.

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Bravo, D; Pardo-Díaz, S; Benavides-Erazo, J; Rengifo-Estrada, G; Braissant, O; Leon-Moreno, C

2018-05-01

This research aims to assess total-cadmium soil content and microbiological aspects to understand the dynamics of culturable cadmium-tolerant bacteria (CdtB) in cacao soils from northeastern Colombia. An integration of inverted dish plating, Cd determination and a microcalorimetry assay (IMC) was carried out. A farm in Boyacá showed the highest level of total soil Cd (3·74 mg kg -1 ) followed by farms in Santander and Arauca (2·76 and 1·16 mg kg -1 , respectively). Coefficient of determination between total soil Cd and CFU of CdtB was high (R 2  = 0·83) for the farm in Boyacá. Moreover, a pool of 129 CdtB was isolated, and phylogeny of 21 CdtB was discussed. Among CdtB strains isolated, Enterobacter sp. CdDB41 showed major Cd immobilization capacity (Q max of 2·21 and 2·32 J at 6 and 24 mg l -1 of CdCl 2 ), with an immobilization rate of 0·220 mg kg -1  h -1 . Among CdtB strains isolated, Enterobacter sp. CdDB41 showed major Cd immobilization capacity (Q max of 2·21 and 2·32 J at 6 and 24 mg l -1 of CdCl 2 ), with an immobilization rate of 0·220 mg kg -1  h -1 . Nothing is known about soil CdtB in cacao. Our data showed that CdtB such as Enterobacter sp. has high immobilization capacity. Furthermore, the otavite found in situ might be mineralized due to the bacterial metabolic activity of CdtB. © 2018 The Society for Applied Microbiology.

Metal pollution (Cd, Pb, Zn, and As) in agricultural soils and soybean, Glycine max, in southern China.

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Zhao, Yunyun; Fang, Xiaolong; Mu, Yinghui; Cheng, Yanbo; Ma, Qibin; Nian, Hai; Yang, Cunyi

2014-04-01

Crops produced on metal-polluted agricultural soils may lead to chronic toxicity to humans via the food chain. To assess metal pollution in agricultural soils and soybean in southern China, 30 soybean grain samples and 17 soybean-field soil samples were collected from 17 sites in southern China, and metal concentrations of samples were analyzed by graphite furnace atomic absorption spectrophotometer. The integrated pollution index was used to evaluate if the samples were contaminated by Cd, Pb, Zn and As. Results showed that Cd concentration of 12 samples, Pb concentration of 2 samples, Zn concentration of 2 samples, and As concentrations of 2 samples were above the maximum permissible levels in soils. The integrated pollution index indicated that 11 of 17 soil samples were polluted by metals. Metal concentrations in soybean grain samples ranged from 0.11 to 0.91 mg kg(-1) for Cd; 0.34 to 2.83 mg kg(-1) for Pb; 42 to 88 mg kg(-1) for Zn; and 0.26 to 5.07 mg kg(-1) for As, which means all 30 soybean grain samples were polluted by Pb, Pb/Cd, Cd/Pb/As or Pb/As. Taken together, our study provides evidence that metal pollution is an important concern in agricultural soils and soybeans in southern China.

Effect of biochar produced at different pyrolysis temperature on the soil respiration of abandoned mine soil

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Kim, Yong Seong; Kim, Juhee; Hwang, Wonjae; Hyun, Seunghun

2015-04-01

infrared gas sensor, and these data were sent to a data logger. During the measuring periods, the cumulative CO2 emission were similar between the control (516.8 mg-CO2 kg-1-soil) and BC4 5% mixture (519.3 mg-CO2 kg-1-soil), while BC7 5% mixture was significantly decreased (356.1 mg-CO2 kg-1-soil) compared to other treatment and control. Because the degradation rate of biochar generally increased with decreasing pyrolysis temperature, this result suggest that the soil respiration rates of biochar amended soils are affected by physico-chemical properties of biochar during early incubation periods (about 1 weeks), For example, surface properties of used biochars, which are related to adsorption of soil organic matter and CO2, have different properties with pyrolysis temperature such as specific surface area (BC4=5.08 m2g-1; BC7=260.75 m2 g-1, respectively), average pore diameter (BC4=4,673 nm; BC7=2,606 nm, respectively), and functional groups of biochar surface. However, there was not clear evidence of biochar-mine soil interaction process, because of the short observation periods. Future work should focus on the adsorption of CO2 and soil organic matter of biochar and soil-biochar interaction with long time periods and various biological test.

Using electrocoagulation for metal and chelant separation from washing solution after EDTA leaching of Pb, Zn and Cd contaminated soil.

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Pociecha, Maja; Lestan, Domen

2010-02-15

Electrocoagulation with an Al sacrificial anode was tested for the separation of chelant and heavy metals from a washing solution obtained after leaching Pb (3200 mg kg(-1)), Zn (1100 mg kg(-1)), and Cd (21 mg kg(-1)) contaminated soil with EDTA. In the electrochemical process, the sacrificial anode corroded to release Al(3+) which served as coagulant for precipitation of chelant and metals. A constant current density of 16-128 mAc m(-2) applied between the Al anode and the stainless-steel cathode removed up to 95% Pb, 68% Zn and 66% Cd from the soil washing solution. Approximately half of the initial EDTA remained in the washing solution after treatment, up to 16.3% of the EDTA was adsorbed on Al coagulant and precipitated, the rest of the EDTA was degraded by anodic oxidation. In a separate laboratory-scale remediation experiment, we leached a soil with 40 mmol EDTA per kg of soil and reused the washing solution (after electrocoagulation) in a closed loop. It removed 53% of Pb, 26% of Zn and 52% of Cd from the soil. The discharge solution was clear and colourless, with pH 7.52 and 170 mg L(-1) Pb, 50 mg L(-1) Zn, 1.5 mg L(-1) Cd and 11 mM EDTA.

Physicochemical characteristics of the rhizosphere soils of some cereal crops in Ambo Woreda, West Shoa, Ethiopia

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Louis E. Attah

2010-03-01

Full Text Available In this study, physicochemical properties of rhizosphere soils of some cereal crops in Ambo Woreda, West Shoa in Ethiopia have been investigated. Soil samples were collected from four different localities, viz. Awaro, Senkele, Meja and Guder, and their edaphic characteristics are determined. The soils are dominated by clay (40.4-45.8% along with coarse particles of sand. Bulk density, organic carbon (1.52-1.81% and electrical conductivity (1.3-1.9 dSm are low in all the soil samples. The soils are acidic with pH varying from 6.2 to 6.7. There are similarities in the relatively low content of available phosphorus (1.4-2.4 mg kg-1 and high available nitrogen content (480-986 mg kg-1 in all the soil samples while available potassium content (240-496 mg kg-1 is found to be medium in Awaro soil but high in the other three soil samples. Deficiencies are observed in the levels of available micro-nutrients (Cu: 1.2-1.8 µg g-1, Zn: 1.2-1.8 µg g-1 and Mn: 3.2-3.8 µg g-1 while the Fe content is sufficient in all the soil samples (340-496 µg g-1. With proper soil management, the farmlands studied are recommended for the cultivation of cereal crops.

Results of field studies on 90SR and stable SR soil-to-plant transfer

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Gerzabek, M.H.; Artner, C.; Horak, O.; Mueck, K.

1992-01-01

In 1987 and 1988 at 35 sites plants ready to harvest and the corresponding soils (0 - 20 cm) were collected for 90 Sr and stable strontium analyses. Sample preparation and measurement led to a detection limit of 0.008 Bq 90 Sr kg -1 . The 90 Sr-contamination of Austrian soils ranged from 396 to 1998 Bq m -2 . Known from literature the contribution of the Chernobyl fallout amounted to app. 25 % of the total contamination. Stable strontium contents of the soils were between 6 and 62.5 mg kg -1 . Bariumtriethanolamine extracted 17.7 to 62.3 % of the total stable Sr in soil. 90 Sr-concentrations in cereal grains ranged from 0.03 to 0.67 Bq kg -1 (fresh wight) for maize and barley, respectively. The values for other foodstuff were between 0.15 (white cabbage) and 0.91 Bq kg -1 (spinach). Stable strontium contents were between 0.079 mg kg -1 (maize) and 72.5 mg kg -1 (celery shoot). The following mean 90 Sr soil-to-plant transfer factors for cereal grains were obtained: 0.010 (maize), 0.097 (rye), 0.049 (wheat), 0.095 (barley). Transfer factors for straw were up to 50 times higher (maize). The transfer of 90 Sr into vegetables and potatoes reached the same order of magnitude compared to the cereals. In all cases soil-to-plant transfer of stable Sr was clearly lower up to 60 % of the respective values for 90 Sr. Thus natural stable strontium is less plant available than 90 Sr. The influence of soil parameters on the 90 Sr transfer into plants was examinated by correlation analyses. Increasing exchangeable calcium contents of the soils resulted in a significant reduction of Sr soil-to-barley straw transfer. (authors)

Energetic contaminants inhibit plant litter decomposition in soil.

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Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Sunahara, Geoffrey I; Hawari, Jalal

2018-05-30

Individual effects of nitrogen-based energetic materials (EMs) 2,4-dinitrotoluene (2,4-DNT), 2-amino-4,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), nitroglycerin (NG), and 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (CL-20) on litter decomposition, an essential biologically-mediated soil process, were assessed using Orchard grass (Dactylis glomerata) straw in Sassafras sandy loam (SSL) soil, which has physicochemical characteristics that support "very high" qualitative relative bioavailability for organic chemicals. Batches of SSL soil were separately amended with individual EMs or acetone carrier control. To quantify the decomposition rates, one straw cluster was harvested from a set of randomly selected replicate containers from within each treatment, after 1, 2, 3, 4, 6, and 8 months of exposure. Results showed that soil amended with 2,4-DNT or NG inhibited litter decomposition rates based on the median effective concentration (EC50) values of 1122 mg/kg and 860 mg/kg, respectively. Exposure to 2-ADNT, 4-ADNT or CL-20 amended soil did not significantly affect litter decomposition in SSL soil at ≥ 10,000 mg/kg. These ecotoxicological data will be helpful in identifying concentrations of EMs in soil that present an acceptable ecological risk for biologically-mediated soil processes. Published by Elsevier Inc.

Decontamination of metals, pentachlorophenol, and polychlorined dibenzo-p-dioxins and dibenzofurans polluted soil in alkaline conditions using an amphoteric biosurfactant.

