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Sample records for acid sulphate soils

  1. The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils.

    PubMed

    Šimek, Miloslav; Virtanen, Seija; Simojoki, Asko; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, Markku

    2014-01-01

    Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg Cg(-1)h(-1), as compared to 2.71 μg Cg(-1)h(-1) in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng Ng(-1)d(-1)). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming.

  2. Alleviating aluminium toxicity on an acid sulphate soils in Peninsular Malaysia with application of calcium silicate

    NASA Astrophysics Data System (ADS)

    Elisa, A. A.; Ninomiya, S.; Shamshuddin, J.; Roslan, I.

    2015-10-01

    A study was conducted to alleviate Al toxicity of an acid sulphate soils collected from paddy cultivation area in Kedah, Peninsular Malaysia. For this purpose, the collected acid sulphate soils were treated with calcium silicate. The treated soils were incubated for 120 days in submerged condition in a glasshouse. Subsamples were collected every 30 days throughout the incubation period. Soil pH and exchangeable Al showed positive effect; soil pH increased from 2.9 to 3.5, meanwhile exchangeable Al was reduced from 4.26 to 0.82 cmolc kg-1, which was well below the critical Al toxicity level for rice growth of 2 cmolc kg-1. It was noted that the dissolution of calcium silicate (CaSiO3) supplied substantial amount of Ca2+ and H4SiO42- ions into the soil, noted with increment in Si (silicate) content from 21.21 to 40 mg kg-1 at day 30 and reduction of exchangeable Al at day 90 from 4.26 to below 2 cmolc kg-1. During the first 60 days of incubation, Si content was positively correlated with soil pH, while the exchangeable Al was negatively correlated with Si content. It is believed that the silicate anions released by calcium silicate were active in neutralizing H+ ions that governs the high acidity (pH 2.90) of the acid sulphate soils. This scenario shows positive effect of calcium silicate to reduce soil acidity, therefore creates a favourable soil condition for good rice growth during its vegetative phase (30 days). Thus, application of calcium silicate to alleviate Al toxicity of acid sulphate soils for rice cultivation is a good soil amendment.

  3. Laboratory Study of Methane Flux from Acid Sulphate Soil in South Kalimantan

    NASA Astrophysics Data System (ADS)

    Annisa, W.; Cahyana, D.; Syahbuddin, H.; Rachman, A.

    2017-06-01

    Addition of organic matter in waterlogged conditions will enhance methanogenesis process that produces greenhouse gases. Fresh organic material is considered reactive because it contains carbons that is subject to decompose, therefore, when it exposed to acid sulphate soil, both in natural condition (aeration required) and intensive (aeration not required) will lower the value of redox potential. This experiment aimed to determine the flux of methane (CH4) from various locally available organic materials applied to acid sulphate soil. The experiment was arranged in factorial design with two factors. The first factor was the source of organic matter, i.e. fresh rice straw, fresh purun, fresh cattle manure, composted rice straw, composted purun and composted cattle manure, and control. The second factor was the management of organic matter i.e. placed on the soil surface with no tillage and mixed with soil during tillage. The results showed that application of fresh organic matter into inundated acid sulphate soil increased CH4 fluxes up to 23.78 µg CH4 g1 d1 which was higher than from composted organic matter (4.327 µg CH4.g1.d1). Methane flux due to organic matter management was significantly negatively (p=0.001) correlated with soil redox potential (Eh) with R2 of - 0.76. Organic matter placed on the soil surface with no tillage produced methane flux ranged from 0.33 to 20.78 g CH4 g1 d1, which was lower than methane flux produced from organic matter mixed with soil during tillage (0.38 to 27.27 g CH4 g1 d1). Composting organic matter before application and mixing them with the soil through tillage are highly recommended to reduce greenhouse gas emissions from cultivated acid sulphate soils.

  4. 1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag

    PubMed Central

    Islam, Shahidul; Haque, Asadul; Bui, Ha Hong

    2016-01-01

    Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS) cured up to 365 days. The void ratio-logarithm of pressure (e-logσ′) behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis. PMID:28773415

  5. Estuarine behaviour of metal loads leached from coastal lowland acid sulphate soils.

    PubMed

    Nordmyr, Linda; Osterholm, Peter; Aström, Mats

    2008-09-01

    The estuarine behaviour of the metal load leaching from acid sulphate (AS) soils was studied in a selected river system (the Vörå River), in western Finland. Large amounts of metals were transported with the river and deposited within the estuary, causing highly elevated metal concentrations in both the sediment traps and in the underlying bottom sediments. Among the metals, there was a diverging deposition pattern where Al, Cu, La and U demonstrated a strong association with organic matter and were deposited within approximately 4 km from the river mouth. In contrast, the deposition of Co, Mn, Ni and Zn occurred when pH reached circumneutral conditions further out in the estuary. Yet other metals were not abundantly leached from the AS soils and thus not elevated in the river and estuary (Fe, Ti, Cr, V). Five separate chemical extractions indicated the geochemical speciation of the metals.

  6. Al-Fe interactions and growth enhancement in Melastoma malabathricum and Miscanthus sinensis dominating acid sulphate soils.

    PubMed

    Watanabe, Toshihiro; Jansen, Steven; Osaki, Mitsuru

    2006-12-01

    Plants growing in acid sulphate soils are subject to high levels of Al availability, which may have effects on the growth and distribution of these species. Although Fe availability is also high in acid sulphate soils, little is known about the effect of Fe on the growth of native plants in these soils. Two species dominating this soil type in Asia, viz. Melastoma malabathricum and Miscanthus sinensis were grown hydroponically in a nutrient solution with different concentrations of Al and Fe. Melastoma malabathricum is found to be sensitive to Fe (40 and 100 microm). Application of 500 microm Al, however, completely ameliorates Fe toxicity and is associated with a decrease of Fe concentration in shoots and roots. The primary reason for the Al-induced growth enhancement of M. malabathricum is considered to be the Al-induced reduction of toxic Fe accumulation in roots and shoots. Therefore, Al is nearly essential for M. malabathricum when growing in acid sulphate soils. In contrast, application of both Fe and Al does not reduce the growth of M. sinensis, and Al application does not result in lower shoot concentrations of Fe, suggesting that this grass species has developed different mechanisms for adaptation to acid sulphate soils.

  7. Metal pollution of estuarine sediments caused by leaching of acid sulphate soils

    NASA Astrophysics Data System (ADS)

    Nordmyr, Linda; Åström, Mats; Peltola, Pasi

    2008-01-01

    This study tracks changes in metal distribution in estuarine sediments as a result of leakage from acid sulphate (AS) soil landscapes in the Boreal Zone (Finland). The main objective was to identify the impact of these nasty soils on sediment geochemistry in a biologically sensitive and shallow brackish-water estuary. In order to do this four sediment cores were sampled in a profile extending seawards from the mouth of the Vörå River, which is one of the most heavily AS soil-impacted rivers in Finland and Europe. Two of the cores were rather deep (2.5 m and 4.0 m) and the others were shallow (0.4 m and 0.8 m). The results showed that an appreciable amount of aluminium (Al), cobalt (Co), cadmium (Cd), copper (Cu), manganese (Mn), nickel (Ni) and zinc (Zn) were elevated in the surface and sub-surface of the sampled bottom sediments compared to the deeper sediment background levels. These metals are all known to be abundantly leached from the AS soils. At the site approximately 4 km away from the river mouth, the concentrations of Cd, Co, Mn, Ni and Zn were elevated 5-100 times as compared to the background levels and showed an intriguing cyclic pattern, most likely reflecting seasonal leaching dynamics in the AS soil landscapes. In contrast, metals that are not abundantly leached from AS soils, i.e. chromium (Cr), iron (Fe) and vanadium (V) had consistently low concentrations throughout all sediment cores. The elevated metal concentrations in the top layers of the sediments in the estuary are alarming. The continuous land uplift of the region combined with the episodic rapid declines in pH may result in short and long term extensive release of metals. This, in turn, may have significant effects on the trace-metal contents in the Gulf of Bothnia and the entire Baltic Sea.

  8. Radon tracing of groundwater discharge into an Australian estuary surrounded by coastal acid sulphate soils

    NASA Astrophysics Data System (ADS)

    Santos, Isaac R.; Eyre, Bradley D.

    2011-01-01

    SummaryWidespread sulphidic deposits have accumulated in tropical coastal floodplains throughout the world. Sulphidic soils oxidize when floodplains are drained for urban and agricultural development. As a result, large amounts of sulphuric acid may be released to nearby waterways. Macropores may create excellent conditions for groundwater flow in coastal acid sulphate soils (CASS). An automated radon ( 222Rn) measurement system was used to quantify groundwater inputs into a tidally-dominated estuary that is known to be influenced by acid discharges from CASS (Richmond River Estuary, Australia). A high resolution radon survey along a 120-km long segment of the tidal river identified two areas of preferential groundwater inputs. Intensive time series measurements in one of those areas (the Tuckean Broadwater) demonstrated that groundwater inputs are highly variable over hourly and seasonal time scales and inversely related to surface water pH. Elevated radon concentrations (up to 12 dpm/L) and low pH (as low as 3.3) were observed in surface waters at low tide a few weeks after a large rain event. These results demonstrate that acidic waters are entering the estuary via tidally-modulated groundwater flow pathways. Groundwater discharge rates into drains in the Tuckean Swamp were estimated from a dual-assumption radon mass balance to be 0.09-0.16 and 0.56-0.89 m 3 s -1 during the dry and wet season, respectively (or 6-10 and 37-59 cm/day if the area is taken into account). While surface runoff increased only 2-fold in the wet season relative to the dry season, groundwater discharge rates increased ˜6-fold. Since groundwater can be a major driver of surface water quality, radon can be useful in CASS monitoring and management efforts.

  9. Acid sulphate soil disturbance and metals in groundwater: implications for human exposure through home grown produce.

    PubMed

    Hinwood, Andrea Lee; Horwitz, Pierre; Appleyard, Steve; Barton, Caroline; Wajrak, Magda

    2006-09-01

    A significant emerging environmental problem is the disturbance and oxidation of soils with high levels of iron sulphide minerals resulting in acidification and causing the mobilization of metals into groundwater. This process is occurring in many parts of the world. In Western Australia, impacted groundwater is extracted by residents for domestic use. We sought to establish domestic use patterns of bore water and the concentration of metals. Sixty-seven domestic bore water samples clearly indicated oxidation of sulphidic materials with heavy metal concentrations ranging for aluminium (acid sulphate soil disturbance in many locations.

  10. The use of drilling solid waste as amendment of acid-sulphate soils of the Orinoco Delta

    SciTech Connect

    Vasquez, P.; Urich, J.; Gonzalez, V.

    1996-12-31

    The Venezuelan oil industry has begun an exploration and drilling program in the Orinoco Delta, and an intensive research is executed about the feasibility of landspreading as an option to dispose water based drilling wastes (DW) to avoid the contamination of water bodies. The original fluvial marine seasonal floodplain nearby Boca de Uracoa town (9{degrees}N, 62{degrees}, 21{degrees} W), was modified after the closure of Manamo distributary, which led to the transformation of the original substrate with high pyrite contain, to acid-sulphate soils. Greenhouse experiments were carried out applying Drilling Waste (DW) equivalent doses of 0, 200, 500, 1000 and 1500 m3/ha to an acid-sulphate soil, using as test plant Zea mays var. PB-8. The results show that the elevated pH of DW (pH of 9.7) neutralizes the very acidic reaction of the acid-sulphate soils (pH 2.85) which is reflected on the higher production of biomass obtained with DW equivalent doses over 500 m3/ha. The Ba content in aerial biomass was below 0.2 {mu}g/g in all treatments, while Pb and Zn content were depleted by the parallel application of Phosphoric rock (PR). Concentrations of these elements in the soil equilibrium solution, shows very low leaching and low availability for vegetation.

  11. Distribution and diversity of bacterial communities and sulphate-reducing bacteria in a paddy soil irrigated with acid mine drainage.

    PubMed

    Wang, H; Guo, C L; Yang, C F; Lu, G N; Chen, M Q; Dang, Z

    2016-07-01

    To investigate the effects of long-term acid mine drainage (AMD) irrigation on the change in bacterial community and sulphate-reducing bacteria (SRB) in a paddy soil. The bacterial community structures were investigated using 454 pyrosequencing, and 98 931 effective sequences were selected for the bacterial diversity analysis. The known dominant phyla in the paddy soil were Acidobacteria (33·5%), Proteobacteria (19·7%), Nitrospira (2·8%) and Actinobacteria (2·7%). Higher percentage of Acidobacteria than Proteobacteria was detected. The relative abundances of the dominant bacterial lineages were more significantly correlated with the soil pH, the organic matter and the sulphate than the heavy metals. The diversity of the SRB in the surface paddy soil showed that the uncultured SRB groups might play important roles in paddy soils. The other OTUs mainly belonged to six phylogenetic divisions: Desulfobacca, Desulfovibrio, Syntrophobacter, Desulforhopalus, Desulfarculus and Desulfobulbus. The distribution of the absolute abundance and the relative contribution of the SRB along the vertical soil profile were investigated by RT-PCR assays based on the dsrB gene. The abundance of the dsrB gene copy numbers was up to 1·92 × 10(9)  copies g(-1) dry soil, which is slightly higher than the other non-AMD-affected paddy soil. This study demonstrated that the abundance of SRB is increased by the AMD irrigation while changing the composition and diversity of the bacterial community in the paddy soil. This is, to our knowledge, the first attempt to characterize and quantify changes in the diversity and distribution of the microbial community and SRB in the long-term AMD-irrigated paddy soil, which will further increase our understanding of the impact of AMD on sulphur biogeochemical cycling in the paddy soil. © 2016 The Society for Applied Microbiology.

  12. Response of pore water Al, Fe and S concentrations to waterlogging in a boreal acid sulphate soil.

    PubMed

    Virtanen, Seija; Simojoki, Asko; Hartikainen, Helinä; Yli-Halla, Markku

    2014-07-01

    Environmental hazards caused by acid sulphate (AS) soils are of worldwide concern. Among various mitigation measures, waterlogging has mainly been studied in subtropical and tropical conditions. To assess the environmental relevance of waterlogging as a mitigation option in boreal AS soils, we arranged a 2.5-year experiment with monolithic lysimeters to monitor changes in the soil redox potential, pH and the concentrations of aluminium (Al), iron (Fe) and sulphur (S) in pore water in response to low and high groundwater levels in four AS soil horizons. The monoliths consisted of acidic oxidized B horizons and a reduced C horizon containing sulphidic material. Eight lysimeters were cropped (reed canary grass, Phalaris arundinacea) and two were bare without a crop. Waterlogging was conducive to reduction reactions causing a slight rise in pH, a substantial increase in Fe (Fepw) and a decrease in Al (Alpw) in the pore water. The increase in Fepw was decisively higher in the cropped waterlogged lysimeters than in the bare ones, which was attributable to the microbiologically catalysed reductive dissolution of poorly ordered iron oxides and secondary minerals. In contrast to warmer climates, Fepw concentrations remained high throughout the experiment, indicating that the reduction was poised in the iron range, while sulphate was not reduced to sulphide. Therefore, the precipitation of iron sulphide was negligible in the environment with a low pH and abundant with poorly ordered Fe oxides. Increased Fe in pore water counteracts the positive effects of waterlogging, when water is flushed from fields to watercourses, where re-oxidation of Fe causes acidity and oxygen depletion. However, waterlogging prevented further oxidation of sulphidic materials and decreased Alpw to one-tenth of the initial concentrations, and even to one-hundredth of the levels in the low water table lysimeters.

  13. A multi-scale comparison of dissolved Al, Fe and S in a boreal acid sulphate soil.

    PubMed

    Virtanen, Seija; Simojoki, Asko; Rita, Hannu; Toivonen, Janne; Hartikainen, Helinä; Yli-Halla, Markku

    2014-11-15

    Acid sulphate (AS) soils are most prevalent in the tropics, but the acidic discharge from cultivated AS soils also threatens water bodies under boreal conditions. Feasible options to reduce the acid load are needed. In this study, the groundwater of an AS field was monitored for 3.5 years, and the efficiency of waterlogging in mitigating the environmental risks caused by acidic discharge was investigated in a 2.5-year experiment with 10 monolithic lysimeters taken from the same field. In order to unravel the transferability of the results from lysimeters to the field scale, the Al, Fe and S concentrations in discharge water from the lysimeters were compared with those in the groundwater of the AS field (pedon and field scale), and in pore water (pedon and horizon scale). In the waterlogged bare lysimeters (HWB), the Al, Fe and S concentrations in discharge waters were broadly similar to those measured in the groundwater and followed the changes in the pore water. In the waterlogged cropped (reed canary grass, Phalaris arundinacea) lysimeters (HWC), in contrast, the discharge waters were markedly higher in Fe and lower in Al than the groundwater in the field. This outcome was attributable to the reduction of Fe(3+) to the more soluble Fe(2+) and the reduction-induced increase in pH, which enhanced the formation of Al(3+) hydroxy species. Lowering of the water table (LWC) caused soil ripening, which resulted in increased saturated hydraulic conductivity and porosity and enhanced the oxidation of sulphidic materials and acid formation. The responses of Al, Fe and S in drainage waters from HWC and LWC lysimeters resembled previous findings in AS soils. Based on this and the similarity between dissolved element concentrations in the discharge water of HWB lysimeters and groundwater in the field, we conclude that our monolithic lysimeters yielded realistic results concerning the efficiency of various methods in mitigating environmental risks related to cultivated AS

  14. Distribution of rare earth elements in anionic, cationic and particulate fractions in boreal humus-rich streams affected by acid sulphate soils.

    PubMed

    Aström, Mats; Corin, Nina

    2003-01-01

    The abundance, fractionation and physicochemical forms of rare earth elements (REEs) were determined in five boreal humus-rich streams (dissolved organic carbon, DOC = 14-40 mg/l) affected by acid sulphate soils. The sampling was carried out during high-water flow in autumn when the acid sulphate soils are extensively flushed. The analytical procedures included ion-exchange experiments in field and ICP-MS determination. There was a general decrease in pH (range 4.5-6.2) and increase in the REE concentrations (La range 0.82-23 microg/l) as the proportion of the catchment cover of acid sulphate soils increased, explained by high amounts of REEs in the acidic runoff from such soils. In each stream, four different REE fractions were identified: (1) A cationic fraction, which is dominant in the REE-rich runoff from the acid sulphate soils and which is depleted in HREEs due to hydrochemical and/or geochemical processes, (2) an anionic fraction identified as humus-REE complexes, which in general is more abundant the higher the DOC concentrations and which also becomes increasingly abundant across the lanthanide series, (3) a fraction having a well-developed MREE enrichment, presumably consisting of colloidal REEs, and (4) a minor uncharacterised particle-associated fraction. The REE pool in the streams thus consists of several coexisting and contrasting REE species. The identification and quantification of such species is a prerequisite for the precise and accurate characterisation of the REE hydrochemistry of the streams.

  15. Toxicity of acid-sulphate soil leachate and aluminium to the embryos and larvae of Australian bass (Macquaria novemaculeata) in estuarine water.

    PubMed

    Hyne, R V; Wilson, S P

    1997-01-01

    The toxicity of leachate water from acid-sulphate soil to the early life stages of Australian bass, Macquaria novemaculeata, incubated in seawater was evaluated. Acid-sulphate soil leachate water (pH> or =6.8) delayed the hatching of fertilised eggs, but after 48 h the per cent hatching was normal. In comparison, acidic saline water (25 per thousand salinity) at pH 4.0 or less prevented embryos from hatching. The survival of yolk-sac larvae exposed to acid-sulphate soil leachate water at a concentration of 32% in seawater and an initial pH of 7.2, was significantly different to controls after 96 hours. In corresponding tests with only acidified saline water (20 per thousand salinity), pH levels equal to or below 5.0 killed yolk-sac larvae after 96 h exposure. Aluminum showed a pH dependent toxicity to yolk-sac larvae, with added aluminium as low as 200 microg litre(-1) having a significant effect on larval survival at pH 5.5, and concentrations of 600-800 microg litre(-1) having a significant effect on larval survival at an initial pH range of 6.0 < pH < 6.8. It was concluded that significant mortality of the early life stages of Australian bass would occur if they are exposed to acid-sulphate soil leachate that results in a pH in the receiving estuarine water below 5.5, or when the pH is below 6.8 and aluminium is present at a total concentration of 800 microg litre(-1) or greater.

  16. Organic materials retain high proportion of protons, iron and aluminium from acid sulphate soil drainage water with little subsequent release.

    PubMed

    Dang, Tan; Mosley, Luke M; Fitzpatrick, Rob; Marschner, Petra

    2016-12-01

    When previously oxidised acid sulphate soils are leached, they can release large amounts of protons and metals, which threaten the surrounding environment. To minimise the impact of the acidic leachate, protons and metals have to be retained before the drainage water reaches surrounding waterways. One possible amelioration strategy is to pass drainage water through permeable reactive barriers. The suitability of organic materials for such barriers was tested. Eight organic materials including two plant residues, compost and five biochars differing in feedstock and production temperature were finely ground and filled into PVC cores at 3.5 g dry wt/core. Field-collected acidic drainage water (pH 3, Al 22 mg L(-1) and Fe 48 mg L(-1)) was applied in six leaching events followed by six leaching events with reverse osmosis (RO) water (45 mL/event). Compost and biochars increased the leachate pH by up to 4.5 units and had a high retention capacity for metals. The metal and proton release during subsequent leaching with RO water was very small, cumulatively only 0.05-0.8 % of retained metals and protons. Retention was lower in the two plant residues, particularly wheat straw, which raised leachate pH by 2 units only in the first leaching event with drainage water, but had little effect on leachate pH in the following leaching events. It can be concluded that organic materials and particularly biochars and compost have the potential to be used in acid drainage treatment to remove and retain protons and metals.

  17. Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries.

    PubMed

    Wallin, Jaana; Karjalainen, Anna K; Schultz, Eija; Järvistö, Johanna; Leppänen, Matti; Vuori, Kari-Matti

    2015-03-01

    Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Sorption of endosulphan sulphate in soil organic matter.

    PubMed

    Chowdhury, Raja; Atwater, James W; Hall, Ken J; Parkinson, Paula

    2011-12-01

    Sorption of endosulphan sulphate in soil organic matter was investigated using Standard Elliot soil humic acid (HA) and soil fulvic acid (FA) at two ionic strengths (0.001 and 0.01). It was observed that divalent calcium ion and ionic strength affect the sorption of endosulphan sulphate in HA. All the experiments were carried out at pH 6.7 +/- 0.1. In the presence and absence of calcium (ionic strength 0.001), the solubility enhancement method was used to estimate the sorption coefficients of endosulphan sulphate in HA. For FA, the solubility enhancement method was used to estimate the sorption coefficients at an ionic strength of 0.001 (in the presence of calcium) and 0.01. The presence of calcium was found to significantly enhance (alpha = 0.01) the solubility of endosulphan sulphate in HA. Sorption coefficients at pH 6.7, obtained using the solubility enhancement method, were found to be 10-21 L/g in HA and 6 L/g in FA (in the presence of calcium). Increase in ionic strength from 0.001 to 0.01 decreased the sorption of endosulphan sulphate in HA. The effect of ionic strength and calcium on the sorption of endosulphan sulphate was most satisfactorily explained on the basis of the Donnan volume.

  19. Past and future seasonal variation in pH and metal concentrations in runoff from river basins on acid sulphate soils in Western Finland.

    PubMed

    Saarinen, Tuomas S; Kløve, Bjørn

    2012-01-01

    Drainage of acid sulphate soils (ASS) increases oxidation, leading to extensive leaching of acidity and metals to rivers (Al, Cd, Cr, Fe, Ni and Zn). This is often apparent during high runoff periods in spring and autumn after long dry periods with low groundwater levels and associated ASS oxidation. Regression models were used to study changes in these water quality variables according to various discharge scenarios. The knowledge of seasonal patterns of water quality variables in future is important for planning land use of the catchments in relation to WFD of European Union. The data showed that river water acidity (pH and metals) increased with discharge, with the correlation being strongest in low runoff periods in winter and summer and less clear in spring. With future climate change, river acidity can increase radically, especially during winters following extremely dry summers, and pH and metal peaks may occur even during winter.

  20. Sulphates Removal from Acid Mine Drainage

    NASA Astrophysics Data System (ADS)

    Luptáková, Alena; Mačingová, Eva; Kotuličová, Ingrida; Rudzanová, Dominika

    2016-10-01

    Acid mine drainage (AMD) are a worldwide problem leading to ecological destruction in river basins and the contamination of water sources. AMD are characterized by low pH and high content of heavy metals and sulphates. In order to minimize negative impacts of AMD appropriate treatment techniques has to be chosen. Treatment processes are focused on neutralizing, stabilizing and removing pollutants. From this reason efficient and environmental friendly methods are needed to be developed in order to reduce heavy metals as well as sulphates. Various methods are used for remediation of acid mine drainage, but any of them have been applied under commercial-scale conditions. Their application depends on geochemical, technical, natural, financial, and other factors. The aim of the present work was to interpret the study of biological methods for sulphates removal from AMD out-flowing from the shaft Pech of the deposit Smolmk in Slovak Republic. In the experimental works AMD were used after removal of heavy metals by precipitation and sorption using the synthetic sorbent Slovakite. The base of the studied method for the sulphates elimination was the anaerobic bacterial sulphate reduction using sulphate-reducing bacteria (SRB) genera Desulfovibrio. SRB represent a group of bacteria that uses sulphates as a terminal electron acceptor for their metabolism. These bacteria realize the conversion of sulphate to hydrogen sulphide under anaerobic conditions. For the purposes of experiments a few variants of the selective medium DSM-63 culture media were used in term of the sulphates and sodium lactate contents in the selective medium as well as sulphates in the studied AMD.

  1. Sulphate release from construction and demolition material in soils

    NASA Astrophysics Data System (ADS)

    Abel, Stefan; Wessolek, Gerd

    2013-04-01

    In Berlin and many other cities soils are heavily influenced by anthropogenic activities and deposited substrates. A widespread technical substrate in technosols is construction and demolition material from residential and industrial buildings. Existing rubble landfills without sealing facilities pose threats to ground water quality. In the central city of Berlin rising sulphate concentrations of groundwaters (up to 1200 mg/L) are measured since more than two decades. Previous studies point out that the high sulphate concentrations are mainly attributed to World War II rubble. The major part of debris was deposited in form of landfills and contains approximately 0.3 wt% gypsum. The scope of our research is to determine mechanisms of sulphate release from debris material, interactions between sulphate release, soil hydraulic properties and potential sinks of sulphur. To estimate equilibrium concentration and kinetics of sulphate release of various debris components batch and column experiments are conducted. The same method is applied to determine potential adsorptive character of common debris components. To analyse the impacts of soil hydraulic properties on sulphate leaching we carry out soil column experiments with defined upper and lower boundary conditions, varying water flow velocity and induced preferential flow. Simultaneously we monitor sulphate concentration of soil leachate in a 2 m³ lysimeter. First results of the batch experiments show that gypsum from broken stucco is the main source of sulphate in the observed technosols. Other components as mortar and slag show a quite low sulphate release. Similar results are found within the column experiments. For brigs medium and strongly time dependent sulphate release is determined. Concentrations up to 1500 mg/L are measured in the soil leachate from the lysimeter.

  2. Uncovering the Relationship between Sulphation Patterns and Conformation of Iduronic Acid in Heparan Sulphate

    NASA Astrophysics Data System (ADS)

    Hsieh, Po-Hung; Thieker, David F.; Guerrini, Marco; Woods, Robert J.; Liu, Jian

    2016-07-01

    The L-iduronic acid (IdoA) residue is a critically important structural component in heparan sulphate polysaccharide for the biological functions. The pyranose ring of IdoA is present in 1C4-chair, 2SO-skew boat, and less frequently, in 4C1-chair conformations. Here, we analyzed the conformation of IdoA residue in eight hexasaccharides by NMR. The data demonstrate a correlation between the conformation of IdoA and sulphations in the surrounding saccharide residues. For the 2-O-sulpho IdoA residue, a high degree of sulphation on neighboring residues drives ring dynamics towards the 2SO-skew boat conformer. In contrast, the nonsulphated IdoA residue is pushed towards the 1C4-chair conformer when the neighboring residues are highly sulphated. Our data suggest that the conformation of IdoA is regulated by the sulphation pattern of nearby saccharides that is genetically controlled by the heparan sulphate biosynthetic pathway.

  3. Uncovering the Relationship between Sulphation Patterns and Conformation of Iduronic Acid in Heparan Sulphate.

    PubMed

    Hsieh, Po-Hung; Thieker, David F; Guerrini, Marco; Woods, Robert J; Liu, Jian

    2016-07-14

    The L-iduronic acid (IdoA) residue is a critically important structural component in heparan sulphate polysaccharide for the biological functions. The pyranose ring of IdoA is present in (1)C4-chair, (2)SO-skew boat, and less frequently, in (4)C1-chair conformations. Here, we analyzed the conformation of IdoA residue in eight hexasaccharides by NMR. The data demonstrate a correlation between the conformation of IdoA and sulphations in the surrounding saccharide residues. For the 2-O-sulpho IdoA residue, a high degree of sulphation on neighboring residues drives ring dynamics towards the (2)SO-skew boat conformer. In contrast, the nonsulphated IdoA residue is pushed towards the (1)C4-chair conformer when the neighboring residues are highly sulphated. Our data suggest that the conformation of IdoA is regulated by the sulphation pattern of nearby saccharides that is genetically controlled by the heparan sulphate biosynthetic pathway.

  4. Three decades after peak acid deposition: Environmental memories of legacy pollutant sulphate in the northern Czech Republic

    NASA Astrophysics Data System (ADS)

    Marx, Anne; Hintze, Simone; Sanda, Martin; Jankovec, Jakub; Oulehle, Filip; Dusek, Jaromir; Vogel, Tomas; van Geldern, Robert; Barth, Johannes A. C.

    2017-04-01

    A hydrological and physicochemical analysis was conducted in the granitic Uhlirska headwater catchment (1.78 km2) located in the Jizera Mountains in the northern Czech Republic. Due to its location in the Black Triangle (an area with excessive acid rain deposition in the 1980s) it received among the highest inputs of anthropogenic acid depositions in Europe. An analysis of sulphate distribution in deposition, soil water, stream water and groundwater compartments allowed to establish a sulphate mass-balance (deposition input minus surface water export) and helped to evaluate which changes occurred since the last evaluation of the catchment in 1997. The determined sulphate concentrations decreased in the following order: peatland groundwater > groundwater from 20 m below ground level (bgl) > groundwater from 30 m bgl > stream water > groundwater from 10 m bgl > hillslope soil water > peatland soil water > bulk deposition. Our results show that average deposition reductions of 62 % did not result in equal changes of the sulphate mass-balance, which changed by only 47 %. This difference indicates that sulphate must have been stored over decades in the catchment and still originates from internal sources such as the groundwater body and peatland soil. This suggests that the Uhlirska catchment is subject to delayed recovery from anthropogenic acid depositions and remains a net source of stored sulphur even after three decades of declining inputs. Elevated stream water sulphate concentrations after the unusually dry summer 2015 may imply importance of weather patterns for future recovery from acidification.

  5. Folic acid improve developmental toxicity induced by aluminum sulphates.

    PubMed

    Yassa, Heba A; George, Safaa M; Mohamed, Heba K

    2017-03-01

    Aluminum sulphate has a significant toxic effects for humans. Aluminum is one of the most abundant metal on the Earth crust. The purpose of this study is to evaluate the effects of short term exposure to aluminum sulphate on the bone development of the fetuses in rats, and if folic acid has a protective role upon that effects or not. Forty female rats were used, ten per group, GI served as negative control (receive nothing except normal feeding and water), GII served as positive control (receive water by gastric gavage), GIII treated with aluminum sulphate orally by gastric gavage and GIV treated with aluminum sulphate with folic acid. Mating occurred and known by presence of vaginal plug in the female rats. Rats were killed on day 18 of gestation. The female rats weight were significantly reduced in the treated group if compared with the control group (p>0.001), all parameters of the fetuses, fetal weight, malformation and the crown rump length reduced significantly p value were <0.000, <0.001, and <0.000 respectively. In histopathological results the aluminum treated group showed severe limited area of preossfication in fetuses vertebrae. Folic acid gave a protective role for all the hazardous effects of aluminum sulphate and prove the diameters measured and also the histopathological effects. Aluminum sulphate can produce hazardous effects on bone of the fetuses, which may affect the life style of these fetuses later on. Folic acid might give a protective role and so should be given to females who tried to conceive. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Remediation of acidic industrial effluents by sulphate reducing bioreactors.

    PubMed

    Sheoran, V; Chaudhary, R; Tholia, N K

    2012-07-01

    This research work was designed to examine the feasibility of sulphate reducing bioreactors with organic substrates, containing manures, and other cellulosic wastes for remediation of acidic industrial wastewater on bench scale. The pH of the wastewater increased from 5.5. to 7.18, alkalinity from 0 to 2566 mg/L as CaCO3, acidity removal was from 357 to 210 mg/L as CaCO3, sulphate removal was 92.7%, lead removal was 97.3%, zinc- 99.8%, copper-97.5%, cobalt-99.4%, manganese-98.9%, nickel- 98.3% and iron 99.5%, were observed in this study after the maximum retention of 106 days. This paper describes bioremediation as a state-of-art for the treatment of wastewater from the industries.

  7. Diversity and activity of sulphur-oxidizing bacteria and sulphate-reducing bacteria in landfill cover soils.

    PubMed

    Xia, F F; Su, Y; Wei, X M; He, Y H; Wu, Z C; Ghulam, A; He, R

    2014-07-01

    Sulphur bioconversion in landfill cover soils, including the metabolism of sulphur-oxidizing bacteria (SOB) and sulphate-reducing bacteria (SRB), is one of the important processes affecting H2 S emission from landfills. In this study, two landfills with or without landfill gas collection and utilization system were investigated to characterize the role of biotic and abiotic factors affecting diversity and activity of SOB and SRB in the landfill cover soils. The results revealed that the potential sulphur oxidation rates (SORs) and sulphate reduction rates (SRRs) varied with landfill sites and depths. SOR was significantly correlated with pH and SO4 (2-) , while SRR was significantly related with pH. The populations of both SOB and SRB were low in the acidic landfill cover soils (pH = 4.7-5.37). Cloning and terminal restriction fragment length polymorphism profiles of soxB and dsrB showed that SOB including Halothiobacillus, Thiobacillus, Thiovirga and Bradyrhizobium, and SRB including Desulfobacca, Desulforhabdus and Syntrophobacter dominated in the landfill cover soils, and their distributions were affected mainly by pH value and organic matter contents of soils. High diversity of sulphur-oxidizing bacteria (SOB) and sulphate-reducing bacteria (SRB) presented in the landfill cover soils. Among the physicochemical properties of soils (moisture content, pH, organic materials, SO4 (2-) , acid volatile sulphide and total sulphur), pH was the most important factor affecting the diversity and activity of SOB and SRB in the landfill cover soils. Higher pH of landfill cover soils (i.e. neutral or slight alkaline) was favourable for the growth of SOB and SRB, leading to a rapid bioconversion of sulphur. These findings are helpful to optimize sulphur biotransformation in landfill cover soils and to control odour pollution at landfills. © 2014 The Society for Applied Microbiology.

  8. Predicting sulphate adsorption/desorption in forest soils: evaluation of an extended Freundlich equation.

    PubMed

    Gustafsson, Jon Petter; Akram, Muhammad; Tiberg, Charlotta

    2015-01-01

    Sulphate adsorption and desorption can delay the response in soil acidity against changes in acid input. Here we evaluate the use of an extended Freundlich equation for predictions of pH-dependent SO4 adsorption and desorption in low-ionic strength soil systems. Five B horizons from Spodosols were subjected to batch equilibrations at low ionic strength at different pHs and dissolved SO4 concentrations. The proton coadsorption stoichiometry (η), i.e. the number of H(+) ions co-adsorbed for every adsorbed SO4(2)(-) ion, was close to 2 in four of five soils. This enabled the use of a Freundlich equation that involved only two adjustable parameters (the Freundlich coefficient KF and the non-ideality parameter m). With this model a satisfactory fit was obtained when only two data points were used for calibration. The root-mean square errors of log adsorbed SO4 ranged from 0.006 to 0.052. The model improves the possibility to consider SO4 adsorption/desorption processes correctly in dynamic soil chemistry models.

