Sample records for acid soil amended

  1. Effect of Soil Amendments on Microbial Resilience Capacity of Acid Soil Under Copper Stress.

    PubMed

    Mounissamy, Vassanda Coumar; Kundu, Samaresh; Selladurai, Rajendiran; Saha, Jayanta Kumar; Biswas, Ashish Kumar; Adhikari, Tapan; Patra, Ashok Kumar

    2017-11-01

    An incubation study was undertaken to study microbial resilience capacity of acid soil amended with farmyard manure (FYM), charcoal and lime under copper (Cu) perturbation. Copper stress significantly reduced enzymatic activities and microbial biomass carbon (MBC) in soil. Percent reduction in microbial activity of soil due to Cu stress was 74.7% in dehydrogenase activity, 59.9% in MBC, 48.2% in alkaline phosphatase activity and 15.1% in acid phosphatase activity. Soil treated with FYM + charcoal showed highest resistance index for enzymatic activities and MBC. Similarly, the highest resilience index for acid phosphatase activity was observed in soil amended with FYM (0.40), whereas FYM + charcoal-treated soil showed the highest resilience indices for alkaline, dehydrogenase activity and MBC: 0.50, 0.22 and 0.25, respectively. This investigation showed that FYM and charcoal application, either alone or in combination, proved to be better than lime with respect to microbial functional resistance and resilience of acid soil under Cu perturbation.

  2. Effect of carbonaceous soil amendments on potential mobility of weak acid herbicides in soil

    USDA-ARS?s Scientific Manuscript database

    Use of carbonaceous amendments in soil has been proposed to decrease potential offsite transport of weak acid herbicides and metabolites by increasing their sorption to soil. The effects of organic olive mill waste, biochars from different feed stocks, and humic acid bound to clay on sorption of MCP...

  3. Improving Phosphorus Availability in an Acid Soil Using Organic Amendments Produced from Agroindustrial Wastes

    PubMed Central

    Ch'ng, Huck Ywih; Ahmed, Osumanu Haruna; Majid, Nik Muhamad Ab.

    2014-01-01

    In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp.) to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus), and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments. PMID:25032229

  4. Screening and assessment of solidification/stabilization amendments suitable for soils of lead-acid battery contaminated site.

    PubMed

    Zhang, Zhuo; Guo, Guanlin; Teng, Yanguo; Wang, Jinsheng; Rhee, Jae Seong; Wang, Sen; Li, Fasheng

    2015-05-15

    Lead exposure via ingestion of soil and dust generally occurs at lead-acid battery manufacturing and recycling sites. Screening solidification/stabilization (S/S) amendments suitable for lead contaminated soil in an abandoned lead-acid battery factory site was conducted based on its chemical forms and environmental risks. Twelve amendments were used to immobilize the Pb in soil and assess the solidification/stabilization efficiency by toxicity leaching tests. The results indicated that three amendments, KH₂PO₄ (KP), KH₂PO₄:oyster shell power=1:1 (by mass ratio; SPP), and KH₂PO₄:sintered magnesia=1:1 (by mass ratio; KPM) had higher remediation efficiencies that led to a 92% reduction in leachable Pb with the addition of 5% amendments, while the acid soluble fraction of Pb (AS-Pb) decreased by 41-46% and the residual fraction (RS-Pb) increased by 16-25%. The S/S costs of the three selected amendments KP, SPP, and KPM could be controlled to $22.3 per ton of soil when the Pb concentration in soil ranged from 2000 to 3000 mg/kg. The results of this study demonstrated that KP, SPP, and KPM can effectively decrease bioavailability of Pb. These findings could provide basis for decision-making of S/S remediation of lead-acid battery contaminated sites. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. The Effects of Various Amendments on Trace Element Stabilization in Acidic, Neutral, and Alkali Soil with Similar Pollution Index

    PubMed Central

    Kim, Min-Suk; Min, Hyun-Gi; Lee, Sang-Hwan; Kim, Jeong-Gyu

    2016-01-01

    Many studies have examined the application of soil amendments, including pH change-induced immobilizers, adsorbents, and organic materials, for soil remediation. This study evaluated the effects of various amendments on trace element stabilization and phytotoxicity, depending on the initial soil pH in acid, neutral, and alkali conditions. As in all types of soils, Fe and Ca were well stabilized on adsorption sites. There was an effect from pH control or adsorption mechanisms on the stabilization of cationic trace elements from inorganic amendments in acidic and neutral soil. Furthermore, acid mine drainage sludge has shown great potential for stabilizing most trace elements. In a phytotoxicity test, the ratio of the bioavailable fraction to the pseudo-total fraction significantly affected the uptake of trace elements by bok choy. While inorganic amendments efficiently decreased the bioavailability of trace elements, significant effects from organic amendments were not noticeable due to the short-term cultivation period. Therefore, the application of organic amendments for stabilizing trace elements in agricultural soil requires further study. PMID:27835687

  6. The Effects of Various Amendments on Trace Element Stabilization in Acidic, Neutral, and Alkali Soil with Similar Pollution Index.

    PubMed

    Kim, Min-Suk; Min, Hyun-Gi; Lee, Sang-Hwan; Kim, Jeong-Gyu

    2016-01-01

    Many studies have examined the application of soil amendments, including pH change-induced immobilizers, adsorbents, and organic materials, for soil remediation. This study evaluated the effects of various amendments on trace element stabilization and phytotoxicity, depending on the initial soil pH in acid, neutral, and alkali conditions. As in all types of soils, Fe and Ca were well stabilized on adsorption sites. There was an effect from pH control or adsorption mechanisms on the stabilization of cationic trace elements from inorganic amendments in acidic and neutral soil. Furthermore, acid mine drainage sludge has shown great potential for stabilizing most trace elements. In a phytotoxicity test, the ratio of the bioavailable fraction to the pseudo-total fraction significantly affected the uptake of trace elements by bok choy. While inorganic amendments efficiently decreased the bioavailability of trace elements, significant effects from organic amendments were not noticeable due to the short-term cultivation period. Therefore, the application of organic amendments for stabilizing trace elements in agricultural soil requires further study.

  7. Interactions between organic amendments and phosphate fertilizers modify phosphate sorption processes in an acid soil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sckefe, C.R.; Patti, A.F.; Clune, T.S.

    2008-07-15

    To determine how organic amendments and phosphate fertilizers interact to modify P sorption processes, three phosphate fertilizers were applied to lignite- and compost-amended acid soil and incubated for either 3 or 26 days. The fertilizers applied were potassium dihydrogen phosphate, triple superphosphate, and diammonium phosphate (DAP). After 3 days of incubation, sorption of all three P sources was decreased in the lignite-amended treatments, whereas P sorption was increased in the compost-amended treatments. Increased incubation time (26 days) resulted in significantly decreased P sorption when DAP was added to lignite-amended treatments. Addition of triple superphosphate increased P sorption in lignite- andmore » compost-amended treatments and decreased solution pH compared with DAP application. In addition to the effect of P source, differences in P sorption between the lignite- and compost-amended treatments were driven by differences in solution chemistry, predominantly solution pH and cation dynamics. Soil amendment and fertilizer addition also increased microbial activity in the incubation systems, as measured by carbon dioxide respiration. It is proposed that the combination of lignite and DAP may contribute to decreased P sorption in acid soils, with the positive effects likely caused by both chemical and biological processes, including the formation of soluble organic-metal complexes.« less

  8. Reduced nitrification and abundance of ammonia-oxidizing bacteria in acidic soil amended with biochar.

    PubMed

    Wang, Zhenyu; Zong, Haiying; Zheng, Hao; Liu, Guocheng; Chen, Lei; Xing, Baoshan

    2015-11-01

    Adding biochar into soils has potential to manipulate soil nitrification process due to its impacts on nitrogen (N) cycling, however, the exact mechanisms underlying the alteration of nitrification process in soils are still not clear. Nitrification in an acidic orchard soil amended with peanut shell biochar (PBC) produced at 400 °C was investigated. Nitrification was weakened by PBC addition due to the decreased NH4(+)-N content and reduced ammonia-oxidizing bacteria (AOB) abundance in PBC-amended soils. Adding phenolic compounds (PHCs) free biochar (PBC-P) increased the AOB abundance and the DGGE band number, indicating that PHCs remaining in the PBC likely reduced AOB abundance and diversity. However, PBC addition stimulated rape growth and increased N bioavailability. Overall, adding PBC could suppress the nitrification process and improve N bioavailability in the agricultural soils, and thus possibly mitigate the environmental negative impacts and improving N use efficiency in the acidic soils added with N fertilizer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Effect of ageing on the availability of heavy metals in soils amended with compost and biochar: evaluation of changes in soil and amendment properties.

    PubMed

    Venegas, A; Rigol, A; Vidal, M

    2016-10-01

    Remediation strategies using soil amendments should consider the time dependence of metal availability to identify amendments that can sustainably reduce available pollutant concentrations over time. Drying-wetting cycles were applied on amendments, soils and soil + amendment mixtures, to mimic ageing at field level and investigate its effect on extractable Cd, Cu, Ni, Pb and Zn concentrations from three contaminated soils. The amendments investigated were municipal waste organic compost and biochars. The amendments, soils and mixtures were characterised by their physicochemical properties at different ageing times. The amendments were also characterised in terms of sorption capacity for Cd and Cu. The sorption capacity and the physicochemical properties of the amendments remained constant over the period examined. When mixed with the soils, amendments, especially the compost, immediately reduced the extractable metals in the soils with low pH and acid neutralisation capacity, due to the increase in pH and buffering capacity of the mixtures. The amendments had a relatively minor impact on the metal availability concentrations for the soil with substantially high acid neutralisation capacity. The most important changes in extractable metal concentrations were observed at the beginning of the experiments, ageing having a minor effect on metal concentrations when compared with the initial effect of amendments.

  10. Pyrene fate affected by humic acid amendment in soil slurry systems.

    PubMed

    Liang, Yanna; Sorensen, Darwin L; McLean, Joan E; Sims, Ronald C

    2008-09-10

    Humic acid (HA) has been found to affect the solubility, mineralization, and bound residue formation of polycyclic aromatic hydrocarbons (PAHs). However, most of the studies on the interaction between HA and PAH concentrated on one or two of the three phases. Few studies have provided a simple protocol to demonstrate the overall effects of HA on PAH distribution in soil systems for all three phases. In this study, three doses of standard Elliott soil HA (ESHA), 15, 187.5, and 1,875 mug ESHA/g soil slurry, were amended to soil slurry systems. 14C-pyrene was added to the systems along with non-radiolabeled pyrene; 14C and 14CO2 were monitored for each system for a period of 120 days. The highest amendment dose significantly increased the 14C fraction in the aqueous phase within 24 h, but not after that time. Pyrene mineralization was significantly inhibited by the highest dose over the 120-day study. While organic solvent extractable 14C decreased with time in all systems, non-extractable or bound 14C was significantly enhanced with the highest dose of ESHA addition. Amendment of the highest dose of ESHA to pyrene contaminated soil was observed to have two major functions. The first was to mitigate CO2 production significantly by reducing 14CO2 from 14C pyrene mineralization. The second was to significantly increase stable bound 14C formation, which may serve as a remediation end point. Overall, this study demonstrated a practical approach for decontamination of PAH contaminated soil. This approach may be applicable to other organic contaminated environments where active bioremediation is taking place.

  11. Growth and Cd uptake by rice (Oryza sativa) in acidic and Cd-contaminated paddy soils amended with steel slag.

    PubMed

    He, Huaidong; Tam, Nora F Y; Yao, Aijun; Qiu, Rongliang; Li, Wai Chin; Ye, Zhihong

    2017-12-01

    Contamination of rice (Oryza sativa) by Cd is of great concern. Steel slag could be used to amend Cd-contaminated soils and make them safe for cereal production. This work was conducted to study the effects of steel slag on Cd uptake and growth of rice plants in acidic and Cd-contaminated paddy soils and to determine the possible mechanisms behind these effects. Pot (rhizobag) experiments were conducted using rice plants grown on two acidic and Cd-contaminated paddy soils with or without steel slag amendment. Steel slag amendment significantly increased grain yield by 36-45% and root catalase activity, and decreased Cd concentrations in brown rice by 66-77% compared with the control, in both soils. Steel slag amendment also markedly decreased extractable soil Cd, Cd concentrations in pore-water and Cd translocation from roots to above-ground parts. It also significantly increased soil pH, extractable Si and Ca in soils and Ca concentrations in roots. Significant positive correlations were found between extractable soil Cd and Cd concentrations in rice tissues, but it was negatively correlated with soil pH and extractable Si. Calcium in root tissues significantly and negatively correlated with Cd translocation factors from roots to straw. Overall, steel slag amendment not only significantly promoted rice growth but decreased Cd accumulation in brown rice. These benefits appear to be related to improvements in soil conditions (e.g. increasing pH, extractable Si and Ca), a reduction in extractable soil Cd, and suppression of Cd translocation from roots to above-ground parts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Soil amendments promote vegetation establishment and control acidity in coal combustion waste

    Treesearch

    R.M. Danker; D.C. Adriano; Bon-Jun Koo; C.D. Barton

    2003-01-01

    The effects of adding various soil amendments and a pyrite oxidation inhibitor to aid in the establishment of vegetation and to reduce acid drainage (AD) from coal fly ash and coal reject (FA + CR*) were assessed in an outdoor mesocosm study. Preliminary greenhouse experiments and field observations at the U.S. Department of Energy's Savannah River Site (SRS)...

  13. Modulation of hexavalent chromium toxicity on Οriganum vulgare in an acidic soil amended with peat, lime, and zeolite.

    PubMed

    Antoniadis, Vasileios; Zanni, Anna A; Levizou, Efi; Shaheen, Sabry M; Dimirkou, Anthoula; Bolan, Nanthi; Rinklebe, Jörg

    2018-03-01

    Dynamics of chromate (Cr(VI)) in contaminated soils may be modulated by decreasing its phytoavailability via the addition of organic matter-rich amendments, which might accelerate Cr(VI) reduction to inert chromite (Cr(III)) or high-cation exchange capacity amendments. We studied Cr(VI) phytoavailability of oregano in a Cr(VI)-spiked acidic soil non-treated (S) and treated with peat (SP), lime (SL), and zeolite (SZ). The addition of Cr(VI) increased the concentrations of Cr(VI) and Cr(III) in soils and plants, especially in the lime-amended soil. The plant biomass decreased in the lime-amended soil compared to the un-spiked soil (control) due to decreased plant phosphorus concentrations and high Cr(VI) concentrations in root at that treatment. Oregano in the peat-amended soil exhibited significantly less toxic effects, due to the role of organic matter in reducing toxic Cr(VI) to Cr(III) and boosted plant vigour in this treatment. In the lime-amended soil, the parameters of soil Cr(VI), soil Cr(III), and root Cr(III) increased significantly compared to the non-amended soil, indicating that Cr(VI) reduction to Cr(III) was accelerated at high pH. Added zeolite failed to decreased Cr(VI) level to soil and plant. Oregano achieved a total uptake of Cr(III) and Cr(VI) of 0.275 mg in plant kg -1 soil in a pot in the non-amended soil. We conclude that peat as soil amendment might be considered as a suitable option for decreasing Cr(VI) toxicity in soil and plant, and that oregano as tolerant plant species has a certain potential to be used as a Cr accumulator. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Soil amino compound and carbohydrate contents influenced by organic amendments

    USDA-ARS?s Scientific Manuscript database

    Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might af...

  15. Effects of cadmium amendments on low-molecular-weight organic acid exudates in rhizosphere soils of tobacco and sunflower.

    PubMed

    Chiang, Po-Neng; Wang, Ming Kuang; Chiu, Chih Yu; Chou, Shu-Yen

    2006-10-01

    To recognize physiological response of plants to cadmium (Cd) toxicity in rhizosphere of plants, the pot experiments were employed to investigate how low-molecular-weight organic acids (LMWOAs) were exudated from tobacco and sunflower roots of Cd-amended soils. The aims of this study were to assess the effect of LMWOAs on uptake of Cd by tobacco and sunflower under pot experiments, thus comparing the ability of tobacco and sunflower for phytoremediation. Surface soils (0-20 cm) were collected from Taichung Experiment Station (TC) (silty loam). Cadmium chloride (CdCl(2)) was amended into TC soil, giving Cd concentrations of 1, 5, 10 mg kg(-1) soil. Soils with different concentrations of Cd were put into 12 cm (i.d.) pots for incubation, and then 2-week-old tobacco and sunflower seedlings were transplanted into the pots. Tobacco and sunflower were grown in greenhouse for 50 days, respectively. The rhizosphere and bulk soils, and fresh plant tissues were collected after harvest. The Cd concentrations in the plant and transfer factor values in the sunflower were higher than that in the tobacco. No LMWOAs were detected by gas chromatograph in bulk soils, and low amounts of LMWOAs were found in uncontaminated rhizosphere soils. Acetic, lactic, glycolic, malic, maleic, and succinic acids were found in the tobacco and sunflower rhizosphere soils. Concentrations of LMWOAs increased with increasing amendment of Cd concentrations in tobacco and sunflower rhizosphere soils. Correlation coefficient (r) of concentrations of Cd amendment versus LMWOAs exudates of tobacco and sunflower were 0.85 and 0.98, respectively. These results suggest that the different levels of LMWOAs present in the rhizosphere soil play an important role in the solubilization of Cd that bound with soil particle into soil solution and then uptake by plants.

  16. Sorption of polar herbicides and herbicide metabolites by biochar-amended soil.

    PubMed

    Dechene, Annika; Rosendahl, Ingrid; Laabs, Volker; Amelung, Wulf

    2014-08-01

    Biochar-amended soil has been proven to possess superior sorption capacities for several environmental pollutants compared with pure soil. However, the role of biochar in the immobilization of polar pesticides and their metabolites has hardly been tested. The aim of this study was therefore to investigate the effect of a soil amendment with biochar on the sorption of selected polar herbicides and herbicide metabolites (log Kow 0.3-<2). To simulate worst-case sorption, a sandy soil (1.7% organic matter) was amended with 1.5% biochar (fresh or composted) to determine sorption/desorption isotherms of the test compounds. One herbicide (imazamox) and three herbicide metabolites (methyl-desphenyl-chloridazon, metazachlor oxalic acid, metazachlor sulfonic acid) were tested, i.e. three anionic and one neutral polar compound. The results showed that the presence of biochar increased the sorption capacity of the soil only in the case of the uncharged compound methyl-desphenyl-chloridazon, for which the average distribution coefficients in biochar-amended soils were higher than in pure soil by a factor of 2.1-2.5. However, this effect rather seemed to reflect the increased soil organic carbon content after the addition of biochar than a preferred sorption of methyl-desphenyl-chloridazon to biochar. In the case of the three anionic compounds imazamox, metazachlor oxalic acid and metazachlor sulfonic acid, biochar amendment did not increase the sorption capacity of the soil for these compounds, presumably as a result of its negative net charge. Similarly, desorption experiments did not show any significant effect of the biochar amendment on desorption. This suggests that the potential of using biochar to mitigate the leaching of the tested polar pesticides or metabolites is limited. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils

    EPA Science Inventory

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.d...

  18. Alum amendment effects on phosphorus release and distribution in poultry litter-amended sandy soils

    USGS Publications Warehouse

    Staats, K.E.; Arai, Y.; Sparks, D.L.

    2004-01-01

    Increased poultry production has contributed to excess nutrient problems in Atlantic Coastal Plain soils due to land application of poultry litter (PL). Aluminum sulfate [alum, Al2(SO4)3?? 14H2O] amendment of PL effectively reduces soluble phosphorus (P) in the PL; however, the effects of these litters when added to acidic, sandy soils are not well understood. The objective of this study was to investigate the efficacy of alum-amended poultry litter in reducing P release from three Delaware Coastal Plain soils: Evesboro loamy sand (Ev; excessively drained, mesic, coated Typic Quartzipsamments), Rumford loamy sand (Ru; well drained, coarse-loamy, siliceous, subactive, thermic Typic Hapludults), and Pocomoke sandy loam (Pm; very poorly drained, coarse-loamy, siliceous, active, thermic Typic Umbraquults). Long-term (25 d) and short-term (24 h) desorption studies were conducted, in addition to chemical extractions and kinetic modeling, to observe the changes that alum-amended versus unamended PL caused in the soils. The Ev, Ru, and Pm soils were incubated with 9 Mg ha-1 of alum-amended or unamended PL. Long-term desorption (25 d) of the incubated material resulted in approximately 13.5% (Ev), 12.7% (Ru), and 13.3% (Pm) reductions in cumulative P desorbed when comparing soil treated with unamended and alum-amended PL. In addition, the P release from the soil treated with alum-amended litter was not significantly different from the control (soil alone). Short-term desorption (24 h) showed 7.3% (Ev), 15.4% (Ru), and 20% (Pm) reductions. The overall implication from this study is that the use of alum as a PL amendment is useful in coarse-textured soils of the Coastal Plain. With increased application of alum-amended PL, more significant decreases may be possible with little or no effect on soil quality.

  19. Amendment damages the function of continuous flooding in decreasing Cd and Pb uptake by rice in acid paddy soil.

    PubMed

    Ye, Xinxin; Li, Hongying; Zhang, Ligan; Chai, Rushan; Tu, Renfeng; Gao, Hongjian

    2018-01-01

    Combinations of remediation technologies are needed to solve the problem of soil contamination in paddy rice, due to multiple potential toxic elements (PTEs). Two potential mitigation methods, water management and in-situ remediation by soil amendment, have been widely used in treatment of PTE-polluted paddy soil. However, the interactive relationship between soil amendment and water management, and its influence on the accumulation of PTEs in rice are poorly understood. Greenhouse pot experiments were conducted to examine the effects of phosphate amendment on Cd and Pb availability in soil and their influence on Cd and Pb uptake into rice, on Fe and P availability in soil, and on the alteration of Fe amount and compartment on root surface among different water management strategies. Results indicated that Cd and Pb content in the shoot and grain were significantly affected by the different water management strategies in nonamended soils, and followed the order: wetting irrigation > conventional irrigation > continuous flooding. The application of phosphate amendment significantly decreased the variations of Cd and Pb absorption in shoot and grain of rice among different water treatments. The reasons may be attributed to the enhancement of P availability and the decrease of Fe availability in soil, and the decreased variations of Fe 2+ /Fe 3+ content in root coating after the application of phosphate amendment. These results suggested that the simultaneous use of phosphate amendment and continuous flooding to immobilize Cd and Pb, especially in acid paddy soils, should be avoided. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Phytotoxicity of citric acid and Tween® 80 for potential use as soil amendments in enhanced phytoremediation.

    PubMed

    Agnello, A C; Huguenot, D; van Hullebusch, E D; Esposito, G

    2015-01-01

    Enhanced phytoremediation adding biodegradable amendments like low molecular weight organic acids and surfactants is an interesting area of current research to overcome the limitation that represents low bioavailability of pollutants in soils. However, prior to their use in assisted phytoremediation, it is necessary to test if amendments per se exert any toxic effect to plants and to optimize their application mode. In this context, the present study assessed the effects of citric acid and Tween® 80 (polyethylene glycol sorbitan monooleate) on the development of alfalfa (Medicago sativa) plants, as influenced by their concentration and frequency of application, in order to evaluate the feasibility for their future use in enhanced phytoremediation of multi-contaminated soils. The results showed that citric acid negatively affected plant germination, while it did not have any significant effect on biomass or chlorophyll content. In turn, Tween® 80 did not affect plant germination and showed a trend to increase biomass, as well as it did not have any significant effect on chlorophyll levels. M. sativa appeared to tolerate citric acid and Tween® 80 at the tested concentrations, applied weekly. Consequently, citric acid and Tween® 80 could potentially be utilized to assist phytoremediation of contaminated soils vegetated with M. sativa.

  1. Stability of immobilization remediation of several amendments on cadmium contaminated soils as affected by simulated soil acidification.

    PubMed

    Guo, Fuyu; Ding, Changfeng; Zhou, Zhigao; Huang, Gaoxiang; Wang, Xingxiang

    2018-06-04

    Chemical immobilization is a practical approach to remediate heavy metal contamination in agricultural soils. However, the potential remobilization risks of immobilized metals are a major environmental concern, especially in acid rain zones. In the present study, changes in the immobilization efficiency of several amendments as affected by simulated soil acidification were investigated to evaluate the immobilization remediation stability of several amendments on two cadmium (Cd) contaminated soils. Amendments (hydrated lime, hydroxyapatite and biochar) effectively immobilized Cd, except for organic fertilizer, and their immobilizations were strongly decreased by the simulated soil acidification. The ratio of changes in CaCl 2 -extractable Cd: pH (△CaCl 2 -Cd/△pH) can represent the Cd remobilization risk of different amended soils. Hydroxyapatite and biochar had a stronger durable immobilizing effect than did hydrated lime, particularly in soil with a lower pH buffering capacity, which was further confirmed by the Cd concentration and accumulation in lettuce. These results can be attributed to that hydroxyapatite and biochar transformed greater proportions of exchangeable Cd to other more stable fractions than lime. After 48 weeks of incubation, in soil with a lower pH buffering capacity, the immobilization efficiencies of lime, hydroxyapatite, biochar and organic fertilizer in the deionized water group (pH 6.5) were 71.7%, 52.7%, 38.6% and 23.9%, respectively, and changed to 19.1%, 33.6%, 26.5% and 5.0%, respectively, in the simulated acid rain group (pH 2.5). The present study provides a simple method to preliminarily estimate the immobilization efficiency of amendments and predict their stability in acid rain regions before large-scale field application. In addition, hydrated lime is recommended to be combined with other acid-stable amendments (such as hydroxyapatite or biochar) to remediate heavy metal-contaminated agricultural soils in acid precipitation

  2. Phytoremediation of Cu and Zn by vetiver grass in mine soils amended with humic acids.

    PubMed

    Vargas, Carmen; Pérez-Esteban, Javier; Escolástico, Consuelo; Masaguer, Alberto; Moliner, Ana

    2016-07-01

    Phytoremediation of contaminated mine soils requires the use of fast-growing, deep-rooted, high-biomass, and metal-tolerant plants with the application of soil amendments that promote metal uptake by plants. A pot experiment was performed to evaluate the combined use of vetiver grass (Chrysopogon zizanioides) and humic acid for phytoremediation of Cu and Zn in mine soils. Vetiver plants were grown in soil samples collected from two mine sites of Spain mixed with a commercial humic acid derived from leonardite at doses of 0, 2, 10, and 20 g kg(-1). Plant metal concentrations and biomass were measured and metal bioavailability in soils was determined by a low molecular weight organic acid extraction. Results showed that humic acid addition decreased organic acid-extractable metals in soil. Although this extraction method is used to estimate bioavailability of metals, it was not a good estimator under these conditions due to competition with the strong chelators in the added humic acid. High doses of humic acid also promoted root growth and increased Cu concentrations in plants due to formation of soluble metal-organic complexes, which enhanced removal of this metal from soil and its accumulation in roots. Although humic acid was not able to improve Zn uptake, it managed to reduce translocation of Zn and Cu to aerial parts of plants. Vetiver resulted unsuitable for phytoextraction, but our study showed that the combined use of this species with humic acid at 10-20 g kg(-1) could be an effective strategy for phytostabilization of mine soils.

  3. Cu retention in an acid soil amended with perlite winery waste.

    PubMed

    Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Calviño, David

    2016-02-01

    The effect of perlite waste from a winery on general soil characteristics and Cu adsorption was assessed. The studied soil was amended with different perlite waste concentrations corresponding to 10, 20, 40 and 80 Mg ha(-1). General soil characteristics and Cu adsorption and desorption curves were determined after different incubation times (from 1 day to 8 months). The addition of perlite waste to the soil increased the amounts of organic matter as well as soil nutrients such as phosphorus and potassium, and these increments were stable with time. An increase in Cu adsorption capacity was also detected in the perlite waste-amended soils. The effect of perlite waste addition to the soil had special relevance on its Cu adsorption capacity at low coverage concentrations and on the energy of the soil-Cu bonds.

  4. Weed seed inactivation in soil mesocosms via biosolarization with mature compost and tomato processing waste amendments.

    PubMed

    Achmon, Yigal; Fernández-Bayo, Jesús D; Hernandez, Katie; McCurry, Dlinka G; Harrold, Duff R; Su, Joey; Dahlquist-Willard, Ruth M; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

    2017-05-01

    Biosolarization is a fumigation alternative that combines passive solar heating with amendment-driven soil microbial activity to temporarily create antagonistic soil conditions, such as elevated temperature and acidity, that can inactivate weed seeds and other pest propagules. The aim of this study was to use a mesocosm-based field trial to assess soil heating, pH, volatile fatty acid accumulation and weed seed inactivation during biosolarization. Biosolarization for 8 days using 2% mature green waste compost and 2 or 5% tomato processing residues in the soil resulted in accumulation of volatile fatty acids in the soil, particularly acetic acid, and >95% inactivation of Brassica nigra and Solanum nigrum seeds. Inactivation kinetics data showed that near complete weed seed inactivation in soil was achieved within the first 5 days of biosolarization. This was significantly greater than the inactivation achieved in control soils that were solar heated without amendment or were amended but not solar heated. The composition and concentration of organic matter amendments in soil significantly affected volatile fatty acid accumulation at various soil depths during biosolarization. Combining solar heating with organic matter amendment resulted in accelerated weed seed inactivation compared with either approach alone. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  5. Carbon stabilization and microbial growth in acidic mine soils after addition of different amendments for soil reclamation

    NASA Astrophysics Data System (ADS)

    Zornoza, Raúl; Acosta, Jose; Ángeles Muñoz, María; Martínez-Martínez, Silvia; Faz, Ángel; Bååth, Erland

    2016-04-01

    The extreme soil conditions in metalliferous mine soils have a negative influence on soil biological activity and therefore on soil carbon estabilization. Therefore, amendments are used to increase organic carbon content and activate microbial communities. In order to elucidate some of the factors controlling soil organic carbon stabilization in reclaimed acidic mine soils and its interrelationship with microbial growth and community structure, we performed an incubation experiment with four amendments: pig slurry (PS), pig manure (PM) and biochar (BC), applied with and without marble waste (MW; CaCO3). Results showed that PM and BC (alone or together with MW) contributed to an important increment in recalcitrant organic C, C/N ratio and aggregate stability. Bacterial and fungal growths were highly dependent on pH and labile organic C. PS supported the highest microbial growth; applied alone it stimulated fungal growth, and applied with MW it stimulated bacterial growth. BC promoted the lowest microbial growth, especially for fungi, with no significant increase in fungal biomass. MW+BC increased bacterial growth up to values similar to PM and MW+PM, suggesting that part of the biochar was degraded, at least in short-term mainly by bacteria rather than fungi. PM, MW+PS and MW+PM supported the highest microbial biomass and a similar community structure, related with the presence of high organic C and high pH, with immobilization of metals and increased soil quality. BC contributed to improved soil structure, increased recalcitrant organic C, and decreased metal mobility, with low stimulation of microbial growth.

  6. Acid-base properties of humic substances from composted and thermally-dried sewage sludges and amended soils as determined by potentiometric titration and the NICA-Donnan model.

    PubMed

    Fernández, José M; Plaza, César; Senesi, Nicola; Polo, Alfredo

    2007-09-01

    The acid-base properties of humic acids (HAs) and fulvic acids (FAs) isolated from composted sewage sludge (CS), thermally-dried sewage sludge (TS), soils amended with either CS or TS at a rate of 80 t ha(-1)y(-1) for 3y and the corresponding unamended soil were investigated by use of potentiometric titrations. The non-ideal competitive adsorption (NICA)-Donnan model for a bimodal distribution of proton binding sites was fitted to titration data by use of a least-squares minimization method. The main fitting parameters of the NICA-Donnan model obtained for each HA and FA sample included site densities, median affinity constants and widths of affinity distributions for proton binding to low and high affinity sites, which were assumed to be, respectively, carboxylic- and phenolic-type groups. With respect to unamended soil HA and FA, the HAs and FAs from CS, and especially TS, were characterized by smaller acidic functional group contents, larger proton binding affinities of both carboxylic- and phenolic-type groups, and smaller heterogeneity of carboxylic and phenolic-type groups. Amendment with CS or TS led to a decrease of acidic functional group contents and a slight increase of proton binding affinities of carboxylic- and phenolic-type groups of soil HAs and FAs. These effects were more evident in the HA and FA fractions from CS-amended soil than in those from TS-amended soil.

  7. Carbon and nitrogen mineralization in vineyard acid soils amended with a bentonitic winery waste

    NASA Astrophysics Data System (ADS)

    Fernández-Calviño, David; Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Díaz-Raviña, Montserrat; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel

    2015-04-01

    Carbon mineralization and nitrogen ammonification processes were determined in different vineyard soils. The measurements were performed in samples non-amended and amended with different bentonitic winery waste concentrations. Carbon mineralization was measured as CO2 released by the soil under laboratory conditions, whereas NH4+ was determined after its extraction with KCl 2M. The time evolution of both, carbon mineralization and nitrogen ammonification, was followed during 42 days. The released CO2 was low in the analyzed vineyard soils, and hence the metabolic activity in these soils was low. The addition of the bentonitic winery waste to the studied soils increased highly the carbon mineralization (2-5 fold), showing that the organic matter added together the bentonitic waste to the soil have low stability. In both cases, amended and non-amended samples, the maximum carbon mineralization was measured during the first days (2-4 days), decreasing as the incubation time increased. The NH4+ results showed an important effect of bentonitic winery waste on the ammonification behavior in the studied soils. In the non-amended samples the ammonification was no detected in none of the soils, whereas in the amended soils important NH4+ concentrations were detected. In these cases, the ammonification was fast, reaching the maximum values of NH4 between 7 and 14 days after the bentonitic waste additions. Also, the percentages of ammonification respect to the total nitrogen in the soil were high, showing that the nitrogen provided by the bentonitic waste to the soil is non-stable. The fast carbon mineralization found in the soils amended with bentonitic winery wastes shows low possibilities of the use of this waste for the increasing the organic carbon pools in the soil.On the other hand, the use of this waste as N-fertilizer can be possible. However, due its fast ammonification, the waste should be added to the soils during active plant growth periods.

  8. Evolution of soil properties and metals in acid and alkaline mine tailing ponds after amendments and microorganisms application

    NASA Astrophysics Data System (ADS)

    Acosta, Jose A.; Faz, Ángel; Zornoza, Raúl; Martínez-Martínez, Silvia; Bech, Jaume

    2015-04-01

    Intense mining activities in the past were carried out in Cartagena-La Unión mining district, SE Spain, and caused excessive accumulation of toxic metals in tailing ponds which poses a high environmental and ecological risk. One of the remediation options gaining considerable interest in recent years is the in situ immobilization of metals. A corresponding reduction in the plant-available metal fraction allows re-vegetation and ecosystem restoration of the heavily contaminated sites. In addition, the use of microorganisms to improve the soil condition is a new tool used to increase spontaneous plant colonization. The aim of this research was to assess the effect of amendments (pig manure, sewage sludge, and lime) and microorganisms on the evolution of soil properties and metals in acid and alkaline tailing ponds and to evaluate the content of metals in Zygophylum fabago one year after amendments application. The study was carried out in two mine ponds (acid and alkaline). Twenty seven square field plots, each one consisting of 4 m2, were located in each pond. Four different doses of microorganism (EM) (0 ml, 20 ml, 100 ml and 200 ml of microorganism solution in each plot) and one dose of pig manure (5 kg per plot), sewage sludge (4 kg per plot) and lime (22 kg per plot) were used. Organic amendment doses were calculated according to European nitrogen legislations, and lime dose was calculated according with the potential acid production through total sulphur oxidation. Three replicates of each treatment (organic amendment + lime + microorganism dose 0, 1, 2, or 3) and control soil (with no amendments) were carried out. Plots were left to the semi-arid climate conditions after the addition of amendments to simulate real potential applications of the results. Soil samples was collected every 4 month from each plot during one year, after this time Zygophylum fabago plants were sampled from each plots. Soil properties including: pH, salinity, total, inorganic and

  9. Quality of trace element contaminated soils amended with compost under fast growing tree Paulownia fortunei plantation.

    PubMed

    Madejón, P; Xiong, J; Cabrera, F; Madejón, E

    2014-11-01

    The use of fast growing trees could be an alternative in trace element contaminated soils to stabilize these elements and improve soil quality. In this study we investigate the effect of Paulownia fortunei growth on trace element contaminated soils amended with two organic composts under semi-field conditions for a period of 18 months. The experiment was carried out in containers filled with tree different soils, two contaminated soils (neutral AZ and acid V) and a non contaminated soil, NC. Three treatments per soil were established: two organic amendments (alperujo compost, AC, and biosolid compost, BC) and a control without amendment addition. We study parameters related with fertility and contamination in soils and plants. Paulownia growth and amendments increased pH in acid soils whereas no effect of these factors was observed in neutral soils. The plant and the amendments also increased organic matter and consequently, soil fertility. Positive results were also found in soils that were only affected by plant growth (without amendment). A general improvement of "soil biochemical quality" was detected over time and treatments, confirming the positive effect of amendments plus paulownia. Even in contaminated soils, except for Cu and Zn, trace element concentrations in leaves were in the normal range for plants. Results of this mid-term study showed that Paulownia fortunei is a promising species for phytoremediation of trace element polluted soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Influence of Herbicide Triasulfuron on Soil Microbial Community in an Unamended Soil and a Soil Amended with Organic Residues

    PubMed Central

    Pose-Juan, Eva; Igual, José M.; Sánchez-Martín, María J.; Rodríguez-Cruz, M. S.

    2017-01-01

    The effect of organic amendments and pesticides on a soil microbial community has garnered considerable interest due to the involvement of microorganisms in numerous soil conservation and maintenance reactions. The aim of this work was to assess the influence on a soil microbial community of the simultaneous application of the herbicide triasulfuron at three doses (2, 10, and 50 mg kg-1), with an organic amendment [sewage sludge (SS) or green compost (GC)]. Dissipation kinetics, soil microbial biomass, dehydrogenase activity (DHA) and respiration, and the profile of phospholipid fatty acids (PLFAs) extracted from the soil, were determined in unamended (S) soil and amended (S+SS and S+GC) ones. Triasulfuron dissipation followed the single first-order kinetics model. Half-life (DT50) values were higher in the amended soils than in the unamended one for the 10 and 50 mg kg-1 doses. The dissipation rates were lower in the S+GC soil for the three herbicide doses applied. In general, soil biomass, DHA and respiration values increased in SS- and GC-amended soils compared to the unamended one. DHA values decreased (S and S+SS) or increased (S+GC) with the incubation time of soil with herbicide at the different doses applied. Respiration values increased with the herbicide doses applied and decreased with the incubation time, although maximum values were obtained for soils treated with the highest dose after 70 days of incubation. PLFA analysis indicated different effects of triasulfuron on the soil microbial community structure depending on the organic amendments. While the increasing triasulfuron doses resulted in deeper alterations in the S soil, the time after triasulfuron application was the most important variation in the S+SS and S+GC soils. The overall results indicate that the soil amendment has an effect on herbicide dissipation rate and the soil microbial community. Initially, a high dose of triasulfuron had detrimental effects on the soil microbial community

  11. Evaluation of ferrihydrite as amendment to restore an arsenic-polluted mine soil.

    PubMed

    Abad-Valle, P; Álvarez-Ayuso, E; Murciego, A

    2015-05-01

    The effectiveness of ferrihydrite as amendment to restore the soil habitat functioning of a soil polluted with As by mining activities was evaluated. Its influence on As mobility and phytoavailability was also assessed. Soil treated with increasing amendment doses (0, 1, 2, and 5 %) were analyzed for soil microbiological parameters such as basal soil respiration and dehydrogenase, β-glucosidase, urease, acid and alkaline phosphatase, and arylsulfatase activities. Batch leaching tests and plant growth experiments using ryegrass and alfalfa plants were performed. The treatment with ferrihydrite was effective to reduce As mobility and plant As uptake, translocation, and accumulation. Likewise, the soil microbiological status was generally improved as derived from basal soil respiration and dehydrogenase and acid and alkaline phosphatase activities, which showed increases up to 85, 45, 11, and 47 %, respectively, at a ferrihydrite addition rate of 5 %.

  12. Mitigation effects of silicon rich amendments on heavy metal accumulation in rice (Oryza sativa L.) planted on multi-metal contaminated acidic soil.

    PubMed

    Gu, Hai-Hong; Qiu, Hao; Tian, Tian; Zhan, Shu-Shun; Deng, Teng-Hao-Bo; Chaney, Rufus L; Wang, Shi-Zhong; Tang, Ye-Tao; Morel, Jean-Louis; Qiu, Rong-Liang

    2011-05-01

    The mechanisms of stabilization by silicon-rich amendments of cadmium, zinc, copper and lead in a multi-metal contaminated acidic soil and the mitigation of metal accumulation in rice were investigated in this study. The results from a pot experiment indicated that the application of fly ash (20 and 40gkg(-1)) and steel slag (3 and 6gkg(-1)) increased soil pH from 4.0 to 5.0-6.4, decreased the phytoavailability of heavy metals by at least 60%, and further suppressed metal uptake by rice. Diffusion gradient in thin-film measurement showed the heavy metal diffusion fluxes from soil to solution decreased by greater than 84% after remediation. X-ray diffraction analysis indicated the mobile metals were mainly deposited as their silicates, phosphates and hydroxides in amended treatments. Moreover, it was found metal translocation from stem to leaf was dramatically restrained by adding amendments, which might be due to the increase of silicon concentration and co-precipitation with heavy metals in stem. Finally, a field experiment showed the trace element concentrations in polished rice treated with amendments complied with the food safety standards of China. These results demonstrated fly ash and steel slag could be effective in mitigating heavy metal accumulation in rice grown on multi-metal contaminated acidic soils. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Green waste compost as an amendment during induced phytoextraction of mercury-contaminated soil.

    PubMed

    Smolinska, Beata

    2015-03-01

    Phytoextraction of mercury-contaminated soils is a new strategy that consists of using the higher plants to make the soil contaminant nontoxic. The main problem that occurs during the process is the low solubility and bioavailability of mercury in soil. Therefore, some soil amendments can be used to increase the efficiency of the Hg phytoextraction process. The aim of the investigation was to use the commercial compost from municipal green wastes to increase the efficiency of phytoextraction of mercury-contaminated soil by Lepidium sativum L. plants and determine the leaching of Hg after compost amendment. The result of the study showed that Hg can be accumulated by L. sativum L. The application of compost increased both the accumulation by whole plant and translocation of Hg to shoots. Compost did not affect the plant biomass and its biometric parameters. Application of compost to the soil decreased the leaching of mercury in both acidic and neutral solutions regardless of growing medium composition and time of analysis. Due to Hg accumulation and translocation as well as its potential leaching in acidic and neutral solution, compost can be recommended as a soil amendment during the phytoextraction of mercury-contaminated soil.

  14. Metal availability, soil nutrient, and enzyme activity in response to application of organic amendments in Cd-contaminated soil.

    PubMed

    Yang, Zhanbiao; Liu, Lixia; Lv, Yanfeng; Cheng, Zhang; Xu, Xiaoxun; Xian, Junren; Zhu, Xuemei; Yang, Yuanxiang

    2018-01-01

    The study investigated the effects of organic amendments: green tea amendment (GTA) and oil cake amendment (OCA) on Cd bioavailability, soil nutrients, and soil enzyme activity in Cd-contaminated soil. The amendments were added to the soil at the doses of 1, 3, and 5% and were incubated for 45 days. Then, pakchoi cabbage was planted to test the remediation effect of the above two organic amendments. The diethylenetriaminepentaacetic acid (DTPA)-extractable Cd in GTA and OCA treatments was reduced by 14.69-27.51 and 13.75-68.77%, respectively, compared to no amendment-applied treatment. The application of GTA and OCA notably decreased the proportion of exchangeable fraction of Cd, but increased the percentage of oxide and organic-bound fraction of Cd, thereby suppressing the uptake by pakchoi cabbage. Cd concentration of aboveground parts decreased by 8.21-18.05 and 7.77-35.89% in GTA and OCA treatments, respectively. Relative to the no amendment-applied treatment, both GTA and OCA had enhanced soil nutrients and enzyme activities largely. Redundancy analysis showed that organic matter, total P, available N, and DTPA-extractable Cd significantly affected the enzyme activities. Furthermore, the application of OCA at the dose of 5% was more effective in reducing bioavailable Cd, enhancing soil available nutrients and urease and catalase activities in contaminated soil. These results indicated that oil cake should be used to immobilize metal and improve fertility and quality of Cd-contaminated soil.

  15. Growth and elemental accumulation of plants grown in acidic soil amended with coal fly ash-sewage sludge co-compost

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wong, J.W.C.; Selvam, A.

    2009-10-15

    A greenhouse experiment was conducted to evaluate the growth and heavy-metal accumulation of Brassica chinensis and Agropyron elongatum in 10 and 25% ash-sludge co-compost (ASC)-amended loamy acidic soil (pH 4.51) at two different application rates: 20% and 40% (v/v). Soil pH increased, whereas electrical conductivity decreased with the amendment of ASC to soil. Bioavailable Cu, Zn, and Mn contents of ASC-amended soil decreased, whereas Ni, Pb, and B contents increased. Concentrations of bioavailable Cu, Zn, and Mn in sludge compost (SC)-amended soils were 5.57, 20.8, and 8.19 mg kg{sup -1}, respectively. These concentrations were significantly lower than those in soilmore » receiving an application rate of 20 or 25% ASC as 2.64, 8.48, and 5.26 mg kg(-1), respectively. Heavy metals and B contents of the composting mass significantly increased with an increase in ASC application rate from 20 to 40% (6.2 to 16.6 mg kg{sup -1} for 10% ASC- and 9.4 to 18.6 mg kg{sup -1} for 25% ASC-amended soil. However, when the ash content in co-compost increased from 10 to 25% during composting, bioavailable heavy-metal contents decreased. However, B contents increased with an increase in ash content. Addition of co-composts increased the dry-weight yield of the plants, and this increase was more obvious as the ash amendment rate in the co-composts and the ASC application rate increased. In case of B. chinensis, the biomass of 2.84 g/plant for 40% application of 25% ASC was significantly higher than SC (0.352 g/plant), which was 40% application of 10% ASC (0.434 g/plant) treatments. However, in A. elongatum, the differences between biomass of plants grown with 10% (1.34-1.94 g/ plant) and 25% ASC (2.12-2.21 g/plant) were not significantly different. ASC was favorable in increasing the growth of B. chinensis and A. elongatum. The optimal ash amendment to the sludge composting and ASC application rates were at 25 and 20%, respectively.« less

  16. Effects of soil amendment on soil characteristics and maize yield in Horqin Sandy Land

    NASA Astrophysics Data System (ADS)

    Zhou, L.; Liu, J. H.; Zhao, B. P.; Xue, A.; Hao, G. C.

    2016-08-01

    A 4-year experiment was conducted to investigate the inter-annual effects of sandy soil amendment on maize yield, soil water storage and soil enzymatic activities in sandy soil in Northeast China in 2010 to 2014. We applied the sandy soil amendment in different year, and investigated the different effects of sandy soil amendment in 2014. There were six treatments including: (1) no sandy soil amendment application (CK); (2) one year after applying sandy soil amendment (T1); (3) two years after applying sandy soil amendment(T2); (4) three years after applying sandy soil amendment(T3); (5)four years after applying sandy soil amendment(T4); (6) five years after applying sandy soil amendment (T5). T refers to treatment, and the number refers to the year after application of the sandy soil amendment. Comparing with CK, sandy soil amendments improved the soil water storage, soil urease, invertase, and catalase activity in different growth stages and soil layers, the order of soil water storage in all treatments roughly performed: T3 > T5 > T4 > T2 > T1 > CK. the order of soil urease, invertase, and catalase activity in all treatments roughly performed: T5 > T3 > T4 > T2 > T1 > CK. Soil application of sandy soil amendment significantly (p≤⃒0.05) increased the grain yield and biomass yield by 22.75%-41.42% and 29.92%-45.45% respectively, and maize yield gradually increased with the years go by in the following five years. Sandy soil amendment used in poor sandy soil had a positive effect on soil water storage, soil enzymatic activities and maize yield, after five years applied sandy soil amendment (T5) showed the best effects among all the treatments, and deserves further research.

  17. Modification of chemical properties, Cu fractionation and enzymatic activities in an acid vineyard soil amended with winery wastes: A field study.

    PubMed

    Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía; Díaz-Raviña, Montserrat; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Calviño, David

    2017-11-01

    The effects of adding two winery wastes, perlite waste (PW) and bentonite waste (BW), to an acid vineyard soil were assessed using some chemical and biological soil properties in a field study that lasted 18 months. The addition of PW (up to 81 Mg ha -1 ) had neither significant nor permanent effects on soil characteristics such as the pH, organic matter content or nutrient concentrations, the amounts of copper or zinc, or the electrical conductivity. Moreover, no persistent negative effects were found on the enzymatic activities after PW application. In contrast, soil that was amended with up to 71 Mg BW ha -1 showed increases in its soil pH values, exchangeable potassium and water soluble potassium and phosphorus contents. In addition, it caused significant increases in the electrical conductivity and water-soluble Cu. In addition, the phosphomonoesterase enzymatic activity decreased significantly (up to 28%) in response to the amendment with 71 Mg BW ha -1 . These results showed that adding BW and PW to the soil may be a good agronomic practice for recycling these types of wastes. However, in the case of PW, its use as a soil amendment must be performed with caution to control its possible harmful effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Obrycki, John F.; Scheckel, Kirk G.; Basta, Nicholas T.

    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 phosphate (TSP) at 5:1 P:Pb molar ratios. Soil was acidified, neturalized and re-acidified to encourage Pb phosphate formation. PRSTM-probes were used to evaluate changes in soil solution chemistry. Soil acidification did not decrease in vitro bioaccessible (IVBA) Pb using either a pH 1.5, 0.4 M glycine solution or a pH 2.5 solution with organicmore » acids. PRSTM-probe data found soluble Pb increased 10-fold in acidic conditions compared to circumnetural pH conditions. In acidic conditions (p = 3-4), TSP treated soils increased detected P 10-fold over untreated soils. Bone meal application did not increase PRSTM-probe detected P, indicating there may have been insufficient P to react with Pb. X-ray absorption spectroscopy suggested a 10% increase in pyromorphite formation for the TSP treated soil only. Treatments increased soil electrical conductivity above 16 mS cm -1, potentially causing a new salinity hazard. This study used a novel approach by combining the human ingestion endpoint, PRSTM-probes, and X-ray absorption spectroscopy to evaluate treatment efficacy. PRSTM-probe data indicated potentially excess Ca relative to P across incubation steps that could have competed with Pb for soluble P. More research is needed to characterize soil solutions in Pb contaminated urban soils to identify where P treatments might be effective and when competing cations, such as Ca, Fe, and Zn may limit low rate P applications for treating Pb soils.« less

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

    PubMed

    Obrycki, John F; Scheckel, Kirk G; Basta, Nicholas T

    2017-01-01

    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 phosphate (TSP) at 5:1 P:Pb molar ratios. Soil was acidified, neturalized and re-acidified to encourage Pb phosphate formation. PRSTM-probes were used to evaluate changes in soil solution chemistry. Soil acidification did not decrease in vitro bioaccessible (IVBA) Pb using either a pH 1.5, 0.4 M glycine solution or a pH 2.5 solution with organic acids. PRSTM-probe data found soluble Pb increased 10-fold in acidic conditions compared to circumnetural pH conditions. In acidic conditions (p = 3-4), TSP treated soils increased detected P 10-fold over untreated soils. Bone meal application did not increase PRSTM-probe detected P, indicating there may have been insufficient P to react with Pb. X-ray absorption spectroscopy suggested a 10% increase in pyromorphite formation for the TSP treated soil only. Treatments increased soil electrical conductivity above 16 mS cm -1 , potentially causing a new salinity hazard. This study used a novel approach by combining the human ingestion endpoint, PRSTM-probes, and X-ray absorption spectroscopy to evaluate treatment efficacy. PRSTM-probe data indicated potentially excess Ca relative to P across incubation steps that could have competed with Pb for soluble P. More research is needed to characterize soil solutions in Pb contaminated urban soils to identify where P treatments might be effective and when competing cations, such as Ca, Fe, and Zn may limit low rate P applications for treating Pb soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Carbon mineralization in acidic, xeric forest soils: induction of new activities.

    PubMed

    Tate, R L

    1985-08-01

    Carbon mineralization was examined in Lakehurst and Atsion sands collected from the New Jersey Pinelands and in Pahokee muck from the Everglades Agricultural Area. Objectives were (i) to estimate the carbon mineralization capacities of acidic, xeric Pinelands soils in the absence of exogenously supplied carbon substrate (nonamended carbon mineralization rate) and to compare these activities with those of agriculturally developed pahokee muck, and (ii) to measure the capacity for increased carbon mineralization in the soils after carbon amendment. In most cases, nonamended carbon mineralization rates were greater in samples of the acid- and moisture-stressed Pinelands soils than in Pahokee muck collected from a fallow (bare) field. Carbon amendment resulted in augmented catabolic activity in Pahokee muck samples, suggesting that the microbial community was carbon limited in this soil. With many of the substrates, no stimulation of the catabolic rate was detected after amendment of Pinelands soils. This was documented by the observation that amendment of Pahokee muck with an amino acid mixture, glucose, or acetate resulted in a 3.0-, 3.9-, or 10.5-fold stimulation of catabolic activity, respectively, for the added substrate. In contrast, amendment of the Pinelands soils resulted in increased amino acid and acetate catabolic rates in Lakehurst sand and increased acetate metabolism only in Atsion sand. Other activities were unchanged. The increased glucose respiration rates resulted from stimulation of existing microbial activity rather than from microbial proliferation since no change in the microbial growth rate, as estimated by the rate of incorporation of C-labeled acetate into cell membranes, occurred after glucose amendment of the soils. A stimulation of microbial growth rate was recorded with glucose-amended Lakehurst sand collected from the B horizon.

  1. Reutilization of granite powder as an amendment and fertilizer for acid soils.

    PubMed

    Barral Silva, M T; Silva Hermo, B; García-Rodeja, E; Vázquez Freire, N

    2005-11-01

    The properties of granite powders--a granite manufacturing waste product-were analyzed to assess their potential use as amendments and fertilizers on acid soils. Two types of powders were characterized: one produced during cutting of granite with a diamond-edged disc saw, comprising only rock powder, the other produced during cutting with a multi-blade bandsaw, containing calcium hydroxide and metal filings added during the cutting procedure. The acid neutralizing capacity of the granite powders was assessed in short- (2-3 h) and medium-term (1-30 d) experiments. The powders showed a buffering capacity at around pH 8, which corresponded to the rapid dissolution of basic cations, and another buffering effect at pH<4.5, attributable to the dissolution of Fe and Al. The acid neutralizing capacity (ANC) determined in the short-term experiments, to a final pH of 4.5, varied between 5 and 61 cmol H+kg(-1) powder. The ANC to pH 4.5 obtained in the medium-term experiments was much higher than that obtained in the short-term experiments, reaching a maximum ANC value of 200 cmol H+kg(-1) powder. There was no great difference in the neutralizing capacity determined at between 1 and 30 d. The most abundant elements in acid solutions obtained at the end of medium-term experiments were Mg and Ca for disc saw powders, whereas Ca and Fe (at pH<5) were the most soluble elements in the bandsaw powders. The rapid release of these cations suggests the possible effective use of the granite powders as a source of nutrients on being added to acid soils.

  2. Enzymatic activities in a semiarid soil amended with different soil treatment: Soil quality improvement

    NASA Astrophysics Data System (ADS)

    Hueso González, Paloma; Elbl, Jakub; Dvořáčková, Helena; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

    2017-04-01

    The use of soil quality indicators may be an effective approach to assess the positive effect of the organic amendment as good restoration methods. Relying on the natural fertility of the soil, the most commonly chemical and physical parameters used to evaluate soil quality are depend to the soil biological parameters. The measurement of soil basal respiration and the mineralization of organic matter are commonly accepted as a key indicator for measuring changes to soil quality. Thus, the simultaneous measurement of various enzymes seems to be useful to evaluate soil biochemical activity and related processes. In this line, Dehydrogenase activity is widely used in evaluating the metabolic activity of soil microorganisms and to evaluate the effects caused by the addition of organic amendments. Variations in phosphatase activity, apart from indicating changes in the quantity and quality of soil phosphorated substrates, are also good indicators of soil biological status. This study assesses the effect of five soil amendments as restoration techniques for semiarid Mediterrenean ecosystems. The goal is to interpret the status of biological and chemical parameters in each treatment as soil quality indicators in degraded forests. The main objectives were to: i) analyze the effect of various organic amendments on the enzimatic activity of soil; ii) analyze the effect of the amendments on soil respiration; iii) assess the effect of these parameters on the soil chemical properties which are indicative of soil healthy; and iv) evaluated form the land management point of view which amendment could result a effective method to restore Mediterranean degraded areas. An experimental paired-plot layout was established in southern of Spain (homogeneous slope gradient: 7.5%; aspect: N170). Five amendments were applied in an experimental set of plots: straw mulching; mulch with chipped branches of Aleppo Pine (Pinus halepensis Mill.); TerraCotten hydroabsobent polymers; sewage

  3. Effects of the addition and aging of humic acid-based amendments on the solubility of Cd in soil solution and its accumulation in rice.

    PubMed

    Yu, Yao; Wan, Yanan; Camara, Aboubacar Younoussa; Li, Huafen

    2018-04-01

    Humic substances can reduce mobility and bio-accessibility of Cd in soil and therefore inhibit its uptake by rice, which is a major source of human Cd intake. Yet, the effects of aging humic substances are not fully understood. A rice pot experiment was conducted to evaluate the effects of humic acid-based amendments on the mobility of Cd in soil solution and its uptake by rice when amendments were freshly added or aged for 130 d. The results showed that the aged and the unaged amendments generally decreased Cd concentration in soil solution, but the effect declined with time. Unaged HA-K (humic-potassium) reduced Cd concentration by 88% for the first sampling, but this dropped to 46% for the last sampling, compared to that of the control. All amendments, whether aged or not, reduced the content of Cd in rice seedlings, as well as in mature plants. Aged and unaged woody peat reduced the Cd content in seedlings by 79% and in grains by 70%, respectively. Aging of amendments caused lower pH and higher Cd concentration in the soil solution for all amendments and accordingly, the Cd content in rice seedlings or each part of mature plants in the aged group was higher than that of the unaged group. The applied amendments might reduce the solubility of Cd through the alteration in soil pH, and thus inhibit the uptake of Cd by rice, but the effects diminished with aging. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Cadmium Sorption Characteristics of Soil Amendments and its Relationship with the Cadmium Uptake by Hyperaccumulator and Normal Plants in Amended Soils

    PubMed Central

    Sun, Yan; Wu, Qi-Tang; Lee, Charles C.C.; Li, Baoqin; Long, Xinxian

    2013-01-01

    In order to select appropriate amendments for cropping hyperaccumulator or normal plants on contaminated soils and establish the relationship between Cd sorption characteristics of soil amendments and their capacity to reduce Cd uptake by plants, batch sorption experiments with 11 different clay minerals and organic materials and a pot experiment with the same amendments were carried out. The pot experiment was conducted with Sedum alfredii and maize (Zea mays) in a co-cropping system. The results showed that the highest sorption amount was by montmorillonite at 40.82 mg/g, while mica was the lowest at only 1.83 mg/g. There was a significant negative correlation between the n value of Freundlich equation and Cd uptake by plants, and between the logarithm of the stability constant K of the Langmuir equation and plant uptake. Humic acids (HAs) and mushroom manure increased Cd uptake by S. alfredii, but not maize, thus they are suitable as soil amendments for the co-cropping S. alfredii and maize. The stability constant K in these cases was 0.14–0.16 L/mg and n values were 1.51–2.19. The alkaline zeolite and mica had the best fixation abilities and significantly decreased Cd uptake by the both plants, with K ≥ 1.49 L/mg and n ≥ 3.59. PMID:24912231

  5. Humic Substances in Organic Wastes and their Effects on Amended Soils

    NASA Astrophysics Data System (ADS)

    Senesi, N.; Ciavatta, C.; Plaza, C.

    2009-04-01

    Soil humic substances (HS) are universally recognized to play a major role in a wide number of agronomic and environmental processes. For example, soil HS are able to bind mineral particles together, thus promoting a good soil structure, constitute an important source of nutrients for plants and microorganisms, contribute largely to the acid-base buffering capacity of soils, and exert a marked control on the biological availability, physico-chemical behavior, and environmental fate of toxic metal ions and xenobiotics. For these reasons, the knowledge of the short- and long-term effects of organic amendments on the status, quality, and reactivity of indigenous soil HS is of paramount importance. The objective of this presentation is to provide an overview of the chemical and physico-chemical data available in the literature for the evaluation of the effects of organic wastes of various origin and nature used as soil amendments on the composition, structure, and chemical reactivity of native soil HS. In general, HS-like components of organic wastes are typically characterized by a relatively larger presence of aliphatic, amide, and polysaccharide structures, simple structural components of wide molecular heterogeneity, smaller contents of oxygen, acidic functional groups, and organic free radicals, and smaller degrees of aromatic ring polycondensation, polymerization, and humification than native soil HS. Further, with respect to native soil HS, HS-like fractions from organic wastes generally exhibit smaller binding capacities and affinities for metal ions and organic xenobiotics. Appropriate treatment processes of raw organic wastes able to produce environmentally safe and agronomically efficient soil amendments, such as composting, yield HS-like fractions characterized by chemical and physico-chemical features that approach those of native soil HS. In general, aliphatic, polysaccharide, and lignin structures and S- and N-containing groups of the HS-like fractions

  6. AMENDING SOILS WITH PHOSPHATE AS MEANS TO ...

    EPA Pesticide Factsheets

    Ingested soil and surface dust may be important contributors to elevated blood lead (Pb) levels in children exposed to Pb contaminated environments. Mitigation strategies have typically focused on excavation and removal of the contaminated soil. However, this is not always feasible for addressing widely disseminated contamination in populated areas often encountered in urban environments. The rationale for amending soils with phosphate is that phosphate will promote formation of highly insoluble Pb species (e.g., pyromorphite minerals) in soil, which will remain insoluble after ingestion and, therefore, inaccessible to absorption mechanisms in the gastrointestinal tract (GIT). Amending soil with phosphate might potentially be used in combination with other methods that reduce contact with or migration of contaminated soils, such as covering the soil with a green cap such as sod, clean soil with mulch, raised garden beds, or gravel. These remediation strategies may be less expensive and far less disruptive than excavation and removal of soil. This review evaluates evidence for efficacy of phosphate amendments for decreasing soil Pb bioavailability. Evidence is reviewed for (1) physical and chemical interactions of Pb and phosphate that would be expected to influence bioavailability, (2) effects of phosphate amendments on soil Pb bioaccessibility (i.e., predicted solubility of Pb in the GIT), and (3) results of bioavailability bioassays of amended soils con

  7. Carbon Mineralization in Acidic, Xeric Forest Soils: Induction of New Activities †

    PubMed Central

    Tate, Robert L.

    1985-01-01

    Carbon mineralization was examined in Lakehurst and Atsion sands collected from the New Jersey Pinelands and in Pahokee muck from the Everglades Agricultural Area. Objectives were (i) to estimate the carbon mineralization capacities of acidic, xeric Pinelands soils in the absence of exogenously supplied carbon substrate (nonamended carbon mineralization rate) and to compare these activities with those of agriculturally developed pahokee muck, and (ii) to measure the capacity for increased carbon mineralization in the soils after carbon amendment. In most cases, nonamended carbon mineralization rates were greater in samples of the acid- and moisture-stressed Pinelands soils than in Pahokee muck collected from a fallow (bare) field. Carbon amendment resulted in augmented catabolic activity in Pahokee muck samples, suggesting that the microbial community was carbon limited in this soil. With many of the substrates, no stimulation of the catabolic rate was detected after amendment of Pinelands soils. This was documented by the observation that amendment of Pahokee muck with an amino acid mixture, glucose, or acetate resulted in a 3.0-, 3.9-, or 10.5-fold stimulation of catabolic activity, respectively, for the added substrate. In contrast, amendment of the Pinelands soils resulted in increased amino acid and acetate catabolic rates in Lakehurst sand and increased acetate metabolism only in Atsion sand. Other activities were unchanged. The increased glucose respiration rates resulted from stimulation of existing microbial activity rather than from microbial proliferation since no change in the microbial growth rate, as estimated by the rate of incorporation of 14C-labeled acetate into cell membranes, occurred after glucose amendment of the soils. A stimulation of microbial growth rate was recorded with glucose-amended Lakehurst sand collected from the B horizon. PMID:16346862

  8. Biochar amendment immobilizes lead in rice paddy soils and reduces its phytoavailability

    PubMed Central

    Li, Honghong; Liu, Yuting; Chen, Yanhui; Wang, Shanli; Wang, Mingkuang; Xie, Tuanhui; Wang, Guo

    2016-01-01

    This study aimed to determine effects of rice straw biochar on Pb sequestration in a soil-rice system. Pot experiments were conducted with rice plants in Pb-contaminated paddy soils that had been amended with 0, 2.5, and 5% (w/w) biochar. Compared to the control treatment, amendment with 5% biochar resulted in 54 and 94% decreases in the acid soluble and CaCl2-extractable Pb, respectively, in soils containing rice plants at the maturity stage. The amount of Fe-plaque on root surfaces and the Pb concentrations of the Fe-plaque were also reduced in biochar amended soils. Furthermore, lead species in rice roots were determined using Pb L3-edge X-ray absorption near edge structure (XANES), and although Pb-ferrihydrite complexes dominated Pb inventories, increasing amounts of organic complexes like Pb-pectins and Pb-cysteine were found in roots from the 5% biochar treatments. Such organic complexes might impede Pb translocation from root to shoot and subsequently reduce Pb accumulation in rice with biochar amendment. PMID:27530495

  9. Biochar amendment immobilizes lead in rice paddy soils and reduces its phytoavailability

    NASA Astrophysics Data System (ADS)

    Li, Honghong; Liu, Yuting; Chen, Yanhui; Wang, Shanli; Wang, Mingkuang; Xie, Tuanhui; Wang, Guo

    2016-08-01

    This study aimed to determine effects of rice straw biochar on Pb sequestration in a soil-rice system. Pot experiments were conducted with rice plants in Pb-contaminated paddy soils that had been amended with 0, 2.5, and 5% (w/w) biochar. Compared to the control treatment, amendment with 5% biochar resulted in 54 and 94% decreases in the acid soluble and CaCl2-extractable Pb, respectively, in soils containing rice plants at the maturity stage. The amount of Fe-plaque on root surfaces and the Pb concentrations of the Fe-plaque were also reduced in biochar amended soils. Furthermore, lead species in rice roots were determined using Pb L3-edge X-ray absorption near edge structure (XANES), and although Pb-ferrihydrite complexes dominated Pb inventories, increasing amounts of organic complexes like Pb-pectins and Pb-cysteine were found in roots from the 5% biochar treatments. Such organic complexes might impede Pb translocation from root to shoot and subsequently reduce Pb accumulation in rice with biochar amendment.

  10. Amending metal contaminated mine soil with biochars to sequester metals and improve plant growth cover

    EPA Science Inventory

    There are numerous mine spoil sites in the U.S. Pacific Northwest that contain highly acidic, heavy metal-laden soils, which limits establishment of a soil-stabilizing plant cover. Biochars may be a suitable soil amendment to reduce toxic metals, improve soil fertility, soil wa...

  11. Effects of sewage sludge amendment on the properties of two Brazilian oxisols and their humic acids.

    PubMed

    Bertoncini, E I; D'Orazio, V; Senesi, N; Mattiazzo, M E

    2008-07-01

    The effect of sewage sludge (SS) amendment on the general properties of the top layers of a sandy and a clayey oxisols and on the nature of their humic acid (HA) fractions was evaluated by chemical and physico-chemical techniques. The amended soils, especially the sandy soil, benefited of SS amendment by increasing their pH to above neutrality and enhancing the contents of C, N, P, and Ca and cation exchange capacity. The SS-HA-like sample showed larger H and N contents and a greater aliphatic character and humification degree than the HAs isolated from non-amended soils. The composition and structure of amended soil HAs were affected by SS application as a function of soil type and layer. In particular, N-containing groups and aliphatic structures of SS-HA-like sample appears to be partially incorporated in the amended soil HAs, and these effects were more evident in the HAs from the sandy oxisol.

  12. Mineral materials as feasible amendments to stabilize heavy metals in polluted urban soils.

    PubMed

    Zhang, Mingkui; Pu, Jincheng

    2011-01-01

    Four minerals, agricultural limestone (AL), rock phosphate (RP), palygorskite (PG), and calcium magnesium phosphate (CMP), were evaluated by means of chemical fractions of heavy metals in soils and concentrations of heavy metals in leachates from columns to determine their ability to stabilize heavy metals in polluted urban soils. Two urban soils (calcareous soil and acidic soil) polluted with cadmium, copper, zinc and lead were selected and amended in the laboratory with the mineral materials) for 12 months. Results indicated that application of the mineral materials reduced exchangeable metals in the sequence of Pb, Cd > Cu > Zn. The reduction of exchangeable fraction of heavy metals in the soils amended with different mineral materials followed the sequence of CMP, PG > AL > RP. Reductions of heavy metals leached were based on comparison with cumulative totals of heavy metals eluted through 12 pore volumes from an untreated soil. The reductions of the metals eluted from the calcareous soil amended with the RP, AL, PG and CMP were 1.98%, 38.89%, 64.81% and 75.93% for Cd, 8.51%, 40.42%, 60.64% and 55.32% for Cu, 1.76%, 52.94%, 70.00% and 74.12% for Pb, and 28.42%, 52.74%, 64.38% and 49.66% for Zn. Those from the acidic soil amended with the CMP, PG, AL, and RP were 25.65%, 68.06%, 78.01% and 79.06% for Cd, 26.56%, 49.64%, 43.40% and 34.68% for Cu, 44.44%, 33.32%, 61.11% and 69.44% for Pb, and 18.46%, 43.77%, 41.98% and 40.68% for Zn. The CMP and PG treatments were superior to the AL and RP for stabilizing heavy metals in the polluted urban soils.

  13. Effects of poultry manure on soil biochemical properties in phthalic acid esters contaminated soil.

    PubMed

    Gao, Jun; Qin, Xiaojian; Ren, Xuqin; Zhou, Haifeng

    2015-12-01

    This study aimed to evaluate the effects of poultry manure (PM) on soil biological properties in DBP- and DEHP-contaminated soils. An indoor incubation experiment was conducted. Soil microbial biomass C (Cmic), soil enzymatic activities, and microbial phospholipid fatty acid (PLFA) concentrations were measured during incubation period. The results indicated that except alkaline phosphatase activity, DBP and DEHP had negative effects on Cmic, dehydrogenase, urease, protease activities, and contents of total PLFA. However, 5 % PM treatment alleviated the negative effects of PAEs on the above biochemical parameters. In DBP-contaminated soil, 5 % PM amendment even resulted in dehydroenase activity and Cmic content increasing by 17.8 and 11.8 % on the day 15 of incubation, respectively. During the incubation periods, the total PLFA contents decreased maximumly by 17.2 and 11.6 % in DBP- and DEHP-contaminated soils without PM amendments, respectively. Compared with those in uncontaminated soil, the total PLFA contents increased slightly and the value of bacPLFA/fugalPLFA increased significantly in PAE-contaminated soils with 5 % PM amendment. Nevertheless, in both contaminated soils, the effects of 5 % PM amendment on the biochemical parameters were not observed with 10 % PM amendment. In 10 % PM-amended soils, DBP and DEHP had little effect on Cmic, soil enzymatic activities, and microbial community composition. At the end of incubation, the effects of PAEs on these parameters disappeared, irrespective of PM amendment. The application of PM ameliorated the negative effect of PAEs on soil biological environment. However, further work is needed to study the effect of PM on soil microbial gene expression in order to explain the change mechanisms of soil biological properties.

  14. The EDTA Amendment in Phytoextraction of (134)Cs From Soil by Indian Mustard (Brassica juncea).

    PubMed

    Tjahaja, Poppy Intan; Sukmabuana, Putu; Roosmini, Dwina

    2015-01-01

    Soil contamination with radiocaesium is a significant problem at any countries when a nuclear accident occurred. Recently, phytoextraction technique is developed to remediate the contaminated environment. However, the application is limited by the availability of the contaminant for root uptake. Therefore, a green house trial experiment of soil amendment with ethylene diamine tetraacetic acid (EDTA) has been conducted to examine (134)Cs availability for root uptake. Two groups of Indian mustard (Brassica juncea) were cultivated in (134)Cs contaminated soil. The soil in the first group was treated with EDTA amendment, while the other was not. Plant growth was observed gravimetrically and the (134)Cs concentration in soil as well as plants were determined using gamma spectrometry. The plant uptake capacity was determined as transfer factor (Fv), and the Fv values of 0.22 ± 0.0786 and 0.12 ± 0.039 were obtained for the soil treated with and without EDTA amendment, respectively. The phytoextraction efficiency of the plant cultivated in (134)Cs contaminated soil both with and without EDTA amendment was low. The EDTA amendment to the soil seems to enhance the (134)Cs availability for root uptake of Indian mustard and can still be considered to assist the field phytoremediation of contaminated soil.

  15. Immobilization of soil cadmium using combined amendments of illite/smectite clay with bone chars.

    PubMed

    Li, Hong; Ou, Jieyong; Wang, Xuedong; Yan, Zengguang; Zhou, Youya

    2018-05-12

    The widespread use of cadmium (Cd)-containing organic fertilizers is a source of heavy metal inputs to agricultural soils in suburban areas. Therefore, the research and development of new materials and technologies for the remediation of Cd-contaminated soil is of great significance and has the potential to guarantee the safety of agricultural products and the protection of human health. We performed pot experiments to determine the potential of combined amendments of illite/smectite (I/S) clay with bone chars for the remediation of Cd-contaminated agricultural soils in a suburban area of Beijing, China. The results showed that both diethylene triamine pentaacetic acid (DTPA)-extractable Cd in soil and the Cd in Brassica chinensis were significantly decreased by the application of 1, 2, or 5% combined amendments with various I/S and bone char (BC) ratios. The higher proportions of BC used in the combined amendments resulted in a better immobilization of soil Cd. The application of the 5% amendment that combined I/S with either pig or cattle BC resulted in the best immobilization. All of the combined amendments, regardless of the composition and ratio of the components, had no negative effects on the growth of B. chinensis. Therefore, it was concluded that combined amendments of I/S and BC have a good potential for remediating Cd-contaminated soils.

  16. Application of microwave-pretreated cephalosporin mycelial dreg (CMD) as soil amendment: Temporal changes in chemical and fluorescent parameters of soil organic matter.

    PubMed

    Cai, Chen; Liu, Huiling

    2018-04-15

    Land application of treated cephalosporin mycelial dreg (CMD) as a soil amendment is an alternative to its disposal in landfills and incineration because it has environmental and agronomic benefits. This study validated the efficacy of using the dewatered, microwave-pretreated CMD as a soil amendment. Pot experiments were conducted to assess the temporal changes in soil organic matter (SOM) profiles via chemical and fluorescent parameters. During the ageing period, the CMD-treated soil experienced a sudden rise in soil pH and soil electrical conductivity, along with a rapid decline in soil organic carbon and soil organic nitrogen content. The specific Ex/Em peak related to protein-like substances gradually disappeared, while those related to humic acid-like substances continued to increase thereafter. Fluorescence regional integration (FRI) results showed an ascended P V,n /P III,n index (1.94) and significant correlations with chemical data (M 2 =0.2875, r=0.8441, P<0.001, 999 permutations for Procrustes analysis). Taken together, despite the temporal changes in chemical and fluorescent data after soil conditioning, the increased content of SOM containing humic acid-like substances was observed at the end of the incubation period compared with control soil samples, indicating that the microwave-pretreated CMD might be applied as a soil amendment. Copyright © 2017. Published by Elsevier B.V.

  17. Mitigation effects of silicon rich amendments on heavy metal accumulation in rice (Oryza sativa L.) planted on multi-metal contaminated acidic soil

    USDA-ARS?s Scientific Manuscript database

    The mechanisms of stabilization by silicon-rich amendments of cadmium, zinc, copper and lead in a multi-metal contaminated acidic soil and the mitigation of metal accumulation in rice were investigated in this study. The results from a pot experiment indicated that the application of fly ash (20 and...

  18. Changes in soil properties and in the growth of Lolium multiflorum in an acid soil amended with a solid waste from wineries.

    PubMed

    Nóvoa-Muñoz, J C; Simal-Gándara, J; Fernández-Calviño, D; López-Periago, E; Arias-Estévez, M

    2008-10-01

    The agronomic utility of a solid waste, waste perlite (WP), from wine companies was assessed. In this sense, the natural characteristics of the waste were measured, followed by the monitoring of its effects on the chemical properties of acid soils and the growth of Lolium multiflorum. Taking into account that heavy metals associated to the waste (such as Cu, Zn and Mn) could cause problems when used as amendment, the changes in their total levels and in their soil fractionation were also studied, together with their total contents in L. multiflorum. The high content in C (214gkg(-1)), N (25gkg(-1)), P (534mgkg(-1)) and K (106gkg(-1)) of WP turned it into an appropriate amendment to increase soil fertility, solving at the same time its disposal. WP contributed to increase soil pH (in 2 pH units) and cation exchange capacity (CEC increased in 3cmolckg(-1)units), but reduced the potential Cu phytotoxicity due to a change in Cu distribution towards less soluble fractions. The growth of L. multiflorum adequately responds to the treatment with WP at addition rates below 2.5gkg(-1), whereas the imbalance between nutrients can justify the reduction in biomass production at higher WP addition rates. The levels of heavy metals analyzed in L. multiflorum biomass (8-85gkg(-1)) do not seem to cause undesirable effects on its growth.

  19. Functional Diversity of Microbial Communities in Sludge-Amended Soils

    NASA Astrophysics Data System (ADS)

    Sun, Y. H.; Yang, Z. H.; Zhao, J. J.; Li, Q.

    The BIOLOG method was applied to exploration of functional diversity of soil microbial communities in sludge-amended soils sampled from the Yangtze River Delta. Results indicated that metabolic profile, functional diversity indexes and Kinetic parameters of the soil microbial communities changed following soil amendment with sewage sludge, suggesting that the changes occurred in population of the microbes capable of exploiting carbon substrates and in this capability as well. The kinetic study of the functional diversity revealed that the metabolic profile of the soil microbial communities exhibited non-linear correlation with the incubation time, showing a curse of sigmoid that fits the dynamic model of growth of the soil microbial communities. In all the treatments, except for treatments of coastal fluvo-aquic soil amended with fresh sludge and dried sludge from Hangzhou, kinetic parameters K and r of the functional diversity of the soil microbial communities decreased significantly and parameter S increased. Changes in characteristics of the functional diversity well reflected differences in C utilizing capacity and model of the soil microbial communities in the sludge-amended soils, and changes in functional diversity of the soil microbial communities in a particular eco-environment, like soil amended with sewage sludge.

  20. ADSORPTION OF CADMIUM ON BIOSOLIDS-AMENDED SOILS

    EPA Science Inventory

    A considerable controversy exists over the biosolid phase (organic or inorganic) responsible for the reduction in phytoavailable Cd in soils amended with biosolids as compared to soils amended with inorganic salts. To test the importance of these two phases, 2 biosolids, 15 bioso...

  1. Assessment of the use potential of edible sea urchins (Paracentrotus lividus) processing waste within the agricultural system: influence on soil chemical and biological properties and bean (Phaseolus vulgaris) and wheat (Triticum vulgare) growth in an amended acidic soil.

    PubMed

    Garau, Giovanni; Castaldi, Paola; Deiana, Salvatore; Campus, Paolo; Mazza, Antonio; Deiana, Pietrino; Pais, Antonio

    2012-10-30

    In this study we evaluated the influence of ground purple sea urchin (Paracentrotus lividus) endoskeletons, a processing waste common to all edible sea urchin plants, on the chemical, biochemical and microbiological features of an acidic (pH 5.65) sandy-loam soil. The purple sea urchin endoskeletons were characterized by a high content of total carbonates (∼94%), a moderately alkaline pH in water (pH 7.88) and electrical conductivity values (3.55 mS/cm) very similar to those of commercial lime. To evaluate the influence of the P. lividus endoskeletons on soil properties four different amendment rates were tested, notably 0.5, 1.0, 3.0 and 5.0% based on soil dry weight, and the effects compared with those recorded on unamended control soil. The addition of the purple sea urchin processing waste caused an immediate and significant pH increase which was positively related to the rate of the amendment addition. After a six months equilibration period, the differences in soil pH were still evident and significant increases of electrical conductivity and available phosphorus were also detected in soils with the higher amendment rates. The number of heterotrophic and cellulolytic bacteria and actinomycetes significantly increased after amendment addition while the number of culturable fungi steadily declined. The analysis of the Biolog Community Level Physiological Profile indicated a clear influence of the purple sea urchin processing waste on the structure of the native microbial community while a significant increase of microbial functionality (i.e. dehydrogenase activity) was recorded in soil treated with the higher amendment rates (i.e. 3.0 and 5.0%). The improvement of microbial abundance and functionality as well as the change of the microbial community structure were ascribed to the pH shift induced by the P. lividus processing waste. To investigate possible effects on soil fertility, dwarf bean (Phaseolus vulgaris) and wheat (Triticum vulgare) growth were also

  2. Major element, trace element, nutrient, and radionuclide mobility in a mining by-product-amended soil.

    PubMed

    Douglas, G; Adeney, J; Johnston, K; Wendling, L; Coleman, S

    2012-01-01

    This study investigates the use of a mineral processing by-product, neutralized used acid (NUA), primarily composed of gypsum and Fe-oxyhydroxide, as a soil amendment. A 1489-d turf farm field trial assessed nutrient, trace element, and radionuclide mobility of a soil amended with ∼5% by mass to a depth of 15 cm of NUA. Average PO-P fluxes collected as subsoil leachates were 0.7 and 26.6 kg ha yr for NUA-amended and control sites, respectively, equating to a 97% reduction in PO-P loss after 434 kg P ha was applied. Total nitrogen fluxes in NUA-amended soil leachates were similarly reduced by 82%. Incorporation of NUA conferred major changes in leachate geochemistry with a diverse suite of trace elements depleted within NUA-amended leachates. Gypsum dissolution from NUA resulted in an increase from under- to oversaturation of the soil leachates for a range of Fe- and Ca-minerals including calcite and ferrihydrite, many of which have a well-documented ability to assimilate PO-P and trace elements. Isotopic analysis indicated little Pb addition from NUA. Both Sr and Nd isotope results revealed that NUA and added fertilizer became an important source of Ca to leachate and turf biomass. The NUA-amended soils retained a range of U-Th series radionuclides, with little evidence of transfer to soil leachate or turf biomass. Calculated radioactivity dose rates indicate only a small increment due to NUA amendment. With increased nutrient, trace element, and solute retention, and increased productivity, a range of potential agronomic benefits may be conferred by NUA amendment of soils, in addition to the potential to limit offsite nutrient loss and eutrophication. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. Biochar as possible long-term soil amendment for phytostabilisation of TE-contaminated soils.

    PubMed

    Bopp, Charlotte; Christl, Iso; Schulin, Rainer; Evangelou, Michael W H

    2016-09-01

    Soils contaminated by trace elements (TEs) pose a high risk to their surrounding areas as TEs can spread by wind and water erosion or leaching. A possible option to reduce TE transfer from these sites is phytostabilisation. It is a long-term and cost-effective rehabilitation strategy which aims at immobilising TEs within the soil by vegetation cover and amendment application. One possible amendment is biochar. It is charred organic matter which has been shown to immobilise metals due to its high surface area and alkaline pH. Doubts have been expressed about the longevity of this immobilising effect as it could dissipate once the carbonates in the biochar have dissolved. Therefore, in a pot experiment, we determined plant metal uptake by ryegrass (Lolium perenne) from three TE-contaminated soils treated with two biochars, which differed only in their pH (acidic, 2.80; alkaline, 9.33) and carbonate (0.17 and 7.3 %) content. Root biomass was increased by the application of the alkaline biochar due to the decrease in TE toxicity. Zinc and Cu bioavailability and plant uptake were equally reduced by both biochars, showing that surface area plays an important role in metal immobilisation. Biochar could serve as a long-term amendment for TE immobilisation even after its alkalinity effect has dissipated.

  4. Effects of biochar amendments on soil microbial biomass and activity.

    PubMed

    Zhang, H; Voroney, R P; Price, G W

    2014-11-01

    Environmental benefits reported in the literature of using biochar as a soil amendment are generally increased microbial activity and reduced greenhouse gas (GHG) emissions. This study determined the effects of amendment with biomass feedstocks (spent coffee grounds, wood pellets, and horse bedding compost) and that of biochars (700°C) produced from these feedstocks on soil microbial biomass (C and N) and activity. Soils were amended with these substrates at 0.75% by weight and incubated for up to 175 d under laboratory conditions. Biochar residual effects on soil microbial activity were also studied by amending these soils with either ammonium nitrate (NHNO, 35 mg N kg) or with glucose (864 mg C kg) plus NHNO. Soil microbial biomass C and N, net N mineralization, and CO, NO, and CH emissions were measured. Amendment with biomass feedstocks significantly increased soil microbial biomass and activity, whereas amendment with the biochars had no significant effect. Also, biochar amendment had no significant effect on either net N mineralization or NO and CH emissions from soil. These results indicate that production of biochars at this high temperature eliminated potential substrates. Microbial biomass C in biochar-amended and unamended soils was not significantly different following additions of NHNO or glucose plus NHNO, suggesting that microbial access to otherwise labile C and N was not affected. This study shows that biochars produced at 700°C, regardless of feedstock source, do not enhance soil microbial biomass or activity. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Degradation of phthalate and di-(2-ethylhexyl)phthalate by indigenous and inoculated microorganisms in sludge-amended soil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roslev, P.; Madsen, P.L.; Thyme, J.B.