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Reynier, Nicolas; Blais, Jean-François; Mercier, Guy; Besner, Simon

2014-01-01

In this paper, flotation in acidic conditions and alkaline leaching soil washing processes were compared to decontaminate four soils with variable contamination with metals, pentachlorophenol (PCP), and polychlorodibenzo dioxins and furans (PCDD/F). The measured concentrations of the four soils prior treatment were between 50 and 250 mg/kg for As, 35 and 220mg/kg for Cr, 80 and 350mg/kg for Cu, and 2.5 and 30mg/kg for PCP. PCDD/F concentrations reached 1394, 1375, 3730, and 6289ng/kg for F1, S1, S2, and S3 soils, respectively. The tests were carried out with masses of 100g of soil (fraction 0-2 mm) in a 2 L beaker or in a 1 L flotation cell. Soil flotation in sulphuric acid for 1 h at 60 degreeC with three flotation cycles using the surfactant cocamidopropyl betaine (BW) at 1% allows the solubilization of metals and PCP with average removal yields of 85%, 51%, 90%, and 62% for As, Cr, Cu, and PCP, respectively. The alkaline leaching for 2 h at 80 degreeC solubilizes As, Cr, Cu, and PCP with average removal yields of 60%, 32%, 77%, and 87%, respectively. Tests on PCDD/F solubilization with different surfactants were carried out in combination with the alkaline leaching process. PCDD/F removal yields of 25%, 72%, 70%, and 74% for F1, S1, S2, and S3 soils, respectively, were obtained using the optimized conditions.

Growth and Cadmium Phytoextraction by Swiss Chard, Maize, Rice, Noccaea caerulescens, and Alyssum murale in Ph Adjusted Biosolids Amended Soils.

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Broadhurst, C Leigh; Chaney, Rufus L; Davis, Allen P; Cox, Albert; Kumar, Kuldip; Reeves, Roger D; Green, Carrie E

2015-01-01

Past applications of biosolids to soils at some locations added higher Cd levels than presently permitted. Cadmium phytoextraction would alleviate current land use constraints. Unamended farm soil, and biosolids amended farm and mine soils were obtained from a Fulton Co., IL biosolids management facility. Soils contained 0.16, 22.8, 45.3 mg Cd kg(-1) and 43.1, 482, 812 mg Zn kg(-1) respectively with initial pH 6.0, 6.1, 6.4. In greenhouse studies, Swiss chard (Beta vulgaris var. cicla), a Cd-accumulator maize (inbred B37 Zea mays) and a southern France Cd-hyperaccumulator genotype of Noccaea caerulescens were tested for Cd accumulation and phytoextraction. Soil pH was adjusted from ∼5.5-7.0. Additionally 100 rice (Oryza sativa) genotypes and the Ni-hyperaccumulator Alyssum murale were screened for potential phytoextraction use. Chard suffered phytotoxicity at low pH and accumulated up to 90 mg Cd kg(-1) on the biosolids amended mine soil. The maize inbred accumulated up to 45 mg Cd kg(-1) with only mild phytotoxicity symptoms during early growth at pH>6.0. N. caerulescens did not exhibit phytotoxicity symptoms at any pH, and accumulated up to 235 mg Cd kg(-1) in 3 months. Reharvested N. caerulescens accumulated up to 900 mg Cd kg(-1) after 10 months. Neither Alyssum nor 90% of rice genotypes survived acceptably. Both N. caerulescens and B37 maize show promise for Cd phytoextraction in IL and require field evaluation; both plants could be utilized for nearly continuous Cd removal. Other maize inbreds may offer higher Cd phytoextraction at lower pH, and mono-cross hybrids higher shoot biomass yields. Further, maize grown only for biomass Cd maximum removal could be double-cropped.

Distribution and risk evaluation of heavy metals in agricultural soils of southeastern Zunyi city, China

International Nuclear Information System (INIS)

Chen Hongliang; Xu Huajie; Song Yuping; Tan Hong; Xie Feng; He Jinlin

2008-01-01

The pollution of heavy metals (As, Pb, Cd, Cr, and Hg) in agricultural soils of Southeastern Zunyi, Guizhou Province were investigated and assessed in this paper. The results showed that the average contents of heavy metals in the soils were As 11.39mg/kg, Pb 38.75mg/kg, Cd 0.34mg/kg, Cr 40.45mg/kg, Hg 0.21mg/kg. The Cd is the main contamination element, with an average single pollution index of 1.13, and an average single ecological risk index of 50.85, showing this area is in medium ecological risk class. The highest pollution index is 1.43 in Zunyi County, with an average single ecological risk index of 64.35. The results also indicated that Cd and Hg had caused some relevant ecological risk by comparing the pollution index with the ecological risk index of heavy metals. (authors)

Remediation of cadmium contaminated water and soil using vinegar residue biochar.

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Li, Yuxin; Pei, Guangpeng; Qiao, Xianliang; Zhu, Yuen; Li, Hua

2018-06-01

This study investigated a new biochar produced from vinegar residue that could be used to remediate cadmium (Cd)-contaminated water and soil. Aqueous solution adsorption and soil incubation experiments were performed to investigate whether a biochar prepared at 700 °C from vinegar residue could efficiently adsorb and/or stabilize Cd in water and soil. In the aqueous solution adsorption experiment, the Cd adsorption process was best fitted by the pseudo-second-order kinetic and Freundlich isotherm models. If the optimum parameters were used, i.e., pH 5 or higher, a biochar dosage of 12 g L -1 , a 10 mg L -1 Cd initial concentration, and 15-min equilibrium time, at 25 °C, then Cd removal could reach about 100%. The soil incubation experiment evaluated the biochar effects at four different application rates (1, 2, 5, and 10% w/w) and three Cd contamination rates (0.5, 1, and 2.5 mg kg -1 ) on soil properties and Cd fractionation. Soil pH and organic matter increased after adding biochar, especially at the 10% application rate. At Cd pollution levels of 1.0 or 2.5 mg kg -1 , a 10% biochar application rate was most effective. At 0.5 mg Cd kg -1 soil, a 5% biochar application rate was most efficient at transforming the acid extractable and easily reducible Cd fractions to oxidizable and residual Cd. The results from this study demonstrated that biochar made from vinegar residue could be a new and promising alternative biomass-derived material for Cd remediation in water and soil.

Geochemical background of zinc, cadmium and mercury in anthropically influenced soils in a semi-arid zone (SE, Spain)

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García-Lorenzo, M. L.; Pérez-Sirvent, C.; Martínez-Sánchez, M. J.; Molina, J.; Tudela, M. L.; Hernández-Córdoba, M.

2009-04-01

This work seeks to establish the geochemical background for three potentially toxic trace elements (Zn, Cd and Hg) in a pilot zone included in the DesertNet project in the province of Murcia. The studied area, known as Campo de Cartagena, Murcia (SE Spain) is an area of intensive agriculture and has been much affected over the years by anthropic activity. The zone can be considered an experimental pilot zone for establishing background levels in agricultural soils. Sixty four samples were collected and corresponded to areas subjected to high and similar agricultural activity or soils with natural vegetation, which correspond to abandoned agricultural areas. The Zn content was determined by flame atomic absorption spectrometry. The Cd content was determined by electrothermal atomization atomic absorption spectrometry and mercury content was determined by atomic fluorescence spectrometry. Geostatistical analysis consisting of kriging and mapping was performed using the geostatistical analyst extension of ArcGIS 8.3. Zinc values ranged from 10 mg kg-1 to 151 mg kg-1, with an average value of 45 mg kg-1. Cadmium values ranged between 0.1 mg kg-1 and 0.9mg kg-1, with a mean value of 0.3 mg kg-1 and mercury values ranged from 0.1 mg kg-1 to 2.3 mg kg-1, with a mean value of 0.5 mg kg-1. At a national level, the Spanish Royal Decree 9/2005 proposes toxicological and statistical approaches to establish background values. According to the statistical approach, background values consist of the median value for the selected element. The background values for Zn, Cd and Hg in the studied area were 40 mg kg-1 for Zn, 0.3 mg kg-1 for Cd and 0.4 mg kg-1 for Hg.

Decontamination of Heavy Metals in Polluted Soil by Phytoremediation Using Bryophyllum Pinnatum

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Ekwumemgbo P. A.

2013-04-01

Full Text Available Phytoremediation is the use of specially selected or engineered living green plants for in situ risk reduction and/or removal of pollutants from contaminated media. This process is one of the most rapidly developing components of environmentally friendly (green and cost-effective technology to abate environmental pollution. The risk reduction could be through the process of removal, degradation, containment of a contaminant or a combination of any of these factors. Bryophyllum pinnatum a herbally-accepted plant in some parts of the world was cultivated in ten different plastic buckets containing heavy metal polluted soil and nurtured for 20 months. The plants were left in ambient conditions and watered periodically. After the first 2 weeks, the plant and soil samples were collected and analysed for total concentration of Cd, Cr, Cu, Ni, Pb V and Zn. Subsequently, the plant and soil samples were collected monthly and analysed for the total concentrations of these heavy metals, using Atomic Absorption Spectrophotometry. Maximum extracted heavy metals from soil by plant were Cd (3.12±1.03 mg/kg, Cr (32.48±3.21 mg/kg, Cu (81.01±2.3 mg/kg Ni (11.91±2.32 mg/kg, Pb (399.90 ±4.32 mg/kg V (5.81±0.08 mg/kg and Zn (150.51± 0.33 and this occurred in the 4th month of study. This study confirms B. pinnatum as one of the plants that could be employed in phytoremediation of soil polluted by heavy metals.

Spatial Patterns and Risk Assessment of Heavy Metals in Soils in a Resource-Exhausted City, Northeast China.

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Hongwei Chen

Full Text Available Northeast China is an intensive area of resource-exhausted city, which is facing the challenges of industry conversion and sustainable development. In order to evaluate the soil environmental quality influenced by mining activities over decades, the concentration and spatial distribution of arsenic (As, cadmium (Cd, chromium (Cr, copper (Cu, nickel (Ni, lead (Pb, and Zinc (Zn in surface soils (0-20cm of a typical resource-exhausted city were investigated by analyzing 306 soil samples. The results showed that the average concentrations in the samples were 6.17 mg/kg for As, 0.19 mg/kg for Cd, 51.08 mg/kg for Cr, 23.27 mg/kg for Cu, 31.15 mg/kg for Ni, 22.17 mg/kg for Pb, and 54.21 mg/kg for Zn. Metals distribution maps produced by using the inverse distance weighted interpolation method and results revealed that all investigated metals showed distinct geographical patterns, and the concentrations were higher in urban and industrial areas than in farmland. Pearson correlation and principal component analysis showed that there were significant positive correlations (p<0.05 between all of the metals, and As, Cd, Cr, Mn, Ni, Pb, and Zn were closely associated with the first principal component (PC1, which explained 39.81% of the total variance. Cu and As were mainly associated with the second component (PC2. Based on the calculated Nemerow pollution index, percentage for slightly polluted (1

soils were reached 57.33%, while 42.65% topsoil samples are moderate polluted (2soil environmental function areas were classified and proper soil environmental management policy was proposed to decrease the environmental risks in the process of industrial city transformation.