  9. Humic acid adsorption and surface charge effects on schwertmannite and goethite in acid sulphate waters.

    PubMed

    Kumpulainen, Sirpa; von der Kammer, Frank; Hofmann, Thilo

    2008-04-01

    In acid conditions, as in acid mine drainage waters, iron oxide particles are positively charged, attracting negatively charged organic particles present in surrounding natural waters. Schwertmannite (Fe8O8(OH)6SO4) and goethite (alpha-FeOOH) are the most typical iron oxide minerals found in mine effluents. We studied schwertmannite formation in the presence of humic acid. Further, surface charge and adsorption of humic acid on synthetic schwertmannite and goethite surfaces in pH 2-9 and in humic acid concentrations of 0.1-100 mg/L C were examined. Schwertmannite did precipitate despite the presence of humic acid, although it contained more sulphate and had higher specific surface area than ordinary schwertmannite. Specific surface area weighted results showed that schwertmannite and goethite had similar humic acid adsorption capacities. Sulphate was released from schwertmannite surfaces with increasing pH, resulting in an increase in specific surface area. Presence of sulphate in solution decreased the surface charge of schwertmannite and goethite similarly, causing coagulation. In acid conditions (pH 2-3.5), according to the zeta potential, schwertmannite is expected to coagulate even in the presence of high concentrations of humic acid (< or = 100 mg/L C). However, at high humic acid concentrations (10-100 mg/L C) with moderate acid conditions (pH>3.5), both schwertmannite and goethite surfaces are strongly negatively charged (zeta potential < -30 mV) thus posing a risk for colloid stabilization and colloidal transport.

  10. Isotope composition of sulphate in acid mine drainage as measure of bacterial oxidation

    USGS Publications Warehouse

    Taylor, B.E.; Wheeler, M.C.; Nordstrom, D.K.

    1984-01-01

    The formation of acid waters by oxidation of pyrite-bearing ore deposits, mine tailing piles, and coal measures is a complex biogeochemical process and is a serious environmental problem. We have studied the oxygen and sulphur isotope geochemistry of sulphides, sulphur, sulphate and water in the field and in experiments to identify sources of oxygen and reaction mechanisms of sulphate formation. Here we report that the oxygen isotope composition of sulphate in acid mine drainage shows a large variation due to differing proportions of atmospheric- and water-derived oxygen from both chemical and bacterially-mediated oxidation. 18O-enrichment of sulphate results from pyrite oxidation facilitated by Thiobacillus ferrooxidans in aerated environments. Oxygen isotope analysis may therefore be useful in monitoring the effectiveness of abatement programmes designed to inhibit bacterial oxidation. Sulphur isotopes show no significant fractionation between pyrite and sulphate, indicating the quantitative insignificance of intermediate oxidation states of sulphur under acid conditions. ?? 1984 Nature Publishing Group.

  11. Biogenic Sulphate, Sulphur Dioxide and Methanesulphonic Acid Ratios over the North Atlantic

    NASA Astrophysics Data System (ADS)

    Seguin, A.; Norman, A.; Wadleigh, M.; Siauw, A.; Eaton, S.

    2006-12-01

    Methanesulphonic acid (MSA) and sulphate are the end products of two different oxidation pathways of atmospheric dimethylsulphide (DMS). Sulphate aerosols can act as cloud condensation nuclei that affect incoming solar radiation and thus climate. The branching ratio cannot be measured using sulphate concentrations alone due to anthropogenic sulphate contributions. Stable isotope techniques, however, can be used to define continental and biogenic emissions, determine the origin of sulphate in aerosol samples and provide insight into DMS oxidation. Size segregated aerosol filters, sulphur dioxide and atmospheric DMS were collected during the summer 2003 Canadian Surface Ocean Lower Atmospheric Study (C-SOLAS) over the North Atlantic. Isotope values along with sulphate, MSA and cation concentrations were analysed. Non-sea salt (NSS) sulphate concentrations where as high as 11000 ng/m3. Biogenic sulphate concentrations ranged between 100 and 800 ng/m3 while biogenic sulphur dioxide concentrations ranged between 20 and 4000 ng/m3. Polluted air masses see an increase in biogenic sulphur dioxide indicating an influence of human activity on the oxidation pathways of DMS. MSA and biogenic sulphur dioxide concentrations are compared to the biogenic sulphate to explore the branching ratio.

  12. Nanocrosses of lead sulphate as the negative active material of lead acid batteries

    NASA Astrophysics Data System (ADS)

    Liu, Yi; Gao, Pengran; Bu, Xianfu; Kuang, Guizhi; Liu, Wei; Lei, Lixu

    2014-10-01

    Lead sulphate transforms into PbO2 and Pb in the positive and negative electrodes, respectively, when a lead acid battery is charged, thus, it is an active material. It is also generally acknowledged that sulphation results in the failure of lead acid batteries; therefore, it is very interesting to find out how to make lead sulphate more electrochemically active. Here, we demonstrate that nanocrystalline lead sulphate can be used as excellent negative active material in lead acid batteries. The lead sulphate nanocrystals, which are prepared by a facile chemical precipitation of aqueous lead acetate and sodium sulphate in a few minutes, look like crosses with diameter of each arm being 100 nm to 3 μm. The electrode is effectively formed in much shorter time than traditional technique, yet it discharges a capacity of 103 mA h g-1 at the current density of 120 mA g-1, which is 24% higher than that discharged by the electrode made from leady oxide under the same condition. During 100% DOD cycles, more than 80% of that capacity remains in 550 cycles. These results show that lead sulphate can be a nice negative active material in lead acid batteries.

  13. Elecrokinetic separation of sulphate and lead from sludge of spent lead acid battery.

    PubMed

    Maruthamuthu, S; Dhanibabu, T; Veluchamy, A; Palanichamy, S; Subramanian, P; Palaniswamy, N

    2011-10-15

    A novel electrokinetic (EK) technique is applied to separate lead and sulphate from the sludge of used/spent lead acid battery. XRD reveals that the sludge is a mixture of (PbO)(4) [Pb(SO(4))], Pb(2)O(3), PbSO(4), Pb(S(2)O(3)) and Pb(2)(SO(4)) which upon DC voltage application in a EK cell employing either titanium electrodes or titanium substrate insoluble anode as electrodes caused migration of sulphates and lead ions respectively into anode and cathode compartments, and accumulation of insoluble lead oxides at the central compartment. The insoluble lead oxides accumulated at the central compartment in the ratio 1:3, respectively for the high oxygen over-voltage Ti-anode (Ti-EK cell) and low oxygen over-voltage TSIA-anode (TSIA-EK cell) shows the superiority of Ti anode over TSIA anode. Also thermal investigation reveals Pb deposited at Ti-cathode is superior to that from TSIA cathode. This process does not release air/soil pollutants which are usually associated with high temperature pyrotechnic process.

  14. Acidic conjugate of phenols in insects; glucoside phosphate and glucoside sulphate derivatives.

    PubMed

    Ngah, W Z; Smith, J N

    1983-06-01

    Conjugates of p-nitrophenol in nine species of insects were identified by paper chromatography and ionophoresis as the glucoside, the sulphate, the phosphate and the glucoside phosphate. Metabolites with similar properties to the glucoside phosphates were also formed from 8-hydroxyquinoline, 1-naphthol and 4-methylumbelliferone in Tenebrio larvae. Tenebrio larvae also metabolized p-nitrophenol to a compound believed to be p-nitrophenyl glucoside-6-sulphate. None of the nine species of insect used was able to metabolize [14C]benzoic acid to a glucoside-phosphate or glucoside-sulphate conjugate.

  15. Effect of folic acid and zinc sulphate on endocrine parameters and seminal antioxidant level after varicocelectomy.

    PubMed

    Nematollahi-Mahani, S N; Azizollahi, G H; Baneshi, M R; Safari, Z; Azizollahi, S

    2014-04-01

    Varicocele is among the most common problems which may lead to male infertility. Spermatogenesis is impaired as a consequence of this vascular defect, through mechanisms that are not well described. This study aimed to evaluate serum hormonal level (inhibin B, FSH and testosterone) and seminal plasma antioxidant defence levels after folic acid and zinc sulphate administration in varicocelectomised patients. Participants were randomly allocated to four experimental groups. Our randomisation schedule was as follows: zinc sulphate/folic acid, folic acid, zinc sulphate and placebo. The patients underwent varicocelectomy, before which a blood and semen sample were obtained and also three and six months after varicocelectomy for evaluation of blood hormonal level (FSH, testosterone, inhibin B) and seminal oxidative stress status (nitric oxide, superoxide dismutase, total antioxidant capacity). Patients in different groups took orally one capsule per day after dinner following varicocelectomy for 6 months. A significant rise in peripheral blood inhibin B and seminal plasma activity was detected in the zinc sulphate/folic acid group after 6 months. The present clinical trial indicates a change in the hormonal status of varicocelectomised patients following long-term administration of zinc sulphate and folic acid. © 2013 Blackwell Verlag GmbH.

  16. Partial characterization of biosurfactant from Lactobacillus pentosus and comparison with sodium dodecyl sulphate for the bioremediation of hydrocarbon contaminated soil.

    PubMed

    Moldes, A B; Paradelo, R; Vecino, X; Cruz, J M; Gudiña, E; Rodrigues, L; Teixeira, J A; Domínguez, J M; Barral, M T

    2013-01-01

    The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-). The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR) that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage), as well as CH2-CH3 and C-O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg(-1) of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment.

  17. Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

    PubMed Central

    Moldes, A. B.; Paradelo, R.; Vecino, X.; Cruz, J. M.; Gudiña, E.; Rodrigues, L.; Teixeira, J. A.; Domínguez, J. M.; Barral, M. T.

    2013-01-01

    The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-). The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR) that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage), as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment. PMID:23691515

  18. Arylsulphatase activity and sulphate content in relation to crop rotation and fertilization of soil

    NASA Astrophysics Data System (ADS)

    Siwik-Ziomek, Anetta; Lemanowicz, Joanna; Koper, Jan

    2016-07-01

    The aim of the study was to investigate the effect of varying rates of FYM (0, 20, 40, 60 Mg ha-1) and nitrogen N0, N1, N2, and N3 on the content of sulphate sulphur (VI) and the activity of arylsulphatase, which participates in the transformations of this element in Haplic Luvisol. The study report is based on a long-term field experiment with two different crop rotations: A - recognized as exhausting the humus from soil and B - recognized as enriching the soil with humus. During the cultivation of the plants, the soil was sampled four times from corn and a red clover cultivar and grass. The FYM fertilization rate for which the highest arylsulphatase activity and the content of sulphates were identified was 60 Mg ha-1. An inhibitory effect of high rates (90 and 135 kg N ha-1) of ammonium nitrate on the arylsulphatase activity was also observed. A significant correlation between the content of carbon, nitrogen, and sulphates and the arylsulphatase activity was recorded. The investigation on the effect of combined application of farmyard manure and mineral nitrogen fertilization on the activity of arylsulphatase participating in the sulphur cycling was launched to examine the problem in detail.

  19. Profile distribution and temporal changes of sulphate and nitrate contents and related soil properties under beech and spruce forests.

    PubMed

    Tejnecký, Václav; Bradová, Monika; Borůvka, Luboš; Němeček, Karel; Sebek, Ondřej; Nikodem, Antonín; Zenáhlíková, Jitka; Rejzek, Jan; Drábek, Ondřej

    2013-01-01

    The behaviour of principal inorganic anions in forest soils, originating mainly from acid deposition, strongly influences the forest ecosystem response on acidification. The aim of this study was to describe seasonal and temporal changes of sulphate and nitrate contents and related soil properties under beech and spruce forests in a region heavily impacted by acidification. The Jizera Mountains area (Czech Republic) was chosen as such a representative mountainous soil ecosystem. Soil samples were collected at monthly intervals from April to October during the years 2008-2010 under both beech and spruce stands. Soil samples were collected from surface fermentation (F) and humified (H) organic horizons, humic (A) organo-mineral horizons and subsurface mineral (B) horizons (cambic or spodic). A deionised water extract was applied to unsieved fresh samples and the content of anions in these extracts was determined by ion chromatography (IC). In the studied soil profiles, the lowest amount of SO(4)(2-) was found in the organo-mineral A horizons under both types of vegetation. Under spruce the highest amount of SO(4)(2-) was determined in mineral spodic (B) horizons, where a strong sorption influence of Fe and Al oxy-hydroxides is expected. Under beech the highest amount was observed in the surface organic F horizons (forest floor). The amount of NO(3)(-) is highest in the F horizons and decreases with increasing soil profile depth under both types of vegetation. A significantly higher amount of NO(3)(-) was determined in soils under the beech stand compared to spruce. For both soil environments - under beech and also spruce stands - we have determined a general increase of water-extractable SO(4)(2-) and NO(3)(-) during the whole monitoring period. The behaviour of SO(4)(2-) and NO(3)(-) in the soils is strongly related to the dynamics of soil organic matter and particularly to the DOC.

  20. Hexavalent chromium reduction in contaminated soil: A comparison between ferrous sulphate and nanoscale zero-valent iron.

    PubMed

    Di Palma, L; Gueye, M T; Petrucci, E

    2015-01-08

    Iron sulphate (FeSO4) and colloidal nano zero-valent iron (nZVI) as reducing agents were compared, with the aim of assessing their effectiveness in hexavalent chromium [Cr(VI)] removal from a contaminated industrial soil. Experiments were performed on soil samples collected from an industrial site where a nickel contamination, caused by a long-term productive activity, was also verified. The influence of reducing agents amount with respect to chromium content and the effectiveness of deoxygenation of the slurry were discussed. The soil was fully characterized before and after each test, and sequential extractions were performed to assess chemico-physical modifications and evaluate metals mobility induced by washing. Results show that both the reducing agents successfully lowered the amount of Cr(VI) in the soil below the threshold allowed by Italian Environmental Regulation for industrial reuse. Cr(VI) reduction by colloidal nZVI proved to be faster and more effective: the civil reuse of soil [Cr(VI)<2mg/kg] was only achieved using colloidal nZVI within 60min adopting a nZVI/Cr(VI) molar ratio of 30. The reducing treatment resulted in an increase in the amount of chromium in the oxide-hydroxide fraction, thus confirming a mechanism of chromium-iron hydroxides precipitation. In addition, a decrease of nickel (Ni) and lead (Pb) content in soil was also observed when acidic conditions were established.

  1. Acid rain footprint three decades after peak deposition: Long-term recovery from pollutant sulphate in the Uhlirska catchment (Czech Republic).

    PubMed

    Marx, A; Hintze, S; Sanda, M; Jankovec, J; Oulehle, F; Dusek, J; Vitvar, T; Vogel, T; van Geldern, R; Barth, J A C

    2017-11-15

    The granitic Uhlirska headwater catchment with a size of 1.78km(2) is located in the Jizera Mountains in the northern Czech Republic and received among the highest inputs of anthropogenic acid depositions in Europe. An analysis of sulphate (SO4(2-)) distribution in deposition, soil water, stream water and groundwater compartments allowed to establish a SO4(2-) mass-balance (deposition input minus surface water export) and helped to evaluate which changes occurred since the last evaluation of the catchment in 1997. The determined SO4(2-) concentrations decreased in the following order: wetland groundwater>groundwater from 20m below ground level (bgl)>groundwater from 30m bgl>stream water>groundwater from10m bgl>hillslope soil water>wetland soil water>bulk deposition with median values of 0.24, 0.21, 0.17, 0.15, 0.11, 0.07, 0.03 and 0.01mmolL(-1), respectively. Our results show that average deposition reductions of 62% did not result in equal changes of the sulphate mass-balance, which changed by only 47%. This difference occurs because sulphate originates from internal sources such as the groundwater and soil water. The Uhlirska catchment is subject to delayed recovery from anthropogenic acid depositions and remains a net source of stored sulphur even after three decades of declining inputs. The wetland groundwater and soil water provide environmental memories of legacy pollutant sulphate. Elevated stream water sulphate concentrations after the unusually dry summer 2015 imply importance of weather and climate patterns for future recovery from acidification. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Conversion of pollutants to fertilisers: ion exchange synthesis of potassium sulphate from acidic mine waters.

    PubMed

    Muraviev, D

    2003-01-01

    The paper reports the results obtained by the development of ion exchange synthesis of K2SO4 from the natural acidic mine waters (AMW) of Rio Tinto area (Huelva, Spain). The process flowsheet includes several sequential stages permitting production of potassium sulphate and desalinated water along with the recovery of four metals.

  3. Bacteria and acid drainage from coal refuse: inhibition by sodium lauryl sulphate and sodium benzoate

    SciTech Connect

    Dugan, P.R.; Apel, W.A.

    1983-01-01

    Studies have shown that the application of an aqueous solution of sodium lauryl sulphate and sodium benzoate to the surface of high-sulphur coal refuse inhibits the activity of iron- and sulphur-oxidising chemo-autotrophic bacteria and reduces the amount of acid drainage from the refuse. Further studies are recommended to assess the usefulness of this method for controlling formation of acid mine drainage in the field.

  4. Partial purification of fatty-acid binding protein by ammonium sulphate fractionation.

    PubMed

    Avanzati, B; Catalá, A

    1983-07-01

    By fractionation of rat liver cytosol with 70% saturation ammonium sulphate, a soluble fraction showing high affinity for oleic acid was obtained. The binding of oleic acid to this fraction was inhibited by flavaspidic acid. The molecular weight of the main protein present in this fraction was 12 000 as determined by SDS-poly-acrylamide-gel electrophoresis. This soluble fraction stimulated the transfer of oleic acid from microsomes to phosphatidylcholine liposomes as demonstrated by a transfer assay in vitro. The behaviour of this fraction is similar to that described for fatty-acid binding protein.

  5. Rare earth element geochemistry of acid-sulphate and acid-sulphate-chloride geothermal systems from Yellowstone National Park, Wyoming, USA

    SciTech Connect

    Lewis, A.J.; Palmer, M.R.; Kemp, A.J.; Sturchio, N.C.

    1997-02-01

    Rare earth element (REE) concentrations have been determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) in acid-sulphate and acid-sulphate-chloride waters and the associated sinters and volcanic rocks from the Yellowstone National Park (YNP), Wyoming, USA, geothermal system. REE concentrations in the volcanic rocks range from 222 to 347 ppm: their chondrite-normalised REE patterns are typical of upper continental crust, with LREE > HREE and negative Eu anomalies. Total REE concentrations in the fluids range from 3 to 1133 nmol kg{sup -1} ({ge}162 ppm), and {Sigma}REE concentrations in sinter are {ge}181 ppm. REE abundances and patterns in drill core material from YNP indicate some REE mobility. Relative to the host rocks the REE patterns of the fluids are variably depleted in HREEs and LREEs, and usually have a pronounced positive Eu anomaly. This decoupling of Eu from the REE suite suggests that (1) Eu has been preferentially removed either from the host rock glass or from the host rock minerals, or (2) the waters are from a high temperature or reducing environment where Eu{sup 2+} is more soluble than the trivalent REEs. Since the latter is inconsistent with production of acid-sulphate springs in a low temperature, oxidising near-surface environment, we suggest that the positive Eu anomalies in the fluids result from preferential dissolution of a Eu-rich phase in the host rock. Spatial and temporal variations in major element chemistry and pH of the springs sampled from Norris Geyser Basin and Crater Hills accompany variations in REE concentrations and patterns of individual geothermal springs. These are possibly related to changes in subsurface plumbing, which results in variations in mixing and dilution of the geothermal fluids and may have lead to changes in the extent and nature of REE complexing. 37 refs., 7 figs., 4 tabs.

  6. Purification of IgG from serum with caprylic acid and ammonium sulphate precipitation is not superior to ammonium sulphate precipitation alone.

    PubMed

    Mohanty, J G; Elazhary, Y

    1989-01-01

    Immunoglobulin G (IgG) from bovine serum raised against Aeromonas Salmonicida was purified by ammonium sulphate precipitation (ASP) or caprylic acid treatment followed by ammonium sulphate precipitation (CAAS). Purity of IgG samples prepared by both methods were examined by High Performance Gel Permeation Chromatography, electrophoresis and antibody activity assay. Results suggest that IgG prepared by ASP is better than that obtained by CAAS method in terms of the yield of the IgG monomers and the recovery of the antibody activity.

  7. Does folic acid and zinc sulphate intervention affect endocrine parameters and sperm characteristics in men?

    PubMed

    Ebisch, I M W; Pierik, F H; DE Jong, F H; Thomas, C M G; Steegers-Theunissen, R P M

    2006-04-01

    We evaluated pre- and post-intervention endocrine and semen parameters in a double-blind, placebo-controlled intervention study to investigate the underlying mechanism of increased sperm concentration after folic acid and zinc sulphate intervention. A total of 47 fertile and 40 subfertile males participated in a 26-week intervention study consisting of a daily treatment with folic acid (5 mg/day) and zinc sulphate (66 mg/day), or placebo. Pre- and post-intervention semen parameters, serum folate, zinc, follicle-stimulating hormone (FSH), testosterone and inhibin B concentrations were measured. The results indicated that intervention treatment significantly increased sperm concentration in subfertile males. Other semen and endocrine parameters were not affected by intervention treatment. At baseline, positive correlations were found between serum zinc and sperm concentration, motility and inhibin B. Serum zinc and FSH were inversely correlated. As (already) well known from previous research, inhibin B positively correlated with sperm concentration, motility and morphology, and was inversely correlated with FSH. The latter was positively correlated with testosterone. In addition, testosterone and inhibin B were inversely correlated. After intervention, the correlations with zinc disappeared. We conclude that the increase in sperm concentration after folic acid and zinc sulphate intervention is not the result of alterations in FSH, testosterone or inhibin B concentrations. Although zinc and folate have several effects on spermatogenesis, the underlying mechanisms involved are not clear.

  8. Characterization of a sodium dodecyl sulphate-degrading Pseudomonas sp. strain DRY15 from Antarctic soil.

    PubMed

    Halmi, M I E; Hussin, W S W; Aqlima, A; Syed, M A; Ruberto, L; MacCormack, W P; Shukor, M Y

    2013-11-01

    A bacterium capable of biodegrading surfactant sodium dodecyl sulphate (SDS) was isolated from Antarctic soil. The isolate was tentatively identified as Pseudomonas sp. strain DRY15 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. Growth characteristic studies showed that the bacterium grew optimally at 10 degrees C, 7.25 pH, 1 g l(-1) SDS as a sole carbon source and 2 g l(-1) ammonium sulphate as nitrogen source. Growth was completely inhibited at 5 g l(-1) SDS. At a tolerable initial concentration of 2 g l(-1), approximately 90% of SDS was degraded after an incubation period of eight days. The best growth kinetic model to fit experimental data was the Haldane model of substrate inhibition with a correlation coefficient value of 0.97. The maximum growth rate was 0.372 hr(-1) while the saturation constant or half velocity constant (Ks) and inhibition constant (Ki), were 0.094% and 11.212 % SDS, respectively. Other detergent tested as carbon sources at 1 g l(-1) was Tergitol NP9, Tergitol 15S9, Witconol 2301 (methyl oleate), sodium dodecylbenzene sulfonate (SDBS), benzethonium chloride, and benzalkonium chloride showed Tergitol NP9, Tergitol 15S9, Witconol 2301 and the anionic SDBS supported growth with the highest growth exhibited by SDBS.

  9. Speleothem records of acid sulphate deposition and organic carbon mobilisation

    NASA Astrophysics Data System (ADS)

    Wynn, Peter; Fairchild, Ian; Bourdin, Clement; Baldini, James; Muller, Wolfgang; Hartland, Adam; Bartlett, Rebecca

    2017-04-01

    Dramatic increases in measured surface water DOC in recent decades have been variously attributed to either temperature rise, or destabilisation of long-term soil carbon pools following sulphur peak emissions status. However, whilst both drivers of DOC dynamics are plausible, they remain difficult to test due to the restricted nature of the available records of riverine DOC flux (1978 to present), and the limited availability of SO2 emissions inventory data at the regional scale. Speleothems offer long term records of both sulphur and carbon. New techniques to extract sulphur concentrations and isotopes from speleothem calcite have enabled archives of pollution history and environmental acidification to be reconstructed. Due to the large dynamic range in sulphur isotopic values from end member sources (marine aerosol +21 ‰ to continental biogenic emissions -30 ‰) and limited environmental fractionation under oxidising conditions, sulphur isotopes form an ideal tracer of industrial pollution and environmental acidification in the palaeo-record. We couple this acidification history to the carbon record, using organic matter fluorescence and trace metals. Trace metal ratios and abundance can be used to infer the type and size of organic ligand and are therefore sensitive to changes in temperature as a driver of organic carbon processing and biodegradation. This allows fluorescent properties and ratios of trace metals in speleothem carbonate to be used to represent both the flux of organic carbon into the cave as well as the degradation pathway. Here we present some of the first results of this work, exploring sulphur acidification as a mechanistic control on carbon solubility and export throughout the twentieth century.

  10. The rare earth element geochemistry of acid-sulphate and acid-sulphate-chloride geothermal systems from Yellowstone National Park, Wyoming, USA

    NASA Astrophysics Data System (ADS)

    Lewis, Anita J.; Palmer, Martin R.; Sturchio, Neil C.; Kemp, Anthony J.

    1997-02-01

    Rare earth element (REE) concentrations have been determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) in acid-sulphate and acid-sulphate-chloride waters and the associated sinters and volcanic rocks from the Yellowstone National Park (YNP), Wyoming, USA, geothermal system. REE concentrations in the volcanic rocks range from 222 to 347 ppm; their chondite-normalised REE patterns are typical of upper continental crust, with LREE > HREE and negative Eu anomalies. Total REE concentrations in the fluids range from 3 to 1133 nmol kg -1 (≥ 162 ppm), and ΣREE concentrations in sinter are ≥ 181 ppm. REE abundances and patterns in drill core material from YNP indicate some REE mobility. Normalisation of REE concentrations in altered Lava Creek Tuff (LCT) from Y-12 drill core to REE concentrations in fresh LCT indicate that the REE overall have been depleted with the exception of Eu, which has been decoupled from the REE series and concentrated in the altered rocks. Relative to the host rocks the REE patterns of the fluids are variably depleted in HREEs and LREEs, and usually have a pronounced positive Eu anomaly. This decoupling of Eu from the REE suite suggests that (1) Eu has been preferentially removed either from the host rock glass or from the host rock minerals, or (2) the waters are from a high temperature or reducing environment where Eu 2+ is more soluble than the trivalent REEs. Since the latter is inconsistent with production of acid-sulphate springs in a low temperature, oxidising near-surface environment, we suggest that the positive Eu anomalies in the fluids result from preferential dissolution of a Eu-rich phase in the host rock. Spatial and temporal variations in major element chemistry and pH of the springs sampled from Norris Geyser Basin and Crater Hills accompany variations in REE concentrations and patterns of individual geothermal springs. These are possibly related to changes in subsurface plumbing, which results in variations in

  11. Improved lead recovery and sulphate removal from used lead acid battery through electrokinetic technique.

    PubMed

    Soundarrajan, C; Sivasankar, A; Maruthamuthu, S; Veluchamy, A

    2012-05-30

    This paper presents improvement in lead (Pb) recovery and sulphate removal from used Pb acid battery (ULAB) through Electrokinetic technique, a process aimed to eliminate environmental pollution that arises due to emission of gases and metal particles from the existing high temperature pyrometallurgical process. Two different cell configurations, (1) one with Nafion membrane placed between anode and middle compartments and Agar membrane between cathode and middle compartments and (2) another with only Agar membrane placed between both sides of the middle compartments were designed for the Pb and sulphate separation from ULAB. This paper concludes that the cell with only Agar membranes performed better than the cell with Nafion and Agar membranes in combinations and also explains the mechanism underlying the chemical and electrochemical processes in the cell.

  12. Pressure-oxidation autoclave as an analogue for acid-sulphate alteration in epithermal systems

    NASA Astrophysics Data System (ADS)

    Craw, D.

    2006-07-01

    Gold extraction at the Macraes gold mine in New Zealand involves concentration of pyrite and arsenopyrite, oxidation of those sulphides, then cyanidation. The ore concentrate is predominantly Otago Schist host rock (andesitic composition) with up to 15% sulphides. The oxidation step is conducted on ore concentrate slurry in an autoclave at 225°C and 3,800 kPa oxygen gas pressure with continuous feed. The slurry takes ca. 1 h to pass through the autoclave, during which time the sulphides are almost completely oxidised. Sulphide oxidation causes strong acidification of the slurry, which is maintained at pH of 1-2 by addition of CaCO3. Scales form on walls in the autoclave, with minerals reflecting progressive oxidation and alteration of the ore through the system. The schist in the ore feed has mineralogy similar to propylitically altered andesite: quartz, albite, muscovite, chlorite, and pyrite. Muscovite undergoes almost complete dissolution, with associated precipitation of quartz and alunite (KAl3(SO4)2(OH)6). Other principal minerals deposited and discharged include anhydrite (and/or gypsum), jarosite (KFe3(SO4)2(OH)6), hematite (and/or amorphous iron oxyhydroxide), and amorphous arsenates. Dissolved ferrous iron passes right through the autoclave, and variably hydrated Fe2+and Fe3+sulphate minerals, including rozenite and szomolnokite (both FeSO4.hydrate) and ferricopiapite (Fe5(SO4)6O(OH).hydrate), are formed along the way. The autoclave chemical system resembles acid-sulphate hydrothermal activity in geothermal systems and high-sulphidation epithermal mineral deposits formed in arc environments. These natural acid-sulphate systems are pervaded by volcanic vapours in the near-surface environment, where widespread dissolution of host rocks occurs and deposition of quartz, alunite, and anhydrite is common. Some of the volume loss associated with these natural systems may be due to dissolution of soluble sulphate minerals by later-stage groundwater incursion.

  13. Development of poly(aspartic acid-co-malic acid) composites for calcium carbonate and sulphate scale inhibition.

    PubMed

    Mithil Kumar, N; Gupta, Sanjay Kumar; Jagadeesh, Dani; Kanny, K; Bux, F

    2015-01-01

    Polyaspartic acid (PSI) is suitable for the inhibition of inorganic scale deposition. To enhance its scale inhibition efficiency, PSI was modified by reacting aspartic acid with malic acid (MA) using thermal polycondensation polymerization. This reaction resulted in poly(aspartic acid-co-malic acid) (PSI-co-MA) dual polymer. The structural, chemical and thermal properties of the dual polymers were analysed by using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and gel permeation chromatography. The effectiveness of six different molar ratios of PSI-co-MA dual polymer for calcium carbonate and calcium sulphate scale inhibition at laboratory scale batch experiments was evaluated with synthetic brine solution at selected doses of polymer at 65-70°C by the static scale test method. The performance of PSI-co-MA dual polymer for the inhibition of calcium carbonate and calcium sulphate precipitation was compared with that of a PSI single polymer. The PSI-co-MA exhibited excellent ability to control inorganic minerals, with approximately 85.36% calcium carbonate inhibition and 100% calcium sulphate inhibition at a level of 10 mg/L PSI-co-MA, respectively. Therefore, it may be reasonably concluded that PSI-co-MA is a highly effective scale inhibitor for cooling water treatment applications.

  14. Fruit acids do not enhance sodium lauryl sulphate-induced cumulative irritant contact dermatitis in vivo.

    PubMed

    Schliemann-Willers, Sibylle; Fuchs, Silke; Kleesz, Peter; Grieshaber, Romano; Elsner, Peter

    2005-01-01

    Combined exposure to different irritants in the workplace may lead to irritant contact dermatitis, which is the main type of occupational dermatitis among bakers and confectioners. Following previous work on "tandem irritation", a panel of healthy volunteers was exposed twice daily for 4 days to the organic fruit acids: citric, malic, and lactic acid, either alone or in tandem application with 0.5% sodium lauryl sulphate (SLS) in a repetitive irritation test. Irritant cutaneous reactions were quantified by visual scoring and non-invasive measurement of transepidermal water loss and skin colour reflectance. Twice daily application of either citric or malic acid alone did not induce a significant irritant reaction. Combined exposure to one of the fruit acids and SLS caused marked barrier disturbance, but the latter irritant effect was smaller than that obtained by combined exposure to SLS and water. Thus, combined exposure to the above-mentioned fruit acids and SLS did not enhance cumulative skin irritation.

  15. Processes and fluxes during the initial stage of acid sulfate soil formation

    NASA Astrophysics Data System (ADS)

    Gröger, J.; Hamer, K.; Schulz, H. D.

    2009-04-01

    acid sulfate soils. Furthermore, these experiments can serve as a model for the initial stage of naturally occurring acid sulfate soil formation. Thus, the results will provide a base for the interpretation of element distribution in the solid phase of natural acid sulfate soil profiles. References DENT, D. L. and PONS, L. J. (1995) A world perspective on acid sulphate soils. Geoderma 67, 263-276. PONS, L. J. (1973) Outline of genesis, characteristics, classification and improvement of acid sulphate soils. In Acid Sulphate Soils - Proceedings of the International Symposium on Acid Sulphate Soils - I Introductory Papers and Bibliography (ed. H. Dost). pp. 3-27

  16. Study on the effect of sulphur, glucose, nitrogen and plant residues on the immobilization of sulphate-S in soil.

    PubMed

    Shahsavani, S

    2009-02-15

    In order to evaluate the relationship between sulphur (S), glucose (G), nitrogen (N) and plant residues (st), on sulphur immobilization and microbial transformation. Five soil samples from 0-30 cm of Bastam farmer's fields of Shahrood area were collected. Eleven treatments with different levels of S, G, N and plant residues (wheat straw) were applied in a randomized block design with three replications and incubated over 20, 45 and 60 days. The immobilization of SO4(-2)-S presented as a percentage of that added, was inversely related to its addition rate. Additions of glucose and plant residues increased with the C-to-S ratio of the added amendments, irrespective of their origins (glucose and plant residues). In the presence of C sources (glucose or plant residues). N significantly increased the immobilization of SO4(-2)-S, whilst the effect of N was insignificant in the absence of a C amendment. In first few days the amounts of added SO4(-2)-S immobilized were linearly correlated with the amounts of added S recovered in the soil microbial biomass. With further incubation the proportions of immobilized SO4(-2)-S remaining as biomass-S decreased. Decrease in biomass-S was thought to be due to the conversion ofbiomass-S into soil organic-S. Glucose addition increased the immobilization (microbial utilization and incorporation into the soil organic matter) of native soil SO4(-2)-S. However, N addition enhance the mineralization of soil organic-S, increasing the concentration of SO4(-2)-S in soil and the extent to which available-S can be immobilized is determined by both the amount of available-S and the availability of an utilizable C source.

  17. Effect of growth temperature on cellular fatty acids in sulphate-reducing bacteria.

    PubMed

    Könneke, Martin; Widdel, Friedrich

    2003-11-01

    The effect of growth temperature on the cellular fatty acid composition of sulphate-reducing bacteria (SRB) was studied in 12 species belonging to eight genera including psychrophiles and mesophiles. Most of these species were of marine origin. The investigated SRB with the exception of four Desulfobacter species exhibited only a minor increase in the proportion of cis-unsaturated fatty acids (by < or = 5% per 10 degrees C) when the growth temperature was decreased; psychrophiles maintained their typically high content of cis-unsaturated fatty acids (around 75% of total fatty acids) nearly constant. The four Desulfobacter species, however, increased the proportion of cis-unsaturated among total fatty acids significantly (by > or =14% per 10 degrees C; measured in late growth phase) with decreasing growth temperature. The ratio between unsaturated and saturated fatty acids in Desulfobacter species changed not only with the growth temperature, but also with the growth state in batch cultures at constant temperature. Changes of cellular fatty acids were studied in detail with D. hydrogenophilus, the most psychrotolerant (growth range 0-35 degrees C) among the mesophilic SRB examined. Desulfobacter hydrogenophilus also formed cis-9,10-methylenehexadecanoic acid (a cyclopropane fatty acid) and 10-methylhexadecanoic acid. At low growth temperature (12 degrees C), the relative amount of these fatty acids was at least threefold lower; this questions the usefulness of 10-methylhexadecanoic acid as a reliable biomarker of Desulfobacter in cold sediments.