    The metabolism of phthalic acid (PA) and di-(2-ethylhexyl) (DEHP) in sludge-amended agricultural soil was studied with radiotracer techniques. The initial rates of metabolism of PA and DEHP were estimated to be 731.8 and 25.6 pmol/g (dry weight) per day, respectively. Indigenous microorganisms assimilated 28 and 17% of the carbon in [{sup 14}C]PA and [{sup 14}C]DEHP, respectively, into microbial biomass. The rates of DEHP metabolism were much greater in sludge assays without soil than in assays with sludge-amended soil. Mineralization of [{sup 14}C]DEHP to {sup 14}CO{sub 2} increased fourfold after inoculation of sludge and soil samples with DEHP-degrading strain SDE 2.more » The elevated mineralization potential was maintained for more than 27 days. Experiments performed with strain SDE 2 suggested that the bioavailability and mineralization of DEHP decreased substantially in the presence of soil and sludge components. The microorganisms metabolizing PA and DEHP in sludge and sludge-amended soil were characterized by substrate-specific radiolabelling, followed by analysis of {sup 14}C-labelled phospholipid ester-linked fatty acids ({sup 14}C-PLFAs).« less

  6. Derivation of ecological criteria for copper in land-applied biosolids and biosolid-amended agricultural soils.

    PubMed

    Lu, Tao; Li, Jumei; Wang, Xiaoqing; Ma, Yibing; Smolders, Erik; Zhu, Nanwen

    2016-12-01

    The difference in availability between soil metals added via biosolids and soluble salts was not taken into account in deriving the current land-applied biosolids standards. In the present study, a biosolids availability factor (BAF) approach was adopted to investigate the ecological thresholds for copper (Cu) in land-applied biosolids and biosolid-amended agricultural soils. First, the soil property-specific values of HC5 add (the added hazardous concentration for 5% of species) for Cu 2+ salt amended were collected with due attention to data for organisms and soils relevant to China. Second, a BAF representing the difference in availability between soil Cu added via biosolids and soluble salts was estimated based on long-term biosolid-amended soils, including soils from China. Third, biosolids Cu HC5 input values (the input hazardous concentration for 5% of species of Cu from biosolids to soil) as a function of soil properties were derived using the BAF approach. The average potential availability of Cu in agricultural soils amended with biosolids accounted for 53% of that for the same soils spiked with same amount of soluble Cu salts and with a similar aging time. The cation exchange capacity was the main factor affecting the biosolids Cu HC5 input values, while soil pH and organic carbon only explained 24.2 and 1.5% of the variation, respectively. The biosolids Cu HC5 input values can be accurately predicted by regression models developed based on 2-3 soil properties with coefficients of determination (R 2 ) of 0.889 and 0.945. Compared with model predicted biosolids Cu HC5 input values, current standards (GB4284-84) are most likely to be less protective in acidic and neutral soil, but conservative in alkaline non-calcareous soil. Recommendations on ecological criteria for Cu in land-applied biosolids and biosolid-amended agriculture soils may be helpful to fill the gaps existing between science and regulations, and can be useful for Cu risk assessments in

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

    EPA Science Inventory

    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...

  8. Amendments promote the development of Lolium perenne in soils affected by historical copper smelting operations.

    PubMed

    Goecke, Paul; Ginocchio, Rosanna; Mench, Michel; Neaman, Alexander

    2011-07-01

    The Puchuncaví valley, central Chile, has been exposed to aerial emissions from a copper smelter. Nowadays, soils in the surroundings are sparsely-vegetated, acidic, and metal-contaminated, and their remediation is needed to reduce environmental risks. We assessed effectiveness of lime, fly ash, compost, and iron grit as amendments to immobilize Cu in soils and promote plant growth. Amended soils were cultivated with Lolium perenne for 60 days under controlled conditions. Total dissolved Cu and Cu2+ activity in the soil solution, ryegrass biomass, and Cu accumulation in plant tissues were measured. Addition of lime and fly ash decreased Cu concentrations and Cu2+ activity in the soil solution, increased plant biomass, and reduced shoot Cu concentration below 22 mg kg(-1) (the phytotoxicity threshold for the species). The most effective amendment with respect to the shoot biomass yield was a combination of lime and compost. Water content of the substrate and the K accumulation were positively correlated with the compost application rate. Compost combined with iron grit decreased dissolved Cu concentrations during the period of highest solubility, i.e., during the first 60 days after the compost application. However, iron grit incorporation into soils amended with lime and compost decreased the shoot biomass of ryegrass.

  9. Aided Phytostabilization of Copper Contaminated Soils with L. Perenne and Mineral Sorbents as Soil Amendments

    NASA Astrophysics Data System (ADS)

    Radziemska, Maja

    2017-09-01

    The present study was designed to assess phytostabilization strategies for the treatment of soil co-contaminated by increasing levels of copper with the application mineral amendments (chalcedonite, zeolite, dolomite). From the results it will be possible to further elucidate the benefits or potential risks derived from the application of different types of mineral amendments in the remediation of a copper contaminated soil. A glasshouse pot experiment was designed to evaluate the potential use of different amendments as immobilizing agents in the aided phytostabilization of Cu-contaminated soil using ryegrass (Lolium perenne L.). The content of trace elements in plants and total in soil, were determined using the method of spectrophotometry. All of the investigated element contents in the tested parts of L. perenne were significantly different in the case of applying mineral amendments to the soil, as well as increasing concentrations of copper. The greatest average above-ground biomass was observed for soil amended with chalcedonite. In this experiment, all analyzed metals accumulated predominantly in the roots of the tested plant. In general, applying mineral amendments to soil contributed to decreased levels of copper concentrations.

  10. Effects of Biochar amendments on soil chemistry

    NASA Astrophysics Data System (ADS)

    Mukherjee, A.; Zimmerman, A. R.

    2009-12-01

    Humans have been transforming soil composition, both accidentally and purposefully, for centuries. For example, terra preta soils found in Amazonia that are greatly enriched in organic carbon and phosphorus and have enhanced fertility relative to the surrounding depleted oxisols, seem to have been deliberately created by native pre-Colombian Indians through the addition of combusted biomass, or biochar. Biochar amendment has gained attention recently as a way to enhance soil carbon sequestration while increasing soil fertility. It may also have adsorptive properties that are useful for pollution control. Our research examines the chemical and morphological properties of biochar with the goals of understanding the origin of terra preta, as well as how biochar can best be put to use as a soil amendment. Biochar was produced from a range of parent biomass types (hardwoods, softwoods and grasses) and under a range of combustion conditions (250 to 650 oC, under air and N2). Surface areas, determined by gas sorptometry, ranged from 3 to 394 m2g-1 (for N2) and from 129 to 345 m2g-1 (for CO2) and were found to generally increase with increasing pyrolysis temperature. The pH of the biochars ranged from 1.8 to 4.5, from 6.2 to 8.7, and from 6.2 to 9.2 for the 250, 400, and 650 oC biochars, respectively, and did not vary consistently with parent biomass types. Cation exchange capacity (CEC), determined using K+ exchange, ranged between 5 to 60 cmolc kg-1, higher than most soils, and generally increased with charring temperature. Anion exchange capacity (AEC) was low or undetectable. Lastly, the isoelectric point of the chars, determined using a zeta potential analyzer, ranged from a pH of 1.3 to 1.5, indicating that the biochar surfaces will be predominantly negatively charged in soil solutions. These data are complimentary and show that, when added to soil, biochar, particularly those produced at higher temperatures, would function as a cation exchanger system. The acid

  11. Assessment of Two Solid Anaerobic Digestate Soil Amendments for Effects on Soil Quality and Biosolarization Efficacy.

    PubMed

    Fernández-Bayo, Jesús D; Achmon, Yigal; Harrold, Duff R; McCurry, Dlinka G; Hernandez, Katie; Dahlquist-Willard, Ruth M; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

    2017-05-03

    Anaerobic digestion is an organic waste bioconversion process that produces biofuel and digestates. Digestates have potential to be applied as soil amendment to improve properties for crop production including phytonutrient content and pest load. Our objective was to assess the impact of solid anaerobic digestates on weed seed inactivation and soil quality upon soil biosolarization (a pest control technique that combines solar heating and amendment-induced microbial activity). Two solid digestates from thermophilic (TD) and mesophilic (MD) digesters were tested. The solarized TD-amended samples presented significantly higher mortality of Brassica nigra (71%, P = 0.032) than its equivalent incubated at room temperature. However, biosolarization with digestate amendment led to decreased weed seed mortality in certain treatments. The plant-available water, total C, and extractable P and K were significantly increased (P < 0.05) in the incubated amended soils. The results confirm the potential of digestates as beneficial soil amendments. Further studies are needed to elucidate the impacts of digestate stability on biosolarization efficacy and soil properties.

  12. Fluorescence analysis of humic and fulvic acids from two Brazilian oxisols as affected by biosolid amendment.

    PubMed

    Bertoncini, E I; D'Orazio, V; Senesi, N; Mattiazzo, M E

    2005-03-01

    Conventional monodimensional fluorescence spectroscopy in the emission, excitation, and synchronous-scan modes and total luminescence spectroscopy have proven to be sensitive techniques for characterization and differentiation of humic acid (HA) and fulvic acid (FA) fractions isolated from an aerobically and anaerobically digested and limed biosolid, two layers of a sandy and a clayey Brazilian oxisol, and the corresponding biosolid-amended soils. The spectral patterns and the relative fluorescence intensities suggest greater molecular heterogeneity, less aromatic polycondensation, and less humification of biosolid HA and FA compared with soil HA and FA. However, the differences are smaller for the FA fractions than for the HA fractions. Fluorescence properties of soil HA and FA differ slightly as a function of soil type and soil layer. Biosolid application causes a shift to shorter wavelengths of the main fluorescence peaks and marked variation of the relative fluorescence intensities of HA and FA isolated from amended soils. These results suggest that molecular components of relatively small molecular size, with a low level of aromatic polycondensation, and low degree of humification present in biosolid HA and FA are partially and variously incorporated into amended soil HA and FA. In general, these modifications seem to be smaller in HA and FA from the clayey soil layers than in those from the sandy soil layers, possibly because of protective effects exerted by clay minerals of native soil HA and FA against disturbances caused by biosolid application.

  13. Effect of selenium-enriched organic material amendment on selenium fraction transformation and bioavailability in soil.

    PubMed

    Wang, Dan; Dinh, Quang Toan; Anh Thu, Tran Thi; Zhou, Fei; Yang, Wenxiao; Wang, Mengke; Song, Weiwei; Liang, Dongli

    2018-05-01

    To exploit the plant byproducts from selenium (Se) biofortification and reduce environmental risk of inorganic Se fertilizer, pot experiment was conducted in this study. The effects of Se-enriched wheat (Triticum aestivum L.) straw (WS + Se) and pak choi (Brassica chinensis L.) (P + Se) amendment on organo-selenium speciation transformation in soil and its bioavailability was evaluated by pak choi uptake. The Se contents of the cultivated pak choi in treatments amended with the same amount of Se-enriched wheat straw and pak choi were 1.7 and 9.7 times in the shoots and 2.3 and 6.3 times in the roots compared with control treatment. Soil respiration rate was significantly increased after all organic material amendment in soil (p < 0.05), which accelerated the mineralization of organic materials and thus resulted in soluble Se (SOL-Se), exchangeable Se (EX-Se), and fulvic acid-bound Se (FA-Se) fraction increasing by 25.2-29.2%, 9-13.8%, and 4.92-8.28%, respectively. In addition, both Pearson correlation and cluster analysis showed that EX-Se and FA-Se were better indicators for soil Se availability in organic material amendment soils. The Marquardt-Levenberg Model well described the dynamic kinetics of FA-Se content after Se-enriched organic material amendment in soil mainly because of the mineralization of organic carbon and organo-selenium. The utilization of Se in P + Se treatment was significantly higher than those in WS + Se treatment because of the different mineralization rates and the amount of FA-Se in soil. Se-enriched organic materials amendment can not only increase the availability of selenium in soil but also avoid the waste of valuable Se source. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. [Effects of simulated acid rain on decomposition of soil organic carbon and crop straw].

    PubMed

    Zhu, Xue-Zhu; Huang, Yao; Yang, Xin-Zhong

    2009-02-01

    To evaluate the effects of acid rain on the organic carbon decomposition in different acidity soils, a 40-day incubation test was conducted with the paddy soils of pH 5.48, 6.70 and 8.18. The soils were amended with 0 and 15 g x kg(-1) of rice straw, adjusted to the moisture content of 400 g x kg(-1) air-dried soil by using simulated rain of pH 6.0, 4.5, and 3.0, and incubated at 20 degrees C. The results showed that straw, acid rain, and soil co-affected the CO2 emission from soil system. The amendment of straw increased the soil CO2 emission rate significantly. Acid rain had no significant effects on soil organic carbon decomposition, but significantly affected the straw decomposition in soil. When treated with pH 3.0 acid rain, the amount of decomposed straw over 40-day incubation in acid (pH 5.48) and alkaline (pH 8.18) soils was 8% higher, while that in neutral soil (pH 6.70) was 15% lower, compared to the treatment of pH 6.0 rain. In the treatment of pH 3.0 acid rain, the decomposition rate of soil organic C in acid (pH 5.48) soil was 43% and 50% (P < 0.05) higher than that in neutral (pH 6.70) and alkaline (pH 8.18) soils, while the decomposition rate of straw in neutral soil was 17% and 16% (P < 0.05) lower than that in acid and alkaline soils, respectively.

  15. Leaching of Cu, Cd, Pb, and phosphorus and their availability in the phosphate-amended contaminated soils under simulated acid rain.

    PubMed

    Cui, Hongbiao; Zhang, Shiwen; Li, Ruyan; Yi, Qitao; Zheng, Xuebo; Hu, Youbiao; Zhou, Jing

    2017-09-01

    Phosphate amendments have been used to immobilize heavy metal-contaminated soils. However, phosphate amendments contain large amounts of phosphorus, which could leach out to potentially contaminate groundwater and surface water. A laboratory column leaching experiment was designed to study the effects of simulated acid rain (SAR) on the potential release of copper (Cu), lead (Pb), cadmium (Cd), and phosphorus (P), and their availability after immobilizing with hydroxyapatite (HAP) and potassium dihydrogen phosphate (PDP). The application of HAP and PDP enhanced the leachate electrical conductivity, total organic carbon, and pH. Higher P was found in the PDP- (>4.29 mg L -1 ) and HAP-treated (>1.69 mg L -1 ) columns than that in untreated (<0.2 mg L -1 ) columns, and they were both over the class V limit (0.4 mg L -1 ) mandated by the Chinese National Quality Standards for Surface Waters (GB 3838-2002). PDP application decreased the leachate Cu, Pb, and Cd effectively; however, HAP addition increased leachate Cu and Pb. HAP and PDP applications decreased the soil CaCl 2 -extractable and exchangeable fraction of Cu, Pb, and Cd, and increased resin P. However, eluviations transformed the heavy metals from inactive to active fractions and reduced soil labile P. These findings showed that HAP and PDP had a potential risk of excessive P-induced eutrophication. Meanwhile, more attention should be paid to the leaching loss of multiple metals because phosphate amendments might promote the leaching of some metals while immobilizing others.

  16. Effects of biochar and other amendments on the physical properties and greenhouse gas emissions of an artificially degraded soil.

    PubMed

    Mukherjee, A; Lal, R; Zimmerman, A R

    2014-07-15

    Short and long-term impacts of biochar on soil properties under field conditions are poorly understood. In addition, there is a lack of field reports of the impacts of biochar on soil physical properties, gaseous emissions and C stability, particularly in comparison with other amendments. Thus, three amendments - biochar produced from oak at 650°C, humic acid (HA) and water treatment residual - (WTR) were added to a scalped silty-loam soil @ 0.5% (w/w) in triplicated plots under soybean. Over the 4-month active growing season, all amendments significantly increased soil pH, but the effect of biochar was the greatest. Biochar significantly increased soil-C by 7%, increased sub-nanopore surface area by 15% and reduced soil bulk density by 13% compared to control. However, only WTR amendment significantly increased soil nanopore surface area by 23% relative to the control. While total cumulative CH4 and CO2 emissions were not significantly affected by any amendment, cumulative N2O emission was significantly decreased in the biochar-amended soil (by 92%) compared to control over the growing period. Considering both the total gas emissions and the C removed from the atmosphere as crop growth and C added to the soil, WTR and HA resulted in net soil C losses and biochar as a soil C gain. However, all amendments reduced the global warming potential (GWP) of the soil and biochar addition even produced a net negative GWP effect. The short observation period, low application rate and high intra-treatment variation resulted in fewer significant effects of the amendments on the physicochemical properties of the soils than one might expect indicating further possible experimentation altering these variables. However, there was clear evidence of amendment-soil interaction processes affecting both soil properties and gaseous emissions, particularly for biochar, that might lead to greater changes with additional field emplacement time. Copyright © 2014 Elsevier B.V. All rights

  17. Phosphorus mitigation during springtime runoff by amendments applied to grassed soil.

    PubMed

    Uusi-Kämppä, J; Turtola, E; Närvänen, A; Jauhiainen, L; Uusitalo, R

    2012-01-01

    Permanent grass vegetation on sloping soils is an option to protect fields from erosion, but decaying grass may liberate considerable amounts of dissolved reactive P (DRP) in springtime runoff. We studied the effects of freezing and thawing of grassed soil on surface runoff P concentrations by indoor rainfall simulations and tested whether the peak P concentrations could be reduced by amending the soil with P-binding materials containing Ca or Fe. Forty grass-vegetated soil blocks (surface area 0.045 m, depth 0.07 m) were retrieved from two permanent buffer zones on a clay and loam soil in southwest Finland. Four replicates were amended with either: (i) gypsum from phosphoric acid processing (CaSO × 2HO, 6 t ha), (ii) chalk powder (CaCO, 3.3 t ha), (iii) Fe-gypsum (6 t ha) from TiO processing, or (iv) granulated ferric sulfate (Fe[SO], 0.7 t ha), with four replicates serving as untreated controls. Rainfall (3.3 h × 5 mm h) was applied on presaturated samples set at a slope of 5% and the surface runoff was analyzed for DRP, total dissolved P (TDP), total P (TP), and suspended solids. Rainfall simulation was repeated twice after the samples were frozen. Freezing and thawing of the samples increased the surface runoff DRP concentration of the control treatment from 0.19 to 0.46 mg L, up to 2.6-3.7 mg L, with DRP being the main P form in surface runoff. Compared with the controls, surface runoff from soils amended with Fe compounds had 57 to 80% and 47 to 72% lower concentrations of DRP and TP, respectively, but the gypsum and chalk powder did not affect the P concentrations. Thus, amendments containing Fe might be an option to improve DRP retention in, e.g., buffer zones. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  18. Urease gene-containing Archaea dominate autotrophic ammonia oxidation in two acid soils.

    PubMed

    Lu, Lu; Jia, Zhongjun

    2013-06-01

    The metabolic traits of ammonia-oxidizing archaea (AOA) and bacteria (AOB) interacting with their environment determine the nitrogen cycle at the global scale. Ureolytic metabolism has long been proposed as a mechanism for AOB to cope with substrate paucity in acid soil, but it remains unclear whether urea hydrolysis could afford AOA greater ecological advantages. By combining DNA-based stable isotope probing (SIP) and high-throughput pyrosequencing, here we show that autotrophic ammonia oxidation in two acid soils was predominately driven by AOA that contain ureC genes encoding the alpha subunit of a putative archaeal urease. In urea-amended SIP microcosms of forest soil (pH 5.40) and tea orchard soil (pH 3.75), nitrification activity was stimulated significantly by urea fertilization when compared with water-amended soils in which nitrification resulted solely from the oxidation of ammonia generated through mineralization of soil organic nitrogen. The stimulated activity was paralleled by changes in abundance and composition of archaeal amoA genes. Time-course incubations indicated that archaeal amoA genes were increasingly labelled by (13) CO2 in both microcosms amended with water and urea. Pyrosequencing revealed that archaeal populations were labelled to a much greater extent in soils amended with urea than water. Furthermore, archaeal ureC genes were successfully amplified in the (13) C-DNA, and acetylene inhibition suggests that autotrophic growth of urease-containing AOA depended on energy generation through ammonia oxidation. The sequences of AOB were not detected, and active AOA were affiliated with the marine Group 1.1a-associated lineage. The results suggest that ureolytic N metabolism could afford AOA greater advantages for autotrophic ammonia oxidation in acid soil, but the mechanism of how urea activates AOA cells remains unclear. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  19. Addition of organic amendments contributes to C sequestration in trace element contaminated soils.

    NASA Astrophysics Data System (ADS)

    del Mar Montiel Rozas, María; Panettier, Marco; Madejón Rodríguez, Paula; Madejón Rodríguez, Engracia

    2015-04-01

    Nowadays, the study of global C cycle and the different natural sinks of C have become especially important in a climate change context. Fluxes of C have been modified by anthropogenic activities and, presently, the global objective is the decrease of net CO2 emission. For this purpose, many studies are being conducted at local level for evaluate different C sequestration strategies. These techniques must be, in addition to safe in the long term, environmentally friendly. Restoration of contaminated and degraded areas is considered as a strategy for SOC sequestration. Our study has been carried out in the Guadiamar Green Corridor (Seville, Spain) affected by the Aznalcóllar mining accident. This accident occurred 16 years ago, due to the failure of the tailing dam which contained 4-5 million m3 of toxic tailings (slurry and acid water).The affected soils had a layer of toxic sludge containing heavy metals as As, Cd, Cu, Pb and Zn. Restoration techniques began to be applied just after the accident, including the removal of the toxic sludge and a variable layer of topsoil (10-30 cm) from the surface. In a second phase, in a specific area (experimental area) of the Green Corridor the addition of organic amendments (Biosolid compost (BC) and Leonardite (LE), a low grade coal rich in humic acids) was carried out to increase pH, organic matter and fertility in a soil which lost its richest layer during the clean-up operation. In our experimental area, half of the plots (A) received amendments for four years (2002, 2003, 2006 and 2007) whereas the other half (B) received amendments only for two years (2002-2003). To compare, plots without amendments were also established. Net balance of C was carried out using values of Water Soluble Carbon (WSC) and Total Organic Carbon (TOC) for three years (2012, 2013 and 2015). To eliminate artificial changes carried out in the plots, amendment addition and withdrawal of biomass were taken into account to calculate balance of kg TOC

  20. Phosphorus release from dairy manure, the manure-derived biochar, and their amended soil: effects of phosphorus nature and soil property.

    PubMed

    Liang, Yuan; Cao, Xinde; Zhao, Ling; Xu, Xiaoyun; Harris, Willie

    2014-07-01

    Land application of animal manure often risks excessive phosphorus (P) release into the surrounding water. The aim of this study was to convert the dairy manure into biochar, followed by their application into soil, and then to investigate P release from the manure and its derived biochar as well as from the manure- and biochar-amended soil. The results showed that P release was reduced when the manure was converted into biochar due to formation of less-soluble whitlockite [(Ca, Mg)(PO)]. The cumulative P released from biochar over 240 h was 0.26 g kg, a 76% reduction of that from the manure (1.07 g kg). The kinetic release of P from the manure was determined by the fast desorption process and was better fitted to Elovich equation, whereas P release from biochar was initially controlled by the diffusion process and then by slow but steady dissolution of (Ca,Mg)(PO), following the parabolic diffusion and linear models, respectively. When the manure or biochar was incorporated into the soil, P release in the CaCl and simulated acid rain water extraction from biochar-amended soil was consistently lower than that from the manure-amended soil during 210-d incubation. The lower P release in the biochar-amended soil was determined by stable P form (Ca, Mg)(PO) in the biochar itself, but less from the soil property effect. Results indicated that initial high P release from manure can be mitigated by converting the manure into biochar. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Soil management of copper mine tailing soils--sludge amendment and tree vegetation could improve biological soil quality.

    PubMed

    Asensio, Verónica; Covelo, Emma F; Kandeler, Ellen

    2013-07-01

    Mine soils at the depleted copper mine in Touro (Northwest Spain) are physico-chemically degraded and polluted by chromium and copper. To increase the quality of these soils, some areas at this mine have been vegetated with eucalyptus or pines, amended with sludges, or received both treatments. Four sites were selected at the Touro mine tailing in order to evaluate the effect of these different reclamation treatments on the biological soil quality: (1) Control (untreated), (2) Forest (vegetated), (3) Sludge (amended with sludges) and (4) Forest+Sludge (vegetated and amended). The new approach of the present work is that we evaluated the effect of planting trees or/and amending with sludges on the biological soil quality of mine sites polluted by metals under field conditions. The addition of sludges to mine sites recovered the biological quality of the soil, while vegetating with trees did not increase microbial biomass and function to the level of unpolluted sites. Moreover, amending with sludges increased the efficiency of the soil's microbial community to metabolize C and N, which was indicated by the decrease of the specific enzyme activities and the increase in the ratio Cmic:Nmic (shift towards predominance of fungi instead of bacteria). However, the high Cu and Cr concentrations still have negative influence on the microorganisms in all the treated soils. For the future remediation of mine soils, we recommend periodically adding sludge and planting native legume species. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Mineralization of soil organic matter in biochar amended agricultural landscape

    NASA Astrophysics Data System (ADS)

    Chintala, R.; Clay, D. E.; Schumacher, T. E.; Kumar, S.; Malo, D. D.

    2015-12-01

    Pyrogenic biochar materials have been identified as a promising soil amendment to enhance climate resilience, increase soil carbon recalcitrance and achieve sustainable crop production. A three year field study was initiated in 2013 to study the impact of biochar on soil carbon and nitrogen storage on an eroded Maddock soil series - Sandy, Mixed, Frigid Entic Hapludolls) and deposition Brookings clay loam (Fine-Silty, Mixed, Superactive, Frigid Pachic Hapludolls) landscape positions. Three biochars produced from corn stover (Zea mays L.), Ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) were incorporated at 9.75 Mg ha-1 rate (≈7.5 cm soil depth and 1.3 g/cm3 soil bulk density) with a rototiller. The changes in chemical fractionation of soil carbon (soluble C, acid hydrolyzable C, total C, and δ13 C) and nitrogen (soluble N, acid hydrolyzable N, total N, and δ14 N) were monitored for two soil depths (0-7.5 and 7.5 - 15 cm). Soluble and acid hydrolyzable fractions of soil C and N were influenced by soil series and were not significantly affected by incorporation of biochars. Based on soil and plant samples to be collected in the fall of 2015, C and N budgets are being developed using isotopic and non-isotopic techniques. Laboratory studies showed that the mean residence time for biochars used in this study ranged from 400 to 666 years. Laboratory and field studies will be compared in the presentation.

  3. Chloropicrin Emission Reduction by Soil Amendment with Biochar

    PubMed Central

    Wang, Qiuxia; Yan, Dongdong; Liu, Pengfei; Mao, Liangang; Wang, Dong; Fang, Wensheng; Li, Yuan; Ouyang, Canbin; Guo, Meixia; Cao, Aocheng

    2015-01-01

    Biochar has sorption capacity, and can be used to enhance the sequestration of volatile organic contaminants such as pesticides in soil. Chloropicrin (CP) is an important soil fumigant for the production of many fruit and vegetable crops, but its emissions must be minimized to reduce exposure risks and air pollution. The objective of this study was to determine the capacity of biochar to adsorb CP and the effect of biochar amendments to soil on CP emission, concentration in the soil gas phase, degradation in soil and CP bioactivity for controlling soil borne pests. CP emission and concentration in the soil air phase were measured from packed soil columns after fumigant injection at 20-cm depth and application of selected doses of biocharto the surface 5 cm soil. Laboratory incubation and fumigation experiments were conducted to determine the capacity of biochar to adsorb CP, the effects on CP degradation and, separately, CP’s bioactivity on soil borne pests in soil amended with biochar. Biochar amendment at 2% to 5% (w/w) greatly reduced total CP emission losses by 85.7% - 97.7% compared to fumigation without biochar. CP concentrations in the soil gas-phase, especially in the top 5 cm of soil, were reduced within 48 h following application. The half-life of CP decreased from 13.6 h to 6.4 h as the biochar rate increased from 0% to 5%. CP and its metabolite (dichloronitromethane) both degraded more rapidly in pure biochar than in soil. The biochar used in the present study had a maximum adsorption capacity for CP of less than 5 mg g-1. There were no negative effects on pathogen and nematode control when the biochar used in this study was less than 1% (on a weight basis) in soil. Biochar amendment to soil reduced the emissions of CP. CP concentrations in the top 5 cm of soil gas-phase were reduced. CP degradation was accelerated with the addition of biochar. The biochar used in the present study had a low adsorption capacity for CP. There were no negative effects

  4. Evaluation of soil amendments as a remediation alternative for cadmium-contaminated soils under cacao plantations.

    PubMed

    Chavez, E; He, Z L; Stoffella, P J; Mylavarapu, R; Li, Y; Baligar, V C

    2016-09-01

    Elevated plant-available cadmium (Cd) in soils results in contamination to cacao (Theobroma cacao L) beans. Effectiveness of vermicompost and zeolite in reducing available Cd in three cacao-growing soils was studied under laboratory conditions. Sorption-desorption experiments were conducted in soils and amendments. Cadmium was added at 0 or 5 mg kg(-1) (spiked), then, amendments were incorporated at 0, 0.5, or 2 %. Amended soils were incubated at room temperature for 28 days. Plant-available Cd was determined using 0.01 M CaCl2 (WSE) and Mehlich 3 (M3) extraction procedures in subsamples taken from individual bags at six time intervals. Soils and amendments displayed different sorption characteristics and a better fit was attained with Freundlich model (R (2) > 0.82). Amendments were ineffective in reducing extractable Cd in non-spiked soils. In Cd-spiked soils, vermicompost at 2 % significantly reduced WSE-Cd (P < 0.01) from 3.36, 0.54, and 0.38 mg kg(-1) to values lower that instrument's detection in all the three soils and significantly diminished M3-extractable Cd (P < 0.05) from 4.62 to 4.11 mg kg(-1) in only one soil. Vermicompost at 0.5 % significantly decreased WSE-Cd (P < 0.01) from 3.04 and 0.31 to 1.69 and 0.20 mg kg(-1), respectively, in two soils with low sorption capacity for Cd. In contrast, zeolite failed to reduce WSE- or M3-extractable Cd in all studied soils. A negative correlation occurred between soil pH and WSE-Cd (r > -0.89, P < 0.01). The decrease in WSE-Cd appears to be associated with the increase in pH of the vermicompost-amended soils.

  5. Effects of biochar amendment on geotechnical properties of landfill cover soil.

    PubMed

    Reddy, Krishna R; Yaghoubi, Poupak; Yukselen-Aksoy, Yeliz

    2015-06-01

    Biochar is a carbon-rich product obtained when plant-based biomass is heated in a closed container with little or no available oxygen. Biochar-amended soil has the potential to serve as a landfill cover material that can oxidise methane emissions for two reasons: biochar amendment can increase the methane retention time and also enhance the biological activity that can promote the methanotrophic oxidation of methane. Hydraulic conductivity, compressibility and shear strength are the most important geotechnical properties that are required for the design of effective and stable landfill cover systems, but no studies have been reported on these properties for biochar-amended landfill cover soils. This article presents physicochemical and geotechnical properties of a biochar, a landfill cover soil and biochar-amended soils. Specifically, the effects of amending 5%, 10% and 20% biochar (of different particle sizes as produced, size-20 and size-40) to soil on its physicochemical properties, such as moisture content, organic content, specific gravity and pH, as well as geotechnical properties, such as hydraulic conductivity, compressibility and shear strength, were determined from laboratory testing. Soil or biochar samples were prepared by mixing them with 20% deionised water based on dry weight. Samples of soil amended with 5%, 10% and 20% biochar (w/w) as-is or of different select sizes, were also prepared at 20% initial moisture content. The results show that the hydraulic conductivity of the soil increases, compressibility of the soil decreases and shear strength of the soil increases with an increase in the biochar amendment, and with a decrease in biochar particle size. Overall, the study revealed that biochar-amended soils can possess excellent geotechnical properties to serve as stable landfill cover materials. © The Author(s) 2015.

  6. Responses of soil biota to organic amendments in stripmine spoils in Northwestern New Mexico

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elkins, N.Z.; Parker, L.W.; Aldon, E.

    The effects of organic amendments and topsoiling on the soil biota and decomposition were examined in order to evaluate the relative efficacy of the amendments in restarting soil processes. Decomposition of barley straw (Hordeum vulgare) and populations of soil biota on strip coal-mine spoils in northwestern New Mexico were studied. The spoils had been amended with straw mulch, bark, topsoil, or no organic additives. Decomposition rates were highest in the unmined area and the bark, amended spoils, and lowest on the topsoil amendment and unamended spoil. Few differences were observed in the populations of soil microflora. Where differences were observed,more » the bark-amended spoils had the highest populations and biomass. Soil microflora activity, as indicated by decomposition rates, was enhanced by bark amendment. Soil microfaunal populations were highest on the bark-amended spoils and unmined soil. Important soil mites (soil Acari), the oribatids, were found only in the bark-amended spoils and the unmined soils. These studies suggest that addition of selected organic amendments (bark) to mine spoils may be as effective in developing a soil as the more expensive topsoil/mulch procedures currently used in reclamation procedures. 25 references.« less

  7. Degradation of dimethyl disulphide in soil with or without biochar amendment.

    PubMed

    Han, Dawei; Yan, Dongdong; Cao, Aocheng; Fang, Wensheng; Liu, Pengfei; Li, Yuan; Ouyang, Canbin; Wang, Qiuxia

    2017-09-01

    Dimethyl disulphide (DMDS) is a new and effective alternative to methyl bromide for soil fumigation. The effect of biochar on the fate of DMDS in soil is not fully understood. The objective of this study was to determine the degradation kinetics of DMDS in different soils and evaluate the effect of biochar amendment on DMDS degradation using incubation experiments. The degradation half-life of DMDS was between 1.05 and 6.66 days under non-sterile conditions, and 12.63 to 22.67 days under sterile conditions in five types of soil. Seven out of the eight tested biochar amendments (BC-2 to BC-8) delayed the degradation of DMDS in soil, increasing the half-life of DMDS in Fangshan soil from 1.05 to 1.16-5.87 days following amendment with 1% (w/w) biochar. The degradation rate of DMDS in Fangshan soil accelerated as the amendment rate of BC-1 increased, and decreased as the amendment rate of BC-7 increased. Biodegradation is an important degradation route for DMDS in soil, and DMDS degraded faster in alkaline soil. The effects of biochar amendments on DMDS degradation in soil are determined by complex multiple factors (such as surface area, pH and physicochemical composition), rather than by any single property of biochar. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Biochar amendment to soil changes dissolved organic matter content and composition.

    PubMed

    Smebye, Andreas; Alling, Vanja; Vogt, Rolf D; Gadmar, Tone C; Mulder, Jan; Cornelissen, Gerard; Hale, Sarah E

    2016-01-01

    Amendments of biochar, a product of pyrolysis of biomass, have been shown to increase fertility of acidic soils by enhancing soil properties such as pH, cation-exchange-capacity and water-holding-capacity. These parameters are important in the context of natural organic matter contained in soils, of which dissolved organic matter (DOM) is the mobile and most bioavailable fraction. The effect of biochar on the content and composition of DOM in soils has received little research attention. This study focuses on the effects of amendments of two different biochars to an acidic acrisol and a pH-neutral brown soil. A batch experiment showed that mixing biochar with the acrisols at a 10 wt.% dose increased the pH from 4.9 to 8.7, and this resulted in a 15-fold increase in the dissolved organic carbon concentration (from 4.5 to 69 mg L(-1)). The pH-increase followed the same trend as the release of DOM in the experiment, causing higher DOM solubility and desorption of DOM from mineral sites. The binding to biochar of several well-characterised reference DOM materials was also investigated and results showed a higher sorption of aliphatic DOM to biochar than aromatic DOM, with DOM-water partitioning coefficients (Kd-values) ranging from 0.2 to 590 L kg(-1). A size exclusion occurring in biochar's micropores, could result in a higher sorption of smaller aliphatic DOM molecules than larger aromatic ones. These findings indicate that biochar could increase the leaching of DOM from soil, as well as change the DOM composition towards molecules with a larger size and higher aromaticity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Behavior of oxyfluorfen in soils amended with different sources of organic matter. Effects on soil biology.

    PubMed

    Gómez, Isidoro; Rodríguez-Morgado, Bruno; Parrado, Juan; García, Carlos; Hernández, Teresa; Tejada, Manuel

    2014-05-30

    We performed a laboratory study on the effect of oxyfluorfen at a rate of 4lha(-1) on biological properties of a soil amended with four organic wastes (two biostimulants/biofertilizers, obtained from rice bran, RB1 and RB2; municipal solid waste, MSW; and sheep manure, SM). Soil was mixed with SM at a rate of 1%, MSW at a rate of 0.52%, RB1 at a rate of 0.39% and RB2 at a rate of 0.30%, in order to apply the same amount of organic matter to the soil. The enzymatic activities and microbial community in the soil were determined during the incubation times. The application of RB1 and RB2 to soil without oxyfluorfen increased the enzymatic activities and biodiversity, peaking at day 10 of the incubation period. This stimulation was higher in the soil amended with RB2 than in that amended with RB1. In SM and CF-amended soils, the stimulation of enzymatic activities and soil biodiversity increased during the experiment. The application of herbicide in organic-amended soils decreased the inhibition of soil enzymatic activities and soil biodiversity. Possibly the low molecular weight protein content easily assimilated by soil microorganisms and the higher fat content in the biostimulants/biofertilizers are responsible for the lower inhibition of these soil biological properties. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments.

    PubMed

    Duquène, L; Vandenhove, H; Tack, F; Meers, E; Baeten, J; Wannijn, J

    2009-02-15

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH4-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg(-1) dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years.

  11. [Study the restoration technology of concentrated application-natural diffusion about amendments of acidified soil of hilly woodland].

    PubMed

    Fang, Xiong; Liu, Ju-Xiu; Yin, Guang-Cai; Zhao, Liang; Liu, Shi-Zhong; Chu, Guo-Wei; Li, Yi-Yong

    2013-01-01

    Through concentrated application of lime, sewage sludge and lime + sewage sludge on the sloping top of the hilly woodlands, the restoration effects of the three soil amendments on the acidified soil of hilly woodland were studied. The results showed that: (1) Joint application of sewage sludge + lime can significantly (P < 0.05) decrease soil acidity, promote the rapid increase in soil organic matter and nitrogen content, increase soil cation exchange capacity, and effectively improve acidified soil. (2) Through natural diffusion mechanisms of surface and subsurface runoff, a large area of acidified soil of hilly woodlands can be restored by concentrated application of soil amendments on the sloping top of the hilly woodlands. (3) It is conducive to solve the pollution problems of the urban sewage sludge by using municipal sewage sludge to restore acidified soil, but only for the restoration of acidified soil of timber forest.

  12. Effect of chemical amendments on remediation of potentially toxic trace elements (PTEs) and soil quality improvement in paddy fields.

    PubMed

    Kim, Sung Chul; Hong, Young Kyu; Oh, Se Jin; Oh, Seung Min; Lee, Sang Phil; Kim, Do Hyung; Yang, Jae E

    2017-04-01

    Remediation of potentially toxic trace elements (PTEs) in paddy fields is fundamental for crop safety. In situ application of chemical amendments has been widely adapted because of its cost-effectiveness and environmental safety. The main purpose of this research was to (1) evaluate the reduction in dissolved concentrations of cadmium (Cd) and arsenic (As) with the application of chemical amendments and (2) monitor microbial activity in the soil to determine the remediation efficiency. Three different chemical amendments, lime stone, steel slag, and acid mine drainage sludge, were applied to paddy fields, and rice (Oryza sativa L. Milyang 23) was cultivated. The application of chemical amendments immobilized both Cd and As in soil. Between the two PTEs, As reduction was significant (p < 0.05) with the addition of chemical amendments, whereas no significant reduction was observed for Cd than that for the control. Among six soil-related variables, PTE concentration showed a negative correlation with soil pH (r = -0.70 for As and r = -0.54 for Cd) and soil respiration (SR) (r = -0.88 for As and r = -0.45 for Cd). This result indicated that immobilization of PTEs in soil is dependent on soil pH and reduces PTE toxicity. Overall, the application of chemical amendments could be utilized for decreasing PTE (As and Cd) bioavailability and increasing microbial activity in the soil.

  13. Fuzzy indicator approach: development of impact factor of soil amendments

    USDA-ARS?s Scientific Manuscript database

    Soil amendments have been shown to be useful for improving soil condition, but it is often difficult to make management decisions as to their usefulness. Utilization of Fuzzy Set Theory is a promising method for decision support associated with utilization of soil amendments. In this article a tool ...

  14. Microbial response to salinity stress in a tropical sandy soil amended with native shrub residues or inorganic fertilizer.

    PubMed

    Sall, Saïdou Nourou; Ndour, Ndèye Yacine Badiane; Diédhiou-Sall, Siré; Dick, Richard; Chotte, Jean-Luc

    2015-09-15

    Soil degradation and salinization caused by inappropriate cultivation practices and high levels of saltwater intrusion are having an adverse effect on agriculture in Central Senegal. The residues of Piliostigma reticulatum, a local shrub that coexists with crops, were recently shown to increase particulate organic matter and improve soil quality and may be a promising means of alleviating the effects of salinization. This study compared the effects of inorganic fertilizer and P. reticulatum residues on microbial properties and the ability of soil to withstand salinity stress. We hypothesized that soils amended with P. reticulatum would be less affected by salinity stress than soils amended with inorganic fertilizer and control soil. Salinity stress was applied to soil from a field site that had been cultivated for 5 years under a millet/peanut crop rotation when microbial biomass, phospholipid fatty acid (PLFA) community profile, catabolic diversity, microbial activities were determined. Microbial biomass, nitrification potential and dehydrogenase activity were higher by 20%, 56% and 69% respectively in soil with the organic amendment. With salinity stress, the structure and activities of the microbial community were significantly affected. Although the biomass of actinobacteria community increased with salinity stress, there was a substantial reduction in microbial activity in all soils. The soil organically amended was, however, less affected by salinity stress than the control or inorganic fertilizer treatment. This suggests that amendment using P. reticulatum residues may improve the ability of soils to respond to saline conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Phosphate reactivity in long-term poultry litter-amended southern Delaware sandy soils

    USGS Publications Warehouse

    Arai, Y.; Livi, K.J.T.; Sparks, D.L.

    2005-01-01

    Eutrophication caused by dissolved P from poultry litter (PL)-amended agricultural soils has been a serious environmental concern in the Delaware-Maryland-Virginia Peninsula (Delmarva), USA. To evaluate state and federal nutrient management strategies for reducing the environmental impact of soluble P from long-term PL-amended Delaware (DE) soils, we investigated (i) inorganic P speciation; (ii) P adsorption capacity; and (iii) the extent of P desorption. Although the electron microprobe (EMP) analyses showed a strong correlation between P and Al/Fe, crystalline Al/Fe-P precipitates were not detected by x-ray diffraction (XRD). Instead, the inorganic P fractionation analyses showed high levels of oxalate extractable P, Al, and Fe fractions (615-858, 1215-1478, and 337-752 mg kg-1, respectively), which were susceptible to slow release during the long-term (30-d) P desorption experiments at a moderately acidic soil pHwater. The labile P in the short-term (24-h) desorption studies was significantly associated with oxalate and F extractable Fe and Al, respectively. This was evident in an 80% reduction maximum in total desorbable P from NH4 oxalate/F pretreated soils. In the adsorption experiments, P was strongly retained in soils at near targeted pH of lime (???6.0), but P adsorption gradually decreased with decreasing pH near the soil pHwater (???5.0). The overall findings suggest that P losses from the can be suppressed by an increase in the P retention capacity of soils via (i) an increase in the number of lime applications to maintain soil pHwater at near targeted pH values, and/or (ii) alum/iron sulfate amendments to provide additional Al- and Fe-based adsorbents. ?? Soil Science Society of America.

  16. Soil contamination with cadmium, consequences and remediation using organic amendments.

    PubMed

    Khan, Muhammad Amjad; Khan, Sardar; Khan, Anwarzeb; Alam, Mehboob

    2017-12-01

    Cadmium (Cd) contamination of soil and food crops is a ubiquitous environmental problem that has resulted from uncontrolled industrialization, unsustainable urbanization and intensive agricultural practices. Being a toxic element, Cd poses high threats to soil quality, food safety, and human health. Land is the ultimate source of waste disposal and utilization therefore, Cd released from different sources (natural and anthropogenic), eventually reaches soil, and then subsequently bio-accumulates in food crops. The stabilization of Cd in contaminated soil using organic amendments is an environmentally friendly and cost effective technique used for remediation of moderate to high contaminated soil. Globally, substantial amounts of organic waste are generated every day that can be used as a source of nutrients, and also as conditioners to improve soil quality. This review paper focuses on the sources, generation, and use of different organic amendments to remediate Cd contaminated soil, discusses their effects on soil physical and chemical properties, Cd bioavailability, plant uptake, and human health risk. Moreover, it also provides an update of the most relevant findings about the application of organic amendments to remediate Cd contaminated soil and associated mechanisms. Finally, future research needs and directions for the remediation of Cd contaminated soil using organic amendments are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Nitrate capture and slow release in biochar amended compost and soil.

    PubMed

    Hagemann, Nikolas; Kammann, Claudia I; Schmidt, Hans-Peter; Kappler, Andreas; Behrens, Sebastian

    2017-01-01

    Slow release of nitrate by charred organic matter used as a soil amendment (i.e. biochar) was recently suggested as potential mechanism of nutrient delivery to plants which may explain some agronomic benefits of biochar. So far, isolated soil-aged and composted biochar particles were shown to release considerable amounts of nitrate only in extended (>1 h) extractions ("slow release"). In this study, we quantified nitrate and ammonium release by biochar-amended soil and compost during up to 167 h of repeated extractions in up to six consecutive steps to determine the effect of biochar on the overall mineral nitrogen retention. We used composts produced from mixed manures amended with three contrasting biochars prior to aerobic composting and a loamy soil that was amended with biochar three years prior to analysis and compared both to non-biochar amended controls. Composts were extracted with 2 M KCl at 22°C and 65°C, after sterilization, after treatment with H2O2, after removing biochar particles or without any modification. Soils were extracted with 2 M KCl at 22°C. Ammonium was continuously released during the extractions, independent of biochar amendment and is probably the result of abiotic ammonification. For the pure compost, nitrate extraction was complete after 1 h, while from biochar-amended composts, up to 30% of total nitrate extracted was only released during subsequent extraction steps. The loamy soil released 70% of its total nitrate amount in subsequent extractions, the biochar-amended soil 58%. However, biochar amendment doubled the amount of total extractable nitrate. Thus, biochar nitrate capture can be a relevant contribution to the overall nitrate retention in agroecosystems. Our results also indicate that the total nitrate amount in biochar amended soils and composts may frequently be underestimated. Furthermore, biochars could prevent nitrate loss from agroecosystems and may be developed into slow-release fertilizers to reduce global N

  18. Nitrate capture and slow release in biochar amended compost and soil

    PubMed Central

    Kammann, Claudia I.; Schmidt, Hans-Peter; Kappler, Andreas; Behrens, Sebastian

    2017-01-01

    Slow release of nitrate by charred organic matter used as a soil amendment (i.e. biochar) was recently suggested as potential mechanism of nutrient delivery to plants which may explain some agronomic benefits of biochar. So far, isolated soil-aged and composted biochar particles were shown to release considerable amounts of nitrate only in extended (>1 h) extractions (“slow release”). In this study, we quantified nitrate and ammonium release by biochar-amended soil and compost during up to 167 h of repeated extractions in up to six consecutive steps to determine the effect of biochar on the overall mineral nitrogen retention. We used composts produced from mixed manures amended with three contrasting biochars prior to aerobic composting and a loamy soil that was amended with biochar three years prior to analysis and compared both to non-biochar amended controls. Composts were extracted with 2 M KCl at 22°C and 65°C, after sterilization, after treatment with H2O2, after removing biochar particles or without any modification. Soils were extracted with 2 M KCl at 22°C. Ammonium was continuously released during the extractions, independent of biochar amendment and is probably the result of abiotic ammonification. For the pure compost, nitrate extraction was complete after 1 h, while from biochar-amended composts, up to 30% of total nitrate extracted was only released during subsequent extraction steps. The loamy soil released 70% of its total nitrate amount in subsequent extractions, the biochar-amended soil 58%. However, biochar amendment doubled the amount of total extractable nitrate. Thus, biochar nitrate capture can be a relevant contribution to the overall nitrate retention in agroecosystems. Our results also indicate that the total nitrate amount in biochar amended soils and composts may frequently be underestimated. Furthermore, biochars could prevent nitrate loss from agroecosystems and may be developed into slow-release fertilizers to reduce global N

  19. Phytoavailability of Cd and Pb in crop straw biochar-amended soil is related to the heavy metal content of both biochar and soil.

    PubMed

    Shen, Xin; Huang, Dao-You; Ren, Xue-Fei; Zhu, Han-Hua; Wang, Shuai; Xu, Chao; He, Yan-Bing; Luo, Zun-Chang; Zhu, Qi-Hong

    2016-03-01

    Crop straw biochar incorporation may be a sustainable method of amending soil, but feedstock-related Cd and Pb content is a major concern. We investigated the effects of heavy metal-rich (RC) and -free biochar (FC) on the phytoavailability of Cd and Pb in two acidic metalliferous soils. Biochar significantly increased soil pH and improved plant growth. Pb in soil and plant tissues significantly decreased after biochar application, and a similar pattern was observed for Cd after FC application. RC significantly increased NH4NO3-extractable Cd in both lightly contaminated (YBS) and heavily contaminated soils (RS). The Cd content of plants grown on YBS increased, whereas it decreased on RS. The Cd and Pb input-output balance suggested that RC application to YBS might induce a soil Cd accumulation risk. Therefore, identifying heavy metal contamination in biochar is crucial before it is used as a soil amendment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Chemically assisted phytoextraction: a review of potential soil amendments for increasing plant uptake of heavy metals.

    PubMed

    Meers, E; Tack, F M G; Van Slycken, S; Ruttens, A; Du Laing, G; Vangronsveld, J; Verloo, M G

    2008-01-01

    The contamination of soils by trace metals has been an unfortunate sideeffect of industrialization. Some of these contaminants can interfere with vulnerable enduses of soil, such as agriculture or nature, already at relatively low levels of contamination. Reversely, conventional civil-technical soil-remediation techniques are too expensive to remediate extended areas of moderately contaminated soil. Phytoextraction has been proposed as a more economic complementary approach to deal with this specific niche of soil contamination. However, phytoextraction has been shown to be a slow-working process due to the low amounts of metals that can be annually removed from the soil under normal agronomic conditions. Therefore, extensive research has been conducted on process optimization by means of chemically improving plant availability and the uptake of heavy metals. A wide range of potential amendments has been proposed in the literature, with considerable attention being spent on aminopolycarboxylic acids such as ethylenediaminetetraacetic acid (EDTA). However, these compounds have received increasing criticism due to their environmental persistence and associated risks for leaching. This review presents an overview of potential soil amendments that can be employed for enhancing metal uptake by phytoextraction crops, with a distinct focus on more degradable alternatives to persistent compounds such as EDTA.

  1. Effects of organic amendments and mulches on soil microbial communities in quarry restoration under semiarid climate

    NASA Astrophysics Data System (ADS)

    Luna Ramos, Lourdes; Pastorelli, Roberta; Miralles Mellado, Isabel; Fabiani, Arturo; Bastida López, Felipe; Hernández Fernández, María Teresa; García Izquierdo, Carlos; Solé Benet, Albert

    2015-04-01

    Mining activities generate loss of the quality of the environment and landscape specially in arid and semiarid Mediterranean regions. A precondition for ecosystem reclamation in such highly disturbed mining areas is the development of functional soils with appropriate levels of organic matter. In an experimental soil restoration in limestone quarries from Sierra de Gádor (Almería), SE Spain, 9 plots 15 x 5 m were prepared to test organic amendments (compost from solid urban residues-DOW-, sludge from urban water treatment-SS-, control-NA-) and different mulches (fine gravel-GM-, wood chips-WM-, control-NM-) with the aim to improve soil/substrate properties and to reduce evaporation and erosion. In each experimental plot, 75 native plants (Macrochloa tenacissima, Anthyllis terniflora and Anthyllis cytisoides) were planted. After 5 years from the start of the experiment, we evaluated how microbial community composition responded to the organic amendments and mulches. Microbial community composition of both bacteria and fungi was determined by phospholipid fatty acid (PLFA) and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprinting. The results of the two-way ANOVA showed that PLFAs were significantly affected by organic amendments but not by the mulches or interaction of both factors. Experimental plots with DOW showed significantly higher level of fungal PLFAs than those with SS and NA, even higher than the reference undisturbed soil. However, any plot with organic amendments did not reach the content of bacterial PLFAs of the reference soils. The bacterial diversity (evaluated by diversity indices calculated from DGGE profiles) was greater in soil samples taken under NA and GM. Comparing these indices in fungal DGGE, we found greater values for soil samples taken under DOW and without mulches. Results from UPGMA analysis showed significant differences in the structure of soil bacterial communities from the different treatments

  2. Various soil amendments and environmental wastes affect the (im)mobilization and phytoavailability of potentially toxic elements in a sewage effluent irrigated sandy soil.

    PubMed

    Shaheen, Sabry M; Shams, Mohamed S; Khalifa, Mohamed R; El-Dali, Mohamed A; Rinklebe, Jörg

    2017-08-01

    Contamination of long-term sewage effluent irrigated soils by potentially toxic elements (PTEs) is a serious concern due to its high environmental and health risk. Our scientific hypothesis is that soil amendments can cause contradictory effects on the element mobilization and phytoavailability depending on the type of element and amendment. Therefore, we aimed to assess the impact of the application (1%) of several low cost amendments and environmental wastes on the (im)mobilization, availability, and uptake of Al, Cd, Cr, Cu, Fe, Mn, Ni, and Zn by sorghum (Sorghum bicolor) in a long term sewage effluent irrigated sandy soils collected from Egypt. The used materials include activated charcoal (AC), potassium humate (KH), phosphate rock (PR), phosphogypsum (PG), triple superphosphate (TSP), phosphoric acid (PA), sulfur (S), sugar beet factory lime (SBFL), cement bypass kiln dust (CBD), egg shell (ES), bone mill (BM), brick factory residual (BFR), ceramic powder (CP), and drinking water treatment residual (WTR). The mobilization and availability of the elements in the soil were extracted using NH 4 NO 3 and ammonium bicarbonate- diethylene triamine penta acetic acid (AB-DTPA), respectively. The above-ground biomass samples were analyzed for the elements studied. The results confirmed our hypothesis and concluded that although some amendments like S, PA, and TSP can be used for reducing the plant uptake of Al, Cr, and Fe, they might be used with KH for enhancing the phytoextraction of Cd, Cu, Mn, and Ni. Moreover, several wastes such as BFR and WTR might be used for enhancing the phytoextraction of Al, Cd, Cr, Cu, Fe, and Ni and reducing the uptake of Mn from the studied soil. Although SBFL decreased the plant uptake of Al, Fe, Mn, and Zn, it's increased the plant uptake of Cd, Cu, and Ni. Therefore, the amendments which reduce the plant uptake of an element might be suitable candidates for its immobilization, while the amendments which increase the plant uptake of

  3. Differences in soil solution chemistry between soils amended with nanosized CuO or Cu reference materials: implications for nanotoxicity tests.

    PubMed

    McShane, Heather V A; Sunahara, Geoffrey I; Whalen, Joann K; Hendershot, William H

    2014-07-15

    Soil toxicity tests for metal oxide nanoparticles often include micrometer-sized oxide and metal salt treatments to distinguish between toxicity from nanometer-sized particles, non-nanometer-sized particles, and dissolved ions. Test result will be confounded if each chemical form has different effects on soil solution chemistry. We report on changes in soil solution chemistry over 56 days-the duration of some standard soil toxicity tests-in three soils amended with 500 mg/kg Cu as nanometer-sized CuO (nano), micrometer-sized CuO (micrometer), or Cu(NO3)2 (salt). In the CuO-amended soils, the log Cu2+ activity was initially low (minimum -9.48) and increased with time (maximum -5.20), whereas in the salt-amended soils it was initially high (maximum -4.80) and decreased with time (minimum -6.10). The Cu2+ activity in the nano-amended soils was higher than in the micrometer-amended soils for at least the first 11 days, and lower than in the salt-amended soils for at least 28 d. The pH, and dissolved Ca and Mg concentrations in the CuO-amended soils were similar, but the salt-amended soils had lower pH for at least 14 d, and higher Ca and Mg concentrations throughout the test. Soil pretreatments such as leaching and aging prior to toxicity tests are suggested.

  4. Biochar amendment decreases soil microbial biomass and increases bacterial diversity in Moso bamboo (Phyllostachys edulis) plantations under simulated nitrogen deposition

    NASA Astrophysics Data System (ADS)

    Li, Quan; Lei, Zhaofeng; Song, Xinzhang; Zhang, Zhiting; Ying, Yeqing; Peng, Changhui

    2018-04-01

    Biochar amendment has been proposed as a strategy to improve acidic soils after overuse of nitrogen fertilizers. However, little is known of the role of biochar in soil microbial biomass carbon (MBC) and bacterial community structure and diversity after soil acidification induced by nitrogen (N) deposition. Using high-throughput sequencing of the 16S rRNA gene, we determined the effects of biochar amendment (BC0, 0 t bamboo biochar ha‑1 BC20, 20 t bamboo biochar ha‑1 and BC40, 40 t bamboo biochar ha‑1) on the soil bacterial community structure and diversity in Moso bamboo plantations that had received simulated N deposition (N30, 30 kg N ha‑1 yr‑1 N60, 60 kg N ha‑1 yr‑1 N90, 90 kg N ha‑1 yr‑1 and N-free) for 21 months. After treatment of N-free plots, BC20 significantly increased soil MBC and bacterial diversity, while BC40 significantly decreased soil MBC but increased bacterial diversity. When used to amend N30 and N60 plots, biochar significantly decreased soil MBC and the reducing effect increased with biochar amendment amount. However, these significant effects were not observed in N90 plots. Under N deposition, biochar amendment largely increased soil bacterial diversity, and these effects depended on the rates of N deposition and biochar amendment. Soil bacterial diversity was significantly related to the soil C/N ratio, pH, and soil organic carbon content. These findings suggest an optimal approach for using biochar to offset the effects of N deposition in plantation soils and provide a new perspective for understanding the potential role of biochar amendments in plantation soil.

  5. Rhizosphere Environment and Labile Phosphorus Release from Organic Waste-Amended Soils.

    NASA Astrophysics Data System (ADS)

    Dao, Thanh H.

    2015-04-01

    Crop residues and biofertilizers are primary sources of nutrients for organic crop production. However, soils treated with large amounts of nutrient-enriched manure have elevated phosphorus (P) levels in regions of intensive animal agriculture. Surpluses occurred in these amended soils, resulting in large pools of exchangeable inorganic P (Pi) and enzyme-labile organic P (Po) that averaging 30.9 and 68.2 mg kg-1, respectively. Organic acids produced during crop residue decomposition can promote the complexation of counter-ions and decouple and release unbound Pi from metal and alkali metal phosphates. Animal manure and cover crop residues also contain large amounts of soluble organic matter, and likely generate similar ligands. However, a high degree of heterogeneity in P spatial distribution in such amended fields, arising from variances in substrate physical forms ranging from slurries to dried solids, composition, and diverse application methods and equipment. Distinct clusters of Pi and Po were observed, where accumulation of the latter forms was associated with high soil microbial biomass C and reduced phosphomonoesterases' activity. Accurate estimates of plant requirements and lability of soil P pools, and real-time plant and soil P sensing systems are critical considerations to optimally manage manure-derived nutrients in crop production systems. An in situ X-ray fluorescence-based approach to sensing canopy and soil XRFS-P was developed to improve the yield-soil P relationship for optimal nutrient recommendations in addition to allowing in-the-field verification of foliar P status.

  6. Designing relevant biochars as soil amendments using lignocellulosic-based and manure-based feedstocks

    EPA Science Inventory

    Purpose: Biochars are a soil amendment produced from lignocellulosic and manure feedstocks. Not all biochars are viable soil amendments because of differences in their physical and chemical properties. Biochar could deliver more effective service as a soil amendment if its chemis...

  7. Lead Speciation and In Vitro Bioaccessibility of Compost-Amended Urban Garden Soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Attanayake, Chammi P.; Hettiarachchi, Ganga M.; Ma, Qing

    In situ soil amendments can modify the Pb bioavailability by changing soil Pb speciation. Urban soils from three vegetable gardens containing different total Pb concentrations were used. The study evaluated how compost amendment and aging of soil-compost mixture in situ affected the following: (i) soil Pb speciation in the field and (ii) change of soil Pb speciation during an in vitro bioaccessibility extraction mimicking gastric phase dissolution at pH 2.5. X-ray absorption fine structure spectroscopy was used to determine Pb speciation in amended and nonamended soils and residues left after in vitro bioaccessibility extraction of those soils. Compost amendment andmore » aging of compost in the field had a negligible effect on Pb bioaccessibility in the soils. Major Pb species in the soils were Pb sorbed to Fe oxy(hydr)oxide (Pb-Fh) and to soil organic C (Pb-Org). The fraction of Pb-Org was increased as soil-compost mixture aged in the field. During the in vitro extraction, the fraction of Pb-Fh was decreased, the fraction of Pb-Org was increased, and hydroxypyromorphite was formed in both amended and nonamended soils. Freshly incorporated compost enhanced the dissolution of Pb-Fh during the extraction. As soil-compost mixture aged in the field, the dissolution of Pb-Fh was low, demonstrating more stability of the Pb-Fh during the extraction. Compost amendment showed potential to contribute to reduced bioaccessibility of Pb as compost aged in the soil by increasing Pb-Org fraction in the field and stability of Pb-Fh during the in vitro bioaccessibility extraction.« less

  8. Evaluation of emission of greenhouse gases from soils amended with sewage sludge.

    PubMed

    Paramasivam, S; Fortenberry, Gamola Z; Julius, Afolabi; Sajwan, Kenneth S; Alva, A K

    2008-02-01

    Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate

  9. Critical evaluation of the use of the hydroxyapatite as a stabilizing agent to reduce the mobility of Zn and Ni in sewage sludge amended soils.

    PubMed

    Zupancic, Marija; Bukovec, Peter; Milacic, Radmila; Scancar, Janez

    2006-01-01

    The leachability of zinc (Zn) and nickel (Ni) was investigated in various soil types amended with sewage sludge and sewage sludge treated with hydroxyapatite. Sandy, clay and peat soils were investigated. For leachability tests, plastic columns (diameter 9 cm, height 50 cm) were filled with moist samples up to a height of 25 cm. Sewage sludge (1 kg) was mixed with 4.6 kg of clay and sandy soils and with 6.7 kg of peat soil. For sewage sludge mixtures treated with hydroxyapatite, 0.5 kg of the hydroxyapatite was added to 1 kg of the sewage sludge. Neutral (pH 7) and acid precipitation (pH 3.5) were applied. Acid precipitation was prepared from concentrated HNO(3), H(2)SO(4) and fresh doubly distilled water. The amount of precipitation corresponded to the average annual precipitation for the city of Ljubljana, Slovenia. It was divided into eight equal portions and applied sequentially on the top of the columns. The results indicated that the leachabilities of Zn in sewage sludge amended peat and clay soils were low (below 0.3% of total Zn content) and of Ni in sewage sludge amended sandy, clay and peat soil below 1.9% of total Ni content. In sewage sludge amended sandy soil, the leachability of Zn was higher (11% of Zn content). The pH of precipitation had no influence on the leachability of either metal. Treatment of sewage sludge with hydroxyapatite efficiently reduced the leachability of Zn in sewage sludge amended sandy soil (from 11% to 0.2% of total Zn content). In clay and peat sewage sludge amended soils, soil characteristics rather than hydroxyapatite treatment dominate Zn mobility.

  10. Application of MCPA herbicide on soils amended with biostimulants: short-time effects on soil biological properties.

    PubMed

    Tejada, Manuel; García-Martínez, Ana M; Gómez, Isidoro; Parrado, Juan

    2010-08-01

    In this paper we studied in the laboratory the effect of MCPA herbicide at a rate of 1.5lha(-1) (manufactures rate recommended) on biological properties of a Plagic Antrosol amended with four biostimulants (WCDS, wheat condensed distillers soluble; PA-HE, hydrolyzed poultry feathers; CGHE, carob germ enzymatic extract; and RB, rice bran extract). Seven hundred grams of soil were mixed with WCDS at a rate of 10%, CGHE at a rate of 4.7%, PA-HE at a rate of 4.3%, and RB at a rate of 4.4%, respectively, in order to applying the same amount of organic matter to the soil (16.38 g organic matter). An unamended polluted and amended non-polluted soil were used as control. For all treatments, the soil ergosterol, dehydrogenase, urease, and phosphatase activities were measured at two incubation times (0 and 60 d). The 16S rDNA-DGGE profiles in all treatments were determined at the beginning and end of the incubation period. The results indicated that at the end of the incubation period and compared with the control soil, the dehydrogenase, urease and phosphatase activities and ergosterol decreased 39.3%, 20%, 15.7% and 56.5%, respectively in the non-organic amended polluted soil. The application of organic matter to unpolluted soil increased the enzymatic activities and ergosterol. However, this stimulation was higher in the soil amended with RB, followed by PA-HE, WCDS and CGHE. The application of herbicide in organic-amended soils decreased the enzymatic activities and ergosterol content. However, this decrease was lower than for the non-amended herbicide polluted soil. Possibly the low molecular weight protein content easily assimilated by soil microorganisms and the adsorption capacity of humic substances are responsible for less inhibition of these enzyme activities and soil ergosterol. The 16S rDNA-DGGE profiles indicated that herbicide did not negatively affect soil bacterial biodiversity. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  11. Global Warming Potential from early phase decomposition of soil organic matter amendments

    NASA Astrophysics Data System (ADS)

    Mayer, A.; Silver, W. L.

    2015-12-01

    Organic matter amendments to soil are widely used as a method of enhancing nutrient availability for crops or grassland. Amendments such as composted manure or greenwaste also have the co-benefits of potentially increasing soil carbon (C) stocks (DeLonge et al., 2013) and diverting organic waste from landfills or manure lagoons. However, application of organic matter amendments can also stimulate emissions of greenhouse gases (GHGs). In this study we determined how the chemical quality of organic matter amendments affected soil C and N content and GHG emissions during early stage decomposition. California grassland soils were amended with six different amendments of varying C and N content including three composts and three feedstocks (goat and horse bedding and cattle manure). Amendments and soils were incubated in the laboratory for 7 weeks; GHG fluxes were measured weekly. The three feedstocks emitted significantly more GHGs than the composted materials. With the exception of cow manure, N content of the amendment was linearly correlated with global warming potential emitted (R2= 0.66, P <0.0001). C:N ratios were not a significant predictor of GHG emissions. Cow manure stimulated a net loss of C (or C equivalents) in the mineral soil, as expected. However, greenwaste compost also surprisingly resulted in net C losses, while goat bedding, horse bedding, and the other compost were either C neutral or a slight net C sink at the end of the incubation. Ongoing analyses are examining the fate of the C incorporated from the amendment to the soil as occluded or free light fraction, as well as N mineralization rates. Our data suggest that N content of organic matter amendments is a good predictor of initial GHG emissions. The study also indicates that composting greenwaste with N-rich bedding and manure can result in lower GHG emissions and C sequestration compared to the individual uncomposted components.

  12. Biodegradation of Used Motor Oil in Soil Using Organic Waste Amendments

    PubMed Central

    Abioye, O. P.; Agamuthu, P.; Abdul Aziz, A. R.

    2012-01-01

    Soil and surface water contamination by used lubricating oil is a common occurrence in most developing countries. This has been shown to have harmful effects on the environment and human beings at large. Bioremediation can be an alternative green technology for remediation of such hydrocarbon-contaminated soil. Bioremediation of soil contaminated with 5% and 15% (w/w) used lubricating oil and amended with 10% brewery spent grain (BSG), banana skin (BS), and spent mushroom compost (SMC) was studied for a period of 84 days, under laboratory condition. At the end of 84 days, the highest percentage of oil biodegradation (92%) was recorded in soil contaminated with 5% used lubricating oil and amended with BSG, while only 55% of oil biodegradation was recorded in soil contaminated with 15% used lubricating oil and amended with BSG. Results of first-order kinetic model to determine the rate of biodegradation of used lubricating oil revealed that soil amended with BSG recorded the highest rate of oil biodegradation (0.4361 day−1) in 5% oil pollution, while BS amended soil recorded the highest rate of oil biodegradation (0.0556 day−1) in 15% oil pollution. The results of this study demonstrated the potential of BSG as a good substrate for enhanced remediation of hydrocarbon contaminated soil at low pollution concentration. PMID:22919502

  13. In situ stabilization of cadmium-, lead-, and zinc-contaminated soil using various amendments.

    PubMed

    Lee, Sang-Hwan; Lee, Jin-Soo; Choi, Youn Jeong; Kim, Jeong-Gyu

    2009-11-01

    Chemical stabilization is an in situ remediation method that uses inexpensive amendments to reduce contaminant availability in polluted soil. We tested the effects of several amendments (limestone, red-mud, and furnace slag) on the extractability of heavy metals, microbial activities, phytoavailability of soil metals (assessed using lettuce, Lactuca sativa L.), and availability of heavy metals in ingested soil to the human gastrointestinal system (assessed using the physiologically based extraction test). The application of soil amendments significantly decreased the amount of soluble and extractable heavy metals in the soil (p<0.05). The decreased extractable metal content of soil was accompanied by increased microbial activity and decreased plant uptake of heavy metals. Soil microbial activities (soil respiration, urease, and dehydrogenase activity) significantly increased in limestone and red-mud-amended soils. Red-mud was the most effective treatment in decreasing heavy-metal concentrations in lettuce. Compared to non-amended control soil, lettuce uptake of Cd, Pb, and Zn was reduced 86%, 58%, and 73%, respectively, by the addition of red-mud.

  14. Sorbent amendment as a remediation strategy to reduce PFAS mobility and leaching in a contaminated sandy soil from a Norwegian firefighting training facility.

    PubMed

    Hale, Sarah E; Arp, Hans Peter H; Slinde, Gøril Aasen; Wade, Emma Jane; Bjørseth, Kamilla; Breedveld, Gijs D; Straith, Bengt Fredrik; Moe, Kamilla Grotthing; Jartun, Morten; Høisæter, Åse

    2017-03-01

    Aqueous film-forming foams (AFFF) containing poly- and perfluoroalkyl substances (PFAS) used for firefighting have led to the contamination of soil and water at training sites. The unique physicochemical properties of PFAS results in environmental persistency, threatening water quality and making remediation of such sites a necessity. This work investigated the role of sorbent amendment to PFAS contaminated soils in order to immobilise PFAS and reduce mobility and leaching to groundwater. Soil was sampled from a firefighting training facility at a Norwegian airport and total and leachable PFAS concentrations were quantified. Perfluorooctanesulfonic acid (PFOS) was the most dominant PFAS present in all soil samples (between 9 and 2600 μg/kg). Leaching was quantified using a one-step batch test with water (L/S 10). PFOS concentrations measured in leachate water ranged between 1.2 μg/L and 212 μg/L. Sorbent amendment (3%) was tested by adding activated carbon (AC), compost soil and montmorillonite to selected soils. The extent of immobilisation was quantified by measuring PFAS concentrations in leachate before and after amendment. Leaching was reduced between 94 and 99.9% for AC, between 29 and 34% for compost soil and between 28 and 40% for the montmorillonite amended samples. Sorbent + soil/water partitioning coefficients (K D ) were estimated following amendment and were around 8 L/kg for compost soil and montmorillonite amended soil and ranged from 1960 to 16,940 L/kg for AC amended soil. The remediation of AFFF impacted soil via immobilisation of PFAS following sorbent amendment with AC is promising as part of an overall remediation strategy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Crop response to localized organic amendment in soils with limiting physical properties

    NASA Astrophysics Data System (ADS)

    Lordan, Joan; Pascual, Miquel; Fonseca, Francisco; Villar, Josep Maria; Montilla, Victor; Papió, Josep; Rufat, Josep

    2013-04-01

    This 2-year study evaluated the use of rice husk as a localized organic amendment in a soil with limiting physical properties. The research was conducted in a commercial peach orchard planted in 2011 using a ridge planting system. Six soil and water management treatments were evaluated in 18 experimental units, which were set up in the field using a randomized complete block design. The treatments were compared both in terms of soil physical properties and crop response. Soil amendment with rice husk was the most effective technique. It improved soil conditions (soil infiltration and soil porosity), providing a better soil environment for root activity and thereby resulted in better crop performance. Concerning growth parameters, the amended treatment presented the highest overall values without negatively affecting crop water status. These techniques were suitable for mitigating the effects of soils with limiting physical conditions. Localized applications of amendments, as proposed in this work, imply an important reduction in application rates. It is important to consider an efficient use of by-products since there is a growing interest in industrial and agronomical exploitations.

  16. Fate and effect of imidacloprid on vermicompost-amended soils under dissimilar conditions: Risk for soil functions, structure, and bacterial abundance.

    PubMed

    Castillo Diaz, Jean Manuel; Martin-Laurent, Fabrice; Beguet, Jérèmie; Nogales, Rogelio; Romero, Esperanza

    2017-02-01

    The fate and impact of pesticide on soil depend partly on the agricultural practices, such as prior treatment with pesticide and/or organic amendments. As a means of determining how the previous soil conditions can affect the fate of imidacloprid (IMI) and its effect on soil functions, experiments were made with soil samples, double-amended or not with either vine-shoot (W) or olive cake (O) vermicompost or contaminated or not with IMI. These soil samples, incubated for 3months, were placed in two microcosms (M1 with the pre-amended soils and M2 with the pre-exposed soils), treated with IMI and amended with vermicomposts and then incubated for 3months. The IMI distribution on soil fractions, sorption processes, dissipation kinetics, and biochemical as well as genetic structure and bacterial abundance were determined to assess the fate and impact of IMI on the soil. The addition of W vermicompost to the soil reduced the IMI availability. The dissipation kinetic in soils from M1 and M2 followed, respectively, a single first-order and a double first-order in parallel models. The lowest IMI persistence corresponded to the soil from M2 amended with O-vermicompost with DT50 and DT90 values of 67d and 265d, while in the other soils 90% dissipation required >512d. The vermicomposts-amended contaminated soils increased the dehydrogenase activity by 2- and 4-fold respect the control soils. However, the urease activity decreased due to the IMI influence. The changes in the bacterial community in the contaminated soil amended with O-vermicompost during incubation were correlated with the dissipation rate constant of IMI, suggesting a better tolerance of microorganisms to IMI. Thus, in the soil contaminated with IMI, the amendment with the vermicompost from olive cake can mitigate the impact of this insecticide on soil functions and promote its depuration capability while minimizing environmental risks. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Soil biota response to amendment with biochar as P and K fertilizer

    NASA Astrophysics Data System (ADS)

    Winding, Anne; Imparato, Valentina; Santos, Susana; Hansen, Veronika; Haugaard-Nielsen, Henrik; Browne, Patrick; Hestbjerg Hansen, Lars; Henning Krogh, Paul; Johansen, Anders

    2017-04-01

    Thermal gasification converts biomass into a combustible gas at oxygen-poor conditions, the bi-product being biochar which can be used as soil amendment to increase pH, sequester carbon to mitigate climate change, and supply phosphate and potassium to crops; replacing chemical or other alternative organic fertilizers. Amending soil with biochar can support three soil functions: production of food, carbon sequestration, and biodiversity. This was tested in a field experiment with reduced-tillage agricultural management, where the effect of biochar amendment on soil ecosystem services, especially biodiversity and carbon sequestration were studied. The effects on soil microorganisms and fauna (protists and earthworms) were assessed with activity based assays and Next Generation Sequencing (NGS). Crops were alternating oil seed rape and winter wheat, and biochar was added annually for 3 years. The soil was a sandy loam soil with SOM content of ca. 5%. Earthworms and soil were sampled from field plots either left untreated, amended with straw or annually amended with either 6-8 t ha-1 or ca. 1 t ha-1 biochar. Soil was sampled from bulk soil and earthworm drilosphere. Earthworms had a priming effect on protist abundance and basal soil respiration. However, in biochar amended soil the protist abundance decreased in the drilosphere. Culturable bacteria and extracellular enzymatic activities were not significantly affected by earthworms. The abundance of only one earthworm species increased at high compared to low application levels of biochar, while still not differing from controls without biochar. Thus, no harmful effects were detected for earthworms. At the lower biochar amendment, significant changes were observed for the activity of a few selected enzymes related to biochar and also a relative increase in abundance of low abundant microorganisms was seen. At the high doses of biochar the abundance of protists increased compared to control. NGS analysis was more

  18. Populations of Pratylenchus penetrans Relative to Decomposing Nitrogenous Soil Amendments

    PubMed Central

    Walker, J. T.

    1971-01-01

    Populations of Pratylenchus penetrans decreased in soil following addition of 70 and 700 ppm N in the form of nitrate, nitrite, organic nitrogen, or ammonium compounds. Nitrate was less effective than other nitrogen carriers. Population reduction is principally attributed to ammonification during decomposition. This hypothesis is supported by chromatographic analyses of soil atmospheres, survival of nematodes in pure CO₂ and N₂, inverse relationship of CO₂, content in amended soils to nematode populations, and direct relationship of NH₃-N content of amended soils to nematode populations. PMID:19322339

  19. Uptake of aromatic arsenicals from soil contaminated with diphenylarsinic acid by rice.

    PubMed

    Arao, Tomohito; Maejima, Yuji; Baba, Koji

    2009-02-15

    Chemical warfare agents containing aromatic arsenicals (AAs) such as Clark I (diphenylchloroarsine) are well-known, as is the risk of leakage from such munitions into the environment. We investigated the uptake of AAs in agricultural soils by rice. Methylphenylarsinic acid (MPAA) was detected in brown rice grown in contaminated soil. Dimethylphenylarsine oxide (DMPAO) and methyldiphenylarsine oxide (MDPAO) were detected in the straw but not in the grains grown in the contaminated soil. Inthe contaminated soil, phenylarsonic acid (PAA) and MPAA concentrations decreased and DMPAO concentration increased under the flooded conditions; however, their concentrations remained unchanged underthe upland conditions. DMPAO was detected in the straw of the rice grown in PAA- or MPAA-amended soil but was not detected in that grown in a PAA- or MPAA-added solution culture. MDPAO was detected in the straw of the rice grown in diphenylarsinic acid (DPAA)-amended soil but was not detected in that grown in a DPAA-added solution culture. Thus, MPAA and DPAA were methylated not in the rice plant but in the soil under the flooded conditions. Dephenylated products were detected in the straw grown in AA-added solution cultures, but demethylated products were not detected. DMPAO and MDPAO absorbed by the shoots were retained, and MPAA and DPAA absorbed by the shoots were translocated to the grains more easily than other AAs.

  20. Seasonal and soil-type dependent emissions of nitrous oxide from irrigated desert soils amended with digested poultry manures.

    PubMed

    Posmanik, Roy; Nejidat, Ali; Dahan, Ofer; Gross, Amit

    2017-09-01

    Expansion of dryland agriculture requires intensive supplement of organic fertilizers to improve the fertility of nutrient-poor desert soils. The environmental impact of organic supplements in hot desert climates is not well understood. We report on seasonal emissions of nitrous oxide (N 2 O) from sand and loess soils, amended with limed and non-limed anaerobic digestate of poultry manure in the Israeli Negev desert. All amended soils had substantially higher N 2 O emissions, particularly during winter applications, compared to unammended soils. Winter emissions from amended loess (10-175mgN 2 Om -2 day -1 ) were markedly higher than winter emissions from amended sand (2-7mgN 2 Om -2 day -1 ). Enumeration of marker genes for nitrification and denitrification suggested that both have contributed to N 2 O emissions according to prevailing environmental conditions. Lime treatment of digested manure inhibited N 2 O emissions regardless of season or soil type, thus reducing the environmental impact of amending desert soils with manure digestate. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Amending Jasper County, Missouri soils with biochar and ...

    EPA Pesticide Factsheets

    Abandoned mines and the residuals from mining across the U.S. pose a considerable, pervasive risk to human health and the environment. Many soils in the Tri-State-Mining District (TSMD), located where Missouri, Kansas and Oklahoma meet, have been affected by the residuals of historic lead and zinc mining. Here we describe a research collaboration between ORD and Region 7 to investigate the use of customized soil amendments, which will include biochar, as a tool to provide both soil remediation and reestablishment of a soil-stabilizing native plant community at sites in the TSMD. Biochar is a charcoal-like, carbon-rich, porous by-product of thermal pyrolysis or gasification. A benefit of using biochar is the ability to engineer its properties to correspond to specific soil remediation needs. Specifically, it has properties that make it well suited for use in remediating mine soils and reestablishing vegetation, with studies indicating that biochar can complex and immobilize heavy metals. This is of critical importance for mining influenced sites. However, the optimized biochar properties for the remediation of acidic mine soils are not yet fully known. Biochar can be produced to have a range of pH values, depending upon feedstock and pyrolysis or gasification conditions, and post-production activation. Therefore, this material may be used as a liming agent to raise soil pH. Additionally, some biochars have been shown to improve soil water holding capacities and

  2. Kinetic characteristic of phenanthrene sorption in aged soil amended with biochar

    NASA Astrophysics Data System (ADS)

    Kim, Chanyang; Kim, Yong-Seong; Hyun, Seunghun

    2015-04-01

    Biochar has been recently highlighted as an amendment that affects yield of the crops by increasing pH, cation exchange capacity and water retention, and reduces the lability of contaminants by increasing sorption capacity in the soil system. Biochar's physico-chemical properties, high CEC, surfaces containing abundant micropores and macropores, and various types of functional groups, play important roles in enhancing sorption capacity of contaminants. Aging through a natural weathering process might change physico-chemical properties of biochar amended in soils, which can affect the sorption behavior of contaminants. Thus, in this study, the sorption characteristics of phenanthrene (PHE) on biochar-amended soils were studied with various types of chars depending on aging time. To do this, 1) soil was amended with sludge waste char (SWC), wood char (WC), and municipal waste char (MWC) during 0, 6, and 12 month. Chars were applied to soil at 1% and 2.5% (w/w) ratio. 2) Several batch kinetic and equilibrium studies were conducted. One-compartment first order and two-compartment first order model apportioning the fraction of fast and slow sorbing were selected for kinetic models. Where, qt is PHE concentration in biochar-amended soils at each time t, qeis PHE concentration in biochar-amended soils at equilibrium. ff is fastly sorbing fraction and (1-ff) is slowly sorbing fraction. k is sorption rate constant from one-compartment first order model, k1 and k2 are sorption rate constant from two-compartment first order model, t is time (hr). The equilibrium sorption data were fitted with Fruendlich and Langmuir equation. 3) Change in physico-chemical properties of biochar-amended soils was investigated with aging time. Batch equilibrium sorption results suggested that sorbed amount of PHE on WC was greater than SWC and MWC. The more char contents added to soil, the greater sorption capacity of PHE. Sorption equilibrium was reached after 4 hours and equilibrium pH ranged

  3. Biomass ashes from pyrolytic wood liquefaction as novel soil amendments

    NASA Astrophysics Data System (ADS)

    Fernández-Delgado Juárez, Marina; Gómez Brandón, María; Mazzier, Thomas; Schönegger, Deborah; Hermanns, Roy; Leijenhorst, Evert; Insam, Heribert

    2017-04-01

    What happens when an old soil amendment is in fact a new one? Traditionally, ashes from biomass combustion were considered as a valuable resource, and widely used as an agricultural soil amendment. However, in recent decades we have been reluctant to apply them to soils, despite the increase in the production of combustion ashes resulting from the development of new fuels derived from biomass residues. The production of Fast Pyrolysis Bio Oil (FPBO) out of various lignocellulosic biomass streams is one of the newest technologies for gaining a liquid biofuel that can be seen as a future substitute for mineral oils. During the pyrolysis process, the by-products (charcoal and low calorific gases) are combusted to generate energy, resulting in the production of ashes that contain the majority of the minerals and salts originally present in the feedstock. The main objective of the present work is to investigate if the recovered ashes from the pyrolysis process can be used as a soil amendment. A greenhouse trial was set up in order to evaluate the impact of the ashes on an acid grassland soil (eutric Cambisol) from the region of Tyrol (Austria). A two-level experimental design (ash treatment, and plant effect) was set up. The ashes were mixed with the soil columns at a ratio of 1% (w:w, fresh weight). A control treatment that consisted of soil without the addition of ashes was also included. Moreover, to understand the effect that the ashes would have on crop growth, ten seeds of a traditional wheat variety (Tiroler Früher Dinkel; Triticum aestivum subsp. spelta), were placed in half of the columns with and without ashes, so as to determine the seed germination index and plant growth. Moreover, specific microbial groups related to N cycle were quantified by real-time PCR. A total of 24 experimental units (2 ash treatments x 2 incubation times x 2 plant levels x 3 replicates) were analysed. After an equilibration period of 24 h at 4 °C (referred as time zero), the

  4. Environmental fate of roxarsone in poultry litter. Part II. Mobility of arsenic in soils amended with poultry litter

    USGS Publications Warehouse

    Rutherford, D.W.; Bednar, A.J.; Garbarino, J.R.; Needham, R.; Staver, K.W.; Wershaw, R. L.