Spatial distribution and vertical variation of arsenic in Guangdong soil profiles, China

International Nuclear Information System (INIS)

Zhang, H.H.; Yuan, H.X.; Hu, Y.G.; Wu, Z.F.; Zhu, L.A.; Zhu, L.; Li, F.B.; LI, D.Q.

2006-01-01

Total of 260 soil profiles were reported to investigate the arsenic spatial distribution and vertical variation in Guangdong province. The arsenic concentration followed an approximately lognormal distribution. The arsenic geometric mean concentration of 10.4 mg/kg is higher than that of China. An upper baseline concentration of 23.4 mg/kg was estimated for surface soils. The influence of soil properties on arsenic concentration was not important. Arsenic spatial distributions presented similar patterns that high arsenic concentration mainly located in limestone, and sandshale areas, indicating that soil arsenic distribution was dependent on bedrock properties than anthropogenic inputs. Moreover, from A- to C-horizon arsenic geometric mean concentrations had an increasing tendency of 10.4, 10.7 to 11.3 mg/kg. This vertical variation may be related to the lower soil organic matter and soil degradation and erosion. Consequently, the soil arsenic export into surface and groundwaters would reach 1040 t year -1 in the study area. - Soil arsenic movement export is a potential threat to the water quality of the study area

Mercury baseline levels in Flemish soils (Belgium)

International Nuclear Information System (INIS)

Tack, Filip M.G.; Vanhaesebroeck, Thomas; Verloo, Marc G.; Van Rompaey, Kurt; Ranst, Eric van

2005-01-01

It is important to establish contaminant levels that are normally present in soils to provide baseline data for pollution studies. Mercury is a toxic element of concern. This study was aimed at assessing baseline mercury levels in soils in Flanders. In a previous study, mercury contents in soils in Oost-Vlaanderen were found to be significantly above levels reported elsewhere. For the current study, observations were extended over two more provinces, West-Vlaanderen and Antwerpen. Ranges of soil Hg contents were distinctly higher in the province Oost-Vlaanderen (interquartile range from 0.09 to 0.43 mg/kg) than in the other provinces (interquartile ranges from 0.7 to 0.13 and 0.7 to 0.15 mg/kg for West-Vlaanderen and Antwerpen, respectively). The standard threshold method was applied to separate soils containing baseline levels of Hg from the data. Baseline concentrations for Hg were characterised by a median of 0.10 mg Hg/kg dry soil, an interquartile range from 0.07 to 0.14 mg/kg and a 90% percentile value of 0.30 mg/kg. The influence of soil properties such as clay and organic carbon contents, and pH on baseline Hg concentrations was not important. Maps of the spatial distribution of Hg levels showed that the province Oost-Vlaanderen exhibited zones with systematically higher Hg soil contents. This may be related to the former presence of many small-scale industries employing mercury in that region. - Increased mercury levels may reflect human activity

ARSENIC AND COPPER UPTAKE BY CABBAGES GROWN ON POLLUTED SOILS

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Nguyen Thi Kim Phuong

2017-11-01

Full Text Available Cabbages (Brassica Juncea (L. Czern were grown in pot experiments on typical unpolluted and polluted soils with concentration changing from 20.50 - 50.00 mg As/kg and 156.00 - 413.00 mg Cu/kg dry soil. The results demonstrate the elevation of As and Cu in soil may lead to increased uptake by these cabbages subsequent entry into human food chain. It was found 11.84- 32.12 mg As/kg and 46.86 - 94.47 mg Cu/kg dry leaves. It has tendency increase uptake and accumulation of Cu in cabbage tissue with increasing cultivated time, whereas, it was found accumulation of As in cabbages tissue decreased with time prolonging. The quantity of As and Cu in these cabbages, were significant higher than 0.2 mg As/kg and 5.0 mg Cu/kg fresh vegetable, the permissible limit concentration in fresh vegetable. This indicated that human may As and Cu exposure occur through eating these vegetables.

Optimization of ultrasonic extraction and analyses methodology by HPLC for determination of diuron and its metabolites in soil cultivation of sugar cane

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Maria Josefa Santos Yabe

2009-03-01

Full Text Available Diuron, N-(3,4-dichlorophenyl-N, N-dimethylurea can be transformed into the soil through the biodegradation of 3-(3,4-dichlorophenyl-3-methylurea (DCPMU, 3.4-diclorofenilureia (DCPU and 3,4-dichloroaniline (DCA. This study aimed to optimize and validate a method of extraction and analysis of these substances in the soil by HPLC/DAD. There was extracted with methanol in the bath ultrasonic and analysis in a liquid chromatograph/detector brand Waters. The condition of analysis optimized for separation of analytes was mobile phase methanol: water 50:50 (v / v, flow 1 mL min-1. Wavelength of 240 nm was selected for the DCA and 254 nm for diuron, DCPMU and DCPU. It was used column and pre column Waters Xterra RP18, 5 um, 4.6 and 3.9 x 150 mm x 20 mm. The calibration curve was obtained from the fortification of the soil with the mixture of patterns in the range of 5 mg Kg-1 to 200 mg Kg-1 of soil. The recovery was obtained in two concentration levels of 5 and 200 mg. Kg-1 of soil was between 85 and 99%. The repeatability was 0.78%, 2.20%, 2.17% and 1.72% and intermediate precision was 2.48%, 2.11%, 3.10% and 2.77% for diuron, DCPMU, DCPU and DCA, respectively. The limit of quantification was 1.25 mg Kg-1 soil. The concentration of diuron found in some bioaugmented soil samples ranged from 5.5 to 8.9 mg Kg-1 soil, but was not detected the presence of their metabolites.

Electrokinetic remediation of fluorine-contaminated soil and its impact on soil fertility.

Science.gov (United States)

Zhou, Ming; Wang, Hui; Zhu, Shufa; Liu, Yana; Xu, Jingming

2015-11-01

Compared to soil pollution by heavy metals and organic pollutants, soil pollution by fluorides is usually ignored in China. Actually, fluorine-contaminated soil has an unfavorable influence on human, animals, plants, and surrounding environment. This study reports on electrokinetic remediation of fluorine-contaminated soil and the effects of this remediation technology on soil fertility. Experimental results showed that electrokinetic remediation using NaOH as the anolyte was a considerable choice to eliminate fluorine in contaminated soils. Under the experimental conditions, the removal efficiency of fluorine by the electrokinetic remediation method was 70.35%. However, the electrokinetic remediation had a significant impact on the distribution and concentrations of soil native compounds. After the electrokinetic experiment, in the treated soil, the average value of available nitrogen was raised from 69.53 to 74.23 mg/kg, the average value of available phosphorus and potassium were reduced from 20.05 to 10.39 mg/kg and from 61.31 to 51.58 mg/kg, respectively. Meanwhile, the contents of soil available nitrogen and phosphorus in the anode regions were higher than those in the cathode regions, but the distribution of soil available potassium was just the opposite. In soil organic matter, there was no significant change. These experiment results suggested that some steps should be taken to offset the impacts, after electrokinetic treatment.

Metais pesados, agrotóxicos e combustíveis: efeito na população de colêmbolos no solo Heavy metal, pesticides and fuels: effect in the population of collembola in the soil

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Zaida Inês Antoniolli

2013-06-01

Full Text Available O objetivo deste trabalho foi avaliar o desenvolvimento de colêmbolos no solo com diferentes níveis de metais pesados, combustíveis e agrotóxicos em condição de laboratório. Os tratamentos foram: Cádmio (1, 10 e 100mg kg-1 de solo; Cobre (50, 500 e 5000mg kg-1 de solo; Zinco (100, 1000 e 10000mg kg-1 de solo; fungicida epoxiconazol + piraclostrobina (1 e 2L ha-1; fungicida epoxiconazol (0,75 e 1,5L ha-1; herbicida glifosato (2 e 4L ha-1; óleo lubrificante queimado (5, 50 e 100mL kg-1 solo e óleo diesel (5, 50 e 100mL kg-1 solo e controle. Na dose de 1mg kg-1 de Cd no solo, houve grande aumento na população de colêmbolos e o pH do solo diminuiu à medida que aumentaram as doses de Cd, Zn e Cu no solo. Na presença de combustíveis, os colêmbolos apresentaram incapacidade de reprodução, independente da dose aplicada no solo. O número de colêmbolos apresentou incremento com o aumento da dosagem de glifosato e epoxiconazol. Os metais pesados Cu e Zn têm ação negativa sobre a população de colêmbolos e somente o Cd (1mg kg-1 solo proporciona aumento na população de colêmbolos no solo. A presença de óleo lubrificante queimado e óleo diesel no solo inibem o desenvolvimento dos colêmbolos no solo. Os agrotóxicos glifosato, epoxiconazol e epoxiconazol + piraclostrobina não influenciam negativamente sobre a população de colêmbolos no solo.The aim of this research was to evaluate the collembola development in soils with different levels of heavy metals, fuels and pesticides, in laboratory conditions. Treatments were: Cadmium - 1, 10 and 100mg kg-1 soil; Copper - 50, 500 and 5000mg kg-1 soil; Zinc - 100, 1000 and 10000 mg kg-1 soil; fungicide epoxiconazol + piraclostrobina - 1 and 2L ha-1; fungicide epoxiconazol - 0,75 and 1,5L ha-1; herbicide glyphosate - 2 and 4L ha-1; burned lubricating oil - 5, 50 and 100mL kg-1 soil and diesel oil - 5, 50 and 100mL kg-1 soil and control. In the 1mg kg-1 dose of Cd there was a great

Cleaning the Soil from Zinc Using Red Clovers “Arimaičiai”