  18. 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...

  19. Evaluation and biological characterization of bilayer gelatin/chondroitin-6-sulphate/hyaluronic acid membrane.

    PubMed

    Wang, Tzu-Wei; Sun, Jui-Sheng; Wu, Hsi-Chin; Huang, Yi-Chau; Lin, Feng-Huei

    2007-08-01

    A biodegradable polymer scaffold was developed using gelatin, chondroitin-6-sulphate, and hyaluronic acid in the form of bilayer network. The bilayer porous structure of gelatin-chondroitin-6-sulphate-hyaluronic acid (G-C6S-HA) membrane was fabricated using different freezing temperatures followed by lyophilization. 1-Ethyl-3(3-dimethylaminopropyl) carbodiimide was used as crosslinking agent to improve the biological stability of the scaffold. The morphology, physical-chemical properties, and biocompatibility of bilayer G-C6S-HA membrane were evaluated in this study. The functional groups change in crosslinked G-C6S-HA scaffold was characterized by fourier transform infrared spectroscopy. The retention of glycosaminoglycan contents and matrix degradation rate were also examined by p-dimethylamino benzaldehyde and 2,4,6-trinitrobenzene sulphonic acid, respectively. Water absorption capacity was carried out to study G-C6S-HA membrane water containing characteristics. The morphology of the bilayer G-C6S-HA membrane was investigated under scanning electron microscope and light microscopy. In vitro biocompatibility was conducted with MTT test, LDH assay, as well as histological analysis. The results showed that the morphology of bilayer G-C6S-HA membrane was well reserved. The physical-chemical properties were also adequate. With good biocompatibility, this bilayer G-C6S-HA membrane would be suitable as a matrix in the application of tissue engineering.

  20. Biological treatment of acidic coal refuse using sulphate-reducing bacteria with chicken manure as carbon source.

    PubMed

    Zhang, Mingliang; Wang, Haixia

    2014-01-01

    The performance of using chicken manure as carbon source to promote sulphate-reducing bacteria (SRB) activity within acidic coal refuse to prevent the generation of acidic leachate was investigated in batch and column bioreactors. The bioreactors showed satisfactory performance in biological sulphate reduction, evidenced by the increase in effluent pH, high removal efficiencies of sulphate and metals, and the presence of large numbers of SRB. Scanning electron microscope-energy dispersive spectrometry (EDS) analysis of the formed precipitate indicated the formation of metal sulphides. Chicken manure was observed to play an important role in this treatment, which could not only provide carbon source but also reduce the adverse effect of strong acidity and metal toxicity on SRB activity. Metal removal could be mainly attributed to sulphides precipitation and sorption to chicken manure. This study indicated that SRB with chicken manure could be a novel alternative used for the prevention of acidic leachate from coal refuse.

  1. Sulphate in pregnancy.

    PubMed

    Dawson, Paul A; Elliott, Aoife; Bowling, Francis G

    2015-03-04

    Sulphate is an obligate nutrient for healthy growth and development. Sulphate conjugation (sulphonation) of proteoglycans maintains the structure and function of tissues. Sulphonation also regulates the bioactivity of steroids, thyroid hormone, bile acids, catecholamines and cholecystokinin, and detoxifies certain xenobiotics and pharmacological drugs. In adults and children, sulphate is obtained from the diet and from the intracellular metabolism of sulphur-containing amino acids. Dietary sulphate intake can vary greatly and is dependent on the type of food consumed and source of drinking water. Once ingested, sulphate is absorbed into circulation where its level is maintained at approximately 300 μmol/L, making sulphate the fourth most abundant anion in plasma. In pregnant women, circulating sulphate concentrations increase by twofold with levels peaking in late gestation. This increased sulphataemia, which is mediated by up-regulation of sulphate reabsorption in the maternal kidneys, provides a reservoir of sulphate to meet the gestational needs of the developing foetus. The foetus has negligible capacity to generate sulphate and thereby, is completely reliant on sulphate supply from the maternal circulation. Maternal hyposulphataemia leads to foetal sulphate deficiency and late gestational foetal death in mice. In humans, reduced sulphonation capacity has been linked to skeletal dysplasias, ranging from the mildest form, multiple epiphyseal dysplasia, to achondrogenesis Type IB, which results in severe skeletal underdevelopment and death in utero or shortly after birth. Despite being essential for numerous cellular and metabolic functions, the nutrient sulphate is largely unappreciated in clinical settings. This article will review the physiological roles and regulation of sulphate during pregnancy, with a particular focus on animal models of disturbed sulphate homeostasis and links to human pathophysiology.

  2. Sulphate in Pregnancy

    PubMed Central

    Dawson, Paul A.; Elliott, Aoife; Bowling, Francis G.

    2015-01-01

    Sulphate is an obligate nutrient for healthy growth and development. Sulphate conjugation (sulphonation) of proteoglycans maintains the structure and function of tissues. Sulphonation also regulates the bioactivity of steroids, thyroid hormone, bile acids, catecholamines and cholecystokinin, and detoxifies certain xenobiotics and pharmacological drugs. In adults and children, sulphate is obtained from the diet and from the intracellular metabolism of sulphur-containing amino acids. Dietary sulphate intake can vary greatly and is dependent on the type of food consumed and source of drinking water. Once ingested, sulphate is absorbed into circulation where its level is maintained at approximately 300 μmol/L, making sulphate the fourth most abundant anion in plasma. In pregnant women, circulating sulphate concentrations increase by twofold with levels peaking in late gestation. This increased sulphataemia, which is mediated by up-regulation of sulphate reabsorption in the maternal kidneys, provides a reservoir of sulphate to meet the gestational needs of the developing foetus. The foetus has negligible capacity to generate sulphate and thereby, is completely reliant on sulphate supply from the maternal circulation. Maternal hyposulphataemia leads to foetal sulphate deficiency and late gestational foetal death in mice. In humans, reduced sulphonation capacity has been linked to skeletal dysplasias, ranging from the mildest form, multiple epiphyseal dysplasia, to achondrogenesis Type IB, which results in severe skeletal underdevelopment and death in utero or shortly after birth. Despite being essential for numerous cellular and metabolic functions, the nutrient sulphate is largely unappreciated in clinical settings. This article will review the physiological roles and regulation of sulphate during pregnancy, with a particular focus on animal models of disturbed sulphate homeostasis and links to human pathophysiology. PMID:25746011

  3. Effect of amino acid doping on the growth and ferroelectric properties of triglycine sulphate single crystals

    SciTech Connect

    Raghavan, C.M.; Sankar, R.; Mohan Kumar, R.; Jayavel, R.

    2008-02-05

    Effect of amino acids (L-leucine and isoleucine) doping on the growth aspects and ferroelectric properties of triglycine sulphate crystals has been studied. Pure and doped crystals were grown from aqueous solution by low temperature solution growth technique. The cell parameter values were found to significantly vary for doped crystals. Fourier transform infrared analysis confirmed the presence of functional groups in the grown crystal. Morphology study reveals that amino acid doping induces faster growth rate along b-direction leading to a wide b-plane and hence suitable for pyroelectric detector applications. Ferroelectric domain structure has been studied by atomic force microscopy and hysteresis measurements reveal an increase of coercive field due to the formation of single domain pattern.

  4. Ferric sulphate catalysed esterification of free fatty acids in waste cooking oil.

    PubMed

    Gan, Suyin; Ng, Hoon Kiat; Ooi, Chun Weng; Motala, Nafisa Osman; Ismail, Mohd Anas Farhan

    2010-10-01

    In this work, the esterification of free fatty acids (FFA) in waste cooking oil catalysed by ferric sulphate was studied as a pre-treatment step for biodiesel production. The effects of reaction time, methanol to oil ratio, catalyst concentration and temperature on the conversion of FFA were investigated on a laboratory scale. The results showed that the conversion of FFA reached equilibrium after an hour, and was positively dependent on the methanol to oil molar ratio and temperature. An optimum catalyst concentration of 2 wt.% gave maximum FFA conversion of 59.2%. For catalyst loadings of 2 wt.% and below, this catalysed esterification was proposed to follow a pseudo-homogeneous pathway akin to mineral acid-catalysed esterification, driven by the H(+) ions produced through the hydrolysis of metal complex [Fe(H(2)O)(6)](3+) (aq).

  5. Methanolysis on extracted sapfrom inner and outer part of core oil palm trunk using phosphomolybdic acid and aluminium sulphate

    NASA Astrophysics Data System (ADS)

    Jahar, Noorhasmiera Abu; Mostapha, Marhaini; Wong, Jia Chye; Jaafar, Sharifah Nabihah Syed; Pua, Grace; Zakaria, Sarani; Chia, Chin Hua

    2016-11-01

    Concentration of extracted free sugar in the oil palm trunk from inner and outer part was analysed using High Performance Liquid Chromatography (HPLC). The highest sugar concentration was glucose and total sugar content was higher in the inner part than the outer part. The methanolysis reaction of extracted sapfrom inner and outer part of core oil palm trunk using phosphomolybdic acid and aluminium sulphate was done using methanol as solvent, 2.5 h and at 160°C. In this reaction, conversion of total sugar produced high concentrations of pentanoic acid, 4-oxo-, methyl ester and low 5-hydroxymethylfurfural using aluminium sulphate as catalyst.

  6. Phosphoric acid and copper (II) sulphate as a combined etchant and activator prior to the use of an anaerobic adhesive.

    PubMed

    Ireland, A J; Sherriff, M

    2001-01-01

    Previous work has shown that steel attachments can be bonded to etched human enamel using anaerobic adhesives, following treatment with a solution of 0.05M copper (II) sulphate. The objectives of this experiment were to determine whether simultaneous etching and activation could be performed with a combined solution of o-phosphoric acid and copper (II) sulphate. Stainless steel attachments were bonded to human enamel using an anaerobic adhesive. In each case the enamel was etched and activated using a solution of 37% o-phosphoric acid containing various concentrations of copper (II) sulphate. After bench curing for one hour, the specimens were shear bond tested to failure and the load at debond recorded in each case. Following determination of the optimum copper (II) sulphate concentration the experiment was repeated, but this time the acid was made into a gel using colloidal silica. The effect of rinse time after etching was also investigated with the gel. The results were analysed using mean force to debond (N) and 95% confidence intervals. Kaplan-Meier survival probabilities and log rank tests were also performed. Under the conditions of this experiment the optimum concentration of copper (II) sulphate was found to be 1M. When the acid was made into a gel the optimum rinsing time was found to be 60s. This experiment demonstrates that steel attachments can be bonded to enamel using anaerobic adhesives where the enamel has been simultaneously etched and activated. A combined o-phosphoric acid and copper (II) sulphate solution or gel can be used, but a conventional etch pattern is not produced.

  7. Dietary protocatechuic acid ameliorates dextran sulphate sodium-induced ulcerative colitis and hepatotoxicity in rats.

    PubMed

    Farombi, Ebenezer O; Adedara, Isaac A; Awoyemi, Omolola V; Njoku, Chinonye R; Micah, Gabriel O; Esogwa, Cynthia U; Owumi, Solomon E; Olopade, James O

    2016-02-01

    The present study investigated the antioxidant and anti-inflammatory effects of dietary protocatechuic acid (PCA), a simple hydrophilic phenolic compound commonly found in many edible vegetables, on dextran sulphate sodium (DSS)-induced ulcerative colitis and its associated hepatotoxicity in rats. PCA was administered orally at 10 mg kg(-1) to dextran sulphate sodium exposed rats for five days. The result revealed that administration of PCA significantly (p < 0.05) prevented the incidence of diarrhea and bleeding, the decrease in the body weight gain, shortening of colon length and the increase in colon mass index in DSS-treated rats. Furthermore, PCA prevented the increase in the plasma levels of pro-inflammatory cytokines, markers of liver toxicity and markedly suppressed the DSS-mediated elevation in colonic nitric oxide concentration and myeloperoxidase activity in the treated rats. Administration of PCA significantly protected against colonic and hepatic oxidative damage by increasing the antioxidant status and concomitantly decreased hydrogen peroxide and lipid peroxidation levels in the DSS-treated rats. Moreover, histological examinations confirmed PCA chemoprotection against colon and liver damage. Immunohistochemical analysis showed that PCA significantly inhibited cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expression in the colon of DSS-treated rats. In conclusion, the effective chemoprotective role of PCA in colitis and the associated hepatotoxicity is related to its intrinsic anti-inflammatory and anti-oxidative properties.

  8. Characterization and reactivity assessment of organic substrates for sulphate-reducing bacteria in acid mine drainage treatment.

    PubMed

    Zagury, Gerald J; Kulnieks, Viktors I; Neculita, Carmen M

    2006-08-01

    Acid mine drainage (AMD), which contains high concentrations of sulphate and dissolved metals, is a serious environmental problem. It can be treated in situ by sulphate reducing bacteria (SRB), but effectiveness of the treatment process depends on the organic substrate chosen to supply the bacteria's carbon source. Six natural organic materials were characterized in order to investigate how well these promote sulphate reduction and metal precipitation by SRB. Maple wood chips, sphagnum peat moss, leaf compost, conifer compost, poultry manure and conifer sawdust were investigated in terms of their carbon (TOC, TIC, DOC) and nitrogen (TKN) content, as well as their easily available substances content (EAS). Single substrates, ethanol, a mixture of leaf compost (30% w/w), poultry manure (18% w/w), and maple wood chips (2% w/w), and the same mixture spiked with formaldehyde were then tested in a 70-day batch experiment to evaluate their performance in sulphate reduction and metal removal from synthetic AMD. Metal removal efficiency in batch reactors was as high as 100% for Fe, 99% for Mn, 99% for Cd, 99% for Ni, and 94% for Zn depending on reactive mixtures. Early metal removal (0-12d) was attributed to the precipitation of (oxy)hydroxides and carbonate minerals. The lowest metal and sulphate removal efficiency was found in the reactor containing poultry manure as the single carbon source despite its high DOC and EAS content. The mixture of organic materials was most effective in promoting sulphate reduction, followed by ethanol and maple wood chips, and single natural organic substrates generally showed low reactivity. Formaldehyde (0.015% (w/v)) provided only temporary bacterial inhibition. Although characterization of substrates on an individual basis provided insight on their chemical make-up, it did not give a clear indication of their ability to promote sulphate reduction and metal removal.

  9. Mixture of hyaluronic acid, chondroitin 6 sulphate and dermatan sulphate used to completely regenerate bone in rat critical size defect model.

    PubMed

    Zanchetta, Philippe; Lagarde, Nicole; Uguen, Arnaud; Marcorelles, Pascale

    2012-12-01

    Skeletal bone losses are mainly filled with autologous graft or artificial materials. Osteoblasts are essential to maintain bone homeostasis and bone repair through a matrix synthesis. We have previously demonstrated that adherence and regenerative matrix composition are fundamental to bone healing, even in critical situations. In this work the critical size defect technique was used to evaluate the systemic activity on bone regeneration of a novel mixture of extracellular polysaccharides. A 5mm diameter hole was made in each parietal bone of male Wistar rats. The right parietal bone hole was filled with a mixture of hyaluronic acid, chondroitin 6 sulphate, and dermatan sulphate mixed with 2.5% NaCl solution, while the left hole was left free of material and untreated and considered as control. Twenty-one days after surgery, the holes and surrounding tissues were examined visually, using X-rays, and by histological staining. Using the matrix substitute, bone healing was almost complete after 21 days in the treated hole and always complete in the control side due to some systemic effect. Neovascularization was also observed along with organized trabecular bone on both sides. No abnormal bone growth or connective tissue abnormalities were noted. At the end of the experiment, 95.1% (± 3.2) bone healing (n=20) was observed on the treated side; conversely, healing bone and histological structure were better on the control side.

  10. The LysR-type regulator SftR is involved in soil survival and sulphate ester metabolism in Pseudomonas putida.

    PubMed

    Kahnert, Antje; Mirleau, Pascal; Wait, Robin; Kertesz, Michael A

    2002-04-01

    Sulphate esters make up a large proportion of the available sulphur in agricultural soils, and many pseudomonads can desulphurize a range of aryl- and alkylsulphate esters to provide sulphur for growth. After miniTn5 transposon mutagenesis of Pseudomonas putida S-313, we isolated 19 mutants that were defective in cleavage of the chromogenic sulphate ester 5-bromo-4-chloro-3-indoxylsulphate (X-sulphate). Analysis of these strains revealed that they carried independent insertions in a gene cluster that comprised genes for a sulphate ester/sulphonate transporter (atsRBC) a LysR-type regulator (sftR), an oxygenolytic alkylsulphatase (atsK), an arylsulphotransferase (astA) and a putative TonB-dependent receptor (sftP). The SftP protein was localized in the outer membrane, and the arylsulfphotransferase was identified as an intracellular enzyme. Expression of sftR was repressed in the presence of inorganic sulphate, and the sftR gene was required for the expression of atsBC, atsRK and sftP-astA. An sftR mutant was unable to grow with aryl- or alkylsulphate esters in laboratory media and showed significantly reduced survival compared with the parent strain during incubation in Danish agricultural and grassland soils. This effect suggests that sulphate esters are an important sulphur source for microbes in aerobic soils and highlights the importance of the microbial population in the soil sulphur cycle.

  11. The micronutrient supplements, zinc sulphate and folic acid, did not ameliorate sperm functional parameters in oligoasthenoteratozoospermic men.

    PubMed

    Raigani, M; Yaghmaei, B; Amirjannti, N; Lakpour, N; Akhondi, M M; Zeraati, H; Hajihosseinal, M; Sadeghi, M R

    2014-01-01

    We investigated the effects of folic acid and zinc sulphate supplementation on the improvement of sperm function in subfertile oligoasthenoteratozoospermic (OAT) men. Eighty-three OAT men participated in a 16-week intervention randomised, double-blind clinical trial with daily treatment of folic acid (5 mg day(-1) ) and zinc sulphate (220 mg day(-1) ), or placebo. Before and after treatment, semen and blood samples were obtained for determining sperm concentration, motility, and morphology, sperm viability, sperm mitochondrial function, sperm chromatin status using toluidine blue, aniline blue, acridine orange and chromomycin A3 staining; and semen and blood folate, zinc, B12 , total antioxidant capacity (TAC) and malondialdehyde (MDA) concentrations. Sperm concentration (×10(6)  ml(-1) ) increased in subfertile men receiving the combined treatment of folic acid and zinc sulphate and also in the group receiving only folic acid treatment; however, it was not statistically significant (P = 0.056 and P = 0.05, respectively). Sperm chromatin integrity (%) increased significantly in subfertile men receiving only zinc sulphate treatment (P = 0.048). However, this improvement in sperm quality was not significant after adjusting placebo effect. This study showed that zinc sulphate and folic acid supplementation did not ameliorate sperm quality in infertile men with severely compromised sperm parameters, OAT. Male infertility is a multifactorial disorder, and also nutritional factors play an important role in results of administration of supplementation on sperm parameters. However, these results should be confirmed by multiple studies in larger populations of OAT men. © 2013 Blackwell Verlag GmbH.

  12. Modification of di- and tetrasaccharides from shark cartilage keratan sulphate by refined anhydromethanolic hydrochloric acid-treatments and evaluation of their specific desulphation.

    PubMed

    Kariya, Yutaka; Watabe, Shugo; Mochizuki, Hideo; Imai, Kyoko; Kikuchi, Hiroshi; Suzuki, Kiyoshi; Kyogashima, Mamoru; Ishii, Tadashi

    2003-05-01

    Highly sulphated keratan di- and tetrasaccharides were prepared from keratan sulphate (KS) of shark cartilage by enzymatic digestion with keratanase II and subsequent chromatography. The tetrasaccharide fraction carrying four sulphate groups was completely desulphated by 100 mM anhydromethanolic hydrochloric acid (MeOH-HCl) treatment at room temperature for 16 h. The conditions for the desulphation reaction by MeOH-HCl treatment were examined using sulphated keratan di- and tetrasaccharides as substrates by means of reversed phase high performance liquid chromatography (HPLC) and/or capillary electrophoresis, followed by the preparation of partially desulphated keratan oligosaccharides. Sulphate substitution patterns of monosulphated keratan disaccharide and trisulphated keratan tetrasaccharide were evaluated by methylation analysis. The results suggested that 6-O-sulphate groups of Gal moieties are cleaved faster than those of GlcNAc moieties under the present conditions adopted for the MeOH-HCl treatment of KS-derived oligosaccharides.

  13. Iminodiacetic acid doped ferroelectric triglycine sulphate crystal: Crystal growth and characterization

    NASA Astrophysics Data System (ADS)

    Rai, Chitharanjan; Narayana Moolya, B.; Dharmaprakash, S. M.

    2011-01-01

    Single crystals of iminodiacetic acid (HN(CH 2COOH) 2) doped triglycine sulphate (IDATGS) crystals have been grown from aqueous solution containing 1-10 mol% of iminodiacetic acid at constant temperature by slow evaporation technique. The effects of different amounts of doping entities on the growth habit have been investigated. X-ray powder diffraction pattern for pure and doped TGS was collected to determine the lattice parameters. The grown crystals were subjected to Fourier transform infrared (FTIR) spectroscopy studies to find the presence of various functional groups qualitatively. The dielectric permittivity has been studied as a function of temperature. An increase in the transition temperature (49.2-49.7 °C) of IDATGS crystals is observed. The dielectric constant ( ε‧ max) of IDATGS crystals vary in the range 922-2410 compared to pure TGS ( Tc=49.12 °C and ε‧ max=3050). Curie Weiss constants Cp and Cf in the paraelectric and ferroelectric phases were determined. The transition temperature ( Tc) is found to decrease with increase in dopant concentration. P- E hysteresis studies show the presence of internal bias field in the crystal. Piezoelectric measurements were also carried out at room temperature. Domain patterns on b-cut plates were observed using scanning electron microscope. The micro hardness studies reveal that the doped crystals are harder than the pure TGS crystals. The low dielectric constant, higher transition temperature, internal bias field and hardness suggest that IDATGS crystals could be a potential material for IR detectors.

  14. Effects of dietary chromium chloride, nicotinic acid and copper sulphate on meat of broilers.

    PubMed

    Javed, M T; Ellahi, M; Abbas, N; Yasmin, R; Mazhar, M

    2010-06-01

    1. Combinations of chromium and copper were added to the diet to assess their effects on broiler meat characteristics. 2. For this purpose 175 one-day-old broiler chicks were divided into 7 equal groups and were given treatment feeds containing copper sulphate, chromium chloride and nicotinic acid in different combinations. 3. The study was carried out for 5 weeks and samples were collected at the end of 15, 29 and 35 d of treatment and at 42 d after a withdrawal period of one week. 4. Cholesterol content had decreased significantly in breast meat at d 29 in all treatment groups. In thigh meat, it decreased significantly at d 29 in groups receiving two concentrations of chromium + two concentrations of copper. Cholesterol content remained lower even after withholding the treatment for one week. 5. Crude fat content decreased significantly in breast meat in all treatment groups. In thigh meat, at d 29, a significant reduction in crude fat was observed only in birds receiving low chromium and high copper. 6. Crude protein at d 29 increased significantly in breast meat of birds receiving low chromium and high copper, and low or high chromium, while it decreased significantly in treatment groups after withholding the treatment. In thigh meat, at d 29, it increased significantly in treatment groups but decreased significantly after withholding the treatment. 7. It was concluded that chromium and copper, along with nicotinic acid, have modulating effects on broiler meat under tropical conditions.

  15. An integrated algal sulphate reducing high rate ponding process for the treatment of acid mine drainage wastewaters.

    PubMed

    Rose, P D; Boshoff, G A; van Hille, R P; Wallace, L C; Dunn, K M; Duncan, J R

    1998-01-01

    Acid mine drainage pollution may be associated with large water volume flows and exceptionally long periods of time over which the drainage may require treatment. While the use and role of sulphate reducing bacteria has been demonstrated in active treatment systems for acid mine drainage remediation, reactor size requirement and the cost and availability of the carbon and electron donor source are factors which constrain process development. Little attention has focussed on the use of waste stabilisation ponding processes for acid mine drainage treatment. Wastewater ponding is a mature technology for the treatment of large water volumes and its use as a basis for appropriate reactor design for acid mine drainage treatment is described including high rates of sulphate reduction and the precipitation of metal sulphides. Together with the co-disposal of organic wastes, algal biomass is generated as an independent carbon source for SRB production. Treatment of tannery effluent in a custom-designed high rate algal ponding process, and its use as a carbon source in the generation and precipitation of metal sulphides, has been demonstrated through piloting to the implementation of a full-scale process. The treatment of both mine drainage and zinc refinery wastewaters are reported. A complementary role for microalgal production in the generation of alkalinity and bioadsorptive removal of metals has been utilised and an Integrated 'Algal Sulphate Reducing Ponding Process for the Treatment of Acidic and Metal Wastewaters' (ASPAM) has been described.

  16. Impact of organic nano-vesicles in soil: The case of sodium dodecyl sulphate/didodecyl dimethylammonium bromide.

    PubMed

    Gavina, A; Bouguerra, S; Lopes, I; Marques, C R; Rasteiro, M G; Antunes, F; Rocha-Santos, T; Pereira, R

    2016-03-15

    Aiming at contributing new insights into the effects of nanomaterials (NMs) in the terrestrial ecosystem, this study evaluated the impacts of organic nano-vesicles of sodium dodecyl sulphate/didodecyl dimethylammonium bromide (SDS/DDAB) on the emergence and growth of plant seeds, and on the avoidance and reproduction of soil invertebrates. For this purpose several ecotoxicological assays were performed with different test species (terrestrial plants: Zea mays, Avena sativa, Brassica oleracea and Lycopersicon esculentum; soil invertebrates: Eisenia andrei and Folsomia candida). A wide range of SDS/DDAB concentrations were tested, following standard protocols, and using the standard OECD soil as a test substrate (5% of organic matter). The aqueous suspensions of SDS/DDAB, used to spike the soils, were characterised by light scattering techniques for hydrodynamic size of the vesicles, aggregation index, polydispersity index, zeta potential and surface charge. The SDS/DDAB concentrations in the test soil were analysed by HPLC-UV at the end of the assays. Invertebrate species were revealed to be sensitive to nano-SDS/DDAB upon immediate exposure to freshly spiked soils. However, the degradation of SDS/DDAB nano-vesicles in the soil with time prevented the occurrence of significant reproduction effects on soil invertebrates. Plants were not particularly sensitive to SDS/DDAB, except B. oleracea (at concentrations above 375 mg kg(-1)dw). The results gathered in this study allowed a preliminary determination of a risk limit to nano-SDS/DDAB. The low toxicity of SDS/DDAB nano-vesicles could be explained by its high and fast degradation in the soil. The soil microbial community could have an important role in the fate of this NM, thus it is of remarkable importance to improve this risk limit by taking into account specific data addressing this community.

  17. Removal of sulphates acidity and iron from acid mine drainage in a bench scale biochemical treatment system.

    PubMed

    Prasad, D; Henry, J G

    2009-02-01

    The focus of this study was to develop a simple biochemical system to treat acid mine drainage for its safe disposal. Recovery and reuse of the metals removed were not considered. A three-step process for the treatment of acid mine drainage (AMD), proposed earlier, separates sulphate reducing activity from metal precipitation units and from a pH control system. Following our earlier work on the first step (biological reactor), this paper examines the second step (i.e. chemical reactor). The objectives of this study were: (1) to determine the increase in pH and the reduction of iron in the chemical reactor for different proportions of simulated AMD, and (2) to assess the capability of the chemical reactor. A series of experiments was conducted to study the effects of addition of alkaline sulphidogenic liquor (ASL) derived from a batch sulphidogenic biological reactor (operating with activated sludge and a COD/SO4 ratio of 1.6) on the simulated AMD characteristics. At 60-minute contact time, addition of 30% ASL (pH of 7.60-7.76) to the chemical reactor with 70% AMD (pH of 1.65-2.02), increased the pH of the AMD to 6.57 and alkalinity from 0 to 485 mg l(-1) as CaCO3, respectively and precipitated about 97% of the iron present in the simulated AMD. Others have demonstrated that metals in mine drainage can be precipitated by bacterial sulphate reduction. In this study, iron, a common and major component of mine drainage was used as a surrogate for metals in general. The results indicate the feasibility of treating AMD by an engineered sulphidogenic anaerobic reactor followed by a chemical reactor and that our three-step biochemical process has important advantages over other conventional AMD treatment systems.

  18. Citric Acid Addition to Controlling Crystallization of Barium Sulphate (BaSO4) in Pipes through Ba2+ Concentration Variation in the Solution

    NASA Astrophysics Data System (ADS)

    Ivanto, G.; Fatra, F.; Dera, N. S.; Muryanto, S.; Bayuseno, A. P.

    2017-05-01

    The scale of barium sulphate (BaSO4) is common scale for mineral deposit that found in the offshore oil and gas exploitation. This scale is related with precipitation and grown of mineral deposit on the pipelines surface. Therefore, it results in blockage at the pipe. This paper presents the experimental scaling of barium sulphate in the laminar flow. The barium sulphate solution was prepared by mixing an equimolar solution of barium chloride (BaCl2) and sodium sulphate (Na2SO4). The flow rate is 40 ml/min at temperature of 50 °C. The solutions added by citric acid (C6H8O7) with variation concentration of 0 ppm, 5 ppm, and 10 ppm. The crystallization of barium sulphate was measured by using the conductivity meters. The barite crytals were dried and characterized by using SEM/EDX and XRD. The SEM Results show that the morphology of Barite scale was change in the presence of citric acid. The mineral of barium sulphate was pure barite based on the XRD phase analysis. The presence of citric acid clearly inhibit the crystallization of barium sulphate.

  19. Structural analysis of aqueous ferrofluids with cobalt ferrite particles stabilized with lauric acid and sodium n-dodecyl sulphate

    NASA Astrophysics Data System (ADS)

    Balasoiu-Gaina, A.-M.; Balasoiu, M.; Ivankov, O.; Soloviov, D.; Lysenko, S.; Stan, C.; Lupu, N.; Creanga, D.; Kuklin, A.

    2017-05-01

    Small angle neutron scattering (SANS) experiment on CoFe2O4/lauric acid/sodium dodecyl sulphate/H2O ferrofluid was performed at the time-of-flight YuMO spectrometer. Concentration effects on the structure variation of the investigated ferrofluid are presented. Using the zero concentration approximation, the structure factors of samples with different concentration were determined. It was shown that the structure factor of values higher than 1 is present in samples with particle volume concentration equal and greater than 0.5%.

  20. Acidic deposition and soil processes

    SciTech Connect

    Newton, R.M.; April, R.H.

    1985-08-01

    The results of the Integrated Lake-Watershed Acidification Study (ILWAS) show that the sensitivity of a watershed to surface water acidification is determined by the flow paths of water through the terrestrial system. If the water infiltrates through the soils into the groundwater system, acid neutralization occurs through weathering reactions involving minerals in the soils and till. Runoff and shallow interflow result in acid surface waters. Flow paths are determined in the ILWAS watersheds by the thickness of the glacial till. Complete neutralization can occur even in areas underlain by sensitive bedrock if the flow path through the mineral horizons is long enough. This appears to hold even in areas outside of the Adirondacks. 11 references, 5 figures.

  1. Spatial separation of individual substances in effloresced crystals of ternary ammonium sulphate/dicarboxylic acid/water aerosols.

    PubMed

    Treuel, Lennart; Sandmann, Alice; Zellner, Reinhard

    2011-04-18

    This work examines the crystals resulting from the efflorescence of internally mixed aqueous aerosols comprising ammonium sulphate and different dicarboxylic acids. Most studies on the deliquescence of aerosols use previously effloresced aerosols in their experiments. However, during efflorescence a highly supersaturated solution crystallises in a kinetically controlled way unlike the case of thermodynamically controlled crystallisation. Herein the distribution of individual substances within the effloresced crystals is investigated using Raman scanning experiments. The data presented show an intriguingly complex behaviour of these ternary and quarternary aerosols. A spatial separation of substances in the crystals resulting from the efflorescence of previously internally mixed ternary salt/dicarboxylic acid/water aerosol droplets is demonstrated and mechanistic aspects are discussed.

  2. The effect of nitric acid (HNO3) on growth, spectral, thermal and dielectric properties of triglycine sulphate (TGS) crystal.

    PubMed

    Parimaladevi, R; Sekar, C; Krishnakumar, V

    2010-02-01

    The effect of nitric acid (HNO(3)) addition on the growth of triglycine sulphate (TGS) crystal has been studied from the aqueous solution for various concentrations of nitric acid. Significant changes in the crystal size and morphology have been observed in all the grown samples. Single crystal and powder X-ray diffraction analyses confirm the structure and cell parameter values of pure and HNO(3) doped TGS crystals. FT-Raman and FTIR spectra confirm the characteristics absorption bands of pure and HNO(3) doped TGS crystals. The composition of TGS crystals have been confirmed by CHNS analysis. Physical properties such as thermal, dielectric and mechanical studies have been performed for the pure and HNO(3) doped TGS crystals. The dielectric constants of the crystals have been studied as a function of frequency. The results suggest that the HNO(3) is doped into TGS crystal and that the doping increases its dielectric constant.

  3. Stratification of Metal and Sulphate Loads in Acid Mine Drainage Receiving Water Dams - Variables Regionalization by Cluster Analysis.

    PubMed

    Grande, J A; de la Torre, M L; Valente, T; Fernández, J P; Borrego, J; Santisteban, M; Cerón, J C; Sánchez-Rodas, D

    2015-07-01

    The Sancho Reservoir (Iberian Pyrite Belt, SW Spain) is nourished by the waters of the river Meca, which is affected by acid mine drainage (AMD) processes from the abandoned Tharsis mine. The aim of the present work is to study the hydrochemical variations in this reservoir, in order to define potential stratification processes in metal load and sulphates. A stratified sampling from the surface, with one meter deep intervals to the bottom of the dam, was performed. The results show a clear stratification of temperature, pH, electric conductivity, dissolved oxygen, metal and sulphate loads associated with depth. There is an increase of metal loads at the bottom of the reservoir, though previous studies only detect iron. The proximity between pH and aluminium suggests that water chemistry is strongly influenced by aluminium precipitation processes. This indicates the buffer effect that aluminium exercises, which precipitates as amorphous or low crystalline phases, introducing hydrogen ions to the system, while alkalinity input tends to raise pH.

  4. Thermodynamics of sodium dodecyl sulphate-salicylic acid based micellar systems and their potential use in fruits postharvest.

    PubMed

    Cid, A; Morales, J; Mejuto, J C; Briz-Cid, N; Rial-Otero, R; Simal-Gándara, J

    2014-05-15

    Micellar systems have excellent food applications due to their capability to solubilise a large range of hydrophilic and hydrophobic substances. In this work, the mixed micelle formation between the ionic surfactant sodium dodecyl sulphate (SDS) and the phenolic acid salicylic acid have been studied at several temperatures in aqueous solution. The critical micelle concentration and the micellization degree were determined by conductometric techniques and the experimental data used to calculate several useful thermodynamic parameters, like standard free energy, enthalpy and entropy of micelle formation. Salicylic acid helps the micellization of SDS, both by increasing the additive concentration at a constant temperature and by increasing temperature at a constant concentration of additive. The formation of micelles of SDS in the presence of salicylic acid was a thermodynamically spontaneous process, and is also entropically controlled. Salicylic acid plays the role of a stabilizer, and gives a pathway to control the three-dimensional water matrix structure. The driving force of the micellization process is provided by the hydrophobic interactions. The isostructural temperature was found to be 307.5 K for the mixed micellar system. This article explores the use of SDS-salicylic acid based micellar systems for their potential use in fruits postharvest.

  5. Preparation and characterization of a new gellan gum and sulphated hyaluronic acid hydrogel designed for epidural scar prevention.