    2003-01-01

    Poultry litter often contains arsenic as a result of organo-arsenical feed additives. When the poultry litter is applied to agricultural fields, the arsenic is released to the environment and may result in increased arsenic in surface and groundwater and increased uptake by plants. The release of arsenic from poultry litter, litter-amended soils, and soils without litter amendment was examined by extraction with water and strong acids (HCI and HN03). The extracts were analyzed for As, C, P, Cu, Zn, and Fe. Copper, zinc, and iron are also poultry feed additives. Soils with a known history of litter application and controlled application rate of arsenic-containing poultry litter were obtained from the University of Maryland Agricultural Experiment Station. Soils from fields with long-term application of poultry litter were obtained from a tilled field on the Delmarva Peninsula (MD) and an untilled Oklahoma pasture. Samples from an adjacent forest or nearby pasture that had no history of litter application were used as controls. Depth profiles were sampled for the Oklahoma pasture soils. Analysis of the poultry litter showed that 75% of the arsenic was readily soluble in water. Extraction of soils shows that weakly bound arsenic mobilized by water correlates positively with C, P, Cu, and Zn in amended fields and appears to come primarily from the litter. Strongly bound arsenic correlates positively with Fe in amended fields and suggests sorption or coprecipitation of As and Fe in the soil column.

  5. Metolachlor Sorption and Degradation in Soil Amended with Fresh and Aged Biochars.

    PubMed

    Trigo, Carmen; Spokas, Kurt A; Hall, Kathleen E; Cox, Lucia; Koskinen, William C

    2016-04-27

    Addition of organic amendments such as biochar to soils can influence pesticide sorption-desorption processes and, in turn, the amount of pesticide readily availability for transport and biodegradation. Sorption-desorption processes are affected by both the physical and chemical properties of soils and pesticides, as well as soil-pesticide contact time, or aging. Changes in sorption-desorption of metolachlor with aging in soil amended with three macadamia nut shell biochars aged 0 (BCmac-fr), 1 year (BCmac-1yr), and 2 years (BCmac-2yr) and two wood biochars aged 0 (BCwood-fr) and 5 years (BCwood-5yr) were determined. Apparent sorption coefficient (Kd-app) values increased with incubation time to a greater extent in amended soil as compared to unamended soils; Kd-app increased by 1.2-fold for the unamended soil, 2.0-fold for BCwood-fr, 1.4-fold for BCwood-5yr, 2.4-fold for BCmac-fr, 2.5-fold for BCmac-1yr, and 1.9-fold for BCmac-4yr. The increase in calculated Kd-app value was the result of a 15% decrease in the metolachlor solution concentration extractable with CaCl2 solution with incubation time in soil as compared to a 50% decrease in amended soil with very little change in the sorbed concentration. Differences could possibly be due to diffusion to less accessible or stronger binding sites with time, a faster rate of degradation (in solution and on labile sites) than desorption, or a combination of the two in the amended soils. These data show that transport models would overpredict the depth of movement of metolachlor in soil if effects of aging or biochar amendments are not considered.

  6. Enzyme Sorption onto Soil and Biocarbon Amendments Alters Catalytic Capacity and Depends on the Specific Protein and pH

    NASA Astrophysics Data System (ADS)

    Foster, E.; Fogle, E. J.; Cotrufo, M. F.

    2017-12-01

    Enzymes catalyze biogeochemical reactions in soils and play a key role in nutrient cycling in agricultural systems. Often, to increase soil nutrients, agricultural managers add organic amendments and have recently experimented with charcoal-like biocarbon products. These amendments can enhance soil water and nutrient holding capacity through increasing porosity. However, the large surface area of the biocarbon has the potential to sorb nutrients and other organic molecules. Does the biocarbon decrease nutrient cycling through sorption of enzymes? In a laboratory setting, we compared the interaction of two purified enzymes β-glucosidase and acid phosphatase with a sandy clay loam and two biocarbons. We quantified the sorbed enzymes at three different pHs using a Bradford protein assay and then measured the activity of the sorbed enzyme via high-throughput fluorometric analysis. Both sorption and activity depended upon the solid phase, pH, and specific enzyme. Overall the high surface area biocarbon impacted the catalytic capacity of the enzymes more than the loam soil, which may have implications for soil nutrient management with these organic amendments.

  7. [Impact of biochar amendment on the sorption and dissipation of chlorantraniliprole in soils].

    PubMed

    Wang, Ting-Ting; Yu, Xiang-Yang; Shen, Yaen; Zhang, Chao-Lan; Liu, Xian-Jin

    2012-04-01

    The effects of biochar amendment on sorption and dissipation of chlorantraniliprole (CAP) in 5 different agricultural soils were studied. Red gum wood (Eucalyptus spp.) derived biochar was amended into a black soil, a yellow soil, a red soil, a purplish soil, and a fluvo-aquic soil at the rate of 0.5% (by weight). The sorption and dissipation behaviors of CAP in soils with and without biochar amendment were measured by batch equilibration technique and dissipation kinetic experiment, respectively. The objective was to investigate the impact of biochar application on the environmental fate of pesticides in agricultural soils with different physical-chemical properties, and evaluate the potential ecological impacts of field application of biochar materials. The results showed that biochar application in soils could enhance the sorption of CAP, but the magnitudes were varied among soils with different properties. Amendment of 0.5% (by weight) biochar in the black soil, which have high content of organic matter (4.59%), resulted in an increase of sorption coefficient (K(d)) by 2.17%; while for the fluvo-aquic soil with organic matter content of 1.16%, amendment of biochar at the same level led to an increase of 139.13%. The sorption capacity of biochar was partially suppressed when biochar was mixed with soils. The calculated K(Fbiochar) of biochar after mixed in the black soil, yellow soil, red soil, purplish soil, and fluvo-aquic soil were decreased by 96.94%, 90.6%, 91.31%, 68.26%, and 34.59%, respectively, compared to that of the original biochar. The half-lives of CAP in black soil, yellow soil, red soil, purplish soil, and fluvo-aquic soil were 115.52, 133.30, 154.03, 144.41 and 169.06 d, respectively. In soils amended with biochar, the corresponding half-lives of CAP were extended by 20.39, 35.76, 38.51, 79.19, and 119.75 d, respectively. Similar to the effects of biochar on CAP sorption, in soil with higher content of organic matter, the retardation of CAP

  8. Soil microbial properties after 5 years of consecutive amendment with composted tannery sludge.

    PubMed

    Araujo, Ademir Sérgio Ferreira; Miranda, Ana Roberta Lima; Oliveira, Mara Lucia Jacinto; Santos, Vilma Maria; Nunes, Luís Alfredo Pinheiro Leal; Melo, Wanderley José

    2015-01-01

    Composting has been recognised an alternative method to tannery sludge recycling and afterwards to be used in agriculture. As the tannery sludge contains salts and chromium, the application of composted tannery sludge (CTS) should be performed carefully to minimise negative effects on soil microbial properties. Therefore, this study evaluated the effects of 5-year repeated CTS amendment on soil microbial biomass (SMB) and enzyme activities in a tropical soil. CTS was applied during 5 years at 0, 2.5, 5, 10 and 20 Mg ha(-1), and at the fifth year, the microbial biomass C (MBC) and N (MBN), basal and substrate-induced respiration (SIR), metabolic quotient (qCO₂) and dehydrogenase (DHA) and fluorescein diacetate (FDA) hydrolysis were determined in the soil samples. Soil MBC and MBN showed the highest values with the amendment of 5 Mg ha(-1) CTS. Soil respiration increased with the increase in CTS rates, while SIR showed the highest values with the amendment of 0, 2.5 and 5 Mg ha(-1) CTS. DHA activity showed the highest values with the amendment up to 2.5 Mg ha(-1), while FDA hydrolysis increased up to the rate of 5 Mg ha(-1) CTS. The results show that after 5 years of permanent amendment of CTS, soils amended with 2.5 Mg ha(-1) have SMB and enzymatic activities similar to those in unamended soil.

  9. Effects of Biosolid Soil Amendment on Heterodera glycines Populations

    PubMed Central

    Melakeberhan, H; Noel, G. R.

    2006-01-01

    The high degree of parasitic variability in Heterodera glycines and its distribution in a wide range of soybean production systems present multiple challenges for management, which necessitate increased understanding of the biology of H. glycines. Soil amendments are being considered either as stand-alone and/or as part of integrated management approaches. A recycled municipal biosolid with nutrition supplement and liming qualities, N-Viro Soil (NVS) has potential as a multi-purpose soil amendment. In three greenhouse experiments, the effects of 0, 1.0 or 4.0 g NVS/100 cm3 of sandy loam soil on three H. glycines populations (GN1, GN2 and GN3) were investigated on soybean grown for 557 ± 68 degree-days (base 10°C). The response of the three H. glycines populations to NVS treatment varied by experiment. The overall numbers of preadult stages and cysts generally decreased with increasing levels of NVS in all experiments, and the high rate was more effective than the low rate in suppressing H. glycines numbers. This suggests that the high NVS treatment can affect the three populations in the experimental soil type under controlled conditions. Field studies to determine efficacy of the soil amendment in a wide range of environments should be initiated. PMID:19259540

  10. Soil characteristics of sediment-amended baldcypress (Taxodium distichum) swamps of coastal Louisiana

    USGS Publications Warehouse

    Jiang, Ming; Middleton, Beth A.

    2011-01-01

    Amendments of sediment from dredging activities have played an important role in raising the elevation of sinking coastal wetlands. This study compared the soil characteristics of sediment- amended coastal swamps in the Barataria Preserve unit of Jean Lafitte National Historical Park and Preserve with natural swamps along Bayou des Familles. The sandy sediment amendments used in the coastal forests had different soil texture and characteristics than the more organic soils of the natural swamps. Three years after the application of these sediments on the sediment-amended swamps, dewatering and compaction of the sediment had occurred but the sediment still had high salinity and bulk density, and low organic matter content. The two sediment-amended swamps differed from each other in that Site 1 had a higher elevation (mean = 25 cm higher) and drier soil than Site 2. The effects of sediment in coastal forested wetlands require separate consideration from studies of salt marshes, e.g., the weight of the sediment might damage tree roots, or the amendments might influence soil stability during storms in a different way. Generally, this study suggests that shallower depths of sediment are more likely to yield environments beneficial to these sinking baldcypress swamps in coastal Louisiana.

  11. A comparative study on the influence of different organic amendments on trace element mobility and microbial functionality of a polluted mine soil.

    PubMed

    Abad-Valle, P; Iglesias-Jiménez, E; Álvarez-Ayuso, E

    2017-03-01

    A mine soil heavily polluted with zinc and cadmium was employed to evaluate the capacity of organic amendments of different origin to simultaneously reduce soil trace element mobility and enhance soil microbial functionality. With this aim, four organic products, namely olive processing solid waste (OPSW), municipal solid waste compost (MSWC), leonardite and peat, were applied individually at different doses (0, 1, 2 and 5%) to mine soil under controlled laboratory conditions. Extraction studies and analysis of soil microbiological parameters (basal soil respiration and dehydrogenase, β-glucosidase, urease, arylsulfatase and acid and alkaline phosphatase activities) were performed to assess the effect of such amendments on soil restoration. Their ability to decrease mine soil mobile trace element contents followed the sequence MSWC > OPSW > peat > leonardite, with the former achieving reduction levels of 78 and 73% for Zn and Cd, respectively, when applied at a dose of 5%. This amendment also showed a good performance to restore soil microbial functionality. Thus, basal soil respiration and dehydrogenase, urease and alkaline phosphatase activities experienced increases of 187, 79, 42 and 26%, respectively, when mine soil was treated with 5% MSWC. Among tested organic products, MSWC proved to be the best amendment to perform both the chemical and the microbial soil remediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Sludge Biochar Amendment and Alfalfa Revegetation Improve Soil Physicochemical Properties and Increase Diversity of Soil Microbes in Soils from a Rare Earth Element Mining Wasteland

    PubMed Central

    Inubushi, Kazuyuki; Liang, Jian; Zhu, Sipin; Wei, Zhenya; Guo, Xiaobin; Luo, Xianping

    2018-01-01

    Long-term unregulated mining of ion-adsorption clays (IAC) in China has resulted in severe ecological destruction and created large areas of wasteland in dire need of rehabilitation. Soil amendment and revegetation are two important means of rehabilitation of IAC mining wasteland. In this study, we used sludge biochar prepared by pyrolysis of municipal sewage sludge as a soil ameliorant, selected alfalfa as a revegetation plant, and conducted pot trials in a climate-controlled chamber. We investigated the effects of alfalfa revegetation, sludge biochar amendment, and their combined amendment on soil physicochemical properties in soil from an IAC mining wasteland as well as the impact of sludge biochar on plant growth. At the same time, we also assessed the impacts of these amendments on the soil microbial community by means of the Illumina Miseq sequences method. Results showed that alfalfa revegetation and sludge biochar both improved soil physicochemical properties and microbial community structure. When alfalfa revegetation and sludge biochar amendment were combined, we detected additive effects on the improvement of soil physicochemical properties as well as increases in the richness and diversity of bacterial and fungal communities. Redundancy analyses suggested that alfalfa revegetation and sludge biochar amendment significantly affected soil microbial community structure. Critical environmental factors consisted of soil available K, pH, organic matter, carbon–nitrogen ratio, bulk density, and total porosity. Sludge biochar amendment significantly promoted the growth of alfalfa and changed its root morphology. Combining alfalfa the revegetation with sludge biochar amendment may serve to not only achieve the revegetation of IAC mining wasteland, but also address the challenge of municipal sludge disposal by making the waste profitable. PMID:29751652

  13. Sludge Biochar Amendment and Alfalfa Revegetation Improve Soil Physicochemical Properties and Increase Diversity of Soil Microbes in Soils from a Rare Earth Element Mining Wasteland.

    PubMed

    Luo, Caigui; Deng, Yangwu; Inubushi, Kazuyuki; Liang, Jian; Zhu, Sipin; Wei, Zhenya; Guo, Xiaobin; Luo, Xianping

    2018-05-11

    Long-term unregulated mining of ion-adsorption clays (IAC) in China has resulted in severe ecological destruction and created large areas of wasteland in dire need of rehabilitation. Soil amendment and revegetation are two important means of rehabilitation of IAC mining wasteland. In this study, we used sludge biochar prepared by pyrolysis of municipal sewage sludge as a soil ameliorant, selected alfalfa as a revegetation plant, and conducted pot trials in a climate-controlled chamber. We investigated the effects of alfalfa revegetation, sludge biochar amendment, and their combined amendment on soil physicochemical properties in soil from an IAC mining wasteland as well as the impact of sludge biochar on plant growth. At the same time, we also assessed the impacts of these amendments on the soil microbial community by means of the Illumina Miseq sequences method. Results showed that alfalfa revegetation and sludge biochar both improved soil physicochemical properties and microbial community structure. When alfalfa revegetation and sludge biochar amendment were combined, we detected additive effects on the improvement of soil physicochemical properties as well as increases in the richness and diversity of bacterial and fungal communities. Redundancy analyses suggested that alfalfa revegetation and sludge biochar amendment significantly affected soil microbial community structure. Critical environmental factors consisted of soil available K, pH, organic matter, carbon⁻nitrogen ratio, bulk density, and total porosity. Sludge biochar amendment significantly promoted the growth of alfalfa and changed its root morphology. Combining alfalfa the revegetation with sludge biochar amendment may serve to not only achieve the revegetation of IAC mining wasteland, but also address the challenge of municipal sludge disposal by making the waste profitable.

  14. Nitrogen Amendment Stimulated Decomposition of Maize Straw-Derived Biochar in a Sandy Loam Soil: A Short-Term Study.

    PubMed

    Lu, Weiwei; Ding, Weixin; Zhang, Junhua; Zhang, Huanjun; Luo, Jiafa; Bolan, Nanthi

    2015-01-01

    This study examined the effect of nitrogen (N) on biochar stability in relation to soil microbial community as well as biochar labile components using δ13C stable isotope technology. A sandy loam soil under a long-term rotation of C3 crops was amended with biochar produced from maize (a C4 plant) straw in absence (BC0) and presence (BCN) of N and monitored for dynamics of carbon dioxide (CO2) flux, phospholipid fatty acids (PLFAs) profile and dissolved organic carbon (DOC) content. N amendment significantly increased the decomposition of biochar during the first 5 days of incubation (P < 0.05), and the proportions of decomposed biochar carbon (C) were 2.30% and 3.28% in BC0 and BCN treatments, respectively, during 30 days of incubation. The magnitude of decomposed biochar C was significantly (P < 0.05) higher than DOC in biochar (1.75%) and part of relatively recalcitrant biochar C was mineralized in both treatments. N amendment increased soil PLFAs concentration at the beginning of incubation, indicating that microorganisms were N-limited in test soil. Furthermore, N amendment significantly (P < 0.05) increased the proportion of gram-positive (G+) bacteria and decreased that of fungi, while no noticeable changes were observed for gram-negative (G-) bacteria and actinobacteria at the early stage of incubation. Our results indicated that N amendment promoted more efficiently the proliferation of G+ bacteria and accelerated the decomposition of relatively recalcitrant biochar C, which in turn reduced the stability of maize straw-derived biochar in test soil.

  15. Nitrogen Amendment Stimulated Decomposition of Maize Straw-Derived Biochar in a Sandy Loam Soil: A Short-Term Study

    PubMed Central

    Lu, Weiwei; Ding, Weixin; Zhang, Junhua; Zhang, Huanjun; Luo, Jiafa; Bolan, Nanthi

    2015-01-01

    This study examined the effect of nitrogen (N) on biochar stability in relation to soil microbial community as well as biochar labile components using δ13C stable isotope technology. A sandy loam soil under a long-term rotation of C3 crops was amended with biochar produced from maize (a C4 plant) straw in absence (BC0) and presence (BCN) of N and monitored for dynamics of carbon dioxide (CO2) flux, phospholipid fatty acids (PLFAs) profile and dissolved organic carbon (DOC) content. N amendment significantly increased the decomposition of biochar during the first 5 days of incubation (P < 0.05), and the proportions of decomposed biochar carbon (C) were 2.30% and 3.28% in BC0 and BCN treatments, respectively, during 30 days of incubation. The magnitude of decomposed biochar C was significantly (P < 0.05) higher than DOC in biochar (1.75%) and part of relatively recalcitrant biochar C was mineralized in both treatments. N amendment increased soil PLFAs concentration at the beginning of incubation, indicating that microorganisms were N-limited in test soil. Furthermore, N amendment significantly (P < 0.05) increased the proportion of gram-positive (G+) bacteria and decreased that of fungi, while no noticeable changes were observed for gram-negative (G−) bacteria and actinobacteria at the early stage of incubation. Our results indicated that N amendment promoted more efficiently the proliferation of G+ bacteria and accelerated the decomposition of relatively recalcitrant biochar C, which in turn reduced the stability of maize straw-derived biochar in test soil. PMID:26192282

  16. Use of organic amendments as a bioremediation strategy to reduce the bioavailability of chlorpyrifos insecticide in soils. Effects on soil biology.

    PubMed

    Tejada, Manuel; Gómez, Isidoro; Del Toro, Marina

    2011-10-01

    The sorption capacity of both an organic municipal solid waste by-product (MSW) and a cow manure (CM) in a soil polluted with chlorpyrifos, as well as its effect on soil microbial activity, and weight, reproductive parameters and glutathione-S-transferase activity of two earthworm species (Eisenia fetida and Lumbricus terrestris) were studied. Chlorpyrifos was added at the recommended application rate (5 L ha(-1); 768 mg chlorpyrifos kg(-1)) and treated with MSW at a rate of 10% and CM at a rate of 5.8% in order to apply the same amount of organic matter to the soil. An unamended polluted soil was used as control. Earthworm cocoon number, average weight of cocoon, and number of juveniles per cocoon were measured after 30 days of incubation, whereas soil enzymatic activities, earthworm weight, and glutathione-S-transferase activity of earthworms were measured after 3, 45 and 90 days. Soil enzymatic activities, reproductive and glutathione-S-transferase activity in both worms decreased in polluted soil. The inhibition percentage of soil enzymatic activities, reproductive and glutathione-S-transferase activity in both worms was lower in MSW-amended soil than for CM-amended soil. The toxic effect of chlorpyrifos on E. fetida was lowest compared to L. terrestris. This suggested that the addition of organic wastes with higher humic than fulvic acid concentration is more beneficial for remediation of soils polluted with chlorpyrifos. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Phosphorus leaching from soils amended with thermally gasified piggery waste ash.

    PubMed

    Kuligowski, Ksawery; Poulsen, Tjalfe Gorm

    2009-09-01

    In regions with intensive livestock farming, thermal treatment for local energy extraction from the manure and export of the P rich ash as a fertilizer has gained interest. One of the main risks associated with P fertilizers is eutrophication of water bodies. In this study P and K mobility in ash from anaerobically digested, thermally gasified (GA) and incinerated (IA) piggery waste has been tested using water loads ranging from 0.1 to 200 ml g(-1). Leaching of P from soil columns amended with GA was investigated for one P application rate (205 kg P ha(-1) corresponding to 91 mg P kg(-1) soil dry matter) as a function of precipitation rate (9.5 and 2.5 mm h(-1)), soil type (Jyndevad agricultural soil and sand), amount of time elapsed between ash amendment and onset of precipitation (0 and 5 weeks) and compared to leaching from soils amended with a commercial fertilizer (Na(2)HPO(4)). Water soluble P in GA and IA constituted 0.04% and 0.8% of total ash P. Ash amended soil released much less P (0.35% of total P applied in sand) than Na(2)HPO(4) (97% and 12% of total P applied in Jyndevad and sand, respectively).

  18. Biochar and compost as amendments in copper-enriched vineyard soils - stabilization or mobilization of copper?

    NASA Astrophysics Data System (ADS)

    Soja, Gerhard; Fristak, Vladimir; Wimmer, Bernhard; Bell, Stephen; Chamier Glisczinski, Julia; Pardeller, Georg; Dersch, Georg; Rosner, Franz; Wenzel, Walter; Zehetner, Franz

    2016-04-01

    Copper is an important ingredient for several fungicides that have been used in agriculture. For organic viticulture, several diseases as e.g. downy mildew (Plasmopara viticola) can only be antagonized with Cu-containing fungicides. This long-lasting dependence on Cu-fungicides has led to a gradual Cu enrichment of vineyard soils in traditional wine-growing areas, occasionally exceeding 300 mg/kg. Although these concentrations do not affect the vines or wine quality, they may impair soil microbiological functions in the top soil layer or the root growth of green cover plants. Therefore measures are demanded that reduce the bioavailability of copper, thereby reducing the ecotoxicological effects. The use of biochar and compost as soil amendment has been suggested as a strategy to immobilize Cu and reduce the exchangeable fractions. This study consisted of lab and greenhouse experiments that were designed to test the sorption and desorption behavior of copper in vineyard soils with or without biochar and/or compost as soil amendment. Slightly acidic soils (pH<6) showed a clearer biochar-induced immobilization of copper with biochar than neutral or alkaline soils. The analyses of leachate waters of microlysimeter experiments showed that the biochar effects were more evident for a reduction of the ionic form Cu2+ than for total soluble copper, even in alkaline soils. Biochar modified with citric or tartaric acid did not significantly decrease the solubility of copper based on total dissolved concentrations although CEC was higher than in unmodified biochar. Treatments consisting of compost only or that had an equal amount of compost and biochar rather had a mobilizing effect on biochar. Sorption experiments with different DOC concentrations and biochar, however, showed a positive effect on copper sorption. Apparently in vineyard soils the predisposition to form organic-Cu-complexes may outbalance the binding possibilities of these complexes to biochar, occasionally

  19. EVALUATION OF A SOIL AMENDMENT PROCESS DEMONSTRATION FOR REDUCING THE BIOAVAILABILITY OF LEAD

    EPA Science Inventory

    The USEPA evaluated an in situ application of a soil amendment process at a residential site that was contaminated with lead. The goal of the evaluation was to determine if the soil amendment process resulted in lower concentrations of bioavailable lead in the contaminated soils...

  20. Soil amendments yield persisting effects on the microbial communities--a 7-year study

    USDA-ARS?s Scientific Manuscript database

    Soil microbial communities are sensitive to carbon amendments and largely control the decomposition and accumulation of soil organic matter. In this study, we evaluated whether the type of carbon amendment applied to wheat-cropped or fallow soil imparted lasting effects on the microbial community w...

  1. Organic and inorganic amendment application on mercury-polluted soils: effects on soil chemical and biochemical properties.

    PubMed

    García-Sánchez, Mercedes; Klouza, Martin; Holečková, Zlata; Tlustoš, Pavel; Száková, Jiřina

    2016-07-01

    On the basis of a previous study performed in our laboratory, the use of organic and inorganic amendments can significantly modify the Hg mobility in soil. We have compared the effectiveness of organic and inorganic amendments such as digestate and fly ash, respectively, reducing the Hg mobility in Chernozem and Luvisol soils differing in their physicochemical properties. Hence, the aim of this work was to compare the impact of digestate and fly ash application on the chemical and biochemical parameters in these two mercury-contaminated soils in a model batch experiment. Chernozem and Luvisol soils were artificially contaminated with Hg and then incubated under controlled conditions for 21 days. Digestate and fly ash were applied to both soils in a dose of 10 and 1.5 %, respectively, and soil samples were collected after 1, 7, 14, and 21 days of incubation. The presence of Hg in both soils negatively affected to processes such as nitrification, provoked a decline in the soil microbial biomass C (soil microbial biomass C (MBC)), and the microbial activities (arylsulfatase, and β-glucosaminidase) in both soils. Meanwhile, the digestate addition to Chernozem and Luvisol soils contaminated with Hg improved the soil chemical properties (pH, dissolved organic carbon (DOC), N (Ntot), inorganic-N forms (N-NH4 (+) and N-NO3 (-))), as consequence of high content in C and N contained in digestate. Likewise, the soil MBC and soil microbial activities (dehydrogenase, arylsulfatase, and β-glucosaminidase) were greatly enhanced by the digestate application in both soils. In contrast, fly ash application did not have a remarkable positive effect when compared to digestate in Chernozem and Luvisol soil contaminated with mercury. These results may indicate that the use of organic amendments such as digestate considerably improved the soil health in Chernozem and Luvisol compared with fly ash, alleviating the detrimental impact of Hg. Probably, the chemical properties present in

  2. ADSORPTION OF CADMIUM ONTO DIFFERENT FRACTIONS OF BIOSOLID-AMENDED SOILS

    EPA Science Inventory

    We hypothesized not only organic but also inorganic fraction in biosolids controls the metal availability in soil systems. To test this hypothesis we conducted Cd adsorption experiments on different fractions of biosolids, biosolid amended soils, and unamended soils. Soils were c...

  3. Effect of synthetic and natural water-absorbing soil amendments on photosynthesis characteristics and tuber nutritional quality of potato in a semi-arid region.

    PubMed

    Xu, Shengtao; Zhang, Lei; McLaughlin, Neil B; Mi, Junzhen; Chen, Qin; Liu, Jinghui

    2016-02-01

    The effect of water-absorbing soil amendments on photosynthesis characteristics and tuber nutritional quality was investigated in a field experiment in a semi-arid region in northern China in 2010-2012. Treatments included two synthetic water-absorbing amendments, potassium polyacrylate (PAA) and polyacrylamide (PAM), and one natural amendment, humic acid (HA), both as single amendments and compound amendments (HA combined with PAA or PAM), and a no amendment control. Soil amendments had a highly significant effect (P ≤ 0.01) on photosynthesis characteristics, dry biomass, crop root/shoot (R/S) ratio and tuber nutritional quality. They improved both dry biomass above ground and dry biomass underground in the whole growing season by 4.6-31.2 and 1.1-83.1% respectively in all three years. Crop R/S ratio was reduced in the early growing season by 2.0-29.4% and increased in the later growing season by 2.3-32.6%. Soil amendments improved leaf soil plant analysis development value, net photosynthesis rate, stomatal conductance and transpiration rate by 1.4-17.0, 5.1-45.9, 2.4-90.6 and 2.0-22.6% respectively and reduced intercellular CO2 concentration by 2.1-19.5% in all three years. Amendment treatment with PAM + HA always had the greatest effect on photosynthesis characteristics and tuber nutritional quality among all amendment treatments and thus merits further research. © 2015 Society of Chemical Industry.

  4. Influence of soil amendments made from digestate on soil physics and the growth of spring wheat

    NASA Astrophysics Data System (ADS)

    Dietrich, Nils; Knoop, Christine; Raab, Thomas; Krümmelbein, Julia

    2016-04-01

    Every year 13 million tons of organic wastes accumulate in Germany. These wastes are a potential alternative for the production of energy in biogas plants, especially because the financial subventions for the cultivation of renewable resources for energy production were omitted in 2014. The production of energy from biomass and organic wastes in biogas plants results in the accumulation of digestate and therefore causes the need for a sustainable strategy of the utilization of these residues. Within the scope of the BMBF-funded project 'VeNGA - Investigations for recovery and nutrient use as well as soil and plant-related effects of digestate from waste fermentation' the application of processed digestate as soil amendments is examined. Therefore we tested four different mechanical treatment processes (rolled pellets, pressed pellets, shredded compost and sieved compost) to produce soil amendments from digestate with regard to their impact on soil physics, soil chemistry and the interactions between plants and soil. Pot experiments with soil amendments were performed in the greenhouse experiment with spring wheat and in field trials with millet, mustard and forage rye. After the first year of the experiment, preliminary results indicate a positive effect of the sieved compost and the rolled pellets on biomass yield of spring wheat as compared to the other variations. First results from the Investigation on soil physics show that rolled pellets have a positive effect on the soil properties by influencing size and distribution of pores resulting in an increased water holding capacity. Further ongoing enhancements of the physical and chemical properties of the soil amendments indicate promising results regarding the ecological effects by increased root growth of spring wheat.

  5. Effect of biochar amendments on microbial transport through soils

    USDA-ARS?s Scientific Manuscript database

    The incorporation of biochar into soils had been shown to improve soil fertility, enhance soil sequestration of carbon and decrease the mobility of agrochemicals and heavy metals. Our series of column experiments have shown that in addition to these benefits, biochar amendments can limit bacterial t...

  6. Organic amendments and nutrient leaching in soil columns

    USDA-ARS?s Scientific Manuscript database

    The lack of nutrient build up in reclaimed coal mine soils would therefore require additional inputs to maintain plant productivity and establishment of a healthy ecosystem. In a greenhouse experiment, reclaimed coal mine soil were amended with fresh and composted poultry manure at the rates based ...

  7. Arsenic in Soils and Forages from Poultry Litter-Amended Pastures

    PubMed Central

    Ashjaei, Shadi; Miller, William P.; Cabrera, Miguel L.; Hassan, Sayed M.

    2011-01-01

    In regions of concentrated poultry production, poultry litter (PL) that contains significant quantities of trace elements is commonly surface-applied to pastures at high levels over multiple years. This study examined the effect of long-term applications of PL on soil concentrations of arsenic (As), copper (Cu), Zinc (Zn), and the uptake of these elements by bermuda grass grown on Cecil (well-drained) and Sedgefield (somewhat poorly-drained) soils. The results showed that concentrations of As, Cu, and Zn in soils that had received surface-applied PL over a 14-year period were significantly greater than untreated soil at 0–2.5 and 2.5–7.5 cm depths. However, the levels were well below the USEPA loading limits established for municipal biosolids. Arsenic fractionation showed that concentrations of all As fractions were significantly greater in PL-amended soils compared to untreated soils at 0–2.5 and 2.5–7.5 cm depths. The residual fraction was the predominant form of As in all soils. The water-soluble and NaHCO3-associated As were only 2% of the total As. Significant differences were found in concentrations of these trace elements and phosphorus (P) in forage from PL-amended soils compared to that in untreated plots. The concentrations of Cu, Zn, As, and P were significantly greater in forage from Sedgefield amended soil compared to Cecil soil, but were in all cases below levels of environmental concern. PMID:21655135

  8. Effect of dolomite and biochar addition on N2O and CO2 emissions from acidic tea field soil

    PubMed Central

    Win, Khin Thuzar; Shibata, Akira; Yamamoto, Akinori; Sano, Tomohito; Hirono, Yuhei

    2018-01-01

    A laboratory study was conducted to study the effects of liming and different biochar amendments on N2O and CO2 emissions from acidic tea field soil. The first experiment was done with three different rates of N treatment; N 300 (300 kg N ha-1), N 600 (600 kg N ha-1) and N 900 (900 kg N ha-1) and four different rates of bamboo biochar amendment; 0%, 0.5%, 1% and 2% biochar. The second experiment was done with three different biochars at a rate of 2% (rice husk, sawdust, and bamboo) and a control and lime treatment (dolomite) and control at two moisture levels (50% and 90% water filled pore space (WFPS)). The results showed that dolomite and biochar amendment significantly increased soil pH. However, only biochar amendment showed a significant increase in total carbon (C), C/N (the ratio of total carbon and total nitrogen), and C/IN ratio (the ratio of total carbon and inorganic nitrogen) at the end of incubation. Reduction in soil NO3--N concentration was observed under different biochar amendments. Bamboo biochar with the rates of 0.5, 1 and 2% reduced cumulative N2O emission by 38%, 48% and 61%, respectively, compare to the control soil in experiment 1. Dolomite and biochar, either alone or combined significantly reduced cumulative N2O emission by 4.6% to 32.7% in experiment 2. Reduction in N2O production under biochar amendment was due to increases in soil pH and decreases in the magnitude of mineral-N in soil. Although, both dolomite and biochar increased cumulative CO2 emission, only biochar amendment had a significant effect. The present study suggests that application of dolomite and biochar to acidic tea field soil can mitigate N2O emissions. PMID:29394272

  9. Effect of dolomite and biochar addition on N2O and CO2 emissions from acidic tea field soil.

    PubMed

    Oo, Aung Zaw; Sudo, Shigeto; Akiyama, Hiroko; Win, Khin Thuzar; Shibata, Akira; Yamamoto, Akinori; Sano, Tomohito; Hirono, Yuhei

    2018-01-01

    A laboratory study was conducted to study the effects of liming and different biochar amendments on N2O and CO2 emissions from acidic tea field soil. The first experiment was done with three different rates of N treatment; N 300 (300 kg N ha-1), N 600 (600 kg N ha-1) and N 900 (900 kg N ha-1) and four different rates of bamboo biochar amendment; 0%, 0.5%, 1% and 2% biochar. The second experiment was done with three different biochars at a rate of 2% (rice husk, sawdust, and bamboo) and a control and lime treatment (dolomite) and control at two moisture levels (50% and 90% water filled pore space (WFPS)). The results showed that dolomite and biochar amendment significantly increased soil pH. However, only biochar amendment showed a significant increase in total carbon (C), C/N (the ratio of total carbon and total nitrogen), and C/IN ratio (the ratio of total carbon and inorganic nitrogen) at the end of incubation. Reduction in soil NO3--N concentration was observed under different biochar amendments. Bamboo biochar with the rates of 0.5, 1 and 2% reduced cumulative N2O emission by 38%, 48% and 61%, respectively, compare to the control soil in experiment 1. Dolomite and biochar, either alone or combined significantly reduced cumulative N2O emission by 4.6% to 32.7% in experiment 2. Reduction in N2O production under biochar amendment was due to increases in soil pH and decreases in the magnitude of mineral-N in soil. Although, both dolomite and biochar increased cumulative CO2 emission, only biochar amendment had a significant effect. The present study suggests that application of dolomite and biochar to acidic tea field soil can mitigate N2O emissions.

  10. Influence of amendments on soil arsenic fractionation and phytoavailability by Pteris vittata L.

    PubMed

    Yan, Xiulan; Zhang, Min; Liao, Xiaoyong; Tu, Shuxin

    2012-06-01

    Increasing availability of soil arsenic is of significance for accelerating phytoremediation efficiency of As-polluted sites. The effects of seven amendments, i.e., citrate, oxalate, EDTA, sodium polyacrylate (SPA), phosphate rock (PR), single superphosphate (SSP), and compost on fractionation and phytoavailability of soil As were investigated in lab culture experiment. The results showed that the addition of PR, SPA, EDTA or compost to soils significantly increased the concentration of NaHCO(3)-extractable As over a 120 d incubation period compared with the control (amendment-free) soil. Then, the four amendments were selected to add to As-contaminated soil growing Pteris vittata. It was concluded that As accumulation by the fern increased significantly under the treatments of PR and SPA by 25% and 31%, respectively. For As fractionation in soil, SPA increased Fe-As significantly by 51% and PR increased Ca-As significantly by 18%, while both the two amendments reduced occluded-As by 16% and 19%, respectively. Adding PR and SPA in soil increased the activities of urease and neutral phosphatase resulting from the improvement the fertility and physical structure of the soil, which benefits plant growth and As absorption of P. vittata. The results of the research revealed that both PR and SPA were effective amendments for improving phytoremediation of As-contaminated sites by P. vittata. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Behavior of N-ethyl perfluorooctane sulfonamido acetic acid (N-EtFOSAA) in biosolids amended soil-plant microcosms of seven plant species: Accumulation and degradation.

    PubMed

    Wen, Bei; Pan, Ying; Shi, Xiaoli; Zhang, Hongna; Hu, Xiaoyu; Huang, Honglin; Lv, Jitao; Zhang, Shuzhen

    2018-06-13

    Perfluorooctane sulfonate (PFOS) precursors have been found extensively in sewage sludge and biosolids-amended soils. The degradation of these precursors are regarded as a significant source of PFOS in the environment. In this study, the accumulation of N-ethyl perfluorooctane sulfonamido acetic acid (N-EtFOSAA) in the plants of seven species, namely alfalfa, lettuce, maize, mung bean, radish, ryegrass, and soybean from biosolids-amended soil, and the degradation kinetics of N-EtFOSAA in soil-plant microcosms were evaluated over 60 days. N-EtFOSAA was found in the roots of all plant species, while was not in stems and leaves. The root concentration factors of N-EtFOSAA ranged 0.52-1.37 (pmol/g root )/(pmol/g soil ). Stepwise multiple regression analysis was used to elucidate the accumulation of N-EtFOSAA in the roots of plants. The results showed that the root protein and lipid contents explain 85.0% of the variation in root N-EtFOSAA levels (P < 0.05). Four degradation products, including N-ethyl perfluorooctane sulfonamide (N-EtFOSA), perfluorooctane sulfonamide acetate (FOSAA), perfluorooctane sulfonamide (FOSA) and PFOS were found in soils and plant roots, stems and leaves, indicating the degradation of N-EtFOSAA in soil-plant system. Degradation kinetics fitted a first-order kinetic model well. Degradation rate constants of N-EtFOSAA in the microcosms with plants ranged 0.063-0.165 d -1 , which was 1.40-3.6 times higher than those without plants. Degradation rate constant of maize was relatively higher than those of other plant species. The results is the first to reveal N-EtFOSAA accumulation in plants and degradation in soil-plant microcosms. Copyright © 2018. Published by Elsevier B.V.

  12. Summer cover crops and soil amendments to improve growth and nutrient uptake of okra

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Q.R.; Li, Y.C.; Klassen, W.

    2006-04-15

    A pot experiment with summer cover crops and soil amendments was conducted in two consecutive years to elucidate the effects of these cover crops and soil amendments on 'Clemson Spineless 80' okra (Abelmoschus esculentus) yields and biomass production, and the uptake and distribution of soil nutrients and trace elements. The cover crops were sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata), velvetbean (Mucuna deeringiana), and sorghum sudan-grass (Sorghum bicolor x S. bicolor var. sudanense) with fallow as the control. The organic soil amendments were biosolids (sediment from wastewater plants), N-Viro Soil (a mixture of biosolids and coal ash), coal ash (amore » combustion by-product from power plants), co-compost (a mixture of 3 biosolids: 7 yard waste), and yard waste compost (mainly from leaves and branches of trees and shrubs, and grass clippings) with a soil-incorporated cover crop as the control. As a subsequent vegetable crop, okra was grown after the cover crops, alone or together with the organic soil amendments, had been incorporated. All of the cover crops, except sorghum sudangrass in 2002-03, significantly improved okra fruit yields and the total biomass production. Both cover crops and soil amendments can substantially improve nutrient uptake and distribution. The results suggest that cover crops and appropriate amounts of soil amendments can be used to improve soil fertility and okra yield without adverse environmental effects or risk of contamination of the fruit. Further field studies will be required to confirm these findings.« less

  13. Amending soils with phosphate as means to mitigate soil lead hazard: a critical review of the state of the science.

    PubMed

    Scheckel, Kirk G; Diamond, Gary L; Burgess, Michele F; Klotzbach, Julie M; Maddaloni, Mark; Miller, Bradley W; Partridge, Charles R; Serda, Sophia M

    2013-01-01

    Ingested soil and surface dust may be important contributors to elevated blood lead (Pb) levels in children exposed to Pb contaminated environments. Mitigation strategies have typically focused on excavation and removal of the contaminated soil. However, this is not always feasible for addressing widely disseminated contamination in populated areas often encountered in urban environments. The rationale for amending soils with phosphate is that phosphate will promote formation of highly insoluble Pb species (e.g., pyromorphite minerals) in soil, which will remain insoluble after ingestion and, therefore, inaccessible to absorption mechanisms in the gastrointestinal tract (GIT). Amending soil with phosphate might potentially be used in combination with other methods that reduce contact with or migration of contaminated soils, such as covering the soil with a green cap such as sod, clean soil with mulch, raised garden beds, or gravel. These remediation strategies may be less expensive and far less disruptive than excavation and removal of soil. This review evaluates evidence for efficacy of phosphate amendments for decreasing soil Pb bioavailability. Evidence is reviewed for (1) physical and chemical interactions of Pb and phosphate that would be expected to influence bioavailability, (2) effects of phosphate amendments on soil Pb bioaccessibility (i.e., predicted solubility of Pb in the GIT), and (3) results of bioavailability bioassays of amended soils conducted in humans and animal models. Practical implementation issues, such as criteria and methods for evaluating efficacy, and potential effects of phosphate on mobility and bioavailability of co-contaminants in soil are also discussed.

  14. Linear spectral unmixing to monitor crop growth in typical organic and inorganic amended arid soil

    NASA Astrophysics Data System (ADS)

    El Battay, A.; Mahmoudi, H.

    2016-06-01

    The soils of the GCC countries are dominantly sandy which is typical of arid regions such as the Arabian Peninsula. Such soils are low in nutrients and have a poor water holding capacity associated with a high infiltration rate. Soil amendments may rehabilitate these soils by restoring essential soil properties and hence enable site revegetation and revitalization for crop production, especially in a region where food security is a priority. In this study, two inorganic amendments; AustraHort and Zeoplant pellet, and one organic locally produced compost were tested as soil amendments at the experimental field of the International Center for Biosaline Agriculture in Dubai, UAE. The main objective is to assess the remote sensing ability to monitor crop growth, for instance Okra (Abelmoschus esculentus), having these amendments, as background with the soil. Three biomass spectral vegetation indices were used namely; NDVI, TDVI and SAVI. Pure spectral signatures of the soil and the three amendments were collected, using a field spectroradiometer, in addition to the spectral signatures of Okra in two growing stages (vegetative and flowering) in the field with a mixed F.O.V of the plant and amended soil during March and May 2015. The spectral signatures were all collected using the FieldSpec® HandHeld 2 (HH2) in the spectral range 325 nm - 1075 nm over 12 plots. A set of 4 plots were assigned for each of the three amendments as follow: three replicates of a 1.5 by 1.5 meter plot with 3kg/m2 of each amendment and 54 plants, one plot as control and all plots were given irrigation treatments at 100% based on ETc. Spectra collected over the plots were inversed in the range of 400-900 nm via a Linear Mixture Model using pure soil and amendments spectral signatures as reference. Field pictures were used to determine the vegetation fraction (in term of area of the F.O.V). Hence, the Okra spectral signatures were isolated for all plots with the three types of amendments. The

  15. The enhancement of atrazine sorption and microbial transformation in biochars amended black soils.

    PubMed

    Yang, Fan; Zhang, Wei; Li, Jinmei; Wang, Shuyao; Tao, Yue; Wang, Yifan; Zhang, Ying

    2017-12-01

    Generally, biochar plays an important role in controlling migration and accumulation of pollutants in soil. In this dissertation, biochars derived from wheat straws at various pyrolysis temperatures are used to investigate how biochar amendment affects adsorption and microbial degradation of atrazine (typical diffuse herbicide) in soils. In order to explore the influence of soil components, soil samples with different organic matter content are collected from typical agricultural sites, which are characterized as black soils in the northeast region of China. The basic sorption characteristics of biochars from wheat straws prepared at diverse pyrolysis temperature are analyzed, along with the comparisons of the sorption difference in the raw soil and soil amended with biochars at four levels of ratio (0.1%, 0.5%, 1.0% and 2.0%). By incubation experiments, atrazine degradation in non-sterile and sterile soils and effects of atrazine degradation rate after biochar amendment are also studied. Atrazine degradation is significantly enhanced in biochar amended soils, which may be because that biochar supplement can promote the growth and metabolism of microorganisms in the soil. Our findings reveal that wheatstraw- derived biochars may be effective remediation reagents for activating degradation of the soil functional microorganism and enhancing sorption of organic matter content, which can be applied to environmental-friendly accelerate the remediation of atrazine contaminated black soils. Copyright © 2017. Published by Elsevier Ltd.

  16. Evaluation of different amendments to stabilize antimony in mining polluted soils.

    PubMed

    Álvarez-Ayuso, E; Otones, V; Murciego, A; García-Sánchez, A

    2013-02-01

    Soil pollution with antimony is of increasing environmental concern worldwide. Measures for its control and to attenuate the risks posed to the ecosystem are required. In this study the application of several iron and aluminium oxides and oxyhydroxides as soil amendments was evaluated in order to assess their feasibility to stabilize Sb in mining polluted soils. Mine soils with different pollution levels were amended with either goethite, ferrihydrite or amorphous Al oxide at various ratios (0-10%). The effectiveness of such treatments was assessed by both batch and column leaching tests. The use of ferrihydrite or amorphous Al oxide proved to be highly effective to stabilize Sb. Immobilization levels of 100% were found when doses of 5% ferrihydrite or 10% amorphous Al oxide were applied, regardless of the soil Sb load. Column leaching studies also showed a high Sb leaching reduction (>75%) when soils were amended with 1% ferrihydrite or 5% amorphous Al oxide. Moreover, such treatments proved to simultaneously immobilize As and Pb in a great extent when soils were also polluted with such toxic elements. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Microbial Profiling of a Suppressiveness-Induced Agricultural Soil Amended with Composted Almond Shells

    PubMed Central

    Vida, Carmen; Bonilla, Nuria; de Vicente, Antonio; Cazorla, Francisco M.

    2016-01-01

    This study focused on the microbial profile present in an agricultural soil that becomes suppressive after the application of composted almond shells (AS) as organic amendments. For this purpose, we analyzed the functions and composition of the complex communities present in an experimental orchard of 40-year-old avocado trees, many of them historically amended with composted almond shells. The role of microbes in the suppression of Rosellinia necatrix, the causative agent of avocado white root rot, was determined after heat-treatment and complementation experiments with different types of soil. Bacterial and fungal profiles obtained from natural soil samples based on the 16S rRNA gene and ITS sequencing revealed slight differences among the amended (AS) and unamended (CT) soils. When the soil was under the influence of composted almond shells as organic amendments, an increase in Proteobacteria and Ascomycota groups was observed, as well as a reduction in Acidobacteria and Mortierellales. Complementary to these findings, functional analysis by GeoChip 4.6 confirmed these subtle differences, mainly present in the relative abundance of genes involved in the carbon cycle. Interestingly, a group of specific probes included in the “soil benefit” category was present only in AS-amended soils, corresponding to specific microorganisms previously described as potential biocontrol agents, such as Pseudomonas spp., Burkholderia spp., or Actinobacteria. Considering the results of both analyses, we determined that AS-amendments to the soil led to an increase in some orders of Gammaproteobacteria, Betaproteobacteria, and Dothideomycetes, as well as a reduction in the abundance of Xylariales fungi (where R. necatrix is allocated). The combination of microbial action and substrate properties of suppressiveness are discussed. PMID:26834725

  18. Influence of triethyl phosphate on phosphatase activity in shooting range soil: Isolation of a zinc-resistant bacterium with an acid phosphatase.

    PubMed

    Story, Sandra; Brigmon, Robin L

    2017-03-01

    Phosphatase-mediated hydrolysis of organic phosphate may be a viable means of stabilizing heavy metals via precipitation as a metal phosphate in bioremediation applications. We investigated the effect of triethyl phosphate (TEP) on soil microbial-phosphatase activity in a heavy-metal contaminated soil. Gaseous TEP has been used at subsurface sites for bioremediation of organic contaminants but not applied in heavy-metal contaminated areas. Little is known about how TEP affects microbial activity in soils and it is postulated that TEP can serve as a phosphate source in nutrient-poor groundwater and soil/sediments. Over a 3-week period, TEP amendment to microcosms containing heavy-metal contaminated soil resulted in increased activity of soil acid-phosphatase and repression of alkaline phosphatase, indicating a stimulatory effect on the microbial population. A soil-free enrichment of microorganisms adapted to heavy-metal and acidic conditions was derived from the TEP-amended soil microcosms using TEP as the sole phosphate source and the selected microbial consortium maintained a high acid-phosphatase activity with repression of alkaline phosphatase. Addition of 5mM zinc to soil-free microcosms had little effect on acid phosphatase but inhibited alkaline phosphatase. One bacterial member from the consortium, identified as Burkholderia cepacia sp., expressed an acid-phosphatase activity uninhibited by high concentrations of zinc and produced a soluble, indigo pigment under phosphate limitation. The pigment was produced in a phosphate-free medium and was not produced in the presence of TEP or phosphate ion, indicative of purple acid-phosphatase types that are pressed by bioavailable phosphate. These results demonstrate that TEP amendment was bioavailable and increased overall phosphatase activity in both soil and soil-free microcosms supporting the possibility of positive outcomes in bioremediation applications. Copyright © 2016. Published by Elsevier Inc.

  19. Effect of wood ash application on soil solution chemistry of tropical acid soils: incubation study.

    PubMed

    Nkana, J C Voundi; Demeyer, A; Verloo, M G

    2002-12-01

    The objective of this study was to determine the effect of wood ash application on soil solution composition of three tropical acid soils. Calcium carbonate was used as a reference amendment. Amended soils and control were incubated for 60 days. To assess soluble nutrients, saturation extracts were analysed at 15 days intervals. Wood ash application affects the soil solution chemistry in two ways, as a liming agent and as a supplier of nutrients. As a liming agent, wood ash application induced increases in soil solution pH, Ca, Mg, inorganic C, SO4 and DOC. As a supplier of elements, the increase in the soil solution pH was partly due to ligand exchange between wood ash SO4 and OH- ions. Large increases in concentrations of inorganic C, SO4, Ca and Mg with wood ash relative to lime and especially increases in K reflected the supply of these elements by wood ash. Wood ash application could represent increased availability of nutrients for the plant. However, large concentrations of basic cations, SO4 and NO3 obtained with higher application rates could be a concern because of potential solute transport to surface waters and groundwater. Wood ash must be applied at reasonable rates to avoid any risk for the environment.

  20. Effect of charcoal amendment on adsorption, leaching and degradation of isoproturon in soils

    NASA Astrophysics Data System (ADS)

    Si, Youbin; Wang, Midao; Tian, Chao; Zhou, Jing; Zhou, Dongmei

    2011-04-01

    The effects of charcoal amendment on adsorption, leaching and degradation of the herbicide isoproturon in soils were studied under laboratory conditions. The adsorption data all fitted well with the Freundlich empirical equation. It was found that the adsorption of isoproturon in soils increased with the rate of charcoal amended (correlation coefficient r = 0.957 **, P < 0.01). The amount of isoproturon in leachate decreased with the increase of the amount of charcoal addition to soil column, while the retention of isoproturon in soils increased with an increase in the charcoal content of soil samples. Biodegradation was still the most significant mechanism for isoproturon dissipation from soil. Charcoal amendment greatly reduced the biodegradation of isoproturon in soils. The half-lives of isoproturon degradation ( DT50) in soils greatly extended when the rate of added charcoal inceased from 0 to 50 g kg - 1 (for Paddy soil, DT50 values increased from 54.6 to 71.4 days; for Alfisol, DT50 from 16.0 to 136 days; and for Vertisol, DT50 from 15.2 to 107 days). The degradation rate of isoproturon in soils was significantly negatively correlated with the amount of added charcoal. This research suggests that charcoal amendment may be an effective management practice for reducing pesticide leaching and enhancing its persistence in soils.

  1. Effect of charcoal amendment on adsorption, leaching and degradation of isoproturon in soils.

    PubMed

    Si, Youbin; Wang, Midao; Tian, Chao; Zhou, Jing; Zhou, Dongmei

    2011-04-01

    The effects of charcoal amendment on adsorption, leaching and degradation of the herbicide isoproturon in soils were studied under laboratory conditions. The adsorption data all fitted well with the Freundlich empirical equation. It was found that the adsorption of isoproturon in soils increased with the rate of charcoal amended (correlation coefficient r=0.957**, P<0.01). The amount of isoproturon in leachate decreased with the increase of the amount of charcoal addition to soil column, while the retention of isoproturon in soils increased with an increase in the charcoal content of soil samples. Biodegradation was still the most significant mechanism for isoproturon dissipation from soil. Charcoal amendment greatly reduced the biodegradation of isoproturon in soils. The half-lives of isoproturon degradation (DT(50)) in soils greatly extended when the rate of added charcoal increased from 0 to 50 g kg(-1) (for Paddy soil, DT(50) values increased from 54.6 to 71.4 days; for Alfisol, DT(50) from 16.0 to 136 days; and for Vertisol, DT(50) from 15.2 to 107 days). The degradation rate of isoproturon in soils was significantly negatively correlated with the amount of added charcoal. This research suggests that charcoal amendment may be an effective management practice for reducing pesticide leaching and enhancing its persistence in soils. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. Short-term effects of different organic amendments on soil chemical, biochemical and biological indicators

    NASA Astrophysics Data System (ADS)

    Mondelli, Donato; Aly, Adel; Yirga Dagnachew, Ababu; Piscitelli, Lea; Dumontet, Stefano; Miano, Teodoro

    2014-05-01

    The limited availability of animal manure and the high cost of good quality compost lead to difficult soil quality management under organic agriculture. Therefore, it is important to find out alternative organic soil amendments and more flexible strategies that are able to sustain crop productivity and maintain and enhance soil quality. A three years study was carried out in the experimental fields of the Mediterranean Agronomic Institute of Bari located in Valenzano, Italy. The main objective of this research is to investigate the effects of different fertility management strategies on soil quality in order to estimate the role of innovative matrices for their use in organic farming. The experiment consists of seven treatments applied to a common crop rotation. The treatments include alternative organic amendments (1- olive mill wastewater OMW, 2- residues of mushroom cultivation MUS, 3- coffee chaff COF), common soil amendments (4- compost COM, 5- faba bean intercropping LEG, 6- cow manure - MAN) and as a reference treatment (7- mineral fertilizer COV). The soil quality was assessed before and after the application of the treatments, through biological (microbial biomass carbon and nitrogen, soil respiration and metabolic quotient), biochemical (soil enzymatic activities: β-glucosidase, alkaline phospatase, urease, fluorescein diacetate (FDA) hydrolysis), and chemical (pH, soil organic carbon, soil organic matter, total nitrogen, available phosphorous, exchangeable potassium, dissolved organic carbon and total dissolved nitrogen) indicators. Based on the results obtained after the second year, all treatments were able to improve various soil chemical parameters as compared to mineral fertilizer. The incorporation of COF and OMW seemed to be more effective in improving soil total N and exchangeable K, while MAN significantly increased available P. All the amendments enhance dissolved organic C, soil respiration, microbial biomass and metabolic quotient as

  3. Arsenic bioaccessibility and speciation in the soils amended with organoarsenicals and drinking-water treatment residuals based on a long-term greenhouse study

    NASA Astrophysics Data System (ADS)

    Nagar, Rachana; Sarkar, Dibyendu; Makris, Konstantinos C.; Datta, Rupali

    2014-10-01

    SummaryAlthough organoarsenical pesticides are no longer applied to agricultural fields in the US, their widespread use until recently, toxicity, and potential transformation to inorganic arsenic has raised serious concern. Drinking-water treatment residuals (WTRs) have been proposed as a low-cost amendment for remediation of organoarsenical pesticide contaminated soils. A long-term greenhouse study was initiated to evaluate the effect WTR application on bioaccessibility, geochemical partitioning, and speciation of the Dimethylarsinic acid (DMA). Two soils (Immokalee and Orelia series) were spiked with DMA (1500 mg As kg-1) and amended with an Al- and Fe-based WTR at two rates (5% and 10% by wt.). Soil sampling was done immediately after spiking (time zero) and after 0.25, 0.5, 1, and 3 (time final) years of equilibration and subjected to bioaccessibility test and sequential extraction. Results showed that compared to the unamended (no WTR) control, As bioaccessibility in the WTR-amended soils significantly (p < 0.001) decreased by 40-70% in 3 years. The Fe-WTR was more effective than Al-WTR in decreasing soil As bioaccessibility. The in vitro and water-extracted samples were subjected to As speciation at time zero and time final. Results showed transformation of DMA into inorganic As, irrespective of WTR amendments. The Orelia soil showed significantly (p < 0.001) higher transformation than the Immokalee soil.

  4. Influence of triethyl phosphate on phosphatase activity in shooting range soil: Isolation of a zinc-resistant bacterium with an acid phosphatase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Story, Sandra; Brigmon, Robin L.

    Phosphatase-mediated hydrolysis of organic phosphate may be a viable means of stabilizing heavy metals via precipitation as a metal phosphate in bioremediation applications. We investigated the effect of triethyl phosphate (TEP) on soil microbial-phosphatase activity in a heavy-metal contaminated soil. Gaseous TEP has been used at subsurface sites for bioremediation of organic contaminants but not applied in heavy-metal contaminated areas. Little is known about how TEP affects microbial activity in soils and it is postulated that TEP can serve as a phosphate source in nutrient-poor groundwater and soil/sediments. Over a 3-week period, TEP amendment to microcosms containing heavy-metal contaminated soilmore » resulted in increased activity of soil acid-phosphatase and repression of alkaline phosphatase, indicating a stimulatory effect on the microbial population. A soil-free enrichment of microorganisms adapted to heavy-metal and acidic conditions was derived from the TEP-amended soil microcosms using TEP as the sole phosphate source and the selected microbial consortium maintained a high acid-phosphatase activity with repression of alkaline phosphatase. Addition of 5 mM zinc to soil-free microcosms had little effect on acid phosphatase but inhibited alkaline phosphatase. One bacterial member from the consortium, identified as Burkholderia cepacia sp., expressed an acid-phosphatase activity uninhibited by high concentrations of zinc and produced a soluble, indigo pigment under phosphate limitation. The pigment was produced in a phosphate-free medium and was not produced in the presence of TEP or phosphate ion, indicative of purple acid-phosphatase types that are pressed by bioavailable phosphate. Finally, these results demonstrate that TEP amendment was bioavailable and increased overall phosphatase activity in both soil and soil-free microcosms supporting the possibility of positive outcomes in bioremediation applications.« less

  5. Influence of triethyl phosphate on phosphatase activity in shooting range soil: Isolation of a zinc-resistant bacterium with an acid phosphatase

    DOE PAGES

    Story, Sandra; Brigmon, Robin L.

    2016-12-19

    Phosphatase-mediated hydrolysis of organic phosphate may be a viable means of stabilizing heavy metals via precipitation as a metal phosphate in bioremediation applications. We investigated the effect of triethyl phosphate (TEP) on soil microbial-phosphatase activity in a heavy-metal contaminated soil. Gaseous TEP has been used at subsurface sites for bioremediation of organic contaminants but not applied in heavy-metal contaminated areas. Little is known about how TEP affects microbial activity in soils and it is postulated that TEP can serve as a phosphate source in nutrient-poor groundwater and soil/sediments. Over a 3-week period, TEP amendment to microcosms containing heavy-metal contaminated soilmore » resulted in increased activity of soil acid-phosphatase and repression of alkaline phosphatase, indicating a stimulatory effect on the microbial population. A soil-free enrichment of microorganisms adapted to heavy-metal and acidic conditions was derived from the TEP-amended soil microcosms using TEP as the sole phosphate source and the selected microbial consortium maintained a high acid-phosphatase activity with repression of alkaline phosphatase. Addition of 5 mM zinc to soil-free microcosms had little effect on acid phosphatase but inhibited alkaline phosphatase. One bacterial member from the consortium, identified as Burkholderia cepacia sp., expressed an acid-phosphatase activity uninhibited by high concentrations of zinc and produced a soluble, indigo pigment under phosphate limitation. The pigment was produced in a phosphate-free medium and was not produced in the presence of TEP or phosphate ion, indicative of purple acid-phosphatase types that are pressed by bioavailable phosphate. Finally, these results demonstrate that TEP amendment was bioavailable and increased overall phosphatase activity in both soil and soil-free microcosms supporting the possibility of positive outcomes in bioremediation applications.« less

  6. The effect of biochar amendment on the soil microbial community - PLFA analyses and 13C labeling results

    NASA Astrophysics Data System (ADS)

    Watzinger, A.; Feichtmair, S.; Rempt, F.; Anders, E.; Wimmer, B.; Kitzler, B.; Zechmeister-Boltenstern, S.; Horacek, M.; Zehetner, F.; Kloss, S.; Richoz, S.; Soja, G.

    2012-04-01

    The effects of biochar amendment on plant growth and on the chemical / physical soil characteristics are well explored but only few studies have investigated the impact on soil microorganisms. The response of the soil microbial community to biochar amendment was investigated by phospholipid fatty acid (PLFA) analysis in (i) a large scale pot experiment, (ii) a small scale pot experiment using 13C labeled biochar and (iii) an incubation study using 13C labeled biochar. In the large scale pot experiment, three different agricultural soils from Austria (Planosol, Cambisol, Chernozem) and four different types of biochar were investigated. In total, 25 treatments with 5 replicates each were set up and monitored over a year. The results from the pot experiments showed no significant influence of biochar amendment on the total microbial biomass in the first 100 days after biochar addition. However, discriminant analysis showed a distinction of biochar and control soils as well as a strong effect of the pyrolysis temperature on the microbial composition. The effect of biochar was dependent on the type of soil. In the Planosol, some PLFAs were affected positively, especially when adding biochar with a low pyrolysis temperature, in the first month. In the long term, microbial community composition altered. Growth of fungi and gram negative bacteria was enhanced. In the Chernozem, PLFAs from various microbial groups decreased in the long term. Variability in the incubation study was low. Consequently, many PLFAs were significantly affected by biochar amendment. Again, in the Planosol, gram negative bacteria, actinomycetes and, after 2 weeks, gram positive bacteria increased under biochar amendment whereas in the chernozem total microbial biomass and gram positive bacteria were negatively affected in the long term. The 13C labeling studies confirmed the low degradability of the biochar, i.e. no alteration of the content and the δ13C in the soil organic matter within 100 days

  7. Impact of FGD gypsum soil amendment applications on soil and environmental quality

    USDA-ARS?s Scientific Manuscript database

    This paper will discuss the utilization of FGD gypsum in agriculture for improving soil quality and other environmental benefits. Gypsum (CaSO4 .2H2O) has been used as an agricultural soil amendment for over 250 years. It is a soluble source of calcium and sulfur- for crops and has been shown to i...

  8. Organic amendments enhance microbial diversity and abundance of functional genes in Australian Soils

    NASA Astrophysics Data System (ADS)

    Aldorri, Sind; McMillan, Mary; Pereg, Lily

    2016-04-01

    Food and cash crops play important roles in Australia's economy with black, grey and red clay soil, widely use for growing cotton, wheat, corn and other crops in rotation. While the majority of cotton growers use nitrogen and phosphate fertilizers only in the form of agrochemicals, a few experiment with the addition of manure or composted plant material before planting. We hypothesized that the use of such organic amendments would enhance the soil microbial function through increased microbial diversity and abundance, thus contribute to improved soil sustainability. To test the hypothesis we collected soil samples from two cotton-growing farms in close geographical proximity and with mostly similar production practices other than one grower has been using composted plants as organic amendment and the second farmer uses only agrochemicals. We applied the Biolog Ecoplate system to study the metabolic signature of microbial communities and used qPCR to estimate the abundance of functional genes in the soil. The soil treated with organic amendments clearly showed higher metabolic activity of a more diverse range of carbon sources as well as higher abundance of genes involved in the nitrogen and phosphorous cycles. Since microbes undertake a large number of soil functions, the use of organic amendments can contribute to the sustainability of agricultural soils.

  9. Pyrolysis temperature influences ameliorating effects of biochars on acidic soil.

    PubMed

    Wan, Qing; Yuan, Jin-Hua; Xu, Ren-Kou; Li, Xing-Hui

    2014-02-01

    The biochars were prepared from straws of canola, corn, soybean, and peanut at different temperatures of 300, 500, and 700 °C by means of oxygen-limited pyrolysis.Amelioration effects of these biochars on an acidic Ultisol were investigated with incubation experiments, and application rate of biochars was 10 g/kg. The incorporation of these biochars induced the increase in soil pH, soil exchangeable base cations, base saturation, and cation exchange capacity and the decrease in soil exchangeable acidity and exchangeable Al. The ameliorating effects of biochars on acidic soil increased with increase in their pyrolysis temperature. The contribution of oxygen-containing functional groups on the biochars to their ameliorating effects on the acidic soil decreased with the rise in pyrolysis temperature, while the contribution from carbonates in the biochars changed oppositely. The incorporation of the biochars led to the decrease in soil reactive Al extracted by 0.5mol/L CuCl2, and the content of reactive Al was decreased with the increase in pyrolysis temperature of incorporated biochars. The biochars generated at 300 °C increased soil organically complexed Al due to ample quantity of oxygen-containing functional groups such as carboxylic and phenolic groups on the biochars, while the biochars generated at 500 and 700 °C accelerated the transformation of soil exchangeable Al to hydroxyl-Al polymers due to hydrolysis of Al at higher pH. Therefore, the crop straw-derived biochars can be used as amendments for acidic soils and the biochars generated at relatively high temperature have great ameliorating effects on the soils.

  10. Assessment of tomato and wine processing solid wastes as soil amendments for biosolarization.

    PubMed

    Achmon, Yigal; Harrold, Duff R; Claypool, Joshua T; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

    2016-02-01

    Pomaces from tomato paste and wine production are the most abundant fruit processing residues in California. These residues were examined as soil amendments for solarization to promote conditions conducive to soil disinfestation (biosolarization). Simulated biosolarization studies were performed in both aerobic and anaerobic soil environments and soil temperature elevation, pH, and evolution of CO2, H2 and CH4 gases were measured as metrics of soil microbial activity. Tomato pomace amendment induced conditions associated with soil pest inactivation, including elevation of soil temperature by up to 2°C for a duration of 4days under aerobic conditions and a reduction of soil pH from 6.5 to 4.68 under anaerobic conditions. White wine grape pomace amendment showed similar trends but to a lesser extent. Red wine grape pomace was generally less suitable for biosolarization due to significantly lower soil temperature elevations, reduced acidification relative to the other pomaces and induction of methanogenesis in the soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Effects of conventional and no-tillage soil management and compost and sludge amendment on soil CO2 fluxes and microbial activities

    NASA Astrophysics Data System (ADS)

    Garcia-Gil, Juan Carlos; Haller, Isabel; Soler-Rovira, Pedro; Polo, Alfredo

    2010-05-01

    Soil management exerts a significant influence on the dynamic of soil organic matter, which is a key issue to enhance soil quality and its ecological functions, but also affects to greenhouse gas emissions and C sequestration processes. The objective of the present research was to determine the influence of soil management (conventional deep-tillage and no-tillage) and the application of two different organic amendment -thermally-dry sewage sludge (TSL) and municipal waste compost (MWC)- on soil CO2 fluxes and microbial activities in a long-term field experiment under semi-arid conditions. Both organic amendments were applied at a rate of 30 t ha-1 prior to sowing a barley crop. The experiment was conducted on an agricultural soil (Calcic Luvisol) from the experimental farm "La Higueruela" (Santa Olalla, Toledo). Unamended soils were used as control in both conventional and no-tillage management. During the course of the experiment, soil CO2 fluxes, microbial biomass C (MBC) and enzyme activities involved in the biogeochemical cycles of C, N and P were monitored during 12 months. The results obtained during the experiment for soil CO2 fluxes showed a great seasonal fluctuation due to semi-arid climate conditions. Overall, conventional deep-tillage soils exhibited higher CO2 fluxes, which was particularly larger during the first hours after deep-tillage was performed, and smaller MBC content and significantly lower dehydrogenase, beta-glucosidase, phosphatase, urease and BAA protease activities than no-tillage soils. Both MWC and TSL amendments provoked a significant increase of CO2 fluxes in both conventional and no-tillage soils, which was larger in TSL amended soils and particularly in no-tillage soils. The application of these organic amendments also enhanced MBC content and the overall enzyme activities in amended soils, which indicate a global revitalization of soil microbial metabolism in response to the fresh input of organic compounds that are energy

  12. Anaerobic soil disinfestation and Brassica seed meal amendment alter soil microbiology and system resistance

    USDA-ARS?s Scientific Manuscript database

    Brassica seed meal amendments and anaerobic soil disinfestation control a spectrum of soil-borne plant pathogens via a diversity of mechanisms. Transformations in microbial community structure and function in certain instances were determinants of disease control and enhanced plant performance. Fo...

  13. Removal of Chromium from Soils Cultivated with Maize (Zea Mays) After the Addition of Natural Minerals as Soil Amendments.

    PubMed

    Μolla, A; Ioannou, Z; Mollas, S; Skoufogianni, E; Dimirkou, A

    2017-03-01

    The efficiency of natural minerals, i.e. zeolite, bentonite and goethite, regarding the retention of chromium, from maize was examined. Specifically, 1.0 kg of soil, 1.0 g of soil amendment and either 50 mg L -1 Cr(III) or 1 mg L -1 Cr(VI) were added in plant pots. Then, seeds of maize were cultivated. Each treatment was repeated three times. The statistical results of the experiments were analyzed by LSD test. Cr(III) addition in soil has shown that zeolite was the only amendment that increased the dry weight. Zeolite and bentonite reduced significantly the total chromium in plants after the addition of 50 mg L -1 Cr(III). The addition of Cr(VI) in soil has shown that bentonite was the only amendment that increased the dry weight of biomass and the plants' height. All soil amendments reduced to zero the total chromium concentration measured to plants after the addition of 1 mg L -1 Cr(VI).

  14. Effects of soil dilution and amendments (mussel shell, cow bone, and biochar) on Pb availability and phytotoxicity in military shooting range soil.

    PubMed

    Ahmad, Mahtab; Soo Lee, Sang; Yang, Jae E; Ro, Hee-Myong; Han Lee, Young; Sik Ok, Yong

    2012-05-01

    Bioavailability and bioaccessibility determine the level of metal toxicity in the soils. Inorganic soil amendments may decrease metal bioavailability and enhance soil quality. This study used mussel shell, cow bone, and biochar to reduce lead (Pb) toxicity in the highly contaminated military shooting range soil in Korea. Water-soluble and 1-M ammonium nitrate extractions, and a modified physiologically based extraction test (PBET) were performed to determine Pb bioavailability and bioaccessibility in the soil, respectively. Active C in the soil was also measured to evaluate the effects of the amendments on biological soil quality. The Pb contaminated soil was diluted in serial with uncontaminated soil for the bioassays. Seed germination and root elongation tests using lettuce (Lactuca sativa) showed increases in germination percentage and root length in soil treated with the amendments. Biochar was most effective and increased seed germination by 360% and root length by 189% compared to the unamended soil. Up to 20% soil dilution resulted in more than 50% seed germination. Bioavailability and bioaccessibility of Pb in the soils were decreased by 92.5% and 48.5% with mussel shell, by 84.8% and 34.5% with cow bone, and by 75.8% and 12.5% with biochar, respectively, compared to the unamended soil. We found that the Pb availability in the military shooting range soil can be reduced effectively by the tested amendments or soil dilution alternately, thereby decreasing the risk of ecotoxicity. Furthermore, the increasing active C from the amendments revitalized the soil contaminated with Pb. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Characteristics of biomass ashes from different materials and their ameliorative effects on acid soils.

    PubMed

    Shi, Renyong; Li, Jiuyu; Jiang, Jun; Mehmood, Khalid; Liu, Yuan; Xu, Renkou; Qian, Wei

    2017-05-01

    The chemical characteristics, element contents, mineral compositions, and the ameliorative effects on acid soils of five biomass ashes from different materials were analyzed. The chemical properties of the ashes varied depending on the source biomass material. An increase in the concrete shuttering contents in the biomass materials led to higher alkalinity, and higher Ca and Mg levels in biomass ashes, which made them particularly good at ameliorating effects on soil acidity. However, heavy metal contents, such as Cr, Cu, and Zn in the ashes, were relatively high. The incorporation of all ashes increased soil pH, exchangeable base cations, and available phosphorus, but decreased soil exchangeable acidity. The application of the ashes from biomass materials with a high concrete shuttering content increased the soil available heavy metal contents. Therefore, the biomass ashes from wood and crop residues with low concrete contents were the better acid soil amendments. Copyright © 2016. Published by Elsevier B.V.

  16. Nitrous oxide emission reduction in temperate biochar-amended soils

    NASA Astrophysics Data System (ADS)

    Felber, R.; Hüppi, R.; Leifeld, J.; Neftel, A.

    2012-01-01

    Biochar, a pyrolysis product of organic residues, is an amendment for agricultural soils to improve soil fertility, sequester CO2 and reduce greenhouse gas (GHG) emissions. In highly weathered tropical soils laboratory incubations of soil-biochar mixtures revealed substantial reductions for nitrous oxide (N2O) and carbon dioxide (CO2). In contrast, evidence is scarce for temperate soils. In a three-factorial laboratory incubation experiment two different temperate agricultural soils were amended with green waste and coffee grounds biochar. N2O and CO2 emissions were measured at the beginning and end of a three month incubation. The experiments were conducted under three different conditions (no additional nutrients, glucose addition, and nitrate and glucose addition) representing different field conditions. We found mean N2O emission reductions of 60 % compared to soils without addition of biochar. The reduction depended on biochar type and soil type as well as on the age of the samples. CO2 emissions were slightly reduced, too. NO3- but not NH4+ concentrations were significantly reduced shortly after biochar incorporation. Despite the highly significant suppression of N2O emissions biochar effects should not be transferred one-to-one to field conditions but need to be tested accordingly.

  17. Greenhouse gas emissions and soil properties following amendment with manure-derived biochars: Influence of pyrolysis temperature and feedstock type.

    PubMed

    Subedi, Raghunath; Taupe, Natalie; Pelissetti, Simone; Petruzzelli, Laura; Bertora, Chiara; Leahy, James J; Grignani, Carlo

    2016-01-15

    Manure-derived biochars can offer a potential option for the stabilization of manure, while mitigating climate change through carbon sequestration and the attenuation of nitrous oxide emission. A laboratory incubation study was conducted to assess the effects of four different manure-derived biochars produced from different feedstocks (poultry litter and swine manure) at different temperatures (400 or 600 °C). A commonly available standard wood chip biochar, produced at a greater temperature (1000 °C), and non-amended treatments were used as references. Two different soils (sandy and silt-loam) were amended with 2% (w/w) biochar on a dry soil weight basis (corresponding to 20 Mg ha(-1)), with the soil moisture being adjusted to 75% saturation level. After a pre-incubation period (21 days), 170 kg N ha(-1) of NH4NO3 fertilizer was added. Measurements of CO2, N2O, CH4 emissions and soil N mineralisation were carried out on different days during the 85 days of incubation. The net C mineralization and N2O emissions from both soils amended with poultry litter biochar at 400 °C were significantly greater than the other biochar treatments. Nitrate availability was greater in both soils in which the manure-derived biochar was used instead of the standard biochar. All of the biochars increased the pH of the silt-loam, sub-acid soil, but failed to improve the cation exchange capacities (CEC) in either soil. Total C and N, P, K and Mg (except Ca) were significantly increased in the manure-derived biochar amended soils, compared to the Control, and were positively correlated to the biochar nutrient contents. This study indicates that the soil application of biochar engenders effects that can vary considerably according to the biochar properties, as determined on the basis of the feedstock types and process conditions. Low-temperature biochar production from manure represents a possible way of producing a soil amendment that can stabilize C while supplying a

  18. Role of organic amendments on enhanced bioremediation of heavy metal(loid) contaminated soils.

    PubMed

    Park, Jin Hee; Lamb, Dane; Paneerselvam, Periyasamy; Choppala, Girish; Bolan, Nanthi; Chung, Jae-Woo

    2011-01-30

    As land application becomes one of the important waste utilization and disposal practices, soil is increasingly being seen as a major source of metal(loid)s reaching food chain, mainly through plant uptake and animal transfer. With greater public awareness of the implications of contaminated soils on human and animal health there has been increasing interest in developing technologies to remediate contaminated sites. Bioremediation is a natural process which relies on soil microorganisms and higher plants to alter metal(loid) bioavailability and can be enhanced by addition of organic amendments to soils. Large quantities of organic amendments, such as manure compost, biosolid and municipal solid wastes are used as a source of nutrients and also as a conditioner to improve the physical properties and fertility of soils. These organic amendments that are low in metal(loid)s can be used as a sink for reducing the bioavailability of metal(loid)s in contaminated soils and sediments through their effect on the adsorption, complexation, reduction and volatilization of metal(loid)s. This review examines the mechanisms for the enhanced bioremediation of metal(loid)s by organic amendments and discusses the practical implications in relation to sequestration and bioavailability of metal(loid)s in soils. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Surfactant-Modified Soil Amendments Reduce Nitrogen and Phosphorus Leaching in a Sand-Based Rootzone.

    PubMed

    Shaddox, Travis W; Kruse, Jason K; Miller, Grady L; Nkedi-Kizza, Peter; Sartain, Jerry B

    2016-09-01

    United States Golf Association putting greens are susceptible to nitrogen (N) and phosphorus (P) leaching. Inorganic soil amendments are used to increase moisture and nutrient retention and may influence N and P leaching. This study was conducted to determine whether N and P leaching could be reduced using soil amendments and surfactant-modified soil amendments. Treatments included a control (sand), sand-peat, zeolite, calcined clay, hexadecyltrimethylammonium-zeolite, and hexadecyltrimethylammonium-calcined clay. Lysimeters were filled with a 30-cm rootzone layer of sand-peat (85:15 by volume), below which a 5-cm treatment layer of amendments was placed. A solution of NO-N, NH-N, and orthophosphate-P (2300, 2480, and 4400 μg mL, respectively) was injected at the top of each lysimeter, and leachate was collected using an autocollector set to collect a 10-mL sample every min until four pore volumes were collected. Uncoated amendments, sand, and peat had no influence on NO-N retention, whereas hexadecyltrimethylammonium-coated amendments reduced NO-N leaching to below detectable limits. Both coated and uncoated amendments reduced NH-N leaching, with zeolite reducing NH-N leached to near zero regardless of hexadecyltrimethylammonium coating. Pure sand resulted in a 13% reduction of applied orthophosphate-P leaching, whereas peat contributed to orthophosphate-P leaching. Surfactant-modified amendments reduced orthophosphate-P leaching by as much as 97%. Surfactant-modified soil amendments can reduce NO-N, NH-N, and orthophosphate-P leaching and, thus, may be a viable option for removing leached N and P before they enter surface or ground waters. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Persistence of Escherichia coli in manure-amended soil in Pennsylvania

    USDA-ARS?s Scientific Manuscript database

    Potential for pathogen transfer from soils amended with untreated animal manure to crops and the frequent occurrence of foodborne illness outbreaks involving Escherichia coli O157:H7 prompted the FDA proposal requiring a 9-month waiting period before harvesting produce from manure-amended fields. A...

  1. Maize (Zea mays L.) performance in organically amended mine site soils.

    PubMed

    Oladipo, Oluwatosin Gbemisola; Olayinka, Akinyemi; Awotoye, Olusegun Olufemi

    2016-10-01

    Organic amendments play an important role in the eco-friendly remediation of degraded mine site soils. This study investigated the quality (essential nutrients and heavy metal content) of maize grown on organically amended soils from three active mines in Nigeria. Soil samples were collected randomly at 0-15 cm depth, air-dried and sieved. Five kg of soil were amended with poultry manure and sawdust (poultry manure only, sawdust only, poultry manure-sawdust mixtures in 3:1, 2:1 and 1:1 ratios) at 10 g kg(-1). Maize (Zea mays L.) seeds were planted and watered for two consecutive periods of 8 weeks, with the control and treatment experiments set up in the screenhouse in quadruples. Harvested tissues were weighed, dried, ground and digested. Chemical properties were determined using standard methods while atomic absorption spectrophotometry was used to determine total metal concentrations (Ca, Mg, Fe, Zn, Pb, Cd and Cu). ANOVA was used to test for significant differences among treatment groups in the various parameters. Application of poultry manure-sawdust mixtures significantly (p < 0.05) enhanced tissue dry matter yield, as well as N, P, K, and Na contents while Zn, Cd, Cu and Pb were immobilized to approximately 50-100%. Treatment with sawdust alone reduced tissue nutrient content resulting in depressed plant yield while poultry manure only though enhanced crop yield, contained higher heavy metal contents. Soil amendments comprised of poultry manure-sawdust mixtures can be effective remediation strategy for mine site soils, as these organic materials help replenish soil nutrients, immobilize heavy metals, and enhance food productivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Carbon dioxide emissions from agricultural soils amended with livestock-derived organic materials

    NASA Astrophysics Data System (ADS)

    Pezzolla, D.; Said-Pullicino, D.; Gigliotti, G.

    2009-04-01

    Carbon dioxide gas xchange between terrestrial ecosystems and the atmosphere, as well as the carbon sink strength of various arable land ecosystems, is of primary interest for global change research. Measures for increasing soil C inputs include the preferential use of livestock-derived organic materials (e.g. animal manure and slurries, digestate from biogas production plants and compost). The application of such materials to agricultural soils returns essential nutrients for plant growth and organic matter to maintain long-term fertility. Whether or not such practices ultimately result in sustained C sequestration at the ecosystem level will depend on their mineralization rates. This work presents preliminary results from a laboratory incubation trial to evaluate carbon dioxide fluxes from two agricultural soils (a calcareous silt loam and a silty clay loam) amended with agricultural doses of (i) pig slurry (PSL), (ii) the digestate from the anaerobic fermentation of pig slurries (AAS) and (ii) a compost from the aerobic stabilisation of the digestate (LDC). These subsequent steps of slurry stabilisation resulted in a decrease in the content of labile organic matter which was reflected in a reduction in maximum carbon dioxide emission rates from amended soils. Measurements have shown that peak emissions from soils occur immediately after application of these organic materials (within 5 days) and decrease in the order PSL > AAS > LDC. Moreover, mean cumulative emissions over the first 40 days showed that a higher percentage (about 44%) of the C added with PSL was mineralised respect to C added with AAS (39%) and LDC (25%). Although it was hypothesised that apart from the quantity and stability of the added organic materials, even soil characteristics could influence C mineralisation rates, no significant differences were observed between emission fluxes for similarly treated soils. Mean cumulative emission fluxes after 40 days from treatment were of 114, 103 and

  3. Activated carbon amendment to sequester PAHs in contaminated soil: a lysimeter field trial.

    PubMed

    Hale, Sarah E; Elmquist, Marie; Brändli, Rahel; Hartnik, Thomas; Jakob, Lena; Henriksen, Thomas; Werner, David; Cornelissen, Gerard

    2012-04-01

    Activated carbon (AC) amendment is an innovative method for the in situ remediation of contaminated soils. A field-scale AC amendment of either 2% powder or granular AC (PAC and GAC) to a PAH contaminated soil was carried out in Norway. The PAH concentration in drainage water from the field plot was measured with a direct solvent extraction and by deploying polyoxymethylene (POM) passive samplers. In addition, POM samplers were dug directly in the AC amended and unamended soil in order to monitor the reduction in free aqueous PAH concentrations in the soil pore water. The total PAH concentration in the drainage water, measured by direct solvent extraction of the water, was reduced by 14% for the PAC amendment and by 59% for GAC, 12 months after amendment. Measurements carried out with POM showed a reduction of 93% for PAC and 56% for GAC. The free aqueous PAH concentration in soil pore water was reduced 93% and 76%, 17 and 28 months after PAC amendment, compared to 84% and 69% for GAC. PAC, in contrast to GAC, was more effective for reducing freely dissolved concentrations than total dissolved ones. This could tentatively be explained by leaching of microscopic AC particles from PAC. Secondary chemical effects of the AC amendment were monitored by considering concentration changes in dissolved organic carbon (DOC) and nutrients. DOC was bound by AC, while the concentrations of nutrients (NO(3), NO(2), NH(4), PO(4), P-total, K, Ca and Mg) were variable and likely affected by external environmental factors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Plant absorption of trace elements in sludge amended soils and correlation with soil chemical speciation.

    PubMed

    Torri, Silvana; Lavado, Raúl

    2009-07-30

    The aim of the present study was to investigate the relationship between Lolium perenne L. uptake of Cd, Cu, Pb, and Zn in sludge amended soils and soil availability of these elements assessed by soil sequential extraction. A greenhouse experiment was set with three representative soils of the Pampas Region, Argentina, amended with sewage sludge and sewage sludge enriched with its own incinerated ash. After the stabilization period of 60 days, half of the pots were sampled for soil analysis; the rest of the pots were sown with L. perenne and harvested 8, 12, 16 and 20 weeks after sowing, by cutting just above the soil surface. Cadmium and Pb concentrations in aerial tissues of L. perenne were below detection limits, in good agreement with the soil fractionation study. Copper and Zn concentration in the first harvest were significantly higher in the coarse textured soil compared to the fine textured soil, in contrast with soil chemical speciation. In the third harvest, there was a positive correlation between Cu and Zn concentration in aerial biomass and soil fractions usually considered of low availability. We conclude that the most available fractions obtained by soil sequential extraction did not provide the best indicator of Cu and Zn availability to L. perenne.