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Audronė Mikalajūnė

2011-02-01

Full Text Available Zinc as a nutrition element is required to plants in small quantities to maintain normal functions of metabolism mechanisms. Our work analyses the efficiency of red clovers “Arimaičiai” for cleaning zinc from the soil contaminated with zinc under laboratory conditions. Seeds were sown in three differently polluted soils: clean soil, once contaminated with zinc and periodically contaminated with zinc soil. Zinc concentration in one time contaminated soil was 45 mg/kg. After 6 months of phytoremediation, the remained zinc concentration in the soil was 3 times lower comparing with the initial concentration. It was also determined that under such conditions, the uptake of red clovers made approximately 65% of zinc. Permanent soil contamination with zinc increased concentration before phytoremediation up to 80 mg/kg. After 6 months of phytoremediation, zinc concentration was determined to be 1.9 times lower. Otherwise, the soil was permanently contaminated with larger zinc quantities and after application of which reached 300 mg/kg. In this case, following half a year of phytoremediation, zinc concentration in the soil was 1.7 times lower comparing with the initial concentration after contamination. It was determined that the uptake of red clovers made approximately 17% of zinc.Article in Lithuanian

Soil fertility status and nutrients provided to spring barley (Hordeum distichon L. by pig slurry

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Melisa Gómez-Garrido

2014-03-01

Full Text Available Nutrient recycling using pig slurry is a common agricultural practice to manage the ever-increasing amounts of wastes from the pig industry. This study was conducted in the southeast of Spain to quantify the enrichments in major (N, P, K, Mg and minor (Zn, Fe, Cu, and Mn nutrients in soils amended with D1-170 kg N ha-1 (European Union legislated dose or D2-340 kg N ha-1, and understand the influence of pig slurry on yield and nutrient uptake in two crop seasons of spring barley (Hordeum distichon L. Compared to control, D2 increased NO3--N by 11.4X to 109 mg kg-1, Olsen-P by 6.9X to 423 mg kg-1, exchange K (2.5X to 1.6 cmol+ kg-1, Mg (1.7X to 1.8 cmol+ kg-1, diethylene-triamine pentaacetic acid (DTPA-Zn (94X to 18.2 mg kg-1, and Fe (2X to 11.3 mg kg-1. Available NO3--N, Olsen-P, and DTPA-Zn have the best correlations with crop yield and nutrient uptake. These results indicate that the assessment of soil fertility status at 1-mo after pig slurry addition provides a good indicator for potential yield and uptake of barley. However, it is suggested that leachates should be monitored to effectively manage potential releases of nitrate and phosphate into the environment.

Comparative toxicity of imidacloprid and thiacloprid to different species of soil invertebrates.

Science.gov (United States)

de Lima E Silva, Cláudia; Brennan, Nicola; Brouwer, Jitske M; Commandeur, Daniël; Verweij, Rudo A; van Gestel, Cornelis A M

2017-05-01

Neonicotinoid insecticides have come under increasing scrutiny for their impact on non-target organisms, especially pollinators. The current scientific literature is mainly focused on the impact of these insecticides on pollinators and some aquatic insects, leaving a knowledge gap concerning soil invertebrates. This study aimed at filling this gap, by determining the toxicity of imidacloprid and thiacloprid to five species of soil invertebrates: earthworms (Eisenia andrei), enchytraeids (Enchytraeus crypticus), Collembola (Folsomia candida), oribatid mites (Oppia nitens) and isopods (Porcellio scaber). Tests focused on survival and reproduction or growth, after 3-5 weeks exposure in natural LUFA 2.2 standard soil. Imidacloprid was more toxic than thiacloprid for all species tested. F. candida and E. andrei were the most sensitive species, with LC 50 s of 0.20-0.62 and 0.77 mg/kg dry soil for imidacloprid and 2.7-3.9 and 7.1 mg/kg dry soil for thiacloprid. EC 50 s for effects on the reproduction of F. candida and E. andrei were 0.097-0.30 and 0.39 mg/kg dry soil for imidacloprid and 1.7-2.4 and 0.44 mg/kg dry soil for thiacloprid. The least sensitive species were O. nitens and P. scaber. Enchytraeids were a factor of 5-40 less sensitive than the taxonomically related earthworm, depending on the endpoint considered. Although not all the species showed high sensitivity to the neonicotinoids tested, these results raise awareness about the effects these insecticides can have on non-target soil invertebrates.

Feasibility Process for Remediation of the Crude Oil Contaminated Soil

Science.gov (United States)

Keum, H.; Choi, H.; Heo, H.; Lee, S.; Kang, G.

2015-12-01

More than 600 oil wells were destroyed in Kuwait by Iraqi in 1991. During the war, over 300 oil lakes with depth of up to 2m at more than 500 different locations which has been over 49km2. Therefore, approximately 22 million m3was crude oil contaminated. As exposure of more than 20 years under atmospheric conditions of Kuwait, the crude oil has volatile hydrocarbons and covered heavy oily sludge under the crude oil lake. One of crude oil contaminated soil which located Burgan Oilfield area was collected by Kuwait Oil Company and got by H-plus Company. This contaminated soil has about 42% crude oil and could not biodegraded itself due to the extremely high toxicity. This contaminated soil was separated by 2mm sieve for removal oil sludge ball. Total petroleum hydrocarbons (TPH) was analysis by GC FID and initial TPH concentration was average 48,783 mg/kg. Ten grams of the contaminated soil replaced in two micro reactors with 20mL of bio surfactant produce microorganism. Reactor 1 was added 0.1g powder hemoglobin and other reactor was not added hemoglobin at time 0 day. Those reactors shake 120 rpm on the shaker for 7 days and CO2 produced about 150mg/L per day. After 7 days under the slurry systems, the rest days operated by hemoglobin as primary carbon source for enhanced biodegradation. The crude oil contaminated soil was degraded from 48,783mg/kg to 20,234mg/kg by slurry process and final TPH concentration degraded 11,324mg/kg for 21days. Therefore, highly contaminated soil by crude oil will be combined bio slurry process and biodegradation process with hemoglobin as bio catalytic source. Keywords: crude-oil contaminated soil, bio slurry, biodegradation, hemoglobin ACKOWLEDGEMENTS This project was supported by the Korea Ministry of Environment (MOE) GAIA Program

Ecological risk assessment and carcinogen health risk assessment of arsenic in soils from part area of the Daye City, China

Science.gov (United States)

Li, F.; Wang, T.; Xiao, M. S.; Cai, Y.; Zhuang, Z. Y.

2018-01-01

Soils in four sampling sites from part area of the Daye City were collected. Concentrations of arsenic (As) in soils in sampling sites were detected by Atomic Fluorescence Spectrometry, ecological risk was calculated by potential ecological risk index (RI) and human health risk was measured by human health risk assessment model established by USEPA. The results showed that, the total content of As in soils in Daye was decreased in the order of S4 (66.58 mg/kg)>S2 (44.73 mg/kg)>S3 (34.86 mg/kg) >S1 (21.84 mg/kg), concentrations in all sampling sites were higher than background values of Hubei Province. The potential risk and human health risk were decreased in the order of S4>S2>S3>S1 and S4>S3>S2>S1, respectively. Specially, S1, S2 and S3 were at low potential ecological risk while S4 was at moderate ecological risk. But there was no carcinogenic risk for human exposure to As in soil in Daye.

[Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province and evaluation of its ecological risk].

Science.gov (United States)

Jin, Shu-Lan; Huang, Yi-Zong; Wang, Fei; Xu, Feng; Wang, Xiao-Ling; Gao, Zhu; Hu, Ying; Qiao Min; Li, Jin; Xiang, Meng

2015-03-01

Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province was studied. The results showed that copper mining and smelting could increase the content of rare earth elements in soils and crops. Rare earth elements content in farmland soils of the surrounding Yinshan Lead Zinc Copper Mine and Guixi Smelting Plant varied from 112.42 to 397.02 mg x kg(-1) and 48.81 to 250.06 mg x kg(-1), and the average content was 254.84 mg x kg(-1) and 144.21 mg x kg(-1), respectively. The average contents of rare earth elements in soils in these two areas were 1.21 times and 0.68 times of the background value in Jiangxi province, 1.36 times and 0.77 times of the domestic background value, 3.59 times and 2.03 times of the control samples, respectively. Rare earth elements content in 10 crops of the surrounding Guixi Smelting Plant varied from 0.35 to 2.87 mg x kg(-1). The contents of rare earth elements in the leaves of crops were higher than those in stem and root. The contents of rare earth elements in Tomato, lettuce leaves and radish leaves were respectively 2.87 mg x kg(-1), 1.58 mg x kg(-1) and 0.80 mg x kg(-1), which were well above the hygienic standard limit of rare earth elements in vegetables and fruits (0.70 mg x kg(-1)). According to the health risk assessment method recommended by America Environmental Protection Bureau (USEPA), we found that the residents' lifelong average daily intake of rare earth elements was 17.72 mg x (kg x d)(-1), lower than the critical value of rare earth elements damage to human health. The results suggested that people must pay attention to the impact of rare earth elements on the surrounding environment when they mine and smelt copper ore in Jiangxi.

Key indicator tools for shallow slope failure assessment using soil chemical property signatures and soil colour variables.

Science.gov (United States)

Othman, Rashidi; Hasni, Shah Irani; Baharuddin, Zainul Mukrim; Hashim, Khairusy Syakirin Has-Yun; Mahamod, Lukman Hakim

2017-10-01

Slope failure has become a major concern in Malaysia due to the rapid development and urbanisation in the country. It poses severe threats to any highway construction industry, residential areas, natural resources and tourism activities. The extent of damages that resulted from this catastrophe can be lessened if a long-term early warning system to predict landslide prone areas is implemented. Thus, this study aims to characterise the relationship between Oxisols properties and soil colour variables to be manipulated as key indicators to forecast shallow slope failure. The concentration of each soil property in slope soil was evaluated from two different localities that consist of 120 soil samples from stable and unstable slopes located along the North-South Highway (PLUS) and East-West Highway (LPT). Analysis of variance established highly significant difference (P shallow slope failure were high value of L*(62), low values of c* (20) and h* (66), low concentration of iron (53 mg kg -1 ) and aluminium oxide (37 mg kg -1 ), low soil TOC (0.5%), low CEC (3.6 cmol/kg), slightly acidic soil pH (4.9), high amount of sand fraction (68%) and low amount of clay fraction (20%).

Assessment of Cu applications in two contrasting soils-effects on soil microbial activity and the fungal community structure.