    PubMed

    Cencetti, Claudia; Bellini, Davide; Longinotti, Cristina; Martinelli, Andrea; Matricardi, Pietro

    2011-02-01

    Postsurgical adhesions are a common problem in clinical practice, causing nerve compression, pain and discomfort. A new hydrogel based on gellan gum and sulphated hyaluronic acid was synthesized, with the aim to create an effective barrier for epidural scar formation. Physico-chemical properties of the gel were analyzed, and preliminary biocompatibility data (i.e. cytotoxicity) have been collected in view of its potential clinical use. The characterization of the new material demonstrated that the hydrogel, due to its high-viscosity, could effectively act as a barrier with a long in situ residence time. In addition, the hydrogel can be easily extruded from a syringe and its structure exhibits excellent stabilizing properties. Furthermore, biological assays showed that this gel is suitable for further preclinical development.

  6. Characterization and activity studies of highly heavy metal resistant sulphate-reducing bacteria to be used in acid mine drainage decontamination.

    PubMed

    Martins, Mónica; Faleiro, M Leonor; Barros, Raúl J; Veríssimo, A Raquel; Barreiros, M Alexandra; Costa, M Clara

    2009-07-30

    Biological treatment with sulphate-reducing bacteria (SRB) has been considered as the most promising alternative for acid mine drainage (AMD) decontamination. Normally, these wastewaters contain high concentrations of sulphate and heavy metals, so the search for SRB highly resistant to metals is extremely important for the development of a bioremediation technology. A SRB consortium resistant to high concentrations of heavy metals (Fe, Cu and Zn), similar to those typically present in AMD, was obtained among several environmental samples, from a wastewater treatment plant. The phylogenetic analysis of the dsr gene sequence revealed that this consortium contains species of SRB affiliated to Desulfovibrio desulfuricans and Desulfobulbus rhabdoformis. The results show that the presence of usually lethal concentrations of Fe (400mg/L), Zn (150 mg/L) and Cu (80 mg/L) is not toxic for the sulphate-reducing bacteria present in this sample. As a consequence, a very good efficiency in terms of sulphate reduction and metals removal was obtained. Both ethanol and lactate can be used by this inoculum as carbon source. With the other samples tested sulphate reduction was inhibited by the presence of copper and zinc. This highly metal resistant consortium will be used to inoculate a bioreactor to carry out AMD decontamination.

  7. Production of biodiesel from mixed waste vegetable oil using an aluminium hydrogen sulphate as a heterogeneous acid catalyst.

    PubMed

    Ramachandran, Kasirajan; Sivakumar, Pandian; Suganya, Tamilarasan; Renganathan, Sahadevan

    2011-08-01

    Al(HSO(4))(3) heterogeneous acid catalyst was prepared by the sulfonation of anhydrous AlCl(3). This catalyst was employed to catalyze transesterification reaction to synthesis methyl ester when a mixed waste vegetable oil was used as feedstock. The physical and chemical properties of aluminum hydrogen sulphate catalyst were characterized by scanning electron microscopy (SEM) measurements, energy dispersive X-ray (EDAX) analysis and titration method. The maximum conversion of triglyceride was achieved as 81 wt.% with 50 min reaction time at 220°C, 16:1 molar ratio of methanol to oil and 0.5 wt.% of catalyst. The high catalytic activity and stability of this catalyst was related to its high acid site density (-OH, Brönsted acid sites), hydrophobicity that prevented the hydration of -OH group, hydrophilic functional groups (-SO(3)H) that gave improved accessibility of methanol to the triglyceride. The fuel properties of methyl ester were analyzed. The fuel properties were found to be observed within the limits of ASTM D6751.

  8. Lectin affinity chromatography of articular cartilage fibromodulin: Some molecules have keratan sulphate chains exclusively capped by α(2-3)-linked sialic acid.

    PubMed

    Lauder, Robert M; Huckerby, Thomas N; Nieduszynski, Ian A

    2011-10-01

    Fibromodulin from bovine articular cartilage has been subjected to lectin affinity chromatography by Sambucus nigra lectin which binds α(2-6)- linked N-acetylneuraminic acid, and the structure of the keratan sulphate in the binding and non-binding fractions examined by keratanase II digestion and subsequent high pH anion exchange chromatography. It has been confirmed that the keratan sulphate chains attached to fibromodulin isolated from bovine articular cartilage may have the chain terminating N-acetylneuraminic acid residue α(2-3)- or α(2-6)-linked to the adjacent galactose residue. Although the abundance of α(2-6)-linked N-acetylneuraminic acid (ca. 22%) is such that this could cap one of the four chains in almost all fibromodulin molecules, it was found that ca. 34% of the fibromodulin proteoglycan molecules from bovine articular cartilage were capped exclusively with α(2-3)-linked N-acetylneuraminic acid. The remainder of the fibromodulin proteoglycans, which bound to the lectin had a mixture of α(2-3)- and α(2-6)-linked N-acetylneuraminic acid capping structures. The keratan sulphates attached to fibromodulin molecules capped exclusively with α(2-3)- linked N-acetylneuraminic acid were found to have a higher level of galactose sulphation than those from fibromodulin with both α(2-3)- and α(2-6)-linked N-acetylneuraminic acid caps, which bound to the Sambucus nigra lectin. In addition, both pools contained chains of similar length (ca. 8-9 disaccharides). Both also contained α(1-3)-linked fucose, showing that this feature does not co-distribute with α(2-6)-linked N-acetylneuraminic acid, although these two features are present only in mature articular cartilage. These data show that there are discrete populations of fibromodulin within articular cartilage, which may have differing impacts upon tissue processes.

  9. Designer, acidic biochar influences calcareous soil characteristics

    USDA-ARS?s Scientific Manuscript database

    An acidic (pH 5.8) biochar was created using a low pyrolysis temperature (350 degrees celsius) and steam activation to potentially improve the soil physicochemical status of an eroded calcareous soil. Biochar was added at 0, 1, 2, and 10 percent (by weight) to an eroded Portneuf soil (coarse-silty,...

  10. The role of soil microbes in plant sulphur nutrition.

    PubMed

    Kertesz, Michael A; Mirleau, Pascal

    2004-08-01

    Chemical and spectroscopic studies have shown that in agricultural soils most of the soil sulphur (>95%) is present as sulphate esters or as carbon-bonded sulphur (sulphonates or amino acid sulphur), rather than inorganic sulphate. Plant sulphur nutrition depends primarily on the uptake of inorganic sulphate. However, recent research has demonstrated that the sulphate ester and sulphonate-pools of soil sulphur are also plant-bioavailable, probably due to interconversion of carbon-bonded sulphur and sulphate ester-sulphur to inorganic sulphate by soil microbes. In addition to this mineralization of bound forms of sulphur, soil microbes are also responsible for the rapid immobilization of sulphate, first to sulphate esters and subsequently to carbon-bound sulphur. The rate of sulphur cycling depends on the microbial community present, and on its metabolic activity, though it is not yet known if specific microbial species or genera control this process. The genes involved in the mobilization of sulphonate- and sulphate ester-sulphur by one common rhizosphere bacterium, Pseudomonas putida, have been investigated. Mutants of this species that are unable to transform sulphate esters show reduced survival in the soil, indicating that sulphate esters are important for bacterial S-nutrition in this environment. P. putida S-313 mutants that cannot metabolize sulphonate-sulphur do not promote the growth of tomato plants as the wild-type strain does, suggesting that the ability to mobilize bound sulphur for plant nutrition is an important role of this species.

  11. Aluminium-phosphate-sulphate minerals as markers of sustained acidic conditions during the Permian-Triassic transition in E Iberia.

    NASA Astrophysics Data System (ADS)

    Borruel-Abadía, Violeta; Belén Galán-Abellán, Ana; Barrenechea, José F.; De la Horra, Raúl; Luque, Francisco Javier; Alonso-Azcárate, Jacinto; López-Gómez, José

    2016-04-01

    Strontium-rich hydrated Aluminium phosphate-sulphate (APS) minerals are markers of an acidic formation environment due to their precipitation at low pH conditions. However, their small size (0.5-6 μm), low concentrations, and optical properties represent the main problems to quantify these minerals. This study provides quantitative data on APS mineral concentrations for the Late Permian and Early-Middle Triassic in different continental sections of East Iberia. By quantifying APS minerals useful insight can be obtained into the environmental conditions that prevailed during the biotic crisis of the PTB and during the later recovery of life at the end of the Early Triassic. For that, a quantification method based on element mapping of randomly selected areas of thin sections on the electron microprobe is proposed, with relative errors ranging from 5.6% to 11.7%. The results are considered on a detailed petrographic, sedimentological, and palaeontological framework, and compared with other geochemical. Thus, in the first sedimentary record after the Permian-Triassic boundary (Olenekian), it has been possible to correlate relatively high concentration levels of APS minerals with the lack of signs of living organisms. Our findings suggest a long period of sustained acidic conditions followed by an environmental change that permitted the recovery of life, as reflected by lower APS mineral contents detected at the end of the Spathian and the first presence of bioturbation, paleosols, footprints, and plant remains. Early Anisian acidic episodes were much more sporadic than those during the Olenekian deposition, in which APS mineral concentrations were an order of magnitude higher. This fact would indicate punctual acidic conditions still during the beginning of the Anisian. Based on these results, this method is proposed as a tool for addressing environmental changes that took place during the Permian-Triassic transition in continental environments.

  12. Influences of soil acidity on Streptomyces populations inhabiting forest soils.

    PubMed Central

    Hagedorn, C

    1976-01-01

    The Streptomyces populations inhabiting five acidic forest soils were examined. It was found that lowering the pH of a medium selective for streptomycetes (starch-casein agar) to the pH of the particular soil horizon being plated influenced both the total numbers and types of streptomycetes that were isolated from the soils examined in this study. On the acidified medium both the numbers of streptomycetes and the percentage of total bacteria on the plates represented by streptomycetes increased (as compared with the same medium with a pH of 7.2). These differences were greatest on the isolations from the most acid soils. The largest concentrations of streptomycetes were found in the surface horizon (0 to 15 cm) and the litter layer immediately over the surface mineral horizon. Acidity tolerance tests demonstrated that random samplings of isolates contained acidophilic, neutrophilic, and acidoduric strains, with the largest numbers of acidophiles being found on the acidified media from the most acid soils. There were no differences between overall utilization of selected carbohydrates among the isolates taken from either the neutral or acidic media, although a larger proportion of the acid media isolates produced acid from the carbohydrates. Evidence is presented which indicates that different types of streptomycetes were isolated on the acid media, and possible reasons for the presence of these acid-tolerant populations are discussed. PMID:10835

  13. The Effect of Chondroitin Sulphate and Hyaluronic Acid on Chondrocytes Cultured within a Fibrin-Alginate Hydrogel.

    PubMed

    Little, Christopher J; Kulyk, William M; Chen, Xiongbiao

    2014-09-18

    Osteoarthritis is a painful degenerative joint disease that could be better managed if tissue engineers can develop methods to create long-term engineered articular cartilage tissue substitutes. Many of the tissue engineered cartilage constructs currently available lack the chemical stimuli and cell-friendly environment that promote the matrix accumulation and cell proliferation needed for use in joint cartilage repair. The goal of this research was to test the efficacy of using a fibrin-alginate hydrogel containing hyaluronic acid (HA) and/or chondroitin sulphate (CS) supplements for chondrocyte culture. Neonatal porcine chondrocytes cultured in fibrin-alginate hydrogels retained their phenotype better than chondrocytes cultured in monolayer, as evidenced by analysis of their relative expression of type II versus type I collagen mRNA transcripts. HA or CS supplementation of the hydrogels increased matrix glycosaminoglycan (GAG) production during the first week of culture. However, the effects of these supplements on matrix accumulation were not additive and were no longer observed after two weeks of culture. Supplementation of the hydrogels with CS or a combination of both CS and HA increased the chondrocyte cell population after two weeks of culture. Statistical analysis indicated that the HA and CS treatment effects on chondrocyte numbers may be additive. This research suggests that supplementation with CS and/or HA has positive effects on cartilage matrix production and chondrocyte proliferation in three-dimensional (3D) fibrin-alginate hydrogels.

  14. A Biphasic Calcium Sulphate/Hydroxyapatite Carrier Containing Bone Morphogenic Protein-2 and Zoledronic Acid Generates Bone.

    PubMed

    Raina, Deepak Bushan; Isaksson, Hanna; Hettwer, Werner; Kumar, Ashok; Lidgren, Lars; Tägil, Magnus

    2016-05-18

    In orthopedic surgery, large amount of diseased or injured bone routinely needs to be replaced. Autografts are mainly used but their availability is limited. Commercially available bone substitutes allow bone ingrowth but lack the capacity to induce bone formation. Thus, off-the-shelf osteoinductive bone substitutes that can replace bone grafts are required. We tested the carrier properties of a biphasic, calcium sulphate and hydroxyapatite ceramic material, containing a combination of recombinant human bone morphogenic protein-2 (rhBMP-2) to induce bone, and zoledronic acid (ZA) to delay early resorption. In-vitro, the biphasic material released 90% of rhBMP-2 and 10% of ZA in the first week. No major changes were found in the surface structure using scanning electron microscopy (SEM) or in the mechanical properties after adding rhBMP-2 or ZA. In-vivo bone formation was studied in an abdominal muscle pouch model in rats (n = 6/group). The mineralized volume was significantly higher when the biphasic material was combined with both rhBMP-2 and ZA (21.4 ± 5.5 mm(3)) as compared to rhBMP-2 alone (10.9 ± 2.1 mm(3)) when analyzed using micro computed tomography (μ-CT) (p < 0.01). In the clinical setting, the biphasic material combined with both rhBMP-2 and ZA can potentially regenerate large volumes of bone.

  15. Effects of arachidonic acid intake on inflammatory reactions in dextran sodium sulphate-induced colitis in rats.

    PubMed

    Naito, Yukiko; Ji, Xu; Tachibana, Shigehiro; Aoki, Satoko; Furuya, Mami; Tazura, Yoshiyuki; Miyazawa, Daisuke; Harauma, Akiko; Moriguchi, Toru; Nagata, Tomoko; Iwai, Naoharu; Ohara, Naoki

    2015-09-14

    The aim of this study was to investigate the effects of the administration of oral arachidonic acid (AA) in rats with or without dextran sulphate sodium (DSS)-induced inflammatory bowel disease. Male Wistar rats were administered AA at 0, 5, 35 or 240 mg/kg daily by gavage for 8 weeks. Inflammatory bowel disease was induced by replacing drinking water with 3 % DSS solution during the last 7 d of the AA dosing period. These animals passed loose stools, diarrhoea and red-stained faeces. Cyclo-oxygenase-2 concentration and myeloperoxidase activity in the colonic tissue were significantly increased in the animals given AA at 240 mg/kg compared with the animals given AA at 0 mg/kg. Thromboxane B2 concentration in the medium of cultured colonic mucosae isolated from these groups was found to be dose-dependently increased by AA, and the increase was significant at 35 and 240 mg/kg. Leukotriene B4 concentration was also significantly increased and saturated at 5 mg/kg. In addition, AA at 240 mg/kg promoted DSS-induced colonic mucosal oedema with macrophage infiltration. In contrast, administration of AA for 8 weeks, even at 240 mg/kg, showed no effects on the normal rats. These results suggest that in rats with bowel disease AA metabolism is affected by oral AA, even at 5 mg/kg per d, and that excessive AA may aggravate inflammation, whereas AA shows no effects in rats without inflammatory bowel disease.

  16. Acid rain on Acid soil: a new perspective.

    PubMed

    Krug, E C; Frink, C R

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  17. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  18. Retention of metal and sulphate ions from acidic mining water by anionic nanofibrillated cellulose.

    PubMed

    Venäläinen, Salla H; Hartikainen, Helinä

    2017-12-01

    We carried out an adsorption experiment to investigate the ability of anionic nanofibrillated cellulose (NFC) to retain metal and SO4(2-) ions from authentic highly acidic (pH3.2) mining water. Anionic NFC gels of different consistencies (1.1-%, 1.4-% and 1.8-% w/w) were allowed to react for 10min with mining water, after which NFC-induced changes in the metal and SO4(2-) concentrations of the mining water were determined. The sorption capacities of the NFC gels were calculated as the difference between the element concentrations in the untreated and NFC-treated mining water samples. All the NFCs efficiently co-adsorbed both metals and SO4(2-). The retention of metals was concluded to take place through formation of metal-ligand complexes. The reaction between the NFC ligand and the polyvalent cations renders the cellulose nanofibrils positively charged and, thus, able to retain SO4(2-) electrostatically. Adsorption capacity of the NFC gels substantially increased upon decreasing DM content as a result of the dilution-induced weakening of the mutual interactions between individual cellulose nanofibrils. This outcome reveals that the dilution of the NFC gel not only increases its purification capacity but also reduces the demand for cellulosic raw material. These results suggest that anionic NFC made of renewable materials serves as an environmentally sound and multifunctional purification agent for acidic multimetal mining waters or AMDs of high ionic strength. Unlike industrial minerals traditionally used to precipitate valuable metals from acidic mining effluents before their permanent disposal from the material cycle, NFC neither requires mining of unrenewable raw materials nor produces inorganic sludges. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Reducing mechanical activation-induced amorphisation of salbutamol sulphate by co-processing with selected carboxylic acids.

    PubMed

    Curtin, Vincent; Amharar, Youness; Gallagher, Kieran H; Corcoran, Sarah; Tajber, Lidia; Corrigan, Owen I; Healy, Anne Marie

    2013-11-18

    The unintentional generation of amorphous character in crystalline active pharmaceutical ingredients (APIs) is an adverse consequence of mechanical activation during dosage form manufacture. In this study, we assess and compare the ability of low glass transition temperature (Tg) dicarboxylic acids to mitigate amorphisation of a model API, salbutamol sulphate (SS), on both co-milling and co-mixing. SS processed alone, as well as co-milled and co-mixed composites of the API with glutaric acid (GA), adipic acid (AA) and pimelic acid (PA) were characterised by powder X-ray diffraction (pXRD), differential scanning calorimetry (DSC) and dynamic vapour sorption (DVS). Milling and dry mixing of SS both resulted in pXRD amorphous materials. No amorphous content of SS was detected by DVS on co-milling with 50% (w/w) GA, while amorphisation was more than halved, relative to the API milled alone, on co-milling with 50% (w/w) AA and PA, respectively. Co-mixing with each excipient also resulted in a decrease in API amorphicity, although the extent of reduction was considerably less compared to the co-milling experiments. The solubility (Solexcipient) of each excipient in amorphous SS was determined by thermal methods. No further reduction in API amorphisation was achieved on co-mixing with 50% (w/w) excipient, compared to concentrations corresponding to the solubility of each excipient in the amorphous API (SolGA=36%, SolAA=21%, SolPA=22%). PXRD confirmed gradual dissolution over time of GA in amorphous SS on co-mixing. In contrast to co-mixing, co-milling SS at excipient weight fractions above their respective solubilities in the amorphous drug resulted in further reductions in API amorphisation. This is thought to be due to the generation of a molecular dispersion of amorphous API, supersaturated with excipient, thereby leading to a more pronounced composite Tg lowering effect. The results indicate that co-processing with low Tg excipients is an effective strategy at

  20. Purification of human immunoglobulins by sequential precipitation with caprylic acid and ammonium sulphate.

    PubMed

    Perosa, F; Carbone, R; Ferrone, S; Dammacco, F

    1990-03-27

    We have tested the usefulness of sequential precipitation with caprylic acid and ammonium sulfate to purify human monoclonal and polyclonal immunoglobulins from sera of 11 patients with monoclonal gammapathy (4 IgG kappa, 2 IgG lambda, 2 IgM kappa, 1 IgA kappa, 2 IgA lambda), four patients with autoimmune diseases and four healthy donors. In terms of purity and activity of Ig as well as execution time and cost, this two-step non-chromatographic procedure is highly efficient for the purification of IgG, IgA and IgM, thus offering several advantages over other methods of purification. Therefore, this procedure may have useful application in the preparation of human Ig for structural studies and therapeutic purposes.

  1. cis-Urocanic Acid Attenuates Acute Dextran Sodium Sulphate-Induced Intestinal Inflammation

    PubMed Central

    Albert, Eric; Walker, John; Thiesen, Aducio; Churchill, Thomas; Madsen, Karen

    2010-01-01

    On exposure to sunlight, urocanic acid (UCA) in the skin is converted from trans to the cis form and distributed systemically where it confers systemic immunosuppression. The aim of this study was to determine if administration of cis-UCA would be effective in attenuating colitis and the possible role of IL-10. Colitis was induced in 129/SvEv mice by administering 5% dextran sodium sulfate (DSS) for 7 days in drinking water. During this period mice received daily subcutaneously injections of cis-UCA or vehicle. To examine a role for IL-10, 129/SvEv IL-10−/− mice were injected for 24 days with cis-UCA or vehicle. Clinical disease was assessed by measurement of body weight, stool consistency, and presence of blood. At sacrifice, colonic tissue was collected for histology and measurement of myeloperoxidase and cytokines. Splenocytes were analyzed for CD4+CD25+FoxP3+ T-regulatory cells via flow cytometry. Murine bone-marrow derived antigen-presenting cells were treated with lipopolysaccharide (LPS) ± UCA and cytokine secretion measured. Our results demonstrated that cis-UCA at a dose of 50 µg was effective in ameliorating DSS-induced colitis as evidenced by reduced weight loss and attenuated changes in colon weight/length. This protection was associated with reduced colonic expression of CXCL1, an increased expression of IL-17A and a significant preservation of splenic CD4+CD25+FoxP3+ T-regulatory cells. cis-UCA decreased LPS induced CXCL1, but not TNFα secretion, from antigen-presenting cells in vitro. UCA reduced colonic levels of IFNγ in IL-10−/− mice but did not attenuate colitis. In conclusion, this study demonstrates that cis-urocanic acid is effective in reducing the severity of colitis in a chemically-induced mouse model, indicating that pathways induced by ultraviolet radiation to the skin can influence distal sites of inflammation. This provides further evidence for a possible role for sunlight exposure in modulating inflammatory disorders. PMID

  2. Secreted Protein Acidic and Rich in Cysteine (SPARC) Exacerbates Colonic Inflammatory Symptoms in Dextran Sodium Sulphate-Induced Murine Colitis

    PubMed Central

    Ng, Yoke-Leng; Klopcic, Borut; Lloyd, Frances; Forrest, Cynthia; Greene, Wayne; Lawrance, Ian C.

    2013-01-01

    Background Secreted Protein Acidic and Rich in Cysteine (SPARC) is expressed during tissue repair and regulates cellular proliferation, migration and cytokine expression. The aim was to determine if SPARC modifies intestinal inflammation. Methods Wild-type (WT) and SPARC-null (KO) mice received 3% dextran sodium sulphate (DSS) for 7 days. Inflammation was assessed endoscopically, clinically and histologically. IL-1β, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17A, IL-12/IL23p40, TNF-α, IFN-γ, RANTES, MCP-1, MIP-1α, MIP-1β, MIG and TGF-β1 levels were measured by ELISA and cytometric bead array. Inflammatory cells were characterised by CD68, Ly6G, F4/80 and CD11b immunofluorescence staining and regulatory T cells from spleen and mesenteric lymph nodes were assessed by flow cytometry. Results KO mice had less weight loss and diarrhoea with less endoscopic and histological inflammation than WT animals. By day 35, all (n = 13) KO animals completely resolved the inflammation compared to 7 of 14 WT mice (p<0.01). Compared to WTs, KO animals at day 7 had less IL1β (p = 0.025) and MIG (p = 0.031) with higher TGFβ1 (p = 0.017) expression and a greater percentage of FoxP3+ regulatory T cells in the spleen and draining lymph nodes of KO animals (p<0.01). KO mice also had fewer CD68+ and F4/80+ macrophages, Ly6G+ neutrophils and CD11b+ cells infiltrating the inflamed colon. Conclusions Compared to WT, SPARC KO mice had less inflammation with fewer inflammatory cells and more regulatory T cells. Together, with increased TGF-β1 levels, this could aid in the more rapid resolution of inflammation and restoration of the intestinal mucosa suggesting that the presence of SPARC increases intestinal inflammation. PMID:24204877

  3. A Biphasic Calcium Sulphate/Hydroxyapatite Carrier Containing Bone Morphogenic Protein-2 and Zoledronic Acid Generates Bone

    PubMed Central

    Raina, Deepak Bushan; Isaksson, Hanna; Hettwer, Werner; Kumar, Ashok; Lidgren, Lars; Tägil, Magnus

    2016-01-01

    In orthopedic surgery, large amount of diseased or injured bone routinely needs to be replaced. Autografts are mainly used but their availability is limited. Commercially available bone substitutes allow bone ingrowth but lack the capacity to induce bone formation. Thus, off-the-shelf osteoinductive bone substitutes that can replace bone grafts are required. We tested the carrier properties of a biphasic, calcium sulphate and hydroxyapatite ceramic material, containing a combination of recombinant human bone morphogenic protein-2 (rhBMP-2) to induce bone, and zoledronic acid (ZA) to delay early resorption. In-vitro, the biphasic material released 90% of rhBMP-2 and 10% of ZA in the first week. No major changes were found in the surface structure using scanning electron microscopy (SEM) or in the mechanical properties after adding rhBMP-2 or ZA. In-vivo bone formation was studied in an abdominal muscle pouch model in rats (n = 6/group). The mineralized volume was significantly higher when the biphasic material was combined with both rhBMP-2 and ZA (21.4 ± 5.5 mm3) as compared to rhBMP-2 alone (10.9 ± 2.1 mm3) when analyzed using micro computed tomography (μ-CT) (p < 0.01). In the clinical setting, the biphasic material combined with both rhBMP-2 and ZA can potentially regenerate large volumes of bone. PMID:27189411

  4. Dehydroepiandrosterone-sulphate replacement improves the human plasma fatty acid profile in plasma of obese women.

    PubMed

    Gómez-Santos, C; Larqué, E; Granero, E; Hernández-Morante, J J; Garaulet, M

    2011-12-11

    DHEA-S treatment is used as an anti-aging and anti-obesity hormone therapy in adults; however, it mechanisms of action are not clearly elucidated. The objective of the present work was to analyze the effect of a replacement therapy, which included a daily single oral dose of DHEA-S for three months, on the composition of human plasma fatty acids (FAs) in obese women. In the first study, a randomized, double-blind, placebo-controlled trial was conducted involving 61 postmenopausal women, who were assigned to receive 100mg/day of DHEA-S (n = 41) or placebo (n = 20) orally for 3 months. In a second study, the effect of DHEA-S treatment on postmenopausal obese women (n = 41) was compared to that in premenopausal obese women (n = 20). Blood samples were collected at the beginning and at the end of the treatment. Plasma FAs were analyzed by gas chromatography. DHEA-S treatment produced significant changes in plasma FAs of both post- and premenopausal women with a reduction of total saturated FAs (SFA) as well as an increase in n-6 polyunsaturated FA (PUFA). Particularly, in premenopausal women the DHEA-S treatment also increased the plasma n-3 PUFA percentage. Regarding estimation of desaturase activity, our data showed that Δ6-desaturase was significantly decreased in postmenopausal women after DHEA-S treatment, whereas Δ5-desaturase was increased in the premenopausal group. In conclusion, DHEA-S treatment in obese women modifies plasma FA composition towards a potentially better metabolic profile, mainly by decreasing SFA and increasing n-6 PUFA in both postmenopausal and premenopausal women.

  5. [Medication use during the first trimester of pregnancy: drug safety and adoption of folic acid and ferrous sulphate].

    PubMed

    Lunardi-Maia, Tânia; Schuelter-Trevisol, Fabiana; Galato, Dayani

    2014-12-01

    To identify the profile of use of medication during the first trimester of pregnancy with emphasis on safety assessment and on the adoption of folic acid and ferrous sulfate by pregnant women attended at a Basic Health Unit in Brazil. This was a cross-sectional study nested in a cohort of pregnant women. Medications were classified according to the Anatomical Therapeutic Chemical (ATC), and their safety was evaluated according to the Food and Drug Administration (FDA) and the Brazilian Health Surveillance Agency (ANVISA). The adoption of ferrous sulfate and folic acid was investigated according to the protocol set forth by the Brazilian Ministry of Health. The survey included 212 pregnant women, 46.7% of whom were taking medications at the time of pregnancy diagnosis, and 97.6% used medication during the first trimester after diagnosis. The highest percentage of self-medication occurred before the beginning of prenatal care (64.9%). According to the FDA criteria, there was a high level of exposure to D and X risk drugs before the beginning of prenatal care (23.0%), which was also observed for drugs not recommended by ANVISA (36.5%). Of the surveyed sample, 32.5% did not follow the protocol of the Brazilian Ministry of Health. In all, 67.9% of pregnant women had inadequate drug exposure. There was a difference between the proportions of drugs used according to the ATC, and the main anatomical groups identified were the drugs that act on blood and blood-forming organs, and anti-infective medications for systemic use. When pregnancy was diagnosed, the use of a large number of medications that act on the genitourinary system and sex hormones (16.2%) was identified, such as oral contraceptives, a fact probably related to the percentage of unplanned pregnancies (67.0%), on the same occasion 4 pregnant women used folic acid and 3 used ferrous sulphate. The present results show that a large number of medications are used during pregnancy. Even if there was little exposure

  6. 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.

  7. HONO (nitrous acid) emissions from acidic northern soils

    NASA Astrophysics Data System (ADS)

    Maljanen, Marja; Yli-Pirilä, Pasi; Joutsensaari, Jorma; Sulassaari, Sirkka; Martikainen, Pertti J.

    2014-05-01

    The photolysis of HONO (nitrous acid) is an important source of OH radical, the key oxidizing agent in the atmosphere, contributing also to removal of atmospheric methane (CH4), the second most important greenhouse gas after carbon dioxide (CO2). There are missing sources of HONO when considering the chemical reactions in the atmosphere. Soil could be such a missing source. Emissions of HONO from soils studied in laboratory incubations have been recently reported. The soil-derived HONO has been connected to soil nitrite (NO2-) and a study with an ammonium oxidizing bacterium has shown that HONO could be produced in ammonium oxidation. Our hypothesis was that boreal acidic soils with high nitrification activity could be important sources of HONO. We selected a range of dominant northern acidic soils and showed in microcosm experiments that soils which have the highest nitrous oxide (N2O) and nitric oxide (NO) emissions (drained peatlands) also have the highest HONO production rates. The emissions of HONO are thus linked to nitrogen cycle processes. In contrast to drained peatlands, natural peatlands with high water table and boreal coniferous forests on mineral soils with low nitrification capacity had low HONO emissions. It is known that in natural peatlands with high water table and in boreal coniferous forest soils, low nitrification activity (microbial production of nitrite and nitrate) limits their N2O production. Low nitrification rate and low availability of nitrite in these soils are the likely reasons for their low HONO production rates. We studied the origin of HONO in one drained peat soil by inhibiting nitrification with acetylene. Acetylene blocked NO emissions but did not affect HONO or N2O emissions, thus ammonium oxidation is not the direct mechanism for the HONO emission in this soil. It is still an open question if HONO originates directly from some microbial process like ammonium oxidation or chemically from nitrite produced in microbial processes.

  8. HONO (nitrous acid) emissions from acidic northern soils

    NASA Astrophysics Data System (ADS)

    Maljanen, Marja; Yli-Pirilä, Pasi; Joutsensaari, Jorma; Martikainen, Pertti J.

    2015-04-01

    The photolysis of HONO (nitrous acid) is an important source of OH radical, the key oxidizing agent in the atmosphere, contributing also to removal of atmospheric methane (CH4), the second most important greenhouse gas after carbon dioxide (CO2). The emissions of HONO from soils have been recently reported in few studies. Soil HONO emissions are regarded as missing sources of HONO when considering the chemical reactions in the atmosphere. The soil-derived HONO has been connected to soil nitrite (NO2-) and also directly to the activity of ammonia oxidizing bacteria, which has been studied with one pure culture. Our hypothesis was that boreal acidic soils with high nitrification activity could be also sources of HONO and the emissions of HONO are connected with nitrification. We selected a range of dominant northern acidic soils and showed in microcosm experiments that soils which have the highest nitrous oxide (N2O) and nitric oxide (NO) emissions (drained peatlands) also have the highest HONO production rates. The emissions of HONO are thus linked to nitrogen cycle and also NO and N2O emissions. Natural peatlands and boreal coniferous forests on mineral soils had the lowest HONO emissions. It is known that in natural peatlands with high water table and in boreal coniferous forest soils, low nitrification activity (microbial production of nitrite and nitrate) limits their N2O production. Low availability of nitrite in these soils is the likely reason also for their low HONO production rates. We also studied the origin of HONO in one peat soil with acetylene and other nitrification inhibitors and we found that HONO production is not closely connected to ammonium oxidation (nitrification). Acetylene blocked NO emissions but did not affect HONO or N2O emissions, thus there is another source behind HONO emission from these soils than ammonium oxidation. It is still an open question if this process is microbial or chemical origin.

  9. Survival of Rhizobium in Acid Soils

    PubMed Central

    Lowendorf, Henry S.; Baya, Ana Maria; Alexander, Martin

    1981-01-01

    A Rhizobium strain nodulating cowpeas did not decline in abundance after it was added to sterile soils at pH 6.9 and 4.4, and the numbers fell slowly in nonsterile soils at pH 5.5 and 4.1. A strain of R. phaseoli grew when added to sterile soils at pH 6.7 and 6.9; it maintained large, stable populations in soils of pH 4.4, 5.5, and 6.0, but the numbers fell markedly and then reached a stable population size in sterile soils at pH 4.3 and 4.4. The abundance of R. phaseoli added to nonsterile soils with pH values of 4.3 to 6.7 decreased similarly with time regardless of soil acidity, and the final numbers were less than in the comparable sterile soils. The minimum pH values for the growth of strains of R. meliloti in liquid media ranged from 5.3 to 5.9. Two R. meliloti strains, which differed in acid tolerance for growth in culture, did not differ in numbers or decline when added to sterile soils at pH 4.8, 5.2, and 6.3. The population size of these two strains was reduced after they were introduced into nonsterile soils at pH 4.8, 5.4, and 6.4, and the number of survivors was related to the soil pH. The R. meliloti strain that was more acid sensitive in culture declined more readily in sterile soil at pH 4.6 than did the less sensitive strain, and only the former strain was eliminated from nonsterile soil at pH 4.8; however, the less sensitive strain also survived better in limed soil. The cell density of the two R. meliloti strains was increased in pH 6.4 soil in the presence of growing alfalfa. The decline and elimination of the tolerant, but not the sensitive, strain was delayed in soil at pH 4.6 by roots of growing alfalfa. PMID:16345909

  10. Analytical applications of condensed phosphoric acid-III Iodometric determination of sulphur after reduction of sulphate with sodium hypophosphite and either tin metal or potassium iodide in condensed phosphoric acid.

    PubMed

    Mizoguchi, T; Iwahori, H; Ishii, H

    1980-06-01

    Novel methods for the reduction of sulphate to hydrogen sulphide with hypophosphite-tin metal or hypophosphite-iodide in condensed phosphoric acid (CPA) are proposed. The reduction of sulphate with hypophosphite alone does not proceed quantitatively. Sulphate, however, is quantitatively decomposed with hypophosphite when tin metal or potassium iodide is used together with it. The determination of sulphur by the hypophosphite-tin metal-CPA and tin(II)-CPA methods is interfered with by copper on account of the stabilization of copper(I) sulphide, but this interference can be eliminated by adding iodide, e.g. potassium and lead salts. Alum and barytes are quantitatively decomposed within 15 min at 140 and 280 degrees , respectively. The hydrogen sulphide evolved is absorbed in zinc acetate solution at pH 4.5 and then determined by iodometry.

  11. Sulphate absorption across biological membranes.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2016-01-01

    1. Sulphonation is unusual amongst the common Phase II (condensation; synthetic) reactions experienced by xenobiotics, in that the availability of the conjugating agent, sulphate, may become a rate-limiting factor. This sulphate is derived within the body via the oxygenation of sulphur moieties liberated from numerous ingested compounds including the sulphur-containing amino acids. Preformed inorganic sulphate also makes a considerable contribution to this pool. 2. There has been a divergence of opinion as to whether or not inorganic sulphate may be readily absorbed from the gastrointestinal tract and this controversy still continues in some quarters. Even more so, is the vexing question of potential absorption of inorganic sulphate via the lungs and through the skin. 3. This review examines the relevant diverse literature and concludes that sulphate ions may move across biological membranes by means of specific transporters and, although the gastrointestinal tract is by far the major portal of entry, some absorption across the lungs and the skin may take place under appropriate circumstances.