  5. Use of mixed solid waste as a soil amendment for saline-sodic soil remediation and oat seedling growth improvement.

    PubMed

    Fan, Yuan; Ge, Tian; Zheng, Yanli; Li, Hua; Cheng, Fangqin

    2016-11-01

    Soil salinization has become a worldwide problem that imposes restrictions on crop production and food quality. This study utilizes a soil column experiment to address the potential of using mixed solid waste (vinegar residue, fly ash, and sewage sludge) as soil amendment to ameliorate saline-sodic soil and enhance crop growth. Mixed solid waste with vinegar residue content ranging from 60-90 %, sewage sludge of 8.7-30 %, and fly ash of 1.3-10 % was added to saline-sodic soil (electrical conductivity (EC 1:5 ) = 1.83 dS m -1 , sodium adsorption ratio (SAR 1:5 ) = 129.3 (mmol c L -1 ) 1/2 , pH = 9.73) at rates of 0 (control), 130, 260, and 650 kg ha -1 . Results showed that the application of waste amendment significantly reduced SAR, while increasing soil soluble K + , Ca 2+ , and Mg 2+ , at a dose of 650 kg ha -1 . The wet stability of macro-aggregates (>1 mm) was improved 90.7-133.7 % when the application rate of amendment was greater than 260 kg ha -1 . The application of this amendment significantly reduced soil pH. Germination rates and plant heights of oats were improved with the increasing rate of application. There was a positive correlation between the percentage of vinegar residue and the K/Na ratio in the soil solutions and roots. These findings suggest that applying a mixed waste amendment (vinegar residue, fly ash, and sewage sludge) could be a cost-effective method for the reclamation of saline-sodic soil and the improvement of the growth of salt-tolerant plants.

  6. Dissipation of fragrance materials in sludge-amended soils.

    PubMed

    DiFrancesco, Angela M; Chiu, Pei C; Standley, Laurel J; Allen, Herbert E; Salvito, Daniel T

    2004-01-01

    A possible removal mechanism for fragrance materials (FMs) in wastewater is adsorption to sludge, and sludge application to land may be a route through which FMs are released to the soil environment. However, little is known about the concentrations and fate of FMs in soil receiving sludge application. This study was conducted to better understand the dissipation of FMs in sludge-amended soils. We first determined the spiking and extraction efficiencies for 22 FMs in soil and leachate samples. Nine FMs were detected in digested sludges from two wastewater treatment plants in Delaware using these methods. We conducted a 1-year die-away experiment which involved four different soils amended with sludge, with and without spiking of the 22 FMs. The initial dissipation of FMs in all spiked trays was rapid, and only seven FMs remained at concentrations above the quantification limits after 3 months: AHTN, HHCB, musk ketone, musk xylene, acetyl cedrene, OTNE, and DPMI. After 1 year, the only FMs remaining in all spiked trays were musk ketone and AHTN. DPMI was the only FM that leached significantly from the spiked trays, and no FMs were detected in leachate from any unspiked tray. While soil organic matter content affected the dissipation rate in general, different mechanisms (volatilization, transformation, leaching) appeared to be important for different FMs.

  7. Vermicompost and biochar as bio-conditioners to immobilize heavy metal and improve soil fertility on cadmium contaminated soil under acid rain stress.

    PubMed

    Wang, Ying; Xu, YongAn; Li, Dan; Tang, BiCong; Man, ShuLei; Jia, YiFan; Xu, Heng

    2018-04-15

    This experiment was conducted to investigate the remediation effects of bio-conditioners vermicompost (VC) and biochar (BC) on cadmium contaminated soil under the threat of acid rain, individually and associatively. With the application of soil conditioners, the percentages of HOAc-extractable Cd decreased 5.2-6.8%, 9.0-13.5% and 7.9-12.1% in the groups amended with VC, BC and VC combined BC, respectively. When the pH of rain decreased from 7.0 to 4.0, the activity of acid phosphatase decreased 2.0%, 12.3%, 3.2%, 14.8% in VC, BC, VC combined BC and control groups, individually. This study affirmed that with the application of soil conditioners, the threat of heavy metal along with bioavailability of Cd was depressed, and the properties of soil biochemical indictors were enhanced. Oppositely, the bioavailability of Cd was promoted, and soil microbial viability as well as nutrient contents was inhibited with the spraying of acid rain. The findings indicated that acid deposition played a restrain effect on soil remediation process. Meanwhile, soil conditioners showed potentials to improve soil fertilities and alleviate the stress of acid rain. Copyright © 2017. Published by Elsevier B.V.

  8. Effect of Activated Carbon Amendment on Bacterial Community Structure and Functions in a PAH Impacted Urban Soil

    PubMed Central

    2012-01-01

    We collected urban soil samples impacted by polycyclic aromatic hydrocarbons (PAHs) from a sorbent-based remediation field trial to address concerns about unwanted side-effects of 2% powdered (PAC) or granular (GAC) activated carbon amendment on soil microbiology and pollutant biodegradation. After three years, total microbial cell counts and respiration rates were highest in the GAC amended soil. The predominant bacterial community structure derived from denaturing gradient gel electrophoresis (DGGE) shifted more strongly with time than in response to AC amendment. DGGE band sequencing revealed the presence of taxa with closest affiliations either to known PAH degraders, e.g. Rhodococcus jostii RHA-1, or taxa known to harbor PAH degraders, e.g. Rhodococcus erythropolis, in all soils. Quantification by real-time polymerase chain reaction yielded similar dioxygenases gene copy numbers in unamended, PAC-, or GAC-amended soil. PAH availability assessments in batch tests showed the greatest difference of 75% with and without biocide addition for unamended soil, while the lowest PAH availability overall was measured in PAC-amended, live soil. We conclude that AC had no detrimental effects on soil microbiology, AC-amended soils retained the potential to biodegrade PAHs, but the removal of available pollutants by biodegradation was most notable in unamended soil. PMID:22455603

  9. Effect of activated carbon amendment on bacterial community structure and functions in a PAH impacted urban soil.

    PubMed

    Meynet, Paola; Hale, Sarah E; Davenport, Russell J; Cornelissen, Gerard; Breedveld, Gijs D; Werner, David

    2012-05-01

    We collected urban soil samples impacted by polycyclic aromatic hydrocarbons (PAHs) from a sorbent-based remediation field trial to address concerns about unwanted side-effects of 2% powdered (PAC) or granular (GAC) activated carbon amendment on soil microbiology and pollutant biodegradation. After three years, total microbial cell counts and respiration rates were highest in the GAC amended soil. The predominant bacterial community structure derived from denaturing gradient gel electrophoresis (DGGE) shifted more strongly with time than in response to AC amendment. DGGE band sequencing revealed the presence of taxa with closest affiliations either to known PAH degraders, e.g. Rhodococcus jostii RHA-1, or taxa known to harbor PAH degraders, e.g. Rhodococcus erythropolis, in all soils. Quantification by real-time polymerase chain reaction yielded similar dioxygenases gene copy numbers in unamended, PAC-, or GAC-amended soil. PAH availability assessments in batch tests showed the greatest difference of 75% with and without biocide addition for unamended soil, while the lowest PAH availability overall was measured in PAC-amended, live soil. We conclude that AC had no detrimental effects on soil microbiology, AC-amended soils retained the potential to biodegrade PAHs, but the removal of available pollutants by biodegradation was most notable in unamended soil. © 2012 American Chemical Society

  10. 76 FR 29238 - Methyl Bromide; Cancellation Order for Registration Amendments To Terminate Certain Soil Uses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-20

    ... Order for Registration Amendments To Terminate Certain Soil Uses AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces EPA's order for the amendments to terminate soil... Corporation. 8536-05 Pic-Brom 33 Soil Chemicals Corporation d/b/a Cardinal Professional Products. [[Page 29239...

  11. Soil biochar amendment shapes the composition of N2O-reducing microbial communities.

    PubMed

    Harter, Johannes; Weigold, Pascal; El-Hadidi, Mohamed; Huson, Daniel H; Kappler, Andreas; Behrens, Sebastian

    2016-08-15

    Soil biochar amendment has been described as a promising tool to improve soil quality, sequester carbon, and mitigate nitrous oxide (N2O) emissions. N2O is a potent greenhouse gas. The main sources of N2O in soils are microbially-mediated nitrogen transformation processes such as nitrification and denitrification. While previous studies have focused on the link between N2O emission mitigation and the abundance and activity of N2O-reducing microorganisms in biochar-amended soils, the impact of biochar on the taxonomic composition of the nosZ gene carrying soil microbial community has not been subject of systematic study to date. We used 454 pyrosequencing in order to study the microbial diversity in biochar-amended and biochar-free soil microcosms. We sequenced bacterial 16S rRNA gene amplicons as well as fragments of common (typical) nosZ genes and the recently described 'atypical' nosZ genes. The aim was to describe biochar-induced shifts in general bacterial community diversity and taxonomic variations among the nosZ gene containing N2O-reducing microbial communities. While soil biochar amendment significantly altered the 16S rRNA gene-based community composition and structure, it also led to the development of distinct functional traits capable of N2O reduction containing typical and atypical nosZ genes related to nosZ genes found in Pseudomonas stutzeri and Pedobacter saltans, respectively. Our results showed that biochar amendment can affect the relative abundance and taxonomic composition of N2O-reducing functional microbial traits in soil. Thus these findings broaden our knowledge on the impact of biochar on soil microbial community composition and nitrogen cycling. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Potential effects of vinasse as a soil amendment to control runoff and soil loss

    NASA Astrophysics Data System (ADS)

    Hazbavi, Z.; Sadeghi, S. H. R.

    2016-02-01

    Application of organic materials are well known as environmental practices in soil restoration, preserving soil organic matter and recovering degraded soils of arid and semiarid lands. Therefore, the present research focused on evaluating the effectiveness of vinasse, a byproduct mainly of the sugar-ethanol industry, on soil conservation under simulated rainfall. Vinasse can be recycled as a soil amendment due to its organic matter content. Accordingly, the laboratory experiments were conducted by using 0.25 m2 experimental plots at 20 % slope and rainfall intensity of 72 mm h-1 with 0.5 h duration. The effect of vinasse was investigated on runoff and soil loss control. Experiments were set up as a control (with no amendment) and three treated plots with doses of 0.5, 1, and 1.5 L m-2 of vinasse subjected to simulated rainfall. Laboratory results indicated that vinasse at different levels could not significantly (P > 0.05) decrease the runoff amount and soil loss rate in the study plots compared to untreated plots. The average amounts of minimum runoff volume and soil loss were about 3985 mL and 46 g for the study plot at a 1 L m-2 level of vinasse application.

  13. Assessment of trace element accumulation by earthworms in an orchard soil remediation study using soil amendments

    USGS Publications Warehouse

    Centofantia, Tiziana; Chaney, Rufus L.; Beyer, W. Nelson; McConnell, Laura L.; Davis, A. P.; Jackson, Dana

    2016-01-01

    This study assessed potential bioaccumulation of various trace elements in grasses and earthworms as a consequence of soil incorporation of organic amendments for in situ remediation of an orchard field soil contaminated with organochlorine and Pb pesticide residues. In this experiment, four organic amendments of differing total organic carbon content and quality (two types of composted manure, composted biosolids, and biochar) were added to a contaminated orchard field soil, planted with two types of grasses, and tested for their ability to reduce bioaccumulation of organochlorine pesticides and metals in earthworms. The experiment was carried out in 4-L soil microcosms in a controlled environment for 90 days. After 45 days of orchardgrass or perennial ryegrass growth, Lumbricus terrestris L. were introduced to the microcosms and exposed to the experimental soils for 45 days before the experiment was ended. Total trace element concentrations in the added organic amendments were below recommended safe levels and their phytoavailablity and earthworm availability remained low during a 90-day bioremediation study. At the end of the experiment, total tissue concentrations of Cu, Cd, Mn, Pb, and Zn in earthworms and grasses were below recommended safe levels. Total concentrations of Pb in test soil were similar to maximum background levels of Pb recorded in soils in the Eastern USA (100 mg kg−1 d.w.) because of previous application of orchard pesticides. Addition of aged dairy manure compost and presence of grasses was effective in reducing the accumulation of soil-derived Pb in earthworms, thus reducing the risk of soil Pb entry into wildlife food chains.

  14. Amending the seedling bed of eggplant with biochar can further immobilize Cd in contaminated soils.

    PubMed

    Li, Zhongyang; Qi, Xuebin; Fan, Xiangyang; Du, Zhenjie; Hu, Chao; Zhao, Zhijuan; Isa, Yunusa; Liu, Yuan

    2016-12-01

    Untreated municipal sewage is a potential source of Cd but has been used for irrigating vegetables in many countries in recent years. In growing vegetables and fruits in greenhouses, seedling breeding method is generally used in which the seedlings are transplanted into soils together with their seedling culture. Biochar has been increasingly used to amend soils contaminated by heavy metals, but there are few studies on the effectiveness of different ways of applying the biochar. In this paper, we investigated the efficacy of immobilizing Cd by amending eggplant seedling bed with biochar before transplanting them to biochar-amended soil contaminated by Cd. The results showed that, in comparison with traditional seedling method (without adding biochar), amending the seedling bed by biochar not only had a positive effect on plant growth and production, but further reduced the Cd concentration in the roots, shoots and the fruits by 12.2%, 12.5% and 18.5%, respectively. Furthermore, it increased the pH in rhizosphere to 8.83, reduced the exchangeable Cd concentration in soil by 28.6%, and decreased the Cd bio-accumulation factor from 0.36 to 0.32. Phytochelatin synthesis could be induced when plants are exposed to Cd and it has been used in the literature as a biomarker for evaluating metal toxicity. Our results showed that the seedling culture amended with biochar reduced phytochelatin synthesis in both roots and shoots. It can therefore be concluded that amending the eggplant seedlings bed with biochar can further enhance the effectiveness of remediating Cd contamination in soil after transplanting the plants into soil also amended with biochar. We found a new method to further immobilize Cd in contaminated soils by amending the seedling bed with biochar. Copyright © 2016. Published by Elsevier B.V.

  15. Herbaceous vegetation productivity, persistence, and metals uptake on a biosolids-amended mine soil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Evanylo, G.K.; Abaye, A.O.; Dundas, C.

    The selection of plant species is critical for the successful establishment and long-term maintenance of vegetation on reclaimed surface mined soils. A study was conducted to assess the capability of 16 forage grass and legume species in monocultures and mixes to establish and thrive on a reclaimed Appalachian surface mine amended with biosolids. The 0.15-ha coarse-textured, rocky, non-acid forming mined site was prepared for planting by grading to a 2% slope and amending sandstone overburden materials with a mixture of composted and dewatered, anaerobically digested biosolids at a rate of 368 Mg ha{sup -1} (dry weight). The high rate ofmore » biosolids applied provided favorable soil chemical properties but could not overcome physical property limitations due to shallow undeveloped soil perched atop a compacted soil layer at 25 cm depth. The plant species whose persistence and biomass production were the greatest after a decade or more of establishment (i.e., switchgrass, sericea lespedeza, reed canarygrass, tall fescue, and crownvetch) shared the physiological and reproductive characteristics of low fertility requirements, drought and moisture tolerance, and propagation by rhizome and/or stolons. Of these five species, two (tall fescue and sericea lespedeza) are or have been seeded commonly on Appalachian coal surface mines, and often dominate abandoned pasture sites. Despite the high rates of heavy metal-bearing biosolids applied to the soil, plant uptake of Cd, Cu, Ni, and Zn were well within critical concentrations more than a decade after establishment of the vegetation.« less

  16. Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils.

    PubMed

    Ali, Muhammad Aslam; Kim, P J; Inubushi, K

    2015-10-01

    Effects of different soil amendments were investigated on methane (CH4) and nitrous oxide (N2O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK+fly ash, NPK+silicate slag, NPK+phosphogypsum(PG), NPK+blast furnace slag (BFS), NPK+revolving furnace slag (RFS), NPK+silicate slag (50%)+RFS (50%), NPK+biochar, NPK+biochar+Azolla-cyanobacteria, NPK+silicate slag+Azolla-cyanobacteria, NPK+phosphogypsum (PG)+Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH4 emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N2O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH4 emissions were significantly increased by 9.5-14.0% with biochar amendments, however, global warming potentials were decreased by 8.0-12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0-30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43-50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Short-term changes of metal availability in soil. Part I: comparing sludge-amended with metal-spiked soils.

    PubMed

    Natal-da-Luz, T; Ojeda, G; Costa, M; Pratas, J; Lanno, R P; Van Gestel, C A M; Sousa, J P

    2012-08-01

    Sewage sludge application to soils is regulated by its total metal content. However, the real risk of metals is determined by the fraction that is biologically available. The available fraction is highly related to the strength of metal binding by the matrix, which is a dynamic process. The evaluation of the fate of metals in time can contribute increased accuracy of ecological risk assessment. Aiming to evaluate short-term changes in metal availability when metals were applied to soil directly (metal-spiked) or by way of an organic matrix (sludge-amended), a laboratory experiment was performed using open microcosms filled with agricultural soil. A concentration gradient of industrial sludge (11, 15, 55, and 75 t/ha) that was contaminated predominantly with chromium, copper, nickel, and zinc, or soil freshly spiked with the same concentrations of these metals, were applied on top of the agricultural soil. After 0, 3, 6, and 12 weeks, total (HNO(3) 69 %) and 0.01 M CaCl(2)-extractable metal concentrations in soil and metal content in the percolates were measured. Results demonstrated that comparison between sludge-amended and metal-spiked soils may give important information about the role of sludge matrix on metal mobility and availability in soil. In sludge-amended soils, extractable-metal concentrations were independent of the sludge concentration and did not change over time. In metal-spiked soils, metal extractability decreased with time due to ageing and transport of metals to deeper layers. In general, the sludge matrix increased the adsorption of metals, thus decreasing their mobility in soils.

  18. Zinc distribution in soils amended with different kinds of sewage sludge.

    PubMed

    Torri, Silvana Irene; Lavado, Raúl

    2008-09-01

    Sewage sludge (SS) can be applied to cropland to supply and recycle nutrients and organic carbon. Potentially toxic elements in the sludge, however, are of environmental concern. This study evaluates the changes in chemical speciation of Zn in three representative pristine soils of the Pampas Region, Argentina, measured with sequential extraction over a one-year period. Pure SS or SS containing 30% (DM) of its own incineration ash (AS) was applied to the soils at an application rate of 150 Mg ha(-1). Zn was sequentially fractionated into exchangeable, organically bound, inorganic and residual fractions. The application of the SS and AS amendments significantly increased Zn concentration in all soil fractions at each sampling date. At day 1, Zn was mainly found in the residual fraction. A year after the application of the amendments, redistribution towards the inorganic fraction was observed (41-76% of total Zn content). Zn found in exchangeable and inorganic fractions depended on soil pH rather than on the type of soil used. A negative and significant correlation was found between exchangeable Zn concentrations and soil pH (r=0.94), and a positive and significant correlation between inorganic Zn concentrations and soil pH (r=0.92). For each amended soil and sampling date, no significant differences were observed between SS or AS treatments for the exchangeable fraction. Moreover, the use of AS did not cause significant differences in Zn concentration in the other soil fractions compared to SS. Based on these results, land spreading of AS may be similar to SS diaposal in terms of Zn mobility.

  19. The impact of soil amendments on greenhouse gas emissions: a comprehensive life cycle assessment approach

    NASA Astrophysics Data System (ADS)

    DeLonge, M. S.; Ryals, R.; Silver, W. L.

    2011-12-01

    Soil amendments, such as compost and manure, can be applied to grasslands to improve soil conditions and enhance aboveground net primary productivity. Applying such amendments can also lead to soil carbon (C) sequestration and, when materials are diverted from waste streams (e.g., landfills, manure lagoons), can offset greenhouse gas (GHG) emissions. However, amendment production and application is also associated with GHG emissions, and the net impact of these amendments remains unclear. To investigate the potential for soil amendments to reduce net GHG emissions, we developed a comprehensive, field-scale life cycle assessment (LCA) model. The LCA includes GHG (i.e., CO2, CH4, N2O) emissions of soil amendment production, application, and ecosystem response. Emissions avoided by diverting materials from landfills or manure management systems are also considered. We developed the model using field observations from grazed annual grassland in northern California (e.g., soil C; above- and belowground net primary productivity; C:N ratios; trace gas emissions from soils, manure piles, and composting), CENTURY model simulations (e.g., long-term soil C and trace gas emissions from soils under various land management strategies), and literature values (e.g., GHG emissions from transportation, inorganic fertilizer production, composting, and enteric fermentation). The LCA quantifies and contrasts the potential net GHG impacts of applying compost, manure, and commercial inorganic fertilizer to grazing lands. To estimate the LCA uncertainty, sensitivity tests were performed on the most widely ranging or highly uncertain parameters (e.g., compost materials, landfill emissions, manure management system emissions). Finally, our results are scaled-up to assess the feasibility and potential impacts of large-scale adoption of soil amendment application as a land-management strategy in California. Our base case results indicate that C sinks and emissions offsets associated with

  20. Short-term effect of the soil amendments activated carbon, biochar, and ferric oxyhydroxide on bacteria and invertebrates.

    PubMed

    Hale, Sarah E; Jensen, John; Jakob, Lena; Oleszczuk, Patryk; Hartnik, Thomas; Henriksen, Thomas; Okkenhaug, Gudny; Martinsen, Vegard; Cornelissen, Gerard

    2013-08-06

    The aim of the present study was to evaluate the secondary ecotoxicological effects of soil amendment materials that can be added to contaminated soils in order to sequester harmful pollutants. To this end, a nonpolluted agricultural soil was amended with 0.5, 2, and 5% of the following four amendments: powder activated carbon (PAC), granular activated carbon, corn stover biochar, and ferric oxyhydroxide powder, which have previously been proven to sequester pollutants in soil. The resulting immediate effects (i.e., without aging the mixtures before carrying out tests) on the springtail Folsomia candida, the earthworm species Aporectodea caliginosa and Eisenia fetida, the marine bacteria Vibrio fischeri, a suite of ten prokaryotic species, and a eukaryote (the yeast species Pichia anomalia) were investigated. Reproduction of F. candida was significantly increased compared to the unamended soil when 2% biochar was added to it. None of the treatments caused a negative effect on reproduction. All amendments had a deleterious effect on the growth of A. caliginosa when compared to the unamended soil, except the 0.5% amendment of biochar. In avoidance tests, E. fetida preferred biochar compared to all other amendments including the unamended soil. All amendments reduced the inhibition of luminescence to V. fischeri, i.e., were beneficial for the bacteria, with PAC showing the greatest improvement. The effects of the amendments on the suite of prokaryotic species and the eukaryote were variable, but overall the 2% biochar dose provided the most frequent positive effect on growth. It is concluded that the four soil amendments had variable but never strongly deleterious effects on the bacteria and invertebrates studied here during the respective recommended experimental test periods.

  1. Impact of Ca-amendments and soil management in physical properties linked to soil-water relationship in degraded Ultisols from South-Europe

    NASA Astrophysics Data System (ADS)

    Mariscal-Sancho, I.; Gonzalez-Fernandez, P.; León, P.; Gómez-Paccard, C.; Benito, M.; Espejo, R.

    2012-04-01

    Cañamerós raña formation in western Spain was cleared for cropping in 1940´s. Its highly weathered acidic soils (Ultisols) were deeply affected by tillage. The soil organic matter (SOM) content and specially the particulate organic matter (POM), a labile fraction, were drastically reduced, and most of their chemical and physical soil properties related to its quality were negatively affected. The extraction of Ca through the harvest and the release of Al retained in organic-Al complexes resulted in a lower Ca/Al ratio which increased the Al toxicity. These effects led to a drastic yield reduction and the abandon of many degraded fields after 20-70 years of unsustainable managements. On these degraded soils we studied the effect of different soil management strategies (no-till with wild pasture (WP) and no-till with an improved pasture (IP)), and amendment applications (sugar foam waste (SF), and SF + Phosphogypsum (PH) versus control (C)). One of the objectives of this work was to evaluate the efficiency of these practices to recover soil quality parameters, especially those related to soil-water relationship. A Split-plot experiment was established in a degraded field. We evaluated the changes in superficial infiltration, bulk density, and content of water-stable aggregates per 100 g of soil before the Ca-amendment applications and pasture establishments, and after 4.5 years. We also measured the changes in SOM and POM contents which are closely related with the previous parameters. The Ca applications reduced Al toxicity, improved the pasture yield and increased organic matter inputs to soil. The results showed a significant increase of POM in all treatment compared with the POM content at the beginning of this experiment. However the "SOM minus POM" which could be classified as recalcitrant organic matter did not show significant increments. The increase of POM had a positive effect on the content of water-stable aggregates per 100 g of soil and the water

  2. Use of raw or incubated organic wastes as amendments in reducing pesticide leaching through soil columns.

    PubMed

    Marín-Benito, J M; Brown, C D; Herrero-Hernández, E; Arienzo, M; Sánchez-Martín, M J; Rodríguez-Cruz, M S

    2013-10-01

    Soil amendment with organic wastes is becoming a widespread management practice since it can effectively solve the problems of uncontrolled waste accumulation and improve soil quality. However, when simultaneously applied with pesticides, organic wastes can significantly modify the environmental behaviour of these compounds. This study evaluated the effect of sewage sludges (SS), grape marc (GM) and spent mushroom substrates (SMS) on the leaching of linuron, diazinon and myclobutanil in packed columns of a sandy soil with low organic matter (OM) content (<1%). Soil plus amendments had been incubated for one month (1 m) or 12 months (12 m). Data from the experimental breakthrough curves (BTCs) were fitted to the one-dimensional transport model CXTFIT 2.1. All three amendments reduced leaching of linuron and myclobutanil relative to unamended soil. SMS was the most effective in reducing leaching of these two compounds independent of whether soil was incubated for 1 m or 12 m. Soil amendments increased retardation coefficients (Rexp) by factors of 3 to 5 for linuron, 2 to 4 for diazinon and 3 to 5 for myclobutanil relative to unamended soil. Leaching of diazinon was relatively little affected by soil amendment compared to the other two compounds and both SS and SMS amendment with 1m incubation resulted in enhanced leaching of diazinon. The leaching data for linuron and myclobutanil were well described by CXTFIT (mean square error, MSE<4.9·10(-7) and MSE<7.0·10(-7), respectively) whereas those of diazinon were less well fitted (MSE<2.1·10(-6)). The BTCs for pesticides were similar in soils incubated for one month or one year, indicating that the effect of amendment on leaching persists over relatively long periods of time. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Bio-augmentation and nutrient amendment decrease concentration of mercury in contaminated soil.

    PubMed

    Mahbub, Khandaker Rayhan; Krishnan, Kannan; Andrews, Stuart; Venter, Henrietta; Naidu, Ravi; Megharaj, Mallavarapu

    2017-01-15

    Four mercury (Hg) contaminated soils with different pH (7.6, 8.5, 4.2 and 7.02) and total organic carbon contents (2.1, 2.2, 4 and 0.9%) were subjected to bioremediation utilizing a Hg volatilizing bacterial strain Sphingobium SA2 and nutrient amendment. In a field with ~280mg/kgHg, 60% of Hg was removed by bio-augmentation in 7days, and the removal was improved when nutrients were added. Whereas in artificially spiked soils, with ~100mg/kgHg, removal due to bio-augmentation was 33 to 48% in 14days. In the field contaminated soil, nutrient amendment alone without bio-augmentation removed 50% of Hg in 28days. Nutrient amendment also had an impact on Hg remediation in the spiked soils, but the best results were obtained when the strain and nutrients both were applied. The development of longer root lengths from lettuce and cucumber seeds grown in the remediated soils confirmed that the soil quality improved after bioremediation. This study clearly demonstrates the potential of Hg-reducing bacteria in remediation of Hg-contaminated soils. However, it is desirable to trap the volatilized Hg for enhanced bioremediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. The Effect of paper mill waste and sewage sludge amendments on soil organic matter

    NASA Astrophysics Data System (ADS)

    Méndez, Ana; Barriga, Sandra; Guerrero, Francisca; Gascó, Gabriel

    2013-04-01

    In general, Mediterranean soils have low organic matter content, due to the climate characteristics of this region and inadequate land management. Traditionally, organic wastes such as manure are used as amendment in order to improve the soil quality, increasing soil fertility by the accumulation of nitrogen, phosphorus and other plant nutrients in the soil. In the last decade, other anthropogenic organic wastes such as sewage sludge or paper waste materials have been studied as soil amendments to improve physical, chemical and biological properties of soils. The objective of the present work was to study the influence of waste from a paper mill and sewage sludge amendments on soil organic matter. For this reason, soil organic matter evolution was studied using thermogravimetric analysis (TGA), the derivative (dTG) and differential thermal analysis (DTA). Thermal analytical techniques have the advantage of using full samples without pre-treatments and have been extensively used to study the evolution of organic matter in soils, to evaluate composting process or to study the evolution of organic matter of growing media.

  5. The influence of organic amendments on soil aggregate stability from semiarid sites

    NASA Astrophysics Data System (ADS)

    Hueso Gonzalez, Paloma; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

    2016-04-01

    Restoring the native vegetation is the most effective way to regenerate soil health. Under these conditions, vegetation cover in areas having degraded soils may be better sustained if the soil is amended with an external source of organic matter. The addition of organic materials to soils also increases infiltration rates and reduces erosion rates; these factors contribute to an available water increment and a successful and sustainable land management. The goal of this study was to analyze the effect of various organic amendments on the aggregate stability of soils in afforested plots. An experimental paired-plot layout was established in southern of Spain (homogeneous slope gradient: 7.5%; aspect: N170). Five amendments were applied in an experimental set of plots: straw mulching; mulch with chipped branches of Aleppo Pine (Pinus halepensis L.); TerraCotten hydroabsobent polymers; sewage sludge; sheep manure and control. Plots were afforested following the same spatial pattern, and amendments were mixed with the soil at the rate 10 Mg ha-1. The vegetation was planted in a grid pattern with 0.5 m between plants in each plot. During the afforestation process the soil was tilled to 25 cm depth from the surface. Soil from the afforested plots was sampled in: i) 6 months post-afforestation; ii) 12 months post-afforestation; iii) 18 months post-afforestation; and iv) 24 months post-afforestation. The sampling strategy for each plot involved collection of 4 disturbed soil samples taken from the surface (0-10 cm depth). The stability of aggregates was measured by wet-sieving. Regarding to soil aggregate stability, the percentage of stable aggregates has increased slightly in all the treatments in relation to control. Specifically, the differences were recorded in the fraction of macroaggregates (≥ 0.250 mm). The largest increases have been associated with straw mulch, pinus mulch and sludge. Similar results have been registered for the soil organic carbon content

  6. Long-term manure amendments reduced soil aggregate stability via redistribution of the glomalin-related soil protein in macroaggregates

    PubMed Central

    Xie, Hongtu; Li, Jianwei; Zhang, Bin; Wang, Lianfeng; Wang, Jingkuan; He, Hongbo; Zhang, Xudong

    2015-01-01

    Glomalin-related soil protein (GRSP) contributes to the formation and maintenance of soil aggregates, it is however remains unclear whether long-term intensive manure amendments alter soil aggregates stability and whether GRSP regulates these changes. Based on a three-decade long fertilization experiment in northeast China, this study examined the impact of long-term manure input on soil organic carbon (SOC), total and easily extractable GRSP (GRSPt and GRSPe) and their respective allocations in four soil aggregates (>2000 μm; 2000–250 μm; 250–53 μm; and <53 μm). The treatments include no fertilization (CK), low and high manure amendment (M1, M2), chemical nitrogen, phosphorus and potassium fertilizers (NPK), and combined manure and chemical fertilizers (NPKM1, NPKM2). Though SOC, GRSPe and GRSPt in soil and SOC in each aggregate generally increased with increasing manure input, GRSPt and GRSPe in each aggregate showed varying changes with manure input. Both GRSP in macroaggregates (2000–250 μm) were significantly higher under low manure input, a pattern consistent with changes in soil aggregate stability. Constituting 38~49% of soil mass, macroaggregates likely contributed to the nonlinear changes of aggregate stability under manure amendments. The regulatory process of GRSP allocations in soil aggregates has important implications for manure management under intensive agriculture. PMID:26423355

  7. Elemental transport and distribution in soils amended with incinerated sewage sludge.

    PubMed

    Paramasivam, S; Sajwan, K S; Alva, A K; VanClief, D; Hostler, K H

    2003-05-01

    Sewage sludge (SS) is the major solid waste of sewage and wastewater treatment plants in cities around the world. Even though treated effluent water from wastewater treatment plants are utilized for irrigation, disposal of sewage sludge is becoming a serious problem. This is due to its high content of certain heavy metals still posing threat of accumulation in plants and groundwater contamination when it is used as soil amendment or disposed in landfills. Water treatment plants incinerate the dewatered activated sewage sludge (ISS) and dissolve the ash in water to store in ash ponds for long-term storage (WISS). A study was undertaken to evaluate the transport and leaching potential of various elements and their distribution within soil columns amended with various rates of ISS. Results of this study indicates that ISS from wastewater treatment plants can be used as soil amendment on agricultural lands at low to medium rates (< or = 100 Mg ha(-1)) without causing potential loading of metals into groundwater.

  8. Extractability and Bioavailability of Pb and As in Historically Contaminated Orchard Soil: Effects of Compost Amendments

    PubMed Central

    Fleming, Margaret; Yiping, Tai; Ping, Zhuang; McBride, Murray B.

    2015-01-01

    The availability of Pb and As in an historically contaminated orchard soil, after amendment with compost and aging in the field, was determined by single-step chemical extraction with 1.0 M ammonium acetate at pH 4.8, sequential extraction using the modified BCR test, and a redworm bioassay in the laboratory. The efficiency of soil Pb extraction by ammonium acetate was greater at higher total soil Pb but was reduced by compost amendment. Conversely, the extraction efficiency of total soil As increased with compost amendment, but was not sensitive to total soil As. The redworm bioassay indicated Pb (but not As) bioavailability to be reduced by soil amendment with compost, a result consistent with the ammonium acetate extraction test but not reflected in modified BCR test. Electron microprobe studies of the orchard soil revealed Pb and As to be spatially associated in discrete particles along with phosphorus and iron. PMID:23474982

  9. SITE Technology Capsule. Demonstration of Rocky Mountain Remediation Services Soil Amendment

    EPA Science Inventory

    This report briefly summarizes the Rocky Mountain Remediation Services treatment technology demonstration of a soil amendment process for lead contaminated soil at Roseville, OH. The evaluation included leaching, bioavailability, geotechnical, and geochemical methods.

  10. Do plant-based amendments improve soil physiochemical and microbiological properties and plant growth in dryland ecosystems?

    NASA Astrophysics Data System (ADS)

    Kneller, Tayla; Harris, Richard; Muñoz-Rojas, Miriam

    2017-04-01

    Background Land intensive practices including mining have contributed to the degradation of landscapes globally. Current challenges in post-mine restoration revolve around the use of substrates poor in organic materials (e.g. overburden and waste rock) and lack of original topsoil which may result in poor seedling recruitment and in later stages in soil nutrient deficiency, metal toxicity, decreased microbial activity and high salinity (Bateman et al., 2016; Muñoz-Rojas et al., 2016). Despite continuous efforts and advances we have not proportionally advanced our capability to successfully restore these landscapes following mining. Recent attempts to improve plant establishment in arid zone restoration programs have included the application of plant based amendments to soil profiles. This approach usually aims to accelerate soil reconstruction via improvement of soil aggregate stability and increase of soil organic carbon, and water holding capacity. Whilst a significant amount of recent research has focused on the application of such amendments, studies on the potential application of plant based materials to recover soil functionality and re-establish plant communities in post-mined landscapes in arid regions are limited. Here we will discuss our work investigating the application of a plant based amendment on soil substrates commonly used in post mining restoration in the Pilbara region, Western Australia. Methodology The study was conducted in a glasshouse facility where environmental conditions were continuously monitored. Using two growth materials (topsoil and waste rock) and a plant based amendment (dry biomass of the most common grass in the Pilbara, Triodia wiseana) five different treatments were tested. Treatments consisted of control soil treatments (topsoil, waste and a mixture of the former soil types (mixture)) and two amended soil treatments (waste amended and mixture amended). Additionally, three different vegetation communities were studies

  11. DETERMINING SPECIATION OF PB IN PHOSPHATE AMENDED SOILS: METHOD LIMITATIONS

    EPA Science Inventory

    Determining the effectiveness of in-situ immobilization for P-amended, Pb-contaminated soils has typically relied on non-spectroscopic methods that in recent years have come under scrutiny due to technical and unforeseen error issues. In this study, we analyzed 18 soil samples vi...

  12. Ammonia oxidation-dependent growth of group I.1b Thaumarchaeota in acidic red soil microcosms.

    PubMed

    Wu, Yucheng; Conrad, Ralf

    2014-07-01

    Accumulating evidence suggests that Thaumarchaeota may control nitrification in acidic soils. However, the composition of the thaumarchaeotal communities and their functioning is not well known. Therefore, we studied nitrification activity in relation to abundance and composition of Thaumarchaeota in an acidic red soil from China, using microcosms incubated with and without cellulose amendment. Cellulose was selected to simulate the input of crop residues used to increase soil fertility by local farming. Accumulation of NO3-(-N) was correlated with the growth of Thaumarchaeota as determined by qPCR of 16S rRNA and ammonia monooxygenase (amoA) genes. Both nitrification activity and thaumarchaeotal growth were inhibited by acetylene. They were also inhibited by cellulose amendment, possibly due to the depletion of ammonium by enhanced heterotrophic assimilation. These results indicated that growth of Thaumarchaeota was dependent on ammonia oxidation. The thaumarchaeotal 16S rRNA gene sequences in the red soil were dominated by a clade related to soil fosmid clone 29i4 within the group I.1b, which is widely distributed but so far uncultured. The archaeal amoA sequences were mainly related to the Nitrososphaera sister cluster. These observations suggest that fosmid clone 29i4 and Nitrososphaera sister cluster represent the same group of Thaumarchaeota and dominate ammonia oxidation in acidic red soil. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  13. Arsenic uptake by lettuce from As-contaminated soil remediated with Pteris vittata and organic amendment.

    PubMed

    de Oliveira, Letuzia M; Suchismita, Das; Gress, Julia; Rathinasabapathi, Bala; Chen, Yanshan; Ma, Lena Q

    2017-06-01

    Leaching of inorganic arsenic (As) from chromated copper arsenate (CCA)-treated wood may elevate soil As levels. Thus, an environmental concern arises regarding As accumulation in vegetables grown in these soils. In this study, a greenhouse experiment was conducted to investigate the ability of As-hyperaccumulator P. vittata and organic amendments in reducing As uptake by lettuce (Lactuca sativa) from a soil contaminated from CCA-treated wood (63.9 mg kg -1 As). P. vittata was grown for 150 d in a CCA-contaminated soil amended with biochar, activated carbon or coffee grounds at 1%, followed by lettuce for another 55 d. After harvest, plant biomass and As concentrations in plant and soil were determined. The presence of P. vittata reduced As content in lettuce by 21% from 27.3 to 21.5 mg kg -1 while amendment further reduced As in lettuce by 5.6-18%, with activated C being most effective. Our data showed that both P. vittata and organic amendments were effective in reducing As concentration in lettuce. Though no health-based standard for As in vegetables exists in USA, care should be taken when growing lettuce in contaminated soils. Our data showed that application of organic amendments with P. vittata reduced As hazards in CCA-contaminated soils. Published by Elsevier Ltd.

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

    NASA Astrophysics Data System (ADS)

    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

  15. Effect of dairy manure rate and the stabilization time of amended soils on atrazine degradation.

    PubMed

    Aguilera, Paula; Briceño, Gabriela; Candia, Maribel; Mora, Maria de la Luz; Demanet, Rolando; Palma, Graciela

    2009-10-01

    The application rate of liquid cow manure (LCM) in the field and the stabilization time of amended soils before application of pre-plant herbicides are factors that determine their efficiency. This study includes evaluation of residual atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) in soil and amended soils with equivalent rate of 100,000; 200,000; and 300,000 L ha(-1) of LCM and the effect of pre-incubation time of amended soils on atrazine degradation. The study was carried out under controlled conditions using an Andisol with previous historical application of atrazine. The respiratory activity and fluorescein diacetate (FDA) studies indicated that the time necessary for stabilization of amended soils is over 20-30 d. During the measurement of respiratory and FDA activity, no significant differences were observed when atrazine was applied. The half-life of atrazine ranged from 5 to 8d and the relative distribution of degradation products seem to be affected by the application of LCM. The pre-incubation time of amended soil and LCM dose would not affect atrazine degradation rate, when the soil has a history of herbicide application. However, repeated applications of LCM in a long period of time could change the soil pH and increase the content of dissolved organic carbon (DOC) which could further contribute to a faster degradation of atrazine. Both effects would reduce the effectiveness of atrazine in weed control.

  16. Behaviors of heavy metals (Cd, Cu, Ni, Pb and Zn) in soil amended with composts.

    PubMed

    Gusiatin, Zygmunt Mariusz; Kulikowska, Dorota

    2016-09-01

    This study investigated how amendment with sewage sludge compost of different maturation times (3, 6, 12 months) affected metal (Cd, Cu, Ni, Pb, Zn) bioavailability, fractionation and redistribution in highly contaminated sandy clay soil. Metal transformations during long-term soil stabilization (35 months) were determined. In the contaminated soil, Cd, Ni and Zn were predominately in the exchangeable and reducible fractions, Pb in the reducible fraction and Cu in the reducible, exchangeable and oxidizable fractions. All composts decreased the bioavailability of Cd, Ni and Zn for up to 24 months, which indicates that cyclic amendment with compost is necessary. The bioavailability of Pb and Cu was not affected by compost amendment. Based on the reduced partition index (IR), metal stability in amended soil after 35 months of stabilization was in the following order: Cu > Ni = Pb > Zn > Cd. All composts were more effective in decreasing Cd, Ni and Zn bioavailability than in redistributing the metals, and increasing Cu redistribution more than that of Pb. Thus, sewage sludge compost of as little as 3 months maturation can be used for cyclic amendment of multi-metal-contaminated soil.

  17. Low occurrence of Pseudomonas aeruginosa in agricultural soils with and without organic amendment

    PubMed Central

    Deredjian, Amélie; Colinon, Céline; Hien, Edmond; Brothier, Elisabeth; Youenou, Benjamin; Cournoyer, Benoit; Dequiedt, Samuel; Hartmann, Alain; Jolivet, Claudy; Houot, Sabine; Ranjard, Lionel; Saby, Nicolas P. A.; Nazaret, Sylvie

    2014-01-01

    The occurrence of Pseudomonas aeruginosa was monitored at a broad spatial scale in French agricultural soils, from various soil types and under various land uses to evaluate the ability of soil to be a natural habitat for that species. To appreciate the impact of agricultural practices on the potential dispersion of P. aeruginosa, we further investigated the impact of organic amendment at experimental sites in France and Burkina Faso. A real-time quantitative PCR (qPCR) approach was used to analyze a set of 380 samples selected within the French RMQS (“Réseau de Mesures de la Qualité des Sols”) soil library. In parallel, a culture-dependent approach was tested on a subset of samples. The results showed that P. aeruginosa was very rarely detected suggesting a sporadic presence of this bacterium in soils from France and Burkina Faso, whatever the structural and physico-chemical characteristics or climate. When we analyzed the impact of organic amendment on the prevalence of P. aeruginosa, we found that even if it was detectable in various manures (at levels from 103 to 105 CFU or DNA targets (g drywt)−1 of sample), it was hardly ever detected in the corresponding soils, which raises questions about its survival. The only case reports were from a vineyard soil amended with a compost of mushroom manure in Burgundy, and a few samples from two fields amended with raw urban wastes in the sub-urban area of Ouagadougou, Burkina Faso. In these soils the levels of culturable cells were below 10 CFU (g drywt)−1. PMID:24809025

  18. Effects of Short-Term Biosolarization Using Mature Compost and Industrial Tomato Waste Amendments on the Generation and Persistence of Biocidal Soil Conditions and Subsequent Tomato Growth.

    PubMed

    Achmon, Yigal; Sade, Nir; Wilhelmi, María Del Mar Rubio; Fernández-Bayo, Jesus D; Harrold, Duff R; Stapleton, James J; VanderGheynst, Jean S; Blumwald, Eduardo; Simmons, Christopher W

    2018-06-06

    Conventional solarization and biosolarization with mature compost and tomato processing residue amendments were compared with respect to generation of pesticidal conditions and tomato ( Solanum lycopersicum L.) plant growth in treated soils. Soil oxygen depletion was examined as a response that has previously not been measured across multiple depths during biosolarization. For biosolarized soil, volatile fatty acids were found to accumulate concurrent with oxygen depletion, and the magnitude of these changes varied by soil depth. Two consecutive years of experimentation showed varying dissipation of volatile fatty acids from biosolarized soils post-treatment. When residual volatile fatty acids were detected in the biosolarized soil, fruit yield did not significantly differ from plants grown in solarized soil. However, when there was no residual volatile fatty acids in the soil at the time of planting, plants grown in biosolarized soil showed a significantly greater vegetation amount, fruit quantity, and fruit ripening than those of plants grown in solarized soil.

  19. Combination of biochar amendment and phytoremediation for hydrocarbon removal in petroleum-contaminated soil.

    PubMed

    Han, Tao; Zhao, Zhipeng; Bartlam, Mark; Wang, Yingying

    2016-11-01

    Remediation of soils contaminated with petroleum is a challenging task. Four different bioremediation strategies, including natural attenuation, biochar amendment, phytoremediation with ryegrass, and a combination of biochar and ryegrass, were investigated with greenhouse pot experiments over a 90-day period. The results showed that planting ryegrass in soil can significantly improve the removal rate of total petroleum hydrocarbons (TPHs) and the number of microorganisms. Within TPHs, the removal rate of total n-alkanes (45.83 %) was higher than that of polycyclic aromatic hydrocarbons (30.34 %). The amendment of biochar did not result in significant improvement of TPH removal. In contrast, it showed a clear negative impact on the growth of ryegrass and the removal of TPHs by ryegrass. The removal rate of TPHs was significantly lower after the amendment of biochar. The results indicated that planting ryegrass is an effective remediation strategy, while the amendment of biochar may not be suitable for the phytoremediation of soil contaminated with petroleum hydrocarbons.

  20. Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.

    PubMed

    Li, Xiaojing; Wang, Xin; Ren, Zhiyong Jason; Zhang, Yueyong; Li, Nan; Zhou, Qixing

    2015-12-01

    Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Revegetation of extremely acid mine soils based on aided phytostabilization: A case study from southern China.

    PubMed

    Yang, Sheng-Xiang; Liao, Bin; Yang, Zhi-Hui; Chai, Li-Yuan; Li, Jin-Tian

    2016-08-15

    Acidification is a major constraint for revegetation of sulphidic metal-contaminated soils, as exemplified by the limited literature reporting the successful phytostabilization of mine soils associated with pH<3 and high acidification potential. In this study, a combination of ameliorants (lime and chicken manure) and five acid-tolerant plant species has been employed in order to establish a self-sustaining vegetation cover on an extremely acid (pH<3) polymetallic pyritic mine waste heap in southern China exhibiting high acidification potential. The results from the first two-year data showed that the addition of the amendments and the establishment of a plant cover were effective in preventing soil acidification. Net acid-generating potential of the mine soil decreased steadily, whilst pH and acid neutralization capacity increased over time. All the five acid-tolerant plants colonized successfully in the acidic metal-contaminated soil and developed a good vegetation cover within six months, and subsequent vegetation development enhanced organic matter accumulation and nutrient element status in the mine soil. The two-year remediation program performed on this extremely acid metalliferous soil indicated that aided phytostabilization can be a practical and effective restoration strategy for such extremely acid mine soils. Copyright © 2016. Published by Elsevier B.V.

  2. Effects of Biochar Amendment on Soil Properties and Soil Carbon Sequestration

    NASA Astrophysics Data System (ADS)

    Zhang, R.; Zhu, S.

    2015-12-01

    Biochar addition to soils potentially affects various soil properties and soil carbon sequestration, and these effects are dependent on biochars derived from different feedstock materials and pyrolysis processes. The objective of this study was to investigate the effects of amendment of different biochars on soil physical and biological properties as well as soil carbon sequestration. Biochars were produced with dairy manure and woodchip at temperatures of 300, 500, and 700°C, respectively. Each biochar was mixed at 5% (w/w) with a forest soil and the mixture was incubated for 180 days, during which soil physical and biological properties, and soil respiration rates were measured. Results showed that the biochar addition significantly enhanced the formation of soil macroaggregates at the early incubation time. The biochar application significantly reduced soil bulk density, increased the amount of soil organic matter, and stimulated microbial activity and soil respiration rates at the early incubation stage. Biochar applications improved water retention capacity, with stronger effects by biochars produced at higher pyrolysis temperatures. At the same suction, the soil with woodchip biochars possessed higher water content than with the dairy manure biochars. Biochar addition significantly affected the soil physical and biological properties, which resulted in different soil carbon mineralization rates and the amount of soil carbon storage.

  3. Organic Amendments to Avocado Crops Induce Suppressiveness and Influence the Composition and Activity of Soil Microbial Communities

    PubMed Central

    Bonilla, Nuria; Vida, Carmen; Martínez-Alonso, Maira; Landa, Blanca B.; Gaju, Nuria; Cazorla, Francisco M.

    2015-01-01

    One of the main avocado diseases in southern Spain is white root rot caused by the fungus Rosellinia necatrix Prill. The use of organic soil amendments to enhance the suppressiveness of natural soil is an inviting approach that has successfully controlled other soilborne pathogens. This study tested the suppressive capacity of different organic amendments against R. necatrix and analyzed their effects on soil microbial communities and enzymatic activities. Two-year-old avocado trees were grown in soil treated with composted organic amendments and then used for inoculation assays. All of the organic treatments reduced disease development in comparison to unamended control soil, especially yard waste (YW) and almond shells (AS). The YW had a strong effect on microbial communities in bulk soil and produced larger population levels and diversity, higher hydrolytic activity and strong changes in the bacterial community composition of bulk soil, suggesting a mechanism of general suppression. Amendment with AS induced more subtle changes in bacterial community composition and specific enzymatic activities, with the strongest effects observed in the rhizosphere. Even if the effect was not strong, the changes caused by AS in bulk soil microbiota were related to the direct inhibition of R. necatrix by this amendment, most likely being connected to specific populations able to recolonize conducive soil after pasteurization. All of the organic amendments assayed in this study were able to suppress white root rot, although their suppressiveness appears to be mediated differentially. PMID:25769825

  4. Biochar amendment changes jasmonic acid levels in two rice varieties and alters their resistance to herbivory

    PubMed Central

    Shahzad, Raheem; Hamayun, Muhammad; Asaf, Sajjad; Khan, Abdul Latif; Kang, Sang-Mo; Yun, Sopheap; Kim, Kyung-Min; Lee, In-Jung

    2018-01-01

    Biochar addition to soil not only sequesters carbon for the long-term but enhances agricultural productivity. Several well-known benefits arise from biochar amendment, including constant provision of nutrients, increased soil moisture retention, decreased soil bulk density, and sometimes the induction of systemic resistance against foliar and soil borne plant pathogens. However, no research has investigated the potential of biochar to increase resistance against herbivory. The white-backed plant hopper (WBPH) (Sogatella furcifera Horváth) is a serious agricultural pest that targets rice (Oryza sativa L.), a staple crop that feeds half of the world’s human population. Therefore, we investigated the (1) optimization of biochar amendment levels for two rice varieties (‘Cheongcheong’ and ‘Nagdong’) and (2) subsequent effects of different biochar amendments on resistance and susceptibility of these two varieties to WBPH infestation. Initial screening results for the optimization level revealed that the application of biochar 10% (w/w) to the rooting media significantly improved plant physiological characteristics of both rice varieties. However, levels of biochar amendment, mainly 1, 2, 3, and 20%, resulted in negative effects on plant growth characteristics. Cheongcheong and Nagdong rice plants grown with the optimum biochar level showed contrasting reactions to WBPH infestation. Specifically, biochar application significantly increased plant growth characteristics of Nagdong when exposed to WBPH infestation and significantly decreased these characteristics in Cheongcheong. The amount of WBPH-induced damage to plants was significantly lower and higher in Nagdong and Cheongcheong, respectively, compared to that in the controls. Higher levels of jasmonic acid caused by the biochar priming effect could have accumulated in response to WBPH infestation, resulting in a maladaptive response to stress, negatively affecting growth and resistance to WBPH in

  5. Biochar amendment changes jasmonic acid levels in two rice varieties and alters their resistance to herbivory.

    PubMed

    Waqas, Muhammad; Shahzad, Raheem; Hamayun, Muhammad; Asaf, Sajjad; Khan, Abdul Latif; Kang, Sang-Mo; Yun, Sopheap; Kim, Kyung-Min; Lee, In-Jung

    2018-01-01

    Biochar addition to soil not only sequesters carbon for the long-term but enhances agricultural productivity. Several well-known benefits arise from biochar amendment, including constant provision of nutrients, increased soil moisture retention, decreased soil bulk density, and sometimes the induction of systemic resistance against foliar and soil borne plant pathogens. However, no research has investigated the potential of biochar to increase resistance against herbivory. The white-backed plant hopper (WBPH) (Sogatella furcifera Horváth) is a serious agricultural pest that targets rice (Oryza sativa L.), a staple crop that feeds half of the world's human population. Therefore, we investigated the (1) optimization of biochar amendment levels for two rice varieties ('Cheongcheong' and 'Nagdong') and (2) subsequent effects of different biochar amendments on resistance and susceptibility of these two varieties to WBPH infestation. Initial screening results for the optimization level revealed that the application of biochar 10% (w/w) to the rooting media significantly improved plant physiological characteristics of both rice varieties. However, levels of biochar amendment, mainly 1, 2, 3, and 20%, resulted in negative effects on plant growth characteristics. Cheongcheong and Nagdong rice plants grown with the optimum biochar level showed contrasting reactions to WBPH infestation. Specifically, biochar application significantly increased plant growth characteristics of Nagdong when exposed to WBPH infestation and significantly decreased these characteristics in Cheongcheong. The amount of WBPH-induced damage to plants was significantly lower and higher in Nagdong and Cheongcheong, respectively, compared to that in the controls. Higher levels of jasmonic acid caused by the biochar priming effect could have accumulated in response to WBPH infestation, resulting in a maladaptive response to stress, negatively affecting growth and resistance to WBPH in Cheongcheong. This

  6. Amendments and mulches improve the biological quality of soils degraded by mining activities in SE Spain

    NASA Astrophysics Data System (ADS)

    Luna Ramos, Lourdes; Miralles Mellado, Isabel; Hernández Fernández, María Teresa; García Izquierdo, Carlos; Solé Benet, Albert

    2014-05-01

    Mining and quarrying activities generate negative visual impacts in the landscape and a loss of environmental quality. Substrate properties at the end of mining are in general not suitable for plant growth, even native ones. In an experimental soil restoration in limestone quarries from Sierra de Gádor (Almería), SE Spain, the effect of organic amendment (sewage sludge, compost from the organic fraction of domestic waste or non-amendment) combined or not with two different kind of mulches (fine gravel, chopped forest residue) was tested by triplicate in 5 x 5 m plots with the aim to improve soil/substrate properties and to reduce evaporation and erosion. In each experimental plot 75 native plants (Stipa tenacissima, Anthyllis terniflora and Anthyllis cytisoides) were planted. Effects of adding organic amendments and mulches on some soil microbiological and biochemical parameters (microbial biomass carbon, basal respiration and different enzymatic activities, such as dehydrogenase, phosphatase, β-glucosidase and urease) were analyzed 5 years after the start of the experiment. Vegetation growth was also monitored. The two-way ANOVA, using as factors amendment and mulch, showed a significant positive influence of organic amendments on microbial biomass (Cmic), basal respiration and some enzymatic activities related to the cycles of C and N. The highest values of these parameters were obtained with compost. The influence of the mulch factor and its interactions with the amendment factor on the measured variables did not follow a clear trend with respect the measured parameters. Mulching did not improved significantly (p<0.05) the positive effect of organic amendments on Cmic although Cmic values increased with the incorporation of "forest chopped residue" and decreased with gravel incorporation. In general, both type of mulch decreased or have no effect on the microbial activity detected in the amended soils, with the only exception of the forest chopped residue

  7. Mechanisms of distinct activated carbon and biochar amendment effects on petroleum vapour biofiltration in soil.

    PubMed

    Bushnaf, Khaled M; Mangse, George; Meynet, Paola; Davenport, Russell J; Cirpka, Olaf A; Werner, David

    2017-10-18

    We studied the effects of two percent by weight activated carbon versus biochar amendments in 93 cm long sand columns on the biofiltration of petroleum vapours released by a non-aqueous phase liquid (NAPL) source. Activated carbon greatly enhanced, whereas biochar slightly reduced, the biofiltration of volatile petroleum hydrocarbons (VPHs) over 430 days. Sorbent amendment benefitted the VPH biofiltration by retarding breakthrough during the biodegradation lag phase. Subsequently, sorbent amendment briefly reduced the mineralization of petroleum hydrocarbons by limiting their bioavailability. During the last and longest study period, when conditions became less supportive of microbial growth, because of inorganic nutrient scarcity, the sorbents again improved the pollution attenuation by preventing the degrading microorganisms from being overloaded with VPHs. A 16S rRNA gene based analysis showed sorbent amendment effects on soil microbial communities. Nocardioidaceae benefitted the most from petroleum hydrocarbons in activated carbon amended soil, whereas Pseudomonadacea predominated in unamended soil. Whilst the degrading microorganisms were overloaded with VPHs in the unamended soil, the reduced mobility and bioavailability of VPHs in the activated carbon amended soil led to the emergence of communities with higher specific substrate affinity, which removed bioavailable VPHs effectively at low concentrations. A numerical pollutant fate model reproduced these experimental observations by considering sorption effects on the pollutant migration and bioavailability for growth of VPH degrading biomass, which is limited by a maximum soil biomass carrying capacity. Activated carbon was a much stronger sorbent for VPHs than biochar, which explained the diverging effects of the two sorbents in this study.

  8. Improving the mining soil quality for a vegetation cover after addition of sewage sludges: inorganic ions and low-molecular-weight organic acids in the soil solution.

    PubMed

    Peña, Aránzazu; Mingorance, Mª Dolores; Guzmán-Carrizosa, Ignacio; Fernández-Espinosa, Antonio J

    2015-03-01

    We assessed the effects of applying stabilized sewage sludge (SSL) and composted sewage sludge (CLV), at 5 and 10% to an acid mining soil. Limed soil (NCL) amended or not with SSL and CLV was incubated for 47 days. We studied the cations and organic and inorganic anions in the soil solution by means of ion chromatography. Liming led to big increases in Ca(2+) and SO4(2-) and to significant decreases in K(+), Mg(2+), NH4(+) and NO3(-). Addition of both organic amendments increased some cations (NH4(+), K(+), Mg(2+), Na(+)) and anions (Cl(-), NO3(-) only with CLV and PO4(3-) only with SSL) and provided a greater amount of low-molecular-weight organic acids (LMWOAs) (SSL more than CLV). Incubation led to decreases in all cations, particularly remarkable for Ca(2+) and Mg(2+) in SSL-10. A decrease in NH4(+) was associated with variations in NO2(-) and NO3(-) resulting from nitrification reactions. During incubation the LMWOAs content tended to decrease similarly to the cations, especially in SSL-10. Chemometric tools revealed a clear discrimination between SSL, CLV and NCL. Furthermore, treatment effects depended upon dose, mainly in SSL. Amendment nature and dose affect the quality of a mining soil and improve conditions for plant establishment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Efficacy of Organic Soil Amendments for Management of Heterodera glycines in Greenhouse Experiments.

    PubMed

    Grabau, Zane J; Chen, Senyu

    2014-09-01

    In a repeated greenhouse experiment, organic soil amendments were screened for effects on population density of soybean cyst nematode (SCN), Heterodera glycines, and soybean growth. Ten amendments at various rates were tested: fresh plant material of field pennycress, marigold, spring camelina, and Cuphea; condensed distiller's solubles (CDS), ash of combusted CDS, ash of combusted turkey manure (TMA), marigold powder, canola meal, and pennycress seed powder. Soybeans were grown for 70 d in field soil with amendments and SCN eggs incorporated at planting. At 40 d after planting (DAP), many amendments reduced SCN egg population density, but some also reduced plant height. Cuphea plant at application rate of 2.9% (amendment:soil, w:w, same below), marigold plant at 2.9%, pennycress seed powder at 0.5%, canola meal at 1%, and CDS at 4.3% were effective against SCN with population reductions of 35.2%, 46.6%, 46.7%, 73.2%, and 73.3% compared with control, respectively. For Experiment 1 at 70 DAP, canola meal at 1% and pennycress seed powder at 0.5% reduced SCN population density 70% and 54%, respectively. CDS at 4.3%, ash of CDS at 0.2%, and TMA at 1% increased dry plant mass whereas CDS at 4.3% and pennycress seed powder at 0.1% reduced plant height. For Experiment 2 at 70 DAP, amendments did not affect SCN population nor plant growth. In summary, some amendments were effective for SCN management, but phytoxicity was a concern.

  10. The potential of residues of furfural and biogas as calcareous soil amendments for corn seed production.

    PubMed

    Zhao, Yunchen; Yan, Zhibin; Qin, Jiahai; Ma, Zhijun; Zhang, Youfu; Zhang, Li

    2016-04-01

    Intensive corn seed production in Northwest of China produced large amounts of furfural residues, which represents higher treatment cost and environmental issue. The broad calcareous soils in the Northwest of China exhibit low organic matter content and high pH, which led to lower fertility and lower productivity. Recycling furfural residues as soil organic and nutrient amendment might be a promising agricultural practice to calcareous soils. A 3-year field study was conducted to evaluate the effects of furfural as a soil amendment on corn seed production on calcareous soil with compared to biogas residues. Soil physical-chemical properties, soil enzyme activities, and soil heavy metal concentrations were assessed in the last year after the last application. Corn yield was determined in each year. Furfural residue amendments significantly decreased soil pH and soil bulk density. Furfural residues combined with commercial fertilizers resulted in the greater cumulative on soil organic matter, total phosphorus, available phosphorus, available potassium, and cation exchange capacity than that of biogas residue. Simultaneously, urease, invertase, catalase, and alkaline phosphatase increased even at the higher furfural application rates. Maize seed yield increased even with lower furfural residue application rates. Furfural residues resulted in lower Zn concentration and higher Cd concentration than that of biogas residues. Amendment of furfural residues led to higher soil electrical conductivity (EC) than that of biogas residues. The addition of furfural residues to maize seed production may be considered to be a good strategy for recycling the waste, converting it into a potential resource as organic amendment in arid and semi-arid calcareous soils, and may help to reduce the use of mineral chemical fertilizers in these soils. However, the impact of its application on soil health needs to be established in long-term basis.

  11. Metolachlor sorption and degradation in soil amended with fresh and aged biochar

    USDA-ARS?s Scientific Manuscript database

    Addition of organic amendments such as biochar to soils can influence pesticide sorption-desorption processes, and in turn, pesticide availability and biodegradation. Availability is affected by both the physical and chemical properties of soils and pesticides, as well as soil-pesticide contact time...

  12. Interactions of triclosan, gemfibrozil and galaxolide with biosolid-amended soils: Effects of the level and nature of soil organic matter.

    PubMed

    Usyskin, Alla; Bukhanovsky, Nadezhda; Borisover, Mikhail

    2015-11-01

    Triclosan, gemfibrozil and galaxolide, representing acidic and non-ionized hydrophobic organic compounds, are biologically active and can be accumulated during wastewater treatment in sewage sludge. The interactions of these substances with the soils amended by sewage sludge-originating biosolids may control their environmental fate. Therefore, the sorption of three organic compounds was studied in dune sand, loess soil, clay soil and mixtures of these media with three different sewage sludge-originating biosolids that were incubated under aerobic conditions for 6 months. For each compound, 15 sorption isotherms were produced at pH 7.8-8.0. The sorption of triclosan and gemfibrozil on sand-containing sorbents was examined also under acidic conditions. In some soil series, the compound's Freundlich constants (KF) are linearly related to the soil organic carbon (OC) content. Notably, for a given OC content, the sand-containing sorbents tend to demonstrate enhanced interactions with triclosan and galaxolide. This may be related with more hydrophobic and/or less rigid soil organic matter (SOM) as compared with the clay-containing soils, implying indirect effects of minerals. Generally the OC-normalized KF vary among different soil-biosolid combinations which is explained by the differences in the composition and properties of SOM, and is also contributed by the non-zero intercepts of the linear KF upon soil OC dependencies. The negative intercepts suggest that below a certain OC level no considerable organic compound-soil interactions would occur. Interactions of molecular and anionic forms of triclosan with a sand-containing sorbent may be comparable, but interactions involving gemfibrozil molecules could be stronger than interactions involving its anion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Short-term effects of natural and NH4+-enriched chabazite zeolitite amendments to soil microbial biomass

    NASA Astrophysics Data System (ADS)

    Ferretti, Giacomo; Keiblinger, Katharina Maria; Di Giuseppe, Dario; Faccini, Barbara; Colombani, Nicolò; Zechmeister-Boltenstern, Sophie; Coltorti, Massimo; Mastrocicco, Micòl

    2017-04-01

    Natural zeolite-bearing rocks (zeolitites) are known to be a suitable material for agricultural purposes by improving soil physicochemical properties and nitrogen use efficiency (NUE). However, little is known about their effects on soil microbial biomass. Aim of this work is to evaluate short-term effects of different chabazite-zeolitite amendments on soil microbial biomass (and activity). To this purpose a silty-clay agricultural soil was amended in three different ways, by the addition of 5 and 15 wt% of natural chabazite zeolitites (NZ) and 10 wt% of NH4+-enriched chabazite zeolitites (CZ). Soil pH, water content, dissolved organic carbon (C), total dissolved N, NH4+, NO3-, NO2-, microbial biomass C and N and ergosterol were periodically measured over a time course of 16 days in a laboratory incubation experiment. In order to verify the immobilization of N derived from CZ into microbial biomass, the δ15N signature of microorganisms was evaluated by the Extraction-Fumigation-Extraction method followed by EA-IRMS analysis. This latter investigation was possible because zeolitites were enriched with NH4+ derived from pig-slurry, which have a very high 15N natural abundance that allow to trace microbial incorporation. Soil amended with 5 wt% of NZ showed increased ergosterol content as well as microbial C/N ratio starting from day 9 of incubation, suggesting that fungal biomass was probably favored, although the same behavior was not found in the soil amended with 15 wt% of the same material. On the other hand, the NH4+-enriched CZ showed strong interactions with soil microbial biomass N. Isotopic measurements supported microbial assimilation of the N introduced with CZ since the second day of incubation. The high dissolved organic C and microbial biomass N suggested an increase of mineralization and immobilization processes. In addition, in CZ amended soil, microbial biomass N was related to NO3- production over time and inversely related to NH4+, suggesting high

  14. Changes in soil chemistry following wood and grass biochar amendments to an acidic agricultural production soil

    USDA-ARS?s Scientific Manuscript database

    The utility of biochars produced by biomass gasification for remediation of acidic production soils and plant growth in general is not as well known compared to effects from biochars resulting from pyrolysis. Recent characterization of biochar produced from gasification of Kentucky bluegrass (Poa pr...

  15. Humic Acid-Oxidizing, Nitrate-Reducing Bacteria in Agricultural Soils

    PubMed Central

    Van Trump, J. Ian; Wrighton, Kelly C.; Thrash, J. Cameron; Weber, Karrie A.; Andersen, Gary L.; Coates, John D.

    2011-01-01

    ABSTRACT This study demonstrates the prevalence, phylogenetic diversity, and physiology of nitrate-reducing microorganisms capable of utilizing reduced humic acids (HA) as electron donors in agricultural soils. Most probable number (MPN) enumeration of agricultural soils revealed large populations (104 to 106 cells g−1 soil) of microorganisms capable of reducing nitrate while oxidizing the reduced HA analog 2,6-anthrahydroquinone disulfonate (AH2DS) to its corresponding quinone. Nitrate-dependent HA-oxidizing organisms isolated from agricultural soils were phylogenetically diverse and included members of the Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Advective up-flow columns inoculated with corn plot soil and amended with reduced HA and nitrate supported both HA oxidation and enhanced nitrate reduction relative to no-donor or oxidized HA controls. The additional electron donating capacity of reduced HA could reasonably be attributed to the oxidation of reduced functional groups. Subsequent 16S rRNA gene-based high-density oligonucleotide microarray (PhyloChip) indicated that reduced HA columns supported the development of a bacterial community enriched with members of the Acidobacteria, Firmicutes, and Betaproteobacteria relative to the no-donor control and initial inoculum. This study identifies a previously unrecognized role for HA in stimulating denitrification processes in saturated soil systems. Furthermore, this study indicates that reduced humic acids impact soil geochemistry and the indigenous bacterial community composition. PMID:21750120

  16. How Rice (Oryza sativa L.) Responds to Elevated As under Different Si-Rich Soil Amendments.

    PubMed

    Teasley, William A; Limmer, Matthew A; Seyfferth, Angelia L

    2017-09-19

    Several strategies exist to mitigate As impacts on rice and each has its set of trade-offs with respect to yield, inorganic As content in grain, and CH 4 emissions. The addition of Si to paddy soil can decrease As uptake by rice but how rice will respond to elevated As when soil is amended with Si-rich materials is unresolved. Here, we evaluated yield impacts and grain As content and speciation in rice exposed to elevated As in response to different Si-rich soil amendments including rice husk, rice husk ash, and CaSiO 3 in a pot study. We found that As-induced yield losses were alleviated by Husk amendment, partially alleviated by Ash amendment, and not affected by CaSiO 3 amendment. Furthermore, Husk was the only tested Si-amendment to significantly decrease grain As concentrations. Husk amendment was likely effective at decreasing grain As and improving yield because it provided more plant-available Si, particularly during the reproductive and ripening phases. Both Husk and Ash provided K, which also played a role in yield improvement. This study demonstrates that while Si-rich amendments can affect rice uptake of As, the kinetics of Si dissolution and nutrient availability can also affect As uptake and toxicity in rice.

  17. Effect of biochar amendment on tylosin adsorption-desorption and transport in two different soils

    Treesearch

    Chang Yoon Jeong; Jim J. Wang; Syam K. Dodla; Thomas L. Eberhardt; Les Groom

    2012-01-01

    The role of biochar as a soil amendment on the adsorption¨C desorption and transport of tylosin, a macrolide class of veterinary antibiotic, is little known. In this study, batch and column experiments were conducted to investigate the adsorption kinetics and transport of tylosin in forest and agricultural corn field soils amended with hardwood and softwood biochars....

  18. Biochemical activity and chemical-structural properties of soil organic matter after 17 years of amendments with olive-mill pomace co-compost.

    PubMed

    Aranda, V; Macci, C; Peruzzi, E; Masciandaro, G

    2015-01-01

    This study evaluates soil fertility, biochemical activity and the soil's ability to stabilize organic matter after application of composted olive-mill pomace. This organic amendment was applied in two different olive groves in southern Spain having different soil typologies (carbonated and silicic). Olive grove soils after 17 years of organic management with application of olive-mill pomace co-compost were of higher quality than those with conventional management where no co-compost had been applied. The main chemical parameters studied (total organic carbon, total nitrogen, available phosphorus, exchangeable bases, cation exchange capacity, total extractable carbon (TEC), and humic-to-fulvic acids ratio), significantly increased in soils treated with the organic amendment. In particular, the more resistant pool of organic matter (TEC) enhanced by about six and eight fold in carbonated and silicic soils, respectively. Moreover, the amended silicic soils showed the most significant increases in enzyme activities linked to C and P cycles (β-glucosidase twenty-five fold higher and phosphatase seven fold higher). Organic management in both soils induced higher organic matter mineralization, as shown by the higher pyrrole/phenol index (increasing 40% and 150% in carbonated and silicic soils, respectively), and lower furfural/pyrrole index (decreasing 27% and 71% in carbonated and silicic soils, respectively). As a result of mineralization, organic matter incorporated was also more stable as suggested by the trend of the aliphatic/aromatic index (decreasing 36% and 30% in carbonated and silicic soils, respectively). Therefore, management system and soil type are key factors in increasing long-term C stability or sequestration in soils. Thus application of olive-oil extraction by-products to soils could lead to important mid-to -long-term agro-environmental benefits, and be a valuable alternative use for one of the most widespread polluting wastes in the Mediterranean

  19. Organic amendments to avocado crops induce suppressiveness and influence the composition and activity of soil microbial communities.

    PubMed

    Bonilla, Nuria; Vida, Carmen; Martínez-Alonso, Maira; Landa, Blanca B; Gaju, Nuria; Cazorla, Francisco M; de Vicente, Antonio

    2015-05-15

    One of the main avocado diseases in southern Spain is white root rot caused by the fungus Rosellinia necatrix Prill. The use of organic soil amendments to enhance the suppressiveness of natural soil is an inviting approach that has successfully controlled other soilborne pathogens. This study tested the suppressive capacity of different organic amendments against R. necatrix and analyzed their effects on soil microbial communities and enzymatic activities. Two-year-old avocado trees were grown in soil treated with composted organic amendments and then used for inoculation assays. All of the organic treatments reduced disease development in comparison to unamended control soil, especially yard waste (YW) and almond shells (AS). The YW had a strong effect on microbial communities in bulk soil and produced larger population levels and diversity, higher hydrolytic activity and strong changes in the bacterial community composition of bulk soil, suggesting a mechanism of general suppression. Amendment with AS induced more subtle changes in bacterial community composition and specific enzymatic activities, with the strongest effects observed in the rhizosphere. Even if the effect was not strong, the changes caused by AS in bulk soil microbiota were related to the direct inhibition of R. necatrix by this amendment, most likely being connected to specific populations able to recolonize conducive soil after pasteurization. All of the organic amendments assayed in this study were able to suppress white root rot, although their suppressiveness appears to be mediated differentially. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  20. Environmental fate of the fungicide metalaxyl in soil amended with composted olive-mill waste and its biochar: An enantioselective study.

    PubMed

    Gámiz, Beatriz; Pignatello, Joseph J; Cox, Lucía; Hermosín, María C; Celis, Rafael

    2016-01-15

    A large number of pesticides are chiral and reach the environment as mixtures of optical isomers or enantiomers. Agricultural practices can affect differently the environmental fate of the individual enantiomers. We investigated how amending an agricultural soil with composted olive-mill waste (OMWc) or its biochar (BC) at 2% (w:w) affected the sorption, degradation, and leaching of each of the two enantiomers of the chiral fungicide metalaxyl. Sorption of metalaxyl enantiomers was higher on BC (Kd ≈ 145 L kg(-1)) than on OMWc (Kd ≈ 22 L kg(-1)) and was not enantioselective in either case, and followed the order BC-amended>OMWc-amended>unamended soil. Both enantiomers showed greater resistance to desorption from BC-amended soil compared to unamended and OMWc-amended soil. Dissipation studies revealed that the degradation of metalaxyl was more enantioselective (R>S) in unamended and OMWc-amended soil than in BC-amended soil. The leaching of both S- and R-metalaxyl from soil columns was almost completely suppressed after amending the soil with BC and metalaxyl residues remaining in the soil columns were more racemic than those in soil column leachates. Our findings show that addition of BC affected the final enantioselective behavior of metalaxyl in soil indirectly by reducing its bioavailability through sorption, and to a greater extent than OMWc. BC showed high sorption capacity to remove metalaxyl enantiomers from water, immobilize metalaxyl enantiomers in soil, and mitigate the groundwater contamination problems particularly associated with the high leaching potential of the more persistent enantiomer. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Behaviour of oxyfluorfen in soils amended with edaphic biostimulants/biofertilizers obtained from sewage sludge and chicken feathers. Effects on soil biological properties.

    PubMed

    Rodríguez-Morgado, Bruno; Gómez, Isidoro; Parrado, Juan; Tejada, Manuel

    2014-09-01

    We studied the behaviour of oxyfluorfen herbicide at a rate of 4 l ha(-1) on biological properties of a Calcaric Regosol amended with two edaphic biostimulants/biofertilizers (SS, derived from sewage sludge; and CF, derived from chicken feathers). Oxyfluorfen was surface broadcast on 11 March 2013. Two days after application of oxyfluorfen to soil, both biostimulants/biofertilizers (BS) were also applied to the soil. An unamended soil without oxyfluorfen was used as control. For 2, 4, 7, 9, 20, 30, 60, 90 and 120 days of the application of herbicide to the soil and for each treatment, the soil dehydrogenase, urease, β-glucosidase and phosphatase activities were measured. For 2, 7, 30 and 120 days of the application of herbicide to the soil and for each treatment, soil microbial community was determined. The application of both BS to soil without the herbicide increased the enzymatic activities and soil biodiversity, mainly at 7 days of beginning the experiment. However, this stimulation was higher in the soil amended with SS than for CF. The application of herbicide in organic-amended soils decreased the inhibition of soil enzymatic activities and soil biodiversity. Possibly, the low-molecular-weight protein content easily assimilated by soil microorganisms is responsible for less inhibition of these soil biological properties.

  2. Acidic leaching of potentially toxic metals cadmium, cobalt, chromium, copper, nickel, lead, and zinc from two Zn smelting slag materials incubated in an acidic soil.

    PubMed

    Liu, Taoze; Li, Feili; Jin, Zhisheng; Yang, Yuangen

    2018-07-01

    A column leaching study, coupled with acid deposition simulation, was conducted to investigate the leaching of potentially toxic metals (PTM) from zinc smelting slag materials (SSM) after being incubated in an acid Alfisol for 120 days at room temperature. Two SSMs (SSM-A: acidic, 10 yrs exposure with moderate high PTM concentrations versus SSM-B: alkaline, 2 yrs exposure with extremely high PTM concentrations), were used for the incubation at 0.5, 1, 2.5, 5 wt% amendment ratios in triplicate. Five leaching events were conducted at day 1, 3, 7, 14, and 28, and the leaching of PTMs mainly occurred in the first three leaching events, with the highest PTM concentrations in leachate measured from 5 wt% SSM amendments. After leaching, 2.5, 12, 5.5, 14, 11, and 9 wt% of M3 extractable Pb, Zn, Cd, Co, Cr, and Ni could be released from 5 wt% SSM-A amended soils, being respectively 25, 12, 4, 2, 2, and 2 times more than those from 5 wt% SSM-B amended soils. In the leachates, the concentrations of PTMs were mostly affected by leachant pH and were closely correlated to the concentrations of Fe, Al, Ca, Mg and P with Cd, Pb, and Zn showing the most environmental concern. Visual MINTEQ 3.1 modeling suggested metallic ions and sulfate forms as the common chemical species of PTMs in the leachates; whereas, organic bound species showed importance for Cd, Pb, Cu, and Ni, and CdCl + was observed for Cd. Aluminum hydroxy, phosphate, and sulfate minerals prevailed as the saturated minerals, followed by chloropyromorphite (Pb 5 (PO 4 ) 3 Cl) and plumbogummite (PbAl 3 (PO 4 ) 2 (OH) 5 ·H 2 O) in the leachates. This study suggested that incubation of SSMs in acidic soil for a long term can enhance the release of PTMs as the forms of metallic ions and sulfate when subjected to acid deposition leaching. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Pesticide mobility and leachate toxicity in two abandoned mine soils. Effect of organic amendments.

    PubMed

    Rodríguez-Liébana, José Antonio; Mingorance, M Dolores; Peña, Aránzazu

    2014-11-01

    Abandoned mine areas, used in the past for the extraction of minerals, constitute a degraded landscape which needs to be reintegrated to productive or leisure activities. However these soils, mainly composed by silt or sand and with low organic matter content, are vulnerable to organic and inorganic pollutants posing a risk to the surrounding ecosystems and groundwater. Soils from two mining areas from Andalusia were evaluated: one from Nerva (NCL) in the Iberian Pyrite Belt (SW Andalusia) and another one from the iron Alquife mine (ALQ) (SE Andalusia). To improve soil properties and fertility two amendments, stabilised sewage sludge (SSL) and composted sewage sludge (CSL), were selected. The effect of amendment addition on the mobility of two model pesticides, thiacloprid and fenarimol, was assessed using soil columns under non-equilibrium conditions. Fenarimol, more hydrophobic than thiacloprid, only leached from native ALQ, a soil with lower organic carbon (OC) content than NCL (0.21 and 1.4%, respectively). Addition of amendments affected differently pesticide mobility: thiacloprid in the leachates was reduced by 14% in NCL-SSL and by 4% in ALQ-CSL. Soil OC and dissolved OC were the parameters which explained pesticide residues in soil. Chemical analysis revealed that leachates from the different soil columns did not contain toxic element levels, except As in NCL soil. Finally ecotoxicological data showed moderate toxicity in the initial leachates, with an increase coinciding with pesticide maximum concentration. The addition of SSL slightly reduced the toxicity towards Vibrio fischeri, likely due to enhanced retention of pesticides by amended soils. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Evaluation of organic amendment on the effect of cadmium bioavailability in contaminated soils using the DGT technique and traditional methods.

    PubMed

    Yao, Yu; Sun, Qin; Wang, Chao; Wang, Pei-Fang; Ding, Shi-Ming

    2017-03-01

    Organic amendments have been widely proposed as a remediation technology for metal-contaminated soils, but there exist controversial results on their effectiveness. In this study, the effect of pig manure addition on cadmium (Cd) bioavailability in Cd-contaminated soils was systematically evaluated by one dynamic, in situ technique of diffusive gradients in thin films (DGT) and four traditional methods based on the equilibrium theory (soil solution concentration and the three commonly used extractants, i.e., acetic acid (HAc), ethylenediamine tetraacetic acid (EDTA), and calcium chloride (CaCl 2 ). Wheat and maize were selected for measurement of plant Cd uptake. The results showed that pig manure addition could promote the growth of two plants, accompanied by increasing biomasses of shoots and roots with increasing doses of pig manure addition. Correspondingly, increasing additions of pig manure reduced plant Cd uptake and accumulation, as indicated by the decreases of Cd concentrations in shoots and roots. The bioavailable concentrations of Cd in Cd-contaminated soils reflected by the DGT technique obviously decreased with increasing doses of pig manure addition, following the same changing trend as plant Cd uptake. Changes in soil solution Cd concentration and extractable Cd by HAc, EDTA, and CaCl 2 in soils were similar to DGT measurement. Meanwhile, the capability of Cd resupply from solid phase to soil solution decreased with increasing additions of pig manure, as reflected by the decreases in the ratio (R) value of C DGT to C sol . Positive correlations were observed between various bioavailable indicators of Cd in soils and Cd concentrations in the tissues of the two plants. These findings provide stronger evidence that pig manure amendment is effective in reducing Cd mobility and bioavailability in soils and it is an ideal organic material for remediation of Cd-contaminated soils.

  5. Chromium fractionation and plant availability in tannery-sludge amended soil

    NASA Astrophysics Data System (ADS)

    Allué, Josep; Moya Garcés, Alba; Bech, Jaume; Barceló, Juan; Poschenrieder, Charlotte

    2013-04-01

    soils with the highest sludge dose (20 g kg-1). Soils from the different treatments were potted (5 L) and planted with Trigonella foenum graecum seeds (1 plant per pot). Plants were harvested in the vegetative stage and processed for tissue analysis of Cr, Fe, Zn and Pb. A sequential extraction procedure was applied to the soil for getting insight into the operationally defined soil fractions that incorporate the tannery sludge derived Cr. In any of the treatments Cr was detectable in the exchangeable and easily reducible fractions. In control soils around 10% of soil Cr was in the moderately reducible fraction and the rest in the residual fraction. Contrastingly tannery sludge amended soils incorporated most Cr in the moderately reducible fraction extracted by acid oxalate. This distribution in relation to plant Cr concentrations will be discussed. Acknowledgement: Supported by the Spanish Government (project BFU2010-14873)

  6. Effect of biochar or activated carbon amendment on the volatilisation and biodegradation of organic soil pollutants

    NASA Astrophysics Data System (ADS)

    Werner, David; Meynet, Paola; Bushnaf, Khaled

    2013-04-01

    Biochar or activated carbon added to contaminated soil may temporarily reduce the volatilisation of organic pollutants by enhanced sorption. The long-term effect of sorbent amendments on the fate of volatile petroleum hydrocarbon mixtures (VPHs) will depend on the responses of the soil bacterial community members, especially those which may utilize VPHs as carbon substrates. We investigated the volatilisation and biodegradation of VPHs emanating from NAPL sources and migrating through one meter long columns containing unsaturated sandy soil with and without 2% biochar or activated carbon amendment. After 420 days, VPH volatilisation from AC amended soil was less than 10 percent of the cumulative VPH volatilisation flux from unamended soil. The cumulative CO2 volatilisation flux increased more slowly in AC amended soil, but was comparable to the untreated soil after 420 days. This indicated that the pollution attenuation over a 1 meter distance was improved by the AC amendment. Biochar was a weaker VPH sorbent than AC and had a lesser effect on the cumulative VPH and CO2 fluxes. We also investgated the predominant bacterial community responses in sandy soil to biochar and/or VPH addition with a factorially designed batch study, and by analyzing preserved soil samples. Biochar addition alone had only weak effects on soil bacterial communities, while VPH addition was a strong community structure shaping factor. The bacterial community effects of biochar-enhanced VPH sorption were moderated by the limited biomass carrying capacity of the sandy soil investigated which contained only low amounts of inorganic nitrogen. Several Pseudomonas spp., including Pseudomonas putida strains, became dominant in VPH polluted soil with and without biochar. The ability of these versatile VPH degraders to effectively regulate their metabolic pathways according to substrate availabilities may additionally have moderated bacterial community structure responses to the presence of biochar

  7. Impact of wheat straw biochar addition to soil on the sorption, leaching, dissipation of the herbicide (4-chloro-2-methylphenoxy)acetic acid and the growth of sunflower (Helianthus annuus L.).