Science.gov (United States)

Keiblinger, Katharina M; Schneider, Martin; Gorfer, Markus; Paumann, Melanie; Deltedesco, Evi; Berger, Harald; Jöchlinger, Lisa; Mentler, Axel; Zechmeister-Boltenstern, Sophie; Soja, Gerhard; Zehetner, Franz

2018-03-01

Copper (Cu)-based fungicides have been used in viticulture to prevent downy mildew since the end of the 19th century, and are still used today to reduce fungal diseases. Consequently, Cu has built up in many vineyard soils, and it is still unclear how this affects soil functioning. The present study aimed to assess the short and medium-term effects of Cu contamination on the soil fungal community. Two contrasting agricultural soils, an acidic sandy loam and an alkaline silt loam, were used for an eco-toxicological greenhouse pot experiment. The soils were spiked with a Cu-based fungicide in seven concentrations (0-5000 mg Cu kg -1 soil) and alfalfa was grown in the pots for 3 months. Sampling was conducted at the beginning and at the end of the study period to test Cu toxicity effects on total microbial biomass, basal respiration and enzyme activities. Fungal abundance was analysed by ergosterol at both samplings, and for the second sampling, fungal community structure was evaluated via ITS amplicon sequences. Soil microbial biomass C as well as microbial respiration rate decreased with increasing Cu concentrations, with EC 50 ranging from 76 to 187 mg EDTA-extractable Cu kg -1 soil. Oxidative enzymes showed a trend of increasing activity at the first sampling, but a decline in peroxidase activity was observed for the second sampling. We found remarkable Cu-induced changes in fungal community abundance (EC 50 ranging from 9.2 to 94 mg EDTA-extractable Cu kg -1 soil) and composition, but not in diversity. A large number of diverse fungi were able to thrive under elevated Cu concentrations, though within the order of Hypocreales several species declined. A remarkable Cu-induced change in the community composition was found, which depended on the soil properties and, hence, on Cu availability.

Enzyme activity as an indicator of soil-rehabilitation processes at a zinc and lead ore mining and processing area.

Science.gov (United States)

Ciarkowska, Krystyna; Sołek-Podwika, Katarzyna; Wieczorek, Jerzy

2014-01-01

The activities of soil enzymes in relation to the changes occurring in the soil on a degraded area in southern Poland after zinc and lead mining were analyzed. An evaluation of the usefulness of urease and invertase activities for estimating the progress of the rehabilitation processes in degraded soil was performed. The data show that the soil samples differed significantly in organic carbon (0.68-104.0 g kg(-1)) and total nitrogen (0.03-8.64 g kg(-1)) content in their surface horizons. All of the soil samples (apart from one covered with forest) had very high total concentrations of zinc (4050-10,884 mg kg(-1)), lead (959-6661 mg kg(-1)) and cadmium (24.4-174.3 mg kg(-1)) in their surface horizons, and similar concentrations in their deeper horizons. Nevertheless, the amounts of the soluble forms of the above-mentioned heavy metals were quite low and they accounted for only a small percentage of the total concentrations: 1.4% for Zn, 0.01% for Pb and 2.6% for Cd. Urease activities were ranked as follows: soil from flotation settler (0.88-1.78 μg N-NH4(+) 2h(-1) g(-1))slag heaps (1.77-2.51 μg N-NH4(+) 2h(-1) g(-1))slag heaps, ranging from 20.5 to 77.1mg of the inverted sugar, but they were much lower in soil from the flotation settler (0.12-6.95 mg of the inverted sugar). The results demonstrated that heavy pollution with Zn, Pb and Cd slightly decreased the activities of urease and invertase. It is thought that it resulted from the enzyme reactions occurring in slightly acidic or alkaline soil conditions. Under such conditions, heavy metals occur mainly in insoluble forms. The activities of these enzymes are strongly dependent on the content and decomposition of organic matter in the soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

Persistence of endosulfan and its metabolites in tomato plants and soil

International Nuclear Information System (INIS)

Carazo, E.; Barquero, M.; Valverde, B.

1999-01-01

Tests were conducted to study the persistence of 14 C-labelled α and β -endosulfan in tomato plants and soil under the greenhouse conditions when applied at the rate and number of applications used by tomato growers in Costa Rica. Two applications, at 30 and 55 days after planting were made. Plant and soil samples were extracted 37, 49, 71 and 125 days after planting and analyzed by LSC, TLC and GC-ECD. At 37 days after planting the compounds identified were α-endosulfan, β-endosulfan and endosulfan sulphate with a combined concentration of 3.6 mg/kg in plant and 0.6 mg/kg in the soil. At 49 days after planting the same three compounds were found at the combined concentration of 1.51 mg/kg in the plant and at 0.34 mg/kg in the soil. After 71 days low levels of α-endosulfan, β-endosulfan, endosulfan sulphate and endosulfan lactone were found in plants and soil. Similarly, at 125 days low levels of these compounds as well as low levels of two other metabolites, endosulfan alcohol and endosulfan ether were detected. Under the conditions of the experiment endosulfan residues do not seem to be significant or persistant. (author)

Lead contamination in soil and vegetation of areas surrounding ...

African Journals Online (AJOL)

The results show significant negative correlation between waste pH and Pb in industrial waste, plant and soil. Also the results show that Acantholimon sp. and Astragalus glancanthus were dominant plant in two mines upon floristic quantities assay. Lead concentration was 15.8 mg/kg DW and 1.61 mg/kg DW in Ghanat ...

Distribution of some artificial and natural radionuclides and trace elements in Syrian soils

International Nuclear Information System (INIS)

Al-Masri, M. S.; Shaik Khalil, H.; Amin, Y.; Ibrahim, S.; Hassan, M.

2004-07-01

Within the environmental monitoring program in Syria, about 115 surface soil and 38 profile soil samples were collected and analyzed during the period of 1998 to 2003 in order to determine the levels of natural and artificial radionuclides and some of trace elements (Cu, Zn, Cd, Pb). The concentrations of the natural radionuclides in the surface samples were found to vary from area to another and ranged from 2-50 Bq/kg, 4-228 Bq/kg, 4-55 Bq/kg, 1-143 Bq/kg and 96-672 Bq/kg for 224 Ra, 226 Ra, 228 Ra, 137 Cs and 04 K, respectively. While, the concentrations of the studied trace elements were varied between 0.5-5.6 mg/kg for U, 3.2-31.7 mg/kg for Pb, 14-141 mg/kg for Zn, 1.6-114 mg/kg for Cu and 0.25-2.7 mg/kg for Cd. Most of the reported values in this study were in the range of the natural uncontaminated surface soil concentrations and published values in many countries in the world. The results showed that the relation between the distribution of the natural radionuclides and depth was approximately the same for all radionuclides except for 137 Cs, which was extremely binded in the upper layers of soil. In addition, some differences in the concentrations of the studied trace elements with depth were observed. These differences may be due to the average of rainfall and the existence of some potential sources of contamination of such elements. However, the results of this study can be considered as a database for the natural background in Syria that helps to establish the radiation map of the country.(author)

Arsenic in the soils of Zimapan, Mexico

Energy Technology Data Exchange (ETDEWEB)

Ongley, Lois K. [Oak Hill High School, P.O. Box 400, Sabattus, ME 04280 (United States)]. E-mail: loisongley@earthlink.net; Sherman, Leslie [Department of Chemistry, Washington College, 300 Washington Avenue, Chestertown, MD 21620 (United States); Armienta, Aurora [Instituto de Geofisica, UNAM, Mexico D.F. 04510 (Mexico); Concilio, Amy [Department of Earth, Ecological, and Environmental Sciences, University of Toledo, Toledo, OH 43606 (United States); Salinas, Carrie Ferguson [Department of Agronomy and Environmental Management, Louisiana State University, Baton Rouge, LA 70803 (United States)

2007-02-15

Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapan Valley range from 4 to 14 700 mg As kg{sup -1}. Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg{sup -1} only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment. -- Much of the arsenic is relatively immobile but presents long-term source of arsenic.

Arsenic in the soils of Zimapan, Mexico

International Nuclear Information System (INIS)

Ongley, Lois K.; Sherman, Leslie; Armienta, Aurora; Concilio, Amy; Salinas, Carrie Ferguson

2007-01-01

Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapan Valley range from 4 to 14 700 mg As kg -1 . Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg -1 only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment. -- Much of the arsenic is relatively immobile but presents long-term source of arsenic

Biological Activity Assessment in Mexican Tropical Soils with Different Hydrocarbon Contamination Histories.

Science.gov (United States)

Riveroll-Larios, Jessica; Escalante-Espinosa, Erika; Fócil-Monterrubio, Reyna L; Díaz-Ramírez, Ildefonso J

The use of soil health indicators linked to microbial activities, such as key enzymes and respirometric profiles, helps assess the natural attenuation potential of soils contaminated with hydrocarbons. In this study, the intrinsic physicochemical characteristics, biological activity and biodegradation potential were recorded for two soils with different contamination histories (>5 years and soil samples. Soil suspensions were tested as microbial inocula in biodegradation potential assays using contaminated perlite as an inert support. The basal respiratory rate of the recently contaminated soil was 15-38 mg C-CO 2  kg -1 h -1 , while the weathered soil presented a greater basal mineralisation capacity of 55-70 mg C-CO 2 kg -1 h -1 . The basal levels of lipase and dehydrogenase were significantly greater than those recorded in non-contaminated soils (551 ± 21 μg pNP g -1 ). Regarding the biodegradation potential assessment, the lipase (1000-3000 μg pNP g -1 of perlite) and dehydrogenase (~3000 μg INF g -1 of perlite) activities in the inoculum of the recently contaminated soil were greater than those recorded in the inoculum of the weathered soil. This was correlated with a high mineralisation rate (~30 mg C-CO 2 kg -1 h -1 ) in the recently contaminated soil and a reduction in hydrocarbon concentration (~30 %). The combination of an inert support and enzymatic and respirometric analyses made it possible to detect the different biodegradation capacities of the studied inocula and the natural attenuation potential of a recently contaminated soil at high hydrocarbon concentrations.

Phytoextraction by arsenic hyperaccumulator Pteris vittata L. from six arsenic-contaminated soils: Repeated harvests and arsenic redistribution

Energy Technology Data Exchange (ETDEWEB)

Gonzaga, Maria I.S.; Santos, Jorge A.G. [Department of Soil Chemistry, Universidade Federal da Bahia, Cruz das Almas, 44380000 (Brazil); Ma, Lena Q. [Soil and Water Science Department, University of Florida, 2169 McCarty Hall, Gainesville, FL 32611-0290 (United States)], E-mail: lqma@ifas.ufl.edu

2008-07-15

This greenhouse experiment evaluated arsenic removal by Pteris vittata and its effects on arsenic redistribution in soils. P. vittata grew in six arsenic-contaminated soils and its fronds were harvested and analyzed for arsenic in October, 2003, April, 2004, and October, 2004. The soil arsenic was separated into five fractions via sequential extraction. The ferns grew well and took up arsenic from all soils. Fern biomass ranged from 24.8 to 33.5 g plant{sup -1} after 4 months of growth but was reduced in the subsequent harvests. The frond arsenic concentrations ranged from 66 to 6,151 mg kg{sup -1}, 110 to 3,056 mg kg{sup -1}, and 162 to 2,139 mg kg{sup -1} from the first, second and third harvest, respectively. P. vittata reduced soil arsenic by 6.4-13% after three harvests. Arsenic in the soils was primarily associated with amorphous hydrous oxides (40-59%), which contributed the most to arsenic taken up by P. vittata (45-72%). It is possible to use P. vittata to remediate arsenic-contaminated soils by repeatedly harvesting its fronds. - Pteris vittata was effective in continuously removing arsenic from contaminated soils after three repeated harvests.