  12. Soil acid cations induced reduction in soil respiration under nitrogen enrichment and soil acidification.

    PubMed

    Li, Yong; Sun, Jian; Tian, Dashuan; Wang, Jinsong; Ha, Denglong; Qu, Yuxi; Jing, Guangwei; Niu, Shuli

    2017-09-16

    Atmospheric nitrogen (N) deposition and soil acidification both can largely change soil microbial activity and root growth with a consequent impact on soil respiration (Rs). However, it remains unclear which one, N enrichment or soil acidification, plays more important role in impacting soil respiration. We conducted a manipulative experiment to simulate N enrichment (10gm(-2)yr(-1) NH4NO3) and soil acidity (0.552molH(+)m(-2)yr(-1) sulfuric acid) and compared their effects on Rs and its components in a subtropical forest. The results showed that soil pH was reduced by 0.4 similarly under N addition or acid addition after 3years' treatment. Acid addition decreased autotrophic respiration (Ra) by 22-35% and heterotrophic respiration (Rh) by 22-23%, resulting in a reduction of Rs by 22-26% in the two years. N addition reduced Ra, Rh, Rs less than acid addition did. The reductions of Rs and its components were attributed to increase of soil acid cations and reduction of cellulose degrading enzymes activity. N addition and soil acidification significantly enhanced fungal to bacterial ratio. All the cellulose degrading enzymes were reduced more by soil acidity (43-50%) than N addition (30-39%). The principal component scores of degrading enzymes activity showed significantly positive relationships with Rh. Structural equation model showed that soil acidification played more important role than N enrichment in changing Rs and its components. We therefore suggest that soil acidification is an important mechanism underlying soil respiration changes, and should be incorporated into biogeochemical models to improve the prediction of ecosystem C cycling in the future scenarios of anthropogenic N deposition and acid enrichment. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Calcium sulphate in ammonium sulphate solution

    USGS Publications Warehouse

    Sullivan, E.C.

    1905-01-01

    Calcium sulphate, at 25?? C., is two-thirds as soluble in dilute (o.i mol per liter) and twice as soluble in concentrated (3 mois per liter) ammonium sulphate solution as in water. The specific electric conductivity of concentrated ammonium sulphate solutions is lessened by saturating with calcium sulphate. Assuming that dissociation of ammonium sulphate takes place into 2NH4?? and SO4" and of calcium sulphate into Ca and SO4" only, and that the conductivity is a measure of such dissociation, the solubility of calcium sulphate in dilute ammonium sulphate solutions is greater than required by the mass-law. The conductivity of the dilute mixtures may be accurately calculated by means of Arrhenius' principle of isohydric solutions. In the data obtained in these calculations, the concentration of non-dissociated calcium sulphate decreases with increasing ammonium sulphate. The work as a whole is additional evidence of the fact that we are not yet in possession of all the factors necessary for reconciling the mass-law to the behavior of electrolytes. The measurements above described were made in the chemical laboratory of the University of Michigan.

  14. Soil amino acid composition across a boreal forest successional sequence

    Treesearch

    Nancy R. Werdin-Pfisterer; Knut Kielland; Richard D. Boone

    2009-01-01

    Soil amino acids are important sources of organic nitrogen for plant nutrition, yet few studies have examined which amino acids are most prevalent in the soil. In this study, we examined the composition, concentration, and seasonal patterns of soil amino acids across a primary successional sequence encompassing a natural gradient of plant productivity and soil...

  15. Designer, acidic biochar influences calcareous soil characteristics.

    PubMed

    Ippolito, J A; Ducey, T F; Cantrell, K B; Novak, J M; Lentz, R D

    2016-01-01

    In a proof-of-concept study, an acidic (pH 5.8) biochar was created using a low pyrolysis temperature (350 °C) and steam activation (800 °C) to potentially improve the soil physicochemical status of an eroded calcareous soil. Biochar was added at 0%, 1%, 2%, and 10% (by wt.) and soils were destructively sampled at 1, 2, 3, 4, 5, and 6 month intervals. Soil was analyzed for gravimetric water content, pH, NO3-N, plant-available Fe, Zn, Mn, Cu, and P, organic C, CO2 respiration, and microbial enumeration via extractable DNA and 16S rRNA gene copies. Gravimetric soil water content increased with biochar application regardless of rate, as compared to the control. Soil pH decreased between 0.2 and 0.4 units, while plant-available Zn, Mn, and P increased with increasing biochar application rate. Micronutrient availability decreased over time likely due to insoluble mineral species precipitation. Increasing biochar application raised the soil organic C content and remained elevated over time. Increasing biochar application rate also increased respired CO2, yet the CO2 released decreased over time. Soil NO3-N concentrations significantly decreased with increasing biochar application rate likely due to microbial immobilization or denitrification. Depending on application rate, biochar produced a 1.4 to 2.1-fold increase in soil DNA extracted and 1.4- to 2.4-fold increase in 16S rRNA gene abundance over control soils, suggesting microbial stimulation and a subsequent burst of activity upon biochar addition. Our results showed that there is promise in designing a biochar to improve the quality and water relations of eroded calcareous soils.

  16. Stress Corrosion Cracking Behavior of X80 Pipeline Steel in Acid Soil Environment with SRB

    NASA Astrophysics Data System (ADS)

    Wang, Dan; Xie, Fei; Wu, Ming; Liu, Guangxin; Zong, Yue; Li, Xue

    2017-06-01

    Self-designed experimental device was adopted to ensure the normal growth of sulphate-reducing bacteria (SRB) in sterile simulated Yingtan soil solution. Stress corrosion cracking (SCC) behavior of X80 pipeline steel in simulated acid soil environment was investigated by electrochemical impedance spectroscopy, slow strain rate test, and scanning electron microscope. Results show that the presence of SRB could promote stress corrosion cracking susceptibility. In a growth cycle, polarization resistance first presents a decrease and subsequently an increase, which is inversely proportional to the quantities of SRB. At 8 days of growth, SRB reach their largest quantity of 1.42 × 103 cells/g. The corrosion behavior is most serious at this time point, and the SCC mechanism is hydrogen embrittlement. In other SRB growth stages, the SCC mechanism of X80 steel is anodic dissolution. With the increasing SRB quantities, X80 steel is largely prone to SCC behavior, and the effect of hydrogen is considerably obvious.

  17. Chloroacetic acids in European soils and vegetation.

    PubMed

    Peters, Ruud J B

    2003-04-01

    Trichloroacetic acid (TCA) and dichloroacetic acid (DCA) are possible minor atmospheric degradation products of perchloroethylene and trichloroethylene, respectively. These acids may be wet- or dry-deposited from the atmosphere to land surfaces and hence possibly affect plant growth. However, the existing database on TCA levels in soil is limited to a few studies carried out in the late 1980's and the early to mid-1990's and it was concluded that there is a need for further measurements of concentrations of TCA and DCA in soils. In this study soil samples from 10 locations in 5 European countries, as well as vegetation samples, and a limited number of rainwater and air samples were collected and analysed for DCA and TCA to determine the concentrations of these compounds. An isotope dilution method using GC-MS was used for the determination of these acids in the samples. The method was briefly validated and the performance characteristics are presented. The results of the analysis of the soil samples show that the DCA and TCA concentrations in soil from different sites in Europe are more or less comparable, with the exception of Germany, especially Freudenstadt, where significantly higher TCA concentrations (up to 12 microg kg(-1) dw) were found. The average DCA and TCA concentrations in soil in this study were 0.25 +/- 0.12 and 0.64 +/- 1.40 microg kg(-1) dw, respectively. Generally, the concentration in soils from forest areas are about twice those from open-land areas. The DCA and TCA concentrations in vegetation samples ranged from 2.1 to 73 microg kg(-1) dw for DCA and from 4.7 to 17 microg kg(-1) dw for TCA. Thus, the concentrations in vegetation samples are 10-20 times higher than the soil concentrations. DCA and TCA concentrations in wet deposition samples and air samples collected in The Netherlands were 0.14 and 0.15 microg l(-1) for wet deposition samples and <0.5 and 0.7 ng m(-3) for air samples respectively. For these samples taken in The Netherlands

  18. Effect of L-aspartic acid on the growth, structure and spectral studies of Zinc (tris) Thiourea Sulphate (ZTS) single crystals

    NASA Astrophysics Data System (ADS)

    Samuel, Bincy Susan; Krishnamurthy, R.; Rajasekaran, R.

    2014-11-01

    Single crystals of pure and L-aspartic acid doped Zinc (Tris) Thiourea Sulphate (ZTS) were grown from aqueous solution by solution growth method. The cell parameters and structure of the grown crystals were determined by X-ray diffraction studies. The presence of functional group in the compound has been confirmed by FTIR and FT-Raman analysis. The optical transparency range has been studied through UV-Vis spectroscopy. TGA/DTA studies show thermal stability of the grown crystals. Microhardness study reveals that the hardness number (Hv) increases with load for pure and doped ZTS crystals. Dielectric studies have been carried out and the results are discussed. The second harmonic generation was confirmed for L-aspartic acid doped ZTS which is greater than pure ZTS.

  19. Effect of L-aspartic acid on the growth, structure and spectral studies of Zinc (tris) Thiourea Sulphate (ZTS) single crystals.

    PubMed

    Samuel, Bincy Susan; Krishnamurthy, R; Rajasekaran, R

    2014-11-11

    Single crystals of pure and L-aspartic acid doped Zinc (Tris) Thiourea Sulphate (ZTS) were grown from aqueous solution by solution growth method. The cell parameters and structure of the grown crystals were determined by X-ray diffraction studies. The presence of functional group in the compound has been confirmed by FTIR and FT-Raman analysis. The optical transparency range has been studied through UV-Vis spectroscopy. TGA/DTA studies show thermal stability of the grown crystals. Microhardness study reveals that the hardness number (Hv) increases with load for pure and doped ZTS crystals. Dielectric studies have been carried out and the results are discussed. The second harmonic generation was confirmed for l-aspartic acid doped ZTS which is greater than pure ZTS.

  20. Cadmium, lead and zinc leaching from smelter fly ash in simple organic acids--simulators of rhizospheric soil solutions.

    PubMed

    Ettler, Vojtech; Vrtisková, Růzena; Mihaljevic, Martin; Sebek, Ondrej; Grygar, Tomás; Drahota, Petr

    2009-10-30

    Emissions from base-metal smelters are responsible for high contamination of the surrounding soils. Fly ash from a secondary Pb smelter was submitted to a batch leaching procedure (0.5-168 h) in 500 microM solutions of acetic, citric, or oxalic acids to simulate the release of toxic metals (Cd, Pb, Zn) in rhizosphere-like environments. Organic acids increased dissolution of fly ash by a factor of 1.3. Cadmium and Pb formed mobile chloro- and sulphate-complexes, whereas Zn partly present in a citrate (Zn-citrate(-)) complex is expected to be less mobile due to sorption onto the positively charged surfaces of hydrous ferric oxides (HFO) and organic matter (OM) in acidic soil.

  1. Bromine accumulation in acidic black colluvial soils

    NASA Astrophysics Data System (ADS)

    Cortizas, Antonio Martínez; Vázquez, Cruz Ferro; Kaal, Joeri; Biester, Harald; Casais, Manuela Costa; Rodríguez, Teresa Taboada; Lado, Luis Rodríguez

    2016-02-01

    Recent investigations showed that bromine is incorporated to soil organic matter (SOM), its content increasing with humification. But few research was done on its long-term accumulation and the role played by pedogenetic processes, as those involved in organic matter stabilization. We investigated bromine content and distribution in four deep, acidic, organic-rich, Holocene soils from an oceanic area of Western Europe. Bromine concentrations (93-778 μg g-1) in the silt + clay (<50 μm) fraction were on average 3-times higher than those (17-250 μg g-1) in the fine earth (<2 mm), the former containing almost all bromine (90 ± 5%). Inventories were between 148 and 314 g m-2, indicating a rather large variability in a small area, and total estimated retention was low (6-16%). The degree of SOM bromination, expressed as the Br/C molar ratio, varied between 0.03 and 1.20 mmol Br/mol C. The ratio was highly correlated (n = 23, r2 0.88, p < 0.01) with the age of the SOM for the last ∼12 ka. Partial least squares modeling indicates that bromine concentration depends on the amount of organic matter stabilized as aluminium-OM associations, and to a lesser extent on soil acidity (pH) and iron-OM associations. Thus, at scales of thousands of years, bromine accumulation in acidic soils is linked to the pool of metal-clay-stabilized organic matter.

  2. Growth and spectral characterization of ethylene diamine tetra acetic acid (EDTA) doped zinc sulphate hepta hydrate - a semi organic NLO material.

    PubMed

    Ramachandra Raja, C; Ramamurthi, K; Manimekalai, R

    2012-12-01

    Semi-organic non-linear optical single crystals of ethylene diamine tetra acetic acid (EDTA) doped zinc sulphate hepta hydrate crystals were grown by slow evaporation solution growth technique, at room temperature, using de-ionized water as solvent. The modes of vibrations of different molecular groups present in the grown crystal were identified by FT-IR technique. The optical absorbance/transmittance was recorded in the wavelength range of 190-1100 nm. Thermal properties of the grown crystal were studied by thermo gravimetric analysis and differential thermal analysis. The melting point of the grown crystal was estimated by differential scanning calorimetric analysis. The inclusion of the dopant (EDTA) was confirmed by colorimetric estimation method. The second harmonic generation efficiency is about 30% of potassium dihydrogen orthophosphate. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Vibrational spectroscopic study of sulphated silk proteins

    NASA Astrophysics Data System (ADS)

    Monti, P.; Freddi, G.; Arosio, C.; Tsukada, M.; Arai, T.; Taddei, P.

    2007-05-01

    Degummed Bombyx mori ( B. m.) silk fibroin fabric and mutant naked pupa cocoons (Nd-s) consisting of almost pure silk sericin were treated with chlorosulphonic acid in pyridine and investigated by FT-IR and FT-Raman spectroscopies. Untreated silk fibroin and sericin displayed typical spectral features due to characteristic amino acid composition and molecular conformation (prevailing β-sheet with a less ordered structure in sericin). Upon sulphation, the degree of molecular disorder increased in both proteins and new bands appeared. The IR bands at 1049 and 1014 cm -1 were attributed to vibrations of sulphate salts and that at 1385 cm -1 to the νasSO 2 mode of organic covalent sulphates. In the 1300-1180 cm -1 range various contributions of alkyl and aryl sulphate salts, sulphonamides, sulphoamines and organic covalent sulphates, fell. Fibroin covalently bound sulphate groups through the hydroxyl groups of tyrosine and serine, while sericin through the hydroxyl groups of serine, since the δOH vibrations at 1399 cm -1 in IR and at 1408 cm -1 in Raman disappeared almost completely. Finally, the increase of the I850/ I830 intensity ratio of Raman tyrosine doublet in fibroin suggested a change towards a more exposed state of tyrosine residues, in good agreement with the more disordered conformation taken upon sulphation.

  4. Differential Soil Acidity Tolerance of Tropical Legume Cover Crops

    USDA-ARS?s Scientific Manuscript database

    In tropical regions, soil acidity and low soil fertility are the most important yield limiting factors for sustainable crop production. Using legume cover crops as mulch is an important strategy not only to protect the soil loss from erosion but also ameliorating soil fertility. Information is limit...

  5. Natural abiotic formation of oxalic acid in soils: results from aromatic model compounds and soil samples.

    PubMed

    Studenroth, Sabine; Huber, Stefan G; Kotte, Karsten; Schöler, Heinz F

    2013-02-05

    Oxalic acid is the smallest dicarboxylic acid and plays an important role in soil processes (e.g., mineral weathering and metal detoxification in plants). We have first proven its abiotic formation in soils and investigated natural abiotic degradation processes based on the oxidation of soil organic matter, enhanced by Fe(3+) and H(2)O(2) as hydroxyl radical suppliers. Experiments with the model compound catechol and further hydroxylated benzenes were performed to examine a common degradation pathway and to presume a general formation mechanism of oxalic acid. Two soil samples were tested for the release of oxalic acid and the potential effects of various soil parameters on oxalic acid formation. Additionally, the soil samples were treated with different soil sterilization methods to prove the oxalic acid formation under abiotic soil conditions. Different series of model experiments were conducted to determine a range of factors including Fe(3+), H(2)O(2), reaction time, pH, and chloride concentration on oxalic acid formation. Under certain conditions, catechol is degraded up to 65.6% to oxalic acid referring to carbon. In serial experiments with two soil samples, oxalic acid was produced, and the obtained results are suggestive of an abiotic degradation process. In conclusion, Fenton-like conditions with low Fe(3+) concentrations and an excess of H(2)O(2) as well as acidic conditions were required for an optimal oxalic acid formation. The presence of chloride reduced oxalic acid formation.

  6. [Effects of low molecular weight organic acids on speciation of exogenous Cu in an acid soil].

    PubMed

    Huang, Guo-Yong; Fu, Qing-Ling; Zhu, Jun; Wan, Tian-Ying; Hu, Hong-Qing

    2014-08-01

    In order to ascertain the effect of LMWOA (citric acid, tartaric acid, oxalic acid) on Cu-contaminated soils and to investigate the change of Cu species, a red soil derived from quartz sandstone deposit was added by Cu (copper) in the form of CuSO4 x 5H2O so as to simulate soil Cu pollution, keeping the additional Cu concentrations were 0, 100, 200, 400 mg x kg(-1) respectively. After 9 months, different LMWOA was also added into the simulated soil, keeping the additional LMWOAs in soil were 0, 5, 10, 20 mmol x kg(-1) respectively. After 2 weeks incubation, the modified sequential extraction method on BCR (European Communities Bureau of Reference) was used to evaluate the effects of these LMWOAs on the changes of copper forms in soil. The result showed that the percentage of weak acid dissolved Cu, the most effective form in the soil increased with three organic acids increase in quantity in the simulated polluted soil. And there was a good activation effect on Cu in the soil when organic acid added. Activation effects on Cu increased with concentration of citric acid increasing, but it showed a rise trend before they are basically remained unchanged in the case of tartaric acid and oxalic acid added in the soil. On the contrary, the state of the reduction of copper which was regarded as a complement for effective state decreased with the increased concentration of organic acid in the soil, especially with citric acid. When 20 mmol x kg(-1) oxalic acid and citric acid were added into the soil, the activation effect was the best; whereas for tartaric, the concentration was 10 mmol x kg(-1). In general, the effect on the changes of Cu forms in the soil is citric acid > tartaric acid > oxalic acid.

  7. Reduced carbon sequestration potential of biochar in acidic soil.

    PubMed

    Sheng, Yaqi; Zhan, Yu; Zhu, Lizhong

    2016-12-01

    Biochar application in soil has been proposed as a promising method for carbon sequestration. While factors affecting its carbon sequestration potential have been widely investigated, the number of studies on the effect of soil pH is limited. To investigate the carbon sequestration potential of biochar across a series of soil pH levels, the total carbon emission, CO2 release from inorganic carbon, and phospholipid fatty acids (PLFAs) of six soils with various pH levels were compared after the addition of straw biochar produced at different pyrolysis temperatures. The results show that the acidic soils released more CO2 (1.5-3.5 times higher than the control) after the application of biochar compared with neutral and alkaline soils. The degradation of both native soil organic carbon (SOC) and biochar were accelerated. More inorganic CO2 release in acidic soil contributed to the increased degradation of biochar. Higher proportion of gram-positive bacteria in acidic soil (25%-36%) was responsible for the enhanced biochar degradation and simultaneously co-metabolism of SOC. In addition, lower substrate limitation for bacteria, indicated by higher C-O stretching after the biochar application in the acidic soil, also caused more CO2 release. In addition to the soil pH, other factors such as clay contents and experimental duration also affected the phsico-chemical and biotic processes of SOC dynamics. Gram-negative/gram-positive bacteria ratio was found to be negatively related to priming effects, and suggested to serve as an indicator for priming effect. In general, the carbon sequestration potential of rice-straw biochar in soil reduced along with the decrease of soil pH especially in a short-term. Given wide spread of acidic soils in China, carbon sequestration potential of biochar may be overestimated without taking into account the impact of soil pH. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Inactivation of Heat Adapted and Chlorine Adapted Listeria Monocytogenes ATCC 7644 on Tomatoes Using Sodium Dodecyl Sulphate, Levulinic Acid and Sodium Hypochlorite Solution.

    PubMed

    Ijabadeniyi, Oluwatosin Ademola; Mnyandu, Elizabeth

    2017-04-13

    The effectiveness of sodium dodecyl sulphate (SDS), sodium hypochlorite solution and levulinic acid in reducing the survival of heat adapted and chlorine adapted Listeria monocytogenes ATCC 7644 was evaluated. The results against heat adapted L. monocytognes revealed that sodium hypochlorite solution was the least effective, achieving log reduction of 2.75, 2.94 and 3.97 log colony forming unit (CFU)/mL for 1, 3 and 5 minutes, respectively. SDS was able to achieve 8 log reduction for both heat adapted and chlorine adapted bacteria. When used against chlorine adapted L. monocytogenes sodium hypochlorite solution achieved log reduction of 2.76, 2.93 and 3.65 log CFU/mL for 1, 3 and 5 minutes, respectively. Using levulinic acid on heat adapted bacteria achieved log reduction of 3.07, 2.78 and 4.97 log CFU/mL for 1, 3, 5 minutes, respectively. On chlorine adapted bacteria levulinic acid achieved log reduction of 2.77, 3.07 and 5.21 log CFU/mL for 1, 3 and 5 minutes, respectively. Using a mixture of 0.05% SDS and 0.5% levulinic acid on heat adapted bacteria achieved log reduction of 3.13, 3.32 and 4.79 log CFU/mL for 1, 3 and 5 minutes while on chlorine adapted bacteria it achieved 3.20, 3.33 and 5.66 log CFU/mL, respectively. Increasing contact time also increased log reduction for both test pathogens. A storage period of up to 72 hours resulted in progressive log reduction for both test pathogens. Results also revealed that there was a significant difference (P≤0.05) among contact times, storage times and sanitizers. Findings from this study can be used to select suitable sanitizers and contact times for heat and chlorine adapted L. monocytogenes in the fresh produce industry.

  9. Differential soil acidity tolerance of dry bean genotypes

    USDA-ARS?s Scientific Manuscript database

    Soil acidity is a major yield limiting factors for bean production in the tropical regions. Using soil acidity tolerant genotypes is an important strategy in improving bean yields and reducing cost of production. A greenhouse experiment was conducted with the objective of evaluating 20 dry bean geno...

  10. Acidity field of soils as ion-exchange systems and the diagnostics of genetic soil horizons

    NASA Astrophysics Data System (ADS)

    Kokotov, Yu. A.; Sukhacheva, E. Yu.; Aparin, B. F.

    2014-12-01

    For the comprehensive description of the acidity of a two-phase ion-exchange system, we should analyze two curves of the ionite titration by a strong base in water and salt solutions and find the quantitative relationships between the corresponding pH characteristics. An idea of the three-dimensional field of acidity of ion-exchange systems (the phase space of the soil acidity characteristics) and its three two-dimensional projections is suggested. For soils, three interrelated characteristics—the pH values of the salt and water extracts and the degree of base saturation—can serve as spatial coordinates for the acidity field. Representation of factual data in this field makes it possible to compare and analyze the acidity characteristics of different soils and soil horizons and to determine their specific features. Differentiation of the field into separate volumes allows one to present the data in a discrete form. We have studied the distribution patterns of the groups of soil horizons from Leningrad oblast and other regions of northwestern Russia in the acidity field. The studied samples are grouped in different partially overlapping areas of the projections of the acidity field. The results of this grouping attest to the correctness of the modern classification of Russian soils. A notion of the characteristic soil area in the acidity field is suggested; it can be applied to all the soils with a leaching soil water regime.

  11. Rosmarinic acid suppresses colonic inflammation in dextran sulphate sodium (DSS)-induced mice via dual inhibition of NF-κB and STAT3 activation

    PubMed Central

    Jin, Bo-Ram; Chung, Kyung-Sook; Cheon, Se-Yun; Lee, Minho; Hwang, Soonjae; Noh Hwang, Sam; Rhee, Ki-Jong; An, Hyo-Jin

    2017-01-01

    Ulcerative colitis (UC), a type of inflammatory bowel disease (IBD), is a chronic inflammatory disorder of the colon. Although UC is generally treated with anti-inflammatory drugs or immunosuppressants, most of these treatments often prove to be inadequate. Rosmarinic acid (RA) is a phenolic ester included in various medicinal herbs such as Salvia miltiorrhiz and Perilla frutescens. Although RA has many biological and pharmacological activities, the anti-inflammatory effect of RA in colonic tissue remains unclear. In this study, we investigated the anti-inflammatory effects and underlying molecular mechanism of RA in mice with dextran sulphate sodium (DSS)-induced colitis. In the DSS-induced colitis model, RA significantly reduced the severity of colitis, as assessed by disease activity index (DAI) scores, colonic damage, and colon length. In addition, RA resulted in the reduction of the inflammatory-related cytokines, such as IL-6, IL-1β, and IL-22, and protein levels of COX-2 and iNOS in mice with DSS-induced colitis. Furthermore, RA effectively and pleiotropically inhibited nuclear factor-kappa B and signal transducer and activator of transcription 3 activation, and subsequently reduced the activity of pro-survival genes that depend on these transcription factors. These results demonstrate that RA has an ameliorative effect on colonic inflammation and thus a potential therapeutic role in colitis. PMID:28383063

  12. Morphological changes of bladder mucosa in patients who underwent instillation with combined sodium hyaluronic acid-chondroitin sulphate (Ialuril®).

    PubMed

    Costantini, E; Lazzeri, M; Pistolesi, D; Del Zingaro, M; Frumenzio, E; Boni, A; Pietropaolo, A; Fragalà, E; Porena, M

    2013-01-01

    To investigate what changes are endoscopically evident after glycosaminoglycans (GAGs) therapy by hyaluronic acid (HA) and chondroitin sulphate (CS) (Ialuril®) in female patients affected by bladder pain syndrome(BPS)/ interstitial cystitis (IC) or recurrent urinary tract infections (rUTIs). 21 female patients over 18 years affected by rUTIs or BPS/IC received intravesical instillation of HA and CS (4 weekly instillations followed by 2 instillations every 2 weeks and 2 instillation monthly). Post-treatment evaluation included cystoscopy and patient assessment of improvement in symptoms and satisfaction on a visual analogue scale (VAS) from 0 to 10. The post-treatment endoscopy showed a positive effect on bladder mucosa morphology. In 2 cases, treatment did not change endoscopic findings and clinical symptoms. In the other patients, when macroscopic features of the bladder mucosa normalized, the clinical picture improved. GAGs therapy by HA and CS (Ialuril) improves the morphology of bladder mucosa in patients with rUTI or BPS/IC. Copyright © 2013 S. Karger AG, Basel.

  13. Improved analyses for soil carbohydrates, amino acids, and phenols: Tools for understanding soil processes

    USDA-ARS?s Scientific Manuscript database

    A process-level understanding of soil carbon(C) and nitrogen (N) cycling will be facilitated by precise measurement of biochemical compounds in soil organic matter. This review summarizes some recent developments in analyses for soil carbohydrates, amino compounds (amino acids and amino sugars), and...

  14. Randomised clinical trial: mucosal protection combined with acid suppression in the treatment of non-erosive reflux disease - efficacy of Esoxx, a hyaluronic acid-chondroitin sulphate based bioadhesive formulation.

    PubMed

    Savarino, V; Pace, F; Scarpignato, C

    2017-03-01

    Several studies have shown that patients with non-erosive reflux disease (NERD) are less responsive to proton pump inhibitors (PPIs) than those with erosive disease as they belong to different subgroups, in whom factors other than acid can trigger symptoms. To evaluate whether combined therapy (mucosal protection plus acid suppression) would improve symptom relief compared to PPI treatment alone. In a multicenter, randomised, double-blind trial, 154 patients with NERD were randomised to receive Esoxx (Alfa Wassermann, Bologna, Italy), a hyaluronic acid-chondroitin sulphate based bioadhesive formulation, or placebo, in addition to acid suppression with standard dose PPIs for 2 weeks. Symptoms (heartburn, acid regurgitation, retrosternal pain and acid taste in the mouth) and health-related quality of life (HRQL) were evaluated before and after treatment. The primary endpoint was the proportion of patients with at least a 3-point reduction in the total symptom score. At the end of treatment, the primary endpoint was reached by 52.6% of patients taking Esoxx compared to 32.1% of those given placebo (P < 0.01). The same was true also for HRQL, evaluated by means of the Short Form-36 questionnaire, which improved with both treatments, but some items were significantly better after Esoxx plus PPI therapy. The synergistic effect of Essox with PPI treatment suggests that mucosal protection added to acid suppression could improve symptoms and HRQL in NERD patients. © 2017 The Authors. Alimentary Pharmacology and Therapeutics published by John Wiley & Sons Ltd.

  15. Effects of mouthrinses with triclosan, zinc ions, copolymer, and sodium lauryl sulphate combined with fluoride on acid formation by dental plaque in vivo.

    PubMed

    Giertsen, Elin

    2004-01-01

    Bacteriological tests demonstrated a slight synergistic effect of triclosan and sodium lauryl sulphate (SLS) on the growth of Streptococcus mutans NCTC 10449 and Streptococcus sanguis ATCC 10556 in vitro. A single mouthrinse with SLS (17.4 mM) or SLS plus triclosan (3.5 mM) significantly decreased the number of salivary mutans streptococci in a group of 12 subjects up to 90 min after rinsing. The effect on plaque pH of a mouthrinse with either 12.0 mM NaF, NaF plus 10.0 mM zinc acetate, NaF plus 17.4 mM SLS, or NaF plus SLS plus 3.5 mM triclosan with or without the addition of zinc ions or 0.65% w/v of a polyvinylmethyl ether/maleic acid copolymer was investigated. The plaque pH responses to a 10% w/v sucrose mouthrinse were measured in 2-day-old plaque with microtouch pH electrodes in six groups of 10 subjects 90 min after a single mouthrinse with test solution. There was no significant difference in plaque pH between the various mouthrinses. In conclusion, triclosan enhanced the growth-inhibitory activity of SLS against oral streptococci in vitro but not against salivary mutans streptococci in vivo. Neither triclosan incorporated into a mouthrinse containing SLS plus fluoride, nor the addition of zinc ions or copolymer affected acid formation by dental plaque in vivo.

  16. Administration of cholecystokinin sulphated octapeptide (CCK-8S) induces changes on rat amino acid tissue levels and on a behavioral test for anxiety.

    PubMed

    Acosta, G B

    1998-10-01

    1. The effect of the intraperitoneal administration of cholecystokinin sulphated octapeptide (CCK-8S) (10 nmol/kg i.p.) on endogenous levels of several amino acids in five areas of the rat brain was analyzed. The olfactory bulb, hypothalamus, hippocampus, cerebral frontal cortex, and corpus striatum were evaluated. In addition, the effects of CCK-8S and PD 135,158 (1 mg/kg), a selective CCK(B) antagonist, on the performance of rats submitted to a dark/light transition test were also studied. 2. Upon administration of CCK-8S, the concentration of glutamate was reduced (27%) in the olfactory bulb. The same was observed when the levels of glycine (31%) or alanine (43%) were determined. No significant effects were produced by CCK-8S on cortical and hypothalamic levels. In the hippocampus, the concentration of both glutamate (27%) and taurine (29%) were reduced, whereas the levels of GABA in the striatum (29%) were increased. 3. After a single injection of CCK-8S, the time spent by the rats in the illuminated site of the dark/light transition test box, was not changed. On the contrary, the administration of PD 135,158 increased the time spent in the lighted compartment. 4. These results show that systemic administration of CCK-8S produced regional specific changes in brain amino acids, without producing any significant behavioral modification in the rat exposed to a dark/light box. In contrast, the selective CCKB receptor antagonist, PD 135,158, induces anxiolytic-like action in an animal model of anxiety.

  17. 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...

  18. Spore-forming, Desulfosporosinus-like sulphate-reducing bacteria from a shallow aquifer contaminated with gasoline.

    PubMed

    Robertson, W J; Franzmann, P D; Mee, B J

    2000-02-01

    Previous studies on the geochemistry of a shallow unconfined aquifer contaminated with hydrocarbons suggested that the degradation of some hydrocarbons was linked to bacterial sulphate reduction. There was attenuation of naphthalene, 1,3,5-trimethylbenzene (TMB), toluene, p-xylene and ethylbenzene in the groundwater with concomitant loss of sulphate. Here, the recovery of eight strains of sulphate-reducing bacteria (SRB) from the contaminated site is reported. All were straight or curved rod-shaped cells which formed endospores. Amplification and sequencing of the 16S rDNA indicated that the strains were all sulphate reducers of the Gram-positive line of descent, and were most closely related to Desulfosporosinus (previously Desulfotomaculum) orientis DSM 8344 (97-98.9% sequence similarity). The strains clustered in three phylogenetic groups based on 16S rRNA sequences. Whole cell fatty acid compositions were similar to those of D. orientis DSM 8344, and were consistent with previous studies of fatty acids in soil and groundwater from the site. Microcosms containing groundwater from this aquifer indicated a role for sulphate reduction in the degradation of [ring-UL-14C]toluene, but not for the degradation of [UL-14C]benzene which could also be degraded by the microcosms. Adding one of the strains that was isolated from the groundwater (strain T2) to sulphate-enriched microcosms increased the rate of toluene degradation four- to 10-fold but had no effect on the rate of benzene degradation. The addition of molybdate, an inhibitor of sulphate reduction, to the groundwater samples decreased the rate of toluene mineralization. There was no evidence to support the mineralization of [UL-14C]benzene, [ring-UL-14C]toluene or unlabelled m-xylene, p-xylene, ethylbenzene, TMB or naphthalene by any of the strains in pure culture. Growth of all the strains was completely inhibited by 100 micromol l-1 TMB.

  19. Modeling the influence of organic acids on soil weathering

    NASA Astrophysics Data System (ADS)

    Lawrence, Corey; Harden, Jennifer; Maher, Kate

    2014-08-01

    Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

  20. Modeling the influence of organic acids on soil weathering

    USGS Publications Warehouse

    Lawrence, Corey R.; Harden, Jennifer W.; Maher, Kate

    2014-01-01

    Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

  1. Vegetation types on acid soils of Micronesia

    Treesearch

    Marjorie C. Falanruw; Thomas G.. Cole; Craig D. Whitesell

    1987-01-01

    The soils and vegetation of the Caroline high islands, Federated States of Micronesia, are being mapped by the U.S. Department of Agriculture's Forest Service and Soil Conservation Service. By the end of 1987, vegetation maps and reports on Kosrae, Pohnpei, Yap, four Truk Islands, and Palau are expected to be available. To compare soil types with vegetation types...

  2. Chemical evaluation of soil-solution in acid forest soils

    USGS Publications Warehouse

    Lawrence, G.B.; David, M.B.