    PubMed

    Tatarková, Veronika; Hiller, Edgar; Vaculík, Marek

    2013-06-01

    Biochar addition to agricultural soils might increase the sorption of herbicides, and therefore, affect other sorption-related processes such as leaching, dissipation and toxicity for plants. In this study, the impact of wheat straw biochar on the sorption, leaching and dissipation in a soil, and toxicity for sunflower of (4-chloro-2-methylphenoxy)acetic acid (MCPA), a commonly used ionizable herbicide, was investigated. The results showed that MCPA sorption by biochar and biochar-amended soil (1.0wt% biochar) was 82 and 2.53 times higher than that by the non-amended soil, respectively. However, desorption of MCPA from biochar-amended soil was only 1.17 times lower than its desorption in non-amended soil. Biochar addition to soil reduced both MCPA leaching and dissipation. About 35% of the applied MCPA was transported through biochar-amended soil, while up to 56% was recovered in the leachates transported through non-amended soil. The half-life value of MCPA increased from 5.2d in non-amended soil to 21.5 d in biochar-amended soil. Pot experiments with sunflower (Helianthus annuus L.) grown in MCPA-free, but biochar-amended soil showed no positive effect of biochar on the growth of sunflower in comparison to the non-amended soil. However, biochar itself significantly reduced the content of photosynthetic pigments (chlorophyll a, b) in sunflower. There was no significant difference in the phytotoxic effects of MCPA on sunflowers between the biochar-amended soil and the non-amended soil. Furthermore, MCPA had no effect on the photosynthetic pigment contents in sunflower. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. The effect of chemical and organic amendments on sodium exchange equilibria in a calcareous sodic soil.

    PubMed

    Ranjbar, Faranak; Jalali, Mohsen

    2015-11-01

    In this study, the reclamation of a calcareous sodic soil with the exchangeable sodium percentage (ESP) value of 26.6% was investigated using the cheap and readily available chemical and organic materials including natural bentonite and zeolite saturated with calcium (Ca2+), waste calcite, three metal oxide nanoparticles functionalized with an acidic extract of potato residues, and potato residues. Chemical amendments were added to the soil at a rate of 2%, while potato residues were applied at the rates of 2 and 4% by weight. The ESP in the amended soils was reduced in the range of 0.9-4.9% compared to the control soil, and the smallest and the largest decline was respectively observed in treatments containing waste calcite and 4% of potato residues. Despite the reduction in ESP, the values of this parameter were not below 15% at the end of a 40-day incubation period. So, the effect of solutions of varying sodium adsorption ratio (SAR) values of 0, 5, 10, 20, 30, 40, and 50 on sodium (Na+) exchange equilibria was evaluated in batch systems. The empirical models (simple linear, Temkin, and Dubinin-Radushkevich) fitted well to experimental data. The relations of quantity to intensity (Q/I) revealed that the potential buffering capacity for Na+ (PBCNa) varied from 0.275 to 0.337 ((cmolc kg(-1)) (mmol L(-1))(-1/2)) in the control soil and amended soils. The relationship between exchangeable sodium ratio (ESR) and SAR was individually determined for the control soil and amended soils. The values of Gapon selectivity coefficient (KG) of Na+ differed from the value suggested by U.S. Salinity Laboratory (USSL). The PHREEQC, a geochemical computer program, was applied to simulate Na+ exchange isotherms by using the mechanistic cation exchange model (CEM) along with Gaines-Thomas selectivity coefficients. The simulation results indicated that Na+ exchange isotherms and Q/I and ESR-SAR relations were influenced by the type of counter anions. The values of K G increased in

  9. Emission reduction of 1,3-dichloropropene by soil amendment with biochar

    USDA-ARS?s Scientific Manuscript database

    Soil fumigation is important for growing many fruits and vegetable crops, but fumigant emissions may contaminate the atmosphere. Biochar as soil amendments has the potential of mitigating climate change effects. In addition, its high surface area and porosity enable it to adsorb or retain nutrients,...

  10. The mechanisms for 1,3-dichloropropene dissipation in biochar-amended soils

    USDA-ARS?s Scientific Manuscript database

    Biochar has the potential to reduce fumigant emissions to protect air quality; however, the mechanisms are not fully understood. The objective of this study was to determine effects of biochar properties, amendment rate, soil moisture, temperature, and soil type on degradation and adsorption charact...

  11. Soil-plant transfer of Cs-137 and Sr-90 in digestate amended agricultural soils- a lysimeter scale experiment

    NASA Astrophysics Data System (ADS)

    Mehmood, Khalid; Berns, Anne E.; Pütz, Thomas; Burauel, Peter; Vereecken, Harry; Zoriy, Myroslav; Flucht, Reinhold; Opitz, Thorsten; Hofmann, Diana

    2014-05-01

    Radiocesium and radiostrontium are among the most problematic soil contaminants following nuclear fallout due to their long half-lives and high fission yields. Their chemical resemblance to potassium, ammonium and calcium facilitates their plant uptake and thus enhances their chance to reach humans through the food-chain dramatically. The plant uptake of both radionuclides is affected by the type of soil, the amount of organic matter and the concentration of competitive ions. In the present lysimeter scale experiment, soil-plant transfer of Cs-137 and Sr-90 was investigated in an agricultural silty soil amended with digestate, a residue from a biogas plant. The liquid fraction of the digestate, liquor, was used to have higher nutrient competition. Digestate application was done in accordance with the field practice with an application rate of 34 Mg/ha and mixing it in top 5 cm soil, yielding a final concentration of 38 g digestate/Kg soil. The top 5 cm soil of the non-amended reference soil was also submitted to the same mixing procedure to account for the physical disturbance of the top soil layer. Six months after the amendment of the soil, the soil contamination was done with water-soluble chloride salts of both radionuclides, resulting in a contamination density of 66 MBq/m2 for Cs-137 and 18 MBq/m2 for Sr-90 in separate experiments. Our results show that digestate application led to a detectable difference in soil-plant transfer of the investigated radionuclides, effect was more pronounced for Cs-137. A clear difference was observed in plant uptake of different plants. Pest plants displayed higher uptake of both radionuclides compared to wheat. Furthermore, lower activity values were recorded in ears compared to stems for both radionuclides.

  12. Dissolved organic C and N pools in soils amended with composted and thermally-dried sludge as affected by soil tillage systems and sampling depth

    NASA Astrophysics Data System (ADS)

    García-Gil, Juan Carlos; Soler-Rovira, Pedro Angel; García López de Sa, Esther; Polo, Alfredo

    2013-04-01

    Soil tillage practices exert a significant influence on the dynamic of soluble organic C and N pools, affecting nutrient cycling in agricultural systems by enhancing its mineralization through microbial activities or stabilization in soil microaggregates, which contribute to mitigate greenhouse gases emissions. The objective of the present research was to determine the influence of three different soil management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) obtained from wastewater treatment processes on dissolved organic C (water-soluble organic C -WSOC-, carbohydrates, phenolic compounds) and soluble N (total-N, NH4+, NO3-) pools in a long-term field experiment (27 years) conducted on a sandy-loam soil at the experimental station "La Higueruela" (40° 03'N, 4° 24'W) under semi-arid conditions. Both organic amendments were applied at a rate of 30 tonnes per hectare prior to tillage practices. Unamended soils were used as control for each tillage system. Soil sampling was performed two months after tillage practices at the following depths for each treatment: 0-10 cm, 10-20 cm and 20-30 cm. Results obtained for unamended soils showed that no-tillage management increased total-N, NH4+ and NO3- contents at the 0-10 cm depth samples, meanwhile WSC and carbohydrates contents were larger at 20-30 cm depth samples in both moldboard and no-tillage plots. CS and TSS-amended soils presented a general increase in soluble C and N compounds, being significantly higher in TSS-amended soils, as TSS contains a great amount of labile organic C and N substrates due to the lack of stabilization treatment. TSS-amended soils under no-tillage and chisel plowing showed larger N, NH4+ and NO3- content at the 0-10 cm samples, meanwhile moldboard management exhibited larger NH4+ and NO3- content at 10-20 and 20-30 cm samples, possibly due to the incorporation of TSS at deeper depths (20-40 cm). CS

  13. Efficacy of Organic Soil Amendments for Management of Heterodera glycines in Greenhouse Experiments

    PubMed Central

    Grabau, Zane J.; Chen, Senyu

    2014-01-01

    In a repeated greenhouse experiment, organic soil amendments were screened for effects on population density of soybean cyst nematode (SCN), Heterodera glycines, and soybean growth. Ten amendments at various rates were tested: fresh plant material of field pennycress, marigold, spring camelina, and Cuphea; condensed distiller’s solubles (CDS), ash of combusted CDS, ash of combusted turkey manure (TMA), marigold powder, canola meal, and pennycress seed powder. Soybeans were grown for 70 d in field soil with amendments and SCN eggs incorporated at planting. At 40 d after planting (DAP), many amendments reduced SCN egg population density, but some also reduced plant height. Cuphea plant at application rate of 2.9% (amendment:soil, w:w, same below), marigold plant at 2.9%, pennycress seed powder at 0.5%, canola meal at 1%, and CDS at 4.3% were effective against SCN with population reductions of 35.2%, 46.6%, 46.7%, 73.2%, and 73.3% compared with control, respectively. For Experiment 1 at 70 DAP, canola meal at 1% and pennycress seed powder at 0.5% reduced SCN population density 70% and 54%, respectively. CDS at 4.3%, ash of CDS at 0.2%, and TMA at 1% increased dry plant mass whereas CDS at 4.3% and pennycress seed powder at 0.1% reduced plant height. For Experiment 2 at 70 DAP, amendments did not affect SCN population nor plant growth. In summary, some amendments were effective for SCN management, but phytoxicity was a concern. PMID:25276000

  14. Arsenic bioaccessibility in a soil amended with drinking-water treatment residuals in the presence of phosphorus fertilizer.

    PubMed

    Sarkar, D; Quazi, S; Makris, K C; Datta, R; Khairom, A

    2007-10-01

    A laboratory incubation study was conducted to determine the effect of drinking-water treatment residuals (WTRs) on arsenic (As) bioaccessibility and phytoavailability in a poorly As-sorbing soil contaminated with arsenical pesticides and fertilized with triple super phosphate (TSP). The Immokalee soil (a sandy spodosol with minimal As-retention capacity) was amended with 2 WTRs (Al and Fe) at 5 application rates ranging between 0% and 5% wt/wt. Sodium arsenate and TSP were used to spike the soil with 90 mg As kg(-1) and 115 mg P kg(-1), respectively. Bioaccessible As was determined at time 0 (immediately after spiking), and at 6 and 12 months of equilibration using an in vitro gastrointestinal test, and As phytoavailability was measured with a 1-M KC1 extraction test. Arsenic phytoavailability decreased immediately after spiking (20% availability at 5% rate), but only after 6 months for the Al-WTR- and the Fe-WTR-amended soil, respectively. Arsenic bioaccessibility simulated for the stomach and intestine phases showed that the Fe-WTR was more effective than the Al-WTR in resisting the harsh acidic conditions of the human stomach, thus preventing As release. Both the phytoavailable As and the bioaccessible As were significantly correlated (p < 0.001) for soil spiked with either Al- or Fe-WTR. Both WTRs were able to decrease soil As bioaccessibility irrespective of the presence or absence of P, which was added as TSP. Results indicate the potential of WTRs in immobilizing As in contaminated soils fertilized with P, thereby minimizing soil As bioaccessibility and phytoavailability.

  15. Phosphogypsum as a soil fertilizer: Ecotoxicity of amended soil and elutriates to bacteria, invertebrates, algae and plants.

    PubMed

    Hentati, Olfa; Abrantes, Nelson; Caetano, Ana Luísa; Bouguerra, Sirine; Gonçalves, Fernando; Römbke, Jörg; Pereira, Ruth

    2015-08-30

    Phosphogypsum (PG) is a metal and radionuclide rich-waste produced by the phosphate ore industry, which has been used as soil fertilizer in many parts of the world for several decades. The positive effects of PG in ameliorating some soil properties and increasing crop yields are well documented. More recently concerns are emerging related with the increase of metal/radionuclide residues on soils and crops. However, few studies have focused on the impact of PG applications on soil biota, as well as the contribution to soils with elements in mobile fractions of PG which may affect freshwater species as well. In this context the main aim of this study was to assess the ecotoxicity of soils amended with different percentages of Tunisian phosphogypsum (0.0, 4.9, 7.4, 11.1, 16.6 and 25%) and of elutriates obtained from PG - amended soil (0.0, 6.25, 12.5 and 25% of PG) to a battery of terrestrial (Eisenia andrei, Enchytraeus crypticus, Folsomia candida, Hypoaspis aculeifer, Zea mays, Lactuca sativa) and aquatic species (Vibrio fischeri, Daphnia magna, Raphidocelis subcapitata, Lemna minor). Both for amended soils and elutriates, invertebrates (especially D. magna and E. andrei) were the most sensitive species, displaying acute (immobilization) and chronic (reproduction inhibition) effects, respectively. Despite the presence of some concerning metals in PG and elutriates (e.g., zinc and cadmium), the extremely high levels of calcium found in both test mediums, suggest that this element was the mainly responsible for the ecotoxicological effects observed. Terrestrial and aquatic plants were the most tolerant species, which is in line with studies supporting the application of PG to increase crop yields. Nevertheless, no stimulatory effects on growth were observed for any of the species tested despite the high levels of phosphorus added to soils by PG. Given the importance of soil invertebrates for several soil functions and services, this study gives rise to new serious

  16. Sorption kinetics and leachability of heavy metal from the contaminated soil amended with immobilizing agent (humus soil and hydroxyapatite).

    PubMed

    Chaturvedi, Pranav Kumar; Seth, Chandra Shekhar; Misra, Virendra

    2006-08-01

    Release of heavy metals onto the soil as a result of agricultural and industrial activities may pose a serious threat to the environment. This study investigated the kinetics of sorption of heavy metals on the non-humus soil amended with (1:3) humus soil and 1% hydroxyapatite used for in situ immobilization and leachability of heavy metals from these soils. For this, a batch equilibrium experiment was performed to evaluate metal sorption in the presence of 0.05 M KNO(3) background electrolyte solutions. The Langmuir isotherms applied for sorption studies showed that the amount of metal sorbed on the amended soil decreased in the order of Pb(2+)>Zn(2+)>Cd(2+). The data suggested the possibility of immobilization of Pb due to sorption process and immobilization of Zn and Cd by other processes like co-precipitation and ion exchange. The sorption kinetics data showed the pseudo-second-order reaction kinetics rather than pseudo-first-order kinetics. Leachability study was performed at various pHs (ranging from 3 to 10). Leachability rate was slowest for the Pb(2+) followed by Zn(2+) and Cd(2+). Out of the metal adsorbed on the soil only 6.1-21.6% of Pb, 7.3-39% of Zn and 9.3-44.3% of Cd leached out from the amended soil.

  17. Use of commercial soil amendments in initial soils (II) - Impact on soil respiratory and carbon isotopic characteristics

    NASA Astrophysics Data System (ADS)

    Nii-Annang, S.; Rodionov, A.; Dilly, O.; Bens, O.; Raab, T.; Hüttl, R. F.

    2009-04-01

    The search for viable re-cultivation techniques for the reclamation of large scale soil disturbances induced by mining of mineral resources has increasingly received attention in recent times. These techniques should favour plant growth under dry conditions and under nutrient-poor substrates; a problem in the lignite mining district in Lusatia, Germany. Substrates with basal respiration around 0.04 µg CO2 g-1 h-1, which is relatively low compared to mature soils, were amended with two nutrient rich commercial soil additives (CSA 1 and CSA 2). The CSA 1 is a synthetic-mineral mixture and CSA 2 an organo-mineral mixture. The amendment stimulated basal respiration based on both carbon dioxide evolution and oxygen uptake by 150 and 125 % for SCA 1 and CSA 2, respectively when 1 % of each additive was thoroughly mixed with substrate in a laboratory study. The stimulating effect was evident after glucose addition to CSA 2. The CSA 1 application in the field at lower rates still showed apparent stimulation of soil respiratory activities after one year. Similarly, the organo-mineral-mixture has prominent effects on basal respiration and substrate-induced respiration when glucose was added. We concluded that the commercial additives used as long-term amelioration techniques increased both nutrient preservation and, to some extent, soil microbial activity.

  18. Effects of a selenium-laden soil amendment on grapevine metabolism and progression of Pierce’s disease

    USDA-ARS?s Scientific Manuscript database

    Selenium containing soil amendments might be beneficial to growers as selenium may increase resistance to certain plant pathogens and pests. Therefore, grapevines growing in soil with different amounts of selenium-laden amendment were evaluated for metabolism and susceptibility to Pierce’s disease (...

  19. Heavy metal concentrations in earthworms from soil amended with sewage sludge

    USGS Publications Warehouse

    Beyer, W.N.; Chaney, R.L.; Mulhern, B.M.

    1982-01-01

    Metal concentrations in soil may be elevated considerably when metal-laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agricultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P . < 0.05) more Cd (12 times), Cu (2.4 times), Zn (2.0 times), and Pb (1.2 times) than did earthworms from control sites, but the concentrations detected varied greatly and depended on the particular sludge application. Generally, Cd and Zn were concentrated by earthworms relative to soil, and Cu, Pb, and Ni were not concentrated. Concentrations of Cd, Zn, Cu, and Pb in earthworms were correlated (P < 0.05) with those in soil. The ratio of the concentration of metals in earthworms to the concentration of metals in soil tended to be lower in contaminated soil than in clean soil. Concentrations of Cd as high as 100 ppm (dry wt) were detected in earthworms from soil containing only 2 ppm Cd. These concentrations are considered hazardous to wildlife that eat worms. Liming soil decreased Cd concentrations in earthworms slightly (P < 0.05) but had no discernible effect on concentrations of the other metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.

  20. Simultaneous immobilization of metals and arsenic in acidic polluted soils near a copper smelter in central Chile.

    PubMed

    Cárcamo, Valeska; Bustamante, Elena; Trangolao, Elizabeth; de la Fuente, Luz María; Mench, Michel; Neaman, Alexander; Ginocchio, Rosanna

    2012-05-01

    Acidic and metal(oid)-rich topsoils resulted after 34 years of continuous operations of a copper smelter in the Puchuncaví valley, central Chile. Currently, large-scale remediation actions for simultaneous in situ immobilization of metals and As are needed to reduce environmental risks of polluted soils. Aided phytostabilization is a cost-effective alternative, but adequate local available soil amendments have to be identified and management options have to be defined. Efficacy of seashell grit (SG), biosolids (B), natural zeolite (Z), and iron-activated zeolite (AZ), either alone or in mixtures, was evaluated for reducing metal (Cu and Zn) and As solubilization in polluted soils under laboratory conditions. Perennial ryegrass was used to test phytotoxicity of experimental substrates. Soil neutralization to a pH of 6.5 with SG, with or without incorporation of AZ, significantly reduces metal (Cu and Zn) solubilization without affecting As solubilization in soil pore water; furthermore, it eliminates phytotoxicity and excessive metal(oid) accumulation in aerial plant tissues. Addition of B or Z to SG-amended soil does not further reduce metal solubilization into soil pore water, but increase As solubilization due to excessive soil neutralization (pH > 6.5); however, no significant As increase occurs in aerial plant tissues. Simultaneous in situ immobilization of metal(oid) in acidic topsoils is possible through aided phytostabilization.

  1. Effect of Fertilizers and Neem Cake Amendment in Soil on Spore Germination of Arthrobotrys dactyloides

    PubMed Central

    Kumar, D.; Jaiswal, R. K.

    2005-01-01

    Application of fertilizers such as urea, diammonium phosphate (DAP) and muriate of potash in soil adversely affected the spore germination of Arthrobotrys dactyloides. Amendment of soil with urea at the concentrations of 1.0%, 0.5% and 0.1% completely inhibited spore germination and direct trap formation on the conidium, whereas muriate of potash delayed and reduced the spore germination even at the lowest concentration. DAP also inhibited spore germination at 1.0% concentration, while at lower concentration the percentage of spore germination was reduced. Application of neem cake at the concentration of 0.5% also inhibited spore germination after 24 h of amendment. The inhibitory effect of neem cake was reduced after 15 days of amendment, while after 30 days after amendment the inhibitory effect was completely lost and the spore germinated by direct trap as in unamended soil. Nematodes were not attracted to ungerminated spores after 24 h of amendment. After 15 days of amendment nematodes were attracted to agar blocks containing fewer germinated spores after 24 h of incubation but after 48 h of incubation large number of nematodes were attracted and trapped by the germinated spores with direct traps. After 30 days of amendment, larger number of nematodes were attracted and trapped by direct traps. PMID:24049500

  2. Arsenic mobility and bioavailability in paddy soil under iron compound amendments at different growth stages of rice.

    PubMed

    Yu, Huan-Yun; Wang, Xiangqin; Li, Fangbai; Li, Bin; Liu, Chuanping; Wang, Qi; Lei, Jing

    2017-05-01

    Iron (Fe)-based solids can reduce arsenic (As) mobility and bioavailability in soils, which has been well recognized. However, to our knowledge, there are few studies on As uptake at different growth stages of rice under Fe compound amendments. In addition, the formation of Fe plaques at different growth stages of rice has also been rarely reported. Therefore, the present study was undertaken to investigate As mobility and bioavailability in paddy soil under Fe compound amendments throughout the whole growth stage of rice plants. Amendments of poorly crystalline Fe oxides (PC-Fe), FeCl 2 +NaNO 3 and FeCl 2 reduced grain As by 54% ± 3.0%, 52% ± 3.0% and 46% ± 17%, respectively, compared with that of the non-amended control. The filling stage was suggested to be the key stage to take measures to reduce As uptake. At this stage, all soil amendments significantly reduced As accumulation in rice plants. At the maturation stage, PC-Fe amendment significantly reduced mobile pools and increased immobile pools of soil As. Besides, PC-Fe treatment promoted the transformation of Fe fractions from dissolved Fe to adsorbed, poorly crystalline and free Fe oxides. Moreover, significant positive correlations between soil Fe fractions and As fractions were found. Accordingly, we hypothesized that Fe compound amendments might affect the concentration distribution of Fe fractions first and then affect As fractionation in soil and its bioavailability to rice plants indirectly. The formation of Fe plaques varied with growth stages and different treatments. Significantly negative correlations between mobile pools of As and Fe or As in Fe plaques indicated that Fe plaques could immobilize mobile As in soils and thus affect As bioavailability. Overall, the effect of the soil amendments on reduction of As uptake varied with growth stages and different treatments, and further research on the key stage for reducing As uptake is still required. Copyright © 2017 Elsevier Ltd. All

  3. Selected Fe and Mn (nano)oxides as perspective amendments for the stabilization of As in contaminated soils.

    PubMed

    Michálková, Zuzana; Komárek, Michael; Veselská, Veronika; Číhalová, Sylva

    2016-06-01

    An amorphous Mn oxide (AMO), nanomaghemite, and nanomagnetite were used as potential amendments reducing the mobility of As in three contrasting contaminated soils differing in origin of As contamination. Adsorption experiments and XPS analyses combined with incubation batch experiments and pH-static leaching tests were used. The AMO showed excellent adsorption capacity for As(V) reaching a maximum of 1.79 mmol g(-1) at pH 7 and 8. Interestingly, the adsorption capacity in this case decreases with decreasing pH, probably as a result of AMO dissolution at lower pH values. Chemical sorption of As(V) onto AMO was further confirmed with XPS. Both Fe nano-oxides proved the highest adsorption capacity at pH 4 reaching 11 mg g(-1) of adsorbed As(V). The AMO was also the most efficient amendment for decreasing As concentrations in soil solutions during 8 weeks of incubation. Additionally, pH-static leaching tests were performed at pH 4, 5, 6, 7, and natural pH (not adjusted) and AMO again proved the highest ability to decrease As content in leachate. On the other hand, strong dissolution of this amendment at lower pH values (especially pH 4) was observed. For that reason, AMO appears as a promising stabilizing agent for As, especially in neutral, alkaline, or slightly acidic soils, where As(V) species are expected to be more mobile.

  4. Effect of different organic amendments on the dissipation of linuron, diazinon and myclobutanil in an agricultural soil incubated for different time periods.

    PubMed

    Marín-Benito, Jesús M; Herrero-Hernández, Eliseo; Andrades, M Soledad; Sánchez-Martín, María J; Rodríguez-Cruz, M Sonia

    2014-04-01

    Dissipation kinetics of pesticides belonging to three chemical groups (linuron, diazinon and myclobutanil) was studied in an unamended agricultural soil and in this soil amended with three organic residues: sewage sludge (SS), grape marc (GM) and spent mushroom substrate (SMS). The soils were incubated with the residues outdoors for one and 12 months. Mineralized, extracted and non-extractable fractions were also studied for (14)C-linuron and (14)C-diazinon. The dissipation kinetics was fitted to single first-order or first-order multicompartment models. The dissipation rate (k) decreased in the order diazinon>linuron>myclobutanil, and DT50 values decreased for linuron (1.6-4.8 times) or increased for myclobutanil (1.7-2.6 times) and diazinon (1.8-2.3 times) in the amended soils relative to the unamended soil. The lowest DT50 values for the three pesticides were recorded in GM-amended soil, and the highest values in SMS-amended soil. After 12 months of soil incubation, DT50 values decreased in both the unamended and amended soils for linuron, but increased for the unamended and SMS-amended soil for diazinon and myclobutanil. A certain relationship was observed between the sorption of pesticides by the soils and DT50 values, although it was significant only for myclobutanil (p<0.05). Dissipation mechanism recorded the lowest mineralization of (14)C-pesticides in the GM-soil despite the highest dissipation rate in this soil. The extracted (14)C-residues decreased with incubation time, with increased formation of non-extractable residues, higher in amended soils relative to the unamended soil. Soil dehydrogenase activity was, in general, stimulated by the addition of the organic amendments and pesticides to the soil after one month and 12 months of incubation. The results obtained revealed that the simultaneous use of amendments and pesticides in soils requires a previous study in order to check the environmental specific persistence of these compounds and their

  5. Oligotyping reveals stronger relationship of organic soil bacterial community structure with N-amendments and soil chemistry in comparison to that of mineral soil at Harvard Forest, MA, USA

    Treesearch

    Swathi A. Turlapati; Rakesh Minocha; Stephanie Long; Jordan Ramsdell; Subhash C. Minocha

    2015-01-01

    The impact of chronic nitrogen amendments on bacterial communities was evaluated at Harvard Forest, Petersham, MA, USA. Thirty soil samples (3 treatments × 2 soil horizons × 5 subplots) were collected in 2009 from untreated (control), low nitrogen-amended (LN; 50 kg NH4NO3ha-1yr

  6. Use of Fe/Al drinking water treatment residuals as amendments for enhancing the retention capacity of glyphosate in agricultural soils.

    PubMed

    Zhao, Yuanyuan; Wendling, Laura A; Wang, Changhui; Pei, Yuansheng

    2015-08-01

    Fe/Al drinking water treatment residuals (WTRs), ubiquitous and non-hazardous by-products of drinking water purification, are cost-effective adsorbents for glyphosate. Given that repeated glyphosate applications could significantly decrease glyphosate retention by soils and that the adsorbed glyphosate is potentially mobile, high sorption capacity and stability of glyphosate in agricultural soils are needed to prevent pollution of water by glyphosate. Therefore, we investigated the feasibility of reusing Fe/Al WTR as a soil amendment to enhance the retention capacity of glyphosate in two agricultural soils. The results of batch experiments showed that the Fe/Al WTR amendment significantly enhanced the glyphosate sorption capacity of both soils (p<0.001). Up to 30% of the previously adsorbed glyphosate desorbed from the non-amended soils, and the Fe/Al WTR amendment effectively decreased the proportion of glyphosate desorbed. Fractionation analyses further demonstrated that glyphosate adsorbed to non-amended soils was primarily retained in the readily labile fraction (NaHCO3-glyphosate). The WTR amendment significantly increased the relative proportion of the moderately labile fraction (HCl-glyphosate) and concomitantly reduced that of the NaHCO3-glyphosate, hence reducing the potential for the release of soil-adsorbed glyphosate into the aqueous phase. Furthermore, Fe/Al WTR amendment minimized the inhibitory effect of increasing solution pH on glyphosate sorption by soils and mitigated the effects of increasing solution ionic strength. The present results indicate that Fe/Al WTR is suitable for use as a soil amendment to prevent glyphosate pollution of aquatic ecosystems by enhancing the glyphosate retention capacity in soils. Copyright © 2015. Published by Elsevier B.V.

  7. Nitrous oxide production from soils amended with biogas residues and cattle slurry.

    PubMed

    Abubaker, J; Odlare, M; Pell, M

    2013-07-01

    The amount of residues generated from biogas production has increased dramatically due to the worldwide interest in renewable energy. A common way to handle the residues is to use them as fertilizers in crop production. Application of biogas residues to agricultural soils may be accompanied with environmental risks, such as increased NO emission. In 24-d laboratory experiments, NO dynamics and total production were studied in arable soils (sandy, clay, and organic) amended with one of two types of anaerobically digested biogas residues (BR-A and BR-B) generated from urban and agricultural waste and nondigested cattle slurry (CS) applied at rates corresponding to 70 kg NH-N ha. Total NO-N losses from the sandy soil were higher after amendment with BR-B (0.32 g NO-N m) than BR-A or CS (0.02 and 0.18 g NO-N m, respectively). In the clay soil, NO-N losses were very low for CS (0.02 g NO-N m) but higher for BR-A and BR-B (0.25 and 0.15 g NO-N m, respectively). In the organic soil, CS gave higher total NO-N losses (0.31 g NO-N m) than BR-A or BR-B (0.09 and 0.08 g NO-N m, respectively). Emission peaks differed considerably between soils, occurring on Day 1 in the organic soil and on Days 11 to 15 in the sand, whereas in the clay the peak varied markedly (Days 1, 6, and 13) depending on residue type. In all treatments, NH concentration decreased with time, and NO concentration increased. Potential ammonium oxidation and potential denitrification activity increased significantly in the amended sandy soil but not in the organic soil and only in the clay amended with CS. The results showed that fertilization with BR can increase NO emissions and that the size is dependent on the total N and organic C content of the slurry and on soil type. In conclusion, the two types of BR and the CS are not interchangeable regarding their effects on NO production in different soils, and, hence, matching fertilizer type to soil type could reduce NO emissions. For instance, it could be

  8. Effect of biosludge and biofertilizer amendment on growth of Jatropha curcas in heavy metal contaminated soils.

    PubMed

    Juwarkar, Asha Ashok; Yadav, Santosh Kumar; Kumar, Phani; Singh, Sanjeev Kumar

    2008-10-01

    The pot experiments were conducted to evaluate the effect of different concentrations of arsenic, chromium and zinc contaminated soils, amended with biosludge and biofertilizer on the growth of Jatropha curcas which is a biodiesel crop. The results further showed that biosludge alone and in combination with biofertilizer significantly improved the survival rates and enhanced the growth of the plant. With the amendments, the plant was able to grow and survive upto 500, 250 and 4,000 mg kg(-1) of As, Cr and Zn contaminated soils, respectively. The results also showed that zinc enhanced the growth of J. curcas more as compared to other metals contaminated soils. The heavy metal accumulation in plant increased with increasing concentrations of heavy metals in soil, where as a significant reduction in the metal uptake in plant was observed, when amended with biosludge and biofertilizer and biosludge alone. It seems that the organic matter present in the biosludge acted as metal chelator thereby reducing the toxicity of metals to the plant. Findings suggest that plantation of J. curcas may be promoted in metal contaminated soils, degraded soils or wasteland suitably after amending with organic waste.

  9. Enhanced phytoextraction: II. Effect of EDTA and citric acid on heavy metal uptake by Helianthus annuus from a calcareous soil.

    PubMed

    Lesage, E; Meers, E; Vervaeke, P; Lamsal, S; Hopgood, M; Tack, F M G; Verloo, M G

    2005-01-01

    High biomass producing plant species, such as Helianthus annuus, have potential for removing large amounts of trace metals by harvesting the aboveground biomass if sufficient metal concentrations in their biomass can be achieved However, the low bioavailability of heavy metals in soils and the limited translocation of heavy metals to the shoots by most high biomass producing plant species limit the efficiency of the phytoextraction process. Amendment of a contaminated soil with ethylene diamine tetraacetic acid (EDTA) or citric acid increases soluble heavy metal concentrations, potentially rendering them more available for plant uptake. This article discusses the effects of EDTA and citric acid on the uptake of heavy metals and translocation to aboveground harvestable plant parts in Helianthus annuus. EDTA was included in the research for comparison purposes in our quest for less persistent alternatives, suitable for enhanced phytoextraction. Plants were grown in a calcareous soil moderately contaminated with Cu, Pb, Zn, and Cd and treated with increasing concentrations of EDTA (0.1, 1, 3, 5, 7, and 10 mmol kg(-1) soil) or citric acid (0.01, 0.05, 0.25, 0.442, and 0.5 mol kg(-1) soil). Heavy metal concentrations in harvested shoots increased with EDTA concentration but the actual amount of phytoextracted heavy metals decreased at high EDTA concentrations, due to severe growth depression. Helianthus annuus suffered heavy metal stress due to the significantly increased bioavailable metal fraction in the soil. The rapid mineralization of citric acid and the high buffering capacity of the soil made citric acid inefficient in increasing the phytoextracted amounts of heavy metals. Treatments that did not exceed the buffering capacity of the soil (< 0.442 mol kg(-1) soil) did not result in any significant increase in shoot heavy metal concentrations. Treatments with high concentrations resulted in a dissolution of the carbonates and compaction of the soil. These

  10. Shifts in soil chemical properties and bacterial communities responding to biotransformed dry olive residue used as organic amendment.

    PubMed

    Siles, José A; Cajthaml, Tomas; Hernández, Paola; Pérez-Mendoza, Daniel; García-Romera, Inmaculada; Sampedro, Inmaculada

    2015-07-01

    Dry olive residue (DOR) is a waste product derived from olive oil extraction and has been proposed as an organic amendment. However, it has been demonstrated that a pre-treatment, such as its transformation by saprophytic fungi, is required before DOR soil application. A greenhouse experiment was designed where 0 and 50 g kg(-1) of raw DOR (DOR), Coriolopsis floccosa-transformed DOR (CORDOR) and Fusarium oxysporum-transformed DOR (FUSDOR) were added to soil. Analyses of the soil chemical properties as well as the structure and relative abundance of bacterial and actinobacterial communities were conducted after 0, 30 and 60 days following amendment. The different amendments produced a slight decrease in soil pH and significant increases in carbon fractions, C/N ratios, phenols and K, with these increases being more significant after DOR application. Quantitative PCR assays of the 16S rRNA gene and PLFA analyses showed that all amendments favoured bacterial growth at 30 and 60 days, although actinobacterial proliferation was more evident after CORDOR and FUSDOR application at 60 days. Bacterial and actinobacterial DGGE multivariate analyses showed that the amendments produced structural changes in both communities, especially after 60 days of amendment. PLFA data analysis identified changes in soil microbial communities according to the amendment considered, with FUSDOR and CORDOR being less disruptive than DOR. Finally, integrated analysis of all data monitored in the present study enabled us to conclude that the greatest impact on soil properties was caused by DOR at 30 days and that soil showed some degree of resilience after this time.

  11. SITE EVALUATION OF SOIL AMENDMENT TECHNOLOGIES AT THE CROOKSVILLE/ROSEVILLE POTTERY AREA OF CONCERN - STAR ORGANICS SOIL RESCUE CAPSULE

    EPA Science Inventory

    This report briefly summarizes Star Organics treatment technology demonstration of a soil amendment process for lead contaminated soil at Roseville, OH. The evaluation included leaching, bioavailability, geotechnical, and geochemical testing methods.

  12. Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers.

    PubMed

    Christel, Wibke; Zhu, Kun; Hoefer, Christoph; Kreuzeder, Andreas; Santner, Jakob; Bruun, Sander; Magid, Jakob; Jensen, Lars Stoumann

    2016-06-01

    Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residue sphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O2 content and had emitted significantly more CO2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to

  13. Selenium biofortification of broccoli and carrots grown in soil amended with Se-enriched hyperaccumulator Stanleya pinnata.

    PubMed

    Bañuelos, Gary S; Arroyo, Irvin; Pickering, Ingrid J; Yang, Soo In; Freeman, John L

    2015-01-01

    Amending soils with Se-hyperaccumulator plant derived sources of selenium (Se) may be useful for increasing the Se content in food crops in Se-deficient regions of the world. In this study we evaluated total Se and the different chemical species of Se in broccoli and carrots grown in soils amended with ground shoots of the Se-hyperaccumulator Stanleyapinnata. With increasing application rates of S. pinnata, total plant Se concentrations increased to nutritionally ideal levels inside edible parts. Selenium compounds in aqueous extracts were analyzed by SAX-HPLC-ICPMS and identified as a variety of mainly organic-Se forms. Together with bulk Se K-edge X-ray absorption near-edge structure (XANES) analysis performed on broccoli florets, carrot roots and shoots, dried ground S. pinnata, and the amended soil at post-plant, we demonstrate that Se-enriched S. pinnata is valuable as a soil amendment for enriching broccoli and carrots with healthful forms of organic-Se. Published by Elsevier Ltd.

  14. Trace element biogeochemistry in the soil-water-plant system of a temperate agricultural soil amended with different biochars.

    PubMed

    Kloss, Stefanie; Zehetner, Franz; Buecker, Jannis; Oburger, Eva; Wenzel, Walter W; Enders, Akio; Lehmann, Johannes; Soja, Gerhard

    2015-03-01

    Various biochar (BC) types have been investigated as soil amendment; however, information on their effects on trace element (TE) biogeochemistry in the soil-water-plant system is still scarce. In the present study, we determined aqua-regia (AR) and water-extractable TEs of four BC types (woodchips (WC), wheat straw (WS), vineyard pruning (VP), pyrolyzed at 525 °C, of which VP was also pyrolyzed at 400 °C) and studied their effects on TE concentrations in leachates and mustard (Sinapis alba L.) tissue in a greenhouse pot experiment. We used an acidic, sandy agricultural soil and a BC application rate of 3% (w/w). Our results show that contents and extractability of TEs in the BCs and effectuated changes of TE biogeochemistry in the soil-water-plant system strongly varied among the different BC types. High AR-digestable Cu was found in VP and high B contents in WC. WS had the highest impact on TEs in leachates showing increased concentrations of As, Cd, Mo, and Se, whereas WC application resulted in enhanced leaching of B. All BC types increased Mo and decreased Cu concentrations in the plant tissue; however, they showed diverging effects on Cu in the leachates with decreased concentrations for WC and WS, but increased concentrations for both VPs. Our results demonstrate that BCs may release TEs into the soil-water-plant system. A BC-induced liming effect in acidic soils may lead to decreased plant uptake of cationic TEs, including Pb and Cd, but may enhance the mobility of anionic TEs like Mo and As. We also found that BCs with high salt contents (e.g., straw-based BCs) may lead to increased mobility of both anionic and cationic TEs in the short term.

  15. Importance of organic amendment characteristics on bioremediation of PAH-contaminated soil.

    PubMed

    Lukić, B; Huguenot, D; Panico, A; Fabbricino, M; van Hullebusch, E D; Esposito, G

    2016-08-01

    This study investigates the importance of the organic matter characteristics of several organic amendments (i.e., buffalo manure, food and kitchen waste, fruit and vegetables waste, and activated sewage sludge) and their influence in the bioremediation of a polycyclic aromatic hydrocarbons (PAH)-contaminated soil. The removal of low molecular weights (LMW) and high molecular weights (HMW) PAHs was monitored in four bioremediation reactors and used as an indicator of the role of organic amendments in contaminant removal. The total initial concentration of LMW PAHs was 234 mg kg(-1) soil (dry weight), while the amount for HMW PAHs was 422 mg kg(-1) soil (dry weight). Monitoring of operational parameters and chemical analysis was performed during 20 weeks. The concentrations of LMW PAH residues in soil were significantly lower in reactors that displayed a mesophilic phase, i.e., 11 and 15 %, compared to reactors that displayed a thermophilic phase, i.e., 29 and 31 %. Residual HMW PAHs were up to five times higher compared to residual LMW PAHs, depending on the reactor. This demonstrated that the amount of added organic matter and macronutrients such as nitrogen and phosphorus, the biochemical organic compound classes (mostly soluble fraction and proteins), and the operational temperature are important factors affecting the overall efficiency of bioremediation. On that basis, this study shows that characterization of biochemical families could contribute to a better understanding of the effects of organic amendments and clarify their different efficiency during a bioremediation process of PAH-contaminated soil.

  16. EVALUATION OF EXTRACTION AND SPECTROSCOPIC METHODS FOR PB SPECIATION IN AN AMENDED SOIL

    EPA Science Inventory

    Immobilization of pyromorphite (Pbs(PO4hCI) via P amendments to Pb contaminated soils is proving to be a viable method of remediation. However, the issue of ascertaining the amount of soil Pb converted to pyromorphite is difficult in heterogeneous soil systems. Previous attempts ...

  17. Dynamics of organic matter and microbial populations in amended soil: a multidisciplinary approach

    NASA Astrophysics Data System (ADS)

    Gigliotti, Giovanni; Pezzolla, Daniela; Zadra, Claudia; Albertini, Emidio; Marconi, Gianpiero; Turchetti, Benedetta; Buzzini, Pietro

    2013-04-01

    The application of organic amendments to soils, such as pig slurry, sewage sludge and compost is considered a tool for improving soil fertility and enhancing C stock. The addition of these different organic materials allows a good supply of nutrients for plants but also contributes to C sequestration, affects the microbial activity and the transformation of soil organic matter (SOM). Moreover, the addition of organic amendment has gained importance as a source of greenhouse gas (GHG) emissions and then as a cause of the "Global Warming". Therefore, it is important to investigate the factors controlling the SOM mineralization in order to improve soil C sequestration and decreasing at the same time the GHG emissions. The quality of organic matter added to the soil will play an important role in these dynamics, affecting the microbial activity and the changes in microbial community structure. A laboratory, multidisciplinary experiment was carried out to test the effect of the amendment by anaerobic digested livestock-derived organic materials on labile organic matter evolution and on dynamics of microbial population, this latter both in terms of consistence of microbial biomass, as well as in terms of microbial biodiversity. Different approaches were used to study the microbial community structure: chemical (CO2 fluxes, WEOC, C-biomass, PLFA), microbiological (microbial enumeration) and molecular (DNA extraction and Roche 454, Next Generation Sequencing, NGS). The application of fresh digestate, derived from the anaerobic treatment of animal wastes, affected the short-term dynamics of microbial community, as reflected by the increase of CO2 emissions immediately after the amendment compared to the control soil. This is probably due to the addition of easily available C added with the digestate, demonstrating that this organic material was only partially stabilized by the anaerobic process. In fact, the digestate contained a high amounts of available C, which led to

  18. Simultaneous production of l-lactic acid with high optical activity and a soil amendment with food waste that demonstrates plant growth promoting activity.

    PubMed

    Kitpreechavanich, Vichien; Hayami, Arisa; Talek, Anfal; Chin, Clament Fui Seung; Tashiro, Yukihiro; Sakai, Kenji

    2016-07-01

    A unique method to produce highly optically-active l-lactic acid and soil amendments that promote plant growth from food waste was proposed. Three Bacillus strains Bacillus subtilis KBKU21, B. subtilis N3-9 and Bacillus coagulans T27, were used. Strain KBKU21 accumulated 36.9 g/L l-lactic acid with 95.7% optical activity and 98.2% l-lactic acid selectivity when fermented at 43°C for 84 h in a model kitchen refuse (MKR) medium. Residual precipitate fraction (anaerobically-fermented MKR (AFM) compost) analysis revealed 4.60%, 0.70% and 0.75% of nitrogen (as N), phosphorous (as P2O5), and potassium (as K2O), respectively. Additionally, the carbon to nitrogen ratio decreased from 13.3 to 10.6. AFM compost with KBKU21 promoted plant growth parameters, including leaf length, plant height and fresh weight of Brassica rapa (Komatsuna), than that by chemical fertilizers or commercial compost. The concept provides an incentive for the complete recycling of food waste, contributing towards a sustainable production system. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  19. Marble waste and pig manure amendments decrease metal availability, increase soil quality and facilitate vegetation development in bare mine soils

    NASA Astrophysics Data System (ADS)

    Zornoza, Raúl; Faz, Ángel; Martínez-Martínez, Silvia; Acosta, José A.; Gómez, M. Dolores; Ángeles Muñoz, M.

    2013-04-01

    In order to bring out a functional and sustainable land use in a highly contaminated mine tailing, firstly environmental risks have to be reduced or eliminated by suitable reclamation activities. Tailing ponds pose environmental hazards, such as acidity and toxic metals reaching to waters through wind and water erosions and leaching. As a consequence, soils have no vegetation and low soil organic matter and nutrients. Various physicochemical and biochemical properties, together with exchangeable metals were measured before, 6 months and 12 months after the application of marble waste and pigs manure as reclamation strategy in a tailing pond from SE Spain to reduce hazards for environment and human health. Three months after the last addition of amendments, eight different native shrub species where planted for phytostabilization. Results showed the pH increased up to neutrality. Aggregates stability, organic carbon, total nitrogen, cation exchange capacity, bioavailable phosphorus and potassium, microbial biomass and microbial activity increased with the application of the amendments, while exchangeable metals drastically decreased (~90%). After one year of plantation, only 20% planted species died, with a high growth of survivals reaching flowering and fructification. This study confirms the high effectiveness of initial applications of marble wastes together with pig manure and plantation of shrub species to initialize the recovery of the ecosystem in bare mine soils under Mediterranean semiarid conditions. Key Words: pig manure, marble waste, heavy metals, mine soil. Acknowledgements This work has been funded by the European Union LIFE+ project MIPOLARE (LIFE09 ENV/ES/000439). J.A. Acosta acknowledges a "Saavedra Fajardo" contract from Comunidad Autónoma de Murcia (Spain)

  20. Time evolution of the general characteristics and Cu retention capacity in an acid soil amended with a bentonite winery waste.

    PubMed

    Fernández-Calviño, David; Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel

    2015-03-01

    The effect of bentonite waste added to a "poor" soil on its general characteristic and copper adsorption capacity was assessed. The soil was amended with different bentonite waste concentrations (0, 10, 20, 40 and 80 Mg ha(-1)) in laboratory pots, and different times of incubation of samples were tested (one day and one, four and eight months). The addition of bentonite waste increased the pH, organic matter content and phosphorus and potassium concentrations in the soil, being stable for P and K, whereas the organic matter decreased with time. Additionally, the copper sorption capacity of the soil and the energy of the Cu bonds increased with bentonite waste additions. However, the use of this type of waste in soil presented important drawbacks for waste dosages higher than 20 Mg ha(-1), such as an excessive increase of the soil pH and an increase of copper in the soil solution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Field versus laboratory experiments to evaluate the fate of azoxystrobin in an amended vineyard soil.

    PubMed

    Herrero-Hernández, E; Marín-Benito, J M; Andrades, M S; Sánchez-Martín, M J; Rodríguez-Cruz, M S

    2015-11-01

    This study reports the effect that adding spent mushroom substrate (SMS) to a representative vineyard soil from La Rioja region (Spain) has on the behaviour of azoxystrobin in two different environmental scenarios. Field dissipation experiments were conducted on experimental plots amended at rates of 50 and 150 t ha(-1), and similar dissipation experiments were simultaneously conducted in the laboratory to identify differences under controlled conditions. Azoxystrobin dissipation followed biphasic kinetics in both scenarios, although the initial dissipation phase was much faster in the field than in the laboratory experiments, and the half-life (DT50) values obtained in the two experiments were 0.34-46.3 days and 89.2-148 days, respectively. Fungicide residues in the soil profile increased in the SMS amended soil and they were much higher in the top two layers (0-20 cm) than in deeper layers. The persistence of fungicide in the soil profile is consistent with changes in azoxystrobin adsorption by unamended and amended soils over time. Changes in the dehydrogenase activity (DHA) of soils under different treatments assayed in the field and in the laboratory indicated that SMS and the fungicide had a stimulatory effect on soil DHA. The results reveal that the laboratory studies usually reported in the literature to explain the fate of pesticides in amended soils are insufficient to explain azoxystrobin behaviour under real conditions. Field studies are necessary to set up efficient applications of SMS and fungicide, with a view to preventing the possible risk of water contamination. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Bioaccessibility of polycyclic aromatic hydrocarbons in activated carbon or biochar amended vegetated (Salix viminalis) soil.

    PubMed

    Oleszczuk, Patryk; Godlewska, Paulina; Reible, Danny D; Kraska, Piotr

    2017-08-01

    The aim of the present study was to determine the effect of activated carbon (AC) or biochars on the bioaccessibility (C bioacc ) of polycyclic aromatic hydrocarbons (PAHs) in soils vegetated with willow (Salix viminalis). The study determined the effect of willow on the C bioacc PAHs and the effect of the investigated amendments on changes in dissolved organic carbon (DOC), crop yield and the content of PAHs in plants. PAH-contaminated soil was amended with 2.5 wt% AC or biochar. Samples from individual plots with and without plants were collected at the beginning of the experiment and after 3, 6, 12 and 18 months. The C bioacc PAHs were determined using sorptive bioaccessibility extraction (SBE) (silicon rods and hydroxypropyl-β-cyclodextrin). Both AC and biochar caused a decrease in the C bioacc PAHs. Immediately after adding AC, straw-derived biochar or willow-derived biochar to the soil, the reduction in the sum of 16 (Σ16) C bioacc PAHs was 70.3, 38.0, and 29.3%, respectively. The highest reduction of C bioacc was observed for 5- and 6-ring PAHs (from 54.4 to 100%), whereas 2-ring PAHs were reduced only 8.0-25.4%. The reduction of C bioacc PAHs increased over time. Plants reduced C bioacc in all soils although effects varied by soil treatment and PAH. Willow grown in AC- and biochar-amended soil accumulated less phenanthrene than in the control soil. The presence of AC in the soil also affected willow yield and shoot length and DOC was reduced from 53.5 to 66.9% relative to unamended soils. In the biochars-amended soil, no changes in soil DOC content were noted nor effects on willow shoot length. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Soil ionomic and enzymatic responses and correlations to fertilizations amended with and without organic fertilizer in long-term experiments.

    PubMed

    Feng, Xumeng; Ling, Ning; Chen, Huan; Zhu, Chen; Duan, Yinghua; Peng, Chang; Yu, Guanghui; Ran, Wei; Shen, Qirong; Guo, Shiwei

    2016-04-15

    To investigate potential interactions between the soil ionome and enzyme activities affected by fertilization with or without organic fertilizer, soil samples were collected from four long-term experiments over China. Irrespective of variable interactions, fertilization type was the major factor impacting soil ionomic behavior and accounted for 15.14% of the overall impact. Sampling site was the major factor affecting soil enzymatic profile and accounted for 34.25% of the overall impact. The availabilities of Pb, La, Ni, Co, Fe and Al were significantly higher in soil with only chemical fertilizer than the soil with organic amendment. Most of the soil enzyme activities, including α-glucosidase activity, were significantly activated by organic amendment. Network analysis between the soil ionome and the soil enzyme activities was more complex in the organic-amended soils than in the chemical fertilized soils, whereas the network analysis among the soil ions was less complex with organic amendment. Moreover, α-glucosidase was revealed to generally harbor more corrections with the soil ionic availabilities in network. We concluded that some of the soil enzymes activated by organic input can make the soil more vigorous and stable and that the α-glucosidase revealed by this analysis might help stabilize the soil ion availability.

  4. Soil ionomic and enzymatic responses and correlations to fertilizations amended with and without organic fertilizer in long-term experiments

    PubMed Central

    Feng, Xumeng; Ling, Ning; Chen, Huan; Zhu, Chen; Duan, Yinghua; Peng, Chang; Yu, Guanghui; Ran, Wei; Shen, Qirong; Guo, Shiwei

    2016-01-01

    To investigate potential interactions between the soil ionome and enzyme activities affected by fertilization with or without organic fertilizer, soil samples were collected from four long-term experiments over China. Irrespective of variable interactions, fertilization type was the major factor impacting soil ionomic behavior and accounted for 15.14% of the overall impact. Sampling site was the major factor affecting soil enzymatic profile and accounted for 34.25% of the overall impact. The availabilities of Pb, La, Ni, Co, Fe and Al were significantly higher in soil with only chemical fertilizer than the soil with organic amendment. Most of the soil enzyme activities, including α-glucosidase activity, were significantly activated by organic amendment. Network analysis between the soil ionome and the soil enzyme activities was more complex in the organic-amended soils than in the chemical fertilized soils, whereas the network analysis among the soil ions was less complex with organic amendment. Moreover, α-glucosidase was revealed to generally harbor more corrections with the soil ionic availabilities in network. We concluded that some of the soil enzymes activated by organic input can make the soil more vigorous and stable and that the α-glucosidase revealed by this analysis might help stabilize the soil ion availability. PMID:27079657

  5. Effects of arbuscular mycorrhizal inoculation and biochar amendment on maize growth, cadmium uptake and soil cadmium speciation in Cd-contaminated soil.

    PubMed

    Liu, Ling; Li, Jiwei; Yue, Feixue; Yan, Xinwei; Wang, Fayuan; Bloszies, Sean; Wang, Yanfang

    2018-03-01

    Experiments conducted to understand how arbuscular mycorrhizal (AM) inoculation or biochar application affect plant growth and heavy metal uptake have thus far looked at single applications of either soil amendment. There is little evidence of their synergistic effects, in particular for plants grown in cadmium (Cd) contaminated soil. We conducted a mesocosm experiment to investigate the effect of AM inoculation (Glomus intraradices BEG 141) and/or wheat-straw biochar amendment on maize (Zea mays L. cv. Hongdan No. 897) growth, antioxidant enzymatic activities, and Cd uptake, as well as soil Cd speciation under applications of 0, 3, 6 mg Cd per kg soil. Applying either AM inoculant or biochar alone significantly increased maize growth and reduced Cd uptake. Furthermore, solo AM inoculation alleviating Cd stress more fully than biochar, in turn facilitating maize growth and decreasing soil Cd translocation into plant tissue. Still, solo biochar amendment was more effective at inducing soil alkalinization and contributing to Cd immobilization. Adding biochar together with AM inoculant significantly promoted fungal populations compared to a control. Amending soil with AM inoculant and biochar together produced the largest increase in maize growth and decrease in tissue Cd concentrations. This effect was additive, with 79.1% greater biomass, 51.42%, 82.91%, 43.96% higher activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and 50.06%, 67.19%, 58.04% and 76.19% lower Cd concentrations in roots, stems, leaves, and ears, respectively, at a 6 mg kg -1 Cd contamination rate. The combined treatment also had a synergistic effect on inducing soil alkalinization and causing Cd immobilization, and decreasing Cd phytoavailability and post-harvest transfer risks. These results suggest that AM inoculation in combination with biochar application may be applicable not only for maize production but also for phytostabilization of Cd-contaminated soil

  6. Significance of various soil amendments to borrow pit reclamation with loblolly pine and fescue

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berry, C.R.; Marx, D.H.

    Loblolly pine seedlings with ectomycorrhizae formed by Pisolithus tinctorius (Pt) or naturally occurring Thelephora terrestris (Tt) were planted on a borrow pit in South Carolina in plots with no amendment; with fertilizer plus dolomitic limestone alone and with pine bark or bottom ash or bark and ash together; or with dried sewage sludge alone and with bark or ash or bark and ash together. All plots were subsoiled, disked, and seeded to fescue grass before planting pine seedlings. Naturally occurring Pt formed abundant ectomycorrhizae on all Tt seedlings by the end of the first season, precluding any specific ectomycorrhizal fungusmore » effect for the duration of the study. Sewage sludge alone or with bark or ash amendments dramatically improved pine seedling growth and grass biomass in comparison with other soil treatments. Mean seedling volume (D/sup 2/H) was 28 times greater and grass biomass was five times greater in the sludge plots than on nonsludge plots. Generally, soil amended with sludge contained more N, P, organic matter, and had a higher cation exchange capacity than soil of other treatments. Foliage of pine seedlings in sludge-amended soil also contained more N and less Ca than other seedlings. The significance of these results to reclamation of borrow pits is discussed.« less

  7. Biosolid colloid-mediated transport of copper, zinc, and lead in waste-amended soils.

    PubMed

    Karathanasis, A D; Johnson, D M C; Matocha, C J

    2005-01-01

    Increasing land applications of biosolid wastes as soil amendments have raised concerns about potential toxic effects of associated metals on the environment. This study investigated the ability of biosolid colloids to transport metals associated with organic waste amendments through subsurface soil environments with leaching experiments involving undisturbed soil monoliths. Biosolid colloids were fractionated from a lime-stabilized, an aerobically digested, and a poultry manure organic waste and applied onto the monoliths at a rate of 0.7 cm/h. Eluents were monitored for Cu, Zn, Pb, and colloid concentrations over 16 to 24 pore volumes of leaching. Mass-balance calculations indicated significantly higher (up to 77 times) metal elutions in association with the biosolid colloids in both total and soluble fractions over the control treatments. Eluted metal loads varied with metal, colloid, and soil type, following the sequences Zn = Cu > Pb, and ADB > PMB > LSB colloids. Colloid and metal elution was enhanced by decreasing pH and colloid size, and increasing soil macroporosity and organic matter content. Breakthrough curves were mostly irregular, showing several maxima and minima as a result of preferential macropore flow and multiple clogging and flushing cycles. Soil- and colloid-metal sorption affinities were not reliable predictors of metal attenuation/elution loads, underscoring the dynamic nature of transport processes. The findings demonstrate the important role of biosolid colloids as contaminant carriers and the significant risk they pose, if unaccounted, for soil and ground water contamination in areas receiving heavy applications of biosolid waste amendments.

  8. Effect of soil acidity, soil strength and macropores on root growth and morphology of perennial grass species differing in acid-soil resistance.

    PubMed

    Haling, Rebecca E; Simpson, Richard J; Culvenor, Richard A; Lambers, Hans; Richardson, Alan E

    2011-03-01

    It is unclear whether roots of acid-soil resistant plants have significant advantages, compared with acid-soil sensitive genotypes, when growing in high-strength, acid soils or in acid soils where macropores may allow the effects of soil acidity and strength to be avoided. The responses of root growth and morphology to soil acidity, soil strength and macropores by seedlings of five perennial grass genotypes differing in acid-soil resistance were determined, and the interaction of soil acidity and strength for growth and morphology of roots was investigated. Soil acidity and strength altered root length and architecture, root hair development, and deformed the root tip, especially in acid-soil sensitive genotypes. Root length was restricted to some extent by soil acidity in all genotypes, but the adverse impact of soil acidity on root growth by acid-soil resistant genotypes was greater at high levels of soil strength. Roots reacted to soil acidity when growing in macropores, but elongation through high-strength soil was improved. Soil strength can confound the effect of acidity on root growth, with the sensitivity of acid-resistant genotypes being greater in high-strength soils. This highlights the need to select for genotypes that resist both acidity and high soil strength. © 2010 Blackwell Publishing Ltd.

  9. Selenium biofortification of broccoli and carrots grown in soil amended with Se-enriched hyperaccumulator Stanleya pinnata

    USDA-ARS?s Scientific Manuscript database

    Amending soils with Se-hyperaccumulator plant derived sources of selenium (Se) may be useful for increasing Se content in food crops in Se-deficient regions of the world. In this study, we evaluated total Se and the different chemical species of Se in broccoli and carrots grown in soils amended with...

  10. Oligotyping reveals stronger relationship of organic soil bacterial community structure with N-amendments and soil chemistry in comparison to that of mineral soil at Harvard Forest, MA, USA.

    PubMed

    Turlapati, Swathi A; Minocha, Rakesh; Long, Stephanie; Ramsdell, Jordan; Minocha, Subhash C

    2015-01-01

    The impact of chronic nitrogen amendments on bacterial communities was evaluated at Harvard Forest, Petersham, MA, USA. Thirty soil samples (3 treatments × 2 soil horizons × 5 subplots) were collected in 2009 from untreated (control), low nitrogen-amended (LN; 50 kg NH4NO3 ha(-1) yr(-1)) and high nitrogen-amended (HN; 150 kg NH4NO3 ha(-1) yr(-1)) plots. PCR-amplified partial 16S rRNA gene sequences made from soil DNA were subjected to pyrosequencing (Turlapati et al., 2013) and analyses using oligotyping. The parameters M (the minimum count of the most abundant unique sequence in an oligotype) and s (the minimum number of samples in which an oligotype is expected to be present) had to be optimized for forest soils because of high diversity and the presence of rare organisms. Comparative analyses of the pyrosequencing data by oligotyping and operational taxonomic unit clustering tools indicated that the former yields more refined units of taxonomy with sequence similarity of ≥99.5%. Sequences affiliated with four new phyla and 73 genera were identified in the present study as compared to 27 genera reported earlier from the same data (Turlapati et al., 2013). Significant rearrangements in the bacterial community structure were observed with N-amendments revealing the presence of additional genera in N-amended plots with the absence of some that were present in the control plots. Permutational MANOVA analyses indicated significant variation associated with soil horizon and N treatment for a majority of the phyla. In most cases soil horizon partitioned more variation relative to treatment and treatment effects were more evident for the organic (Org) horizon. Mantel test results for Org soil showed significant positive correlations between bacterial communities and most soil parameters including NH4 and NO3. In mineral soil, correlations were seen only with pH, NH4, and NO3. Regardless of the pipeline used, a major hindrance for such a study remains to be the lack

  11. Stabilization by hydrophobic protection as a molecular mechanism for organic carbon sequestration in maize-amended rice paddy soils.

    PubMed

    Song, X Y; Spaccini, R; Pan, G; Piccolo, A

    2013-08-01

    The hydrophobic components of soil organic matter (SOM) are reckoned to play an important role in the stabilization of soil organic carbon (SOC). The contribution of hydrophobic substances to SOC sequestration was evaluated in four different paddy soils in the South of China, following a 6-month incubation experiment with maize straw amendments. Soil samples included: a well developed paddy soil (TP) derived from clayey lacustrine deposits in the Tai Lake plain of Jiangsu; an acid clayey paddy soil (RP) derived from red earth in the rolling red soil area of Jiangxi; a weakly developed neutral paddy soil (PP) formed on Jurassic purple shale from Chongq; and a calcic Fluvisol (MS) derived from riverine sediments from a wetland along the Yangtze valley of Anhui, China. The SOC molecular composition after 30 and 180 days of incubation, was determined by off-line thermochemolysis followed by gas chromatography-mass spectrometry analysis. Lignin, lipids and carbohydrates were the predominant thermochemolysis products released from the treated soils. A selective preservation of hydrophobic OM, including lignin and lipids, was shown in maize amended soils with prolonged incubation. The decomposition of lignin and lipids was significantly slower in the TP and RP soils characterized by a larger content of extractable iron oxyhydrates (Fed) and lower pH. The overall increase in hydrophobic substances in maize incubated samples was correlated, positively, with total content of clay and Fed, and, negatively, with soil pH. Moreover, yields of both lignin and lipid components showed a significant relationship with SOC increase after incubation. These findings showed that the larger the lipid and lignin content of SOM, the greater was the stability of SOC, thereby suggesting that OM hydrophobic components may have an essential role in controlling the processes of OC sequestration in paddy soils of South China. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Impact of Amendments on the Physical Properties of Soil under Tropical Long-Term No Till Conditions.

    PubMed

    Carmeis Filho, Antonio C A; Crusciol, Carlos A C; Guimarães, Tiara M; Calonego, Juliano C; Mooney, Sacha J

    2016-01-01

    Tropical regions have been considered the world's primary agricultural frontier; however, some physico-chemical deficiencies, such as low soil organic matter content, poor soil structure, high erodibility, soil acidity, and aluminum toxicity, have affected their productive capacity. Lime and gypsum are commonly used to improve soil chemical fertility, but no information exists about the long-term effects of these products on the physical attributes and C protection mechanisms of highly weathered Oxisols. A field trial was conducted in a sandy clay loam (kaolinitic, thermic Typic Haplorthox) under a no-tillage system for 12 years. The trial consisted of four treatments: a control with no soil amendment application, the application of 2.1 Mg ha-1 phosphogypsum, the application of 2.0 Mg ha-1 lime, and the application of lime + phosphogypsum (2.0 + 2.1 Mg ha-1, respectively). Since the experiment was established in 2002, the rates have been applied three times (2002, 2004, and 2010). Surface liming effectively increased water-stable aggregates > 2.0 mm at a depth of up to 0.2 m; however, the association with phosphogypsum was considered a good strategy to improve the macroaggregate stability in subsoil layers (0.20 to 0.40 m). Consequently, both soil amendments applied together increased the mean weight diameter (MWD) and geometric mean diameter (GMD) in all soil layers, with increases of up to 118 and 89%, respectively, according to the soil layer. The formation and stabilization of larger aggregates contributed to a higher accumulation of total organic carbon (TOC) on these structures. In addition to TOC, the MWD and aggregate stability index were positively correlated with Ca2+ and Mg2+ levels and base saturation. Consequently, the increase observed in the aggregate size class resulted in a better organization of soil particles, increasing the macroporosity and reducing the soil bulk density and penetration resistance. Therefore, adequate soil chemical management

  13. Effects of aging process on adsorption-desorption and bioavailability of fomesafen in an agricultural soil amended with rice hull biochar.

    PubMed

    Khorram, Mahdi Safaei; Lin, Dunli; Zhang, Qian; Zheng, Yuan; Fang, Hua; Yu, Yunlong

    2017-06-01

    Biochar has been introduced as an acceptable soil amendment due to its environmental benefits such as sequestering soil contaminants. However, the aging process in biochar amended soil probably decreases the adsorption capacity of biochar through changing its physico-chemical properties. Adsorption, leaching and bioavailability of fomesafen to corn in a Chinese soil amended by rice hull biochar after 0, 30, 90 and 180days were investigated. Results showed that the addition of 0.5%-2% fresh biochar significantly increases the adsorption of fomesafen 4-26 times compare to unamended soil due to higher SSA of biochar. Biochar amendment also decreases fomesafen concentration in soil pore water by 5%-23% resulting lower risk of the herbicide for cultivated plants. However, the aging process decreased the adsorption capacity of biochar since the adsorption coefficient values which was 1.9-12.4 in 0.5%-2% fresh biochar amended soil, declined to 1.36-4.16, 1.13-2.78 and 0.95-2.31 in 1, 3 and 6-month aged treatments, respectively. Consequently, higher desorption, leaching and bioavailable fraction of fomesafen belonged to 6-month aged treatment. Nevertheless, rice hull biochar was effective for sequestering fomesafen as the adsorption capacity of biochar amended soil after 6months of aging was still 2.5-5 times higher compared to that of unamended soil. Copyright © 2016. Published by Elsevier B.V.

  14. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils

    USDA-ARS?s Scientific Manuscript database

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues relative to an unamended control soil was assessed using Lumbricus terrestris in 4-L soil microcos...

  15. Optimization of typical diffuse herbicide pollution control by soil amendment configurations under four levels of rainfall intensities.

    PubMed

    Ouyang, Wei; Huang, Weijia; Wei, Peng; Hao, Fanghua; Yu, Yongyong

    2016-06-15

    Herbicides are a main source of agricultural diffuse pollution due to their wide application in tillage practices. The aim of this study is to optimize the control efficiency of the herbicide atrazine with the aid of modified soil amendments. The soil amendments were composed of a combination of biochar and gravel. The biochar was created from corn straw with a catalytic pyrolysis of ammonium dihydrogen phosphate. The leaching experiments under four rainfall conditions were measured for the following designs: raw soil, soil amended with gravel, biochar individually and together with gravel. The control efficiency of each design was also identified. With the designed equipment, the atrazine content in the contaminant load layer, gravel substrate layer, biochar amendment layer and soil layer was measured under four types of rainfall intensities (1.25 mm/h, 2.50 mm/h, 5.00 mm/h and 10.00 mm/h). Furthermore, the vertical distribution of atrazine in the soil sections was also monitored. The results showed that the herbicide leaching load increased under the highest rainfall intensity in all designs. The soil with the combination of gravel and biochar provided the highest control efficiency of 87.85% on atrazine when the additional proportion of biochar was 3.0%. The performance assessment under the four kinds of rainfall intensity conditions provided the guideline for the soil amendment configuration. The combination of gravel and biochar is recommended as an efficient method for controlling diffuse herbicide pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Native-plant amendments and topsoil addition enhance soil function in post-mining arid grasslands.

    PubMed

    Kneller, Tayla; Harris, Richard J; Bateman, Amber; Muñoz-Rojas, Miriam

    2018-04-15

    One of the most critical challenges faced in restoration of disturbed arid lands is the limited availability of topsoil. In post-mining restoration, alternative soil substrates such as mine waste could be an adequate growth media to alleviate the topsoil deficit, but these materials often lack appropriate soil characteristics to support the development and survival of seedlings. Thus, addition of exogenous organic matter may be essential to enhance plant survival and soil function. Here, we present a case study in the arid Pilbara region (north-west Western Australia), a resource-rich area subject to intensive mining activities. The main objective of our study was to assess the effects of different restoration techniques such as soil reconstruction by blending available soil materials, sowing different compositions of plant species, and addition of a locally abundant native soil organic amendment (Triodia pungens biomass) on: (i) seedling recruitment and growth of Triodia wiseana, a dominant grass in Australian arid ecosystems, and (ii) soil chemical, physical, and biological characteristics of reconstructed soils, including microbial activity, total organic C, total N, and C and N mineralisation. The study was conducted in a 12-month multifactorial microcosms setting in a controlled environment. Our results showed that the amendment increased C and N contents of re-made soils, but these values were still lower than those obtained in the topsoil. High microbial activity and C mineralisation rates were found in the amended waste that contrasted the low N mineralisation but this did not translate into improved emergence or survival of T. wiseana. These results suggest a short- or medium-term soil N immobilisation caused by negative priming effect of fresh un-composted amendment on microbial communities. We found similar growth and survival rates of T. wiseana in topsoil and a blend of topsoil and waste (50:50) which highlights the importance of topsoil, even in a

  17. Amending soils with sediment material from constructed wetlands increases phosphorus sorption

    NASA Astrophysics Data System (ADS)

    Laakso, Johanna; Uusitalo, Risto; Leppänen, Janette; Yli-Halla, Markku

    2017-04-01

    Sediment of agricultural constructed wetlands (CWs) is comprised of matter eroded from surrounding fields. This material is rich in aluminium (Al) and iron (Fe) (hydr)oxides that have a high affinity for phosphorus (P). Sediment material returned to fields could therefore affect soil P retention characteristics. We incubated a clay soil with a high soil test P (STP, 24 mg PAc l-1; extracted with pH 4.65 ammonium acetate buffer) and a sandy loam with excessive STP (210 mg PAc l-1) for three weeks with increasing amounts of CW sediment: 0, 2, 5, 10 and 50% of the sample volume. After incubation, the soil-sediment mixtures were studied with the quantity/intensity (Q/I) technique, using chemical extractions and by exposing the mixtures to simulated rainfall. Sorption affinity for P regularly increased with increasing the sediment share of the mixtures, the 0% sediment content having the lowest and 50% sediment content the highest P sorption. With 0% sediment application, the value of equilibrium P concentration (EPC0) determined by Q/I technique, was 0.69 and 44.3 mg l-1 for clay soil and sandy loam, respectively. With 2-5% sediment amendment, the EPC0 decreased 13-36% for clay soil and 13-54% for sandy loam. The 50% sediment mixtures had EPC0 of 0.05 mg l-1 for both soils. At a practically feasible sediment addition rate of 5%, dissolved reactive P (DRP) in percolating water from simulated rainfall decreased by 55% in the clay soil and 54% in sandy loam (p<0.001 in both cases). Particulate-P (PP) also showed a decreasing trend with increasing sediment addition rate. Upon prolonged simulated rainfall, the decreasing effect of sediment on DRP and PP declined somewhat. The effects of sediment addition can be attributed partly to increased salt concentrations in the sediment, which have a short-term effect on P mobilisation, but mostly to increased concentrations of Al and Fe (hydr)oxides, increasing long-term P sorption capacity. Amending the soils with sediment material

  18. Potential microbial risk factors related to soil amendments and irrigation water of potato crops.

    PubMed

    Selma, M V; Allende, A; López-Gálvez, F; Elizaquível, P; Aznar, R; Gil, M I

    2007-12-01

    This study assesses the potential microbial risk factors related to the use of soil amendments and irrigation water on potato crops, cultivated in one traditional and two intensive farms during two harvest seasons. The natural microbiota and potentially pathogenic micro-organisms were evaluated in the soil amendment, irrigation water, soil and produce. Uncomposted amendments and residual and creek water samples showed the highest microbial counts. The microbial load of potatoes harvested in spring was similar among the tested farms despite the diverse microbial levels of Listeria spp. and faecal coliforms in the potential risk sources. However, differences in total coliform load of potato were found between farms cultivated in the autumn. Immunochromatographic rapid tests and the BAM's reference method (Bacteriological Analytical Manual; AOAC International) were used to detect Escherichia coli O157:H7 from the potential risk sources and produce. Confirmation of the positive results by polymerase chain reaction procedures showed that the immunochromatographic assay was not reliable as it led to false-positive results. The potentially pathogenic micro-organisms of soil amendment, irrigation water and soil samples changed with the harvest seasons and the use of different agricultural practices. However, the microbial load of the produce was not always influenced by these risk sources. Improvements in environmental sample preparation are needed to avoid interferences in the use of immunochromatographic rapid tests. The potential microbial risk sources of fresh produce should be regularly controlled using reliable detection methods to guarantee their microbial safety.

  19. Phosphorus release behaviors of poultry litter biochar as a soil amendment.

    PubMed

    Wang, Yue; Lin, Yingxin; Chiu, Pei C; Imhoff, Paul T; Guo, Mingxin

    2015-04-15

    Phosphorus (P) may be immobilized and consequently the runoff loss risks be reduced if poultry litter (PL) is converted into biochar prior to land application. Laboratory studies were conducted to examine the water extractability of P in PL biochar and its release kinetics in amended soils. Raw PL and its biochar produced through 400°C pyrolysis were extracted with deionized water under various programs and measured for water extractable P species and contents. The materials were further incubated with a sandy loam at 20 g kg(-1) soil and intermittently leached with water for 30 days. The P release kinetics were determined from the P recovery patterns in the water phase. Pyrolysis elevated the total P content from 13.7 g kg(-1) in raw PL to 27.1 g kg(-1) in PL biochar while reduced the water-soluble P level from 2.95 g kg(-1) in the former to 0.17 g kg(-1) in the latter. The thermal treatment transformed labile P in raw PL to putatively Mg/Ca phosphate minerals in biochar that were water-unextractable yet proton-releasable. Orthophosphate was the predominant form of water-soluble P in PL biochar, with condensed phosphate (e.g., pyrophosphate) as a minor form and organic phosphate in null. Release of P from PL biochar in both water and neutral soils was at a slower and steadier rate over a longer time period than from raw PL. Nevertheless, release of P from biochar was acid-driven and could be greatly promoted by the media acidity. Land application of PL biochar at soil pH-incorporated rates and frequency will potentially reduce P losses to runoffs and minimize the adverse impact of waste application on aquatic environments. Copyright © 2015. Published by Elsevier B.V.

  20. Impact of Amendments on the Physical Properties of Soil under Tropical Long-Term No Till Conditions

    PubMed Central

    Mooney, Sacha J.

    2016-01-01

    Tropical regions have been considered the world’s primary agricultural frontier; however, some physico-chemical deficiencies, such as low soil organic matter content, poor soil structure, high erodibility, soil acidity, and aluminum toxicity, have affected their productive capacity. Lime and gypsum are commonly used to improve soil chemical fertility, but no information exists about the long-term effects of these products on the physical attributes and C protection mechanisms of highly weathered Oxisols. A field trial was conducted in a sandy clay loam (kaolinitic, thermic Typic Haplorthox) under a no-tillage system for 12 years. The trial consisted of four treatments: a control with no soil amendment application, the application of 2.1 Mg ha-1 phosphogypsum, the application of 2.0 Mg ha-1 lime, and the application of lime + phosphogypsum (2.0 + 2.1 Mg ha-1, respectively). Since the experiment was established in 2002, the rates have been applied three times (2002, 2004, and 2010). Surface liming effectively increased water-stable aggregates > 2.0 mm at a depth of up to 0.2 m; however, the association with phosphogypsum was considered a good strategy to improve the macroaggregate stability in subsoil layers (0.20 to 0.40 m). Consequently, both soil amendments applied together increased the mean weight diameter (MWD) and geometric mean diameter (GMD) in all soil layers, with increases of up to 118 and 89%, respectively, according to the soil layer. The formation and stabilization of larger aggregates contributed to a higher accumulation of total organic carbon (TOC) on these structures. In addition to TOC, the MWD and aggregate stability index were positively correlated with Ca2+ and Mg2+ levels and base saturation. Consequently, the increase observed in the aggregate size class resulted in a better organization of soil particles, increasing the macroporosity and reducing the soil bulk density and penetration resistance. Therefore, adequate soil chemical management

  1. Leaching of two fungicides in spent mushroom substrate amended soil: Influence of amendment rate, fungicide ageing and flow condition.

    PubMed

    Álvarez-Martín, Alba; Sánchez-Martín, María J; Ordax, José M; Marín-Benito, Jesús M; Sonia Rodríguez-Cruz, M

    2017-04-15

    A study has been conducted on the leaching of two fungicides, tebuconazole and cymoxanil, in a soil amended with spent mushroom substrate (SMS), with an evaluation of how different factors influence this process. The objective was based on the potential use of SMS as a biosorbent for immobilizing pesticides in vulnerable soils, and the need to know how it could affect the subsequent transport of these retained compounds. Breakthrough curves (BTCs) for 14 C-fungicides, non-incubated and incubated over 30days, were obtained in columns packed with an unamended soil (S), and this soil amended with SMS at rates of 5% (S+SMS5) and 50% (S+SMS50) under saturated and saturated-unsaturated flows. The highest leaching of tebuconazole (>50% of the total 14 C added) was found in S when a saturated water flow was applied to the column, but the percentage of leached fungicide decreased when a saturated-unsaturated flow was applied in both SMS-amended soils. Also a significant decrease in leaching was observed for tebuconazole after incubation in the column, especially in S+SMS50 when both flows were applied. Furthermore, cymoxanil leaching was complete in S and S+SMS when a saturated flow was applied, and maximum peak concentrations were reached at 1pore volume (PV), although BTCs showed peaks with lower concentrations in S+SMS. The amounts of cymoxanil retained only increased in S+SMS when a saturated-unsaturated flow was applied. A more relevant effect of SMS for reducing the leaching of fungicide was observed when cymoxanil was previously incubated in the column, although mineralization was enhanced in this case. These results are of interest for extending SMS application on the control of the leaching of fungicides with different physicochemical characteristics after different ageing times in the soil and water flow conditions applied. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Lead Retention in a Calcareous Soil Influenced by Calcium and Phosphate Amendments

    EPA Science Inventory

    Phosphate amendments in calcareous lead (Pb)-contaminated soils to immobilize Pb may be hindered due to competition of Pb with calcium (Ca) that may inhibit the retention of Pb as a precipitation mechanism. This study explored the retention of Pb in a calcareous soil spiked and ...

  3. Combined Amendments of Nano-hydroxyapatite Immobilized Cadmium in Contaminated Soil-Potato (Solanum tuberosum L.) System.

    PubMed

    Liu, Chang; Wang, Lei; Yin, Jiang; Qi, Lipan; Feng, Yan

    2018-04-01

    The toxicity of cadmium (Cd) has posed major public health concern in crops grown in the Cd-contaminated soils. The effects of five amendments, nano-hydroxyapatite (n-HA) and it combined with lime, zeolite, bone mill and fly ash on Cd immobilization in soils and uptake in potatoes, were investigated in a contaminated soil by pot experiments. The result showed that the applications of combined amendments significantly decreased the bioavailable Cd concentrations extracted by TCLP, DTPA-TEA and MgCl 2 in the contaminated soils, and changed the soluble and exchangeable and specifically sorbed fractions to oxide-bound and organic-bound fractions. Compared to the control group, the concentrations of Cd in the potato tubers grown in n-HA, n-HA + Fly ash, n-HA + Lime, n-HA + Bone mill and n-HA + Zeolite soil were reduced 17.4%, 20.7%, 15.2%, 32.6% and 39.1%, respectively. Nano-hydroxyapatite combined amendments was more effective in reducing bioavailable Cd concentrations and Cd accumulations in potatoes, especially for n-HA + Z.

  4. Phosphorus Amendment Efficacy for In Situ Remediation of Soil Lead Depends on the Bioaccessible Method.

    PubMed

    Obrycki, John F; Basta, Nicholas T; Scheckel, Kirk; Stevens, Brooke N; Minca, Kristen K

    2016-01-01

    A validated method is needed to measure reductions of in vitro bioaccessible (IVBA) Pb in urban soil remediated with amendments. This study evaluated the effect of in vitro extraction solution pH and glycine buffer on bioaccessible Pb in P-treated soils. Two Pb-contaminated soils (790-1300 mg Pb kg), one from a garden and one from a city lot in Cleveland, OH, were incubated in a bench scale experiment for 1 yr. Six phosphate amendments, including bone meal, fish bone, poultry litter, monoammonium phosphate, diammonium phosphate, and triple superphosphate, were added to containers at two application rates. Lead IVBA was assessed using USEPA Method 1340 and three modified versions of this method. Modifications included using solutions with pH 1.5 and 2.5 as well as using solutions with and without 0.4 mol L glycine. Soil amendments were ineffective in reducing IVBA Pb in these soils as measured by pH 1.5 with glycine buffer. The greatest reductions in IVBA Pb, from 5 to 26%, were found using pH 2.5 extractions. Lead mineral results showed several soil amendments promoted Pb phosphate formation, an indicator of remediation success. A significant negative linear relationship between reduction in IVBA Pb and Pb-phosphate formation was found only for pH 2.5 without glycine extraction solution. A modified USEPA Method 1340 without glycine and using pH 2.5 has the potential to predict P soil treatment efficacy and reductions in bioavailable Pb. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Assessing the chemical and biological accessibility of the herbicide isoproturon in soil amended with biochar.

    PubMed

    Sopeña, Fatima; Semple, Kirk; Sohi, Saran; Bending, Gary

    2012-06-01

    There is considerable current interest in using biochar (BC) as a soil amendment to sequester carbon to mitigate climate change. However, the implications of adding BC to agricultural soil for the environmental fate of pesticides remain unclear. In particular, the effect of biochars on desorption behavior of compounds is poorly understood. This study examined the influence of BC on pesticide chemical and biological accessibility using the herbicide isoproturon (IPU). Soils amended with 1% and 2% BC showed enhanced sorption, slower desorption, and reduced biodegradation of IPU. Addition of 0.1% BC had no effect on sorption, desorption or biodegradation of IPU. However, the mineralization of (14)C-IPU was reduced by all BC concentrations, reducing by 13.6%, 40.1% and 49.8% at BC concentrations of 0.1%, 1% and 2% respectively. Further, the ratio of the toxic metabolite 4-isopropyl-aniline to intact IPU was substantially reduced by higher BC concentrations. Hydroxypropyl-β-cyclodextrin (HPCD) extractions were used to estimate the IPU bioaccessibility in the BC-amended soil. Significant correlations were found between HPCD-extracted (14)C-IPU and the IPU desorbed (%) (r(2)=0.8518, p<0.01), and also the (14)C-IPU mineralized (%) (r(2)=0.733; p<0.01) for all BC-amended soils. This study clearly demonstrates how desorption in the presence of BC is intimately related to pesticide biodegradation by the indigenous soil microbiota. BC application to agricultural soils can affect the persistence of pesticides as well as the fate of their degradation products. This has important implications for the effectiveness of pesticides as well as the sequestration of contaminants in soils. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Three-year study of fast-growing trees in degraded soils amended with composts: Effects on soil fertility and productivity.

    PubMed

    Madejón, Paula; Alaejos, Joaquin; García-Álbala, José; Fernández, Manuel; Madejón, Engracia

    2016-03-15

    Currently, worries about the effects of intensive plantations on long-term nutrient supply and a loss of productivity have risen. In this study two composts were added to degraded soils where this type of intensive crops were growing, to avoid the soil fertility decrease and try to increase biomass production. For the experiment, two degraded soils in terms of low organic carbon content and low pH were selected in South-West Spain: La Rábida (RA) and Villablanca (VI) sites. Both study sites were divided into 24 plots. In RA, half of the plots were planted with Populus x canadensis "I-214"; the other half was planted with Eucalyptus globulus. At the VI site, half of the plots were planted with Paulownia fortunei, and the other plots were planted with Eucalyptus globulus. For each tree and site, three treatments were established (two organic composts and a control without compost), with four replications per treatment. The organic amendments were "alperujo" compost, AC, a solid by-product from the extraction of olive oil, and BC, biosolid compost. During the three years of experimentation, samples of soils and plants were analyzed for studying chemical and biochemical properties of soil, plant growth and plant nutritional status and biomass production. The composts increased total organic carbon, water-soluble carbon, nutrients and pH of soil only in the most acidic soil. Soil biochemical quality was calculated with the geometric mean of the enzymatic activities (Dehydrogenase, β-glucosidase, Phosphatase and Urease activities) determined in soils. The results showed a beneficial improvement in comparison with soils without compost. However, the best results were found in the growth and biomass production of the studied trees, especially in Eucalyptus. Nutritional levels of leaves of the trees were, in general, in the normal established range for each species, although no clear effect of the composts was observed. The results of this study justify the addition of

  7. The role of biochar, natural iron oxides, and nanomaterials as soil amendments for immobilizing metals in shooting range soil.