Soil type and texture impacts on soil organic carbon accumulation in a sub-tropical agro-ecosystem

Energy Technology Data Exchange (ETDEWEB)

Gonçalves, Daniel Ruiz Potma; Sa, Joao Carlos de Moraes; Mishra, Umakant; Cerri, Carlos Eduardo Pellegrino; Ferreira, Lucimara Aparecida; Furlan, Flavia Juliana Ferreira

2016-11-02

Soil organic carbon (C) plays a fundamental role in tropical and subtropical soil fertility, agronomic productivity, and soil health. As a tool for understand ecosystems dynamics, mathematical models such as Century have been used to assess soil's capacity to store C in different environments. However, as Century was initially developed for temperate ecosystems, several authors have hypothesized that C storage may be underestimated by Century in Oxisols. We tested the hypothesis that Century model can be parameterized for tropical soils and used to reliably estimate soil organic carbon (SOC) storage. The aim of this study was to investigate SOC storage under two soil types and three textural classes and quantify the sources and magnitude of uncertainty using the Century model. The simulation for SOC storage was efficient and the mean residue was 10 Mg C ha^-1 (13%) for n = 91. However, a different simulation bias was observed for soil with <600 g kg^-1 of clay was 16.3 Mg C ha^-1 (18%) for n = 30, and at >600 g kg^-1 of clay, was 4 Mg C ha^-1 (5%) for n = 50, respectively. The results suggest a non-linear effect of clay and silt contents on C storage in Oxisols. All types of soil contain nearly 70% of Fe and Al oxides in the clay fraction and a regression analysis showed an increase in model bias with increase in oxides content. Consequently, inclusion of mineralogical control of SOC stabilization by Fe and Al (hydro) oxides may improve results of Century model simulations in soils with high oxides contents

Residues and Analysis of Degradation of Novel Fungicide Picoxystrobin in Cucumber and Soil Under Field Conditions

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SUN Yang

2014-10-01

Full Text Available The analytical method for the residues of picoxystrobin in cucumber vegetable and soil matrices was developed and the dissipation of picoxystrobin under field conditions was studied. The limit of detection(LODof picoxystrobin was 3.5×10 -11 g and the limit of quantifica-tion(LOQwas found to be 0.005 mg·kg -1 in cucumber and soil. At three different spiking levels(0.005, 0.05, 0.25 mg·kg -1, mean recoveries and relative standard deviation(RSDfrom fortified samples in five replicated experiments for each matrix were in the range of 68.61%-122.4% and 1.06%-17.2%, respectively. The results showed that the half-lives of picoxystrobin in cucumber and soil from Tianjin City were 5.71 d and 12.9 d, respectively, the half-lives of picoxystrobin in cucumber and soil from Shandong Province were 2.70 d and 10.3 d, respec-tively, and the half-lives of picoxystrobin in cucumber and soil from Jiangsu Province were 9.76 d and 14.9 d, respectively. The maximum residual concentration of picoxystrobin on the 5th day after the last application was 0.014 mg· kg -1, much lower than the Maximum Residue Limits(MRLsfor picoxystrobin in cucumber according to the standards of EU(0.05 mg·kg-1.

Assessment of natural sepiolite on cadmium stabilization, microbial communities, and enzyme activities in acidic soil.

Science.gov (United States)

Sun, Yuebing; Sun, Guohong; Xu, Yingming; Wang, Lin; Liang, Xuefeng; Lin, Dasong; Hu, Fazhi

2013-05-01

A pot trial was conducted to assess the efficiency of sepiolite-induced cadmium (Cd) immobilization in ultisoils. Under Cd concentrations of 1.25, 2.5, and 5 mg kg(-1), the available Cd in the soil after the application of 1-10 % sepiolite decreased by a maximum of 44.4, 23.0, and 17.0 %, respectively, compared with no sepiolite treatments. The increase in the values of soil enzyme activities and microbial number proved that a certain metabolic recovery occurred after sepiolite treatment. The dry biomass of spinach (Spinacia oleracea) increased with increasing sepiolite concentration in the soil. However, the concentration (dry weight) of Cd in the spinach shoots decreased with the increase in sepiolite dose, with maximum reduction of 92.2, 90.0, and 84.9 %, respectively, compared with that of unamended soils. Under a Cd level of 1.25 mg kg(-1), the Cd concentration in the edible parts of spinach at 1 % sepiolite amendment was lower than 0.2 mg kg(-1) fresh weight, the maximum permissible concentration (MPC) of Cd in vegetable. Even at higher Cd concentrations (2.5 and 5 mg kg(-1)), safe spinach was produced when the sepiolite treatment was up to 5 %. The results showed that sepiolite-assisted remediation could potentially succeed on a field scale by decreasing Cd entry into the food chain.

Heavy metal bioaccumulation in selected medicinal plants collected from Khetri copper mines and comparison with those collected from fertile soil in Haridwar, India.

Science.gov (United States)

Maharia, R S; Dutta, R K; Acharya, R; Reddy, A V R

2010-02-01

Heavy metal distribution in medicinal plants is gaining importance not only as an alternative medicine, but also for possible concern due to effects of metal toxicity. The present study has been focused on emphasizing the heavy metal status and bioaccumulation factors of V, Mn, Fe, Co, Cu, Zn, Se (essential metals) and Cr, Ni, Cd, As and Pb (potentially toxic metals) in medicinal plants grown under two different environmental conditions e.g., near to Khetri copper mine and those in fertile soils of Haridwar, both in India, using Instrumental Neutron Activation Analysis (relative method) and Atomic Absorption Spectrometry. The copper levels in the medicinal plants from Khetri were found to be 3-4 folds higher (31.6-76.5 mg kg(-1)) than those from Haridwar samples (7.40-15.3 mg kg(-1)), which is correlated with very high copper levels (763 mg kg(-1)) in Khetri soil. Among various heavy metals, Cr (2.60-5.92 mg kg(-1)), Cd (1.47-2.97 mg kg(-1)) and Pb (3.97-6.63 mg kg(-1)) are also higher in concentration in the medicinal plants from Khetri. The essential metals like Mn (36.4-69.3 mg kg(-1)), Fe (192-601 mg kg(-1)), Zn (24.9-49.9 mg kg(-1)) and Se (0.13-0.91 mg kg(-1)) and potentially toxic metals like Ni (3.09-9.01 mg kg(-1)) and As (0.41-2.09 mg kg(-1)) did not show much variations in concentration in the medicinal plants from both Khetri and Haridwar. The medicinal plants from Khetri, e.g., Ocimum sanctum, Cassia fistula, Withania somnifera and Azadirachta Indica were found rich in Ca and Mg contents while Aloe barbadensis showed moderately high Ca and Mg. Higher levels of Ca-Mg were found to correlate with Zn (except Azadirachta Indica). The bioaccumulation factors (BAFS) of the heavy metals were estimated to understand the soil-to-plant transfer pattern of the heavy metals. Significantly lower BAF values of Cu and Cr were found in the medicinal plants from Khetri, indicating majority fraction of these metals are precipitated and were immobilized species

Carbazole degradation in the soil microcosm by tropical bacterial strains

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Lateef B. Salam

2015-01-01

Full Text Available In a previous study, three bacterial strains isolated from tropical hydrocarbon-contaminated soils and phylogenetically identified as Achromobacter sp. strain SL1, Pseudomonassp. strain SL4 and Microbacterium esteraromaticum strain SL6 displayed angular dioxygenation and mineralization of carbazole in batch cultures. In this study, the ability of these isolates to survive and enhance carbazole degradation in soil were tested in field-moist microcosms. Strain SL4 had the highest survival rate (1.8 x 107 cfu/g after 30 days of incubation in sterilized soil, while there was a decrease in population density in native (unsterilized soil when compared with the initial population. Gas chromatographic analysis after 30 days of incubation showed that in sterilized soil amended with carbazole (100 mg/kg, 66.96, 82.15 and 68.54% were degraded by strains SL1, SL4 and SL6, respectively, with rates of degradation of 0.093, 0.114 and 0.095 mg kg−1 h−1. The combination of the three isolates as inoculum in sterilized soil degraded 87.13% carbazole at a rate of 0.121 mg kg−1 h−1. In native soil amended with carbazole (100 mg/kg, 91.64, 87.29 and 89.13% were degraded by strains SL1, SL4 and SL6 after 30 days of incubation, with rates of degradation of 0.127, 0.121 and 0.124 mg kg−1h−1, respectively. This study successfully established the survivability (> 106 cfu/g detected after 30 days and carbazole-degrading ability of these bacterial strains in soil, and highlights the potential of these isolates as seed for the bioremediation of carbazole-impacted environments.

Biological treatment: Soil impacted with crude oil

International Nuclear Information System (INIS)

Gilbertson, N.; Severns, J.J.

1992-01-01

Biological land treatment proved to be a successful way to manage contamination at a California oil and gas production property. During the project, approximately 120,000 yards of contaminated soil was treated in the treatment plots to below the cleanup goals of 1,000 milligrams per kilograms (mg/kg) total petroleum hydrocarbons. In general, remaining hydrocarbon levels in treated soil were the 200 mg/kg total petroleum hydrocarbons range or lower. Cleanup goals were achieved in less than 2 months for each lift of soil treated. The treated soil was used as fill material in the excavation. No significant odor problems occurred during the project. Groundwater monitoring confirmed that no impact to groundwater occurred due to the biological land treatment process. Design of the treatment plan and regulatory requirements are also discussed

Toxicity of four veterinary pharmaceuticals on the survival and reproduction of Folsomia candida in tropical soils.