    1996-01-01

    Soil-solution chemistry is commonly studied in forests through the use of soil lysimeters.This approach is impractical for regional survey studies, however, because lysimeter installation and operation is expensive and time consuming. To address these problems, a new technique was developed to compare soil-solution chemistry among red spruce stands in New York, Vermont, New Hampshire, Maine. Soil solutions were expelled by positive air pressure from soil that had been placed in a sealed cylinder. Before the air pressure was applied, a solution chemically similar to throughfall was added to the soil to bring it to approximate field capacity. After the solution sample was expelled, the soil was removed from the cylinder and chemically analyzed. The method was tested with homogenized Oa and Bs horizon soils collected from a red spruce stand in the Adirondack Mountains of New York, a red spruce stand in east-central Vermont, and a mixed hardwood stand in the Catskill Mountains of New York. Reproducibility, effects of varying the reaction time between adding throughfall and expelling soil solution (5-65 minutes) and effects of varying the chemical composition of added throughfall, were evaluated. In general, results showed that (i) the method was reproducible (coefficients of variation were generally < 15%), (ii) variations in the length of reaction-time did not affect expelled solution concentrations, and (iii) adding and expelling solution did not cause detectable changes in soil exchange chemistry. Concentrations of expelled solutions varied with the concentrations of added throughfall; the lower the CEC, the more sensitive expelled solution concentrations were to the chemical concentrations of added throughfall. Addition of a tracer (NaBr) showed that the expelled solution was a mixture of added solution and solution that preexisted in the soil. Comparisons of expelled solution concentrations with concentrations of soil solutions collected by zero-tension and

  3. Laboratory studies of interaction between trace gases and sulphuric acid or sulphate aerosols using flow-tube reactors

    NASA Astrophysics Data System (ADS)

    Leu, Ming-Taun

    Stratospheric ozone provides a protective shield for humanity and the global biosphere from harmful ultraviolet solar radiation. In past decades, theoretical models for the calculation of ozone balance frequently used gas-phase reactions alone in their studies. Since the discovery of the Antarctic ozone hole in 1985, however, it has been demonstrated that knowledge of heterogeneous reactions is needed to understand this significant natural event owing to the anthropogenic emission of chlorofluorocarbons. In this review I will briefly discuss the experimental techniques for the research of heterogeneous chemistry carried out in our laboratory. These experimental instruments include flow-tube reactors, an electron-impact ionization mass spectrometer, a chemical ionization mass spectrometer and a scanning mobility particle spectrometer. Numerous measurements of uptake coefficient (or reaction probability) and solubility of trace gases in liquid sulphuric acid have been performed under the ambient conditions in the upper troposphere and lower stratosphere, mainly 190-250 K and 40-80 wt% of H

  4. Glyphosate and aminomethylphosphonic acid chronic risk assessment for soil biota.

    PubMed

    von Mérey, Georg; Manson, Philip S; Mehrsheikh, Akbar; Sutton, Peter; Levine, Steven L

    2016-11-01

    Glyphosate is a broad-spectrum herbicide used widely in agriculture, horticulture, private gardens, and public infrastructure, where it is applied to areas such as roadsides, railway tracks, and parks to control the growth of weeds. The exposure risk from glyphosate and the primary soil metabolite aminomethylphosphonic acid (AMPA) on representative species of earthworms, springtails, and predatory soil mites and the effects on nitrogen-transformation processes by soil microorganisms were assessed under laboratory conditions based on internationally recognized guidelines. For earthworms, the reproductive no-observed-effect concentration (NOEC) was 472.8 mg glyphosate acid equivalent (a.e.)/kg dry soil, which was the highest concentration tested, and 198.1 mg/kg dry soil for AMPA. For predatory mites, the reproductive NOEC was 472.8 mg a.e./kg dry soil for glyphosate and 320 mg/kg dry soil for AMPA, the highest concentrations tested. For springtails, the reproductive NOEC was 472.8 mg a.e./kg dry soil for glyphosate and 315 mg/kg dry soil for AMPA, the highest concentrations tested. Soil nitrogen-transformation processes were unaffected by glyphosate and AMPA at 33.1 mg a.e./kg soil and 160 mg/kg soil, respectively. Comparison of these endpoints with worst-case soil concentrations expected for glyphosate (6.62 mg a.e./kg dry soil) and AMPA (6.18 mg/kg dry soil) for annual applications at the highest annual rate of 4.32 kg a.e./ha indicate very low likelihood of adverse effects on soil biota. Environ Toxicol Chem 2016;35:2742-2752. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

  5. 1H-n.m.r. investigation of naturally occurring and chemically oversulphated dermatan sulphates. Identification of minor monosaccharide residues.

    PubMed Central

    Bossennec, V; Petitou, M; Perly, B

    1990-01-01

    The 1H-n.m.r. spectra of various dermatan sulphate preparations present, besides the major signals of the basic disaccharide unit, several other minor signals. We have assigned most of them by n.m.r., using two-dimensional proton-proton double-quantum-correlation and nuclear-Overhauser-effect spectroscopy experiments. This allowed us to identify 2-O-sulphated L-iduronic acid and D-glucuronic acid residues as well as 6-sulphated N-acetylgalactosamine (presumably 4-O-sulphated as well). 2-O-Sulphated iduronic acid was present to similar extents (6-10% of total uronic acids) in pig skin dermatan sulphate and pig intestine dermatan sulphate, whereas glucuronic acid represented 17% of the uronic acid of pig skin dermatan sulphate and was virtually absent (1%) from the other preparation. 6-O-Sulphated N-acetylgalactosamine was present in minor amounts in pig intestine dermatan sulphate only. The influence of sulphation of iduronic acid units on their conformation was assessed by using chemically oversulphated pig intestine dermatan sulphate. Introduction of sulphate groups in this unit in dermatan sulphate tends to shift the conformational equilibrium towards the 1C4 conformer. PMID:2339978

  6. Influence of humic acid applications on soil physicochemical properties

    NASA Astrophysics Data System (ADS)

    Gümüş, İ.; Şeker, C.

    2015-09-01

    Soil structure is often said to be the key to soil productivity since a fertile soil, with desirable soil structure and adequate moisture supply, constitutes a productive soil. Soil structure influences soil water movement and retention, erosion, crusting, nutrient recycling, root penetration and crop yield. The objective of this work is to study, humic acid (HA) application on some physical and chemical properties in weak structured soils investigated. The approach involved establishing a plot experiment in the laboratory conditions. Different rates of HA (control, 0.5, 1, 2 and 4 %) were applied to soil at three incubation periods (21, 42 and 62 days). At the end of the each incubation period, the changes in physicochemical properties were measured. Generally, HA addition increased EC values at the all incubation periods. HA applications decreased soil modulus of rupture. Application of HA at the rate of 4 % was significantly increased soil organic carbon contents. HA applications at the rate of 4 % significantly increased both mean soil total nitrogen content and aggregate stability after at three incubation periods (p < 0.05). Therefore, HA was potential to improve structure of soil in short term.

  7. Acid soils of western Serbia and their further acidification

    NASA Astrophysics Data System (ADS)

    Mrvic, Vesna

    2010-05-01

    Acid soils cause many unfavorable soil characteristics from the plant nutrition point of view. Because of increased soil acidity the violation of buffering soil properties due to leaching of Ca and Mg ions is taking place that also can cause soil physical degradation via peptization of colloids. Together with increasing of soil acidity the content of mobile Al increases that can be toxic for plants. Easily available nutritive elements transforms into hardly avaialble froms. The process of deactivation is especially expressed for phosphorous that under such conditions forms non-soluble compounds with sesqui-oxides. From the other hand the higher solubility of some microelements (Zn and B) can cause their accelerated leaching from root zone and therefore, result in their deficiency for plant nutrition. Dangerous and toxic matters transforms into easly-available forms for plants, especially, Cd and Ni under the lower soil pH. The studied soil occupies 36675 hectare in the municipality of Krupan in Serbia, and are characterized with very unfavorable chemical properties: 26% of the territory belongs to the cathegory of very acidic, and 44 % belongs to the cathegory of acidic. The results showed that the soil of the territory of Krupan is limited for agricultural land use due to their high acidity. Beside the statement of negative soil properties determined by acidity, there is a necessity for determination of soil sensitivity for acidification processes toward soil protection from ecological aspect and its prevention from further acidification. Based on such data and categorization of soils it is possible to undertake proper measures for soil protection and melioration of the most endangered soil cover, where the economic aspect of these measures is very important. One of the methods of soil classification based on sensitivity for acidification classification the determination of soil categories is based on the values of soil CEC and pH in water. By combination of these

  8. Using marble wastes as a soil amendment for acidic soil neutralization.

    PubMed

    Tozsin, Gulsen; Arol, Ali Ihsan; Oztas, Taskin; Kalkan, Ekrem

    2014-01-15

    One of the most important factors limiting plant growth is soil pH. The objective of this study is to determine the effectiveness of marble waste applications on neutralization of soil acidity. Marble quarry waste (MQW) and marble cutting waste (MCW) were applied to an acid soil at different rates and their effectiveness on neutralization was evaluated by a laboratory incubation test. The results showed that soil pH increased from 4.71 to 6.36 and 6.84 by applications of MCW and MQW, respectively. It was suggested that MQW and MCW could be used as soil amendments for the neutralization of acid soils and thus the negative impact of marble wastes on the environment could be reduced.

  9. Reduction of DNA fragmentation and hydroxyl radical production by hyaluronic acid and chondroitin-4-sulphate in iron plus ascorbate-induced oxidative stress in fibroblast cultures.

    PubMed

    Campo, Giuseppe M; Avenoso, Angela; Campo, Salvatore; D'Ascola, Angela; Ferlazzo, Alida M; Calatroni, Alberto

    2004-06-01

    Glycosaminoglycans (GAGs), components of extracellular matrix, are thought to play important roles in cell proliferation and differentiation in the repair process of injured tissue. Oxidative stress is one of the most frequent causes of tissue and cell injury and the consequent lipid peroxidation is the main manifestation of free radical damage. It has been found to play an important role in the evolution of cell death. Since several reports have shown that hyaluronic acid (HYA) and chondroitin-4-sulphate (C4S) are able to inhibit lipid peroxidation during oxidative stress, We investigated the antioxidant capacity of these GAGs in reducing oxidative damage in fibroblast cultures. Free radicals production was induced by the oxidizing system employing iron (Fe2+) plus ascorbate. We evaluated cell death, membrane lipid peroxidation, DNA damage, protein oxidation, hydroxyl radical (OH*) generation and endogenous antioxidant depletion in human skin fibroblast cultures. The exposition of fibroblasts to FeSO4 and ascorbate caused inhibition of cell growth and cell death, increased OH* production determined by the aromatic trap method; furthermore it caused DNA strand breaks and protein oxidation as shown by the DNA fragments analysis and protein carbonyl content, respectively. Moreover, it enhanced lipid peroxidation evaluated by the analysis of conjugated dienes (CD) and decreased antioxidant defenses assayed by means of measurement of superoxide dismutase (SOD) and catalase (CAT) activities. When fibroblasts were treated with two different doses of HYA or C4S a protective effect, following oxidative stress induction, was shown. In fact these GAGs were able to limit cell death, reduced DNA fragmentation and protein oxidation, decreased OH* generation, inhibited lipid peroxidation and improved antioxidant defenses. Our results confirm the antioxidant activity of HYA and C4S and this could represent a useful step in the understanding of the exact role played by GAGs in

  10. Intestinal anti-inflammatory activity of apigenin K in two rat colitis models induced by trinitrobenzenesulfonic acid and dextran sulphate sodium.

    PubMed

    Mascaraque, Cristina; González, Raquel; Suárez, María Dolores; Zarzuelo, Antonio; Sánchez de Medina, Fermín; Martínez-Augustin, Olga

    2015-02-28

    Flavonoids are polyphenolic compounds that are widespread in nature, and consumed as part of the human diet in significant amounts. The aim of the present study was to test the intestinal anti-inflammatory activity of apigenin K, a soluble form of apigenin, in two models of rat colitis, namely the trinitrobenzenesulfonic acid (TNBS) model and the dextran sulphate sodium (DSS) model. Apigenin K (1, 3 and 10 mg/kg; by the oral route; n 4-6 per group) was administered as a pre-treatment to rats with TNBS and DSS colitis, and colonic status was checked by macroscopic and biochemical examination. Apigenin K pre-treatment resulted in the amelioration of morphological signs and biochemical markers in the TNBS model. The results demonstrated a reduction in the inflamed area, as well as lower values of score and colonic weight:length ratio compared with the TNBS group. Myeloperoxidase (MPO) activity was reduced by 30 % (P< 0·05). Moreover, apigenin K pre-treatment ameliorated morphological signs and biochemical markers in the DSS model. Thus, macroscopic damage was significantly reduced and the colonic weight:length ratio was lowered by approximately 10 %, while colonic MPO and alkaline phosphatase activities were decreased by 35 and 21 %, respectively (P< 0·05). Apigenin K pre-treatment also tended to normalise the expression of a number of colonic inflammatory markers (e.g. TNF-α, transforming growth factor-β, IL-6, intercellular adhesion molecule 1 or chemokine (C-C motif) ligand 2). In conclusion, apigenin K is found to have anti-inflammatory effects in two preclinical models of inflammatory bowel disease.

  11. Acid rains`s dirty business: Stealing minerals from soil

    SciTech Connect

    Kaiser, J.

    1996-04-12

    This article describes the hidden environmental effects of acid rain - leaching of base mineral ions from the soil, often changing soil chemistry dramatically. The primary information comes from Ecosystem studies at Hubbard Brook of Likens and Buso. The article also discusses both other opinions and possible solutions.

  12. Compost effect on soil humic acid: A NMR study.

    PubMed

    Adani, Fabrizio; Genevini, Pierluigi; Tambone, Fulvia; Montoneri, Enzo

    2006-11-01

    The humic acid (HA) fraction of a food and vegetable residues compost (CM) was taken as indicator to trace the fate of CM organic matter in four years CM amended soil. (1)H and (13)C NMR spectroscopy were used to investigate the nature of the HA isolates from CM, control soil (S(4)) and amended soil. The result indicated a significant structural difference between CM HA and S(4) HA, and supported the presence of both HA fractions in soil at the end of the amendment trials. However, the nature and content of CM HA in soil did not fully explain the increase of soil cation exchange capacity (CEC) after amendment. All CM humic fractions (i.e., fulvic acid, humic acid and humin) were found to contribute to the change of the soil organic matter composition. It is concluded that although CM HA is a suitable indicator of the survival of compost organic matter in soil during amendment, all three humic fractions should be monitored and analyzed to fully understand changes in the composition and properties of amended soil.

  13. Comparison of classic with novel in situ extraction of soil amino acids from grassland soil

    NASA Astrophysics Data System (ADS)

    Chen, J.; Williams, D. G.

    2012-12-01

    Characterization of organic and inorganic soil nitrogen availability is important for determining ecosystem response to global change, as nitrogen limitation is often a major constraint on ecosystem productivity. Classic methods of soil nitrogen extraction involve field collection of soil samples and disturbance of soil aggregates during processing. A novel method of soil amino acid extraction is described that allows the collection of semi-sterile soil water extracts in situ with minimal disturbance to soils. Comparison of samples collected using this novel method to samples collected in parallel using classic methods developed by Brookes et al. 1985 and Kielland 1994 revealed different detectable amino acid N pools relative to ammonium. Glutamate and arginine comprised the highest amino acid N pools from extracts collected from a semiarid grassland site using this new method of extraction. In contrast, samples collected and extracted using the classic method contained higher relative levels of serine, glycine and glutamate. The amounts of dominant amino acids relative to ammonium were significantly greater using the classic method compared to the new method. These observed higher ratios of amino acids to ammonium are likely the result of additional amino acid inputs by lysis of microorganisms which are not removed when filtering in the classic method. Disturbance associated with classic methods of soil N determination may have led to alterations in the quantity and distribution of ammonium and amino acids in extracts. Minimizing disturbance of soil aggregates when sampling nitrogen pools and selection of an appropriate filter for collecting free amino acids may be important for accurately determining nitrogen availability to plant roots and soil microbes.

  14. In situ sulphate stimulation of mercury methylation in a boreal peatland: Toward a link between acid rain and methylmercury contamination in remote environments

    NASA Astrophysics Data System (ADS)

    Branfireun, Brian A.; Roulet, Nigel T.; Kelly, Carol. A.; Rudd, John W. M.

    1999-09-01

    Recent studies have found that "pristine" peatlands have high peat and pore water methylmercury (MeHg) concentrations and that peatlands may act as large sources of MeHg to the downstream aquatic system, depending upon the degree of hydrologie connectivity and catchment physiography. Sulphate-reducing bacteria have been implicated as principal methylators of inorganic mercury in many environments with previous research focused primarily on mercury methylation in aquatic sediments. Experiments in a poor fen in the Experimental Lakes Area, northwestern Ontario, Canada, demonstrated that the in situ addition of sulphate to peat and peat pore water resulted in a significant increase in pore water MeHg concentrations. As peatlands cover a large area of the Northern Hemisphere, this finding has potentially far ranging implications for the global mercury cycle, particularly in areas impacted by anthropogenically derived sulphate where the methylmercury fraction of total mercury species may be much larger than in nonimpacted environments.

  15. The transport of sulphate and sulphite in rat liver mitochondria.

    PubMed

    Crompton, M; Palmieri, F; Capano, M; Quagliariello, E

    1974-07-01

    1. The mechanism of sulphite and sulphate permeation into rat liver mitochondria was investigated. 2. Extramitochondrial sulphite and sulphate elicit efflux of intramitochondrial phosphate, malate, succinate and malonate. The sulphate-dependent effluxes and the sulphite-dependent efflux of dicarboxylate anions are inhibited by butylmalonate, phenylsuccinate and mersalyl. Inhibition of the phosphate efflux produced by sulphite is caused by mersalyl alone and by N-ethylmaleimide and butylmalonate when present together. 3. External sulphite and sulphate cause efflux of intramitochondrial sulphate, and this is inhibited by butylmalonate, phenylsuccinate and mersalyl. 4. External sulphite and sulphate do not cause efflux of oxoglutarate or citrate. 5. Mitochondria swell when suspended in an iso-osmotic solution of ammonium sulphite; this is not inhibited by N-ethylmaleimide or mersalyl. 6. Low concentrations of sulphite, but not sulphate, produce mitochondrial swelling in iso-osmotic solutions of ammonium malate, succinate, malonate, sulphate, or phosphate in the presence of N-ethylmaleimide. 7. It is concluded that both sulphite and sulphate may be transported by the dicarboxylate carrier of rat liver mitochondria and also that sulphite may permeate by an additional mechanism; the latter may involve the permeation of sulphurous acid or SO(2) or an exchange of the sulphite anion for hydroxyl ion(s).

  16. The transport of sulphate and sulphite in rat liver mitochondria

    PubMed Central

    Crompton, M.; Palmieri, F.; Capano, Michela; Quagliariello, E.

    1974-01-01

    1. The mechanism of sulphite and sulphate permeation into rat liver mitochondria was investigated. 2. Extramitochondrial sulphite and sulphate elicit efflux of intramitochondrial phosphate, malate, succinate and malonate. The sulphate-dependent effluxes and the sulphite-dependent efflux of dicarboxylate anions are inhibited by butylmalonate, phenylsuccinate and mersalyl. Inhibition of the phosphate efflux produced by sulphite is caused by mersalyl alone and by N-ethylmaleimide and butylmalonate when present together. 3. External sulphite and sulphate cause efflux of intramitochondrial sulphate, and this is inhibited by butylmalonate, phenylsuccinate and mersalyl. 4. External sulphite and sulphate do not cause efflux of oxoglutarate or citrate. 5. Mitochondria swell when suspended in an iso-osmotic solution of ammonium sulphite; this is not inhibited by N-ethylmaleimide or mersalyl. 6. Low concentrations of sulphite, but not sulphate, produce mitochondrial swelling in iso-osmotic solutions of ammonium malate, succinate, malonate, sulphate, or phosphate in the presence of N-ethylmaleimide. 7. It is concluded that both sulphite and sulphate may be transported by the dicarboxylate carrier of rat liver mitochondria and also that sulphite may permeate by an additional mechanism; the latter may involve the permeation of sulphurous acid or SO2 or an exchange of the sulphite anion for hydroxyl ion(s). PMID:4441366

  17. Acid soil indicators in forest soils of the Cherry River Watershed, West Virginia.

    PubMed

    Farr, C; Skousen, J; Edwards, P; Connolly, S; Sencindiver, J

    2009-11-01

    Declining forest health has been observed during the past several decades in several areas of the eastern USA, and some of this decline is attributed to acid deposition. Decreases in soil pH and increases in soil acidity are indicators of potential impacts on tree growth due to acid inputs and Al toxicity. The Cherry River watershed, which lies within the Monongahela National Forest in West Virginia, has some of the highest rates of acid deposition in Appalachia. East and West areas within the watershed, which showed differences in precipitation, stream chemistry, and vegetation composition, were compared to evaluate soil acidity conditions and to assess their degree of risk on tree growth. Thirty-one soil pits in the West area and 36 pits in the East area were dug and described, and soil samples from each horizon were analyzed for chemical parameters. In A horizons, East area soils averaged 3.7 pH with 9.4 cmol(c) kg(-1) of acidity compared to pH 4.0 and 6.2 cmol(c) kg(-1) of acidity in West area soils. Extractable cations (Ca, Mg, and Al) were significantly higher in the A, transition, and upper B horizons of East versus West soils. However, even with differences in cation concentrations, Ca/Al molar ratios were similar for East and West soils. For both sites using the Ca/Al ratio, a 50% risk of impaired tree growth was found for A horizons, while a 75% risk was found for deeper horizons. Low concentrations of base cations and high extractable Al in these soils translate into a high degree of risk for forest regeneration and tree growth after conventional tree harvesting.

  18. Soil Bacteria Take Up D-Amino Acids, Protect Plants

    NASA Astrophysics Data System (ADS)

    Sun, H. J.; Zhang, G.

    2011-12-01

    Recently, many groups reported D-amino acid uptake by plant roots, raising the question of whether soil D-amino acids represent a source of nitrogen or a source of toxicity. The discussion needs to be placed in the context of competition with rhizosphere bacteria. To provide this context, we followed the concentrations of D- and L-enantiomers of alanine, glutamic acid, aspartic acid, and leucine after they were added to soils in the laboratory. In all cases, the uptake of L-enantiomer began immediately and proceeded rapidly until exhausted. In contrast, the uptake of D-enantiomer required induction: an initial period of inactivity followed by rapid consumption comparable in rate to L-enantiomer. The induced nature of the D activity was confirmed by the addition of rifampicin, an mRNA synthesis inhibitor. Preventing the synthesis of new enzymes abolished soil flora's ability to consume D-amino acids, but not L-amino acids. These results suggest that inducible special racemase enzymes, which can convert D-amino acids back to their native L-forms, are widespread among soil microorganisms. This finding does not rule out the possibility that some plants may out-compete microorganisms and be able to access D-amino acids. It does suggest, however, that rhizosphere bacteria can shield plants from the toxic effect of D-amino acids.

  19. Long-term changes in acidity and DOC in throughfall and soil water in Finnish forests.

    PubMed

    Ukonmaanaho, Liisa; Starr, Mike; Lindroos, Antti-Jussi; Nieminen, Tiina M

    2014-11-01

    The main objective of this study was to examine if any detectable trends in dissolved organic carbon (DOC), sulphate (SO4-S) concentrations and acid neutralizing capacity (ANC) in throughfall (TF) and soil water (SW) could be found during 1990-2010 and to relate them to recent changes in decreased acid deposition. The study was conducted in seven boreal coniferous forest sites: four of which are managed and three unmanaged forests sites. Generally, temporal trend showed a significant decrease in SO4-S concentrations in bulk precipitation (BP), TF and SW. At some of the sites, there was an increasing tendency in BP and TF in the DOC concentrations. This feature coincides with decreasing SO4-S concentration, indicating that SO4-S may be an important driver of DOC release from the canopy. However, a slightly increased temperature, larger senescing needle mass and consequently increased decaying activity in the canopy may partly explain the increasing trend in DOC. In SW, no consistent DOC trend was seen. At some sites, the decreased base cation concentrations mostly account for the decrease in the ANC values in SW and TF.

  20. Zinc sulphate in rheumatoid arthritis

    PubMed Central

    Mattingly, P. C.; Mowat, A. G.

    1982-01-01

    To assess the antirheumatic activity of zinc sulphate, 27 patients with active rheumatoid arthritis took part in a 6-month, randomised, double-blind, between-group trial of oral zinc sulphate versus placebo. Twelve patients on zinc and 9 on placebo completed the trial, but no significant antirheumatic activity of zinc sulphate was demonstrated. PMID:6751243

  1. Arsenic removal from contaminated soil using phosphoric acid and phosphate.

    PubMed

    Zeng, Min; Liao, Bohan; Lei, Ming; Zhang, Yong; Zeng, Qingru; Ouyang, Bin

    2008-01-01

    Laboratory batch experiments were conducted to study arsenic (As) removal from a naturally contaminated soil using phosphoric acid (H3PO4) and potassium dihydrogen phosphate (KH2PO4). Both H3PO4 and KH2PO4 proved to reduce toxicity of the soil in terms of soil As content, attaining more than 20% As removal at a concentration of 200 mmol/L. At the same time, acidification of soil and dissolution of soil components (Ca, Mg, and Si) resulted from using these two extractants, especially H3PO4. The effectiveness of these two extractants could be attributed to the replacement of As by phosphate ions (PO4(3-)). The function of H3PO4 as an acid to dissolve soil components had little effects on As removal. KH2PO4 almost removed as much As as H3PO4, but it did not result in serious damage to soils, indicating that it was a more promising extractant. The results of a kinetic study showed that As removal reached equilibrium after incubation for 360 min, but dissolution of soil components, especially Mg and Ca, was very rapid. Therefore dissolution of soil components would be inevitable if As was further removed. Elovich model best described the kinetic data of As removal among the four models used in the kinetic study.

  2. Effect of selected soil conditioners on soil properties, erosion, runoff, and rye growth in nonfertile acid soil

    USDA-ARS?s Scientific Manuscript database

    Construction operations result in highly disturbed soil, vulnerable to erosion and excess runoff and sediment loads. Limited information exists about effects of erosion mitigation practices on soil and runoff properties in low fertility acidic sites. The current study evaluates the use of polyacry...

  3. Biochar impacts soil microbial community composition and nitrogen cycling in an acidic soil planted with rape.

    PubMed

    Xu, Hui-Juan; Wang, Xiao-Hui; Li, Hu; Yao, Huai-Ying; Su, Jian-Qiang; Zhu, Yong-Guan

    2014-08-19

    Biochar has been suggested to improve acidic soils and to mitigate greenhouse gas emissions. However, little has been done on the role of biochar in ameliorating acidified soils induced by overuse of nitrogen fertilizers. In this study, we designed a pot trial with an acidic soil (pH 4.48) in a greenhouse to study the interconnections between microbial community, soil chemical property changes, and N2O emissions after biochar application. The results showed that biochar increased plant growth, soil pH, total carbon, total nitrogen, C/N ratio, and soil cation exchange capacity. The results of high-throughput sequencing showed that biochar application increased α-diversity significantly and changed the relative abundances of some microbes that are related with carbon and nitrogen cycling at the family level. Biochar amendment stimulated both nitrification and denitrification processes, while reducing N2O emissions overall. Results of redundancy analysis indicated biochar could shift the soil microbial community by changing soil chemical properties, which modulate N-cycling processes and soil N2O emissions. The significantly increased nosZ transcription suggests that biochar decreased soil N2O emissions by enhancing its further reduction to N2.

  4. Effect of Humic Acids and pesticides on Agricultural Soil Structure and Stability and Its Implication on Soil Quality

    NASA Astrophysics Data System (ADS)

    Gaonkar, O. D.; Nambi, I. M.; G, S. K.

    2016-12-01

    The functional and morphological aspects of soil structure determine the soil quality. The dispersion of colloidal soil particles, especially the clay fraction and rupture of soil aggregates, both of which play an important role in soil structure development, lead to degradation of soil quality. The main objective of this work was to determine the effect of behaviour of soil colloids on the agricultural soil structure and quality. The effect of commercial humic acid, organophosphate pesticides and soil natural organic matter on the electrical and structural properties of the soil colloids was also studied. Agricultural soil, belonging to the sandy loam texture class from northern part of India was considered in this study. In order to understand the changes in the soil quality in the presence and absence of humic acids, the soil fabric and structure was analyzed by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM). Electrical properties of natural soil colloids in aqueous suspensions were assessed by zeta potential measurements at varying pH values with and without the presence of humic acids and pesticides. The influence of natural organic matter was analyzed by oxidizing the natural soil organic matter with hydrogen peroxide. The zeta potential of the soil colloids was found to be negative in the pH range studied. The results indicated that hydrogen peroxide treatment lead to deflocculation of colloidal soil particles. In addition, the humic acids undergoes effective adsorption onto the soil surface imparting more negative zeta potential to the colloidal soil particles. The soil hydrophilicity decreased in the presence of humic acids which was confirmed by surface free energy determination. Thus, it can be concluded that the presence of humic acids altered the soil fabric and structure, thereby affecting the soil quality. This study assumes significance in understanding the soil aggregation and the

  5. A three-dimensional model study of methanesulphonic acid to non sea salt sulphate ratio at mid and high-southern latitudes

    NASA Astrophysics Data System (ADS)

    Castebrunet, H.; Martinerie, P.; Genthon, C.; Cosme, E.

    2009-12-01

    The Antarctic and sub-Antarctic methanesulphonic acid (MSA) to non sea salt sulphate (nssSO4) ratio is simulated with the Laboratoire de Météorologie Dynamique Atmospheric General Circulation Model including an atmospheric sulphur chemistry module. Spatial variations of the MSA/nssSO4 ratio in different regions have been suggested to be mostly dependent on temperature or sulphur source contributions. Its past variations in ice cores have been interpreted as related to the DMS precursor source location. Our model results are compared with available field measurements in the Antarctic and sub-Antarctic regions. This suggests that the MSA/nssSO4 ratio in the extra-tropical south hemisphere is mostly dependent on the relative importance of various DMS oxidation pathways. In order to evaluate the effect of a rapid conversion of dimethyl sulphoxide (DMSO) into MSA, not implemented in the model, the MSA+DMSO to nssSO4 ratio is also discussed. Using this modified ratio, the model mostly captures the seasonal variations of MSA/nssSO4 at mid and high-southern latitudes. In addition, the model qualitatively reproduces the bell shaped meridional variations of the ratio, which is highly dependent on the adopted relative reaction rates for the DMS+OH addition and abstraction pathways, and on the assumed reaction products of the MSIA+OH reaction. MSA/nssSO4 ratio in Antarctic snow is fairly well reproduced except at the most inland sites characterized with very low snow accumulation rates. Our results also suggest that atmospheric chemistry plays an important role in the observed decrease of the ratio in snow between coastal regions and central Antarctica. The still insufficient understanding of the DMS oxidation scheme limits our ability to model the MSA/nssSO4 ratio. Specifically, reaction products of the MSIA+OH reaction should be better quantified, and the impact of a fast DMSO conversion to MSA in spring to fall over Antarctica should be evaluated. A better understanding

  6. A three-dimensional model study of methanesulphonic acid to non sea salt sulphate ratio at mid and high-southern latitudes

    NASA Astrophysics Data System (ADS)

    Castebrunet, H.; Martinerie, P.; Genthon, C.; Cosme, E.

    2009-07-01

    The Antarctic and sub-Antarctic methanesulphonic acid (MSA) to non sea salt sulphate (nssSO4) ratio is simulated with the Laboratoire de Météorologie Dynamique Atmospheric General Circulation Model including an atmospheric sulphur chemistry module. Spatial variations of the MSA/nssSO4 ratio in different regions have been suggested to be mostly dependent on temperature or sulphur source contributions. Its past variations in ice cores have been interpreted as related to the DMS precursor source location. Our model results are compared with available field measurements in the Antarctic and sub-Antarctic regions. This suggests that the MSA/nssSO4 ratio in the extra-tropical south hemisphere is mostly dependent on the relative importance of various DMS oxidation pathways. In order to evaluate the effect of a rapid conversion of dimethyl sulphoxide (DMSO) into MSA, not implemented in the model, the MSA+DMSO to nssSO4 ratio is also discussed. Using this modified ratio, the model mostly captures the seasonal variations of MSA/nssSO4 at mid and high-southern latitudes. In addition, the model qualitatively reproduces the bell shaped meridional variations of the ratio, which is highly dependent on the adopted relative reaction rates for the DMS+OH addition and abstraction pathways, and on the assumed reaction products of the MSIA+OH reaction. MSA/nssSO4 ratio in Antarctic snow is fairly well reproduced except at the most inland sites characterized with very low snow accumulation rates. Our results also suggest that atmospheric chemistry plays an important role in the observed decrease of the ratio in snow between coastal regions and central Antarctica. The still insufficient understanding of the DMS oxidation scheme limits our ability to model the MSA/nssSO4 ratio. Specifically, reaction products of the MSIA+OH reaction should be better quantified, and the impact of a fast DMSO conversion to MSA in spring to fall over Antarctica should be evaluated. Direct measurements of

  7. Effects of pig slurry application on soils and soil humic acids.

    PubMed

    Plaza, César; Senesi, Nicola; García-Gil, Juan C; Brunetti, Gennaro; D'Orazio, Valeria; Polo, Alfredo

    2002-08-14

    The effect of three annually consecutive additions of pig slurry at two rates (90 and 150 m3 x ha(-1) x year(-1) on soils and soil humic acids (HAs) was investigated in a field experiment under semiarid conditions. Soils and pig slurries were analyzed by standard methods. The HAs were isolated from soils and pig slurry by a conventional procedure based on alkaline extraction, acidic precipitation to pH 1, purification by repeated alkaline dissolutions and acidic precipitations, water washing, dialysis, and final freeze-drying. The HAs obtained were analyzed for elemental (C, H, N, S, and O) and acidic functional group (carboxylic and phenolic) composition, and by UV-vis, FT-IR, fluorescence, and ESR spectroscopies. With respect to the control soil, the pig slurry amended soils had greater pH and electrical conductivity, slightly larger total N content, and smaller values of C/N ratio. A decrease of total organic C was observed only in soils amended for 2 and 3 years at the higher slurry rate. With respect to control soil HA, pig slurry HA was characterized by larger contents of S- and N-containing groups, smaller acidic functional group and organic free radical contents, a prevalent aliphatic character, extended molecular heterogeneity, and smaller aromatic polycondensation and humification degrees. Amendment with pig slurry HA determines a number of modifications in soil HAs, including increase of C, S, and COOH contents, C/N ratios, and aliphaticity and decrease of extraction yields and N, O, phenolic OH, and organic free radical contents. These effects are generally more evident after the first year of slurry application and tend to disappear with increasing number of treatments. Most probably, over the years the slightly humified slurry HA is mineralized through extended microbial oxidation, whereas only the most recalcitrant components, such as S-containing, phenolic, and aliphatic structures, are partially accumulated by incorporation into soil HA.

  8. Amelioration of acidic soil using various renewable waste resources.

    PubMed

    Moon, Deok Hyun; Chang, Yoon-Young; Ok, Yong Sik; Cheong, Kyung Hoon; Koutsospyros, Agamemnon; Park, Jeong-Hun

    2014-01-01

    In this study, improvement of acidic soil with respect to soil pH and exchangeable cations was attempted for sample with an initial pH of approximately 5. Acidic soil was amended with various waste resources in the range of 1 to 5 wt.% including waste oyster shells (WOS), calcined oyster shells (COS), Class C fly ash (FA), and cement kiln dust (CKD) to improve soil pH and exchangeable cations. Upon treatment, the soil pH was monitored for periods up to 3 months. The exchangeable cations were measured after 1 month of curing. After a curing period of 1 month, a maize growth experiment was conducted with selected-treated samples to evaluate the effectiveness of treatment. The treatment results indicate that in order to increase the soil pH to a value of 7, 1 wt.% of WOS, 3 wt.% of FA, and 1 wt.% of CKD are required. In the case of COS, 1 wt.% was more than enough to increase the soil pH value to 7 because of COS's strong alkalinity. Moreover, the soil pH increases after a curing period of 7 days and remains virtually unchanged thereafter up to 1 month of curing. Upon treatment, the summation of cations (Ca, Mg, K, and Na) significantly increased. The growth of maize is superior in the treated samples rather than the untreated one, indicating that the amelioration of acidic soil is beneficial to plant growth, since soil pH was improved and nutrients were replenished.

  9. Soil water samplers in ion balance studies on acidic forest soils

    SciTech Connect

    Rasmussen, L.; Joergensen, P.; Kruse, S.