    PubMed

    Rajapaksha, Anushka Upamali; Ahmad, Mahtab; Vithanage, Meththika; Kim, Kwon-Rae; Chang, Jun Young; Lee, Sang Soo; Ok, Yong Sik

    2015-12-01

    High concentration of toxic metals in military shooting range soils poses a significant environmental concern due to the potential release of metals, such as Pb, Cu, and Sb, and hence requires remediation. The current study examined the effectiveness of buffalo weed (Ambrosia trifida L.) biomass and its derived biochars at pyrolytic temperatures of 300 and 700 °C, natural iron oxides (NRE), gibbsite, and silver nanoparticles on metal immobilization together with soil quality after 1-year soil incubation. Destructive (e.g., chemical extractions) and non-destructive (e.g., molecular spectroscopy) methods were used to investigate the immobilization efficacy of each amendment on Pb, Cu, and Sb, and to explore the possible immobilization mechanisms. The highest immobilization efficacy was observed with biochar produced at 300 °C, showing the maximum decreases of bioavailability by 94 and 70% for Pb and Cu, respectively, which were attributed to the abundance of functional groups in the biochar. Biochar significantly increased the soil pH, cation exchange capacity, and P contents. Indeed, the scanning electron microscopic elemental dot mapping and X-ray absorption fine structure spectroscopic (EXAFS) studies revealed associations of Pb with P (i.e., the formation of stable chloropyromorphite [Pb5(PO4)3Cl]) in the biomass- or biochar-amended soils. However, no amendment was effective on Sb immobilization.

  8. Response of N2O emissions to biochar amendment in a cultivated sandy loam soil during freeze-thaw cycles

    PubMed Central

    Liu, Xiang; Wang, Quan; Qi, Zhiming; Han, Jiangang; Li, Lanhai

    2016-01-01

    In the last decade, an increasing number of studies have reported that soil nitrous oxide (N2O) emissions can be reduced by adding biochar. However, the effect of biochar amendment on soil N2O emissions during freeze-thaw cycle (FTC) is still unknown. In this laboratory study, biochar (0%, 2% and 4%, w/w) was added into a cultivated sandy loam soil and then treated with 15 times of FTC (each FTC consisted of freeze at −5/−10 °C for 24 h and thaw at 5/10 °C for 24 h), to test whether biochar can mitigate soil N2O emissions during FTC, and estimate the relationships between N2O emissions and soil inorganic nitrogen contents/microbial biomass content/enzyme activities. The results showed that biochar amendment suppressed soil N2O emissions by 19.9–69.9% as compared to soils without biochar amendment during FTC. However, N2O emissions were only significantly correlated to soil nitrate nitrogen (NO3−-N) contents, which decreased after biochar amendment, indicating that the decreased soil nitrification by adding biochar played an important role in mitigating N2O emissions during FTC. Further studies are needed to estimate the effectiveness of biochar amendment on reducing freeze-thaw induced N2O emissions from different soils under field conditions. PMID:27748462

  9. Soil amendments and planting techniques : campsite restoration in the Eagle Cap Wilderness, Oregon

    Treesearch

    David N. Cole; David R. Spildie

    2000-01-01

    Results of the first three years of revegetation research on closed wilderness campsites are described. Experimental treatments involved soil scarification, an organic soil amendment (a mix of locally collected organic materials and peat moss and an inoculation of native undisturbed soil), an organic matter and composted sewage sludge treatment and surface application...

  10. Molybdenum uptake by forage crops grown on sewage sludge -- Amended soils in the field and greenhouse

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McBride, M.B.; Richards, B.K.; Steenhuis, T.

    2000-06-01

    Molybdenum (Mo) is a plant-available element in soils that can adversely affect the health of farm animals. There is a need for more information on its uptake into forage crops from waste materials, such as sewage sludge, applied to agricultural land. Field and greenhouse experiments with several crops grown on long-term sewage sludge-amended soils as well as soils recently amended with dewatered (DW) and alkaline-stabilized (ALK) sludges indicated that Mo supplied from sludge is readily taken up by legumes in particular. Excessive uptake into red clover (Trifolium pratense L.) was seen in a soil that had been heavily amended withmore » sewage sludge 20 yr earlier, where the soil contained about 3 mg Mo/kg soil, three times the background soil concentration. The greenhouse and field studies indicated that Mo can have a long residual availability in sludge-amended soils. The effect of sludge application was to decrease Cu to Mo ratios in legume forages, canola (Brassica napus var. napus) and soybeans [Glycine max (L.) Merr.] below the recommended limit of 2:1 for ruminant diets, a consequence of high bioavailability of Mo and low uptake of Cu added in sludge. Molybdenum uptake coefficients (UCs) for ALK sludge were higher than for DW sludge, presumably due to the greater solubility of Mo measured in the more alkaline sludges and soils. Based on these UCs, it is tentatively recommended that cumulative Mo loadings on forages grown on nonacid soils should not exceed 1.0 kg/ha from ALK sludge or 4.0 kg/ha from DW sludge.« less

  11. Global warming potential of manure amended soils under rice-wheat system in the Indo-Gangetic plains

    NASA Astrophysics Data System (ADS)

    Bhatia, A.; Pathak, H.; Jain, N.; Singh, P. K.; Singh, A. K.

    Use of organic amendments such as farmyard manure (FYM), green manure (GM) and crop residues is important to improve soil health and reduce the dependence on synthetic chemical fertilizer. However, these organic amendments also effect the emissions of greenhouse gas (GHG) from soil. Influence of different organic amendments on emissions of GHG from soil and their global warming potential (GWP) was studied in a field experiment in rice-wheat cropping system of Indo-Gangetic plains (IGP). There was 28% increase in CH 4 emissions on addition of 25% N through Sesbania GM along with urea compared to urea alone. Substitution of 100% inorganic N by organic sources lead to a 60% increase in CH 4 emissions. The carbon equivalent emission from rice-wheat systems varied between 3816 and 4886 kg C equivalent ha -1 depending upon fertilizer and organic amendment. GWP of rice-wheat system increased by 28% on full substitution of organic N by chemical N. However, the C efficiency ratios of the GM and crop residue treatments were at par with the recommended inorganic fertilizer treatment. Thus use of organic amendments along with inorganic fertilizer increases the GWP of the rice-wheat system but may improve the soil fertility status without adversely affecting the C efficiency ratio. However, the trade-off between improved yield and soil health versus GHG emissions should be taken into account while promoting the practice of farming with organic residues substitution for mineral fertilizer.

  12. The Use of Phosphate Amendments for Chemical Immobilization of Uranium in Contaminated Soil.

    NASA Astrophysics Data System (ADS)

    Baker, M.; Coutelot, F.; Seaman, J. C.

    2017-12-01

    Past Department of Energy (DOE) production of nuclear materials has resulted in uranium (U) contaminated soil and groundwater posing a significant risk to the environment and human health. In situ remediation strategies are typically less expensive and rely on the introduction of chemical additives in order to reduce contaminant migration and ultimately the associated exposure hazard. Phosphate addition to U-contaminated subsurface environments has been proposed as a U remediation strategy. Saturated and unsaturated batch experiments were performed to investigate the ability of three different phosphate source treatments: hydroxyapatite (HA), phytic acid (IP6) and sodium tripolyphosphate (TPP) to chemically immobilize U in contaminated Savannah River Site (SRS) soil (2,040 mg U/kg soil). Amendment treatments ranged from 925 to 4620 mg P /kg soil. Unsaturated test samples were equilibrated for 3 weeks at 60% of the soil's field capacity, followed by pore-water extraction by centrifugation to provide an indication of the remaining mobile U fraction. Saturated batch experiments were equilibrated on an orbital shaker for 30 days under both oxic and anoxic conditions, with aliquots taken at specific intervals for chemical analysis. In the saturated microcosms, HA decreased the mobile U concentration by 98% in both redox environments and at all treatment levels. IP6 and TPP were able to decrease the soluble U concentration at low treatment levels, but tended to release U at higher treatment levels compared to the control. Unsaturated microcosms also showed HA to be the most effective treatment for immobilizing U, but IP6 and TPP were as effective as HA at the lowest treatment level. The limited contaminant immobilization following TPP and IP6 amendments correlated with the dispersion of organic matter and organo-mineral colloids. For both experiment types, TPP and IP6 samples showed a very limited ortho-phosphate (PO4-) in the solution, indicating the slow mineralization

  13. Typical agricultural diffuse herbicide sorption with agricultural waste-derived biochars amended soil of high organic matter content.

    PubMed

    Ouyang, Wei; Zhao, Xuchen; Tysklind, Mats; Hao, Fanghua

    2016-04-01

    Biochar application has been identified as the effective soil amendment and the materials to control the diffuse herbicide pollution. The atrazine was selected as the typical diffuse herbicide pollutant as the dominant proportion in applications. The biochar treated from four types of crops biomass were added to soil with high organic matter content. The basic sorption characteristics of biocahrs from corn cob (CC), corn stalk (CS), soybean straw (SS), rice straw (RS) and corn stalk paralyzed with 5% of ammonium dihydrogen phosphate (ACS) were analyzed, along with the comparison of the sorption difference of the raw soil and soil amended with biochars at four levels of ratio (0.5%, 1.0%, 3.0% and 5.0%). It was found that the linear distribution isotherm of raw soil was much effective due to the high organic matter background concentration. The addition of five types of biochars under two kinds of initial atrazine concentration (1 mg/L and 20 mg/L) demonstrated the sorption variances. Results showed the soil amended with RS and CS biochar had the biggest removal rate in four regular biochars and the removal rate of the ACS was the biggest. The sorption coefficient and the normalized sorption coefficient from Freundlich modeling presented the isothermal sorption characteristics of atrazine with soil of high organic matter content. The normalized sorption coefficient increased with the equilibrium concentration decreased in the biochar amended soil, which indicated the sorption performance will be better due to the low atrazine concentration in practice. Results showed that biochar amendment is the effective way to prevent leakage of diffuse herbicide loss. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Linear combination fitting results for lead speciation in amended soils

    EPA Pesticide Factsheets

    Table listing the location, amendment type, distribution (percentage) of lead phases identified, and fitting error (R-factor). BM=bone meal, FB=fish bone, DAP=diammonium phosphate, MAP=monoammonium phosphate, TSP=triple super phosphate, PL=poultry litterThis dataset is associated with the following publication:Obrycki, J., N. Basta, K. Scheckel , B. Stevens, and K. Minca. Phosphorus Amendment Efficacy for In Situ Remediation of Soil Lead Depends on the Bioaccessible Method. Elizabeth Guertal, David Myroid, and C. Wayne Smith JOURNAL OF ENVIRONMENTAL QUALITY. American Society of Agronomy, MADISON, WI, USA, 45(1): 37-44, (2016).

  15. Determination of fluorotelomer alcohols and their degradation products in biosolids-amended soils and plants using ultra-high performance liquid chromatography tandem mass spectrometry.

    PubMed

    Zhang, Hongna; Wen, Bei; Hu, Xiaoyu; Wu, Yali; Luo, Lei; Chen, Zien; Zhang, Shuzhen

    2015-07-24

    Degradation of fluorotelomer alcohols (FTOHs) was recognized as an additional source of perfluorocarboxylic acids (PFCAs). Quantification of FTOHs and their degradation products can help shed light on the sources and fates of PFCAs in the environment. In this study, an analytical method was developed for the determination of 6:2 and 8:2 FTOHs, and their degradation products of poly- and perfluorinated acids, including fluorotelomer saturated and unsaturated carboxylic acids (FTCAs and FTUCAs), secondary polyfluorinated alcohols and PFCAs in biosolids-amended soils and plants using ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The extract efficiencies of different methods including ethyl acetate and methanol (MeOH) for FTOHs and acetonitrile, MeOH, methyl tert-butyl ether (MTBE), NaOH-MeOH and NaOH-MTBE for poly- and perfluorinated acids were tested. The results showed that 6:2 and 8:2 FTOHs and their degradation products could be simultaneously and satisfactorily extracted by MeOH, cleaned up by Envi-Carb graphitized carbon and solid phase extraction, respectively, and determined by UPLC-MS/MS separately. NaOH in the extractant caused the conversion of 6:2 FTCA and 8:2 FTCA into the corresponding FTUCAs. The selected methods have matrix recoveries ranged from 52% to 102%, and detection limits of 0.01-0.46ng/g dry weight for FTOHs and their degradation products in soil and plant. The optimized method was applied successfully to quantify FTOHs and their degradation products in two biosolids-amended soils and plants. The total concentrations of FTOHs in the soils were 44.1±5.8 and 82.6±7.1ng/g, and in plants tissues 3.58±0.25 and 8.33±0.66ng/g. The total concentrations of poly- and perfluorinated acids in the soils were 168.0±13.2 and 349.6±11.2ng/g, and in plants tissues 78.0±6.4 and 75.5±5.3ng/g. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Polynuclear aromatic hydrocarbon uptake by carrots grown in sludge-amended soil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wild, S.R.; Jones, K.C.

    The uptake of polynuclear aromatic hydrocarbons (PAHs) from sewage sludge-amended soils by carrots (Daucus carota) was investigated. Carrots were grown in control soils and soils amended with three sludge application rates, 15, 55, and 180 t/ha. Applied sludge contained 17.2 mg [summation]PAH/kg, a concentration typical for a sludge derived from a rural area. Carrot foliage, root peels and root cores were analyzed for 15 PAH compounds. Carrots foliage PAH concentrations were unaffected by sludge applications (PAH loadings), but root peel PAH concentrations increased to a plateau concentration with increasing soil PAH levels. Low molecular weight PAH compounds dominate dindividual componentsmore » of the [summation]PAH load in the root tissues. The PAH concentrations detected in the root peels were all significantly lower than in the foliage, which receives PAH inputs from the atmosphere. Carrot core [summation]PAH concentrations were unaffected by sludge application, implying little or no transfer of PAHs from the peels to the core. About 70% of the PAH burden found in carrots was associated with the peels. Fresh weight carrot core concentrations were all <4.2 [mu]g/kg. Overall, this investigation suggests that the risks posed to human health by PAHs applied in sewage sludge to arable soils are minimal.« less

  17. Nitrification of archaeal ammonia oxidizers in acid soils is supported by hydrolysis of urea

    PubMed Central

    Lu, Lu; Han, Wenyan; Zhang, Jinbo; Wu, Yucheng; Wang, Baozhan; Lin, Xiangui; Zhu, Jianguo; Cai, Zucong; Jia, Zhongjun

    2012-01-01

    The hydrolysis of urea as a source of ammonia has been proposed as a mechanism for the nitrification of ammonia-oxidizing bacteria (AOB) in acidic soil. The growth of Nitrososphaera viennensis on urea suggests that the ureolysis of ammonia-oxidizing archaea (AOA) might occur in natural environments. In this study, 15N isotope tracing indicates that ammonia oxidation occurred upon the addition of urea at a concentration similar to the in situ ammonium content of tea orchard soil (pH 3.75) and forest soil (pH 5.4) and was inhibited by acetylene. Nitrification activity was significantly stimulated by urea fertilization and coupled well with abundance changes in archaeal amoA genes in acidic soils. Pyrosequencing of 16S rRNA genes at whole microbial community level demonstrates the active growth of AOA in urea-amended soils. Molecular fingerprinting further shows that changes in denaturing gradient gel electrophoresis fingerprint patterns of archaeal amoA genes are paralleled by nitrification activity changes. However, bacterial amoA and 16S rRNA genes of AOB were not detected. The results strongly suggest that archaeal ammonia oxidation is supported by hydrolysis of urea and that AOA, from the marine Group 1.1a-associated lineage, dominate nitrification in two acidic soils tested. PMID:22592820

  18. Nitrification of archaeal ammonia oxidizers in acid soils is supported by hydrolysis of urea.

    PubMed

    Lu, Lu; Han, Wenyan; Zhang, Jinbo; Wu, Yucheng; Wang, Baozhan; Lin, Xiangui; Zhu, Jianguo; Cai, Zucong; Jia, Zhongjun

    2012-10-01

    The hydrolysis of urea as a source of ammonia has been proposed as a mechanism for the nitrification of ammonia-oxidizing bacteria (AOB) in acidic soil. The growth of Nitrososphaera viennensis on urea suggests that the ureolysis of ammonia-oxidizing archaea (AOA) might occur in natural environments. In this study, (15)N isotope tracing indicates that ammonia oxidation occurred upon the addition of urea at a concentration similar to the in situ ammonium content of tea orchard soil (pH 3.75) and forest soil (pH 5.4) and was inhibited by acetylene. Nitrification activity was significantly stimulated by urea fertilization and coupled well with abundance changes in archaeal amoA genes in acidic soils. Pyrosequencing of 16S rRNA genes at whole microbial community level demonstrates the active growth of AOA in urea-amended soils. Molecular fingerprinting further shows that changes in denaturing gradient gel electrophoresis fingerprint patterns of archaeal amoA genes are paralleled by nitrification activity changes. However, bacterial amoA and 16S rRNA genes of AOB were not detected. The results strongly suggest that archaeal ammonia oxidation is supported by hydrolysis of urea and that AOA, from the marine Group 1.1a-associated lineage, dominate nitrification in two acidic soils tested.

  19. Long-term sustainability of metal immobilization by soil amendments: cyclonic ashes versus lime addition.

    PubMed

    Ruttens, A; Adriaensen, K; Meers, E; De Vocht, A; Geebelen, W; Carleer, R; Mench, M; Vangronsveld, J

    2010-05-01

    A soil column leaching experiment was used to gain insight into the long-term metal immobilization capacity of cyclonic ashes (CAH) compared to lime (LIME). Twenty six years of rainfall were simulated. Initially, all amended soils were brought to an equal soil pH. This was done to obtain optimal conditions for the detection of metal immobilization mechanisms different from just a pH effect. During the simulation period, soil pH in all treatments decreased in parallel. However, the evolution of metal mobility and phytoavailability showed a clearly distinct pattern. The strong reduction in metal immobilizing efficiency observed in the lime treatment at the end of the simulation period was much less pronounced, or even absent, in the CAH treatments. Moreover, metal accumulation in plants grown on the CAH amended soil was significantly lower compared to the untreated and the lime treated soil. CAH + SS treatment delivered the strongest reductions in metal mobility and bioavailability. Copyright 2009 Elsevier Ltd. All rights reserved.

  20. Evaluating phytoextraction efficiency of two high-biomass crops after soil amendment and inoculation with rhizobacterial strains.

    PubMed

    Vanessa, Álvarez-López; Ángeles, Prieto-Fernández; Sergio, Roiloa; Beatriz, Rodríguez-Garrido; Rolf, Herzig; Markus, Puschenreiter; Susan, Kidd Petra

    2017-03-01

    We evaluated the effect of compost amendment and/or bacterial inoculants on the growth and metal accumulation of Salix caprea (clone BOKU 01 AT-004) and Nicotiana tabacum (in vitro-bred clone NBCu10-8). Soil was collected from an abandoned Pb/Zn mine and rhizobacterial inoculants were previously isolated from plants growing at the same site. Plants were grown in untreated or compost-amended (5% w/w) soil and were inoculated with five rhizobacterial strains. Non-inoculated plants were also established as a control. Compost addition increased the shoot DW yield of N. tabacum but not S. caprea, while it decreased soil metal availability and lowered shoot Cd/Zn concentrations in tobacco plants. Compost amendment enhanced the shoot Cd/Zn removal due to the growth promotion of N. tabacum or to the increase in metal concentration in S. caprea leaves. Bacterial inoculants increased photosynthetic efficiency (particularly in N. tabacum) and sometimes modified soil metal availability, but this did not lead to a significant increase in Cd/Zn removal. Compost amendment was more effective in improving the Cd and Zn phytoextraction efficiency than bioaugmentation.

  1. Fate of Escherichia coli O157: H7 in agricultural soils amended with different organic fertilizers.

    PubMed

    Yao, Zhiyuan; Yang, Li; Wang, Haizhen; Wu, Jianjun; Xu, Jianming

    2015-10-15

    Five organic fertilizers (vermicompost, pig manure, chicken manure, peat and oil residue) were applied to agricultural soils to study their effects on the survival of Escherichia coli O157:H7 (E. coli O157:H7). Results showed that E. coli O157:H7 survival changed greatly after organic fertilizers application, with shorter td values (survival time needed to reach the detection limit of 100 CFU g(-1)) (12.57±6.57 days) in soils amended with chicken manure and the longest (25.65±7.12 days) in soils amended with pig manure. Soil pH, EC and free Fe/Al (hydro) oxides were significant explanatory factors for E. coli O157:H7 survival in the original soils. Soil constituents (minerals and organic matter) and changes in their surface charges with pH increased the effect of soil pH on E. coli O157:H7 survival. However, electrical conductivity played a more important role in regulating E. coli O157:H7 survival in fertilizer-amended soils. This study highlighted the importance of choosing appropriate organic fertilizers in the preharvest environment to reduce food-borne bacterial contamination. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Seasonal dynamics of CO2 efflux in soils amended with composted and thermally-dried sludge as affected by soil tillage systems in a semi-arid agroecosystem

    NASA Astrophysics Data System (ADS)

    García-Gil, Juan Carlos; Soler-Rovira, Pedro; López-de-Sa, Esther G.; Polo, Alfredo

    2014-05-01

    In semi-arid agricultural soils, seasonal dynamic of soil CO2 efflux (SCE) is highly variable. Based on soil respiration measurements the effects of different management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) was investigated in a long-term field experiment (28 years) conducted on a sandy-loam soil at the experimental station 'La Higueruela' (40o 03'N, 4o 24'W). Both organic amendments were applied at a rate of 30 Mg ha-1 prior to tillage practices. Unamended soils were used as control for each tillage system. SCE was moderate in late spring (2.2-11.8 μmol CO2 m-2 s-1) when amendments were applied and tillage was performed, markedly decreased in summer (0.4-3.2 μmol CO2 m-2 s-1), following a moderate increase in autumn (3.4-14.1 μmol CO2 m-2 s-1), rising sharply in October (5.6-39.8 μmol CO2 m-2 s-1 ). In winter, SCE was low (0.6-6.5 μmol CO2 m-2 s-1). In general, SCE was greater in chisel and moldboard tilled soils, and in CS and particularly TSS-amended soils, due to the addition of labile C with these amendments, meanwhile no-tillage soils exhibited smaller increases in C efflux throughout the seasons. Soil temperature controlled the seasonal variations of SCE. In summer, when drought occurs, a general decrease of SCE was observed due to a deficit in soil water content. After drought period SCE jumped to high values in response to rain events ('Birch effect') that changed soil moisture conditions. Soil drying in summer and rewetting in autumn may promotes some changes on the structure of soil microbial community, affecting associated metabolic processes, and enhancing a rapid mineralization of water-soluble organic C compounds and/or dead microbial biomass that acts as an energy source for soil microorganisms. To assess the effects of tillage and amendments on SCE, Q10 values were calculated. Data were grouped into three groups according to soil moisture (0

  3. Valorization of a treated soil via amendments: fractionation and oral bioaccessibility of Cu, Ni, Pb, and Zn.

    PubMed

    Zagury, Gerald J; Rincon Bello, Jhony A; Guney, Mert

    2016-04-01

    The present study aims to transform a treated soil (TS) into a more desirable resource by modifying physico-chemical properties via amendments while reducing toxic metals' mobility and oral bioaccessibility. A hydrocarbon-contaminated soil submitted to treatment (TS) but still containing elevated concentrations of Cu, Ni, Pb, and Zn has been amended with compost, sand, and Al2(SO4)3 to render it usable for horticulture. Characterization and sequential extraction were performed for TS and four amended mixtures (AM1-4). P and K availability and metal bioaccessibility were investigated in TS and AM2. Amendment improved soil properties for all mixtures and yielded a usable product (AM2 20 % TS, 49 % compost, 30 % sand, 1 % Al2(SO4)3) satisfying regulatory requirements except for Pb content. In particular, AM2 had improved organic matter (OM) and cation exchange capacity (CEC), highly increased P and K availability, and reduced total metal concentrations. Furthermore, amendment decreased metal mobile fraction likely to be plant-available (in mg kg(-1), assumed as soluble/exchangeable + carbonates fractions). For AM2, estimated Pb bioavailability decreased from 1.50 × 10(3) mg kg(-1) (TS) to 238 mg kg(-1) (52.4 % (TS) to 34.2 %). Bioaccessible concentrations of Cu, Ni, and Zn (mg kg(-1)) were lower in AM2 than in TS, but there was no significant decrease for Pb. The results suggest that amendment improved soil by modifying its chemistry, resulting in lower metal mobile fraction (in %, for Cu and Zn) and bioaccessibility (in %, for Cu only). Amending soils having residual metal contamination can be an efficient valorization method, indicating potential for reducing treatment cost and environmental burden by rendering disposal/additional treatment unnecessary. Further studies including plant bioavailability are recommended to confirm results.

  4. Potential risk of biochar-amended soil to aquatic systems: an evaluation based on aquatic bioassays.

    PubMed

    Bastos, A C; Prodana, M; Abrantes, N; Keizer, J J; Soares, A M V M; Loureiro, S

    2014-11-01

    It is vital to address potential risks to aquatic ecosystems exposed to runoff and leachates from biochar-amended soils, before large scale applications can be considered. So far, there are no established approaches for such an assessment. This study used a battery of bioassays and representative aquatic organisms for assessing the acute toxicity of water-extractable fractions of biochar-amended soil, at reported application rates (80 t ha(-1)). Biochar-amended aqueous soil extracts contained cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As) and mercury (Hg) (Σmetals 96.3 µg l(-1)) as well as the 16 priority PAHs defined by the U.S. Environmental Protection Agency (Σ16PAHs 106 ng l(-1)) at contents in the range of current EU regulations for surface waters. Nevertheless, acute exposure to soil-biochar (SB) extracts resulted in species-specific effects and dose-response patterns. While the bioluminescent marine bacterium Vibrio fischeri was the most sensitive organism to aqueous SB extracts, there were no effects on the growth of the microalgae Pseudokirchneriella subcapitata. In contrast, up to 20 and 25% mobility impairment was obtained for the invertebrate Daphnia magna upon exposure to 50 and 100% SB extract concentrations (respectively). Results suggest that a battery of rapid and cost-effective aquatic bioassays that account for ecological representation can complement analytical characterization of biochar-amended soils and risk assessment approaches for surface and groundwater protection.

  5. Exposure of agricultural crops to nanoparticle CeO2 in biochar-amended soil.

    PubMed

    Servin, Alia D; De la Torre-Roche, Roberto; Castillo-Michel, Hiram; Pagano, Luca; Hawthorne, Joseph; Musante, Craig; Pignatello, Joseph; Uchimiya, Minori; White, Jason C

    2017-01-01

    Biochar is seeing increased usage as an amendment in agricultural soils but the significance of nanoscale interactions between this additive and engineered nanoparticles (ENP) remains unknown. Corn, lettuce, soybean and zucchini were grown for 28 d in two different soils (agricultural, residential) amended with 0-2000 mg engineered nanoparticle (ENP) CeO 2  kg -1 and biochar (350 °C or 600 °C) at application rates of 0-5% (w/w). At harvest, plants were analyzed for biomass, Ce content, chlorophyll and lipid peroxidation. Biomass from the four species grown in residential soil varied with species and biochar type. However, biomass in the agricultural soil amended with biochar 600 °C was largely unaffected. Biochar co-exposure had minimal impact on Ce accumulation, with reduced or increased Ce content occurring at the highest (5%) biochar level. Soil-specific and biochar-specific effects on Ce accumulation were observed in the four species. For example, zucchini grown in agricultural soil with 2000 mg CeO 2  kg -1 and 350 °C biochar (0.5-5%) accumulated greater Ce than the control. However, for the 600 °C biochar, the opposite effect was evident, with decreased Ce content as biochar increased. A principal component analysis showed that biochar type accounted for 56-99% of the variance in chlorophyll and lipid peroxidation across the plants. SEM and μ-XRF showed Ce association with specific biochar and soil components, while μ-XANES analysis confirmed that after 28 d in soil, the Ce remained largely as CeO 2 . The current study demonstrates that biochar synthesis conditions significantly impact interactions with ENP, with subsequent effects on particle fate and effects. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  6. Corn grain yield and soil properties after 10 years of broiler litter amendment

    USDA-ARS?s Scientific Manuscript database

    Use of broiler litter nutrients for crop production benefits crops, soils, and aids in disposing manure. Understanding corn (Zea mays L.) grain production and soil properties resulting from long-term poultry litter amendment helps establish a sustainable animal manure based corn production with low ...

  7. Impacts of Activated Carbon Amendment on Hg Methylation, Demethylation and Microbial Activity in Marsh Soils

    NASA Astrophysics Data System (ADS)

    Gilmour, C. C.; Ghosh, U.; Santillan, E. F. U.; Soren, A.; Bell, J. T.; Butera, D.; McBurney, A. W.; Brown, S.; Henry, E.; Vlassopoulos, D.

    2015-12-01

    In-situ sorbent amendments are a low-impact approach for remediation of contaminants in sediments, particular in habitats like wetlands that provide important ecosystem services. Laboratory microcosm trials (Gilmour et al. 2013) and early field trials show that activated carbon (AC) can effectively increase partitioning of both inorganic Hg and methylmercury to the solid phase. Sediment-water partitioning can serve as a proxy for Hg and MeHg bioavailability in soils. One consideration in using AC in remediation is its potential impact on organisms. For mercury, a critical consideration is the potential impact on net MeHg accumulation and bioavailability. In this study, we specifically evaluated the impact of AC on rates of methylmercury production and degradation, and on overall microbial activity, in 4 different Hg-contaminated salt marsh soils. The study was done over 28 days in anaerobic, sulfate-reducing slurries. A double label of enriched mercury isotopes (Me199Hg and inorganic 201Hg) was used to separately follow de novo Me201Hg production and Me199Hg degradation. AC amendments decreased both methylation and demethylation rate constants relative to un-amended controls, but the impact on demethylation was stronger. The addition of 5% (dry weight) regenerated AC to soil slurries drove demethylation rate constants to nearly zero; i.e. MeHg sorption to AC almost totally blocked its degradation. The net impact was increased solid phase MeHg concentrations in some of the soil slurries with the highest methylation rate constants. However, the net impact of AC amendments was to increase MeHg (and inorganic Hg) partitioning to the soil phase and decrease concentrations in the aqueous phase. AC significantly decreased aqueous phase inorganic Hg and MeHg concentrations after 28 days. Overall, the efficacy of AC in reducing aqueous MeHg was highest in the soils with the highest MeHg concentrations. The AC addition did not significantly impact microbial activity, as

  8. Biochar amendment reduces paddy soil nitrogen leaching but increases net global warming potential in Ningxia irrigation, China.

    PubMed

    Wang, Yongsheng; Liu, Yansui; Liu, Ruliang; Zhang, Aiping; Yang, Shiqi; Liu, Hongyuan; Zhou, Yang; Yang, Zhengli

    2017-05-09

    The efficacy of biochar as an environmentally friendly agent for non-point source and climate change mitigation remains uncertain. Our goal was to test the impact of biochar amendment on paddy rice nitrogen (N) uptake, soil N leaching, and soil CH 4 and N 2 O fluxes in northwest China. Biochar was applied at four rates (0, 4.5, 9 and13.5 t ha -1 yr -1 ). Biochar amendment significantly increased rice N uptake, soil total N concentration and the abundance of soil ammonia-oxidizing archaea (AOA), but it significantly reduced the soil NO 3 - -N concentration and soil bulk density. Biochar significantly reduced NO 3 - -N and NH 4 + -N leaching. The C2 and C3 treatments significantly increased the soil CH 4 flux and reduced the soil N 2 O flux, leading to significantly increased net global warming potential (GWP). Soil NO 3 - -N rather than NH 4 + -N was the key integrator of the soil CH 4 and N 2 O fluxes. Our results indicate that a shift in abundance of the AOA community and increased rice N uptake are closely linked to the reduced soil NO 3 - -N concentration under biochar amendment. Furthermore, soil NO 3 - -N availability plays an important role in regulating soil inorganic N leaching and net GWP in rice paddies in northwest China.

  9. Short-term effects of sugarcane waste products from ethanol production plant as soil amendments on sugarcane growth and metal stabilization.

    PubMed

    Akkajit, Pensiri; DeSutter, Thomas; Tongcumpou, Chantra

    2013-05-01

    Numerous waste products have been widely studied and used as soil amendments and metal immobilizing agents. Waste utilization from ethanol production processes as soil amendments is one of the most promising and sustainable options to help utilize materials effectively, reduce waste disposal, and add value to byproducts. As a consequence, this present work carried out a four-month pot experiment of sugarcane (Saccharum officinarum L.) cultivation in Cd and Zn contaminated soil to determine the effect of three sugarcane waste products (boiler ash, filter cake and vinasse) as soil amendment on sugarcane growth, metal translocation and accumulation in sugarcane, and fractionation of Cd and Zn in soil by the BCR sequential extraction. Four treatments were tested: (1) non-amended soil; (2) 3% w/w boiler ash; (3) 3% w/w filter cake; and (4) a combination of 1.5% boiler ash and 1.5% vinasse (w/w). Our findings showed the improved biomass production of sugarcanes; 6 and 3-fold higher for the above ground parts (from 8.5 to 57.6 g per plant) and root (from 2.1 to 6.59 g per plant), respectively, as compared to non-amended soil. Although there was no significant difference in Cd and Zn uptake in sugarcane (mg kg(-1)) between the non-amended soil and the treated soils (0.44 to 0.52 mg Cd kg(-1) and 39.9 to 48.1 mg Zn kg(-1), respectively), the reduction of the most bioavailable Cd concentration (BCR1 + 2) in the treated soils (35.4-54.5%) and the transformation of metal into an insoluble fraction (BCR3) highlighted the beneficial effects of sugarcane waste-products in promoting the sugarcane growth and Cd stabilization in soil.

  10. Achilles heel of environmental risk from recycling of sludge to soil as amendment: A summary in recent ten years (2007-2016).

    PubMed

    Liu, Hong-Tao

    2016-10-01

    Recycling sludge as a soil amendment has both positive and negative effects because of its enrichment in both nutrients and contaminants. So far, the negative effect has to be extensively investigated that the severities of different types of contaminants also remain unclear. The environmental behavior and risk of organic contaminant and pharmaceuticals, heavy metal and salt as well as pathogenic microorganisms brought by sludge amendment are summarized and discussed here. Organic contaminants and pharmaceuticals are typically found at low concentrations in sludge, the risks from sludge-amended soil decrease over time owing to its biodegradability. On the other hand, application of sludge generally increases soil salinity, which may cause physiological damage to plants grown in sludge-amended soil. In some extent, this negative effect can be alleviated by means of dilution; however, greater attention should be paid to long term increasing possible risk of eutrophication. Heavy metal (particularly of mobile heavy metals, such as Cd) with high concentrations in sludge and soil receiving considerable sludge can cause its incremental abundance in soil and crop contamination, further posing risks to humans, but most cases showed that there remained not excessive in heavy metal caused by sludge amendment. It is worth noting that increasing soil organic matter content may reduce transfer of heavy metal from soil to crops, but not restrict its uptake by crops at all. Combined literature together, it is summarized that heavy metal becomes a relatively severe bottleneck in recycling of sludge as soil amendment due to its non-biodegradability and potential damage to health by adventuring contamination from agricultural products. Particular attention should therefore be paid to long term monitoring the change of heavy metals concentration in sludge amended soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. The roles of nematodes in nitrogen and phosphorous availability, plant uptake and growth in organically amended soils

    NASA Astrophysics Data System (ADS)

    Gebremikael, Mesfin; Buchan, David; De Neve, Stefaan

    2017-04-01

    Several studies have shown that soil biota contributes significantly to the crucial ecosystem functions and services such as organic matter decomposition and nutrient cycling. The contribution of each group of soil organisms may vary depending primarily on their feeding behavior. The magnitude of the ecosystem services by the biota may also depend on the interactions amongst the soil biota groups and their surrounding environment, for instance, biochemical characteristics of the externally added organic material. However, only a few studies considered these interactions concurrently. Here, we investigated the effects of fauna-microbe-plant interactions on organic matter decomposition and nutrient cycling by applying different organic materials spanning a range of C:N ratios and presumed N availability. Nematodes were selected as model fauna because they are the most abundant soil metazoans that have a diversified feeding strategy and interact very intimately with microbes, other fauna, and plants. A series of incubation experiments were conducted in bare and planted microcosms under controlled conditions using fresh soil collected from an agricultural field and defaunated by gamma irradiation. In the first experiment without plants, the defaunated soil cores were either left unamended (UNA) or received lignin-rich low N compost (COI), N-rich compost (COV), fresh manure (MAN) or chopped clover (CLO). The entire free-living soil nematode community was extracted from unirradiated fresh soil and reinoculated into half of the soil cores that had been defaunated by gamma irradiation. Two treatments: with (+Nem) and without (-Nem) nematodes were compared for soil nitrogen and phosphorus availability, plant uptake, and PLFA signatures over time during a 105-days incubation. The same experimental setup was used to investigate further the CLO amendment in the presence of plants (rye grass was used as a model plant). Nematodes were extracted and assigned to feeding groups

  12. Effect of organic amendment and cultural practice on large patch occurrence and soil microbial community

    USDA-ARS?s Scientific Manuscript database

    Organic amendments may suppress soilborne pathogens by stimulating soil microbes. However, little information is available about the effects of organic amendments and cultural practices on suppressing large patch caused by Rhizoctonia solani Kühn on zoysiagrass (Zoysia japonica Steud.) associated wi...

  13. SPECTROSCOPIC SPECIATION AND QUANTIFICATION OF LEAD IN PHOSPHATE AMENDED SOILS

    EPA Science Inventory

    The immobilization of Pb in contaminated soils as pyromorphite [Pb5(PO4)3CI, OH, F] through the addition of various phosphate amendments has gained much attention in the remediation community. However, it is difficult to fully determine the specia...

  14. Speciation and phytoavailability of lead and antimony in a small arms range soil amended with mussel shell, cow bone and biochar: EXAFS spectroscopy and chemical extractions.

    PubMed

    Ahmad, Mahtab; Lee, Sang Soo; Lim, Jung Eun; Lee, Sung-Eun; Cho, Ju Sik; Moon, Deok Hyun; Hashimoto, Yohey; Ok, Yong Sik

    2014-01-01

    Mussel shell (MS), cow bone (CB) and biochar (BC) were selected to immobilize metals in an army firing range soil. Amendments were applied at 5% (wt) and their efficacies were determined after 175 d. For metal phytoavailability test, maize (Zea mays L.) plants were cultivated for 3weeks. Results showed that all amendments decreased the exchangeable Pb by up to 99% in planted/unplanted soils. Contrarily, exchangeable Sb were increased in the MS- and CB-amended soils. The rise in soil pH (~1 unit) by the amendments affected Pb and Sb mobility in soils. Bioavailability of Pb to maize was reduced by up to 71% in the amended soils. The Sb uptake to maize was decreased by up to 53.44% in the BC-amended soil. Sequential chemical extractions showed the transformation of easily available Pb to stable residual form with the amendment treatments. Scanning electron microscopic elemental dot mapping revealed the Pb association with Al and Si in the MS-amended soil and that with P in the CB- and BC-amended soils. Additionally, the extended X-ray absorption fine structure spectroscopic analysis indicated the transformation of organic bound Pb in unamended control soil to relatively more stable Pb-hydroxide (Ksp=10(-17.1)), chloropyromorphite (Ksp=10(-84.4)) and Pb-phosphate (Ksp=10(-23.8)) in soils amended with MS, CB and BC, respectively. Application of BC was the best in decreasing the phytoavailability of Pb and Sb in the studied army firing range soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Improvement of soil characteristics and growth of Dorycnium pentaphyllum by amendment with agrowastes and inoculation with AM fungi and/or the yeast Yarowia lipolytica.

    PubMed

    Medina, A; Vassileva, M; Caravaca, F; Roldán, A; Azcón, R

    2004-08-01

    The effectiveness of two microbiologically treated agrowastes [dry olive cake (DOC) and/or sugar beet (SB)] on plant growth, soil enzymatic activities and other soil characteristics was determined in a natural soil from a desertified area. Dorycnium pentaphyllum, a legume plant adapted to stress situations, was the test plant to evaluate the effect of inoculation of native arbuscular mycorrhizal (AM) fungi and/or Yarowia lipolytica (a dry soil adapted yeast) on amended and non-amended soils. Plant growth and nutrition, symbiotic developments and soil enzymatic activities were limited in non-amended soil where microbial inoculations did not improve plant development. The lack of nodules formation and AM colonization can explain the limited plant growth in this natural soil. The effectiveness and performance of inocula applied was only evident in amended soils. AM colonization and spores number in natural soil were increased by amendments and the inoculation with Y. lipolytica promoted this value. The effect of the inoculations on plant N-acquisition was only important in AM-inoculated plants growing in SB medium. Enzymatic activities as urease and protease activities were particularly increased in DOC amended soil meanwhile dehydrogenase activity was greatest in treatments inoculated with Y. lipolytica in SB added soil. The biological activities in rhizosphere of agrowaste amended soil, used as indices of changes in soil properties and fertility, were affected not only by the nature of amendments but also by the inoculant applied. All these results show that the lignocellulosic agrowastes treated with a selected microorganism and its further interaction with beneficial microbial groups (native AM fungi and/or Y. lipolytica) is a useful tool to modify soil physico-chemical, biological and fertility properties that enhance the plant performance probably by making nutrients more available to plants.

  16. Effect of heavy metals and organic matter on root exudates (low molecular weight organic acids) of herbaceous species: An assessment in sand and soil conditions under different levels of contamination.

    PubMed

    Montiel-Rozas, M M; Madejón, E; Madejón, P

    2016-09-01

    Bioavailability of heavy metals can be modified by different root exudates. Among them, low molecular weight organic acids (LMWOAs) play an important role in this process. Three plant species (Poa annua, Medicago polymorpha and Malva sylvestris), potentially used for phytoremediation, have been assessed for both metal uptake and LMWOAs excretion in contaminated environments with different concentrations of Cd, Cu and Zn. The experiments have been carried out in washed sand and in three contaminated soils where two organic amendments were added (biosolid compost and alperujo compost). The most abundant LMWOAs excreted by all studied plants were oxalic and malic acids, although citric and fumaric acids were also detected. The general tendency was that plants responded to an increase of heavy metal stress releasing higher amounts of LMWOAs. This is an efficient exclusion mechanism reducing the metal uptake and allowing the plant growth at high levels of contamination. In the experiment using wash sand as substrate, the organic acids composition and quantity depended mainly on plant species and metal contamination. M. polymorpha was the species that released the highest concentrations of LMWOAs, both in sand and in soils with no amendment addition, whereas a decrease of these acids was observed with the addition of amendments. Our results established a clear effect of organic matter on the composition and total amount of LMWOAs released. The increase of organic matter and nutrients, through amendments, improved the soil quality reducing phytotoxicity. As a result, organic acids exudates decreased and were solely composed of oxalic acid (except for M. polymorpha). The release of LMWOAs has proved to be an important mechanism against heavy metal stress, unique to each species and modifiable by means of organic amendment addition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Toxicological responses of red-backed salamander (Plethodon cinereus) exposed to aged and amended soils containing lead.

    PubMed

    Bazar, Matthew A; Quinn, Michael J; Mozzachio, Kristie; Bleiler, John A; Archer, Christine R; Phillips, Carlton T; Johnson, Mark S

    2010-05-01

    The use of lead in military and civilian small arms projectiles is widely acknowledged to have resulted in high soil lead concentrations at many small arms ranges. These ranges are often adjacent to wildlife habitat or have become habitat when no longer used. To assess the potential toxicity of lead to terrestrial amphibians in contaminated areas, we exposed 100 red-backed salamanders (Plethodon cinereus) to either a control soil or one of four soil treatments amended with lead acetate for 28 days. Analytical mean soil concentrations were 14 (control), 553, 1700, 4700, and 9167 mg Pb/kg soil dry weight. An additional 60 salamanders were also exposed for 28 days to one of six field-collected soil samples from a small arms range and a skeet range. The field soil concentrations ranged from 11 (background) to 16,967 mg Pb/kg soil dry weight. Food consisted of uncontaminated flightless Drosophila melanogaster. Salamander survival was reduced in amended soil treatments of 4700 and 9167 mg/kg by 15% and 80%, respectively. Inappetence was observed at 4700 and 9167 mg/kg and growth decreased in the 9167 mg/kg treatment. Total white blood cells decreased 32% at 4700 mg/kg compared to controls and were 22% lower in the 9167 mg/kg treatment. In contrast, survival was 100% for all field-collected soils with no hematological effects. At 16,967 mg/kg there was evidence of soil avoidance and decreased growth. These data suggest marked differences in toxicity and bioavailability of the lead-amended soil in contrast to the field-collected soil containing lead.

  18. Biochar Amendment to the Soil Surface Reduces Fumigant Emissions and Enhances Soil Microorganism Recovery.

    PubMed

    Shen, Guoqing; Ashworth, Daniel J; Gan, Jay; Yates, Scott R

    2016-02-02

    During soil fumigation, it is ideal to mitigate soil fumigant emissions, ensure pest control efficacy, and speed up the recovery of the soil microorganism population established postapplication. However, no current fumigant emission reduction strategy can meet all these requirements. In the present study, replicated soil columns were used to study the effect of biochar derived from rice husk (BR) and green waste (BG) applied to the soil surface on 1,3-dichloropropene (1,3-D) and chloropicrin (CP) emissions and soil gas distribution, and on microorganism population re-establishment. Relative to fumigated bare soil (no emission reduction strategy), high-density polyethylene (HDPE), and ammonium thiosulfate (ATS) treatments, BR gave dramatic emission reductions for both fumigants with no obvious emission peak, whereas BG was very effective only for 1,3-D. With BR application, the concentration of fumigant in the soil gas was higher than in the bare soil and ATS treatment. After the soil column experiment, mixing the BR with the fumigated soil resulted in higher soil respiration rates than were observed for HDPE and ATS treatments. Therefore, biochar amendment to the soil surface may be an effective strategy for fumigant emission reduction and the recovery of soil microorganism populations established postapplication.

  19. Lead and Arsenic Uptake by Leafy Vegetables Grown on Contaminated Soils: Effects of Mineral and Organic Amendments

    PubMed Central

    McBride, Murray B.; Simon, Tobi; Tam, Geoffrey; Wharton, Sarah

    2015-01-01

    To assess strategies for mitigating Pb and As transfer into leafy vegetables from contaminated garden soils, we conducted greenhouse experiments using two field-contaminated soils amended with materials expected to reduce metal phytoavailability. Lettuce and mustard greens grown on these soils were analysed by ICP-MS, showing that some Pb and As transfer into the vegetables occurred from both soils tested, but plant Pb concentrations were highly variable among treatment replicates. Soil-to-plant transfer was more efficient for As than for Pb. Contamination of the leaves by soil particles probably accounted for most of the vegetable Pb, since plant Pb concentrations were correlated to plant tissue concentrations of the immobile soil elements Al and Fe. This correlation was not observed for vegetable As concentrations, evidence that most of the soil-to-plant transfer for this toxic metal occurred by root uptake and translocation into the above-ground tissues. A follow-up greenhouse experiment with lettuce on one of the two contaminated soils revealed a lower and less variable foliar Pb concentration than observed in the first experiment, with evidence of less soil particle contamination of the crop. This reduced transfer of Pb to the crop appeared to be a physical effect attributable to the greater biomass causing reduced overall exposure of the above-ground tissues to the soil surface. Attempts to reduce soil Pb and As solubility and plant uptake by amendment at practical rates with stabilizing materials including composts, peat, Ca phosphate, gypsum and Fe oxide, were generally unsuccessful. Only Fe oxide reduced soluble As in the soil, but this effect did not persist. Phosphate amendment rapidly increased soil As solubility but had no measurable effect on either soil Pb solubility or concentrations of Pb or As in the leafy vegetables. The ineffectiveness of these amendments in reducing Pb transfer into leafy vegetables is attributed in this study to the low

  20. Mobility of selected trace elements in Mediterranean red soil amended with phosphogypsum: experimental study.

    PubMed

    Kassir, Lina Nafeh; Darwish, Talal; Shaban, Amin; Ouaini, Naim

    2012-07-01

    Soil amendment by phosphogypsum (PG) application becomes of increasing importance in agriculture. This may lead, however, to soil, plant, and groundwater contamination with trace elements (TEs) inherently present in PG. Monitoring of selected TEs (Pb, Zn, Cu, and Cd) distribution and mobility in a Mediterranean red soil profile has been performed in soil parcels applied with PG over a 16-month period. Concentrations were measured in soil and plant samples collected from various depth intervals at different points in time. TEs sequential extraction was performed on soil and PG samples. Results showed soil profile enrichment peaked 5 months after PG application for Cd, and 12 months for Pb, Zn, and Cu. Rainwater, pH, total organic carbon, and cationic exchange capacity were the main controlling factors in TEs accumulation in soils. Cd was transferred to a soil depth of about 20 cm. Zn exhibited mobility towards deeper layers. Pb and Cu were accumulated in around 20-55-cm-deep layers. PG increased the solubility of the studied TEs; PG-applied soils contained TEs bound to exchangeable and acid-soluble fractions in higher percentages than reference soil. Pb, Zn, and Cu were sorbed into mineral soil phases, while Cd was mainly found in the exchangeable (bio-available) form. The order of TEs decreasing mobility was Zn > Cd > Pb > Cu. Roots and leaves of existed plants, Cichorium intybus L., accumulated high concentrations of Cd (1-2.4 mg/kg), exceeding recommended tolerable levels, and thus signifying potential health threats through contaminated crops. It was therefore recommended that PG should be applied in carefully established, monitored, and controlled quantities to agricultural soils.

  1. Properties of biochar-amended soils and their sorption of imidacloprid, isoproturon, and atrazine.

    PubMed

    Jin, Jie; Kang, Mingjie; Sun, Ke; Pan, Zezhen; Wu, Fengchang; Xing, Baoshan

    2016-04-15

    Biochars produced from rice straw, wheat straw and swine manure at 300, 450 and 600°C were added to soil at 1, 5, 10, or 20% levels to determine whether they would predictably reduce the pore water concentration of imidacloprid, isoproturon, and atrazine. The sorption capacity of the mixtures increased with increasing biochar amounts. The enhanced sorption capacity could be attributed to the increased organic carbon (OC) content and surface area (SA) as well as the decreased hydrophobicity. Biochar dominated the overall sorption when its content was above 5%. The OC contents of the mixtures with 10% and 20% biochar were generally lower than the predicted values. This implies possible interaction between soil components and biochar and/or the effect of biochar oxidation. For soils amended with biochars produced at 300°C, the N2 SA (N2-SA) values were underestimated. The predicted CO2 SA (CO2-SA) values of the mixtures at the biochar content of 10% and 20% were generally higher than the experimental values. Sorption of imidacloprid to the soils amended with biochar at 10% and 20% levels, excluding the soils amended with rice (SR300) and wheat (SW300) straw-derived biochar produced at 300°C, was lower than the predicted value. For SR300 and SW300, the intrinsic sorption capacity of biochar was enhanced by 1.3-5.6 times, depending on the biochar, solute concentration, and biochar dose. This study indicates that biochars would be helpful to stabilize the soil contaminated with imidacloprid, isoproturon, and atrazine, but the sorption capacity of the mixtures could exceed or fall short of predicted values without assuming a cross-effect between soil and biochar. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Community level physiological profiles (CLPP), characterization and microbial activity of soil amended with dairy sewage sludge.

    PubMed

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy

    2012-01-01

    The aim of the present work was to assess the influence of organic amendment applications compared to mineral fertilization on soil microbial activity and functional diversity. The field experiment was set up on a soil classified as an Eutric Cambisol developed from loess (South-East Poland). Two doses of both dairy sewage sludge (20 Mg·ha(-1) and 26 Mg·ha(-1)) and of mineral fertilizers containing the same amount of nutrients were applied. The same soil without any amendment was used as a control. The soil under undisturbed native vegetation was also included in the study as a representative background sample. The functional diversity (catabolic potential) was assessed using such indices as Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H). These indices were calculated, following the community level physiological profiling (CLPP) using Biolog Eco Plates. Soil dehydrogenase and respiratory activity were also evaluated. The indices were sensitive enough to reveal changes in community level physiological profiles due to treatment effects. It was shown that dairy sewage amended soil was characterized by greater AWCD, R, H and dehydrogenase and respiratory activity as compared to control or mineral fertilized soil. Analysis of variance (ANOVA) and principal component analysis (PCA) were used to depict the differences of the soil bacterial functional diversity between the treatments.

  3. Community Level Physiological Profiles (CLPP), Characterization and Microbial Activity of Soil Amended with Dairy Sewage Sludge

    PubMed Central

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy

    2012-01-01

    The aim of the present work was to assess the influence of organic amendment applications compared to mineral fertilization on soil microbial activity and functional diversity. The field experiment was set up on a soil classified as an Eutric Cambisol developed from loess (South-East Poland). Two doses of both dairy sewage sludge (20 Mg·ha−1 and 26 Mg·ha−1) and of mineral fertilizers containing the same amount of nutrients were applied. The same soil without any amendment was used as a control. The soil under undisturbed native vegetation was also included in the study as a representative background sample. The functional diversity (catabolic potential) was assessed using such indices as Average Well Color Development (AWCD), Richness (R) and Shannon–Weaver index (H). These indices were calculated, following the community level physiological profiling (CLPP) using Biolog Eco Plates. Soil dehydrogenase and respiratory activity were also evaluated. The indices were sensitive enough to reveal changes in community level physiological profiles due to treatment effects. It was shown that dairy sewage amended soil was characterized by greater AWCD, R, H and dehydrogenase and respiratory activity as compared to control or mineral fertilized soil. Analysis of variance (ANOVA) and principal component analysis (PCA) were used to depict the differences of the soil bacterial functional diversity between the treatments. PMID:22737006

  4. The application of soil amendments benefits to the reduction of phosphorus depletion and the growth of cabbage and corn.

    PubMed

    Liu, Wei; Ji, Hongli; Kerr, Philip; Wu, Yonghong; Fang, Yanming

    2015-11-01

    The loss of phosphorus from agricultural intensive areas can cause ecological problems such as eutrophication in downstream surface waters. Therefore, the purpose of this study is to control the phosphorus loss using environmentally benign soil amendments, viz, ferrous sulfate (FES), aluminum sulfate (ALS), and polyacrylamide (PAM). The phosphorus concentration changes in soil and leaching solution, the morphological index of plant (including stem and root), and root activity and quality (represented by chlorophyll and soluble sugar) at different growth stages of cabbage (Brassica oleracea L. var. capitata L.) were monitored in a pilot experiment. Phosphorus contents in soil and runoff were also investigated in field experiments cultivated with corn (Zea mays L.). The results show that the application of these amendments improved the phosphorus uptake by cabbage and corn, resulting in the enhanced morphologies of root and stem as well as the root activity at the early and middle stages of cabbage growth. The soil total phosphorus and available phosphorus in soils treated with FES, ALS, and PAM declined, resulting in lower concentrations of phosphorus in the leachate and the soil runoff. During the use of the soil amendments, the cabbage quality measures, determined as chlorophyll and soluble sugar in leaves, were not significantly different from those in the control. It is suggested that the application of these soil amendments is safe for cabbage production under single season cropping conditions, and the use of these three amendments is a promising measure to reduce phosphorus loss in intensive agricultural areas.

  5. EVALUATION OF LEAD AVAILABILITY IN AMENDED SOILS MONITORED OVER A LONG-TERM TIME PERIOD

    EPA Science Inventory

    Two different soil amendment processes were evaluated for reducing lead availability from a contaminated soil at a demonstration study site, to reduce potential public health and environmental concerns. A limited variety of in vitro laboratory availability tests (relativ...

  6. Leaching of nitrogen and base cations from calcareous soil amended with organic residues.

    PubMed

    Zarabi, Mahboubeh; Jalali, Mohsen

    2012-01-01

    The potential for groundwater and surface water pollution by nutrients in organic residues, primarily nitrogen (N) and base cations (K+, Na+, Ca2+, Mg2+), is a consideration when applying such residues to land. In this study, we used a laboratory column leaching procedure to examine the leaching of N, K+, Na+, Ca2+ and Mg2+ in soils treated with two types of raw organic residues (poultry manure and potato residues) and one municipal waste compost, which are currently recycled on agricultural land in Iran. Each organic residue was thoroughly mixed with two different soils (sandy loam and clay) at the rate of 3%. Soil columns were leached at 4-d intervals for 92 d with distilled water, and effluents were analysed for pH, EC, nitrate (NO3(-)-N), ammonium (NH4(+)-N) K+, Na+, Ca2+ and Mg2+. The results indicated that the amounts of NO3(-)-N and NH4(+)-N leached from the poultry manure and potato residues could represent very important economic losses of N and pose an environmental threat under field conditions. The sandy loam soil amended with poultry manure lost the highest amount of NO3(-)-N (206.4 kg ha(-1)), and clay soil amended with poultry manure lost the highest amounts of NH4(+)-N (454.3 kg ha(-1)). The results showed that a treatment incorporating 3% of municipal waste compost could be used without negative effects to groundwater N concentration in clay soil. Significant amounts of K+, Na+, Ca2+, and Mg2+ were leached owing to the application of poultry manure, potato and municipal waste compost to soils. There was a positive relationship between K+, Na+, Ca2+, and Mg2+ with NO3(-)-N and NH4(+)-N leached in soils. Analysis of variance detected significant effects of amendment, soil type and time on the leaching NO3(-)-N, NH4(+)-N, K+, Na+, Ca2+ and Mg2+.

  7. Evaluation and decontamination of crude oil-polluted soils using Centrosema pubescen Benth and amendment-support options.

    PubMed

    Nwaichi, Eucharia O; Osuji, Leo C; Onyeike, Eugene N

    2011-04-01

    Growth performance and phytoremediation of soil of the Niger Delta Region of Nigeria artificially-contaminated with crude oil (up to 100 mL/2 kg soil) using centrosema pubescen Benth was investigated for 12 weeks. The soil samples in which the plants were established were either un-amended, or amended with NPK, or UREA or chicken manure. The extents of removal of PAHs and BTEX were measured as well as the rates of growth of the plants. Gas Chromatographic analysis confirmed the degradation of carcinogenic hydrocarbons like BTEXs and PAHs with this technique. At the highest dose of crude, the contaminant concentrations were 43 mg/kg PAHs, 10 mg/kg BTEX, and 5,613 mg/kg O&G. The greatest percent removal of BTEX was observed at the highest contaminant dose, and with the manure amendment. Similar trends were observed with PAHs and although they were less marked, the trends with PAHs may have been more highly statistically significant. There was no measurable plant uptake of contaminants. Inhibition of plant growth (measured as leaf area, shoot length and production of dry weight) was proportional to the dose of crude oil, but the manure amendment was very effective at reducing the growth inhibition. Interestingly, manure amendment reduced the phytotoxicity significantly in this study.

  8. Stabilization of lead and copper by biochar amendments in arms range soils: Influence of biochar characteristics, soil property, and equilibrium conditions

    USDA-ARS?s Scientific Manuscript database

    Soil amendment of char products (biochar) from thermochemical processing (slow/fast pyrolysis and gasification) of biomass for biofuel production has received considerable interests for contaminant sorption, soil fertilization, and carbon sequestration. Of potential sites for biochar application, h...

  9. Lime and compost promote plant re-colonization of metal-polluted, acidic soils.

    PubMed

    Ulriksen, Christopher; Ginocchio, Rosanna; Mench, Michel; Neaman, Alexander

    2012-09-01

    The revegetation of soils affected by historic depositions of an industrial complex in Central Chile was studied. The plant re-colonization from the existing soil seed bank and changes in the physico-chemical properties of the soil were evaluated in field plots amended with lime and/or compost. We found that the application of lime and/or compost decreased the Cu2+ ion activity in the soil solution and the exchangeable Cu in the soil, showing an effective Cu immobilization in the topsoil. Whereas lime application had no effect on plant productivity in comparison with the unamended control, the application of compost and lime+compost increased the plant cover and aboveground biomass due to the higher nutrient availability and water-holding capacity of the compost-amended soils. Although the Cu2+ activity and the exchangeable Cu were markedly lower in the amended soils than in the unamended control, the shoot Cu concentrations of Lolium spp. and Eschscholzia californica did not differ between the treatments.

  10. Growth and physiological response of lemongrass (Cymbopogon citratus (D.C.) Stapf.) under different levels of fly ash-amended soil.

    PubMed

    Panda, Debabrata; Panda, Dibyajyoti; Padhan, Bandana; Biswas, Meghali

    2018-05-12

    Revegetation with metal tolerant plants for management of fly ash deposits is an important environmental perspective nowadays. Growth performance, photosynthesis, and antioxidant defense of lemongrass (Cymbopogon citratus (D.C.) Stapf.) were evaluated under various combination of fly ash amended with garden soil in order to assess its fly ash tolerance potential. Under low level of fly ash (25%) amended soil, the plant growth parameters such as shoot, root, and total plant biomass as well as metal tolerance index were increased compared to the control plants grown on garden soil, followed by decline under higher concentration of fly ash (50%, 75% and 100%). In addition, leaf photosynthetic rate, stomatal conductance, and photosystem (PS) II activity were not significantly changed under low level of fly ash (25%) amended soil compared to the garden soil but these parameters were significantly decreased further with increase of fly ash concentrations. Furthermore, increase of activities of some antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, and guaiacol peroxidase over control were noticed in lemongrass under all fly ash treatments. Taken together, the study suggests that lemongrass can be used for phytoremediation of fly ash at 25% amended soil.

  11. Remediation of an acidic mine spoil: Miscanthus biochar and lime amendment affects metal availability, plant growth and soil enzymatic activity

    USDA-ARS?s Scientific Manuscript database

    Biochar is proposed as an amendment for mine spoil remediation; however, its effectiveness at achieving this goal remains unclear. Miscanthus (Miscanthus giganteus) biochar was tested for potentially improving acidic mine spoil (pH < 3; Formosa mine near Riddle, Oregon) health conditions by sequeste...

  12. Modeling fungicides mobility in undisturbed vineyard soil cores unamended and amended with spent mushroom substrates.

    PubMed

    Marín-Benito, Jesús María; Rodríguez-Cruz, María Sonia; Sánchez-Martín, María Jesús; Mamy, Laure

    2015-09-01

    The performance of the pesticide fate model PRZM to predict the fate of two fungicides, penconazole and metalaxyl, and the major metabolite of metalaxyl (CGA-62826), in amended and unamended vineyard soils was tested from undisturbed soils columns experiments. Three different treatments were tested in two soils: control soil (unamended), and soil amended with fresh or composted spent mushroom substrates, which correspond to common agricultural practices in Spain. Leaching experiments were performed under non-saturated flow conditions. The model was parameterized with laboratory and literature data, and using pedotransfer functions. It was first calibrated for water flow against chloride breakthrough curves. The key parameter was the hydrodynamic dispersion coefficient (DISP). No leaching of penconazole, the most hydrophobic fungicide, was observed. It remained in the top 0-8 cm of the column. In any case, simulations were highly correlated to the experimental results. On the contrary, metalaxyl and its metabolite were consistently found in the leachates. A calibration step of the Kd of metalaxyl and CGA-62826 and of DISP for CGA-62826 was necessary to obtain good prediction of the leaching of both compounds. PRZM generally simulated acceptable metalaxyl vertical distribution in the soil profiles although results were overestimated for its metabolite. Nevertheless, PRZM can be reasonably used to assess the leaching (through breakthrough curves) and vertical distribution of fungicides in amended soils, knowing their DISP values. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Influence of olive oil mill waste amendment on fate of oxyfluorfen in Southern Spain soils

    USDA-ARS?s Scientific Manuscript database

    The influence of olive oil mill waste (OOMW) amendment on soil processes affecting the herbicide oxyfluorfen (2-chloro-4-trifluoromethylphenyl-3-ethoxy-4-nitrophenyl ether) in two soils (P2 and SJ) was assessed under laboratory conditions. The soils used were from two diverse locations in Guadalqui...

  14. Phosphorus Amendment Efficacy for In Situ Remediation of Soil Lead Depends on the Bioaccessible Method

    EPA Science Inventory

    A validated method is needed to measure reductions of in vitro bioaccessible (IVBA) Pb in urban soil remediated with amendments. This study evaluated the effect of in vitro extraction solution pH and glycine buffer on bioaccesible Pb in P-treated soils. Two Pb-contaminated soils...

  15. Greenhouse gas emission and groundwater pollution potentials of soils amended with different swine biochars

    USDA-ARS?s Scientific Manuscript database

    The objective of this research was to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with various biochars using different biomass feedstocks and thermal processing conditions. Triplicate sets of small pots were designed; control soil consisting of Histi...

  16. A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil*

    PubMed Central

    Nourbakhsh, Farshid; Sheikh-Hosseini, Ahmad R.

    2006-01-01

    The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO2-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO2-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO2 evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (C 0) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation. PMID:16972320

  17. The Role of Soil Amendment on Tropical Post Tin Mining Area in Bangka Island Indonesia for Dignified and Sustainable Environment and Life

    NASA Astrophysics Data System (ADS)

    Agus, C.; Wulandari, D.; Primananda, E.; Hendryan, A.; Harianja, V.

    2017-08-01

    Openly tropical tin mining in Bangka Island Indonesia expose heavy metal that had been buried became a part of our environment and life. This has become a major cause of land degradation and severe local-global environmental damages. This study aims to accelerate reconsolidation of degraded ecosystems on the former tin mine land, to increase land productivity and dignified environment through appropriate rehabilitation technology on marginal land that is inexpensive, environmentally friendly and sustainable. This study is a part of a roadmap research activities on the rehabilitation of degraded land in tropical ecosystem, that consist of (a) characterization of degraded tin mining lands through the determination of chemistry, physics, biology and mineral soil properties, (b) introducing multi-function pioneers plant for acceleration of peak pioneer plant in the reestablishment of degraded tin mining ecosystem (c) management of natural soil amendment (volcanic ash, organic waste materials and legume cover crop as a material for soil amelioration to increase land productivity, (d) role of biotechnology through the application of local bio-fertilizer (mycorrhizae, phosphate soluble bacteria, rhizobium). Soil from post tropical tin mining acid soil (pH 4.97) that dominated by sand particles (88%) with very low cation exchange capacity, very low nutrient contents (available and total-N, P, K, Ca, Mg) and high toxicity of Zn, Cu, B, Cd and Ti, but still have low toxicity of Al, Fe, Mn, Mo, Pb, As. Soil amendment of biogas and volcanic ash could improve soil quality by increasing of better pH, high available-P and cation exchange capacity and maintained their low toxicity. The growth (high, diameter, biomass, top-root ratio) of exotic pioneer plant of Kemiri sunan (Reutealis trisperma) increased in the better soil quality that caused by application of proper soil amendment. The grand concept and appropriate technology for rehabilitation of degraded tin-mining land

  18. Raw or incubated olive-mill wastes and its biotransformed products as agricultural soil amendments-effect on sorption-desorption of triazine herbicides.

    PubMed

    Delgado-Moreno, Laura; Almendros, Gonzalo; Peña, Aránzazu

    2007-02-07

    Raw olive-mill waste and soil amendments obtained from their traditional composting or vermicomposting were added, at rates equivalent to 200 Mg ha-1, to a calcareous silty clay loam soil in a laboratory test, in order to improve its fertility and physicochemical characteristics. In particular, the effects on the sorption-desorption processes of four triazine herbicides have been examined. We found that comparatively hydrophobic herbicides terbuthylazine and prometryn increased their retention on amended soil whereas the more polar herbicides simazine and cyanazine were less affected. Soil application of olive cake, without transformation, resulted in the highest herbicide retention. Its relatively high content in aliphatic fractions and lipids could explain the increased herbicide retention through hydrophobic bonding and herbicide diffusion favored by poorly condensed macromolecular structures. On the other hand, the condensed aromatic structure of the compost and vermicompost from olive cake could hinder diffusion processes, resulting in lower herbicide sorption. In fact, the progressive humification in soil of olive-mill solid waste led to a decrease of sorption capacity, which suggested important changes in organic matter quality and interactions during the mineralization process. When soil amended with vermicompost was incubated for different periods of time, the enhanced herbicide sorption capacity persisted for 2 months. Pesticide desorption was reduced by the addition of fresh amendments but was enhanced during the transformation process of amendments in soil. Our results indicate the potential of soil amendments based on olive-mill wastes in the controlled, selective release of triazine herbicides, which varies depending on the maturity achieved by their biological transformation.

  19. Evaluation of carbon and nitrogen pools in different soil types amended with different organic inputs by thermogravimetric/calorimetric analysis

    NASA Astrophysics Data System (ADS)

    Yanardaǧ, Ibrahim H.; Zornoza, Raúl; Büyükkiliç-Yanardaǧ, Asuman; Acosta, Jose A.; Faz, Ángel; Mermut, Ahmet R.

    2017-04-01

    The objective of this study was to assess the short-term changes in soil organic C (SOC) and N pools after incubation of three different soil types (Regosol, Luvisol and Kastanozem) treated with three amendments differing in organic matter stability (raw pig slurry (PS), manure, and biochar (BC), and to establish relationships between different chemical, spectral and thermal/calorimetric data to assess if thermal/calorimetric analysis could replace conventional analyses to monitor changes in SOC and N poos. Thermogravimetry-Differential Scanning Calorimetry (TG-DSC) analysis showed that amendments had little effect on volatile SOC and inorganic matter, compared to unamended samples in all soils. All amendments significantly increased the labile SOC in Regosol. Manure and BC increased recalcitrant SOC in Regosol and Luvisol. BC significantly increased recalcitrant SOC in all soils. Refractory SOC slightly increased with amendments in the Luvisol compared to the control. These results support the findings obtained with chemical analyses. Selected evolved ions (m/z 30 and 44) detected by quadrupole mass spectrometry (QMS) confirmed findings from TG-DSC. Emissions of C and N containing gases from the Regosol significantly increased with the amendments because this soil contains low SOC content, and the application of these amendments provided additional C. An increase in the CO2 containing gas species (m/z 44) from volatile SOC was observed with PS application only in the Regosol. Carbon dioxide increments (m/z 44) from recalcitrant (380-475°C) and refractory (475-550/600°C) SOC pools were observed with all amendments in all soils especially with BC application. The evolved ions at m/z 44 were higher in the initial soil samples from Kastanozem than after incubation, suggesting a loss of organic compounds, mainly volatile and labile upon incubation. NO peaks (m/z 30) showed similar trends to the C containing gas species in all soils. We carried out linear regressions

  20. Influence of amendment type on persistence of Salmonella Newport in soil

    USDA-ARS?s Scientific Manuscript database

    Introduction: Salmonella Newport is a foodborne pathogen isolated from several environmental reservoirs on the DelMarVa Peninsula and has been associated with several produce-related outbreaks.Little is known about interactions between S. Newport and soil amendments used as fertilizers. Purpose: Th...

  1. Dissolved organic matter dynamic and resident microbiota evolution in soil amended with fresh and composted olive mill wastes

    NASA Astrophysics Data System (ADS)

    Gigliotti, Giovanni; Massaccesi, Luisa; Federici, Ermanno; Fidati, Laura; Nasini, Luigi; Proietti, Primo

    2013-04-01

    The disposal of olive mill wastes represents a problem of environmental relevance particularly in the Mediterranean countries where olive oil is mostly produced. Among the several valorisation and recycling methods proposed, interesting for its operational simplicity and convenience is land spreading, either directly or after composting. However, the agriculture use of the water-saturated husk produced by the new two-phase oil extraction systems may be hampered by its consistency and its high content of phenolic compounds, which may finally lead to phytotoxicity. Humid husk may indeed modify the dynamic of soil organic matter (SOM) and the structure and function of microbial communities. On the other hand, organic amendments are known to positively affect SOM fractions, particularly by increasing the concentration and quality of dissolved organic matter (DOM), which may eventually lead to an increase in microbial activity. The aim of this work was to investigate, during a 90-day field trial, the modifications in soil DOM composition and the effects on the soil microbiota induced by a humid husk, obtained from a new generation two-phase oil extraction plant, spread in an olive orchard either as a fresh amendment or after a composting process. With respect to the control, the soil amended with either fresh or composted husk showed an increase in water extractable organic carbon (WEOC). Interestingly, while during the first 30 days the soil amended with the composted husk showed a WEOC content higher than the one amended with the fresh husk, after that time only in the latter the WEOC remained significantly higher than in the control. The total content of phenolic compounds showed a similar trend, with the only difference that their concentration in the soil amended with both treatments remained higher than the control for the entire trial. Similarly, both treatments induced an increase in soil reducing sugars, with an higher effect observed in the soil amended with

  2. The influence of redox chemistry and pH on chemically active forms of arsenic in sewage sludge-amended soil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbonell-Barrachina, A.; Jugsujinda, A.; DeLaune, R.D.

    1999-07-01

    Chemical fractionation procedures were used to quantify the effect of the sediment redox and pH conditions on the adsorption and solubility of arsenic (As) in municipal sewage sludge and sewage sludge-amended soil. Sludge and sludge-amended soil were incubated in microcosms in which Eh-pH conditions were controlled. Samples were sequentially extracted to determine As in various chemical forms (water soluble, exchangeable, bound to carbonates, bound to iron (Fe) and manganese (Mn) oxides, bound to insoluble organics and sulfides) and the chemically inactive fraction (mineral residues). In both sewage sludge and sludge-amended soil, As chemistry was governed by large molecular humic mattermore » and sulfides and Fe and Mn-oxides. Solubility of As remained low and constant under both aerobic and anaerobic conditions in sludge-amended soil. After dissolution of Fe and Mn-oxides, As{sup 5+} was released into sludge solution, reduced to As{sup 3+} and likely precipitated as sulfide. Therefore, an organic amendment rich in sulfur compounds, such as sewage sludge, would drastically reduce the potential risks derived from As pollution under highly anoxic conditions by precipitation of this toxic metalloid as insoluble and immobile sulfides.« less

  3. Effect of Polonite used for phosphorus removal from wastewater on soil properties and fertility of a mountain meadow.

    PubMed

    Cucarella, Victor; Mazurek, Ryszard; Zaleski, Tomasz; Kopeć, Michał; Renman, Gunno

    2009-07-01

    Reactive filter materials used for phosphorus (P) removal from wastewater can be disposed of as soil amendments after treatment, thus recycling P and other macro- and micro-nutrients to plants. In addition, materials with a high pH and Ca content, such as Polonite, are potential soil conditioners, which can be particularly beneficial for acid soils. Polonite previously used for on-site wastewater treatment was applied as a soil amendment to a mountain meadow. The amendment significantly increased soil pH and decreased the hydrolytic acidity, thus reducing Al toxicity risks. The effects were comparable to those of liming. No difference in yield and P uptake by meadow plants was observed. The uptake of metals was lower for amended soils, especially the uptake of Mn. Using Polonite after wastewater treatment as a soil amendment is thus a viable disposal alternative that can replace liming, when necessary, being capable of recycling P and other nutrients to meadow plants.

  4. Effects of combined amendments on crop yield and cadmium uptake in two cadmium contaminated soils under rice-wheat rotation.

    PubMed

    Guo, Fuyu; Ding, Changfeng; Zhou, Zhigao; Huang, Gaoxiang; Wang, Xingxiang

    2018-02-01

    Soil cadmium (Cd) contamination in China has become a serious concern due to its high toxicity to human health through food chains. A pot experiment was conducted to investigate the effects of hydrated lime (L), hydroxyapatite (H) and organic fertilizer (F) alone or in combination to remedy a mild (DY) and a moderate (YX) Cd contaminated agricultural soil under rice-wheat rotation. Results showed that crops grain yield and Cd concentration, soil pH, CaCl 2 extractable Cd and Cd speciation were markedly affected by the amendments. In both cropping seasons, hydrated lime and hydroxyapatite significantly immobilized soil Cd, and hydroxyapatite, organic fertilizer significantly increased grain yield. Hydrated lime mainly increased soil carbonates bound Cd fractions resulted from 16.7% to 36.2% and from 16.8% to 28.3%, and hydroxyapatite increased Fe/Mn oxides Cd fractions from 19.3% to 33.4% and from 31.4% to 42.1% in the DY and YX soils, respectively; while organic fertilizer slightly increased soil exchangeable and organic matter bound Cd fractions. Besides, combined amendments contain alkaline materials and organic materials have the potential to decrease grain Cd and increase grain yield simultaneously. Therefore, in view of the effects of amendments on grain yield and Cd concentration, the cost as well as the potential benefits expected, combined amendments like hydrated lime + organic fertilizer, hydrated lime + hydroxyapatite + organic fertilizer are recommended in practical application. Mechanisms of Cd immobilization affected by amendments are mainly attributed to the changes in soil Cd availability and crops root uptake rather than internal translocation in plants. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. [Effects of different amendments on contents of phenolic acids and specific microbes in rhizosphere of Pseudostellaria heterophylla.

    PubMed

    Wu, Lin Kun; Wu, Hong Miao; Zhu, Quan; Chen, Jun; Wang, Juan Ying; Wu, Yan Hong; Lin, Sheng; Lin, Wen Xiong

    2016-11-18

    Pseudostellaria heterophylla is a perennial herbaceous plant in the family Caryophyllaceae. The tuberous roots of P. heterophylla are highly valued in traditional Chinese medicine and have a high market demand. However, extended monoculture of P. heterophylla results in a significant decline in the biomass and quality, and escalates disease and pest problems. Therefore, it is important to understand the underlying mechanism and biocontrol methods for consecutive monoculture problems. With "Zheshen 2" as an experimental material, the changes in the contents of main nutrients in soil, phenolic acids and specific microbes under monoculture and different amendments were analyzed by using high performance liquid chromatography (HPLC) and qPCR. The results showed that consecutive monoculture of P. heterophylla led to a decrease in yield by 43.5% while the microbial fertilizer treatment and the paddy-upland rotation could relieve the consecutive monoculture problems. Available nitrogen, available phosphorus, available potassium and total potassium were significantly higher in the consecutively monocultured soils than in the newly planted soils. But consecutive monoculture resulted in soil acidification. HPLC analysis showed that conse-cutive monoculture of this plant did not lead to a consistent accumulation of soil phenolic acids. At middle stage of root expansion and at harvest stage, most of phenolic acids were even higher in the newly planted soils than in the consecutively monocultured soils. Furthermore, qPCR analysis showed that the amounts of three specific pathogens identified previously (i.e. Fusarium oxysporum, Talaromyces helicus, Kosakonia sacchari) were significantly higher in the consecutively monocultured soils than in the newly planted soils. However, the microbial fertilizer treatment and the paddy-upland rotation resulted in a significant decline in the population of these specific pathogens and improved the soil environment. In conclusion, the

  6. Nature of fly ash amendments differently influences oxidative stress alleviation in four forest tree species and metal trace element phytostabilization in aged contaminated soil: A long-term field experiment.

    PubMed

    Labidi, Sonia; Firmin, Stéphane; Verdin, Anthony; Bidar, Géraldine; Laruelle, Frédéric; Douay, Francis; Shirali, Pirouz; Fontaine, Joël; Lounès-Hadj Sahraoui, Anissa

    2017-04-01

    Aided phytostabilization using coal fly ashes (CFAs) is an interesting technique to clean-up polluted soils and valorizing industrial wastes. In this context, our work aims to study the effect of two CFAs: silico-aluminous (CFA1) and sulfo-calcic (CFA2) ones, 10 years after their addition, on the phytostabilization of a highly Cd (cadmium), Pb (lead) and Zn (zinc) contaminated agricultural soil, with four forest tree species: Robinia pseudoacacia, Alnus glutinosa, Acer pseudoplatanus and Salix alba. To assess the effect of CFAs on trees, leaf fatty acid composition, malondialdehyde (MDA), oxidized and reduced glutathione contents ratio (GSSG: GSH), 8-hydroxy-2'-deoxyguanosine (8-OHdG), Peroxidase (PO) and Superoxide dismutase (SOD) activities were examined. Our results showed that CFA amendments decreased the CaCl 2- extractable fraction of Cd and Zn from the soil. However, no significant effect was observed on metal trace element (MTE) concentrations in leaves. Fatty acid percentages were only affected by the addition of sulfo-calcic CFA. The most affected species were A. glutinosa and R. pseudoacacia in which C16:0, C18:0 and C18:2 percentages increased significantly whereas the C18:3 decreased. The addition of sulfo-calcic CFA induced the antioxidant systems response in tree leaves. An increase of SOD and POD activities in leaves of trees planted on the CFA2-amended plot was recorded. Conversely, silico-aluminous CFA generated a reduction of lipid and DNA oxidation associated with the absence or low induction of anti-oxidative processes. Our study evidenced oxidative stress alleviation in tree leaves due to CFA amendments. MTE mobility in contaminated soil and their accumulation in leaves differed with the nature of CFA amendments and the selected tree species. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Soil bacterial communities of a calcium-supplemented and a reference watershed at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA.

    PubMed

    Sridevi, Ganapathi; Minocha, Rakesh; Turlapati, Swathi A; Goldfarb, Katherine C; Brodie, Eoin L; Tisa, Louis S; Minocha, Subhash C

    2012-03-01

    Soil Ca depletion because of acidic deposition-related soil chemistry changes has led to the decline of forest productivity and carbon sequestration in the northeastern USA. In 1999, acidic watershed (WS) 1 at the Hubbard Brook Experimental Forest (HBEF), NH, USA was amended with Ca silicate to restore soil Ca pools. In 2006, soil samples were collected from the Ca-amended (WS1) and reference watershed (WS3) for comparison of bacterial community composition between the two watersheds. The sites were about 125 m apart and were known to have similar stream chemistry and tree populations before Ca amendment. Ca-amended soil had higher Ca and P, and lower Al and acidity as compared with the reference soils. Analysis of bacterial populations by PhyloChip revealed that the bacterial community structure in the Ca-amended and the reference soils was significantly different and that the differences were more pronounced in the mineral soils. Overall, the relative abundance of 300 taxa was significantly affected. Numbers of detectable taxa in families such as Acidobacteriaceae, Comamonadaceae, and Pseudomonadaceae were lower in the Ca-amended soils, while Flavobacteriaceae and Geobacteraceae were higher. The other functionally important groups, e.g. ammonia-oxidizing Nitrosomonadaceae, had lower numbers of taxa in the Ca-amended organic soil but higher in the mineral soil. Published 2011. This article is a U.S. Government work and is in the public domain in the USA.

  8. Immobilization of Pb, Cd, and Zn in a contaminated soil using eggshell and banana stem amendments: metal leachability and a sequential extraction study.

    PubMed

    Ashrafi, Mehrnaz; Mohamad, Sharifah; Yusoff, Ismail; Shahul Hamid, Fauziah

    2015-01-01

    Heavy-metal-contaminated soil is one of the major environmental pollution issues all over the world. In this study, two low-cost amendments, inorganic eggshell and organic banana stem, were applied to slightly alkaline soil for the purpose of in situ immobilization of Pb, Cd, and Zn. The artificially metal-contaminated soil was treated with 5% eggshell or 10% banana stem. To simulate the rainfall conditions, a metal leaching experiment for a period of 12 weeks was designed, and the total concentrations of the metals in the leachates were determined every 2 weeks. The results from the metal leaching analysis revealed that eggshell amendment generally reduced the concentrations of Pb, Cd, and Zn in the leachates, whereas banana stem amendment was effective only on the reduction of Cd concentration in the leachates. A sequential extraction analysis was carried out at the end of the experiment to find out the speciation of the heavy metals in the amended soils. Eggshell amendment notably decreased mobility of Pb, Cd, and Zn in the soil by transforming their readily available forms to less accessible fractions. Banana stem amendment also reduced exchangeable form of Cd and increased its residual form in the soil.

  9. Urea Amendment Decreases Microbial Diversity and Selects for Specific Nitrifying Strains in Eight Contrasting Agricultural Soils

    PubMed Central

    Staley, Christopher; Breuillin-Sessoms, Florence; Wang, Ping; Kaiser, Thomas; Venterea, Rodney T.; Sadowsky, Michael J.