Science.gov (United States)

Zortéa, Talyta; Segat, Julia C; Maccari, Ana Paula; Sousa, José Paulo; Da Silva, Aleksandro S; Baretta, Dilmar

2017-04-01

This study aimed to evaluate the effect of veterinary pharmaceuticals (VPs) used to control endo- and ectoparasites in ruminants, on the survival and reproduction of the collembolan species Folsomia candida. Standard ecotoxicological tests were conducted in Tropical Artificial Soil and the treatments consisted of increasing dosages of four commercial products with different active ingredients: ivermectin, fipronil, fluazuron and closantel. Ecotoxicological effects were related to the class and mode of action of the different compounds. Fipronil and ivermectin were the most toxic compounds causing a significant reduction in the number of juveniles at the lowest doses tested (LOEC reprod values of 0.3 and 0.2 mg kg -1 of dry soil, respectively) and similar low EC 50 values (fipronil: 0.19 mg kg -1 dry soil, CL 95% 0.16-0.22; ivermectin: 0.43 mg kg -1 dry soil, CL 95% 0.09-0.77), although the effects observed in the former compound were possibly related to a low adult survival (LC 50 of 0.62 mg kg -1 dry soil; CL 95% : 0.25-1.06). For the latter compound no significant lethal effects were observed. Fluazuron caused an intermediate toxicity (EC 50 of 3.07 mg kg -1 dry soil, CL 95% : 2.26-3.87), and also here a decrease in adult survival could explain the effects observed at reproduction. Closantel, despite showing a significant reduction on the number of juveniles produced, no dose-response relationship nor effects higher than 50% were observed. Overall, all tested compounds, especially ivermectin, when present in soil even at sub-lethal concentrations, can impair the reproduction of collembolans and possibly other arthropods. However, the actual risk to arthropod communities should be further investigated performing tests under a more realistic exposure (e.g., by testing the dung itself as the contaminated matrix) and by deriving ecotoxicologically relevant exposure concentration in soil derived from the presence of cattle dung. Copyright © 2017 Elsevier

Effects of soil properties on copper toxicity to earthworm Eisenia fetida in 15 Chinese soils.

Science.gov (United States)

Duan, Xiongwei; Xu, Meng; Zhou, Youya; Yan, Zengguang; Du, Yanli; Zhang, Lu; Zhang, Chaoyan; Bai, Liping; Nie, Jing; Chen, Guikui; Li, Fasheng

2016-02-01

The bioavailability and toxicity of metals in soil are influenced by a variety of soil properties, and this principle should be recognized in establishing soil environmental quality criteria. In the present study, the uptake and toxicity of Cu to the earthworm Eisenia fetida in 15 Chinese soils with various soil properties were investigated, and regression models for predicting Cu toxicity across soils were developed. The results showed that earthworm survival and body weight change were less sensitive to Cu than earthworm cocoon production. The soil Cu-based median effective concentrations (EC50s) for earthworm cocoon production varied from 27.7 to 383.7 mg kg(-1) among 15 Chinese soils, representing approximately 14-fold variation. Soil cation exchange capacity and organic carbon content were identified as key factors controlling Cu toxicity to earthworm cocoon production, and simple and multiple regression models were developed for predicting Cu toxicity across soils. Tissue Cu-based EC50s for earthworm cocoon production were also calculated and varied from 15.5 to 62.5 mg kg(-1) (4-fold variation). Compared to the soil Cu-based EC50s for cocoon production, the tissue Cu-based EC50s had less variation among soils, indicating that metals in tissue were more relevant to toxicity than metals in soil and hence represented better measurements of bioavailability. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of compost and phosphate on plant arsenic accumulation from soils near pressure-treated wood

International Nuclear Information System (INIS)

Cao Xinde; Ma, Lena Q.

2004-01-01

Leaching of arsenic (As) from chromated copper arsenate (CCA)-treated wood may elevate soil arsenic levels. Thus, an environmental concern arises regarding accumulation of As in vegetables grown in these soils. In this study, a greenhouse experiment was conducted to evaluate As accumulation by vegetables from the soils adjacent to the CCA-treated utility poles and fences and examine the effects of soil amendments on plant As accumulation. Carrot (Daucus carota L.) and lettuce (Lactuca sativa L.) were grown for ten weeks in the soil with or without compost and phosphate amendments. As expected, elevated As concentrations were observed in the pole soil (43 mg kg -1 ) and in the fence soil (27 mg kg -1 ), resulting in enhanced As accumulation of 44 mg kg -1 in carrot and 32 mg kg -1 in lettuce. Addition of phosphate to soils increased As accumulation by 4.56-9.3 times for carrot and 2.45-10.1 for lettuce due to increased soil water-soluble As via replacement of arsenate by phosphate in soil. However, biosolid compost application significantly reduced plant As uptake by 79-86%, relative to the untreated soils. This suppression is possibly because of As adsorbed by biosolid organic mater, which reduced As phytoavailability. Fractionation analysis showed that biosolid decreased As in soil water-soluble, exchangeable, and carbonate fraction by 45%, whereas phosphate increased it up to 2.61 times, compared to the untreated soils. Our results indicate that growing vegetables in soils near CCA-treated wood may pose a risk of As exposure for humans. Compost amendment can reduce such a risk by reducing As accumulation by vegetables and can be an important strategy for remediating CCA-contaminated soils. Caution should be taken for phosphate application since it enhances As accumulation. - Capsule: Compost amendment can reduce As exposure risk for humans by reducing As accumulation by vegetables and can be an important strategy for remediating CCA-contaminated soils

Effects of compost and phosphate on plant arsenic accumulation from soils near pressure-treated wood

Energy Technology Data Exchange (ETDEWEB)

Cao Xinde [Soil and Water Science Department, University of Florida, Gainesville, FL (United States)]. E-mail: xcao@stevens.edu; Ma, Lena Q. [Soil and Water Science Department, University of Florida, Gainesville, FL (United States)

2004-12-01

Leaching of arsenic (As) from chromated copper arsenate (CCA)-treated wood may elevate soil arsenic levels. Thus, an environmental concern arises regarding accumulation of As in vegetables grown in these soils. In this study, a greenhouse experiment was conducted to evaluate As accumulation by vegetables from the soils adjacent to the CCA-treated utility poles and fences and examine the effects of soil amendments on plant As accumulation. Carrot (Daucus carota L.) and lettuce (Lactuca sativa L.) were grown for ten weeks in the soil with or without compost and phosphate amendments. As expected, elevated As concentrations were observed in the pole soil (43 mg kg{sup -1}) and in the fence soil (27 mg kg{sup -1}), resulting in enhanced As accumulation of 44 mg kg{sup -1} in carrot and 32 mg kg{sup -1} in lettuce. Addition of phosphate to soils increased As accumulation by 4.56-9.3 times for carrot and 2.45-10.1 for lettuce due to increased soil water-soluble As via replacement of arsenate by phosphate in soil. However, biosolid compost application significantly reduced plant As uptake by 79-86%, relative to the untreated soils. This suppression is possibly because of As adsorbed by biosolid organic mater, which reduced As phytoavailability. Fractionation analysis showed that biosolid decreased As in soil water-soluble, exchangeable, and carbonate fraction by 45%, whereas phosphate increased it up to 2.61 times, compared to the untreated soils. Our results indicate that growing vegetables in soils near CCA-treated wood may pose a risk of As exposure for humans. Compost amendment can reduce such a risk by reducing As accumulation by vegetables and can be an important strategy for remediating CCA-contaminated soils. Caution should be taken for phosphate application since it enhances As accumulation. - Capsule: Compost amendment can reduce As exposure risk for humans by reducing As accumulation by vegetables and can be an important strategy for remediating CCA

High altitude artisanal small-scale gold mines are hot spots for Mercury in soils and plants

International Nuclear Information System (INIS)

Terán-Mita, Tania A.; Faz, Angel; Salvador, Flor; Arocena, Joselito M.; Acosta, Jose A.

2013-01-01

Mercury releases from artisanal and small-scale gold mines (ASGM) condense and settle on plants, soils and water bodies. We collected soil and plant samples to add knowledge to the likely transfer of Hg from soils into plants and eventually predict Hg accumulation in livestock around ASGM in Bolivia. Mean contents of Hg in soils range from 0.5 to 48.6 mg Hg kg −1 soil (5× to 60× more compared to control sites) and exceeded the soil Hg threshold levels in some European countries. The Hg contents ranged from 0.6 to 18 and 0.2 to 28.3 mg Hg kg −1 leaf and root, respectively. The high Hg in Poaceae and Rosaceae may elevate Hg accumulation into the food chain because llama and alpaca solely thrive on these plants for food. Erosion of soils around ASGM in Bolivia contributes to the Hg contamination in lower reaches of the Amazon basin. - Highlights: ► Hg in soils ranged from 0.5 to 48.6 mg Hg kg −1 soil, and at least 5× to 60× more than control sites. ► Plants near gold mines exceed the 0.1 mg Hg kg −1 plant material European limit for feed quality. ► Camelids feeding on plants with high Hg may elevate Hg levels in foods (meats) for the miners. ► Soils with high Hg can be significant Hg sources to the contamination of the Amazon basin. - Mean contents of Hg in soils were at least 5× to 60× more compared to Hg in control sites, and the high Hg in Poaceae and Rosaceae may elevate Hg into the food chain.

In situ biosurfactant production and hydrocarbon removal by Pseudomonas putida CB-100 in bioaugmented and biostimulated oil-contaminated soil

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Martínez-Toledo Ángeles

2013-01-01

Full Text Available In situ biosurfactant (rhamnolipid production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus, P. putida addition, and addition of both (P. putida and nutrients. The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54; p < 0.019 between TPH concentration (mg/kg and surface tension (mN/m, When both bacteria and nutrients were involved, TPH levels were lowered to 33.7%, and biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension, and a correlation between bacterial growth and biosurfactant production (R = -0.64; p < 0.009 was observed. When the nutrients and P. putida were added, TPH removal was 61.1%, 1.85 mg/kg of biosurfactants were produced, and the surface tension was 55.6 mN/m. In summary, in irradiated and non-irradiated soils, in situ rhamnolipid production by P. putida enhanced TPH decontamination of the soil.

Integrated micro-biochemical approach for phytoremediation of cadmium and zinc contaminated soils.

Science.gov (United States)

Mani, Dinesh; Kumar, Chitranjan; Patel, Niraj Kumar

2015-01-01

The integrated potential of oilcake manure (OM), elemental sulphur (S(0)), Glomus fasciculatum and Pseudomonas putida by growing Helianthus annuus L for phytoremediation of cadmium and zinc contaminated soils was investigated under pot experiment. The integrated treatment (2.5 g kg(-1) OM, 0.8 g kg(-1) S(0) and co-inoculation with G. fasciculatum and P. putida promoted the dry biomass of the plant. The treatment was feasible for enhanced cadmium accumulation up to 6.56 and 5.25 mg kg(-1) and zinc accumulation up to 45.46 and 32.56 mg kg(-1) in root and shoot, respectively, which caused maximum remediation efficiency (0.73 percent and 0.25 percent) and bioaccumulation factor (2.39 and 0.83) for Cd and Zn, respectively showing feasible uptake (in mg kg(-1) dry biomass) of Cd (5.55) and Zn (35.51) at the contaminated site. Thus, authors conclude to integrate oilcake manure, S(0) and microbial co-inoculation for enhanced clean-up of cadmium and zinc-contaminated soils. Copyright © 2014 Elsevier Inc. All rights reserved.