    1986-04-01

    During the last years an increasing consciousness has appeared of the injurious effects of acid rain on the forest ecosystems both in Europe and North America. At several localities ion balance studies have been implemented in order to evaluate the impact of the atmospheric deposition of acidic substances and heavy metals on the forest ecosystem. In many localities the leaching of material to the ground water or output from the ecosystem has to be determined by means of tensiometer measurements and soil water sampling. Many different soil water samplers are available on the market and they show useful applicability under the given circumstances. But in many cases soil water samples taken with different equipment give incommensurable results leading to differing explanations of the effects of acid precipitation on elements and their cycling in the ecosystem. The purpose of the present study is twofold. Firstly, the sorption characteristics of different types of soil water samplers are examined under acidic soil conditions both by installation in the field and by laboratory experiments. Secondly, a new method is introduced for current and constant soil water sampling under varying soil suctions in the unsaturated zone.

  10. Subcritical Water Extraction of Amino Acids from Atacama Desert Soils

    NASA Technical Reports Server (NTRS)

    Amashukeli, Xenia; Pelletier, Christine C.; Kirby, James P.; Grunthaner, Frank J.

    2007-01-01

    Amino acids are considered organic molecular indicators in the search for extant and extinct life in the Solar System. Extraction of these molecules from a particulate solid matrix, such as Martian regolith, will be critical to their in situ detection and analysis. The goals of this study were to optimize a laboratory amino acid extraction protocol by quantitatively measuring the yields of extracted amino acids as a function of liquid water temperature and sample extraction time and to compare the results to the standard HCl vapor- phase hydrolysis yields for the same soil samples. Soil samples from the Yungay region of the Atacama Desert ( Martian regolith analog) were collected during a field study in the summer of 2005. The amino acids ( alanine, aspartic acid, glutamic acid, glycine, serine, and valine) chosen for analysis were present in the samples at concentrations of 1 - 70 parts- per- billion. Subcritical water extraction efficiency was examined over the temperature range of 30 - 325 degrees C, at pressures of 17.2 or 20.0 MPa, and for water- sample contact equilibration times of 0 - 30 min. None of the amino acids were extracted in detectable amounts at 30 degrees C ( at 17.2 MPa), suggesting that amino acids are too strongly bound by the soil matrix to be extracted at such a low temperature. Between 150 degrees C and 250 degrees C ( at 17.2 MPa), the extraction efficiencies of glycine, alanine, and valine were observed to increase with increasing water temperature, consistent with higher solubility at higher temperatures, perhaps due to the decreasing dielectric constant of water. Amino acids were not detected in extracts collected at 325 degrees C ( at 20.0 MPa), probably due to amino acid decomposition at this temperature. The optimal subcritical water extraction conditions for these amino acids from Atacama Desert soils were achieved at 200 degrees C, 17.2 MPa, and a water- sample contact equilibration time of 10 min.

  11. Phosphoric acid, nitric acid, and hydrogen peroxide digestion of soil and plant materials for selenium determination

    SciTech Connect

    Dong, A.; Rendig, V.V.; Burau, R.G.; Besga, G.S.

    1987-11-15

    A mixture of phosphoric acid, nitric acid, and hydrogen peroxide has been proposed as an alternative to the use of the nitric/perchloric acid mixture to digest biological fluids to determine their selenium (Se) content. The purpose of the studies reported here was to test the applicability of this digestion method for the determination of Se in soil and plant materials.

  12. Effect of humic acid on transformation of soil heavy metals

    NASA Astrophysics Data System (ADS)

    Wu, Shengzhe; Li, Rui; Peng, Shuyang; Liu, Qiuyong; Zhu, Xi

    2017-06-01

    The pattern of transformation among different fractions of heavy metals in soil draws great attention. This article investigated the effect of humic acid on soil heavy metal under different pH and temperature. The results showed that with the increasing of the concentration of humic acid, the concentration of available Cu, Pb decreased greatly, though the decrease of available Cd was light. Also, pH of soil had certain impact on the concentration of available Cu, Pb, Cd while the influence of environmental temperature was minor. The removal efficiency of contaminated soil was 57.283% (Cu), 2.645% (Cd) and 15.485% (Pb) while it could reach more than 98% in contaminated solution.

  13. Transcriptional profile of maize roots under acid soil growth

    PubMed Central

    2010-01-01

    Background Aluminum (Al) toxicity is one of the most important yield-limiting factors of many crops worldwide. The primary symptom of Al toxicity syndrome is the inhibition of root growth leading to poor water and nutrient absorption. Al tolerance has been extensively studied using hydroponic experiments. However, unlike soil conditions, this method does not address all of the components that are necessary for proper root growth and development. In the present study, we grew two maize genotypes with contrasting tolerance to Al in soil containing toxic levels of Al and then compared their transcriptomic responses. Results When grown in acid soil containing toxic levels of Al, the Al-sensitive genotype (S1587-17) showed greater root growth inhibition, more Al accumulation and more callose deposition in root tips than did the tolerant genotype (Cat100-6). Transcriptome profiling showed a higher number of genes differentially expressed in S1587-17 grown in acid soil, probably due to secondary effects of Al toxicity. Genes involved in the biosynthesis of organic acids, which are frequently associated with an Al tolerance response, were not differentially regulated in both genotypes after acid soil exposure. However, genes related to the biosynthesis of auxin, ethylene and lignin were up-regulated in the Al-sensitive genotype, indicating that these pathways might be associated with root growth inhibition. By comparing the two maize lines, we were able to discover genes up-regulated only in the Al-tolerant line that also presented higher absolute levels than those observed in the Al-sensitive line. These genes encoded a lipase hydrolase, a retinol dehydrogenase, a glycine-rich protein, a member of the WRKY transcriptional family and two unknown proteins. Conclusions This work provides the first characterization of the physiological and transcriptional responses of maize roots when grown in acid soil containing toxic levels of Al. The transcriptome profiles highlighted

  14. Nitrate formation in acid forest soils from the Adirondacks

    SciTech Connect

    Klein, T.M.; Kreitinger, J.P.; Alexander, M.

    1983-01-01

    Nitrate formation in three forest soils from the Adirondacks region of New York was studied in the laboratory. The organic and surface mineral layers of the soils has pH values ranging from 3.6 to 4.1. Nitrate was formed when the soils were treated with artificial rain at pH 3.5, 4.1, or 5.6. Compared to simulated rain at pH 5.6, simulated rain at pH 3.5 enhanced nitrate formation in one soil and inhibited it in two other soils. The rate of nitrate accumulation was about 10 times higher in the organic horizon than in the mineral horizon, and nitrate formation was not enhanced by ammonium additions. Nitrate formation in soil suspensions was dependent on the amount of soil in the suspension, and none was formed if little soil was present. Ammonium did not enhance nitrate production in the suspensions. It is suggested that nitrate formation in these acid soils is not limited by the ammonium supply. 19 references, 2 figures, 2 tables.

  15. Field evidence of cadmium phytoavailability decreased effectively by rape straw and/or red mud with zinc sulphate in a Cd-contaminated calcareous soil.

    PubMed

    Li, Bo; Yang, Junxing; Wei, Dongpu; Chen, Shibao; Li, Jumei; Ma, Yibing

    2014-01-01

    To reduce Cd phytoavailability in calcareous soils, the effects of soil amendments of red mud, rape straw, and corn straw in combination with zinc fertilization on Cd extractability and phytoavailability to spinach, tomato, Chinese cabbage and radish were investigated in a calcareous soil with added Cd at 1.5 mg kg-1. The results showed that water soluble and exchangeable Cd in soils was significantly decreased by the amendments themselves from 26% to 70%, which resulted in marked decrease by approximately from 34% to 77% in Cd concentration in vegetables. The amendments plus Zn fertilization further decreased the Cd concentration in vegetables. Also cruciferous rape straw was more effective than gramineous corn straw. In all treatments, rape straw plus red mud combined with Zn fertilization was most effective in decreasing Cd phytoavailability in soils, and it is potential to be an efficient and cost-effective measure to ensure food safety for vegetable production in mildly Cd-contaminated calcareous soils.

  16. The abiotic degradation of soil organic matter to oxalic acid

    NASA Astrophysics Data System (ADS)

    Studenroth, Sabine; Huber, Stefan; Schöler, H. F.

    2010-05-01

    The abiotic degradation of soil organic matter to volatile organic compounds was studied intensely over the last years (Keppler et al., 2000; Huber et al., 2009). It was shown that soil organic matter is oxidised due to the presence of iron (III), hydrogen peroxide and chloride and thereby produces diverse alkyl halides, which are emitted into the atmosphere. The formation of polar halogenated compounds like chlorinated acetic acids which are relevant toxic environmental substances was also found in soils and sediments (Kilian et al., 2002). The investigation of the formation of other polar halogenated and non-halogenated compounds like diverse mono- and dicarboxylic acids is going to attain more and more importance. Due to its high acidity oxalic acid might have impacts on the environment e.g., nutrient leaching, plant diseases and negative influence on microbial growth. In this study, the abiotic formation of oxalic acid in soil is examined. For a better understanding of natural degradation processes mechanistic studies were conducted using the model compound catechol as representative for structural elements of the humic substances and its reaction with iron (III) and hydrogen peroxide. Iron is one of the most abundant elements on earth and hydrogen peroxide is produced by bacteria or through incomplete reduction of oxygen. To find suitable parameters for an optimal reaction and a qualitative and quantitative analysis method the following reaction parameters are varied: concentration of iron (III) and hydrogen peroxide, time dependence, pH-value and influence of chloride. Analysis of oxalic acid was performed employing an ion chromatograph equipped with a conductivity detector. The time dependent reaction shows a relatively fast formation of oxalic acid, the optimum yield is achieved after 60 minutes. Compared to the concentration of catechol an excess of hydrogen peroxide as well as a low concentration of iron (III) are required. In absence of chloride the

  17. Microbiological aspects of determination of trichloroacetic acid in soil.

    PubMed

    Matucha, M; Gryndler, M; Uhlírová, H; Fuksová, K; Rohlenová, J; Forczek, S T; Schröder, P

    2004-01-01

    Soils have been shown to possess a strong microbial trichloroacetic acid (TCA)-degrading activity. High TCA-degradation rate was also observed during soil extraction with water. For correct measurements of TCA levels in soil all TCA-degrading activities have to be inhibited immediately after sampling before analysis. We used rapid freezing of soil samples (optimally in liquid nitrogen) with subsequent storage and slow thawing before analysis as an efficient technique for suppressing the degradation. Frozen soil samples stored overnight at -20 degrees C and then thawed slowly exhibited very low residual TCA-degrading activity for several hours. Omitting the above procedure could lead to the confusing differences between the TCA levels previously reported in the literature.

  18. Searching for bacteriocin-producing lactic acid bacteria in soil.

    PubMed

    Yanagida, Fujitoshi; Chen, Yi-Sheng; Shinohara, Takashi

    2006-02-01

    A survey was conducted on the isolation and characterization of bacteriocin-producing lactic acid bacteria in soil. Forty-two acid-producing bacterial strains were isolated from 55 soil samples collected in Yamanashi prefecture, Japan. Investigation of antibacterial activities of isolates revealed that three isolates, Lactobacillus animalis C060203, Enterococcus durans C102901 and Leuconostoc mesenteroides subsp. mesenteroides C060204, showed antibacterial activities against the indicator strain of Lactobacillus sakei JCM 1157T. Bacteriocin from Enterococcus durans C102901 showed different characteristics from the known durancin L28-1A, produced by Enterococcus durans L28-1. Furthermore, this is the first report of a bacteriocin being produced by Lactobacillus animalis. Viewing from the species, bacteriocins from strains C102901 and C060203 showed high possibilities for the novel substances. These significant findings suggest that soil may be a common source for the isolation of novel bacteriocin-producing lactic acid bacteria.

  19. Role of sulphate in development.

    PubMed

    Dawson, Paul Anthony

    2013-09-01

    Sulphate contributes to numerous processes in mammalian physiology, particularly during development. Sulphotransferases mediate the sulphate conjugation (sulphonation) of numerous compounds, including steroids, glycosaminoglycans, proteins, neurotransmitters and xenobiotics, transforming their biological activities. Importantly, the ratio of sulphonated to unconjugated molecules plays a significant physiological role in many of the molecular events that regulate mammalian growth and development. In humans, the fetus is unable to generate its own sulphate and therefore relies on sulphate being supplied from maternal circulation via the placenta. To meet the gestational needs of the growing fetus, maternal blood sulphate concentrations double from mid-gestation. Maternal hyposulphataemia has been linked to fetal sulphate deficiency and late gestational fetal loss in mice. Disorders of sulphonation have also been linked to a number of developmental disorders in humans, including skeletal dysplasias and premature adrenarche. While recognised as an important nutrient in mammalian physiology, sulphate is largely unappreciated in clinical settings. In part, this may be due to technical challenges in measuring sulphate with standard pathology equipment and hence the limited findings of perturbed sulphate homoeostasis affecting human health. This review article is aimed at highlighting the importance of sulphate in mammalian development, with basic science research being translated through animal models and linkage to human disorders.

  20. 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.

  1. [The influence of simulated acid rain on acidity and K+ leaching regulation of different soil layers].

    PubMed

    Wang, Daizhang; Jiang, Xin; Bian, Yongrong; Sun, Lei; Li, Rui; He, Jizheng

    2003-03-01

    The influence of simulated acid rain on acidity and K+ release of different soil layers of red soil from Jiangxi was investigated in the lab when surface soil was mixed with KCl. The results indicated that pH of leaching solution first decreased, then increased in the different soil layers, but pH at the beginning moment of leaching existed prominent differences and pH of leachate of pH 2.5 acid rain in A and AB layers again decreased during subsequent stage. There was a peak value of EC of leachate appearing at the beginning stage, it showed that nutrient ions in soil rapidly moved downwards into lower depth of profile. K+ concentration of effluent solution was related to acidity of acid rain and the pH2.5 value of acid rain accelerated K+ transportation downwards along profile. K+ release of A soil layer was divided into two moments which one was the rapid rate of K+ release process at the moment of beginning and then into the middle rate of release process. As to pH 4.5 value of acid rain, it also existed rapid and slow rate processes.

  2. A reexamination of amino acids in lunar soil

    NASA Astrophysics Data System (ADS)

    Brinton, K. L. F.; Bada, J. L.; Arnold, J. R.

    1993-03-01

    Amino acids in lunar soils provide an important indicator of the level of prebiotic organic compounds on the moon. The results provide insight into the chemistry of amino acid precursors, and furthermore, given the flux of carbonaceous material to the moon, we can evaluate the survival of organics upon impact. The amino acid contents of both hydrolyzed and unhydrolyzed hot-water extracts of Apollo 17 lunar soil were determined using ophthaldialdehyde/N-acetyl cysteine (OPA/NAC) derivatization followed by HPLC analysis. Previous studies of lunar amino acids were inconclusive, as the technique used (derivatization with ninhydrin followed by HPLC analysis) was unable to discriminate between cosmogenic amino acids and terrestrial contaminants. Cosmogenic amino acids are racemic, and many of the amino acids found in carbonaceous meteorites such as Murchison, i.e., alpha-amino-i-butyric acid (aib), are extremely rare on Earth. The ninhydrin method does not distinguish amino acid enantiomers, nor does it detect alpha-alkyl amino acids such as aib, whereas the OPA/NAC technique does both.

  3. A reexamination of amino acids in lunar soil

    NASA Technical Reports Server (NTRS)

    Brinton, K. L. F.; Bada, J. L.; Arnold, J. R.

    1993-01-01

    Amino acids in lunar soils provide an important indicator of the level of prebiotic organic compounds on the moon. The results provide insight into the chemistry of amino acid precursors, and furthermore, given the flux of carbonaceous material to the moon, we can evaluate the survival of organics upon impact. The amino acid contents of both hydrolyzed and unhydrolyzed hot-water extracts of Apollo 17 lunar soil were determined using ophthaldialdehyde/N-acetyl cysteine (OPA/NAC) derivatization followed by HPLC analysis. Previous studies of lunar amino acids were inconclusive, as the technique used (derivatization with ninhydrin followed by HPLC analysis) was unable to discriminate between cosmogenic amino acids and terrestrial contaminants. Cosmogenic amino acids are racemic, and many of the amino acids found in carbonaceous meteorites such as Murchison, i.e., alpha-amino-i-butyric acid (aib), are extremely rare on Earth. The ninhydrin method does not distinguish amino acid enantiomers, nor does it detect alpha-alkyl amino acids such as aib, whereas the OPA/NAC technique does both.

  4. A reexamination of amino acids in lunar soil

    NASA Technical Reports Server (NTRS)

    Brinton, K. L. F.; Bada, J. L.; Arnold, J. R.

    1993-01-01

    Amino acids in lunar soils provide an important indicator of the level of prebiotic organic compounds on the moon. The results provide insight into the chemistry of amino acid precursors, and furthermore, given the flux of carbonaceous material to the moon, we can evaluate the survival of organics upon impact. The amino acid contents of both hydrolyzed and unhydrolyzed hot-water extracts of Apollo 17 lunar soil were determined using ophthaldialdehyde/N-acetyl cysteine (OPA/NAC) derivatization followed by HPLC analysis. Previous studies of lunar amino acids were inconclusive, as the technique used (derivatization with ninhydrin followed by HPLC analysis) was unable to discriminate between cosmogenic amino acids and terrestrial contaminants. Cosmogenic amino acids are racemic, and many of the amino acids found in carbonaceous meteorites such as Murchison, i.e., alpha-amino-i-butyric acid (aib), are extremely rare on Earth. The ninhydrin method does not distinguish amino acid enantiomers, nor does it detect alpha-alkyl amino acids such as aib, whereas the OPA/NAC technique does both.

  5. Mid-Infrared Spectroscopic Properties of Humic Acid and Fulvic Acid-Soil Mixtures.

    USDA-ARS?s Scientific Manuscript database

    The detection of humic materials in soils is essential in order to determine organic matter (SOM) stability and C sequestration on agricultural land. Mid-Infrared (MidIR) spectroscopy has been used to characterize SOM quality [1], study extracted soil humic acids [2], develop calibrations for quanti...

  6. Mid-Infrared Spectroscopic Properties of Humic Acid and Fulvic Acid-Soil Mixtures

    USDA-ARS?s Scientific Manuscript database

    The detection of humic materials in soils is essential in order to determine organic matter (SOM) stability and C sequestration on agricultural land. Mid-Infrared (MidIR) spectroscopy has been used to characterize SOM quality [1], study extracted soil humic acids [2], develop calibrations for quanti...

  7. Barren Acidic Soil Assessment using Seismic Refraction Survey

    NASA Astrophysics Data System (ADS)

    Tajudin, S. A. A.; Abidin, M. H. Z.; Madun, A.; Zawawi, M. H.

    2016-07-01

    Seismic refraction method is one of the geophysics subsurface exploration techniques used to determine subsurface profile characteristics. From past experience, seismic refraction method is commonly used to detect soil layers, overburden, bedrock, etc. However, the application of this method on barren geomaterials remains limited due to several reasons. Hence, this study was performed to evaluate the subsurface profile characteristics of barren acidic soil located in Ayer Hitam, Batu Pahat, Johor using seismic refraction survey. The seismic refraction survey was conducted using ABEM Terraloc MK 8 (seismograph), a sledge hammer weighing 7 kg (source) and 24 units of 10 Hz geophones (receiver). Seismic data processing was performed using OPTIM software which consists of SeisOpt@picker (picking the first arrival and seismic configureuration data input) and SeisOpt@2D (generating 2D image of barren acidic soil based on seismic velocity (primary velocity, Vp) distribution). It was found that the barren acidic soil profile consists of three layers representing residual soil (Vp= 200-400 m/s) at 0-2 m, highly to completely weathered soil (Vp= 500-1800 m/s) at 3-8 m and shale (Vp= 2100-6200 m/s) at 9-20 m depth. Furthermore, result verification was successfully done through the correlation of seismic refraction data based on physical mapping and the geological map of the study area. Finally, it was found that the seismic refraction survey was applicable for subsurface profiling of barren acidic soil as it was very efficient in terms of time, cost, large data coverage and sustainable.

  8. A randomized blinded clinical trial of two antivenoms, prepared by caprylic acid or ammonium sulphate fractionation of IgG, in Bothrops and Porthidium snake bites in Colombia: correlation between safety and biochemical characteristics of antivenoms.

    PubMed

    Otero, R; Gutiérrez, J M; Rojas, G; Núñez, V; Díaz, A; Miranda, E; Uribe, A F; Silva, J F; Ospina, J G; Medina, Y; Toro, M F; García, M E; León, G; García, M; Lizano, S; De La Torre, J; Márquez, J; Mena, Y; González, N; Arenas, L C; Puzón, A; Blanco, N; Sierra, A; Espinal, M E; Lozano, R

    1999-06-01

    A randomized blinded clinical trial was performed in 53 patients bitten by Bothrops sp. and Porthidium sp. in Antioquia and Chocó, Colombia, in order to compare the efficacy and safety of two antivenoms made of whole IgG obtained by either ammonium sulphate (monovalent anti-B. atrox) or caprylic acid (polyvalent) fractionation. Additionally, antivenoms were compared by electrophoretic and chromatographic analyses and anticomplementary activity in vitro. With a protocol of 2, 4 and 6 antivenom vials for the treatment of mild, moderate and severe envenomings, respectively, both antivenoms were equally efficient to neutralize the most relevant signs of envenoming and to clear serum venom levels in patients from the first hour and later on. Three patients with severe envenoming and initially treated with less than six vials on admission had persistent or recurrent venom antigenemia within 12-48 h. Monovalent antivenom fractionated by ammonium sulphate precipitation had higher amounts of protein aggregates and nonimmunoglobulin proteins than polyvalent antivenom fractionated by caprylic acid precipitation. Both antivenoms presented anticomplementary activity in vitro, being higher in the monovalent product. In agreement, monovalent antivenom induced a significantly higher incidence of early antivenom reactions (52%) than polyvalent antivenom (25%).

  9. Acid-activated biochar increased sulfamethazine retention in soils.

    PubMed

    Vithanage, Meththika; Rajapaksha, Anushka Upamali; Zhang, Ming; Thiele-Bruhn, Sören; Lee, Sang Soo; Ok, Yong Sik

    2015-02-01

    Sulfamethazine (SMZ) is an ionizable and highly mobile antibiotic which is frequently found in soil and water environments. We investigated the sorption of SMZ onto soils amended with biochars (BCs) at varying pH and contact time. Invasive plants were pyrolyzed at 700 °C and were further activated with 30 % sulfuric (SBBC) and oxalic (OBBC) acids. The sorption rate of SMZ onto SBBC and OBBC was pronouncedly pH dependent and was decreased significantly when the values of soil pH increased from 3 to 5. Modeled effective sorption coefficients (K D,eff) values indicated excellent sorption on SBBC-treated loamy sand and sandy loam soils for 229 and 183 L/kg, respectively. On the other hand, the low sorption values were determined for OBBC- and BBC700-treated loamy sand and sandy loam soils. Kinetic modeling demonstrated that the pseudo second order model was the best followed by intra-particle diffusion and the Elovich model, indicating that multiple processes govern SMZ sorption. These findings were also supported by sorption edge experiments based on BC characteristics. Chemisorption onto protonated and ligand containing functional groups of the BC surface, and diffusion in macro-, meso-, and micro-pores of the acid-activated BCs are the proposed mechanisms of SMZ retention in soils. Calculated and experimental q e (amount adsorbed per kg of the adsorbent at equilibrium) values were well fitted to the pseudo second order model, and the predicted maximum equilibrium concentration of SBBC for loamy sand soils was 182 mg/kg. Overall, SBBC represents a suitable soil amendment because of its high sorption rate of SMZ in soils.

  10. Transcriptional response of Medicago truncatula sulphate transporters to arbuscular mycorrhizal symbiosis with and without sulphur stress.

    PubMed

    Casieri, Leonardo; Gallardo, Karine; Wipf, Daniel

    2012-06-01

    Sulphur is an essential macronutrient for plant growth, development and response to various abiotic and biotic stresses due to its key role in the biosynthesis of many S-containing compounds. Sulphate represents a very small portion of soil S pull and it is the only form that plant roots can uptake and mobilize through H(+)-dependent co-transport processes implying sulphate transporters. Unlike the other organically bound forms of S, sulphate is normally leached from soils due to its solubility in water, thus reducing its availability to plants. Although our knowledge of plant sulphate transporters has been growing significantly in the past decades, little is still known about the effect of the arbuscular mycorrhiza interaction on sulphur uptake. Carbon, nitrogen and sulphur measurements in plant parts and expression analysis of genes encoding putative Medicago sulphate transporters (MtSULTRs) were performed to better understand the beneficial effects of mycorrhizal interaction on Medicago truncatula plants colonized by Glomus intraradices at different sulphate concentrations. Mycorrhization significantly promoted plant growth and sulphur content, suggesting increased sulphate absorption. In silico analyses allowed identifying eight putative MtSULTRs phylogenetically distributed over the four sulphate transporter groups. Some putative MtSULTRs were transcribed differentially in roots and leaves and affected by sulphate concentration, while others were more constitutively transcribed. Mycorrhizal-inducible and -repressed MtSULTRs transcripts were identified allowing to shed light on the role of mycorrhizal interaction in sulphate uptake.

  11. Sulphation of proteins secreted by a human hepatoma-derived cell line. Sulphation of N-linked oligosaccharides on alpha 2HS-glycoprotein.

    PubMed Central

    Hortin, G; Green, E D; Baenziger, J U; Strauss, A W

    1986-01-01

    Several human glycoproteins, including alpha 1-antitrypsin, alpha 1-acid glycoprotein, transferrin, caeruloplasmin and alpha 2HS-glycoprotein, synthesized by the hepatoma-derived cell line HepG2 were observed to contain covalently linked sulphate. These proteins were estimated to contain about 0.1 mol of sulphate/mol of protein. The most abundant of the sulphated glycoproteins, alpha 2HS-glycoprotein, was analysed in detail. All of the sulphate on this protein was attached to N-linked oligosaccharides which contained sialic acid and resisted release by endoglycosidase H. Several independent analytical approaches established that approx. 10% of the molecules of alpha 2HS-glycoprotein contained sulphate. Our results suggest that a number of human plasma proteins contain small amounts of sulphate linked to oligosaccharides. Images Fig. 1. Fig. 2. Fig. 3. PMID:3017304

  12. Field Evidence of Cadmium Phytoavailability Decreased Effectively by Rape Straw and/or Red Mud with Zinc Sulphate in a Cd-Contaminated Calcareous Soil

    PubMed Central

    Li, Bo; Yang, Junxing; Wei, Dongpu; Chen, Shibao; Li, Jumei; Ma, Yibing

    2014-01-01

    To reduce Cd phytoavailability in calcareous soils, the effects of soil amendments of red mud, rape straw, and corn straw in combination with zinc fertilization on Cd extractability and phytoavailability to spinach, tomato, Chinese cabbage and radish were investigated in a calcareous soil with added Cd at 1.5 mg kg−1. The results showed that water soluble and exchangeable Cd in soils was significantly decreased by the amendments themselves from 26% to 70%, which resulted in marked decrease by approximately from 34% to 77% in Cd concentration in vegetables. The amendments plus Zn fertilization further decreased the Cd concentration in vegetables. Also cruciferous rape straw was more effective than gramineous corn straw. In all treatments, rape straw plus red mud combined with Zn fertilization was most effective in decreasing Cd phytoavailability in soils, and it is potential to be an efficient and cost-effective measure to ensure food safety for vegetable production in mildly Cd-contaminated calcareous soils. PMID:25303439

  13. Soil Studies: Applying Acid-Base Chemistry to Environmental Analysis.

    ERIC Educational Resources Information Center

    West, Donna M.; Sterling, Donna R.

    2001-01-01

    Laboratory activities for chemistry students focus attention on the use of acid-base chemistry to examine environmental conditions. After using standard laboratory procedures to analyze soil and rainwater samples, students use web-based resources to interpret their findings. Uses CBL probes and graphing calculators to gather and analyze data and…

  14. Soil Studies: Applying Acid-Base Chemistry to Environmental Analysis.

    ERIC Educational Resources Information Center

    West, Donna M.; Sterling, Donna R.

    2001-01-01

    Laboratory activities for chemistry students focus attention on the use of acid-base chemistry to examine environmental conditions. After using standard laboratory procedures to analyze soil and rainwater samples, students use web-based resources to interpret their findings. Uses CBL probes and graphing calculators to gather and analyze data and…

  15. A humic acid extract from lignite for reclaiming contaminated soils

    SciTech Connect

    Barnhisel, R.I.

    1999-07-01

    A unique form of a humic compound was developed by A.I. Shulgin, A.A. Shapovalov and U.G. Putsykin of Moscow, Russia using a patented process from lignite coal. This material appears to have properties that complexes certain heavy metals such as Pb, Cu, Cd, etc. as well as PCB's. This study was restricted to its interaction with Pb. Both greenhouse and laboratory studies were conducted from a quantity of humic acid (Stabilite) from the SET company in Louisville, KY. Although Stabilite contains some Pb, in the laboratory study, significant reductions in Pb concentration occurred. Stabilite also reduced Pb levels of an artificially contaminated soil having 1,000 ppm Pb for both the residual soil as well as water leached through this soil. Corn grown in this did not extract Pb from the Stabilite treated soil.

  16. [Effects of different fertilization treatments on soil humic acid structure characteristics].

    PubMed

    Zhao, Nan; Lü, Yi-Zhong

    2012-07-01

    The present article used soil humic acid as research object to study effects on the structure characteristics of soil humic acid under the condition of applying cake fertilizer, green manure, straw fertilizer with the same contents of nitrogen and phosphorus. It used element analysis, micro infrared, and solid 13C-NMR for structure analysis, the results indicated that: The chemical composition and structure characteristics of humic acids were similar, but they also had many obvious differences. (1) The atomic ratios of H/C, O/C, and C/N were all different for the humic acids, the soil humic acid of cake fertilizer processing had the highest contents of H and N, green manure processing of soil humic acid contained the highest content of O, while straw fertilizer processing of soil humic acid contained highest content of C. (2) Infrared analysis displayed that the three soil humic acids contained protein Cake fertilizer processing of soil humic acid contained the most amino compounds, green manure processing of soil humic acid contained the maximum contents of hydroxyl and aliphatic hydrocarbon, while straw fertilizer processing of soil humic acid contained the highest contents of alcohol and phenol. (3) Solid 13C-NMR data indicated that cake fertilizer processing of soil humic acid contained the most carboxyl carbon, green manure processing of soil humic acid contained the highest contents of alkyl carbon and carbonyl carbon, while straw fertilizer processing of soil humic acids had the most alkoxy carbon and aromatic carbon

  17. Purification and characterization of heparan sulphate proteoglycan from bovine brain.

    PubMed Central

    Park, Y; Yu, G; Gunay, N S; Linhardt, R J

    1999-01-01

    A heparan sulphate proteoglycan was purified from adult bovine brain tissues and its structure was characterized. The major heparan sulphate proteoglycan from whole bovine brain had a molecular mass of >200 kDa on denaturing SDS/PAGE and a core protein size of 66 kDa following the removal of glycosaminoglycan chains. Fractionation on DEAE-Sephacel showed that this proteoglycan consisted of three major forms having high, intermediate and low overall charge. All core proteins were identical in size and reacted with heparan sulphate proteoglycan-stub antibody and an antibody made to a synthetic peptide based on rat glypican. The three forms of proteoglycans had identical peptide maps and their amino acid compositional analysis did not match any of the known glypicans. The internal sequence of a major peptide showed only 37.5% sequence similarity with human glypican 5. The glycosaminoglycan chain sizes of the three forms of this proteoglycan, determined after beta-elimination by PAGE, were identical. The disaccharide compositional analysis on the heparan sulphate chains from the three forms of the proteoglycan, determined by treatment with a mixture of heparin lyases followed by high-resolution capillary electrophoresis, showed that they differed primarily by degree of sulphation. The most highly sulphated proteoglycan isolated had a disaccharide composition similar to heparan sulphate glycosaminoglycans found in brain tissue. Based on their sensitivity to low pH nitrous acid treatment, the N-sulphate groups in these proteoglycans were found to be primarily in the smaller glycosaminoglycan chains. The heparan sulphate proteoglycans were also heavily glycosylated with O-linked glycans and no glycosylphosphatidylinositol anchor could be detected. PMID:10585858

  18. Growth response of Avena sativa in amino-acids-rich soils converted from phenol-contaminated soils by Corynebacterium glutamicum.

    PubMed

    Lee, Soo Youn; Kim, Bit-Na; Choi, Yong Woo; Yoo, Kye Sang; Kim, Yang-Hoon; Min, Jiho

    2012-04-01

    The biodegradation of phenol in laboratory-contaminated soil was investigated using the Gram-positive soil bacterium Corynebacterium glutamicum. This study showed that the phenol degradation caused by C. glutamicum was greatly enhanced by the addition of 1% yeast extract. From the toxicity test using Daphnia magna, the soil did not exhibit any hazardous effects after the phenol was removed using C. glutamicum. Additionally, the treatment of the phenolcontaminated soils with C. glutamicum increased various soil amino acid compositions, such as glycine, threonine, isoleucine, alanine, valine, leucine, tyrosine, and phenylalanine. This phenomenon induced an increase in the seed germination rate and the root elongation of Avena sativa (oat). This probably reflects that increased soil amino acid composition due to C. glutamicum treatment strengthens the plant roots. Therefore, the phenol-contaminated soil was effectively converted through increased soil amino acid composition, and additionally, the phenol in the soil environment was biodegraded by C. glutamicum.

  19. Aldohexuronic Acid Catabolism by a Soil Aeromonas

    PubMed Central

    Farmer, J. J.; Eagon, R. G.

    1969-01-01

    Bacteria which utilize mannuronic acid as an energy source were isolated from nature. One of the organisms, identified as a member of the genus Aeromonas, used glucuronate, galacturonate, and mannuronate as the sole source of carbon and energy. Glucuronate- and galacturonate-grown resting cells oxidized both glucuronate and galacturonate rapidly, but mannuronate slowly. Mannuronate-grown cells oxidized all three rapidly, with the rate of mannuronate utilization somewhat lower. Cell-free extracts from glucuronate-, galacturonate-, and mannuronate-grown Aeromonas C11-2B contained glucuronate and galacturonate isomerases, fructuronate, tagaturonate, and mannuronate reductases, and mannonate and altronate dehydratases, with the exception of glucuronate-grown cells which lacked altronate dehydratase. Thus, the pathway for glucuronate and galacturonate catabolism for Aeromonas was identical to Escherichia coli. Glucuronate and galacturonate were isomerized to d-fructuronate and d-tagaturonate which were then reduced by reduced nicotinamide adenine dinucleotide to d-mannonate and d-altronate, respectively. The hexonic acids were dehydrated to 2-keto-3-deoxy gluconate which was phosphorylated by adenosine triphosphate to 2-keto-3-deoxy-6-phospho gluconate. The latter was then cleaved to pyruvate and glyceraldehyde-3-phosphate. Mannuronate was reduced directly to d-mannonate by a reduced nicotinamide adenine dinucleotide phosphate-linked oxidoreductase. d-Mannonate was then further broken down as in the glucuronate pathway. The mannuronate reducing enzyme, for which the name d-mannonate:nicotinamide adenine dinucleotide (phosphate) oxidoreductase (d-mannuronate-forming) was proposed, was shown to be distinct from altronate and mannoate oxidoreductases. This is the first report of a bacterial oxidoreductase which reduces an aldohexuronic acid to a hexonic acid. The enzyme should prove to be a useful analytical tool for determining mannuronate in the presence of other uronic

  20. Natural acidity of waters in podzolized soils and potential impacts from acid precipitation

    SciTech Connect

    Stednick, J.D.; Johnson, D.W.

    1982-01-01

    Nutrient movements through sites in southeast Alaska and Washington were documented to determine net changes in chemical composition of precipitation water as it passed through a forest soil and became stream flow. These sites were not subject to acid precipitation (rainfall pH 5.8 to 7.2), yet soil water was acidified to 4.2 by natural organic acid forming processes in the podzol soils. Organic acids precipitated in the subsoils, allowing a pH increase. Stream water pH ranged from 6.5 to 7.2 indicating a natural buffering capacity that may exceed any additional acid input from acid rain. Precipitation composition was dominated by magnesium, sodium, and chloride due to the proximity of the ocean at the southeast Alaska site. Anionic constituents of the precipitation were dominated by bicarbonate at the Washington site. Soil podzolization processes concurrently increased solution color and iron concentrations in the litter and surface horizons leachates. The anion flux through the soil profile was dominated by chloride and sulfate at the southwast Alaska site, whereas at the Washington site anion flux appeared to be dominated by organic acids. Electroneutrality calculations indicated a cation deficit for the southeast Alaska site. 10 references, 2 tables.