    2018-01-01

    Application of nitrogen (N) fertilizers, predominantly as urea, is a major source of reactive N in the environment, with wide ranging effects including increased greenhouse gas accumulation in the atmosphere and aquatic eutrophication. The soil microbial community is the principal driver of soil N cycling; thus, improved understanding of microbial community responses to urea addition has widespread implications. We used next-generation amplicon sequencing of the 16S rRNA gene to characterize bacterial and archaeal communities in eight contrasting agricultural soil types amended with 0, 100, or 500 μg N g-1 of urea and incubated for 21 days. We hypothesized that urea amendment would have common, direct effects on the abundance and diversity of members of the microbial community associated with nitrification, across all soils, and would further affect the broader heterotrophic community resulting in decreased diversity and variation in abundances of specific taxa. Significant (P < 0.001) differences in bacterial community diversity and composition were observed by site, but amendment with only the greatest urea concentration significantly decreased Shannon indices. Expansion in the abundances of members of the families Microbacteriaceae, Chitinophagaceae, Comamonadaceae, Xanthomonadaceae, and Nitrosomonadaceae were also consistently observed among all soils (linear discriminant analysis score ≥ 3.0). Analysis of nitrifier genera revealed diverse, soil-specific distributions of oligotypes (strains), but few were correlated with nitrification gene abundances that were reported in a previous study. Our results suggest that the majority of the bacterial and archaeal community are likely unassociated with N cycling, but are significantly negatively impacted by urea application. Furthermore, these results reveal that amendment with high concentrations of urea may reduce nitrifier diversity, favoring specific strains, specifically those within the nitrifying genera

  10. Effects of industrial and agricultural waste amendment on soil greenhouse gas production in a paddy field in Southeastern China

    NASA Astrophysics Data System (ADS)

    Wang, Weiqi; Neogi, Suvadip; Lai, Derrick Y. F.; Zeng, Congsheng; Wang, Chun; Zeng, Dongping

    2017-09-01

    Controlling the production and subsequent emissions of greenhouse gases (GHGs) from paddy fields is crucial to minimize the climatic impacts arising from crop production. The application of chemical or biological amendments is one possible way to limit the production of GHGs in paddy soils. Yet, few existing studies have examined the impacts of applying fertilizers originated from industrial and agricultural wastes on soil GHG production and its governing factors in subtropical paddy fields. In this study, we examined the effects of various agricultural and industrial amendments, including biochar, steel slag, shell slag, gypsum slag, and slag-derived silicate and calcium fertilizers, on the production potential of GHGs in an early paddy field in southeast China. The mean CO2 production rates from soils amended with steel slag as well as silicate and calcium fertilizers were significantly higher than those of the controls by 13.4% and 18.6%, respectively (P < 0.05). Mean soil CH4 production rates from the plots amended with steel slag, biochar, shell slag, and gypsum slag were significantly lower than those of the controls by 42.5%, 36.1%, 60.8%, and 61.8%, respectively (P < 0.05). Meanwhile, we found no significant difference in mean soil N2O production rates between the control and any of the treatments (P > 0.05). Overall, the soil production rate of CO2 was positively correlated with that of CH4 (P < 0.05), but negatively correlated with that of N2O (P < 0.05). When compared to the controls, the ratio of soil CO2:CH4 production increased significantly in the plots receiving biochar, and silicate and calcium fertilizer amendments (P < 0.05), while that of CO2:N2O production increased significantly only in the biochar-amended plots. Soil CH4:N2O production ratio decreased significantly in the plots amended with steel slag and gypsum slag, as compared to the controls (P < 0.05). Our results suggest that the application of biochar, shell slag and gypsum slag would

  11. [Effect of inorganic amendments on the stabilization of heavy metals in contaminated soils].

    PubMed

    Cao, Meng-hua; Zhu, Xi; Liu, Huang-cheng; Wang, Lin-ling; Chen, Jing

    2013-09-01

    Effects of single and mixed inorganic amendments on the stabilization of heavy metals in contaminated soils were investigated. Significant synergistic effects on the stabilization of Zn and Cu were observed with the mixed inorganic amendments of KH2PO4 and Ca(OH)2 in the laboratory test. In the field test, the stabilization ratios of Zn, Cu and Cd were 41.8%, 28.2% and 48.4%, respectively, with the dosage of 0.5 kg x m(-2). The growth of peanut was inhibited by the addition of the inorganic amendments. Meanwhile, the uptake of heavy metals was reduced in peanut.

  12. Soil amendments and Listeria monocytogenes and Salmonella newport survival on cucurbits

    USDA-ARS?s Scientific Manuscript database

    EMFSL conducts research on a variety of produce safety related issues. EMFSL is involved in determining what the appropriate interval is between application of manure and harvest of crops grown in manure-amended soils. EMFSL has also investigated commodities associated with recent outbreaks (canta...

  13. Effects of organic amendment on degradation of 1,3-dichloropropene and chloropicrin in soil

    USDA-ARS?s Scientific Manuscript database

    Soil fumigants 1,3-dichloropropene (1,3-D) and chloropicrin (CP), are promising alternatives to the phased-out methyl bromide. However, these fumigants are volatile organic compounds and contribute to air pollution from emissions. Organic amendment to soils has been found to reduce emissions by incr...

  14. Decreased water flowing from a forest amended with calcium silicate

    Treesearch

    Mark B. Green; Amey S. Bailey; Scott W. Bailey; John J. Battles; John L. Campbell; Charles T. Driscoll; Timothy J. Fahey; Lucie C. Lepine; Gene E. Likens; Scott V. Ollinger; Paul G. Schaberg

    2013-01-01

    Acid deposition during the 20th century caused widespread depletion of available soil calcium (Ca) throughout much of the industrialized world. To better understand how forest ecosystems respond to changes in a component of acidification stress, an 11.8-ha watershed was amended with wollastonite, a calcium silicate mineral, to restore available soil Ca to preindustrial...

  15. Microbial Diversity of a Mediterranean Soil and Its Changes after Biotransformed Dry Olive Residue Amendment

    PubMed Central

    Siles, José A.; Rachid, Caio T. C. C.; Sampedro, Inmaculada; García-Romera, Inmaculada; Tiedje, James M.

    2014-01-01

    The Mediterranean basin has been identified as a biodiversity hotspot, about whose soil microbial diversity little is known. Intensive land use and aggressive management practices are degrading the soil, with a consequent loss of fertility. The use of organic amendments such as dry olive residue (DOR), a waste produced by a two-phase olive-oil extraction system, has been proposed as an effective way to improve soil properties. However, before its application to soil, DOR needs a pre-treatment, such as by a ligninolytic fungal transformation, e.g. Coriolopsis floccosa. The present study aimed to describe the bacterial and fungal diversity in a Mediterranean soil and to assess the impact of raw DOR (DOR) and C. floccosa-transformed DOR (CORDOR) on function and phylogeny of soil microbial communities after 0, 30 and 60 days. Pyrosequencing of the 16S rRNA gene demonstrated that bacterial diversity was dominated by the phyla Proteobacteria, Acidobacteria, and Actinobacteria, while 28S-rRNA gene data revealed that Ascomycota and Basidiomycota accounted for the majority of phyla in the fungal community. A Biolog EcoPlate experiment showed that DOR and CORDOR amendments decreased functional diversity and altered microbial functional structures. These changes in soil functionality occurred in parallel with those in phylogenetic bacterial and fungal community structures. Some bacterial and fungal groups increased while others decreased depending on the relative abundance of beneficial and toxic substances incorporated with each amendment. In general, DOR was observed to be more disruptive than CORDOR. PMID:25058610

  16. Anaerobic digestion of municipal solid waste: Utility of process residues as a soil amendment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rivard, C.J.; Nagle, N.J.; Kay, B.D.

    1995-12-31

    Tuna processing wastes (sludges high in fat, oil, and grease [FOG]) and municipal solid waste (MSW) generated on Tutuila Island, American Samoa, represent an ongoing disposal challenge. The biological conversion of the organic fraction of these wastes to useful products, including methane and fertilizer-grade residue, through anaerobic high-solids digestion is currently in scale-up development. The suitability of the anaerobic digestion residues as a soil amendment was evaluated through extensive chemical analysis and greenhouse studies using corn as an indicator crop. Additionally, native Samoan soil was used to evaluate the specific application rates for the compost. Experiments established that anaerobic residuesmore » increase crop yields in direct proportion to increases in the application rate. Additionally, nutrient saturation was not demonstrated within the range of application rates evaluated for the Samoan soil. Beyond nutrient supplementation, organic residue amendment to Samoan soil imparts enhanced water and nutrient-binding capacities.« less

  17. Tropical soils degraded by slash-and-burn cultivation can be recultivated when amended with ashes and compost.

    PubMed

    Gay-des-Combes, Justine Marie; Sanz Carrillo, Clara; Robroek, Bjorn Jozef Maria; Jassey, Vincent Eric Jules; Mills, Robert Thomas Edmund; Arif, Muhammad Saleem; Falquet, Leia; Frossard, Emmanuel; Buttler, Alexandre

    2017-07-01

    In many tropical regions, slash-and-burn agriculture is considered as a driver of deforestation; the forest is converted into agricultural land by cutting and burning the trees. However, the fields are abandoned after few years because of yield decrease and weed invasion. Consequently, new surfaces are regularly cleared from the primary forest. We propose a reclamation strategy for abandoned fields allowing and sustaining re-cultivation. In the dry region of south-western Madagascar, we tested, according to a split-plot design, an alternative selective slash-and-burn cultivation technique coupled with compost amendment on 30-year-old abandoned fields. Corn plants ( Zea mays L.) were grown on four different types of soil amendments: no amendment (control), compost, ashes (as in traditional slash-and-burn cultivation), and compost + ashes additions. Furthermore, two tree cover treatments were applied: 0% tree cover (as in traditional slash-and-burn cultivation) and 50% tree cover (selective slash-and-burn). Both corn growth and soil fertility parameters were monitored during the growing season 2015 up to final harvest. The amendment compost + ashes strongly increased corn yield, which was multiplied by 4-5 in comparison with ashes or compost alone, reaching 1.5 t/ha compared to 0.25 and 0.35 t/ha for ashes and compost, respectively. On control plots, yield was negligible as expected on these degraded soils. Structural equation modeling evidenced that compost and ashes were complementary fertilizing pathways promoting soil fertility through positive effects on soil moisture, pH, organic matter, and microbial activity. Concerning the tree cover treatment, yield was reduced on shaded plots (50% tree cover) compared to sunny plots (0% tree cover) for all soil amendments, except ashes. To conclude, our results provide empirical evidence on the potential of recultivating tropical degraded soils with compost and ashes. This would help mitigating deforestation of the

  18. Comparison of EDTA and EDDS as potential soil amendments for enhanced phytoextraction of heavy metals.

    PubMed

    Meers, E; Ruttens, A; Hopgood, M J; Samson, D; Tack, F M G

    2005-02-01

    Phytoextraction has been proposed as an alternative remediation technology for soils polluted with heavy metals or radionuclides, but is generally conceived as too slow working. Enhancing the accumulation of trace pollutants in harvestable plant tissues is a prerequisite for the technology to be practically applicable. The chelating aminopolycarboxylic acid, ethylene diamine tetraacetate (EDTA), has been found to enhance shoot accumulation of heavy metals. However, the use of EDTA in phytoextraction may not be suitable due to its high environmental persistence, which may lead to groundwater contamination. This paper aims to assess whether ethylene diamine disuccinate (EDDS), a biodegradable chelator, can be used for enhanced phytoextraction purposes. A laboratory experiment was conducted to examine mobilisation of Cd, Cu, Cr, Ni, Pb and Zn into the soil solution upon application of EDTA or EDDS. The longevity of the induced mobilisation was monitored for a period of 40 days after application. Estimated effect half lives ranged between 3.8 and 7.5 days for EDDS, depending on the applied dose. The minimum observed effect half life of EDTA was 36 days, while for the highest applied dose no decrease was observed throughout the 40 day period of the mobilisation experiment. Performance of EDTA and EDDS for phytoextraction was evaluated by application to Helianthus annuus. Two other potential chelators, known for their biodegradability in comparison to EDTA, were tested in the plant experiment: nitrilo acetic acid (NTA) and citric acid. Uptake of heavy metals was higher in EDDS-treated pots than in EDTA-treated pots. The effects were still considered insufficiently high to consider efficient remediation. This may be partly due to the choice of timing for application of the soil amendment. Fixing the time of application at an earlier point before harvest may yield better results. NTA and citric acid induced no significant effects on heavy metal uptake.

  19. Reversible and irreversible sorption of agrochemicals in biochar amended soils: synergistic effects of heavy metals

    USDA-ARS?s Scientific Manuscript database

    Soil amendment of biochar products from thermochemical waste-to-energy conversion (slow/fast pyrolysis and gasification) of biomass has received considerable interests for both contaminated and agricultural sites. Recalcitrant nature of biochar manifests in their decade-long effectiveness in soil a...

  20. Influence of Organic Amendment and Compaction on Nutrient Dynamics in a Saturated Saline-Sodic Soil from the Riparian Zone.

    PubMed

    Miller, J J; Bremer, E; Curtis, T

    2016-07-01

    Cattle grazing in wet riparian pastures may influence nutrient dynamics due to nutrient deposition in feces and urine, soil compaction, and vegetation loss. We conducted a lab incubation study with a saline-sodic riparian soil to study nutrient (N, P, S, Fe, Mn, Cu, and Zn) dynamics in soil pore water using Plant Root Simulator (PRS) probes and release of nutrients into the overlying ponded water during flooding. The treatment factors were organic amendment (manure, roots, and unamended control), compaction (compacted, uncompacted), and burial time (3, 7, and 14 d). Amendment treatment had the greatest impact on nutrient dynamics, followed by burial time, whereas compaction had little impact. The findings generally supported our hypothesis that organic amendments should first increase nitrate loss, then increase Mn mobility, then Fe mobility and associated release of P, and finally increase sulfate loss. Declines in nitrate due to amendment addition were small because nitrate was at low levels in all treatments due to high denitrification potential instead of being released to soil pore water or overlying water. Addition of organic amendment strongly increased Mn and Fe concentrations in overlying water and of adsorbed Fe on PRS probes but only increased Mn on PRS probes on Day 3 due to subsequent displacement from ion exchange membranes. Transport of P to overlying water was increased by organic amendment addition but less so for manure than roots despite higher P on PRS probes. The findings showed that saline-sodic soils in riparian zones are generally a nutrient source for P and are a nutrient sink for N as measured using PRS probes after 3 to 7 d of flooding. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Comparative sorption and leaching study of the herbicides fluometuron and MCPA in a soil amended with biochar and other sorbents

    USDA-ARS?s Scientific Manuscript database

    Biochar is the solid residual remaining after the thermo-chemical transformation of biomass and, because of its numerous properties; it has been proposed to be used as soil amendment. In this work, the effect of soil amendment with six biochars from different feedstocks, production, and post-product...

  2. Persistence of spiromesifen in soil: influence of moisture, light, pH and organic amendment.

    PubMed

    Mate, Ch Jamkhokai; Mukherjee, Irani; Das, Shaon Kumar

    2015-02-01

    Persistence of spiromesifen in soil as affected by varying moisture, light, compost amendment, soil sterilization and pH in aqueous medium were studied. Degradation of spiromesifen in soil followed the first-order reaction kinetics. Effect of different moisture regimes indicated that spiromesifen dissipated faster in submerged soil (t 1/2 14.3-16.7 days) followed by field capacity (t 1/2 18.7-20.0 days), and dry soil (t 1/2 21.9-22.9 days). Dissipation was faster in sterilized submerged (t 1/2 17.7 days) than in sterilized dry (t 1/2 35.8 days). Photo spiromesifen metabolite was not detected under different moisture regimes. After 30 days, enol spiromesifen metabolite was detected under submerged condition and was below detectable limit (<0.001 μg g(-1)) after 90 days. Soil amendment compost (2.5 %) at field capacity enhanced dissipation of the insecticide, and half-life value was 14.3 against 22.4 days without compost amendment. Under different pH condition, residues persisted in water with half-life values 5.7 to 12.5 days. Dissipation in water was faster at pH 9.0 (t 1/2 5.7 days), followed by pH 4.0 (t 1/2 9.7 days) and pH 7.2 (t 1/2 12.5 days). Exposure of spiromesifen to different light conditions indicated that it was more prone to degradation under UV light (t 1/2 3-4 days) than sunlight exposure (t 1/2 5.2-8.1 days). Under sunlight exposure, photo spiromesifen metabolite was detected after 10 and 15 days as compared to 3 and 5 days under UV light exposure.

  3. Importance of Soil Amendments: Survival of Bacterial Pathogens in Manure and Compost Used as Organic Fertilizers.

    PubMed

    Sharma, Manan; Reynnells, Russell

    2016-08-01

    Biological soil amendments (BSAs) such as manure and compost are frequently used as organic fertilizers to improve the physical and chemical properties of soils. However, BSAs have been known to be a reservoir for enteric bacterial pathogens such as enterohemorrhagic Escherichia coli (EHEC), Salmonella spp., and Listeria spp. There are numerous mechanisms by which manure may transfer pathogens to growing fruits and vegetables, and several outbreaks of infections have been linked to manure-related contamination of leafy greens. In the United States several commodity-specific guidelines and current and proposed federal rules exist to provide guidance on the application of BSAs as fertilizers to soils, some of which require an interval between the application of manure to soils and the harvest of fruits and vegetables. This review examines the survival, persistence, and regrowth/resuscitation of bacterial pathogens in manure, biosolids, and composts. Moisture, along with climate and the physicochemical properties of soil, manure, or compost, plays a significant role in the ability of pathogens to persist and resuscitate in amended soils. Adaptation of enteric bacterial pathogens to the nonhost environment of soils may also extend their persistence in manure- or compost-amended soils. The presence of antibiotic-resistance genes in soils may also be increased by manure application. Overall, BSAs applied as fertilizers to soils can support the survival and regrowth of pathogens. BSAs should be handled and applied in a manner that reduces the prevalence of pathogens in soils and the likelihood of transfer of food-borne pathogens to fruits and vegetables. This review will focus on two BSAs-raw manure and composted manure (and other feedstocks)-and predominantly on the survival of enteric bacterial pathogens in BSAs as applied to soils as organic fertilizers.

  4. Short-term impacts of soil amendments on belowground C cycling and soil nutrition in two contrasting Pinus taeda L. genotypes

    Treesearch

    Michael C Tyree; John R Seiler; Christopher Maier

    2011-01-01

    We monitored two Pinus taeda L. genotypes, planted in 170 L lysimeters, subjected to different combinations of fertilization and logging residue (LR) incorporation for 1 year. The objectives were to elucidate how soil amendments modified soil biological properties and belowground C cycling, and secondly, to determine if planting of contrasting genotypes have a...

  5. Natural attenuation of toxic metal phytoavailability in 35-year-old sewage sludge-amended soil.

    PubMed

    Tai, Yiping; Li, Zhian; Mcbride, Murray B

    2016-04-01

    Toxic heavy metals persist in agricultural soils and ecosystem for many decades after their application as contaminants in sewage sludge and fertilizer products This study assessed the potential long-term risk of cadmium (Cd), lead (Pb), zinc (Zn), and copper (Cu) in land-applied sewage sludge to food crop contamination. A sewage sludge-amended soil (SAS) aged in the field more than 35 years was used in a greenhouse pot experiment with leafy vegetables (lettuce and amaranth) having strong Cd and Zn accumulation tendencies. Soil media with variable levels of available Cd, Zn, and Cu (measured using 0.01 M CaCl2 extraction) were prepared by diluting SAS with several levels of uncontaminated control soil. Despite long-term aging in the field, the sludge site soil still retains large reserves of heavy metals, residual organic matter, phosphorus, and other nutrients, but its characteristics appear to have stabilized over time. Nevertheless, lettuce and amaranth harvested from the sludge-treated soil had undesirable contents of Cd and Zn. The high plant uptake efficiency for Cd and Zn raises a concern regarding the quality and safety of leafy vegetables in particular, when these crops are grown on soils that have been amended heavily with sewage sludge products at any time in their past.

  6. Effects of nitrogen and biochar amendment on soil methane concentration profiles and diffusion in a rice-wheat annual rotation system

    NASA Astrophysics Data System (ADS)

    Xu, Xin; Wu, Zhen; Dong, Yubing; Zhou, Ziqiang; Xiong, Zhengqin

    2016-12-01

    The CH4 emissions from soil were influenced by the changeable CH4 concentrations and diffusions in soil profiles, but that have been subjected to nitrogen (N) and biochar amendment over seasonal and annual time frames. Accordingly, a two-year field experiment was conducted in southeastern China to determine the amendment effects on CH4 concentrations and diffusive effluxes as measured by a multilevel sampling probe in paddy soil during two cycles of rice-wheat rotations. The results showed that the top 7-cm soil layers were the primary CH4 production sites during the rice-growing seasons. This layer acted as the source of CH4 generation and diffusion, and the deeper soil layers and the wheat season soil acted as the sink. N fertilization significantly increased the CH4 concentration and diffusive effluxes in the top 7-cm layers during the 2013 and 2014 rice seasons. Following biochar amendment, the soil CH4 concentrations significantly decreased during the rice season in 2014, relative to the single N treatment. Moreover, 40 t ha-1 biochar significantly decreased the diffusive effluxes during the rice seasons in both years. Therefore, our results showed that biochar amendment is a good strategy for reducing the soil profile CH4 concentrations and diffusive effluxes induced by N in paddy fields.

  7. Effects of nitrogen and biochar amendment on soil methane concentration profiles and diffusion in a rice-wheat annual rotation system.

    PubMed

    Xu, Xin; Wu, Zhen; Dong, Yubing; Zhou, Ziqiang; Xiong, Zhengqin

    2016-12-08

    The CH 4 emissions from soil were influenced by the changeable CH 4 concentrations and diffusions in soil profiles, but that have been subjected to nitrogen (N) and biochar amendment over seasonal and annual time frames. Accordingly, a two-year field experiment was conducted in southeastern China to determine the amendment effects on CH 4 concentrations and diffusive effluxes as measured by a multilevel sampling probe in paddy soil during two cycles of rice-wheat rotations. The results showed that the top 7-cm soil layers were the primary CH 4 production sites during the rice-growing seasons. This layer acted as the source of CH 4 generation and diffusion, and the deeper soil layers and the wheat season soil acted as the sink. N fertilization significantly increased the CH 4 concentration and diffusive effluxes in the top 7-cm layers during the 2013 and 2014 rice seasons. Following biochar amendment, the soil CH 4 concentrations significantly decreased during the rice season in 2014, relative to the single N treatment. Moreover, 40 t ha -1 biochar significantly decreased the diffusive effluxes during the rice seasons in both years. Therefore, our results showed that biochar amendment is a good strategy for reducing the soil profile CH 4 concentrations and diffusive effluxes induced by N in paddy fields.

  8. Acid precipitation and forest soils

    Treesearch

    C. O. Tamm

    1976-01-01

    Many soil processes and properties may be affected by a change in chemical climate such as that caused by acidification of precipitation. The effect of additions of acid precipitation depends at first on the extent to which this acid is really absorbed by the soil and on the changes in substances with actual or potential acidity leaving the soil. There is for instance...

  9. Soil physical and hydrological properties as affected by long-term addition of various organic amendments

    NASA Astrophysics Data System (ADS)

    Eden, Marie; Völkel, Jörg; Mercier, Vincent; Labat, Christophe; Houot, Sabine

    2014-05-01

    The use of organic residues as soil amendments in agriculture not only reduces the amount of waste needing to be disposed of; it may also lead to improvements in soil properties, including physical and hydrological ones. The present study examines a long-term experiment called "Qualiagro", run jointly by INRA and Veolia Environment in Feucherolles, France (near Paris). It was initiated in 1998 on a loess-derived silt loam (787 g/kg silt, 152 g/kg clay) and includes ten treatments: four types of organic amendments and a control (CNT) each at two levels of mineral nitrogen (N) addition: minimal (Nmin) and optimal (Nopt). The amendments include three types of compost and farmyard manure (FYM), which were applied every other year at a rate of ca. 4 t carbon ha-1. The composts include municipal solid waste compost (MSW), co-compost of green wastes and sewage sludge (GWS), and biowaste compost (BIO). The plots are arranged in a randomized block design and have a size of 450 m²; each treatment is replicated four times (total of 40 plots). Ca. 15 years after the start of the experiment soil organic carbon (OC) had continuously increased in the amended plots, while it remained stable or decreased in the control plots. This compost- or manure-induced increase in OC plays a key role, affecting numerous dependant soil properties like bulk density, porosity and water retention. The water holding capacity (WHC) of a soil is of particular interest to farmers in terms of water supply for plants, but also indicates soil quality and functionality. Addition of OC may affect WHC in different ways: carbon-induced aggregation may increase larger-pore volume and hence WHC at the wet end while increased surface areas may lead to an increased retention of water at the dry end. Consequently it is difficult to predict (e.g. with pedotransfer functions) the impact on the amount of water available for plants (PAW), which was experimentally determined for the soils, along with the entire range

  10. In Situ Evaluation of Crop Productivity and Bioaccumulation of Heavy Metals in Paddy Soils after Remediation of Metal-Contaminated Soils.

    PubMed

    Kim, Shin Woong; Chae, Yooeun; Moon, Jongmin; Kim, Dokyung; Cui, Rongxue; An, Gyeonghyeon; Jeong, Seung-Woo; An, Youn-Joo

    2017-02-15

    Soils contaminated with heavy metals have been reused for agricultural, building, and industrial uses following remediation. This study assesses plant growth and bioaccumulation of heavy metals following remediation of industrially contaminated soil. The soil was collected from a field site near a nonferrous smelter and was subjected to laboratory- and field-scale studies. Soil from the contaminated site was remediated by washing with acid or mixed with soil taken from a distant uncontaminated site. The activities of various soil exoenzymes, the rate of plant growth, and the bioaccumulations of six heavy metals were measured to assess the efficacy of these bioremediation techniques. Growth of rice (Oryza sativa) was unaffected in acid-washed soil or the amended soil compared to untreated soil from the contaminated site. The levels of heavy metals in the rice kernels remained within safe limits in treated and untreated soils. Rice, sorghum (Sorghum bicolor), and wheat (Triticum aestivum) cultivated in the same soils in the laboratory showed similar growth rates. Soil exoenzyme activities and crop productivity were not affected by soil treatment in field experiments. In conclusion, treatment of industrially contaminated soil by acid washing or amendment did not adversely affect plant productivity or lead to increased bioaccumulation of heavy metals in rice.

  11. Nitrogen fertilizer recommendations for corn grown on soils amended with oily food waste.

    PubMed

    Rashid, M T; Voroney, R P

    2005-01-01

    Soil and plant indices of soil fertility status have traditionally been developed using conventional soil and crop management practices. Data on managing N fertilizer for corn (Zea mays L.) produced on soils amended with C-rich organic materials, such as oily food waste (OFW) is scarce. Identification of a reliable method for making N fertilizer recommendations under these conditions is imperative. The objective of this research was to evaluate soil NO(3)-N (0- to 30-cm depth) at preplant and presidedress (PSNT) times of sampling for predicting N requirements for corn grown on fields receiving OFW. Experiments were conducted at two locations in Ontario, Canada over 3 yr (1995-1997) where OFW was applied at different rates (0, 10, and 20 Mg ha(-1)), times (fall and spring), and slope positions (upper, mid, and lower) within the same field. Presidedress soil NO(3)-N contents were higher compared with preplant time of sampling under all OFW management conditions. Corn grain yields were significantly affected by OFW management and N fertilizer application rates. Maximum economic rate of N application (MERN) varied depending on OFW management conditions. Presidedress soil NO(3)-N contents had a higher inverse relationship with MERN (r = -0.88) compared with soil NO(3)-N at preplant (r = -0.74) time of sampling. A linear regression model (Y = 180.1 - 8.22 NO(3)-N at PSNT) is proposed for making N fertilizer recommendations to corn grown on soils amended with OFW in this geographical region.

  12. Linking N2O emissions from biochar-amended soil to the structure and function of the N-cycling microbial community

    PubMed Central

    Harter, Johannes; Krause, Hans-Martin; Schuettler, Stefanie; Ruser, Reiner; Fromme, Markus; Scholten, Thomas; Kappler, Andreas; Behrens, Sebastian

    2014-01-01

    Nitrous oxide (N2O) contributes 8% to global greenhouse gas emissions. Agricultural sources represent about 60% of anthropogenic N2O emissions. Most agricultural N2O emissions are due to increased fertilizer application. A considerable fraction of nitrogen fertilizers are converted to N2O by microbiological processes (that is, nitrification and denitrification). Soil amended with biochar (charcoal created by pyrolysis of biomass) has been demonstrated to increase crop yield, improve soil quality and affect greenhouse gas emissions, for example, reduce N2O emissions. Despite several studies on variations in the general microbial community structure due to soil biochar amendment, hitherto the specific role of the nitrogen cycling microbial community in mitigating soil N2O emissions has not been subject of systematic investigation. We performed a microcosm study with a water-saturated soil amended with different amounts (0%, 2% and 10% (w/w)) of high-temperature biochar. By quantifying the abundance and activity of functional marker genes of microbial nitrogen fixation (nifH), nitrification (amoA) and denitrification (nirK, nirS and nosZ) using quantitative PCR we found that biochar addition enhanced microbial nitrous oxide reduction and increased the abundance of microorganisms capable of N2-fixation. Soil biochar amendment increased the relative gene and transcript copy numbers of the nosZ-encoded bacterial N2O reductase, suggesting a mechanistic link to the observed reduction in N2O emissions. Our findings contribute to a better understanding of the impact of biochar on the nitrogen cycling microbial community and the consequences of soil biochar amendment for microbial nitrogen transformation processes and N2O emissions from soil. PMID:24067258

  13. Effect of some amendments on leachate properties of a calcareous saline- sodic soil: A laboratory experiment

    NASA Astrophysics Data System (ADS)

    Yazdanpanah, Najme; Mahmoodabadi, Majid

    2010-05-01

    Soil salinity and sodicity are escalating problems worldwide, especially in Iran since 90 percent of the country is located in arid and semi-arid. Reclamation of sodic soils involves replacement of exchangeable Na by Ca. While some researches have been undertaken in the controllable laboratory conditions using soil column with emphasis on soil properties, the properties of effluent as a measure of soil reclamation remain unstudied. In addition, little attention has been paid to the temporal variability of effluent quality. The objective of this study was to investigate the effect of different amendments consist of gypsum, manure, pistachio residue, and their combination for ameliorating a calcareous saline sodic soil. Temporal variability of effluent properties during reclamation period was studied, as well. A laboratory experiment was conducted to evaluate the effect of different amendments using soil columns. The amendment treatments were: control, manure, pistachio residue, gypsum powder (equivalent of gypsum requirement), manure+gypsum and pistachio residue+gypsum, which were applied once in the beginning of the experiment. The study was performed in 120 days period and totally four irrigation treatments were supplied to each column. After irrigations, the effluent samples were collected every day at the bottom of the soil columns and were analyzed. The results show that for all treatments, cations (e.g. Ca, Mg, Na and K) in the outflow decreased with time, exponentially. Manure treatment resulted in highest rate of Ca, Mg, Na leaching from soil solution, in spite of the control which had the lowest rate. In addition, pistachio residue had the most effect on K leaching. Manure treatment showed the most EC and SAR in the leachate, while gypsum application leads to the least rate of them. The findings of this research reveal different rates of cations leaching from soil profile, which is important in environmental issues. Keywords: Saline sodic soil, Reclamation

  14. Effect of organic amendments on quality indexes in an italian agricultural soil

    NASA Astrophysics Data System (ADS)

    Scotti, R.; Rao, M. A.; D'Ascoli, R.; Scelza, R.; Marzaioli, R.; Rutigliano, F. A.; Gianfreda, L.

    2009-04-01

    Intensive agricultural practices can determine a decline in soil fertility which represents the main constraint to agricultural productivity. In particular, the progressive reduction in soil organic matter, without an adequate restoration, may threaten soil fertility and agriculture sustainability. Some soil management practices can improve soil quality by adding organic amendments as alternative to the sole use of mineral fertilizers for increasing plant quality and growth. A large number of soil properties can be used to define changes in soil quality. In particular, although more emphasis has been given in literature to physical and chemical properties, biological properties, strictly linked to soil fertility, can be valid even more sensitive indicators. Among these, soil enzyme activities and microbial biomass may provide an "early warning" of soil quality and health changes. The aim of this work was to study the effect of preventive sterilization treatment and organic fertilization on enzymatic activities (dehydrogenase, arylsulphatase, beta-glucosidase, phosphatase, urease) and microbial biomass C in an agricultural soil under crop rotation. The study was carried out on an agricultural soil sited in Campania region (South Italy). At the beginning of experiment sterilizing treatments to control soilborne pathogens and weeds were performed by solarization and calcium cyanamide addition to soil. Organic fertilization was carried out by adding compost from vegetable residues, ricin seed exhaust (Rigen) and straw, singly or in association. Three samplings were performed at three different stages of crop rotation: I) September 2005, immediately after the treatments; II) December 2005, after a lettuce cycle; III) January 2007, after peppers and lettuce cycles. The soil sampling followed a W scheme, with five sub-samples for each plot. Soils were sieved at 2 mm mesh and air dried to determine physical and chemical properties; in addition a suitable amount of soils

  15. Factors influencing As(V) stabilization in the mine soils amended with iron-rich materials.

    PubMed

    Kim, Mijin; Kim, Juhee; Kim, Minhee; Kim, Yong-Seong; Nam, Seung Mo; Moon, Deok Hyun; Hyun, Seunghun

    2017-09-04

    Chemical stability of As(V) in amended mine-impacted soils was assessed according to functions of incubation period (0, 1, 2, 4, and 6 months), amendment dose (2.5 and 5%), and application timing (0 and 3rd month). Six soils contaminated with 26-209 mg kg -1 of As(V) were collected from two abandoned mine sites and were treated with two alkaline iron-rich materials (mine discharge sludge (MS) and steel-making slag (SS)). Seventeen to 23% of As(V) in soils was labile. After each designated time, As(V) stability was assessed by the labile fractions determined with sequential extraction procedures (F1-F5). Over 6 months, a reduction (26.9-70.4%) of the two labile fractions (F1 and F2) and a quantitative increase (7.4-29.9%) of As(V) in F3 were observed (r 2  = 0.956). Two recalcitrant fractions (F4 and F5) remained unchanged. Temporal change of As(V) stability in a sample was well described by the two-domain model (k fast , k slow , and F fast ). The stabilization (%) correlated well with the fast-stabilizing domain (F fast ), clay content (%), and Fe oxide content (mg kg -1 ), but correlated poorly with kinetic rate constants (k fast and k slow ). Until the 3rd month, the 2.5%-MS amended sample resulted in lower As(V) stabilization (25-40%) compared to the 5% sample (50-60%). However, the second 2.5% MS addition on the 2.5% sample upon the lapse of the 3rd month led to a substantial reduction (up to 38%) of labile As(V) fraction in the following 4th and 6th months. As a result, an additional 15-25% of As(V) stability was obtained when splitting the amendment dose into 3-month intervals. In conclusion, the As(V) stabilization by Fe-rich amendment is time-dependent and its efficacy can be improved by optimizing the amendment dose and its timing.

  16. Effect of Simulated Weathering and Aging of TNT in Amended Sandy Loam Soil on Toxicity to the Enchytraeid Worm, Enchytreaeus Crypticus

    DTIC Science & Technology

    2006-05-01

    high bioavailability of organic compounds. However, amended SSL soil was analyzed for presence of metabolic transformation products from nitroaromatic...Phillips, C.; Checkai, R. 1999. Comparison of malathion toxicity using enchytraeid reproduction test and earthworm toxicity test in different soil ...OF TNT IN AMENDED SANDY LOAM SOIL ON TOXICITY TO THE ENCHYTRAEID WORM, ENCHYTRAEUS CRYPTICUS Roman G. Kuperman Ronald T. Checkai Michael Simini

  17. Feather hydrolysate from Streptomyces sampsonii GS 1322: A potential low cost soil amendment.

    PubMed

    Jain, Richa; Jain, Aakanchha; Rawat, Neha; Nair, Meera; Gumashta, Raghvendra

    2016-06-01

    Process parameters for obtaining hydrolysate from hen feathers, i.e., initial pH (5.0-9.0) and incubation period (1-6 day), were set and studied, using Streptomyces sampsonii GS 1322 in submerged and solid state conditions. Under submerged conditions, complete hydrolysis of feathers was observed on fifth day [initial pH 8.0, 28 ± 2°C, shaking (150 rpm)] with release of soluble protein (2985 μg ml(-1)) and amino acids (2407 μg ml(-1)). Cell free hydrolysate showed hydrolysis of casein (18 mm), gelatin (26 mm), collagen (31 mm), hemoglobin (23 mm) and Tween 80 (35 mm) while 445 U keratinase activity. Total soluble protein reached 5 mg ml(-1) in solid state conditions. During Pot experimentation using barren agriculture soil the effect of feather hydrolysate on wheat crop were recorded. Significant increase (p<0.01) in wheat seed germination was observed in treated soils as compared to untreated. Treatment significantly increased plant height from 30 to 60 days and 30-90 days (p<0.001). Treated soil showed an increase in total microbial count, proteolytic activity, phosphate solubilizing bacteria and ammonifying bacteria, whereas pathogenic fungi load was reduced. S. sampsonii GS 1322 can be used for bio-processing of poultry wastes yielding feather hydrolysate rich in proteins and amino acids for development of low-cost organic amendment to accelerate wheat crop growth in barren agricultural land. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  18. Soil amendments effects on radiocesium translocation in forest soils.

    PubMed

    Sugiura, Yuki; Ozawa, Hajime; Umemura, Mitsutoshi; Takenaka, Chisato

    2016-12-01

    We conducted an experiment to investigate the potential of phytoremediation by soil amendments in a forest area. To desorb radiocesium ( 137 Cs) from variable charges in the soil, ammonium sulfate (NH 4 + ) and elemental sulfur (S) (which decrease soil pH) were applied to forest soil collected from contaminated area at a rate of 40 and 80 g/m 2 , respectively. A control condition with no soil treatment was also considered. We defined four groups of aboveground conditions: planted with Quercus serrata, planted with Houttuynia cordata, covered with rice straw as litter, and unplanted/uncovered (control). Cultivation was performed in a greenhouse with a regular water supply for four months. Following elemental sulfur treatment, soil pH values were significantly lower than pH values following ammonium sulfate treatment and no treatment. During cultivation, several plant species germinated from natural seeds. No clear differences in aboveground tissue 137 Cs concentrations in planted Q. serrata and H. cordata were observed among the treatments. However, aboveground tissue 137 Cs concentration values in the germinated plants following elemental sulfur treatment were higher than the values following the ammonium sulfate treatment and no treatment. Although biomass values for Q. serrata, H. cordata, and germinated plants following elemental sulfur treatment tended to be low, the total 137 Cs activities in the aboveground tissue of germinated plants were higher than those following ammonium sulfate treatment and no treatment in rice straw and unplanted conditions. Although no significant differences were observed, 137 Cs concentrations in rice straw following ammonium sulfate and elemental sulfur treatments tended to be higher than those in the control case. The results of this study indicate that elemental sulfur lowers the soil pH for a relatively long period and facilitates 137 Cs translocation to newly emerged and settled plants or litter, but affects plant growth in

  19. Determination of polycyclic aromatic hydrocarbons in biochar and biochar amended soil

    USDA-ARS?s Scientific Manuscript database

    A method for the determination of the 16 USEPA polycyclic aromatic hydrocarbons (PAHs) in biochar and soil amended with biochar was developed. Samples were Soxhlet extracted with acetone:cyclohexane 1:1, and PAHs were analysed by GC-MS after silica gel clean-up. In a comparative study based on reflu...

  20. Biochar soil amendments as a tool for climate change adaptation in PNW agriculture

    NASA Astrophysics Data System (ADS)

    Phillips, C. L.; Trippe, K. M.; Murphy, B. A.; Beovich, A. V.; Griffith, S. M.

    2015-12-01

    Loss of snow pack, changing hydrographs, and increased temperatures and irrigation demands as a result of climate change all threaten to create transformational drought for growers in the Pacific Northwest. One approach for adapting to drought is to improve moisture retention through soil management practices. Recent efforts at the FSCRU to develop on-farm power have produced a biochar from gasification of seed mill waste that may prove useful as a tool for drought adaption. Testing of this biochar revealed that it contains no toxic elements, making it suitable as a soil amendment, and additions of 20 tonnes ha-1 in dryland wheat system showed improved soil moisture and yield increases of 250%. Persistent but weaker impacts were observed in growing years 2 and 3 following the biochar amendments. Here we present results from a series of laboratory and field studies characterizing how grass seed screening biochar, which is produced from a regionally abundant feedstock, impacted soil hydraulic and thermal properties, soil chemistry, and plant growth. Because of the liming qualities of gasified biochar, the greatest growth benefits are likely to be realized in acidified soils, a growing problem in the PNW. Although the persistence of biochar impacts in soil is still unknown, our results indicate that gasified biochar, particularly when utilized as part of a system of on-farm power production, waste reduction, and nutrient recycling, can improve agricultural sustainability in the context of climate change.

  1. Co-digestion of agricultural and municipal waste to produce energy and soil amendment.

    PubMed

    Macias-Corral, Maritza A; Samani, Zohrab A; Hanson, Adrian T; Funk, Paul A

    2017-09-01

    In agriculture, manure and cotton gin waste are major environmental liabilities. Likewise, grass is an important organic component of municipal waste. These wastes were combined and used as substrates in a two-phase, pilot-scale anaerobic digester to evaluate the potential for biogas (methane) production, waste minimisation, and the digestate value as soil amendment. The anaerobic digestion process did not show signs of inhibition. Biogas production increased during the first 2 weeks of operation, when chemical oxygen demand and volatile fatty acid concentrations and the organic loading rate to the system were high. Chemical oxygen demand from the anaerobic columns remained relatively steady after the first week of operation, even at high organic loading rates. The experiment lasted about 1 month and produced 96.5 m 3 of biogas (68 m 3 of CH 4 ) per tonne of waste. In terms of chemical oxygen demand to methane conversion efficiency, the system generated 62% of the theoretical methane production; the chemical oxygen demand/volatile solids degradation rate was 62%, compared with the theoretical 66%. The results showed that co-digestion and subsequent digestate composting resulted in about 60% and 75% mass and volume reductions, respectively. Digestate analysis showed that it can be used as a high nutrient content soil amendment. The digestate met Class A faecal coliform standards (highest quality) established in the United States for biosolids. Digestion and subsequent composting concentrated the digestate nitrogen, phosphorus, and potassium content by 37%, 24%, and 317%, respectively. Multi-substrate co-digestion is a practical alternative for agricultural waste management, minimisation of landfill disposal, and it also results in the production of valuable products.

  2. Effect of biochar amendment on the control of soil sulfonamides, antibiotic-resistant bacteria, and gene enrichment in lettuce tissues.

    PubMed

    Ye, Mao; Sun, Mingming; Feng, Yanfang; Wan, Jinzhong; Xie, Shanni; Tian, Da; Zhao, Yu; Wu, Jun; Hu, Feng; Li, Huixin; Jiang, Xin

    2016-05-15

    Considering the potential threat of vegetables growing in antibiotic-polluted soil with high abundance of antibiotic-resistant genes (ARGs) against human health through the food chain, it is thus urgent to develop novel control technology to ensure vegetable safety. In the present work, pot experiments were conducted in lettuce cultivation to assess the impedance effect of biochar amendment on soil sulfonamides (SAs), antibiotic-resistant bacteria (ARB), and ARG enrichment in lettuce tissues. After 100 days of cultivation, lettuce cultivation with biochar amendment exhibited the greatest soil SA dissipation as well as the significant improvement of lettuce growth indices, with residual soil SAs mainly existing as the tightly bound fraction. Moreover, the SA contents in roots and new/old leaves were reduced by one to two orders of magnitude compared to those without biochar amendment. In addition, isolate counts for SA-resistant bacterial endophytes in old leaves and sul gene abundances in roots and old leaves also decreased significantly after biochar application. However, neither SA resistant bacteria nor sul genes were detected in new leaves. It was the first study to demonstrate that biochar amendment can be a practical strategy to protect lettuce safety growing in SA-polluted soil with rich ARB and ARGs. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Mobility of Pb, Cu, and Zn in the phosphorus-amended contaminated soils under simulated landfill and rainfall conditions.

    PubMed

    Cao, Xinde; Liang, Yuan; Zhao, Ling; Le, Huangying

    2013-09-01

    Phosphorus-bearing materials have been widely applied in immobilization of heavy metals in contaminated soils. However, the study on the stability of the initially P-induced immobilized metals in the contaminated soils is far limited. This work was conducted to evaluate the mobility of Pb, Cu, and Zn in two contrasting contaminated soils amended with phosphate rock tailing (PR) and triple superphosphate fertilizer (TSP), and their combination (P + T) under simulated landfill and rainfall conditions. The main objective was to determine the stability of heavy metals in the P-treated contaminated soils in response to the changing environment conditions. The soils were amended with the P-bearing materials at a 2:1 molar ratio of P to metals. After equilibrated for 2 weeks, the soils were evaluated with the leaching procedures. The batch-based toxicity characteristic leaching procedure (TCLP) was conducted to determine the leachability of heavy metals from both untreated and P-treated soils under simulated landfill condition. The column-based synthetic precipitation leaching procedure (SPLP) were undertaken to measure the downward migration of metals from untreated and P-treated soils under simulated rainfall condition. Leachability of Pb, Cu, and Zn in the TCLP extract followed the order of Zn > Cu > Pb in both soils, with the organic-C- and clay-poor soil showing higher metal leachability than the organic-C- and clay-rich soil. All three P treatments reduced leachability of Pb, Cu, and Zn by up to 89.2, 24.4, and 34.3 %, respectively, compared to the untreated soil, and TSP revealed more effectiveness followed by P + T and then PR. The column experiments showed that Zn had the highest downward migration upon 10 pore volumes of SPLP leaching, followed by Pb and then Cu in both soils. However, migration of Pb and Zn to subsoil and leachate were inhibited in the P-treated soil, while Cu in the leachate was enhanced by P treatment in the organic

  4. Environmental risk assessment of the use of different organic wastes as soil amendments

    NASA Astrophysics Data System (ADS)

    Alvarenga, Paula; Palma, Patrícia; Mourinha, Clarisse; Farto, Márcia; Cunha-Queda, Ana Cristina; Natal-da-Luz, Tiago; Sousa, José Paulo

    2013-04-01

    The use of organic wastes in agriculture is considered a way of maintaining or restoring the quality of soils, enlarging the slow cycling soil organic carbon pool. However, a wide variety of undesired substances, such as potentially trace elements and organic contaminants, can have adverse effects on the environment. That fact was highlighted by the Proposal for a Soil Framework Directive, which recognized that "soil degradation or soil improvements have a major impact on other areas, (…) such as surface waters and groundwater, human health, climate change, protection of nature and biodiversity, and food safety". Taking that into account, the research project "ResOrgRisk" aims to assess the environmental risk involved in the use of different organic wastes as soil amendments, evidencing their benefits and constraints, and defining the most suitable tests to reach such assessment. The organic wastes selected for this purpose were: sewage sludge, limed, not limed, and co-composted with agricultural wastes, agro-industrial sludge, mixed municipal solid waste compost, compost produced from organic farming residues, and pig slurry digestate. Whereas threshold values for heavy metals in sludge used for agriculture have been set by the European Commission, actually there is no definitive European legislation for organic contaminants. Guide values for some organic contaminants (e.g. polychlorinated biphenyls - PCBs, and polycyclic aromatic hydrocarbons - PAHs) have been adopted at national level by many European countries, such as Portugal. These values should be taken into account when assessing the risk involved in the use of organic wastes as soil amendments. However, chemical analysis of organic waste often gives scarce information because it does not include possible interactions between chemicals. Furthermore, an exhaustive identification and quantification of all substances is impractical. In this study, ecotoxicological tests (comprising solid and aquatic phases

  5. The concentration and changes in freely dissolved polycyclic aromatic hydrocarbons in biochar-amended soil.

    PubMed

    Oleszczuk, Patryk; Kuśmierz, Marcin; Godlewska, Paulina; Kraska, Piotr; Pałys, Edward

    2016-07-01

    The presence of polycyclic aromatic hydrocarbons (PAHs) in biochars hinders their environmental use. The aim of this study was to determine the freely dissolved (Cfree) PAH content in soil amended with biochar in a long-term (851 days) field experiment. Biochar was added to the soil at a rate of 30 and 45 t/ha. The addition of biochar to the soil resulted in a decrease in Σ13 Cfree PAHs by 25 and 22%, in the soil with the addition of biochar at the rate of 30 and 45 t/ha, respectively. As far as individual PAHs are concerned, in most cases a reduction in Cfree was also observed (from 3.6 to 66%, depending on the biochar rate). During the first 105 days of the experiment, the content of Σ13 Cfree in the biochar-amended soil significantly decreased by 26% (30 t/ha) and 36% (45 t/ha). After this period of time until the end of the experiment, no significant changes in Cfree were observed, regardless of the biochar rate. However, the behavior of individual PAH groups differed depending on the number of rings and experimental treatment. Ultimately, after 851 days of the experiment the content of Σ13 Cfree PAHs was lower by 29% (30 t/ha) and 35% (45 t/ha) compared to the beginning of the study as well as lower by 40% (30 t/ha) and 42% (45 t/ha) than in the control soil. The log KTOC coefficients calculated for the biochar-amended soils were higher immediately after adding biochar and subsequently they gradually decreased, indicating the reduced strength of the interaction between biochar and the studied PAHs. The obtained results show that the addition of biochar to soil does not create a risk in terms of the content of Cfree PAHs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Sorption-desorption equilibrium and diffusion of tetracycline in poultry litter and municipal biosolids soil amendments.

    PubMed

    D'Angelo, E

    2017-12-01

    Tetracycline (TET) is commonly used to treat bacterial diseases in humans and chickens (Gallus gallus domesticus), is largely excreted, and is found at elevated concentrations in treated sewage sludge (biosolids) and poultry litter (excrement plus bedding materials). Routine application of these nutrient-and carbon-enriched materials to soils improves fertility and other characteristics, but the presence of antibiotics (and other pharmaceuticals) in amendments raises questions about potential adverse effects on biota and development of antibiotic resistance in the environment. Hazard risks are largely dictated by sorption-desorption and diffusion behavior in amendments, so these processes were evaluated from sorption-desorption equilibrium isotherm and diffusion cell experiments with four types amendments (biosolids, poultry manure, wood chip litter, and rice hull litter) at three temperatures (8 °C, 20 °C and 32 °C). Linear sorption-desorption equilibrium distribution constants (Kd) in native amendments ranged between 124-2418 L kg -1 . TET sorption was significantly increased after treatment with alum, and there was a strong exponential relationship between Kd and the concentration of bound Al 3+ in amendments (R 2  = 0.94), which indicated that amendments contained functional groups capable of chelating Al 3+ and forming metal bridges with TET. Effective diffusion coefficients of TET in amendments ranged between 0.1 and 5.2 × 10 -6  cm 2  s -1 , which were positively related to temperature and inversely related to Kd by a multiple regression model (R 2  = 0.86). Treatment of organic amendments with alum greatly increased Kd, would decrease D s , and so would greatly reduce hazard risks of applying these organic amendments with this antibiotic to soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Development of phosphate rock integrated with iron amendment for simultaneous immobilization of Zn and Cr(VI) in an electroplating contaminated soil.

    PubMed

    Zhao, Ling; Ding, Zhenliang; Sima, Jingke; Xu, Xiaoyun; Cao, Xinde

    2017-09-01

    This study aims to develop an amendment for simultaneous immobilization of Zn and Cr(VI) in an abandoned electroplating contaminated soil. Nature phosphate rock was first activated with oxalic acid (O-PR) and then combined with FeSO 4 or zero-valent iron (ZVI) for immobilization of Zn and Cr(VI) from aqueous solutions. Finally, the optimized approach showing the highest immobilization ability in solution was applied in an electroplating contaminated soil. The O-PR combined with FeSO 4 was more effective in simultaneously removing Zn and Cr(VI) than the O-PR integrated with ZVI within the tested solution pH range of 5.5-8.5. Both O-PR with FeSO 4 and with ZVI removed over 95% of Zn from the solution; however, only 42-46% of Cr(VI) was immobilized by O-PR with ZVI, while O-PR with FeSO 4 almost precipitated all Cr(VI). Moreover, there were 75-95% Zn and 95-100% Cr(VI) remaining in the exhausted O-PR with FeSO 4 solid after toxicity characteristic leaching test (TCLP) while the exhausted O-PR with ZVI solid only retained 44-83% Zn and 32-72% Cr(VI). Zinc was immobilized mainly via formation of insoluble Fe-Zn phosphate co-precipitates, while iron-induced reduction of Cr(VI) into stable Cr(OH) 3 or Cr x Fe (1-x) (OH) 3 was responsible for Cr(VI) immobilization. Application of the O-PR integrated with FeSO 4 in the electroplating contaminated soil rapidly reduced the TCLP extractable Zn and Cr(VI) to below the standard limits, with decrease by 50% and 94%, respectively. This study revealed that combination of oxalic acid activated phosphate rock with FeSO 4 could be an effective amendment for remediation of Zn and Cr(VI) contaminated soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. [Effect of lignite humic acid on soil ammonia oxidizing archaea community].

    PubMed

    Dong, Lianhua; Li, Baozhen; Yuan, Hongli; Scow, Kate M

    2010-06-01

    To illuminate the impact of humic acid (HA) on soil ammonia oxidizing archaea and then reveal the effect of HA on soil nitrogen cycle. Two humic acids (cHA and bHA) were added into the soil amended with urea. Community changes of ammonia oxidizing archaea (AOA) and total archaea were studied with terminal restricted fragment length polymorphism (T-RFLP) and real time PCR in the microcosm experiment. We found that the AOA population size increased significantly and AOA community changed greatly in the urea only treatment. However, HA could inhibit the increase of AOA population, moreover, HA could buffer the change in AOA community showed by canonical correspondence analysis (CCA) result. On the other hand, the total archaeal population decreased significantly in the urea only treatment, but stabilized in the urea with HA treatments, which indicated HA could eliminate the toxicity of urea to total archaea. CCA results showed that incubation time was the most important factor for the total archaeal community, and partial CCA (pCCA, when time as a covariable) result demonstrated that cHA was the most important environmental variable for total archaeal community. These results showed that HA diminished ammonia loss by inhibiting the increase of AOA competing with plant for ammonia, thus HA can increase the urea efficiency.

  9. Relationship between organic matter humification and bioavailability of sludge-borne copper and cadmium during long-term sludge amendment to soil.

    PubMed

    Liu, Hongtao

    2016-10-01

    Recycling of sludge as soil amendment poses certain risk of heavy metals contamination. This study investigated the relationship between organic matter in composted sludge and its heavy metals bioavailability over 7years. Periodic monitoring indicated a gradual increase in organic matter degradation, accompanied by changing degrees of polymerization, i.e., ratio of humic acid (HA)/fulvic acid (FA) coupled with incremental exchangeable fraction of copper (Cu) in sludge, with a growing rate of 74.7%, rather than that in soil. However, cadmium (Cd) in composted sludge exhibited an independent manner. Linear-regression analysis revealed that the total proportion of the Cu active fraction (exchangeable plus carbonate bound) was better correlated with the degree of polymerization (DP) and humification ratio (HR) than the degradation ratio of organic matter. Overall, amount of uptaken Cu was more dependent on the humification degree of organic matter, especially the proportion of HA in humus. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Survival of generic E. coli and surrogate E. coli O157:H7 in manure-amended soils

    USDA-ARS?s Scientific Manuscript database

    Introduction: Recently released U.S. FDA standards state that untreated biological soil amendments must be applied to soil 9 months before produce crop harvest to reduce pathogen contamination risk on produce. Manure and soil type may impact survival of bacterial pathogens. Purpose: Determine survi...

  11. Citric acid- and Tween(®) 80-assisted phytoremediation of a co-contaminated soil: alfalfa (Medicago sativa L.) performance and remediation potential.

    PubMed

    Agnello, A C; Huguenot, D; van Hullebusch, E D; Esposito, G

    2016-05-01

    A pot experiment was designed to assess the phytoremediation potential of alfalfa (Medicago sativa L.) in a co-contaminated (i.e., heavy metals and petroleum hydrocarbons) soil and the influence of citric acid and Tween(®) 80 (polyethylene glycol sorbitan monooleate), applied individually and combined together, for their possible use in chemically assisted phytoremediation. The results showed that alfalfa plants could tolerate and grow in a co-contaminated soil. Over a 90-day experimental time, shoot and root biomass increased and negligible plant mortality occurred. Heavy metals were uptaken by alfalfa to a limited extent, mostly by plant roots, and their concentration in plant tissues were in the following order: Zn > Cu > Pb. Microbial population (alkane-degrading microorganisms) and activity (lipase enzyme) were enhanced in the presence of alfalfa with rhizosphere effects of 9.1 and 1.5, respectively, after 90 days. Soil amendments did not significantly enhance plant metal concentration or total uptake. In contrast, the combination of citric acid and Tween(®) 80 significantly improved alkane-degrading microorganisms (2.4-fold increase) and lipase activity (5.3-fold increase) in the rhizosphere of amended plants, after 30 days of experiment. This evidence supports a favorable response of alfalfa in terms of tolerance to a co-contaminated soil and improvement of rhizosphere microbial number and activity, additionally enhanced by the joint application of citric acid and Tween(®) 80, which could be promising for future phytoremediation applications.

  12. 75 FR 1555 - National Organic Program; Proposed Amendments to the National List of Allowed and Prohibited...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ... use in organic crops soil amendment purposes due to the quick degradation of sulfurous acid, provided...-09-0081; TM-09-04] RIN 0581-AC93 National Organic Program; Proposed Amendments to the National List... the Secretary of Agriculture (Secretary) by the National Organic Standards Board (NOSB) on November 19...

  13. Select geotechnical properties of a lime stabilized expansive soil amended with bagasse ash and coconut shell powder

    NASA Astrophysics Data System (ADS)

    James, Jijo; Pandian, P. Kasinatha

    2018-03-01

    Lime stabilization has been and still is one of the most preferred methods for stabilization of expansive soils. However, in the recent times, utilization of solid waste materials in soil stabilization has gained prominence as an effective means to manage wastes generated from various sources. In this work, an attempt has been made to utilize waste materials from two sources as auxiliary additives to lime in the stabilization of an expansive soil. Bagasse ash (BA), a waste by-product from the sugar industry and Coconut shell powder (CSP), a processed waste obtained from left over coconut shells of oil extraction industry were used as auxiliary additives. An expansive soil obtained from a local field was subjected to chemical, mineral, microstructural and geotechnical characterization in the laboratory and stabilized using 3% lime. The waste materials were subjected to chemical, mineral and microstructural characterization. The stabilization process was amended with four different contents viz. 0.25%, 0.5%, 1% and 2% of BA and CSP separately and the effect of the amendment was studied on the unconfined compressive strength (UCS), plasticity, swell-shrink and microstructural characteristics of the expansive soil. The results of the study indicated that BA amendment of lime stabilization performed better than CSP in improving the UCS, plasticity, swell-shrink and microstructure of the lime stabilized expansive soil.

  14. Soil amendments improve microbial ecology parameters of "topsoil inoculum" used in post-mining restoration

    NASA Astrophysics Data System (ADS)

    Kumaresan, Deepak; Munoz-Rojas, Miriam; Moreira-Grez, Benjamin; Kariman, Khalil; Whiteley, Andrew

    2017-04-01

    Mine operations generate substantial volumes of waste substrates, which are crushed and/or chemically treated waste rock from which ores are extracted. Establishment of rehabilitated landforms using post-mining substrates (i.e. waste rocks, tailings) that typically exhibit extreme conditions (such as high pH, nutrient deficiency, excessive salinity and metal toxicity) can be a major environmental problem and a critical issue during mine closure operations. More importantly, mine sites are located predominantly in arid or semi-arid lands where our understanding of basic ecosystem processes and microbial interactions with native plants (e.g. Eucalyptus spp., Acacia spp., Grevillea spp. in Western Australia) are limited. Despite the wide acknowledgement on the impact of microbial functional diversity on overall soil and plant health, no detailed attention has been paid to understand the role of belowground microbial functional diversity in the context of mine rehabilitation strategies. In this research, we investigated the role of nitrogen-based and microbial consortia amendments on improving the microbial ecology parameters of "topsoil inoculum" and subsequently its cascading effect on seedling establishment and plant morphology of Acacia ancistrocarpa, a legume native to the Pilbara and other regions of Western Australia and commonly used in arid zone restoration. The study was conducted under controlled environmental conditions in potted plants using topsoil retrieved from previously stockpiled material as growth media. A morphological assessment was undertaken to measure shoot length, shoot weight, root length, root area and root weight. Soil chemical properties, e.g. carbon, nitrogen and trace metals concentrations were determined Microbial activity was measured with the 1-day CO2 test, which determines soil microbial respiration rate based on the measurement of the CO2 burst produced after moistening dry soil (Muñoz-Rojas et al., 2016). Bacterial and archaeal

  15. Influence of Flue Gas Desulfurization Gypsum Amendments on Heavy Metal Distribution in Reclaimed Sodic Soils.

    PubMed

    Chen, Qun; Wang, Shujuan; Li, Yan; Zhang, Ning; Zhao, Bo; Zhuo, Yuqun; Chen, Changhe

    2015-06-01

    Although flue gas desulfurization (FGD) gypsum has become an effective soil amendment for sodic soil reclamation, it carries extra heavy metal contamination into the soil environment. The fate of heavy metals introduced by FGD gypsum in sodic or saline-alkali soils is still unclear. This work aims to investigate the effects of FGD gypsum addition on the heavy metal distributions in a sodic soil. Original soil samples were collected from typical sodic land in north China. Soil column leaching tests were conducted to investigate the influence of FGD gypsum addition on the soil properties, especially on distribution profiles of the heavy metals (Pb, Cd, Cr, As, and Hg) in the soil layers. Results showed that pH, electrical conductivity, and exchangeable sodium percentage in amended soils were significantly reduced from 10.2 to 8.46, 1.8 to 0.2 dS/m, and 18.14% to 1.28%, respectively. As and Hg concentrations in the soils were found to be positively correlated with FGD gypsum added. The amount of Hg in the leachate was positively correlated with FGD gypsum application ratio, whereas a negative correlation was observed between the Pb concentration in the leachate and the FGD gypsum ratio. Results revealed that heavy metal concentrations in soils complied well with Environmental Quality Standard for Soils in China (GB15618-1995). This work helps to understand the fate of FGD gypsum-introduced heavy metals in sodic soils and provides a baseline for further environmental risk assessment associated with applying FGD gypsum for sodic soil remediation.

  16. Influence of Flue Gas Desulfurization Gypsum Amendments on Heavy Metal Distribution in Reclaimed Sodic Soils

    PubMed Central

    Chen, Qun; Wang, Shujuan; Li, Yan; Zhang, Ning; Zhao, Bo; Zhuo, Yuqun; Chen, Changhe

    2015-01-01

    Abstract Although flue gas desulfurization (FGD) gypsum has become an effective soil amendment for sodic soil reclamation, it carries extra heavy metal contamination into the soil environment. The fate of heavy metals introduced by FGD gypsum in sodic or saline–alkali soils is still unclear. This work aims to investigate the effects of FGD gypsum addition on the heavy metal distributions in a sodic soil. Original soil samples were collected from typical sodic land in north China. Soil column leaching tests were conducted to investigate the influence of FGD gypsum addition on the soil properties, especially on distribution profiles of the heavy metals (Pb, Cd, Cr, As, and Hg) in the soil layers. Results showed that pH, electrical conductivity, and exchangeable sodium percentage in amended soils were significantly reduced from 10.2 to 8.46, 1.8 to 0.2 dS/m, and 18.14% to 1.28%, respectively. As and Hg concentrations in the soils were found to be positively correlated with FGD gypsum added. The amount of Hg in the leachate was positively correlated with FGD gypsum application ratio, whereas a negative correlation was observed between the Pb concentration in the leachate and the FGD gypsum ratio. Results revealed that heavy metal concentrations in soils complied well with Environmental Quality Standard for Soils in China (GB15618-1995). This work helps to understand the fate of FGD gypsum-introduced heavy metals in sodic soils and provides a baseline for further environmental risk assessment associated with applying FGD gypsum for sodic soil remediation. PMID:26064038

  17. Impact of low molecular weight organic acids and dissolved organic matter on sorption and mobility of isoproturon in two soils.

    PubMed

    Ding, Qing; Wu, Hai Lang; Xu, Yun; Guo, Li Juan; Liu, Kai; Gao, Hui Min; Yang, Hong

    2011-06-15

    Isoproturon is a selective herbicide belonging to the phenylurea family and widely used for pre- and post-emergence control of annual weeds. Soil amendments (e.g. organic compounds or dissolved organic matter) may affect environmental behavior and bioavailability of pesticides. However, whether the physiochemical process of isoproturon in soils is affected by organic amendments and how it is affected in different soil types are unknown. To evaluate the impact of low molecular weight organic acids (LMWOA) and dissolved organic matter (DOM) on sorption/desorption and mobility of isoproturon in soils, comprehensive analyses were performed using two distinct soil types (Eutric gleysols and Hap udic cambisols). Our analysis revealed that adsorption of isoproturon in Eutric gleysols was depressed, and desorption and mobility of isoproturon were promoted in the presence of DOM and LMWOA. However, the opposite result was observed with Hap udic cambisols, suggesting that the soil type affected predominantly the physiochemical process. We also characterized differential components of the soils using three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy and Fourier transform infrared (FT-IR) spectroscopy and show that the two soils displayed different intensity of absorption bands for several functional groups. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Organic amendments derived from a pharmaceutical by-product: benefits and risks

    NASA Astrophysics Data System (ADS)

    Gigliotti, Giovanni; Cucina, Mirko; Zadra, Claudia; Pezzolla, Daniela; Sordi, Simone; Carla Marcotullio, Maria; Curini, Massimo

    2015-04-01

    The application of organic amendments to soils, such as sewage sludge, anaerobic digestate and compost is considered a tool for improving soil fertility and enhancing C stocks. The addition of these different organic materials allows a good supply of nutrients for plants but also contributes to C sequestration, affects the microbial activity and the transformation of soil organic matter (SOM). Moreover, the addition of organic amendment has gained importance as a source of CO2 emissions and then as a cause of the "Global Warming". Therefore, it is important to investigate the factors controlling the SOM mineralization in order to improve the soil C sequestration and decreasing at the same time CO2 emissions. Moreover, the quality of organic matter added to the soil will play an important role in these dynamics. Based on these considerations, the aim of the present work was to investigate the effect of the application to an arable soil of different organic materials derived from a pharmaceutical by-product which results from the fermentative biomass after the separation of the lipopolypeptidic antibiotic produced. A microcosm soil experiment was carried out using three different materials: a sewage sludge derived from the stabilization process of the by-product, a digestate obtained from the anaerobic treatment of the by-product and a compost produced by the aerobic treatment of the same digestate. To achieve this aim, the short-term variations of CO2 emissions, enzymatic soil activities (Dehydrogenase total activity and Fluoresceine diacetate hydrolysis), SOM quantity and quality were studied. In addition, process-related residues of antibiotic and decanoic acid (a precursor added during the fermentation) were analyzed on the organic materials to assess their possible presence. Through these analyses it was possible to state that the application to the soil of sewage sludge and anaerobic digestate may have a strong influence on the short-term variations of the

  19. Changes in available nitrogen and nematode abundance in response to Brassica seed meal amendment of orchard soil

    USDA-ARS?s Scientific Manuscript database

    Brassica tissues are often promoted as a soil amendment to meet various management objectives, particularly in organic production systems. To predict the efficacy of brassicaceae seed meal amendments as either biofumigants or organic fertilizers, a better understanding of the impacts of seed meal am...

  20. Effects of straw and biochar amendments on aggregate stability, soil organic carbon, and enzyme activities in the Loess Plateau, China.

    PubMed

    Zhang, Man; Cheng, Gong; Feng, Hao; Sun, Benhua; Zhao, Ying; Chen, Haixin; Chen, Jing; Dyck, Miles; Wang, Xudong; Zhang, Jianguo; Zhang, Afeng

    2017-04-01

    Soil from the Loess Plateau of China is typically low in organic carbon and generally has poor aggregate stability. Application of organic amendments to these soils could help to increase and sustain soil organic matter levels and thus to enhance soil aggregate stability. A field experiment was carried out to evaluate the effect of the application of wheat straw and wheat straw-derived biochar (pyrolyzed at 350-550 °C) amendments on soil aggregate stability, soil organic carbon (SOC), and enzyme activities in a representative Chinese Loess soil during summer maize and winter wheat growing season from 2013 to 2015. Five treatments were set up as follows: no fertilization (CK), application of inorganic fertilizer (N), wheat straw applied at 8 t ha -1 with inorganic fertilizer (S8), and wheat straw-derived biochar applied at 8 t ha -1 (B8) and 16 t ha -1 (B16) with inorganic fertilizer, respectively. Compared to the N treatment, straw and straw-derived biochar amendments significantly increased SOC (by 33.7-79.6%), microbial biomass carbon (by 18.9-46.5%), and microbial biomass nitrogen (by 8.3-38.2%), while total nitrogen (TN) only increased significantly in the B16 plot (by 24.1%). The 8 t ha -1 straw and biochar applications had no significant effects on soil aggregation, but a significant increase in soil macro-aggregates (>2 mm) (by 105.8%) was observed in the B16 treatment. The concentrations of aggregate-associated SOC increased by 40.4-105.8% in macro-aggregates (>2 mm) under straw and biochar amendments relative to the N treatment. No significant differences in invertase and alkaline phosphatase activity were detected among different treatments. However, urease activity was greater in the biochar treatment than the straw treatment, indicating that biochar amendment improved the transformation of nitrogen in the soil. The carbon pool index and carbon management index were increased with straw and biochar amendments, especially in the B16 treatment

  1. Effect of Lupinus albus L. root activities on As and Cu mobility after addition of iron-based soil amendments.

    PubMed

    Fresno, Teresa; Peñalosa, Jesús M; Santner, Jakob; Puschenreiter, Markus; Moreno-Jiménez, Eduardo

    2017-09-01

    Arsenic and Cu mobility was investigated in the rhizosphere of Lupinus albus L. grown in an iron-amended contaminated soil. White lupin was grown in rhizobags in contaminated soil either left untreated or amended with iron sulphate plus lime (Fe + lime) or biochar (Fe + BC). Porewater was monitored in rhizosphere and bulk soil throughout the experiment and the extractable fraction of several elements and As and Cu plant uptake was analysed after 48 days. The distribution of As, Cu, P and Fe in the lupin rhizosphere was evaluated with chemical images obtained by laser ablation-ICP-MS analysis of diffusive gradients in thin films (DGT) gels. The treatments effectively reduced the soluble and extractable As and Cu fractions in the bulk soil, but they did not affect plant uptake. In all cases, soluble As was slightly enhanced in the rhizosphere. This difference was more pronounced in the Fe + lime-treated rhizosphere soil, where an increase of pH as well as extractable As and Fe concentrations were also observed. Chemical imaging of the lupin rhizosphere also showed slightly higher As- and Fe-DGT fluxes around lupin roots grown in the non-amended soil. Our findings indicate As and Fe co-solubilisation by lupin root exudates, likely as a response to P deficiency. Arsenic mobilisation occurred only in the rhizosphere and was not decreased by the amendments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Yield, quality, and concentration of seven heavy metals in cabbage and broccoli grown in sewage sludge and chicken manure amended soil.

    PubMed

    Antonious, George F; Kochhar, Tejinder S; Coolong, Timothy

    2012-01-01

    The mobility of heavy metals from soil into the food chain and their subsequent bioaccumulation has increased the attention they receive as major environmental pollutants. The objectives of this investigation were to: i) study the impact of mixing native agricultural soil with municipal sewage sludge (SS) or chicken manure (CM) on yield and quality of cabbage and broccoli, ii) quantify the concentration of seven heavy metals (Cd, Cr, Mo, Cu, Zn, Pb, and Ni) in soil amended with SS or CM, and iii) determine bioavailability of heavy metals to cabbage leaves and broccoli heads at harvest. Analysis of the two soil amendments used in this investigation indicated that Cr, Ni, Cu, Zn, Mo, Cd, Pb, and organic matter content were significantly greater (P < 0.05) in premixed sewage sludge than premixed chicken manure. Total cabbage and broccoli yields obtained from SS and CM mixed soil were both greater than those obtained from no-mulch (bare) soil. Concentration of Ni in cabbage leaves of plants grown in soil amended with CM was low compared to plants grown in no-mulch soil. No significant differences were found in Cd and Pb accumulation between cabbage and broccoli. Concentrations of Ni, Cu, Zn, and Mo were greater in broccoli than cabbage. Total metals and plant available metals were also determined in the native and amended soils. Results indicated that the concentration of heavy metals in soils did not necessary reflect metals available to plants. Regardless of soil amendments, the overall bioaccumulation factor (BAF) of seven heavy metals in cabbage leaves and broccoli heads revealed that cabbage and broccoli were poor accumulators of Cr, Ni, Cu, Cd, and Pb (BAF <1), while BAF values were >1 for Zn and Mo. Elevated Ni and Mo bioaccumulation factor (BAF >1) of cabbage grown in chicken manure mixed soil is a characteristic that would be less favorable when cabbage is grown on sites having high concentrations of these two metals.

  3. Effectiveness of T. harzianum and Humate Amendment in Soil Salinity Restoration

    NASA Astrophysics Data System (ADS)

    Apostolakis, Antonios; Daliakopoulos, Ioannis; Tsanis, Ioannis

    2017-04-01

    Soil salinity is a major soil degradation threat, especially for the water stressed parts of the Mediterranean region, where it hinders soil fertility and thus agricultural productivity. Soil salinity management can be complex and expensive, often resorting to the use of chemical amendments thus risking soil and aquifer pollution. This study quantifies the beneficial effects of (a) a commercial strain of the beneficial fungus Trichoderma harzianum (TH), and (b) a commercial humate fertilizer enhancer (HFE) approved for organic farming, against soil salinization. The treatments are tested in the context of a Solanum lycopersicum (tomato) greenhouse simulation of the cultivation conditions typical for the semi-arid coastal Timpaki basin in south-central Crete. 20 vigorous 20-day-old Solanum lycopersicum L. cv Elpida seedlings are treated either with TH or HFE, using soil substrates and irrigation treatments of two degradation states. 20 additional plants serve either as controls or guard rows. All plants are transplanted into 35 L pots under greenhouse conditions. Preliminary analysis of soil salinity and crop yield indicators suggest that both treatments are beneficial for the soil-plant system, each to a different extent depending on initial soil conditions.

  4. Uptake of perfluoroalkyl acids into edible crops via land ...

    EPA Pesticide Factsheets

    The presence of perfluoroalkyl acids (PFAAs) in biosolids destined for use in agriculture has raised concerns about their potential to enter the terrestrial food chain via bioaccumulation in edible plants. Uptake of PFAAs by greenhouse lettuce ( Lactuca sativa) and tomato (Lycopersicon lycopersicum ) grown in an industrially impacted biosolids-amended soil, a municipal biosolids-amended soil, and a control soil was measured. Bioaccumulation factors (BAFs) were calculated for the edible portions of both lettuce and tomato. Dry weight concentrations observed in lettuce grown in a soil amended (biosolids:soil dry weight ratio of 1:10) with PFAA industrially contaminated biosolids were up to 266 and 236 ng/g for perfluorobutanoic acid (PFBA) and perfluoropentanoic acid (PFPeA), respectively, and reached 56 and 211 ng/g for PFBA and PFPeA in tomato, respectively. BAFs for many PFAAs were well above unity, with PFBA having the highest BAF in lettuce (56.8) and PFPeA the highest in tomato (17.1). In addition, the BAFs for PFAAs in greenhouse lettuce decreased approximately 0.3 log units per CF2 group. A limited-scale field study was conducted to verify greenhouse findings. The greatest accumulation was seen for PFBA and PFPeA in both field-grown lettuce and tomato; BAFs for PFBA were highest in both crops. PFAA levels measured in lettuce and tomato grown in field soil amended with only a single application of biosolids (at an agronomic rate for nitrogen) were predomina

  5. Manure-amended soil characteristics affecting the survival of E. coli O157:H7 in 36 Dutch soils.

    PubMed

    Franz, Eelco; Semenov, Alexander V; Termorshuizen, Aad J; de Vos, O J; Bokhorst, Jan G; van Bruggen, Ariena H C

    2008-02-01

    The recent increase in foodborne disease associated with the consumption of fresh vegetables stresses the importance of the development of intervention strategies that minimize the risk of preharvest contamination. To identify risk factors for Escherichia coli O157:H7 persistence in soil, we studied the survival of a Shiga-toxin-deficient mutant in a set of 36 Dutch arable manure-amended soils (organic/conventional, sand/loam) and measured an array of biotic and abiotic manure-amended soil characteristics. The Weibull model, which is the cumulative form of the underlying distribution of individual inactivation kinetics, proved to be a suitable model for describing the decline of E. coli O157:H7. The survival curves generally showed a concave curvature, indicating changes in biological stress over time. The calculated time to reach the detection limit ttd ranged from 54 to 105 days, and the variability followed a logistic distribution. Due to large variation among soils of each management type, no differences were observed between organic and conventional soils. Although the initial decline was faster in sandy soils, no significant differences were observed in ttd between both sandy and loamy soils. With sandy, loamy and conventional soils, the variation in ttd was best explained by the level of dissolved organic carbon per unit biomass carbon DOC/biomC, with prolonged survival at increasing DOC/biomC. With organic soils, the variation in ttd was best explained by the level of dissolved organic nitrogen (positive relation) and the microbial species diversity as determined by denaturing gradient gel electrophoresis (negative relation). Survival increased with a field history of low-quality manure (artificial fertilizer and slurry) compared with high-quality manure application (farmyard manure and compost). We conclude that E. coli O157:H7 populations decline faster under more oligotrophic soil conditions, which can be achieved by the use of organic fertilizer with a

  6. Assessing the influence of compost and biochar amendments on the mobility and toxicity of metals and arsenic in a naturally contaminated mine soil.

    PubMed

    Beesley, Luke; Inneh, Onyeka S; Norton, Gareth J; Moreno-Jimenez, Eduardo; Pardo, Tania; Clemente, Rafael; Dawson, Julian J C

    2014-03-01

    Amending contaminated soils with organic wastes can influence trace element mobility and toxicity. Soluble concentrations of metals and arsenic were measured in pore water and aqueous soil extracts following the amendment of a heavily contaminated mine soil with compost and biochar (10% v:v) in a pot experiment. Speciation modelling and toxicity assays (Vibrio fischeri luminescence inhibition and Lolium perenne germination) were performed to discriminate mechanisms controlling metal mobility and assess toxicity risk thereafter. Biochar reduced free metal concentrations furthest but dissolved organic carbon primarily controlled metal mobility after compost amendment. Individually, both amendments induced considerable solubilisation of arsenic to pore water (>2500 μg l(-1)) related to pH and soluble phosphate but combining amendments most effectively reduced toxicity due to simultaneous reductions in extractable metals and increases in soluble nutrients (P). Thus the measure-monitor-model approach taken determined that combining the amendments was most effective at mitigating attendant toxicity risk. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Does thermal carbonization (Biochar) of organic material increase more merits for their amendments of sandy soil?

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Xu, G.; Sun, J. N.; Shao, H. B.

    2014-02-01

    Organic materials (e.g. furfural residue) are generally believed to improve the physical and chemical properties of the soils with low fertility. Recently, biochar have been received more attention as a possible measure to improve the carbon balance and improve soil quality in some degraded soils. However, little is known about their different amelioration of a sandy saline soil. In this study, 56d incubation experiment was conducted to evaluate the influence of furfural and its biochar on the properties of saline soil. The results showed that both furfural and biochar greatly reduced pH, increased soil organic carbon (SOC) content and cation exchange capacity (CEC), and enhanced the available phosphorus (P) in the soil. Furfural is more efficient than biochar in reducing pH: 5% furfural lowered the soil pH by 0.5-0.8 (soil pH: 8.3-8.6), while 5% biochar decreased by 0.25-0.4 due to the loss of acidity in pyrolysis process. With respect to available P, 5% of the furfural addition increased available P content by 4-6 times in comparison to 2-5 times with biochar application. In reducing soil exchangeable sodium percentage (ESP), biochar is slightly superior to furfural because soil ESP reduced by 51% and 43% with 5% furfural and 5% biochar addition at the end of incubation. In addition, no significant differences were observed between furfural and biochar about their capacity to retain N, P in leaching solution and to increase CEC in soil. These facts may be caused by the relatively short incubation time. In general, furfural and biochar have different amendments depending on soil properties: furfural was more effectively to decrease pH and to increase available P, whereas biochar played a more important role in increasing SOC and reducing ESP of saline soil.

  8. THE PHYTOAVAILABILITY OF CADMIUM TO LETTUCE IN LONG-TERM BIOSOLIDS-AMENDED SOILS

    EPA Science Inventory

    A field study was conducted to assess the phytoavailability of Cd in long-term biosolids-amended field plots managed at high and low pH. The experiment, established 13-15 yr prior to the present cropping, on a Christiana fine sandy loam soil (a clayey, kaolinitic, mesic Typic Pa...

  9. Modeling Cd and Cu mobility in soils amended by long-term urban waste compost applications

    NASA Astrophysics Data System (ADS)

    Filipović, Vilim; Cambier, Philippe; Matijević, Lana; Coquet, Yves; Pot, Valérie; Houot, Sabine; Benoit, Pierre

    2016-04-01

    Urban waste compost application to soil is an effective way for organic waste disposal and at the same time may have a positive effect on various soil rhizosphere processes. However, long term applications of organic waste amendments may lead to a noteworthy accumulation of micropollutants in soil. The long-term field experiment QualiAgro, an INRA-Veolia partnership (https://www6.inra.fr/qualiagro_eng/), has been conducted since 1998 with the objectives to characterize the agronomic value of urban composts and the environmental impacts of their application. Numerical modeling was performed using HYDRUS-2D to estimate the movement of Cd and Cu from compost incroporation in the tilled layer. Experimental plots regularly amended with co-compost of sewage sludge and green wastes (SGW), or a municipal solid waste compost (MSW) have been compared to control plot without any organic amendment (CONT). Field site was equipped with wicks lysimeters, TDR probes and tensiometers in order to determine water balance and trace metal concentrations during a 6 years' time period (2004-2010). In the tilled layer different structures (Δ - compacted clods, Γ - macroporous zone, IF - interfurrows, PP - plough pan) corresponding to the tillage and compost incorporation were delimited and reproduced in a 2-D model. The increase of Cd and Cu concentrations due to each compost addition was assumed to be located in IFs for further modeling. Four compost additions were performed during 2004-2010 period which increased the Cd and Cu concentrations in the IF zones considerably. After successful model description of water flow in highly heterogeneous soil profiles, Cd and Cu were added into the model and their fate was simulated during the same time period. Two approaches were followed to estimate plausible trace metals sorption coefficients (Kd), both while assuming equilibrium between dissolved and EDTA-extractable metals. The first approach was based on Kd estimated from ratios between

  10. Importance of soil amendments: survival of bacterial pathogens in manure and compost used as organic fertizliers

    USDA-ARS?s Scientific Manuscript database

    Biological soil amendments (BSA’s) like manure and compost are frequently used as organic fertilizers to soils to improve its physical and chemical properties. However, BSAs have been known to be a reservoir for enteric bacterial pathogens like enterohemorrhagic E. coli, Salmonella spp, and Listeri...

  11. Evaluation of the effectiveness of sepiolite, bentonite, and phosphate amendments on the stabilization remediation of cadmium-contaminated soils.

    PubMed

    Sun, Yuebing; Sun, Guohong; Xu, Yingming; Liu, Weitao; Liang, Xuefeng; Wang, Lin

    2016-01-15

    A pot trial was conducted to assess the effectiveness of sepiolite, bentonite, and phosphate on the immobilization remediation of cadmium (Cd)-contaminated soils using a set of variables, namely, physiological traits, sequential extraction procedure, plant growth and Cd concentration, and soil enzymatic activities and microbial population. Results showed that superoxide dismutase and peroxidase activities in the leaves of Oryza sativa L. and catalase activities in soils were stimulated after applying the amendments. However, soluble protein contents in leaves and urease and invertase activities in soils were reduced from 7.1% to 31.7%, 1.0%-23.3%, and 21.1%-62.5%, respectively, compared with the control. Results of the sequence extraction procedures revealed that the exchangeable fraction of Cd in soils was mostly converted into carbonated-associated forms. The water soluble plus exchangeable fraction (SE) of Cd in soil decreased when treated with single and compound materials of sepiolite, bentonite and phosphate, which resulted in 13.2%-69.2% reduction compared with that of CK (control test). The amendments led to decreased Cd concentrations in roots, stems, leaves, brown rice, and rice hull by 16.2%-54.5%, 16.6%-42.8%, 19.6%-59.6%, 5.0%-68.2%, and 6.2%-20.4%, respectively. Higher bacterial and actinomycete amount indicated that remediation measures improved soil environmental quality. Composite amendments could be more efficiently used for the stabilization remediation of Cd contaminated soils with low Cd uptake and translocation in the plants and available contents of Cd in soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effect of two different composts on soil quality and on the growth of various plant species in a polymetallic acidic mine soil.

    PubMed

    Rossini-Oliva, S; Mingorance, M D; Peña, A

    2017-02-01

    The effect of the addition (0-10%) of two types of sewage sludge composts (composted sewage sludge [CS] and sewage sludge co-composted with olive prune wastes [CSO]) on a polymetallic acidic soil from the Riotinto mining area was evaluated by i) a soil incubation experiment and ii) a greenhouse pot experiment using tomato (Solanum lycopersicum Mill.), ryegrass (Lolium perenne L.) and ahipa (Pachyrhizus ahipa (Wedd.) Parodi). Compost addition improved the soil organic carbon content, increased the pH and the electrical conductivity and enhanced enzyme activities and soil respiration, more for CSO than for CS. Plant growth was generally enhanced after compost addition, but not proportionally to the dose. Foliar concentrations of some hazardous elements (As, Cr, Fe) in tomato growing in non-amended soil were above the thresholds, questioning the adequacy of using this plant species. However, leaf concentrations of essential and potentially toxic elements (Fe, As, Cr and Pb) in tomato and/or ryegrass were reduced after the amendment with both composts, generally more for CSO than for CS. Conversely, foliar concentrations in ahipa, a plant species which is able to grow without the need of compost addition, were safe except for As and were only slightly affected by compost addition. This plant species would be a suitable candidate due to its low requirements and due to the limited element translocation to the leaves. Concerning the composts, amelioration of plant and soil properties was better accomplished when using CSO, a compost of sewage sludge and plant remains, than when using CS, which only contained the sludge. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Enhancement of Cd phytoextraction by hyperaccumulator Sedum alfredii using electrical field and organic amendments.