Aqueous biphasic extraction of uranium and thorium from contaminated soils. Final report

International Nuclear Information System (INIS)

Chaiko, D.J.; Gartelmann, J.; Henriksen, J.L.; Krause, T.R.; Deepak; Vojta, Y.; Thuillet, E.; Mertz, C.J.

1995-07-01

The aqueous biphasic extraction (ABE) process for soil decontamination involves the selective partitioning of solutes and fine particulates between two immiscible aqueous phases. The biphase system is generated by the appropriate combination of a water-soluble polymer (e.g., polyethlene glycol) with an inorganic salt (e.g., sodium carbonate). Selective partitioning results in 99 to 99.5% of the soil being recovered in the cleaned-soil fraction, while only 0.5 to 1% is recovered in the contaminant concentrate. The ABE process is best suited to the recovery of ultrafine, refractory material from the silt and clay fractions of soils. During continuous countercurrent extraction tests with soil samples from the Fernald Environmental Management Project site (Fernald, OH), particulate thorium was extracted and concentrated between 6- and 16-fold, while the uranium concentration was reduced from about 500 mg/kg to about 77 mg/kg. Carbonate leaching alone was able to reduce the uranium concentration only to 146 mg/kg. Preliminary estimates for treatment costs are approximately $160 per ton of dry soil. A detailed flowsheet of the ABE process is provided

Geochemical and isotopic study of soils and waters from an Italian contaminated site: Agro Aversano (Campania)

Science.gov (United States)

Bove, M.A.; Ayuso, R.A.; de Vivo, B.; Lima, A.; Albanese, S.

2011-01-01

Lead isotope applications have been widely used in recent years in environmental studies conducted on different kinds of sampled media. In the present paper, Pb isotope ratios have been used to determine the sources of metal pollution in soils and waters in the Agro Aversano area. During three different sampling phases, a total of 113 surface soils (5-20. cm), 20 samples from 2 soil profiles (0-1. m), 11 stream waters and 4 groundwaters were collected. Major element concentrations in sampled media have been analyzed by the ICP-MS technique. Surface soils (20 samples), all soil profiles and all waters have been also analyzed for Pb isotope compositions by thermal ionization (TIMS). The geochemical data were assessed using statistic methods and cartographically elaborated in order to have a clear picture of the level of disturbance of the area. Pb isotopic data were studied to discriminate between anthropogenic and geologic sources. Our results show that As (5.6-25.6. mg/kg), Cu (9-677. mg/kg), Pb (22-193. mg/kg), Tl (0.53-3.62. mg/kg), V (26-142. mg/kg) and Zn (34-215. mg//kg) contents in analyzed soils, exceed the intervention limits fixed by the Italian Environmental Law for residential areas in some of the sampled sites, while intervention limit for industrial areas is exceeded only for Cu concentrations. Lead isotopic data, show that there is a high similarity between the ratios measured in the leached soil samples and those deriving from anthropic activities. This similarity with anthropogenic Pb is also evident in the ratios measured in both groundwater and stream water samples. ?? 2010 Elsevier B.V.

Feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS) to quantify iron-cyanide (Fe-CN) complexes in soil

Science.gov (United States)

Sut-Lohmann, Magdalena; Raab, Thomas

2017-04-01

Contaminated sites create a significant risk to human health, by poisoning drinking water, soil, air and as a consequence food. Continuous release of persistent iron-cyanide (Fe-CN) complexes from various industrial sources poses a high hazard to the environment and indicates the necessity to analyze considerable amount of samples. At the present time quantitative determination of Fe-CN concentration in soil usually requires a time consuming two step process: digestion of the sample (e.g., micro distillation system) and its analytical detection performed, e.g., by automated spectrophotometrical flow injection analysis (FIA). In order to determine the feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS) to quantify the Fe-CN complexes in soil matrix, 42 soil samples were collected (8 to 12.520 mg kg-1CN) indicating single symmetrical CN band in the range 2092 - 2084 cm-1. Partial least squares (PLS) calibration-validation model revealed IR response to CNtot exceeding 1268 mg kg-1 (limit of detection, LOD). Subsequently, leave-one-out cross-validation (LOO-CV) was performed on soil samples containing low CNtot (900 mg kg-1 resulted in LOD equal to 3494 mg kg-1. Our results indicate that spectroscopic data in combination with PLS statistics can efficiently be used to predict Fe-CN concentrations in soil. We conclude that the protocol applied in this study can strongly reduce the time and costs essential for the spatial and vertical screening of the site affected by complexed Fe-CN.

Biological indicators capable of assessing thermal treatment efficiency of hydrocarbon mixture-contaminated soil.

Science.gov (United States)

Wang, Jiangang; Zhan, Xinhua; Zhou, Lixiang; Lin, Yusuo

2010-08-01

In China, there are many special sites for recycling and washing the used drums, which release a variety of C5-C40 hydrocarbon mixture into the soil around the site. The remediation of these contaminated sites by thermal treatment is adopted ubiquitously and needs to be assessed. Here we report the feasibility of biological indicators applied to assess thermal treatment efficiency in such contaminated soil. A series of biological indicators, including seed germination index (SGI), root elongation index (REI), plant growth height, biomass, carbon dioxide evolved (CDE), soil respiration inhibition (SRI) and soil enzymatic activities, were employed to monitor or assess hydrocarbon mixture removal in thermal treated soil. The results showed that residual hydrocarbon mixture content correlated strongly negatively with SGI for sesamum (Sesamum indicum L.), plant height, and biomass for ryegrass (Lolium perenne L.) in the concentration ranges of 0-3990, 0-3170 and 0-2910 mg kg(-1), respectively. In contrast, REI for sesamum was positively correlated with residual hydrocarbon mixture content from 0 to 1860 mg kg(-1). In addition, both CDE and SRI demonstrated that 600 mg kg(-1) of residual hydrocarbon mixture content caused the highest amount of soil carbon dioxide emission and inhabitation of soil respiration. The results of soil enzymes indicated that 1000 mg kg(-1) of residual hydrocarbon mixture content was the threshold value of stimulating or inhibiting the activities of phosphatase and catalase, or completely destroying the activities of dehydrogenase, invertase, and urease. In conclusion, these biological indicators can be used as a meaningful complementation for traditional chemical content measurement in evaluating the environmental risk of the contaminated sites before and after thermal treatment. (c) 2010 Elsevier Ltd. All rights reserved.

Desirable levels of exchangeable K and Ca and their concentration in the soil solution to reduce uptake of radioactive Cs by rice plants

International Nuclear Information System (INIS)

Sekimoto, Hitoshi; Yamada, Takashi; Hotsuki, Tomoe; Matsuzaki, Akio; Mimura, Tetsuro

2014-01-01

K in the soil solution can control the uptake of radioactive Cs by rice plants, but this control is not accomplished only by K; it is affected by other ionic species. It is therefore important to investigate uptake of radioactive Cs from the perspective of the concentration of major cations such as Ca in the soil solution and the levels of exchangeable cations in the soil. To clarify the effects of K and Ca in the soil solution and of the levels of soil exchangeable cations to prevent uptake of radioactive Cs, we conducted a pot experiment and field experiments in a paddy soil in 2011 and 2012. To reduce the uptake of radioactive Cs, it was necessary to achieve a K concentration in the soil solution of 0.5 mmol L"-"1, and a Ca concentration higher than 2 mmol L"-"1 based on the results of the pot experiment. In addition, we obtained the desirable levels of exchangeable cations and the cation exchange capacity (CEC) in the soil from previous reports and the results of our field experiments. On this basis, we propose the following threshold levels for exchangeable cations and CEC in the soil as a standard: 0.53 K cmol_c kg"-"1, 18.0 Ca cmol_c kg"-"1, 2.0 Mg cmol_c kg"-"1, i.e. 25 mg K_2O 100 g"-"1, 505 mg CaO 100 g"-"1, 40 Mg O mg 100 g"-"1, and a CEC of 30 cmol_c kg"-"1. Converting these values into the corresponding levels in the soil solution, we obtained concentrations of 0.71 mmol K L"-"1, 4.22 mmol Ca L"-"1, and 1.35 mmol Mg L"-"1. These levels are within the improving standard for fertility of paddy soils in Japan. Consequently, it will be necessary to improve the fertility of paddy soils to control the uptake of radioactive Cs by rice plants. (author)

Translocation of iodine-129 in soil and transfer to vegetation

International Nuclear Information System (INIS)

Handl, J.

1989-01-01

The translocation of I-129 in the soil and its long-term transfer from soil to plant have been investigated using an undisturbed soil column and a pasture on a river bank. The I-129 profiles in the soils of the monolith and the pasture exhibit clear differences in the distribution of radioiodine after 52 and 47 months, respectively. At those times after surface contamination of both soil types 88% (monolith) and 66% (pasture) of the total I-129 activity were found in the top soil layer of 10 cm, indicating that translocation in the pasture soil is faster than in the monolith. Apart from soil-specific parameters this behaviour may be explained by anaerobic conditions created in the soil due to high water levels in the nearby river attecting the chemical form of iodine. The distribution of stable iodine was found rather homogeneous in both soils with mean contents of 3 mg I-127 kg -1 d.w. in the upper 15 cm and 4 mg I-127 kg -1 d.w. in deeper layers in case of the monolith. For the pasture soil the corresponding values are about 4 and 5 mg I-127 kg -1 d.w. Transfer factors plant/soil (dry weight basis) of I-129 obtained from the monolith 39 g and 52 months after contamination are 1.5x10 -3 and 2.1x10 -3 , respectively. Data from the pasture 35 and 47 months after contamination show values of 9.0x10 -3 and 8.4x10 -3 , respectively. Transfer factors of stable iodine are significantly higher in both soils yielding an average value of 1.0 for the monolith and 0.3 for the pasture. Delay constants (related to a top soil layer of 10 cm) calculated for I-129 using data obtained from the long-term translocation processes to deeper soil layers in the monolith and in the pasture show values of 1x10 -9 s -1 and 4x10 -9 s -1 , respectively. (orig.) [de

Effects of soil type and genotype on lead concentration in rootstalk vegetables and the selection of cultivars for food safety.