    PubMed

    Xiao, Wendan; Li, Dan; Ye, Xuezhu; Xu, Haizhou; Yao, Guihua; Wang, Jingwen; Zhang, Qi; Hu, Jing; Gao, Na

    2017-02-01

    The combined use of organic amendment-assisted phytoextraction and electrokinetic remediation to decontaminate Cd-polluted soil was demonstrated in a laboratory-scale experiment. The plant species selected was the hyperaccumulator Sedum alfredii. Prior to the pot experiment, the loamy soil was treated with 15 g kg -1 of pig manure compost, 10 g kg -1 of humic acid, or 5 mmol kg -1 of EDTA, and untreated soil without application of any amendment was the control. Two conditions were applied to each treatment: no voltage (without an electrical field) and a direct current (DC) electrical field (1 V cm -1 with switching polarity every day). Results indicated that Cd concentrations in S. alfredii were significantly (p < 0.05) increased by application of the electrical field and soil amendments (pig manure compost, humic acid, and EDTA). By switching the polarity of the DC electrical field, significant pH variation from anode to cathode can be avoided, and no significant impact was observed on shoot biomass production. Electrical field application increased DTPA-extractable Cd in soils and the Cd accumulation in shoots by 6.06-15.64 and 24.53-52.31%, respectively. The addition of pig manure compost and humic acid enhanced shoot Cd accumulation by 1.54- to 1.92- and 1.38- to 1.64-fold because of their simultaneous enhancement of Cd concentration in shoots and biomass production. However, no enhancement of Cd accumulation was found in the EDTA treatment, which can be ascribed to the inhibition of plant growth caused by EDTA. In conclusion, pig manure compost or humic acid addition in combination with the application of a switched-polarity DC electrical field could significantly enhance Cd phytoextraction by hyperaccumulator S. alfredii.

  14. Microscopic and spectroscopic characterization of humic substances from a compost amended copper contaminated soil: main features and their potential effects on Cu immobilization.

    PubMed

    Medina, Jorge; Monreal, Carlos; Chabot, Denise; Meier, Sebastián; González, María Eugenia; Morales, Esteban; Parillo, Rita; Borie, Fernando; Cornejo, Pablo

    2017-06-01

    We characterized humic substances (HS) extracted from a Cu-contaminated soil without compost addition (C) or amended with a wheat straw-based compost (WSC) (H1), co-composted with Fe 2 O 3 (H2), or co-composted with an allophane-rich soil (H3). Extracted HS were characterized under electron microscopy (SEM/TEM), energy-dispersive X-ray (X-EDS), and Fourier transform infrared (FTIR) spectroscopy. In addition, HS extracted from WSC (H4) were characterized at pH 4.0 and 8.0 with descriptive purposes. At pH 4.0, globular structures of H4 were observed, some of them aggregating within a large network. Contrariwise, at pH 8.0, long tubular and disaggregated structures prevailed. TEM microscopy suggests organo-mineral interactions at scales of 1 to 200 nm with iron oxide nanoparticles. HS extracted from soil-compost incubations showed interactions at nanoscale with minerals and crystal compounds into the organic matrix of HS. Bands associated to acidic functional groups of HS may suggest potential sorption interactions with transition metals. We conclude that metal ions and pH have an important role controlling the morphology and configuration of HS from WSC. Characterization of H4 extracted from WSC showed that physicochemical protection of HS could be present in composting systems treated with inorganic materials. Finally, the humified fractions obtained from compost-amended soils may have an important effect on metal-retention, supporting their potential use in metal-contaminated soils.

  15. Organic and inorganic amendments affect soil concentration and accumulation of cadmium and lead in wheat in calcareous alkaline soils

    USDA-ARS?s Scientific Manuscript database

    Irrigation with untreated effluent in periurban agriculture could result in accumulation and bioconcentrations of cadmium (Cd) and lead (Pb). Different amendments were used to investigate their effect on availability, concentration, and uptake of metals by wheat in texturally different soils. Crop w...

  16. Soil amendment affects Cd uptake by wheat - are we underestimating the risks from chloride inputs?

    PubMed

    Dahlin, A Sigrun; Eriksson, Jan; Campbell, Colin D; Öborn, Ingrid

    2016-06-01

    Many parts of the world are investigating the efficacy of recycling nutrient resources to agriculture from different industry and domestic sectors as part of a more circular economy. The complex nature of recycled products as soil amendments coupled to the large diversity of soil types and their inherent properties make it difficult to optimize the benefits and minimize the risks from potentially toxic elements often present in recycled materials. Here we investigated how wheat grain cadmium (Cd) concentration was affected by soil amendments, namely human urine and biogas digestate compared to traditional farm manures and mineral fertilizers. We show that Cl(-) inadvertently added to soils with e.g. urine or biogas digestate strongly increased crop Cd concentrations, largely by mobilizing inherent soil Cd. This resulted in wheat grain Cd levels that could result in exceeding recommended WHO limits for dietary intake. This was evident even in soils with low inherent Cd content and when Cd inputs were low. The future of a circular economy that helps to underpin global food security needs to ensure that the effects of applying complex materials to different types of agricultural land are fully understood and do not jeopardize food safety. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. A proposed NRCS conservation practice standard: Amending soil properties with gypsiferous products

    USDA-ARS?s Scientific Manuscript database

    This paper will discuss the proposed new NRCS conservation practice standard regarding the use of gypsiferous products in agriculture. Gypsiferous products include gypsum (CaSO4 .2H2O), has been used as an agricultural soil amendment for over 250 years as a soluble source of calcium and sulfur for ...

  18. In Situ Fixation of Metal(loid)s in Contaminated Soils: A ...

    EPA Pesticide Factsheets

    This study aimed to assess and compare the in vitro and in vivo bioaccessibility/bioavailability of As and Pb in a mining contaminated soil (As 2267 mg kg-1, Pb 1126 mg kg-1), after the addition of conventional (phosphoric acid), opportunistic [water treatment residues (WTRs)], and engineered [nano- and microscale zero valent iron (ZVI)] amendments. Phosphoric acid was the only amendment that could significantly decrease Pb bioaccessibility with respect to untreated soil (41 and 47% in the gastric phase and 2.1 and 8.1% in the intestinal phases, respectively), giving treatment effect ratios (TERs, the bioaccessibility in the amended soil divided by the bioaccessibility in the untreated soil) of 0.25 and 0.87 in the gastric and intestinal phase, respectively. The in vivo bioavailability of Pb decreased in the phosphate treatment relative to the untreated soil (6 and 24%, respectively), and also in the Fe WTR 2% (12%) and nZVI-2 (13%) treatments. The ZVI amendments caused a decrease in As bioaccessibility, with the greatest decrease in the nZVI2-treated soil (TERs of 0.59 and 0.64 in the gastric and intestinal phases, respectively). Arsenic X-ray absorption near-edge spectroscopy analysis indicated that most of the As in the untreated soil was present as As(V) associated with Fe mineral phases, whereas in the treated soil, the proportion of arsenosiderite increased. Arsenite was present only as a minor species (3-5%) in the treated soils, with the exception

  19. Effect of the phosphogypsum amendment of saline and agricultural soils on growth, productivity and antioxidant enzyme activities of tomato (Solanum lycopersicum L.).

    PubMed

    Smaoui-Jardak, Mariem; Kriaa, Walid; Maalej, Mohamed; Zouari, Mohamed; Kamoun, Lotfi; Trabelsi, Wassim; Ben Abdallah, Ferjani; Elloumi, Nada

    2017-10-01

    The objective of this study was to investigate the effects of phosphogypsum (PG) amendment on the physiochemical proprieties of saline and agricultural soils along with the growth, productivity and antioxidant enzyme activities of tomato plants ( Solanum lycopersicum L.) grown on the amended soils under controlled conditions. Obtained results showed that the amendment of saline soil (H) by PG induced a decrease in pH as well as in electrical conductivity. However, for the non saline soil (MC), there was a decrease in pH associated with an increase in electrical conductivity. For both soils, PG amendment led to an increase in Calcium (Ca) and sodium (Na), and a decrease in potassium (K) in plant tissues. Cadmium (Cd), Zinc (Zn) and Chromium (Cr) contents in different parts of plants increased in proportion with PG concentration in the soils. Apart from Cd, all the analyzed metals in tomato fruit were found to be below the recommended maximum allowable concentration (MAC). Our results showed that PG application, at doses not exceeding 20%, seems to be beneficial for growth, photosynthetic activity and productivity of tomato plants as well as in decreasing salinity of saline soils. In these conditions, the use of PG could be a promising project for the rehabilitation of marginalized and saline ecosystems with either ornamental or non-fruit species. For both soils, a significant accumulation of MDA in shoots was detected, reflecting cell membrane damage especially when the PG amendment reached 20%. Beyond 20 and 40% PG, tomato plants developed an enzymatic antioxidant defense system in response to salinity and heavy metal stress. However, at 80% PG, enzymes activities were significantly inhibited.

  20. Particulate matter emissions from biochar-amended soils as a potential tradeoff to the negative emission potential

    NASA Astrophysics Data System (ADS)

    Ravi, Sujith; Sharratt, Brenton S.; Li, Junran; Olshevski, Stuart; Meng, Zhongju; Zhang, Jianguo

    2016-10-01

    Novel carbon sequestration strategies such as large-scale land application of biochar may provide sustainable pathways to increase the terrestrial storage of carbon. Biochar has a long residence time in the soil and hence comprehensive studies are urgently needed to quantify the environmental impacts of large-scale biochar application. In particular, black carbon emissions from soils amended with biochar may counteract the negative emission potential due to the impacts on air quality, climate, and biogeochemical cycles. We investigated, using wind tunnel experiments, the particulate matter emission potential of a sand and two agriculturally important soils amended with different concentrations of biochar, in comparison to control soils. Our results indicate that biochar application considerably increases particulate emissions possibly by two mechanisms-the accelerated emission of fine biochar particles and the generation and emission of fine biochar particles resulting from abrasion of large biochar particles by sand grains. Our study highlights the importance of considering the background soil properties (e.g., texture) and geomorphological processes (e.g., aeolian transport) for biochar-based carbon sequestration programs.

  1. Exposure of agricultural crops to nanoparticle CeO2 in biochar-amended soil

    USDA-ARS?s Scientific Manuscript database

    Biochar is seeing increased usage as an amendment in agricultural soils but the significance of nanoscale interactions between this additive and engineered nanoparticles (ENP) remains largely unknown. In the present study, corn (Zea mays), lettuce (Lactuca sativa), soybean (Glycine max) and zucchini...

  2. Directed Selection of Biochars for Amending Metal ...

    EPA Pesticide Factsheets

    Approximately 500,000 abandoned mines across the U.S. pose a considerable, pervasive risk to human health and the environment. World-wide the problem is even larger. Lime, organic matter, biosolids and other amendments have been used to decrease metal bioavailability in contaminated mine wastes and to promote the development of a mine waste stabilizing plant cover. The demonstrated properties of biochar make it a viable candidate as an amendment for remediating metal contaminated mine soils. In addition to sequestering potentially toxic metals, biochar can also be a source of plant nutrients, used to adjust soil pH, improve soil water holding characteristics, and increase soil carbon content. However, methods are needed for matching biochar beneficial properties with mine waste toxicities and soil health deficiencies. In this presentation we will report on a study in which we used mine soil from an abandoned Cu and Zn mine to develop a three-step procedure for identifying biochars that are most effective at reducing heavy metal bioavailability. Step 1: a slightly acidic extract of the mine spoil soil was produced, representing the potentially available metals, and used to identify metal removal properties of a library of 38 different biochars (e.g., made from a variety of feedstocks and pyrolysis or gasification conditions). Step 2: evaluation of how well these biochars retained (i.e., did not desorb) previously sorbed metals. Step 3: laboratory evalua

  3. Chelant-enhanced washing of CCA-contaminated soil: Coupled with selective dissolution or soil stabilization.

    PubMed

    Beiyuan, Jingzi; Lau, Abbe Y T; Tsang, Daniel C W; Zhang, Weihua; Kao, Chih-Ming; Baek, Kitae; Ok, Yong Sik; Li, Xiang-Dong

    2018-01-15

    Remediation of CCA-contaminated soil (Cr, Cu, and As) by biodegradable chelant-enhanced washing (EDDS, S,S-ethylene-diamine-disuccinic-acid) needs further enhancement. This study investigated the effectiveness of coupling with pre-treatment by selective dissolution and post-treatment by soil amendments, respectively. Three groups of reagents (reductants, alkaline solvents, and organic ligands) were adopted in the pre-treatment to dissolve the oxide minerals before EDDS extraction. In the post-treatment, soil amendments (coal fly ash (CFA), acid mine drainage sludge (AMDS), green waste compost (GWC)), and their mixtures) were used for a 2-month stabilization after 2-h EDDS washing. Multi-endpoint evaluation was performed by assessing the chemical state, leachability, mobility, bioaccessibility, and plant-availability of residual metal(loid)s as well as the cytotoxicity, enzyme activities, and available nutrients of the treated soils. Pre-treatment by dithionite-citrate-bicarbonate significantly enhanced extraction efficiency, but also increased the leachability of As and Cr and bioaccessibility of Cr in the treated soils. While sodium hydroxide removed the majority of As without increasing its leachability and bioaccessibility, it increased the cytotoxicity and inhibited the acid phosphatase activity. Post-treatment with AMDS and CFA effectively controlled the mobility and leachability of residual As and Cr after EDDS washing. However, destabilized Cu was only marginally immobilized by GWC due to strong Cu-EDDS complexation. The bioaccessibility and phytoavailability of Cu was primarily reduced by EDDS washing, while those of As and Cr could be attenuated by AMDS and CFA. This study indicates that coupling chemical extraction with subsequent soil amendment plays complementary roles in mitigating effects of residual metal(loid)s and improving environmental quality. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. On the acid-base properties of humic acid in soil.

    PubMed

    Cooke, James D; Hamilton-Taylor, John; Tipping, Edward

    2007-01-15

    Humic acid was isolated from three contrasting organic-rich soils and acid-base titrations performed over a range of ionic strengths. Results obtained were unlike most humic acid data sets; they showed a greater ionic strength dependency at low pH than at high pH. Forward- and back-titrations with the base and acid revealed hysteresis, particularly at low pH. Previous authors attributed this type of hysteresis to humic acid aggregates-created during the isolation procedure-being redissolved during titration as the pH increased and regarded the results as artificial. However, forward- and back-titrations with organic-rich soils also demonstrated a similar hysteretic behavior. These observations indicate (i) that titrations of humic acid in aggregated form (as opposed to the more usual dissolved form) are more representative of the acid-base properties of humic acid in soil and (ii) that the ionic strength dependency of proton binding in humic acid is related to its degree of aggregation. Thus, the current use of models based on data from dissolved humic substances to predictthe acid-base properties of humic acid in soil under environmental conditions may be flawed and could substantially overestimate their acid buffering capacity.

  5. Laboratory-scale evaluation of a combined soil amendment for the enhanced biodegradation of propylene glycol-based aircraft de-icing fluids.

    PubMed

    Libisch, Balázs; French, Helen K; Hartnik, Thomas; Anton, Attila; Biró, Borbála

    2012-01-01

    A combined soil amendment was tested in microcosm experiments with an aim to enhance the aerobic biodegradation of propylene glycol (PG)-based aircraft de-icing fluids during and following the infiltration of contaminated snowmelt. A key objective under field conditions is to increase degradation of organic pollutants in the surface soil where higher microbial activity and plant rhizosphere effects may contribute to a more efficient biodegradation of PG, compared to subsoil ground layers, where electron acceptors and nutrients are often depleted. Microcosm experiments were set up in Petri dishes using 50 g of soil mixed with appropriate additives. The samples contained an initial de-icing fluid concentration of 10,000 mg/kg soil. A combined amendment using calcium peroxide, activated carbon and 1 x Hoagland solution resulted in significantly higher degradation rates for PG both at 4 and 22 degrees C. Most probable numbers of bacteria capable of utilizing 10,000 mg/kg de-icing fluid as a sole carbon source were about two orders of magnitude higher in the amended soil samples compared to unamended controls at both temperatures. The elevated numbers of such bacteria in surface soil may be a source of cells transported to the subsoil by snowmelt infiltration. The near-surface application of amendments tested here may enhance the growth of plants and plant roots in the contaminated area, as well as microbes to be found at greater depth, and hence increase the degradation of a contaminant plume present in the ground.

  6. Comparison of the solubilizing efficiencies of some pH lowering (sulphur and (NH4)2SO4) amendments on Cd and Zn mobility in soils.

    PubMed

    Amoakwah, Emmanuel; Van Slycken, Stijn; Essumang, David K

    2014-08-01

    The use of conventional methods to clean up the soil is very expensive and destructive to the ecosystem. The concept of phytoextraction has been introduced to safely manage soils contaminated with heavy metals. However, using plants to remediate polluted soils is a lengthy process. This has necessitated the use of amendments to potentially enhance solubilization of metals in order to increase their bioavailability in the soil solution. A pot experiment was conducted to study the effect of some selected pH lowering amendments [elemental sulphur and (NH4)2SO4] on the solubility and availability of Cd and Zn. The application of these amendments resulted in a decrease in the pH of the soil. The decrease in pH significantly enhanced the solubilization and the mobility of Cd and Zn into the soil solution. The CaCl2 extraction protocol was employed to study the effects of the various amendments on the mobility of Cd and Zn.

  7. Greenhouse gas emission and groundwater pollution potentials of soils amended with raw and carbonized swine solids

    USDA-ARS?s Scientific Manuscript database

    The objective of this research is to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with raw swine solids and swine biochars made from different thermochemical conditions. Triplicate sets of small pots were designed: 1) control soil with a 50/50 mixture o...

  8. Hardwood tree growth on amended mine soils in west virginia.

    PubMed

    Wilson-Kokes, Lindsay; Delong, Curtis; Thomas, Calene; Emerson, Paul; O'Dell, Keith; Skousen, Jeff

    2013-09-01

    Each year surface mining in Appalachia disrupts large areas of forested land. The Surface Mining Control and Reclamation Act requires coal mine operators to establish a permanent vegetative cover after mining, and current practice emphasizes soil compaction and planting of competitive forage grasses to stabilize the site and control erosion. These practices hinder recolonization of native hardwood trees on these reclaimed sites. Recently reclamation scientists and regulators have encouraged re-establishment of hardwood forests on surface mined land through careful selection and placement of rooting media and proper selection and planting of herbaceous and tree species. To evaluate the effect of rooting media and soil amendments, a 2.8-ha experimental plot was established, with half of the plot being constructed of weathered brown sandstone and half constructed of unweathered gray sandstone. Bark mulch was applied to an area covering both sandstone types, and the ends of the plot were hydroseeded with a tree-compatible herbaceous seed mix, resulting in eight soil treatments. Twelve hardwood tree species were planted, and soil chemical properties and tree growth were measured annually from 2007 to 2012. After six growing seasons, average tree volume index was higher for trees grown on brown sandstone (5333 cm) compared with gray sandstone (3031 cm). Trees planted in mulch outperformed trees on nonmulched treatments (volume index of 6187 cm vs. 4194 cm). Hydroseeding with a tree-compatible mix produced greater ground cover (35 vs. 15%) and resulted in greater tree volume index than nonhydroseed areas (5809 vs. 3403 cm). Soil chemical properties were improved by mulch and improved tree growth, especially on gray sandstone. The average pH of brown sandstone was 5.0 to 5.4, and gray sandstone averaged pH 6.9 to 7.7. The mulch treatment on gray sandstone resulted in tree growth similar to brown sandstone alone and with mulch. After 6 yr, tree growth on brown sandstone was

  9. Micro-x-ray fluorescence, micro-x-ray absorption spectroscopy, and micro-x-ray diffraction investigation of lead speciation after the addition of different phosphorus amendments to a smelter-contaminated soil.

    PubMed

    Baker, Lucas R; Pierzynski, Gary M; Hettiarachchi, Ganga M; Scheckel, Kirk G; Newville, Matthew

    2014-03-01

    The stabilization of Pb on additions of P to contaminated soils and mine spoil materials has been well documented. It is clear from the literature that different P sources result in different efficacies of Pb stabilization in the same contaminated material. We hypothesized that the differences in the efficacy of Pb stabilization in contaminated soils on fluid or granular P amendment addition is due to different P reaction processes in and around fertilizer granules and fluid droplets. We used a combination of several synchrotron-based techniques (i.e., spatially resolved micro-X-ray fluorescence, micro-X-ray absorption near-edge structure spectroscopy, and micro-X-ray diffraction) to speciate Pb at two incubation times in a smelter-contaminated soil on addition of several fluid and granular P amendments. The results indicated that the Pb phosphate mineral plumbogummite was an intermediate phase of pyromorphite formation. Additionally, all fluid and granular P sources were able to induce Pb phosphate formation, but fluid phosphoric acid (PA) was the most effective with time and distance from the treatment. Granular phosphate rock and triple super phosphate (TSP) amendments reacted to generate Pb phosphate minerals, with TSP being more effective at greater distances from the point of application. As a result, PA and TSP were the most effective P amendments at inducing Pb phosphate formation, but caution needs to be exercised when adding large amounts of soluble P to the environment. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. Bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure

    USGS Publications Warehouse

    Kinney, C.A.; Furlong, E.T.; Kolpin, D.W.; Burkhardt, M.R.; Zaugg, S.D.; Werner, S.L.; Bossio, J.P.; Benotti, M.J.

    2008-01-01

    Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained a diverse composition of 28 AWIs, reflecting the presence of human-use compounds. The swine manure contained 12 AWIs, and was dominated by biogenic sterols. Soil and earthworm samples were collected in the spring (about 30 days after soil amendment) and fall (140-155 days after soil amendment) at all field sites. Soils from Site 1 contained 21 AWIs and soil from Sites 2 and 3 contained 19 AWIs. The AWI profiles at Sites 2 and 3 generally reflected the relative composition of AWIs present in waste material applied. There were 20 AWIs detected in earthworms from Site 1 (three compounds exceeding concentrations of 1000 ??g/kg), 25 AWIs in earthworms from Site 2 (seven compounds exceeding concentrations of 1000 ??g/kg), and 21 AWIs in earthworms from Site 3 (five compounds exceeding concentrations of 1000 ??g/kg). A number of compounds thatwere present in the earthworm tissue were at concentrations less than reporting levels in the corresponding soil samples. The AWIs detected in earthworm tissue from the three field sites included pharmaceuticals, synthetic fragrances, detergent metabolites, polycyclic aromatic hydrocarbons (PAHs), biogenic sterols, disinfectants, and pesticides, reflecting a wide range of physicochemical properties. For those contaminants detected in earthworm tissue and soil, bioaccumulation factors

  11. Microbial utilization of rice straw and its derived biochar in a paddy soil.

    PubMed

    Pan, Fuxia; Li, Yaying; Chapman, Stephen James; Khan, Sardar; Yao, Huaiying

    2016-07-15

    The application of straw and biochar to soil has received great attention because of their potential benefits such as fertility improvement and carbon (C) sequestration. The abiotic effects of these materials on C and nitrogen (N) cycling in the soil ecosystem have been previously investigated, however, the effects of straw or its derived biochar on the soil microbial community structure and function are not well understood. For this purpose, a short-term incubation experiment was conducted using (13)C-labeled rice straw and its derived biochar ((13)C-labeled biochar) to deepen our understanding about soil microbial community dynamics and function in C sequestration and greenhouse gas emission in the acidic paddy soil amended with these materials. Regarding microbial function, biochar and straw applications increased CO2 emission in the initial stage of incubation and reached the highest level (0.52 and 3.96mgCkg(-1)soilh(-1)) at 1d and 3d after incubation, respectively. Straw amendment significantly (p<0.01) increased respiration rate, total phospholipid fatty acids (PLFAs) and (13)C-PLFA as compared to biochar amendment and the control. The amount and percent of Gram positive bacteria, fungi and actinomycetes were also significantly (p<0.05) higher in (13)C-labeled straw amended soil than the (13)C-labeled biochar amended soil. According to the (13)C data, 23 different PLFAs were derived from straw amended paddy soil, while only 17 PLFAs were derived from biochar amendments. The profile of (13)C-PLFAs derived from straw amendment was significantly (p<0.01) different from biochar amendment. The PLFAs18:1ω7c and cy17:0 (indicators of Gram negative bacteria) showed high relative abundances in the biochar amendment, while 10Me18:0, i17:0 and 18:2ω6,9c (indicators of actinomycetes, Gram positive bacteria and fungi, respectively) showed high relative abundance in the straw amendments. Our results suggest that the function, size and structure of the microbial

  12. Cover crop, soil amendments, and variety effects on organic rice production in Texas

    USDA-ARS?s Scientific Manuscript database

    The major challenges in organic rice production include nutrient improvement, weed management, and variety selection. In this study, we tested the effects of two soil amendments on organic production in southcentral USA. The 2011-12 winter cover crops were established successfully with full coverage...

  13. Establishment of warm season grasses with and without the use of compost soil amendments

    USGS Publications Warehouse

    Perry, M.C.; Osenton, P.C.; Gough, G.A.; Lohnes, E.J.R.

    2000-01-01

    Two compost materials (COMPRO and LEAFGRO) were evaluated as soil amendments to enhance wildlife habitats, while maintaining optimal floral and faunal biodiversity. Special emphasis was placed on the role of compost in the establishment and retention of native warm season grasses (Andropogon gerardi, Schizachyrium scoparium, and Sorghastrum nutans). This study was conducted at two sites that were degraded by previous military and farming operations. Sites were plowed twice in 1996 and then a one inch layer of COMPRO or LEAFGRO was applied with a modified manure spreader and disked into the soil to a depth of 3 inches. Vegetation sampling was conducted in 1996, 1997, 1998, and 1999. Initially the greatest vegetation cover occurred in plots treated with LEAFGRO. Plots treated with COMPRO had less vegetation cover than both types of controls plots (with and without warmseason grasses). The reduced plant growth in the plots treated with COMPRO may have been related to the much higher soil pH of these plots on both sites. In subsequent years, amounts of warm season grasses increased, however, in general there was more cover of warm season grasses in plots that did not receive compost than those that did receive compost. Sorghastrum nutans was more abundant on the sites than either of the other two species of warm season grasses. Invertebrate and mammal data collected for three years indicated that there was not more faunal activity in the plots treated with LEAFGRO or COMPRO compost soil amendments. Results indicate that compost amendments did not improve establishment of warm season grasses and the resultant faunal diversity or abundance.

  14. Soluble organic carbon and pH of organic amendments affect metal mobility and chemical speciation in mine soils.

    PubMed

    Pérez-Esteban, Javier; Escolástico, Consuelo; Masaguer, Alberto; Vargas, Carmen; Moliner, Ana

    2014-05-01

    We evaluated the effects of pH and soluble organic carbon affected by organic amendments on metal mobility to find out the optimal conditions for their application in the stabilization of metals in mine soils. Soil samples (pH 5.5-6.2) were mixed with 0, 30 and 60 th a(-1) of sheep-horse manure (pH 9.4) and pine bark compost (pH 5.7). A single-step extraction procedure was performed using 0.005 M CaCl2 adjusted to pH 4.0-7.0 and metal speciation in soil solution was simulated using NICA-Donnan model. Sheep-horse manure reduced exchangeable metal concentrations (up to 71% Cu, 75% Zn) due to its high pH and degree of maturity, whereas pine bark increased them (32% Cu, 33% Zn). However, at increasing dose and hence pH, sheep-horse manure increased soluble Cu because of higher soluble organic carbon, whereas soluble Cu and organic carbon increased at increasing dose and correspondingly decreasing pH in pine bark and non-amended treatments. Near the native pH of these soils (at pH 5.8-6.3), with small doses of amendments, there was minimum soluble Cu and organic carbon. Pine bark also increased Zn solubility, whereas sheep-horse manure reduced it as soluble Zn always decreased with increasing pH. Sheep-horse manure also reduced the proportion of free metals in soil solution (from 41% to 4% Cu, from 97% to 94% Zn), which are considered to be more bioavailable than organic species. Sheep-horse manure amendment could be efficiently used for the stabilization of metals with low risk of leaching to groundwater at low doses and at relatively low pH, such as the native pH of mine soils. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Elemental composition and functional groups in soil labile organic matter fractions

    USDA-ARS?s Scientific Manuscript database

    Labile organic matter fractions are major components involved in nutrient cycle in soil. In this chapter, we examine three labile organic matter fraction: light fraction (LF), humic acid (HA) and fulvic acid (HA) in Alabama cotton soils (ultisol) amended with chemical fertilizer (NH4NO3) and poult...

  16. Amending greenroof soil with biochar to affect runoff water quantity and quality.

    PubMed

    Beck, Deborah A; Johnson, Gwynn R; Spolek, Graig A

    2011-01-01

    Numbers of greenroofs in urban areas continue to grow internationally; so designing greenroof soil to reduce the amount of nutrients in the stormwater runoff from these roofs is becoming essential. This study evaluated changes in extensive greenroof water discharge quality and quantity after adding biochar, a soil amendment promoted for its ability to retain nutrients in soils and increase soil fertility. Prototype greenroof trays with and without biochar were planted with sedum or ryegrass, with barren soil trays used as controls. The greenroof trays were subjected to two sequential 7.4cm/h rainfall events using a rain simulator. Runoff from the rain events was collected and evaluated. Trays containing 7% biochar showed increased water retention and significant decreases in discharge of total nitrogen, total phosphorus, nitrate, phosphate, and organic carbon. The addition of biochar to greenroof soil improves both runoff water quality and retention. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Long term impact of organic amendments on forest soil properties under semiarid Mediterranean climatic conditions

    NASA Astrophysics Data System (ADS)

    Hueso González, Paloma; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

    2017-04-01

    Soil degradation affects more than 52 million ha of land in countries of the European Union (Hueso-González et al., 2016). This problema is particularly serious in Mediterranean areas, where the effects of anthropogenic activities (tillage on slopes, deforestation, and pasture production) add to problems caused by prolonged periods of drought and intense and irregular rainfall (Martínez-Murillo et al., 2016). Depending on the scale of study, soil organic carbón (SOC) dynamics in Mediterranean forests have been found to be particularly sensitive to factors related to seasonal changes in temperature and soil moisture (Casals et al., 2000; Eaton et al., 2008; Hueso-González et al., 2014). During dry periods in theMediterranean area, the lack of water entering the soil matrix reduces organic contributions to the soil (Parras-Alcántara et al., 2016). These processes lead to reduced soil fertility and soil loss (García-Orenes et al., 2010). Restoring the native vegetation is one of the most effective ways to control soil degradation in Mediterranean areas, especially in very degraded areas. In the initial months after afforestation, vegetation cover establishment and soil quality could be better sustained if the soil was amended with an external extra source of organic matter (Hueso-González et al., 2016). The goal of this study was to test the effect of various organic amendments on select soil properties over a 54-month period. Five amendments were applied in an experimental set of plots: straw mulching (SM), mulch with chipped branches of Aleppo Pine (Pinus halepensis L.; PM), sheep manure compost (SH), hydroabsorbent polymers (HP) and sewage sludge (RU). Plots were afforested following the same spatial pattern, and amendments were mixed with the soil at the rate 10Mg ha-1. Soil from the afforested plots was sampled in the following: (i) spring 2012 (6 months postafforestation); (ii) spring 2013(18 months postafforestation); (iii) spring 2014 (30 months

  18. Misrepresentation and amendment of soil moisture in conceptual hydrological modelling

    NASA Astrophysics Data System (ADS)

    Zhuo, Lu; Han, Dawei

    2016-04-01

    Although many conceptual models are very effective in simulating river runoff, their soil moisture schemes are generally not realistic in comparison with the reality (i.e., getting the right answers for the wrong reasons). This study reveals two significant misrepresentations in those models through a case study using the Xinanjiang model which is representative of many well-known conceptual hydrological models. The first is the setting of the upper limit of its soil moisture at the field capacity, due to the 'holding excess runoff' concept (i.e., runoff begins on repletion of its storage to the field capacity). The second is neglect of capillary rise of water movement. A new scheme is therefore proposed to overcome those two issues. The amended model is as effective as its original form in flow modelling, but represents more logically realistic soil water processes. The purpose of the study is to enable the hydrological model to get the right answers for the right reasons. Therefore, the new model structure has a better capability in potentially assimilating soil moisture observations to enhance its real-time flood forecasting accuracy. The new scheme is evaluated in the Pontiac catchment of the USA through a comparison with satellite observed soil moisture. The correlation between the XAJ and the observed soil moisture is enhanced significantly from 0.64 to 0.70. In addition, a new soil moisture term called SMDS (Soil Moisture Deficit to Saturation) is proposed to complement the conventional SMD (Soil Moisture Deficit).

  19. Assessing the stability in dry mycelial fertilizer of Penicillium chrysogenum as soil amendment via fluorescence excitation-emission matrix spectra: organic matter's transformation and maturity.

    PubMed

    Wang, Bing; Cai, Chen; Li, Guomin; Liu, Huiling

    2017-12-01

    Utilization as dry mycelial fertilizer (DMF) produced from penicillin fermentation fungi mycelium (PFFM) with an acid-heating pretreatment is a potential way. To study the transformation and stability of water-extractable organic matter in DMF-amended soil via fluorescence regional integration (FRI) of fluorescence excitation-emission matrix (EEM), a soil experiment in pot was carried out. The results showed that residual penicillin (about 32 mg/kg) was almost degraded in the first 5 days, indicating that the drug pollution was in control. The pH value, DOC, DON, and DOC/DON presented a classical profile, but germination index (GI) leveled off about 0.13 till day 13 in DMF-12% treatment due to the severe phytotoxicity. The addition of DMF significantly increased the soil microbial populations in contrast to the CON treatment. The EEM showed that the protein-like and microbial byproduct-like matters vanished on the 25th and 33rd days, whereas the fulvic-like substances appeared on the 7th day. The humic-like substances existed in original samples but their content greatly enhanced finally. The FRI results showed that P V, n /P III, n reached the highest value of 1.84 on the 25th day, suggesting that DMF maintained stable in amended soil. Because of its consistency with the results of GI and DOC/DON, the EEM-FRI has a potential to evaluate the stability of DMF in soil.

  20. PAH-sequestration capacity of granular and powder activated carbon amendments in soil, and their effects on earthworms and plants.

    PubMed

    Jakob, Lena; Hartnik, Thomas; Henriksen, Thomas; Elmquist, Marie; Brändli, Rahel C; Hale, Sarah E; Cornelissen, Gerard

    2012-07-01

    A field lysimeter study was carried out to investigate whether the amendment of 2% powder and granular activated carbon (PAC and GAC) to a soil with moderate PAH contamination had an impact on the PAH bioaccumulation of earthworms and plants, since AC is known to be a strong sorbent for organic pollutants. Furthermore, secondary effects of AC on plants and earthworms were studied through growth and nutrient uptake, and survival and weight gain. Additionally, the effect of AC amendments on soil characteristics like pH, water holding capacity, and the water retention curve of the soil were investigated. Results show that the amendment of 2% PAC had a negative effect on plant growth while the GAC increased the growth rate of plants. PAC was toxic to earthworms, demonstrated by a significant weight loss, while the results for GAC were less clear due to ambiguous results of a field and a parallel laboratory study. Both kinds of AC significantly reduced biota to soil accumulation factors (BSAFs) of PAHs in earthworms and plants. The GAC reduced the BSAFs of earthworms by an average of 47 ± 44% and the PAC amendment reduced them by 72 ± 19%. For the investigated plants the BSAFs were reduced by 46 ± 36% and 53 ± 22% by the GAC and PAC, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Effect of biochar soil-amendments on Allium porrum growth, arbuscular mycorrhizal fungus colonization

    USDA-ARS?s Scientific Manuscript database

    Aims: Examine the interaction of biochar addition and arbuscular mycorrhizal [AM] fungus inoculation upon growth and Zn and Cu uptake by Allium porrum L. in heavy metal amended soil mix, and relate these responses to physicochemical properties of the biochars. Methods: The experiment was a complete ...

  2. Phosphorus distribution in soils amended with bioenergy co-product materials following corn growth

    USDA-ARS?s Scientific Manuscript database

    Biochar is a carbonaceous co-product that results from pyrolysis of organic material in the absence of oxygen produced for use as a soil amendment. Pyrolysis, gasification, and combustion are three processes being investigated and/or used to convert biomass into renewable energy and other products. ...

  3. Radical change of Zn speciation in pig slurry amended soil: Key role of nano-sized sulfide particles.

    PubMed

    Formentini, Thiago Augusto; Legros, Samuel; Fernandes, Cristovão Vicente Scapulatempo; Pinheiro, Adilson; Le Bars, Maureen; Levard, Clément; Mallmann, Fábio Joel Kochem; da Veiga, Milton; Doelsch, Emmanuel

    2017-03-01

    Spreading livestock manure as fertilizer on farmlands is a widespread practice. It represents the major source of heavy metal(loid)s (HM) input in agricultural soils. Since zinc (Zn) is present at high concentrations in manure, it poses special environmental concerns related to phytotoxicity, groundwater contamination, and introduction in the food chain. Therefore, investigations on the fate and behavior of manure-borne Zn, when it enters the soil environment, are necessary to predict the environmental effects. Nevertheless, long-term field studies assessing Zn speciation in the organic waste matrix, as well as within the soil after manure application, are lacking. This study was designed to fill this gap. Using SEM-EDS and XAS analysis, we reported the following new results: (i) ZnS made up 100% of the Zn speciation in the pig slurry (the highest proportion of ZnS ever observed in organic waste); and (ii) ZnS aggregates were about 1-μm diameter (the smallest particle size ever reported in pig slurry). Moreover, the pig slurry containing ZnS was spread on the soil over an 11-year period, totaling 22 applications, and the resulting Zn speciation within the amended soil was analyzed. Surprisingly, ZnS, i.e. the only species responsible for a nearly 2-fold increase in the Zn concentration within the amended soil, was not detected in this soil. Based on SEM-EDS and XAS observations, we put forward the hypothesis that Zn in the pig slurry consisted of nano-sized ZnS crystallites that further aggregated. The low stability of ZnS nanoparticles within oxic and complex environments such as the studied soil was the key explanation for the radical change in pig slurry-borne Zn speciation after long-term amendments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. 77 FR 73934 - Bacillus subtilis Strain QST 713 Variant Soil; Amendment to an Exemption From the Requirement of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... subtilis Strain QST 713 Variant Soil; Amendment to an Exemption From the Requirement of a Tolerance for Bacillus subtilis Strain QST 713 To Include Residues of Bacillus subtilis Strain QST 713 Variant Soil... in or on all food commodities by including residues of Bacillus subtilis strain QST 713 variant soil...

  5. Perfluoroalkyl acid distribution in various plant compartments ...

    EPA Pesticide Factsheets

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids­ amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA;232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root­ soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with incre

  6. Effects of N-ammonoxidized lignins amendment on N availability and soil fertility: An incubation study

    NASA Astrophysics Data System (ADS)

    María De la Rosa, José; López-Martín, María; Liebner, Falk; Knicker, Heike

    2013-04-01

    The shift towards a biobased economy will probably generate the application of bioenergy by-products and charred residues to the soil as either amendments or fertilizers. The process of ammonoxidation (application of gaseous oxygen and aqueous ammonia under ambient pressure breaks down aromatic lignin moieties and introduces N in the form of urea, amides and amines), converts lignin, a major by-product of the pulp and paper industry, or other ligneous materials into artificial humic matter (N-lignin). The use of N-ammonoxidized lignin as soil improvers is in theory an economically viable solution, especially interesting for agricultural areas of Mediterranean countries, in which additional factors such as water shortage and fires contribute to declining N availability by lowering nutrient diffusion, litter input or sequestration of N in charred structures. However, limited research has been done to determine how this will influence C and N dynamics and soil fertility. Therefore we performed pot experiments in which a perennial ryegrass (Lolium perenne L.) was grown on a typical Andalusian soil (chromic Luvisol) after amendment of N-lignins highly enriched in 15N (Sarkanda and Indulin ammonoxidized lignins) for 75 days. For comparison, the incubation was also carried out on soils fertilized with 15NO3 and unfertilized (control). The application of ammonoxidized lignins altered the pH and electrical conductivity of the soil. At higher concentrations a retardation of seed germination was evidenced, an observation that needs further considerations before N-enriched technical lignins can be applied in agriculture. After 75 days, the plant shoots from the pots amended with15N-Indulin and 15N-Sarkanda accumulated 8% and 20%, respectively of the initial 15N (15N0). The N was efficiently sequestered from fast release or leaching and most of 15N0 remained in the soil (64%) in the 15N-Indulin pots. In contrast, the 15N-Sarkanda pots showed a lower efficiency in the N

  7. Phytotoxicity of nitroaromatic energetic compounds freshly amended or weathered and aged in sandy loam soil.

    PubMed

    Rocheleau, Sylvie; Kuperman, Roman G; Martel, Majorie; Paquet, Louise; Bardai, Ghalib; Wong, Stephen; Sarrazin, Manon; Dodard, Sabine; Gong, Ping; Hawari, Jalal; Checkai, Ronald T; Sunahara, Geoffrey I

    2006-01-01

    The toxicities of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 2,4-dinitrotoluene (2,4-DNT), and 2,6-dinitrotoluene (2,6-DNT) to terrestrial plants alfalfa (Medicago sativa L.), Japanese millet (Echinochloa crusgalli L.), and perennial ryegrass (Lolium perenne L.) were determined in Sassafras sandy loam soil using seedling emergence, fresh shoot, and dry mass measurement endpoints. A 13-week weathering and aging of energetic materials in soils, which included wetting and drying cycles, and exposure to sunlight of individual soil treatments, was incorporated into the study design to better reflect the soil exposure conditions in the field than toxicity determinations in freshly amended soils. Definitive toxicity tests showed that dinitrotoluenes were more phytotoxic for all plant species in freshly amended treatments based on EC20 values for dry shoot ranging from 3 to 24mgkg(-1) compared with values for TNB or TNT ranging from 43 to 62mgkg(-1). Weathering and aging of energetic materials (EMs) in soil significantly decreased the toxicity of TNT, TNB or 2,6-DNT to Japanese millet or ryegrass based on seedling emergence, but significantly increased the toxicity of all four EMs to all three plant species based on shoot growth. Exposure of the three plant species to relatively low concentrations of the four compounds initially stimulated plant growth before the onset of inhibition at greater concentrations (hormesis).

  8. Nodulation of cowpeas and survival of cowpeas Rhizobia in acid, aluminum-rich soils. [Vigna unguiculata; Rhizobium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartel, P.G.; Whelan, A.M.; Alexander, M.

    1983-01-01

    A study was undertaken to determine whether the reduced nodulation of cowpeas (Vigna unguiculata (L.) Walp) grown in certain acid, Alrich soils resulted from the poor survival of the potentially infective rhizobia. Two strains of Rhizobium capable of nodulating cowpeas were used. The lowest pH for growth in defined liquid medium was 4.2 for one strain and 3.9 for the other. Only the latter was Al tolerant and could grow in a defined liquid medium containing 50 ..mu..M KAl(SO/sub 4/)/sub 2/. The survival of the bacteria and their ability to nodulate cowpeas in three soils were measured after the soilsmore » were amended with Ca or Al salts to give pH values ranging from 5.7 to 4.1 and extractable-Al concentrations from < 0.1 to 3.7 cmol(p/sup +/)/kg of soil. Only small differences in survival in 7 or 8 weeks were noted between the two strains. Plants inoculated with the Al-sensitive strain bore significantly fewer nodules in the more acid, Al-rich soils than in the same soils with higher pH values and less extractable Al. No significant reduction in nodule number was evident for plants inoculated with the Al-tolerant strain and grown in the more acid, Al-rich soils compared to cowpeas grown in the same soils with higher pH values and less extractable Al. It is suggested that the Al content of soil is not a major factor in the survival of cowpea rhizobia but that it does have a significant effect on nodulation. 24 references, 3 figures, 2 tables.« less

  9. Effect of different amendments on rice (Oryza sativa L.) growth, yield, nutrient uptake and grain quality in Ni-contaminated soil.

    PubMed

    Ramzani, Pia Muhammad Adnan; Khan, Waqas-Ud-Din; Iqbal, Muhammad; Kausar, Salma; Ali, Shafaqat; Rizwan, Muhammad; Virk, Zaheer Abbas

    2016-09-01

    Rice ( Oryza sativa L.) is one of the main staple food crops which is inherently low in micronutrients, especially iron (Fe), and can lead to severe Fe deficiency in populations having higher consumption of rice. Soils polluted with nickel (Ni) can cause toxicity to rice and decreased Fe uptake by rice plants. We investigated the potential role of biochar (BC) and gravel sludge (GS), alone and in combination, for in situ immobilization of Ni in an industrially Ni-contaminated soil at original and sulfur-amended altered soil pH. Our further aim was to increase Fe bioavailability to rice plants by the exogenous application of ferrous sulfate to the Ni-immobilized soil. Application of the mixture of both amendments reduced grain Ni concentration, phytate, Phytate/Fe, Phyt/Zn molar ratios, and soil DTPA-extractable Ni. In addition, the amendment mixture increased 70 % Fe and 229 % ferritin concentrations in rice grains grown in the soil at original pH. The Fe and ferritin concentrations in S-treated soil was increased up to 113 and 383 % relative to control respectively. This enhanced Fe concentration and corresponding ferritin in rice grains can be attributed to Ni/Fe antagonism where Ni has been immobilized by GS and BC mixture. This proposed technique can be used to enhance growth, yield, and Fe biofortification in rice by reducing soil pH while in parallel in situ immobilizing Ni in polluted soil.

  10. Lead stabilization by phosphate amendments in soil impacted by paint residue.

    PubMed

    Schwab, A P; Lewis, K; Banks, M K

    2006-01-01

    The addition of phosphate was evaluated for contaminant stabilization in soils impacted by lead paint residue. Soils sampled from 15 highway bridge sites in Indiana were screened based on residual lead concentrations from paint contamination. Two appropriate bridge sites were identified in Tippecanoe County, Indiana. Soluble phosphate was added to the soil at a mole ratio of 3:1 P:Pb. The efficacy of phosphate treatment was evaluated by a physiologically based extraction test (PBET), uptake of lead by sunflowers, and leaching of lead from soil columns. Sunflowers were established on both field sites, and the mean Pb concentration in the above-ground biomass indicated that the rate of uptake was similar to plants growing in uncontaminated soil. The second bioavailability assessment was the physiologically based extraction test, designed to evaluate heavy metal availability during ingestion. After 1 year at both sites, the addition of phosphate significantly reduced the concentrations of lead extracted by PBET, indicating that the lead in the amended soils had lower bioavailability than in the unamended soils. In the column study, the contaminated soil produced the highest mass of leached Pb, and the addition of P reduced the mass of Pb in the leachate to similar levels found in the uncontaminated soil. Overall, the addition of soluble phosphate to these soils appears to be an effective approach for immobilizing Pb and reducing the associated bio-accessibility.

  11. Impact of biochar amendment on soil water soluble carbon in the context of extreme hydrological events.

    PubMed

    Wang, Daoyuan; Griffin, Deirdre E; Parikh, Sanjai J; Scow, Kate M

    2016-10-01

    Biochar amendments to soil have been promoted as a low cost carbon (C) sequestration strategy as well as a way to increase nutrient retention and remediate contaminants. If biochar is to become part of a long-term management strategy, it is important to consider its positive and negative impacts, and their trade-offs, on soil organic matter (SOM) and soluble C under different hydrological conditions such as prolonged drought or frequent wet-dry cycles. A 52-week incubation experiment measuring the influence of biochar on soil water soluble C under different soil moisture conditions (wet, dry, or wet-dry cycles) indicated that, in general, dry and wet-dry cycles increased water soluble C, and biochar addition further increased release of water soluble C from native SOM. Biochar amendment appeared to increase transformation of native SOM to water soluble C, based on specific ultraviolet absorption (SUVA) and C stable isotope composition; however, the increased amount of water soluble C from native SOM is less than 1% of total biochar C. The impacts of biochar on water soluble C need to be carefully considered when applying biochar to agricultural soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Differences on nitrogen availability in a soil amended with fresh, composted and thermally-dried sewage sludge.

    PubMed

    Tarrasón, D; Ojeda, G; Ortiz, O; Alcañiz, J M

    2008-01-01

    Anaerobically-digested sludge called fresh sludge (F), composted sludge (C) and thermally-drying sludge (T), all from the same batch, were applied to the surface of a calcareous Udic Calciustept with loamy texture. Dosage equivalent was 10 t ha(-1) of dry matter. The concentration of mineral nitrogen (ammonium and nitrate) in the soil was measured in order to estimate the effects of the post-treatments to which the different kinds of sewage sludge are subjected in relation to the availability of N in the surface layer of the soil. The most significant differences in NH(4)-N and NO(3)-N concentrations due to the transformation of the organic matter were observed during the first three weeks following soil amendment. Thermally-dried and composted sludge initially displayed higher concentrations of ammonium and nitrate in soil. Five months after the amendment, soil applied with fresh sludge showed the highest concentrations of NH(4)-N and NO(3)-N (6.1 and 36.6 mg kg(-1), respectively). It is clear that the processes of composting and thermal-drying influence the bioavailability of nitrogen from the different types of sewage sludge.

  13. Factors affecting emission of AITC and subsequent disease control efficacy of Brassica juncea seed meal soil amendment

    USDA-ARS?s Scientific Manuscript database

    Soil physical conditions demonstrably affected allyl isothiocyanate (AITC) emitted from Brassica juncea cv Pacific Gold seed meal (SM) amended soil. The AITC concentration detected increased with an increase in temperature from 10 oC to 30 oC. AITC concentration also increased with an increase in so...

  14. Release of cadmium in contaminated paddy soil amended with NPK fertilizer and lime under water management.

    PubMed

    Han, Xiao-Qing; Xiao, Xi-Yuan; Guo, Zhao-Hui; Xie, Ye-Hua; Zhu, Hui-Wen; Peng, Chi; Liang, Yu-Qin

    2018-05-03

    Agricultural soils contaminated with cadmium (Cd) pose a risk to receiving surface water via drainage or runoff. A 90-day laboratory incubation experiment was conducted to investigate the release characteristics and transformation of Cd from contaminated paddy soil amended with agrochemical (NPK fertilizer) and lime (L) under water management regimes of continuous flooding (F) and drying-wetting cycles (DW). The result showed that the dissolved Cd concentrations in overlying water of the fertilizer treatment under flooding (NPK+F) and drying-wetting (NPK+DW) reached up to 81.0 μg/L and 276 μg/L, and were much higher than that from the corresponding controls without NPK fertilizer addition at the end of experiment. The Cd concentration showed significantly negative correlation with overlying water pH, but positive correlation with soil redox potential and concentrations of dissolved total nitrogen, sulfate and manganese in overlying water (P < 0.05), indicating that drying-wetting cycles and N fertilizer addition may enhance soil Cd release. The Cd concentrations in overlying water from all treatments except NPK+L+F treatment exceeded the Cd threshold limit of Chinese Environmental Quality Standards for Surface Water (10 μg/L Grade V) and poses potential risk to surface water quality. Meanwhile, the proportion of Cd in the acid-soluble fraction from all incubated soil except NPK+L+F treatment increased compared to before incubation. The results indicated that continuous flooding was a reasonable water management candidate coupled with lime addition for immobilizing soil Cd. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Assessing the combination of iron sulfate and organic materials as amendment for an arsenic and copper contaminated soil. A chemical and ecotoxicological approach.

    PubMed

    Fresno, Teresa; Moreno-Jiménez, Eduardo; Peñalosa, Jesús M

    2016-12-01

    The efficiency of combining iron sulfate and organic amendments (paper mill sludge, olive mill waste compost and olive tree pruning biochar) for the remediation of an As- and Cu-contaminated soil was evaluated. Changes in As and Cu fractionation and solubility due to the application of the amendments was explored by leachate analysis, single and sequential extractions. Also, the effects on Arrhenatherum elatius growth, germination of Lactuca sativa and toxicity to the bacteria Vibrio fischeri were assessed. The combination of iron sulfate and the organic amendments efficiently reduced As solubility and availability through the formation of amorphous iron oxides, while organic matter did not seem to mobilize As. At the same time, copper fractionation was strongly affected by soil pH and organic matter addition. The soil pH significantly influenced both As and Cu mobility. Within all the amendments tested, FeSO 4 in combination with compost showed to be the most suitable treatment for the overall remediation process, as it reduced As and Cu availability andenhanced soil nutrient concentrations and plant growth. In sipte of contradictory trends between chemical analyses and ecotoxicity tests, we can still conclude that the application of organic amendments in combination with reactive iron salts is a suitable approach for the remediation of soils contaminated by Cu and As. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Efficacy of several soil amendments for the control of Xiphinema index and Meloidogyne javanica on grapevine seedlings in Pakistan

    USDA-ARS?s Scientific Manuscript database

    This study was done to investigate the effect of several organic amendments for the control of plant-parasitic nematodes. The effects of four soil amendments applied individually or in several combinations and a chemical nematicide (carbofuran) on plant-parasitic nematodes associated with the rhizos...

  17. [Effects of selective microbial inhibitors on the microbial transformation of phosphorous in aggregates of highly weathered red soil with rice straw amendment].

    PubMed

    Ding, Long-jun; Xiao, He-ai; Wu, Jin-shui; Ge, Ti-da

    2010-07-01

    In order to further understand the mechanisms of microbial immobilization of phosphorous (P) in highly weathered red soil with organic amendment, an incubation test was conducted to investigate the roles of microbial functional groups in the transformation of P in 0.2-2 mm soil aggregates. Throughout the 90-day incubation period, amendment with rice straw induced a substantial increase in the amounts of microbial biomass C and P, Olsen-P, and organic P in the aggregates. Comparing with rice straw amendment alone, the amendment with rice straw plus fungal inhibitor actidione decreased the amount of microbial biomass C in the aggregates by 10.5%-31.8% in the first 30 days. Such a decrement was significantly larger than that (6.8%-11.6%) in the treatment amended with rice straw plus bacterial inhibitors tetracycline and streptomycin sulphate (P<0.01). After the first 30 days, the microbial biomass C remained constant. In the first 20 days, the amount of microbial biomass P in the aggregates was 10.0%-28.8% higher in the treatment amended with bacterial inhibitors than in the treatment amended with fungal inhibitor (P<0.01). All the results suggested that that both the fungal and the bacterial groups were involved in the microbial immobilization of P in the soil aggregates, and the fungal group played a relatively larger role.

  18. A comparison of in situ methods for measuring net nitrogen mineralization rates of organic soil amendments.

    PubMed

    Hanselman, Travis A; Graetz, Donald A; Obreza, Thomas A

    2004-01-01

    In situ incubation methods may help provide site-specific estimates of N mineralization from land-applied wastes. However, there are concerns about the reliability of the data generated by the various methods due to containment artifacts. We amended a sandy soil with either poultry manure, biosolids, or yard-waste compost and incubated the mixtures using four in situ methods (buried bags, covered cylinders, standard resin traps, and "new" soil-resin traps) and a conventional laboratory technique in plastic bags. Each incubation device was destructively sampled at 45-d intervals for 180 d and net N mineralization was determined by measuring the amount of inorganic N that accumulated in the soil or soil plus resin traps. Containment effects were evaluated by comparing water content of the containerized soil to a field-reference soil column. In situ incubation methods provided reasonable estimates of short-term (< 45 d) N mineralization, but long-term (> 45 d) mineralization data were not accurate due to a variety of problems specific to each technique. Buried bags and covered cylinders did not retain mineralized N due to water movement into and out of the containers. Neither resin method captured all of the mineralized N that leached through the soil columns, but the new soil-resin trap method tracked field soil water content better than all other in situ methods evaluated. With further refinement and validation, the new soil-resin trap method may be a useful in situ incubation technique for measuring net N mineralization rates of organic soil amendments.

  19. Evolution of organic matter fractions after application of co-compost of sewage sludge with pruning waste to four Mediterranean agricultural soils. A soil microcosm experiment.

    PubMed

    Pérez-Lomas, A L; Delgado, G; Párraga, J; Delgado, R; Almendros, G; Aranda, V

    2010-10-01

    The effect of co-compost application from sewage sludge and pruning waste, on quality and quantity of soil organic carbon (SOC) in four Mediterranean agricultural soils (South Spain), was studied in soil microcosm conditions. Control soil samples (no co-compost addition) and soils treated with co-composts to a rate equivalent of 140 Mg ha(-1) were incubated for 90 days at two temperatures: 5 and 35 degrees C. The significances of incubation temperature and the addition of co-compost, on the evolution of the different fractions of SOC, were studied using a 2(3) factorial design. The co-compost amendment increased the amounts of humic fractions: humic acids (HA) (1.9 times), fulvic acids (FA) (3.3 times), humin (1.5 times), as well as the free organic matter (1.4 times) and free lipids (21.8 times). Incubation of the soils enhanced its biological activity mainly in the amended soils and at 35 degrees C, leading to progressive SOC mineralization and humification, concomitant to the preferential accumulation of HA. The incubation results show large differences depending on temperature and soil types. This fact allows us to select suitable organic amendment for the soil when a rapid increase in nutrients through mineralization is preferred, or in cases intending the stabilization and preservation of the SOC through a process of humification. In soils with HA of more than 5 E(4)/E(6) ratio, the incubation temperature increased rates of mineralization and humification, whereas lower temperatures limited the extent of both processes. In these soils the addition of co-compost in spring or summer is the most recommendable. In soils with HA of lower E(4)/E(6) ratio (<5), the higher temperature favoured mineralization but not humification, whereas the low temperature maintained the SOC levels and even increased the HA/FA ratio. In these soils the moment of addition of organic amendment should be decided depending on the effect intended. On the other hand, the lower the SOC

  20. Effect of inorganic amendments for in situ stabilization of cadmium in contaminated soils and its phyto-availability to wheat and rice under rotation.

    PubMed

    Rehman, Muhammad Zia-ur; Rizwan, Muhammad; Ghafoor, Abdul; Naeem, Asif; Ali, Shafaqat; Sabir, Muhammad; Qayyum, Muhammad Farooq

    2015-11-01

    Cadmium (Cd) toxicity is a widespread problem in crops grown on contaminated soils, and little information is available on the role of inorganic amendments in Cd immobilization, uptake, and tolerance in crops especially under filed conditions. The effect of three amendments, monoammonium phosphate (MAP), gypsum, and elemental sulfur (S), on Cd immobilization in soil and uptake in wheat and rice plants, under rotation, were investigated under field conditions receiving raw city effluent since >20 years and contaminated with Cd. Three levels of each treatment, 0.2, 0.4, and 0.8% by weight, were applied at the start of the experiment, and wheat was sown in the field. After wheat harvesting, rice was sown in the same field without application of amendments. Both crops were harvested at physiological maturity, and data regarding grain yield, straw biomass, Cd concentrations, and uptake in grain and straw, and bioavailable Cd in soil and soil pH were recorded. Both MAP and gypsum application increased grain yield and biomass of wheat and rice, while S application did not increase the yield of both crops. MAP and gypsum amendments decreased gain and straw Cd concentrations and uptake in both crops, while S application increased Cd concentrations in these parts which were correlated with soil bioavailable Cd. We conclude that MAP and gypsum amendments could be used to decrease Cd uptake by plants receiving raw city effluents, and gypsum might be a better amendment for in situ immobilization of Cd due to its low cost and frequent availability.

  1. Relative contribution of maize and external manure amendment to soil carbon sequestration in a long-term intensive maize cropping system

    PubMed Central

    Zhang, Wenju; Liu, Kailou; Wang, Jinzhou; Shao, Xingfang; Xu, Minggang; Li, Jianwei; Wang, Xiujun; Murphy, Daniel V.

    2015-01-01

    We aimed to quantify the relative contributions of plant residue and organic manure to soil carbon sequestration. Using a 27-year-long inorganic fertilizer and manure amendment experiment in a maize (Zea mays L.) double-cropping system, we quantified changes in harvestable maize biomass and soil organic carbon stocks (0–20 cm depth) between 1986-2012. By employing natural 13C tracing techniques, we derived the proportional contributions of below-ground crop biomass return (maize-derived carbon) and external manure amendment (manure-derived carbon) to the total soil organic carbon stock. The average retention of maize-derived carbon plus manure-derived carbon during the early period of the trial (up to 11 years) was relatively high (10%) compared to the later period (22 to 27 years, 5.1–6.3%). About 11% of maize-derived carbon was converted to soil organic carbon, which was double the retention of manure-derived carbon (4.4–5.1%). This result emphasized that organic amendments were necessary to a win-win strategy for both SOC sequestration and maize production. PMID:26039186

  2. Trace metal mobilization by organic soil amendments: insights gained from analyses of solid and solution phase complexation of cadmium, nickel and zinc.

    PubMed

    Welikala, Dharshika; Hucker, Cameron; Hartland, Adam; Robinson, Brett H; Lehto, Niklas J

    2018-05-01

    The accumulation of Cd in soils worldwide has increased the demand for methods to reduce the metal's plant bioavailability. Organic matter rich soil amendments have been shown to be effective in achieving this. However, it is not known how long these amendments can retain the Cd, and whether dissolved organic matter (DOM) released from them can enhance the metal's mobility in the environment. In this study we sought to test the Cd binding capacity of various organic soil amendments, and evaluate differences in characteristics of the DOM released to see if they can explain the lability of the Cd-DOM complexes. We collected ten organic soil amendments from around New Zealand: five different composts, biosolids from two sources, two types of peat and spent coffee grounds. We characterised the amendments' elemental composition and their ability to bind the Cd. We then selected two composts and two peats for further tests, where we measured the sorption of Ni or Zn by the amendments. We analysed the quality of the extracted DOM from the four amendments using 3D Excitation Emission Matrix analysis, and tested the lability of the metal-DOM complexes using an adapted diffusive gradients in thin-films (DGT) method. We found that composts bound the most Cd and that the emergent Cd-DOM complexes were less labile than those from the peats. Ni-DOM complexes were the least labile. The aromaticity of the extracted DOM appears to be an important factor in determining the lability of Ni complexes, but less so for Zn and Cd. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Biochar amendment reduced methylmercury accumulation in rice plants.

    PubMed

    Shu, Rui; Wang, Yongjie; Zhong, Huan

    2016-08-05

    There is growing concern about methylmercury (MeHg) accumulation in rice grains and thus enhanced dietary exposure to MeHg in Asian countries. Here, we explored the possibility of reducing grain MeHg levels by biochar amendment, and the underlying mechanisms. Pot (i.e., rice cultivation in biochar amended soils) and batch experiments (i.e., incubation of amended soils under laboratory conditions) were carried out, to investigate MeHg dynamics (i.e., MeHg production, partitioning and phytoavailability in paddy soils, and MeHg uptake by rice) under biochar amendment (1-4% of soil mass). We demonstrate for the first time that biochar amendment could evidently reduce grain MeHg levels (49-92%). The declines could be attributed to the combined effects of: (1) increased soil MeHg concentrations, probably explained by the release of sulfate from biochar and thus enhanced microbial production of MeHg (e.g., by sulfate-reducing bacteria), (2) MeHg immobilization in soils, facilitated by the large surface areas and high organosulfur content of biochar, and (3) biodilution of MeHg in rice grains, due to the increased grain biomass under biochar amendment (35-79%). These observations together with mechanistic explanations improve understanding of MeHg dynamics in soil-rice systems, and support the possibility of reducing MeHg phytoaccumulation under biochar amendment. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Effect of long term organic amendments and vegetation of vineyard soils on the microscale distribution and biogeochemistry of copper.

    PubMed

    Navel, Aline; Martins, Jean M F

    2014-01-01

    In this study we evaluated the effect of the long term organic management of a vineyard-soil on the biogeochemistry of copper at the micro-aggregate scale. The model vineyard-soil (Mâcon-France) experienced a long-term field-experiment that consisted in amendments and vegetations with various materials and plants. We studied specifically the effect of Straw (S) and Conifer Compost (CC) organic amendments and Clover (Cl) and Fescue (F) vegetation on the fate of copper (fungicide) in the surface layer of this loamy soil, through a comparison with the Non Amended soil (NA). After collection the five soils were immediately physically fractionated in order to obtain 5 granulometric size-fractions. All soils and size-fractions were quantitatively characterized in terms of granulometry, chemical content and copper distribution, speciation and bioavailability to bacteria and plants. The results showed strong increases of soil-constituents aggregation for all treatments (Cl>CC>S>F>NA), in relation with the increased cementation of soil-constituents by organic matter (OM). The distribution patterns of all major elements and organic carbon were found highly variable within the soil sub-fractions and also between the 5 treatments. Due to their specific inorganic and organic composition, soil sub-fractions can thus be considered as a specific microbial habitat. Added OM accumulated preferentially in the 20-2 μm and in the >250 μm of the 5 soils. The distribution patterns of copper as well as its speciation and bioavailability to bacteria in the soil sub-fractions were shown to be strongly different among the five soils, in relation with OM distribution. Our results also suggest that Cu-bioavailability to plants is controlled by soil-rhizosphere structure. Altogether our results permitted to show that long-term organic management of a vineyard soil induced stable modifications of soil physical and chemical properties at both macro and micro-scales. These modifications

  5. Carbon flux from plants to soil microbes is highly sensitive to nitrogen addition and biochar amendment

    NASA Astrophysics Data System (ADS)

    Kaiser, C.; Solaiman, Z. M.; Kilburn, M. R.; Clode, P. L.; Fuchslueger, L.; Koranda, M.; Murphy, D. V.

    2012-04-01

    The release of carbon through plant roots to the soil has been recognized as a governing factor for soil microbial community composition and decomposition processes, constituting an important control for ecosystem biogeochemical cycles. Moreover, there is increasing awareness that the flux of recently assimilated carbon from plants to the soil may regulate ecosystem response to environmental change, as the rate of the plant-soil carbon transfer will likely be affected by increased plant C assimilation caused by increasing atmospheric CO2 levels. What has received less attention so far is how sensitive the plant-soil C transfer would be to possible regulations coming from belowground, such as soil N addition or microbial community changes resulting from anthropogenic inputs such as biochar amendments. In this study we investigated the size, rate and sensitivity of the transfer of recently assimilated plant C through the root-soil-mycorrhiza-microbial continuum. Wheat plants associated with arbuscular mycorrhizal fungi were grown in split-boxes which were filled either with soil or a soil-biochar mixture. Each split-box consisted of two compartments separated by a membrane which was penetrable for mycorrhizal hyphae but not for roots. Wheat plants were only grown in one compartment while the other compartment served as an extended soil volume which was only accessible by mycorrhizal hyphae associated with the plant roots. After plants were grown for four weeks we used a double-labeling approach with 13C and 15N in order to investigate interactions between C and N flows in the plant-soil-microorganism system. Plants were subjected to an enriched 13CO2 atmosphere for 8 hours during which 15NH4 was added to a subset of split-boxes to either the root-containing or the root-free compartment. Both, 13C and 15N fluxes through the plant-soil continuum were monitored over 24 hours by stable isotope methods (13C phospho-lipid fatty acids by GC-IRMS, 15N/13C in bulk plant

  6. Polybrominated diphenyl ether (PBDE) accumulation by earthworms (Eisenia fetida) exposed to biosolids-, polyurethane foam microparticle-, and Penta-BDE-amended soils.

    PubMed

    Gaylor, Michael O; Harvey, Ellen; Hale, Robert C

    2013-12-03

    Polybrominated diphenyl ether (PBDE) flame retardants have been used in consumer polymers at up to percent levels. While long viewed as biologically inaccessible therein, PBDEs may become bioaccessible following volatilization or polymer deterioration. PBDEs may then enter soils via polymer fragmentation or following land application of sewage sludge-derived biosolids. Studies of direct PBDE uptake from these materials by soil organisms are scarce. We thus exposed earthworms ( Eisenia fetida ) to artificial soil amended with a Class B anaerobically digested biosolid (ADB), an exceptional quality composted biosolid (CB), PBDE-containing polyurethane foam (PUF) microparticles, and Penta-BDE-spiked artificial soil (SAS). Worms accumulated mg/kg (lipid) ∑Penta-PBDE burdens from all substrates. Biota-soil accumulation factors (BSAFs) for worms exposed to ADB- and CB-amended soils were comparable after 28 d. BSAFs generally decreased with increasing congener KOW and substrate dosage. Biosolids-associated PBDE bioavailability was lower than spiked PBDEs. BSAFs for worms exposed to PUF microparticles ranged from 3.9 to 33.4, with ∑Penta-PBDE tissue burdens reaching 3740 mg/kg lipid. Congener accumulation patterns were similar in worms and polyethylene passive sampling devices immersed in ADB-amended soil coincident with exposed worms. However, passive sampler accumulation factors were lower than BSAFs. Our results demonstrate that PBDEs may accumulate in organisms ingesting soils containing biosolids or waste plastics. Such organisms may then transfer their burdens to predators or translocate them from the site of application/disposal.

  7. Solubility of lead and copper in biochar-amended small arms range soils: influence of soil organic carbon and pH

    USDA-ARS?s Scientific Manuscript database

    In situ application of heavy metal stabilizing agents has in some cases increased the mobility of target metal contaminants. Mechanistic understandings are necessary to better predict (1) the dynamic short- and long-term response to soil amendments, and (2) the utility of biochars in nonremoval and...

  8. Conocarpus biochar as a soil amendment for reducing heavy metal availability and uptake by maize plants.

    PubMed

    Al-Wabel, Mohammad I; Usman, Adel R A; El-Naggar, Ahmed H; Aly, Anwar A; Ibrahim, Hesham M; Elmaghraby, Salem; Al-Omran, Abdulrasoul

    2015-07-01

    The objective of this study was to assess the use of Concarpus biochar as a soil amendment for reducing heavy metal accessibility and uptake by maize plants (Zea mays L.). The impacts of biochar rates (0.0, 1.0, 3.0, and 5.0% w/w) and two soil moisture levels (75% and 100% of field capacity, FC) on immobilization and availability of Fe, Mn, Zn, Cd, Cu and Pb to maize plants as well as its application effects on soil pH, EC, bulk density, and moisture content were evaluated using heavy metal-contaminated soil collected from mining area. The biochar addition significantly decreased the bulk density and increased moisture content of soil. Applying biochar significantly reduced NH4OAc- or AB-DTPA-extractable heavy metal concentrations of soils, indicating metal immobilization. Conocarpus biochar increased shoot dry biomass of maize plants by 54.5-102% at 75% FC and 133-266% at 100% FC. Moreover, applying biochar significantly reduced shoot heavy metal concentrations in maize plants (except for Fe at 75% FC) in response to increasing application rates, with a highest decrease of 51.3% and 60.5% for Mn, 28% and 21.2% for Zn, 60% and 29.5% for Cu, 53.2% and 47.2% for Cd at soil moisture levels of 75% FC and 100% FC, respectively. The results suggest that biochar may be effectively used as a soil amendment for heavy metal immobilization and in reducing its phytotoxicity.

  9. Conocarpus biochar as a soil amendment for reducing heavy metal availability and uptake by maize plants

    PubMed Central

    Al-Wabel, Mohammad I.; Usman, Adel R.A.; El-Naggar, Ahmed H.; Aly, Anwar A.; Ibrahim, Hesham M.; Elmaghraby, Salem; Al-Omran, Abdulrasoul

    2014-01-01

    The objective of this study was to assess the use of Concarpus biochar as a soil amendment for reducing heavy metal accessibility and uptake by maize plants (Zea mays L.). The impacts of biochar rates (0.0, 1.0, 3.0, and 5.0% w/w) and two soil moisture levels (75% and 100% of field capacity, FC) on immobilization and availability of Fe, Mn, Zn, Cd, Cu and Pb to maize plants as well as its application effects on soil pH, EC, bulk density, and moisture content were evaluated using heavy metal-contaminated soil collected from mining area. The biochar addition significantly decreased the bulk density and increased moisture content of soil. Applying biochar significantly reduced NH4OAc- or AB-DTPA-extractable heavy metal concentrations of soils, indicating metal immobilization. Conocarpus biochar increased shoot dry biomass of maize plants by 54.5–102% at 75% FC and 133–266% at 100% FC. Moreover, applying biochar significantly reduced shoot heavy metal concentrations in maize plants (except for Fe at 75% FC) in response to increasing application rates, with a highest decrease of 51.3% and 60.5% for Mn, 28% and 21.2% for Zn, 60% and 29.5% for Cu, 53.2% and 47.2% for Cd at soil moisture levels of 75% FC and 100% FC, respectively. The results suggest that biochar may be effectively used as a soil amendment for heavy metal immobilization and in reducing its phytotoxicity. PMID:26150758

  10. Leaching of Clothianidin in Two Different Indian Soils: Effect of Organic Amendment.

    PubMed

    Singh, Ningthoujam Samarendra; Mukherjee, Irani; Das, Shaon Kumar; Varghese, E

    2018-04-01

    Clothianidin is a widely used insecticide under Indian subtropical condition. The objective of this study was to generate residue data which aims to understand leaching potential of clothianidin [(E)-1-(2-chloro-1,3-thiazol-5-ylmethyl)-3-methyl-2- nitroguanidine] through packed soil column. The maximum amount of clothianidin was recovered at 0-5 cm soil depth in both Manipur (67.15%) and Delhi soil (52.0%) under continuous flow condition. Manipur and Delhi soil concentrated maximum residue with or without farm yard manure (FYM) in 0-20 cm soil depth. The effect of varying the amount of water enhanced the distribution of residues in the first 0-5 cm layer. Among the tested soils, residue was detected in the leachate from Delhi soil (0.04 µg/mL). Clothianidin leaching was minimized in soil of Manipur compared to Delhi after incorporation of FYM. As the volume of water increased upto 160 mL, mobility increased and residues moved to lower depth. Clothianidin did not leach out of the 25 cm long soil columns even after percolating water equivalent to 415.42 mm rainfall. Clothianidin is mobile in soil system and mobility can be reduced by organic amendment application.

  11. Microbial effects on two tropical soils amended with different types of biochar

    NASA Astrophysics Data System (ADS)

    Paz, Jorge; Méndez, Ana; Fun, Shenglei; Gascó, Gabriel

    2013-04-01

    There is an increasing interest in using biochar as soil amendment due to its potential to reduce greenhouse gas emissions from soils and to mitigate heavy metal pollution. In addition, sometimes biochar has been found to increase soil productivity due to its favourable effect on soil aggregation and water holding capacity. However, results obtained can differ greatly depending on the type of biochar utilised. On the other hand, the response of the microbial community to biochar addition is not so well understood. In our experiment we have sampled two soils, differing in their fertility status. A greenhouse pot experiment was established to see the effect of adding four different biochars, differing on their feedstock (Miscanthus, sewage sludge, paper mill waste and pinewood). Additionally, half of the samples excluded soil earthworms, while the other half had 3 individuals of the earthworm Pontoscolex corethrurus. Pots, containing 400 g of soil, were planted with proso millet. Assessed parameters included millet height, soil microbial biomass and soil enzymatic activity related to different biogeochemical cycles (invertase, B-glucosaminidase, B-glucosidase, urease, phosphomonoesterase, arylsulphatase) The effects of biochar on soil biological properties depended on the type of feedstock used for biochar production and pre-existent soil parameters such as soil fertility status. Earthworm presence generally had a positive effect on soil microbial properties.

  12. Groundwater pollution potential and greenhouse gas emission from soils amended with different swine biochars

    USDA-ARS?s Scientific Manuscript database

    Although there exist numerous research studies in the literature on greenhouse gas emission and groundwater pollution potentials of soils amended with plant-based biochar made from traditional dry pyrolysis (hereafter referred as pyrochar), a very few such studies exist for hydrochar made from hydro...

  13. Development of an analytical procedure to study linear alkylbenzenesulphonate (LAS) degradation in sewage sludge-amended soils.

    PubMed

    Comellas, L; Portillo, J L; Vaquero, M T

    1993-12-24

    A procedure for determining linear alkylbenzenesulphonates (LASs) in sewage sludge and amended soils has been developed. Extraction by sample treatment with 0.5 M potassium hydroxide in methanol and reflux was compared with a previously described extraction procedure in Soxhlet with methanol and solid sodium hydroxide in the sample. Repeatability results were similar with savings in extraction time, solvents and evaporation time. A clean-up method involving a C18 cartridge has been developed. Analytes were quantified by a reversed-phase HPLC method with UV and fluorescence detectors. Recoveries obtained were higher than 84%. The standing procedure was applied to high doses of sewage sludge-amended soils (15%) with increasing quantities of added LASs. Degradation data for a 116-day period are presented.

  14. Effect of immobilized rhizobacteria and organic amendment in bulk and rhizospheric soil of Cistus albidus L.

    NASA Astrophysics Data System (ADS)

    Mengual, Carmen Maria; del Mar Alguacil, Maria; Roldan, Antonio; Schoebitz, Mauricio

    2013-04-01

    A field experiment was carried out to assess the effectiveness of the immobilized microbial inoculant and the addition of organic olive residue. The microbial inoculant contained two rhizobacterial species identified as Azospirillum brasilense and Pantoea dispersa immobilized in a natural inert support. Bacterial population densities were 3.5×109 and 4.1×109 CFU g-1 of A. brasilense M3 and P. dispersa C3, respectively. The amendment used was the organic fraction extracted with KOH from composted "alperujo". The raw material was collected from an olive-mill and mixed with fresh cow bedding as bulking agent for composting. The inoculation of rhizobacteria and the addition of organic residue were employed for plant growth promotion of Cistus albidus L. and enhancement of soil physicochemical, biochemical and biological properties in a degraded semiarid Mediterranean area. One year after planting, the available phosphorus and potassium content in the amended soils was about 100 and 70% respectively higher than in the non-amended soil. Microbial inoculant and their interaction with organic residue increased the aggregate stability of the rhizosphere soil of C. albidus (by 12% with respect to control soil) while the organic residue alone not increased the aggregate stability of the rhizosphere of C. albidus. Microbial biomass C content and enzyme activities (dehydrogenase, urease, protease-BAA and alkaline phosphatase) of the rhizosphere of C. albidus were increased by microbial inoculant and organic residue interaction but not by microbial inoculation alone. The microbial inoculant and organic residue interaction were the most effective treatment for stimulating the roots dry weight of C. albidus (by 133% with respect to control plants) and microbial inoculant was the most effective treatment for increase the shoot dry weigh of plants (by 106% with respect to control plants). The combined treatment, involving microbial inoculant and addition of the organic residue

  15. Effect of inoculant strain and organic matter content on kinetics of 2,4-dichlorophenoxyacetic acid degradation in soil.

    PubMed

    Greer, L E; Shelton, D R

    1992-05-01

    We monitored rates of degradation of soluble and sorbed 2,4-dichlorophenoxyacetic acid (2,4-D) in low-organic-matter soil at field capacity amended with 1, 10, or 100 micrograms of 2,4-D per g of wet soil and inoculated with one of two bacterial strains (MI and 155) with similar maximum growth rates (mu max) but significantly different half-saturation growth constants (Ks). Concentrations of soluble 2,4-D were determined by analyzing samples of pore water pressed from soil, and concentrations of sorbed 2,4-D were determined by solvent extraction. Between 65 and 75% of the total 2,4-D was present in the soluble phase at equilibrium, resulting in soil solution concentrations of ca. 8, 60, and 600 micrograms of 2,4-D per ml, respectively. Soluble 2,4-D was metabolized preferentially; this was followed by degradation of both sorbed (after desorption) and soluble 2,4-D. Rates of degradation were comparable for the two strains at soil concentrations of 10 and 100 micrograms of 2,4-D per g; however, at 1 microgram/g of soil, 2,4-D was metabolized more rapidly by the strain with the lower Ks value (strain MI). We also monitored rates of biodegradation of soluble and sorbed 2,4-D in high-organic-matter soil at field capacity amended with 100 micrograms of 2,4-D per g of wet soil and inoculated with the low-Ks strain (strain MI). Ten percent of total 2,4-D was present in the soluble phase, resulting in a soil solution concentration of ca. 30 micrograms of 2,4-D per ml.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Use of insoluble polyacrylate polymers to aid phytostabilization of mine soils: effects on plant growth and soil characteristics.

    PubMed

    Qu, G; de Varennes, A; Cunha-Queda, C

    2010-01-01

    We evaluated the use of polyacrylate polymers to aid phytostabilization of mine soils. In a pot experiment, perennial ryegrass was grown in a mine soil and in uncontaminated soil. Growth was stimulated in the polymer-amended mine soil compared with an unamended control, and water-extractable levels of soil Cu and Zn decreased after polymer application. In an experiment performed in six 60-cm-diameter cylinders filled with fertilized mine soil, polymers were applied to three cylinders, with the remainder used as unamended control. Total biomass produced by indigenous plant species sown in polymer-amended soil was 1.8 (Spring-Summer) or 2.4 times (Fall-Winter) greater than that of plants from unamended soil. The application of polymers to the mine soil led to the greatest activity of soil enzymes. Soil pH, biomass of Spergularia purpurea and Chaetopogon fasciculatus, and activities of protease and cellulase had large loadings on principal component (PC)1, whereas growth of Briza maxima and the activities of urease, acid phosphatase, and beta-glucosidase had large loadings on PC2. The treatments corresponding to controls were located on the negative side of PC1 and PC2. Amended treatments were on the positive side of PC2 (Spring-Summer) or on the positive side of PC1 (Fall-Winter), demonstrating differential responses of plants and soil parameters in the two growth cycles.

  17. [Amelioration effects of wastewater sludge biochars on red soil acidity and their environmental risk].

    PubMed

    Lu, Zai-Liang; Li, Jiu-Yu; Jiang, Jun; Xu, Ren-Kou

    2012-10-01

    the corresponding sludge from Chengdong wastewater treatment plant for most of heavy metals. It can be concluded that the biochars from wastewater sludge could be used as soil amendments to adjust soil acidity. Application of sludge biochars did not increase activity and availability of heavy metals compared with direct incorporation of the sludge.

  18. Anaerobic soil disinfestation: Carbon rate effects on tomato plant growth and organic acid production

    USDA-ARS?s Scientific Manuscript database

    Anaerobic soil disinfestation (ASD) is a non-chemical soil disinfestation technique proposed for the control of soil-borne pathogens, plant parasitic-nematodes, and weeds in different crops. ASD is applied in three steps: 1) Soil amendment with a labile carbon (C) source; 2) Cover the soil with tota...

  19. Field dissipation and risk assessment of typical personal care products TCC, TCS, AHTN and HHCB in biosolid-amended soils.

    PubMed

    Chen, Feng; Ying, Guang-Guo; Ma, Yi-Bing; Chen, Zhi-Feng; Lai, Hua-Jie; Peng, Feng-Jiao

    2014-02-01

    The antimicrobial agents triclocarban (TCC) and triclosan (TCS) and synthetic musks AHTN (Tonalide) and HHCB (Galaxolide) are widely used in many personal care products. These compounds may release into the soil environment through biosolid application to agricultural land and potentially affect soil organisms. This paper aimed to investigate accumulation, dissipation and potential risks of TCC, TCS, AHTN and HHCB in biosolid-amended soils of the three field trial sites (Zhejiang, Hunan and Shandong) with three treatments (CK: control without biosolid application, T1: single biosolid application, T2: repeated biosolid application every year). The one-year monitoring results showed that biosolids application could lead to accumulation of these four chemicals in the biosolid-amended soils, with the residual concentrations in the following order: TCC>TCS>AHTN>HHCB. Dissipation of TCC, TCS, AHTN and HHCB in the biosolid-amended soils followed the first-order kinetics model. Half-lives for TCC, TCS, AHTN and HHCB under the field conditions of Shandong site were 191, 258, 336 and 900 days for T1, and 51, 106, 159 and 83 days for T2, respectively. Repeated applications of biosolid led to accumulation of these personal care products and result in higher ecological risks. Based on the residual levels in the trial sites and limited toxicity data, high risks to soil organisms are expected for TCC and TCS, while low-medium risks for AHTN and HHCB. © 2013.

  20. Organic amendments and mulches influence the quality of restored mine soils and plant cover in semiarid regions.

    NASA Astrophysics Data System (ADS)

    Luna Ramos, Lourdes; Miralles, Isabel; Contreras, Sergio; Lázaro-Suau, Roberto; Solé-Benet, Albert

    2017-04-01

    An experimental restoration was designed in a calcareous quarry in Sierra de Gádor, SE Spain, with the aim of determining useful semiarid restoration techniques. The factors tested were: a) organic amendments (sewage sludge, compost and no amendment), b) mulches (gravel, woodchip and no mulch), and c) three native species (Macrochloa tenacissima, Anthyllis terniflora and Anthyllis cytisoides). Nine combinations of organic amendments and mulches were established in plots of 15 x 5 m and 75 plants were planted in each plot. Plant survival and growth were measured at months 6, 24, 36 and 48 after planting. Moreover, the possible relationships between soil quality indicators (physico-chemical and microbiological properties, aggregate stability and infiltration rate) and changes in the planted vegetation caused by restoration treatments were explored. This study demonstrated that opencast mine revegetation with native species (M. tenacissima, A. terniflora and A. cytisoides) was successful in the boundary between arid and semiarid climate in only four years, compared to previous soil restoration treatment. The response of plant species was different, showing their own physiological mechanisms. M. tenacissima presented the highest survival rates although the two Anthyllis species had the highest growth rates. Despite organic amendments had not a positive effect on plant survival, these treatments increased plant growth. In particular, the improvement on chemical, microbiological and physical soil properties induced by sewage sludge and especially compost treatment, enhanced plant growth. However, changes induced by mulches on the physico-chemical soil properties did not provided clear evidences, either positive or negative, in plant establishment. Thus, the addition of organic matter from organic residues and revegetation with native species can improve the restoration success in SE Spain and perhaps similar regions worldwide under arid-semiarid climate.