  1. Natural acidity of waters in podzolized soils and potential impacts from acid precipitation

    SciTech Connect

    Stednick, J.D.; Johnson, D.W.

    1982-01-01

    Nutrient movements through sites in southeast Alaska and Washington were documented to determine net changes in chemical composition of precipitation water as it passed through a forest soil and became stream-flow. These sites were not subject to acid precipitation (rainfall pH 5.8 to 7.2), yet soil water was acidified to 4.2 by natural organic acid-forming processes in the podzol soils. Organic acids precipitated in the subsoils, allowing a pH increase. Streamwater pH ranged from 6.5 to 7.2 indicating a natural buffering capacity that may exceed any additional acid input from acid rain. Precipitation composition was dominated by calcium, magnesium, sodium, and chloride due to the proximity of the ocean at the southeast Alaska site. Anionic constituents of the precipitation were dominated by bicarbonate at the Washington site. Soil podzolization processes concurrently increased solution color and iron concentrations in the litter and surface horizons leachates. The anion flux through the soil profile was dominated by chloride and sulfate at the southeast Alaska site, whereas at the Washington site anion flux appeared to be dominated by organic acids. Electroneutrality calculations indicated a cation deficit for the southeast Alaska site.

  2. Organic amendments increase soil solution phosphate concentrations in an acid soil: A controlled environment study

    SciTech Connect

    Schefe, C.R.; Patti, A.F.; Clune, T.S.; Jackson, R.

    2008-04-15

    Soil acidification affects at least 4 million hectares of agricultural land in Victoria, Australia. Low soil pH can inhibit plant growth through increased soluble aluminum (Al) concentrations and decreased available phosphorus (P). The addition of organic amendments may increase P availability through competition for P binding sites, solubilization of poorly soluble P pools, and increased solution pH. The effect of two organic amendments (lignite and compost) on P solubility in an acid soil was determined through controlled environment (incubation) studies. Three days after the addition of lignite and compost, both treatments increased orthophosphate and total P measured in soil solution, with the compost treatments having the greatest positive effect. Increased incubation time (26 days) increased soil solution P concentrations in both untreated and amended soils, with the greatest effect seen in total P concentrations. The measured differences in solution P concentrations between the lignite- and compost-amended treatments were likely caused by differences in solution chemistry, predominantly solution pH and cation dynamics. Soil amendment with lignite or compost also increased microbial activity in the incubation systems, as measured by carbon dioxide respiration. Based on the results presented, it is proposed that the measured increase in soil solution P with amendment addition was likely caused by both chemical and biological processes, including biotic and abiotic P solubilization reactions, and the formation of soluble organic-metal complexes.

  3. Mechanisms for the retention of inorganic N in acidic forest soils of southern China

    PubMed Central

    Zhang, Jin-bo; Cai, Zu-cong; Zhu, Tong-bin; Yang, Wen-yan; Müller, Christoph

    2013-01-01

    The mechanisms underlying the retention of inorganic N in acidic forest soils in southern China are not well understood. Here, we simultaneously quantified the gross N transformation rates of various subtropical acidic forest soils located in southern China (southern soil) and those of temperate forest soils located in northern China (northern soil). We found that acidic southern soils had significantly higher gross rates of N mineralization and significantly higher turnover rates but a much greater capacity for retaining inorganic N than northern soils. The rates of autotrophic nitrification and NH3 volatilization in acidic southern soils were significantly lower due to low soil pH. Meanwhile, the relatively higher rates of NO3− immobilization into organic N in southern soils can counteract the effects of leaching, runoff, and denitrification. Taken together, these processes are responsible for the N enrichment of the humid subtropical forest soils in southern China. PMID:23907561

  4. Acid soil infertility effects on peanut yields and yield components

    SciTech Connect

    Blamey, F.P.C.

    1983-01-01

    The interpretation of soil amelioration experiments with peanuts is made difficult by the unpredictibility of the crop and by the many factors altered when ameliorating acid soils. The present study was conducted to investigate the effects of lime and gypsum applications on peanut kernel yield via the three first order yield components, pods per ha, kernels per pod, and kernel mass. On an acid medium sandy loam soil (typic Plinthustult), liming resulted in a highly significant kernel yield increase of 117% whereas gypsum applications were of no significant benefit. As indicated by path coefficient analysis, an increase in the number of pods per ha was markedly more important in increasing yield than an increase in either the number of kernels per pod or kernel mass. Furthermore, exch. Al was found to be particularly detrimental to pod number. It was postulated that poor peanut yields resulting from acid soil infertility were mainly due to the depressive effect of exch. Al on pod number. Exch. Ca appeared to play a secondary role by ameliorating the adverse effects of exch. Al.

  5. Sorption of tebuconazole onto selected soil minerals and humic acids.

    PubMed

    Cadková, Eva; Komárek, Michael; Kaliszová, Regina; Koudelková, Věra; Dvořák, Jiří; Vaněk, Aleš

    2012-01-01

    The aim of the present study was to investigate tebuconazole sorption on common soil minerals (birnessite, ferrihydrite, goethite, calcite and illite) and humic acids (representing soil organic matter). Tebuconazole was used (i) in the commercial form Horizon 250 EW and (ii) as an analytical grade pure chemical. In the experiment with the commercially available tebuconazole, a significant pH-dependent sorption onto the oxides was observed (decreasing sorption with increasing pH). The highest sorption was found for ferrihydrite due to its high specific surface area, followed by humic acids, birnessite, goethite and illite. No detectable sorption was found for calcite. The sorption of analytical grade tebuconazole on all selected minerals was significantly lower compared to the commercial product. The sorption was the highest for humic acids, followed by ferrihydrite and illite and almost negligible for goethite and birnessite without any pH dependence. Again, no sorption was observed for calcite. The differences in sorption of the commercially available and analytical grade tebuconazole can be attributed to the additives (e.g., solvents) present in the commercial product. This work proved the importance of soil mineralogy and composition of the commercially available pesticides on the behavior of tebuconazole in soils.

  6. Plant adaptation to acid soils: the molecular basis for crop aluminum resistance

    USDA-ARS?s Scientific Manuscript database

    Aluminum (Al) toxicity on acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world’s potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to ...

  7. Adsorption of glyphosate and aminomethylphosphonic acid in soils

    NASA Astrophysics Data System (ADS)

    Rampazzo, N.; Rampazzo Todorovic, G.; Mentler, A.; Blum, W. E. H.

    2013-03-01

    The results showed that glyphosate is initially adsorbed mostly in the upper 2 cm. It is than transported and adsorbed after few days in deeper soil horizons with concomitant increasing content of its metabolite aminomethylphosphonic acid. Moreover, Fe-oxides seem to be a key parameter for glyphosate and aminomethylphosphonic adsorption in soils. This study confirmed previous studies: the analysis showed lower contents of dithionite-soluble and Fe-oxides for the Chernozem, with consequently lower adsorption of glyphosate and aminomethylphosphonic as compared with the Cambisol and the Stagnosol.

  8. Sulphate removal from sodium sulphate-rich brine and recovery of barium as a barium salt mixture.

    PubMed

    Vadapalli, Viswanath R K; Zvimba, John N; Mulopo, Jean; Motaung, Solly

    2013-01-01

    Sulphate removal from sodium sulphate-rich brine using barium hydroxide and recovery of the barium salts has been investigated. The sodium sulphate-rich brine treated with different dosages of barium hydroxide to precipitate barium sulphate showed sulphate removal from 13.5 g/L to less than 400 mg/L over 60 min using a barium to sulphate molar ratio of 1.1. The thermal conversion of precipitated barium sulphate to barium sulphide achieved a conversion yield of 85% using coal as both a reducing agent and an energy source. The recovery of a pure mixture of barium salts from barium sulphide, which involved dissolution of barium sulphide and reaction with ammonium hydroxide resulted in recovery of a mixture of barium carbonate (62%) and barium hydroxide (38%), which is a critical input raw material for barium salts based acid mine drainage (AMD) desalination technologies. Under alkaline conditions of this barium salt mixture recovery process, ammonia gas is given off, while hydrogen sulfide is retained in solution as bisulfide species, and this provides basis for ammonium hydroxide separation and recovery for reuse, with hydrogen sulfide also recoverable for further industrial applications such as sulfur production by subsequent stripping.

  9. High abundance of Crenarchaeota in a temperate acidic forest soil.

    PubMed

    Kemnitz, Dana; Kolb, Steffen; Conrad, Ralf

    2007-06-01

    The objective of the study was to elucidate the depth distribution and community composition of Archaea in a temperate acidic forest soil. Numbers of Archaea and Bacteria were measured in the upper 18 cm of the soil, and soil cores were sampled on two separate occasions using quantitative PCR targeting 16S rRNA genes. Maximum numbers of Archaea were 0.6-3.8 x 10(8) 16S rRNA genes per gram of dry soil. Numbers of Bacteria were generally higher, but Archaea always accounted for a high percentage of the total gene numbers (12-38%). The archaeal community structure was analysed by the construction of clone libraries and by terminal restriction length polymorphism (T-RFLP) using the same Archaea-specific primers. With the reverse primer labelled, T-RFLP analysis led to the detection of four T-RFs. Three had lengths of 83, 185 and 218 bp and corresponded to uncultured Crenarchaeota. One (447 bp) was assigned to Thermoplasmales. Labelling of the forward primer allowed further separation of the T-RF into Crenarchaeota Group I.1c and Group I.1b, and indicated that Crenarchaeota of the Group I.1c were the predominant 16S rRNA genotype (soil. The abundance of Archaea and concentration of ammonia and nitrate decreased with soil depth. Hence it is unclear if the detected Crenarchaeota Group I.1c participated in ammonia oxidation or had another phenotype.

  10. Citramalic acid and salicylic acid in sugar beet root exudates solubilize soil phosphorus

    PubMed Central

    2011-01-01

    Background In soils with a low phosphorus (P) supply, sugar beet is known to intake more P than other species such as maize, wheat, or groundnut. We hypothesized that organic compounds exuded by sugar beet roots solubilize soil P and that this exudation is stimulated by P starvation. Results Root exudates were collected from plants grown in hydroponics under low- and high-P availability. Exudate components were separated by HPLC, ionized by electrospray, and detected by mass spectrometry in the range of mass-to-charge ratio (m/z) from 100 to 1000. Eight mass spectrometric signals were enhanced at least 5-fold by low P availability at all harvest times. Among these signals, negative ions with an m/z of 137 and 147 were shown to originate from salicylic acid and citramalic acid. The ability of both compounds to mobilize soil P was demonstrated by incubation of pure substances with Oxisol soil fertilized with calcium phosphate. Conclusions Root exudates of sugar beet contain salicylic acid and citramalic acid, the latter of which has rarely been detected in plants so far. Both metabolites solubilize soil P and their exudation by roots is stimulated by P deficiency. These results provide the first assignment of a biological function to citramalic acid of plant origin. PMID:21871058

  11. 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...

  12. Acid sulfate soils are an environmental hazard in Finland

    NASA Astrophysics Data System (ADS)

    Pihlaja, Jouni

    2016-04-01

    Acid sulfate soils (ASS) create significant threats to the environment on coastal regions of the Baltic Sea in Finland. The sediments were deposited during the ancient Litorina Sea phase of the Baltic Sea about 7500-4500 years ago. Finland has larger spatial extent of the ASS than any other European country. Mostly based on anthropogenic reasons (cultivation, trenching etc.) ASS deposits are currently being exposed to oxygen which leads to chemical reaction creating sulfuric acid. The acidic waters then dissolve metals form the soil. Acidic surface run off including the metals are then leached into the water bodies weakening the water quality and killing fish or vegetation. In constructed areas acidic waters may corrode building materials. Geological Survey of Finland (GTK) is mapping ASS deposits in Finland. The goal is to map a total of 5 million hectares of the potentially ASS affected region. It has been estimated that the problematic Litorina Sea deposits, which are situated 0-100 m above the recent Baltic Sea shoreline, cover 500 000 hectares area. There are several phases in mapping. The work begins at the office with gathering the existing data, interpreting airborne geophysical data and compiling a field working plan. In the field, quality of the soil is studied and in uncertain cases samples are taken to laboratory analyses. Also electrical conductivity and pH of soil and water are measured in the field. Laboratory methods include multielemental determinations with ICP-OES, analyses of grain size and humus content (LOI), and incubation. So far, approximately 60 % of the potential ASS affected regions in Finland are mapped. Over 15 000 sites have been studied in the field and 4000 laboratory analyses are done. The spatial database presented in the scale of 1: 250 000 can be viewed at the GTK's web pages (http://gtkdata.gtk.fi/hasu/index.html).

  13. Stable isotope fractionation related to technically enhanced bacterial sulphate degradation in lignite mining sediments.

    PubMed

    Knöller, Kay; Jeschke, Christina; Simon, André; Gast, Martin; Hoth, Nils

    2012-01-01

    A mine dump aquifer in the Lusatian lignite mining district, Germany, is contaminated with acid mine drainage (AMD). The only natural process that can counteract the effects of the contamination is bacterial sulphate reduction. The technical measures chosen to handle the contamination include the injection of glycerol into the aquifer to supply electron donors and to accelerate the growth and activity of sulphate-reducing bacteria. An initial assessment of the hydrochemical conditions in the aquifer showed that sulphate concentrations are subject to alteration due to flow-related processes. Consequently, the decision whether sulphate reduction is occurring in the investigated aquifer section was based on the stable isotopic composition of dissolved sulphate and sulphide, which were used in combination with sulphate concentrations. The significant enrichment of both heavy sulphur and heavy oxygen in the remaining sulphate pool and a characteristic isotope fractionation pattern are a clear evidence for the activity of sulphate-reducing bacteria utilising the injected glycerol as an electron donor. This activity seemed to intensify over the observation period. The spatial distribution of sulphate reduction activity, however, appeared to be highly inhomogeneous. Rather than occurring ubiquitously, sulphate reduction activity seemed to concentrate in a defined reaction zone. Regardless of the inhomogeneous distribution, the overall turnover of sulphate during the period of investigation proves the applicability of this enhanced natural attenuation method to handle the restoration of aquifers contaminated with AMD.

  14. Sulphate-climate coupling over the past 300,000 years in inland Antarctica.

    PubMed

    Iizuka, Yoshinori; Uemura, Ryu; Motoyama, Hideaki; Suzuki, Toshitaka; Miyake, Takayuki; Hirabayashi, Motohiro; Hondoh, Takeo

    2012-10-04

    Sulphate aerosols, particularly micrometre-sized particles of sulphate salt and sulphate-adhered dust, can act as cloud condensation nuclei, leading to increased solar scattering that cools Earth's climate. Evidence for such a coupling may lie in the sulphate record from polar ice cores, but previous analyses of melted ice-core samples have provided only sulphate ion concentrations, which may be due to sulphuric acid. Here we present profiles of sulphate salt and sulphate-adhered dust fluxes over the past 300,000 years from the Dome Fuji ice core in inland Antarctica. Our results show a nearly constant flux of sulphate-adhered dust through glacial and interglacial periods despite the large increases in total dust flux during glacial maxima. The sulphate salt flux, however, correlates inversely with temperature, suggesting a climatic coupling between particulate sulphur and temperature. For example, the total sulphate salt flux during the Last Glacial Maximum averages 5.78 mg m(-2) yr(-1), which is almost twice the Holocene value. Although it is based on a modern analogue with considerable uncertainties when applied to the ice-core record, this analysis indicates that the glacial-to-interglacial decrease in sulphate would lessen the aerosol indirect effects on cloud lifetime and albedo, leading to an Antarctic warming of 0.1 to 5 kelvin.

  15. Simple method of isolating humic acids from organic soils

    NASA Astrophysics Data System (ADS)

    Ahmed, O.

    2009-04-01

    Humic substances particularly humic acids (HA) play a major role in soil conditioning e.g. erosion control, soil cation exchange capacity, complexation of heavy metal ions and pesticides, carbon and nitrogen cycles, plant growth and reduction of ammonia volatilization from urea. Humified substances such as coal, composts, and peat soils have substantial amounts of HA but the isolation of these acids is expensive, laborious, and time consuming. Factors that affect the quality and yield of HA isolated from these materials include extraction, fractionation, and purification periods. This work developed a simple, rapid, and cost effective method of isolating HA from peat soils. There was a quadratic relationship between extraction period and HA yield. Optimum extraction period was estimated at 4 h instead of the usual range of 12 to 48 h. There was no relationship between fractionation period and HA yield. As such 2 h instead of the usual range of 12 to 24 h fractionation period could be considered optimum. Low ash content (5%), remarkable reduction in K, coupled with the fact that organic C, E4/E6, carboxylic COOH, phenolic OH, and total acidity values of the HA were consistent with those reported by other authors suggest that the HA dealt with were free from mineral matter. This was possible because the distilled water used to purify the HA served as Bronsted-Lowry acid during the purification process of the HA. Optimum purification period using distilled waster was 1 h instead of the usual range of 1 and 7 days (uses HF and HCl and dialysis). Humic acids could be isolated from tropical peat soils within 7 h (i.e. 4 h extraction, 2 h fractionation, and 1 h purification) instead of the existing period of 2 and 7 days. This could facilitate the idea of producing organic fertilizers such as ammonium-humate and potassium-humate from humified substances since techniques devised in this study did not alter the true nature of the HA. Besides, the technique is rapid, simple

  16. Simple method of isolating humic acids from organic soils

    NASA Astrophysics Data System (ADS)

    Ahmed, O. H.; Susilawati, K.; Nik Muhamad, A. B.; Khanif, M. Y.

    2009-04-01

    Humic substances particularly humic acids (HA) play a major role in soil conditioning e.g. erosion control, soil cation exchange capacity, complexation of heavy metal ions and pesticides, carbon and nitrogen cycles, plant growth and reduction of ammonia volatilization from urea. Humified substances such as coal, composts, and peat soils have substantial amounts of HA but the isolation of these acids is expensive, laborious, and time consuming. Factors that affect the quality and yield of HA isolated from these materials include extraction, fractionation, and purification periods. This work developed a simple, rapid, and cost effective method of isolating HA from peat soils. There was a quadratic relationship between extraction period and HA yield. Optimum extraction period was estimated at 4 h instead of the usual range of 12 to 48 h. There was no relationship between fractionation period and HA yield. As such 2 h instead of the usual range of 12 to 24 h fractionation period could be considered optimum. Low ash content (5%), remarkable reduction in K, coupled with the fact that organic C, E4/E6, carboxylic COOH, phenolic OH, and total acidity values of the HA were consistent with those reported by other authors suggest that the HA dealt with were free from mineral matter. This was possible because the distilled water used to purify the HA served as Bronsted-Lowry acid during the purification process of the HA. Optimum purification period using distilled waster was 1 h instead of the usual range of 1 and 7 days (uses HF and HCl and dialysis). Humic acids could be isolated from tropical peat soils within 7 h (i.e. 4 h extraction, 2 h fractionation, and 1 h purification) instead of the existing period of 2 and 7 days. This could facilitate the idea of producing organic fertilizers such as ammonium-humate and potassium-humate from humified substances since techniques devised in this study did not alter the true nature of the HA. Besides, the technique is rapid, simple

  17. Soil surface acidity plays a determining role in the atmospheric-terrestrial exchange of nitrous acid

    PubMed Central

    Donaldson, Melissa A.; Bish, David L.; Raff, Jonathan D.

    2014-01-01

    Nitrous acid (HONO) is an important hydroxyl (OH) radical source that is formed on both ground and aerosol surfaces in the well-mixed boundary layer. Recent studies report the release of HONO from nonacidic soils, although it is unclear how soil that is more basic than the pKa of HONO (∼3) is capable of protonating soil nitrite to serve as an atmospheric HONO source. Here, we used a coated-wall flow tube and chemical ionization mass spectrometry (CIMS) to study the pH dependence of HONO uptake onto agricultural soil and model substrates under atmospherically relevant conditions (1 atm and 30% relative humidity). Experiments measuring the evolution of HONO from pH-adjusted surfaces treated with nitrite and potentiometric titrations of the substrates show, to our knowledge for the first time, that surface acidity rather than bulk aqueous pH determines HONO uptake and desorption efficiency on soil, in a process controlled by amphoteric aluminum and iron (hydr)oxides present. The results have important implications for predicting when soil nitrite, whether microbially derived or atmospherically deposited, will act as a net source or sink of atmospheric HONO. This process represents an unrecognized mechanism of HONO release from soil that will contribute to HONO emissions throughout the day. PMID:25512517

  18. Soil surface acidity plays a determining role in the atmospheric-terrestrial exchange of nitrous acid.

    PubMed

    Donaldson, Melissa A; Bish, David L; Raff, Jonathan D

    2014-12-30

    Nitrous acid (HONO) is an important hydroxyl (OH) radical source that is formed on both ground and aerosol surfaces in the well-mixed boundary layer. Recent studies report the release of HONO from nonacidic soils, although it is unclear how soil that is more basic than the pKa of HONO (∼ 3) is capable of protonating soil nitrite to serve as an atmospheric HONO source. Here, we used a coated-wall flow tube and chemical ionization mass spectrometry (CIMS) to study the pH dependence of HONO uptake onto agricultural soil and model substrates under atmospherically relevant conditions (1 atm and 30% relative humidity). Experiments measuring the evolution of HONO from pH-adjusted surfaces treated with nitrite and potentiometric titrations of the substrates show, to our knowledge for the first time, that surface acidity rather than bulk aqueous pH determines HONO uptake and desorption efficiency on soil, in a process controlled by amphoteric aluminum and iron (hydr)oxides present. The results have important implications for predicting when soil nitrite, whether microbially derived or atmospherically deposited, will act as a net source or sink of atmospheric HONO. This process represents an unrecognized mechanism of HONO release from soil that will contribute to HONO emissions throughout the day.

  19. Study of protein-probe interaction and protective action of surfactant sodium dodecyl sulphate in urea-denatured HSA using charge transfer fluorescence probe methyl ester of N,N-dimethylamino naphthyl acrylic acid.

    PubMed

    Mahanta, Subrata; Singh, Rupashree Balia; Guchhait, Nikhil

    2009-03-01

    We have demonstrated that the intramolecular charge transfer (ICT) probe Methyl ester of N,N-dimethylamino naphthyl acrylic acid (MDMANA) serves as an efficient reporter of the proteinous microenvironment of Human Serum Albumin (HSA). This work reports the binding phenomenon of MDMANA with HSA and spectral modulation thereupon. The extent of binding and free energy change for complexation reaction along with efficient fluorescence resonance energy transfer from Trp-214 of HSA to MDMANA indicates strong binding between probe and protein. Fluorescence anisotropy, red edge excitation shift, acrylamide quenching and time resolved measurements corroborate the binding nature of the probe with protein and predicts that the probe molecule is located at the hydrophobic site of the protein HSA. Due to the strong binding ability of MDMANA with HSA, it is successfully utilized for the study of stabilizing action of anionic surfactant Sodium Dodecyl Sulphate to the unfolding and folding of protein with denaturant urea in concentration range 1M to 9M.

  20. Analytical applications of condensed phosphoric acid-IV Iodometric determination of sulphur in sulphate and sulphide ores and minerals and other compounds after reduction with sodium hypophosphite and tin metal in condensed phosphoric acid.

    PubMed

    Mizoguchi, T; Ishii, H

    1980-06-01

    Sulphate in sulphate ores, e.g., alunite, anglesite, barytes, chalcanthite, gypsum, manganese sulphate ore, is reduced to hydrogen sulphide by the hypophosphite-tin metal-CPA method, if a slight modification is made. Sulphide ores, e.g., galena, sphalerite, are quantitatively decomposed with CPA alone to give hydrogen sulphide. Suitable reducing agents must be used for the quantitative recovery of hydrogen sulphide from pyrite, nickel sulphide, cobalt sulphide and cadmium sulphide, or elemental sulphur is liberated. Iodide must be used in the decomposition of chalcopyrite; the copper sulphide is too stable to be decomposed by CPA alone. Molybdenite is not decomposed in CPA even if reducing agents are added. The pretreatment methods for the determination of sulphur in sulphur oxyacids and elemental sulphur have also been investigated.

  1. Acid precipitation and ionic movements in Adironack forest soils

    SciTech Connect

    Mollitor, A.V.; Raynal, D.J.

    1982-01-01

    To examine potential effects of acid precipitation on forest soils in a hardwood and in a coniferous stand in the central Adirondacks of New York State, solution chemistry was studied in five strata of these ecosystems. Bulk precipitation, throughfall, and soil leachates were sampled and analyzed for pH, NO/sub 3/, SO/sub 4/, K, Ca, Mg, and Na. A subset of the samples were analyzed for Al. Organic anion concentrations were estimated from ionic charge balances. Concentrations of NO/sub 3/, H, and K in B horizon leachates were not significantly different than precipitation concentrations, while concentrations of SO/sub 4/, Ca, Mg, and Na in water leaving the sola were significantly greater than precipitation concentrations. Patterns of movement for most ions were similar for both study sites, but concentrations were generally greater in the conifer system. Cation leaching from the hardwood site appears about equally influenced by SO/sub 4/ and organic anion leaching. Sulfate and organic anion concentrations were greater in the conifer site but organic anion leaching dominated. Sulfate appears highly mobile in these soils. Chronic leaching by H/sub 2/SO/sub 4/ combined with internally generated organic acids may represent a threat to the nutrient status of many Adirondack forest soils.

  2. Soil peroxidase-mediated chlorination of fulvic acid

    NASA Astrophysics Data System (ADS)

    Asplund, Gunilla; Borén, Hans; Carlsson, Uno; Grimvall, Anders

    Humic matter has recently been shown to contain considerable quantities of naturally produced organohalogens. The present study investigated the possibility of a non-specific, enzymatically mediated halogenation of organic matter in soil. The results showed that, in the presence of chloride and hydrogen peroxide, the enzyme chloroperoxidase (CPO) from the fungus Caldariomyces fumago catalyzes chlorination of fulvic acid. At pH 2.5 - 6.0, the chlorine to fulvic acid ratio in the tested sample was elevated from 12 mg/g to approximately 40-50 mg/g. It was also shown that this reaction can take place at chloride and hydrogen peroxide concentrations found in the environment. An extract from spruce forest soil was shown to have a measurable chlorinating capacity. The activity of an extract of 0.5 kg soil corresponded to approximately 0.3 enzyme units, measured as CPO activity. Enzymatically mediated halogenation of humic substances may be one of the mechanisms explaining the widespread occurrence of adsorbable organic halogens (AOX) in soil and water.

  3. Extraction and Analysis of Microbial Phospholipid Fatty Acids in Soils

    PubMed Central

    Quideau, Sylvie A.; McIntosh, Anne C.S.; Norris, Charlotte E.; Lloret, Emily; Swallow, Mathew J.B.; Hannam, Kirsten

    2016-01-01

    Phospholipid fatty acids (PLFAs) are key components of microbial cell membranes. The analysis of PLFAs extracted from soils can provide information about the overall structure of terrestrial microbial communities. PLFA profiling has been extensively used in a range of ecosystems as a biological index of overall soil quality, and as a quantitative indicator of soil response to land management and other environmental stressors. The standard method presented here outlines four key steps: 1. lipid extraction from soil samples with a single-phase chloroform mixture, 2. fractionation using solid phase extraction columns to isolate phospholipids from other extracted lipids, 3. methanolysis of phospholipids to produce fatty acid methyl esters (FAMEs), and 4. FAME analysis by capillary gas chromatography using a flame ionization detector (GC-FID). Two standards are used, including 1,2-dinonadecanoyl-sn-glycero-3-phosphocholine (PC(19:0/19:0)) to assess the overall recovery of the extraction method, and methyl decanoate (MeC10:0) as an internal standard (ISTD) for the GC analysis. PMID:27685177

  4. A conceptual framework: redifining forests soil's critical acid loads under a changing climate

    Treesearch

    Steven G. McNulty; Johnny L. Boggs

    2010-01-01

    Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it...

  5. Acid washing and stabilization of an artificial arsenic-contaminated soil.

    PubMed

    Tokunaga, Shuzo; Hakuta, Toshikatsu

    2002-01-01

    An acid-washing process was studied on a laboratory scale to extract the bulk of arsenic(V) from a highly contaminated Kuroboku soil (Andosol) so as to minimize the risk of arsenic to human health and the environment. The sorption and desorption behavior of arsenic in the soil suggested the possibility of arsenic leaching under acidic conditions. Artificially contaminated Kuroboku soil (2830 mg As/kg soil) was washed with different concentrations of hydrogen fluoride, phosphoric acid, sulfuric acid, hydrogen chloride, nitric acid, perchloric acid, hydrogen bromide, acetic acid, hydrogen peroxide, 3:1 hydrogen chloride-nitric acid, or 2:1 nitric acid-perchloric acid. Phosphoric acid proved to be most promising as an extractant, attaining 99.9% arsenic extraction at 9.4% acid concentration in 6 h. Sulfuric acid also attained high percentage extraction. The arsenic extraction by these acids reached equilibrium within 2 h. Elovich-type equation best described most of the kinetic data for dissolution of soil components as well as for extraction of arsenic. Dissolution of the soil components could be minimized by ceasing acid washing in 2 h. The acid-washed soil was further stabilized by the addition of lanthanum, cerium, and iron(III) salts or their oxides or hydroxides which form insoluble complex with arsenic. Both salts and oxides of lanthanum and cerium were effective in immobilizing arsenic in the soil attaining less than 0.01 mg/l As in the leaching test.

  6. Reclamation of acid sulfate soils using lime-stabilized biosolids.

    PubMed

    Orndorff, Zenah W; Daniels, W Lee; Fanning, Delvin S

    2008-01-01

    Excavation of sulfidic materials during construction has resulted in acid rock drainage (ARD) problems throughout Virginia. The most extensive documented uncontrolled disturbance at a single location is Stafford Regional Airport (SRAP) in Stafford, Virginia. Beginning in 1998, over 150 ha of sulfidic Coastal Plain sediments were disturbed, including steeply sloping cut surfaces and spoils placed into fills. Acid sulfate soils developed, and ARD generated on-site degraded metal and concrete structures and heavily damaged water quality with effects noted over 1 km downstream. The site was not recognized as sulfidic until 2001 when surface soil sampling revealed pH values ranging from 1.9 to 5.3 and peroxide potential acidity (PPA) values ranging from 1 to 42 Mg CaCO(3) per 1000 Mg material. In February 2002 a water quality program was established in and around the site to monitor baseline pH, EC, NO(3)-N, NH(4)-N, PO(4)-P, Fe, Al, Mn, and SO(4)-S, and initial pH values as low as 2.9 were noted in on-site receiving streams. In the spring and fall of 2002, the site was treated with variable rates of lime-stabilized biosolids, straw-mulch, and acid- and salt-tolerant legumes and grasses. By October 2002, the site was fully revegetated (> or = 90% living cover) with the exception of a few highly acidic outcrops and seepage areas. Surface soil sampling in 2003, 2004, and 2006 revealed pH values typically > 6.0. Water quality responded quickly to treatment, although short-term NH(4)(+) release occurred. Despite heavy loadings, no significant surface water P losses were observed.

  7. Interactive effects of soil acidity and fluoride on soil solution aluminium chemistry and barley (Hordeum vulgare L.) root growth.

    PubMed

    Manoharan, V; Loganathan, P; Tillman, R W; Parfitt, R L

    2007-02-01

    A greenhouse study was conducted to determine if concentrations of fluoride (F), which would be added to acid soils via P fertilisers, were detrimental to barley root growth. Increasing rates of F additions to soil significantly increased the soil solution concentrations of aluminium (Al) and F irrespective of the initial adjusted soil pH, which ranged from 4.25 to 5.48. High rates of F addition severely restricted root growth; the effect was more pronounced in the strongly acidic soil. Speciation calculations demonstrated that increasing rates of F additions substantially increased the concentrations of Al-F complexes in the soil. Stepwise regression analysis showed that it was the combination of the activities of AlF2(1+) and AlF(2+) complexes that primarily controlled barley root growth. The results suggested that continuous input of F to soils, and increased soil acidification, may become an F risk issue in the future.

  8. Relationships between soil properties and community structure of soil macroinvertebrates in oak-history forests along an acidic deposition gradient

    SciTech Connect

    Kuperman, R.G.

    1996-02-01

    Soil macroinvertebrate communities were studied in ecologically analogous oak-hickory forests across a three-state atmospheric pollution gradient in Illinois, Indiana, and Ohio. The goal was to investigate changes in the community structure of soil fauna in study sites receiving different amounts of acidic deposition for several decades and the possible relationships between these changes and physico-chemical properties of soil. The study revealed significant differences in the numbers of soil animals among the three study sites. The sharply differentiated pattern of soil macroinvertebrate fauna seems closely linked to soil chemistry. Significant correlations of the abundance of soil macroinvertebrates with soil parameters suggest that their populations could have been affected by acidic deposition in the region. Abundance of total soil macroinvertebrates decreased with the increased cumulative loading of acidic deposition. Among the groups most sensitive to deposition were: earthworms gastropods, dipteran larvae, termites, and predatory beetles. The results of the study support the hypothesis that chronic long-term acidic deposition could aversely affect the soil decomposer community which could cause lower organic matter turnover rates leading to an increase in soil organic matter content in high deposition sites.

  9. Enzymatically- and Ultraviolet-labile Phosphorus in Humic Acid Fractions From Rice Soils

    USDA-ARS?s Scientific Manuscript database

    Humic acid is an important soil component which can improve nutrient availability and impact other important chemical, biological, and physical properties of soils. We investigated the lability of phosphorus (P) in the mobile humic acid (MHA) and calcium humate (CaHA) fractions of four rice soils as...

  10. [Characteristics of soil pH and exchangeable acidity in red soil profile under different vegetation types].

    PubMed

    Ji, Gang; Xu, Ming-gang; Wen, Shi-lin; Wang, Bo-ren; Zhang, Lu; Liu, Li-sheng

    2015-09-01

    The characteristics of soil pH and exchangeable acidity in soil profile under different vegetation types were studied in hilly red soil regions of southern Hunan Province, China. The soil samples from red soil profiles within 0-100 cm depth at fertilized plots and unfertilized plots were collected and analyzed to understand the profile distribution of soil pH and exchangeable acidity. The results showed that, pH in 0-60 cm soil from the fertilized plots decreased as the following sequence: citrus orchard > Arachis hypogaea field > tea garden. As for exchangeable acidity content, the sequence was A. hypogaea field ≤ citrus orchard < tea garden. After tea tree and A. hypogaea were planted for long time, acidification occurred in surface soil (0-40 cm), compared with the deep soil (60-100 cm), and soil pH decreased by 0.55 and 0.17 respectively, but such changes did not occur in citrus orchard. Soil pH in 0-40 cm soil from the natural recovery vegetation unfertilized plots decreased as the following sequence: Imperata cylindrica land > Castanea mollissima garden > Pinus elliottii forest ≥ Loropetalum chinensis forest. As for exchangeable acidity content, the sequence was L cylindrica land < C. mollissima garden < L. chinensis forest ≤ P. elliottii forest. Soil pH in surface soil (0-20 cm) from natural forest plots, secondary forest and Camellia oleifera forest were significantly lower than that from P. massoniana forest, decreased by 0.34 and 0.20 respectively. For exchangeable acidity content in 0-20 cm soil from natural forest plot, P. massoniana forest and secondary forest were significantly lower than C. oleifera forest. Compared with bare land, surface soil acidification in unfertilized plots except I. cylindrica land had been accelerated, and the natural secondary forest was the most serious among them, with surface soil pH decreasing by 0.52. However, the pH increased in deep soils from unfertilized plots except natural secondary forest, and I. cylindrica

  11. Elevational Variation in Soil Amino Acid and Inorganic Nitrogen Concentrations in Taibai Mountain, China

    PubMed Central

    Yang, Xin; Zhu, Lianfeng; Zhang, Junhua; Jin, Qianyu; Wu, Lianghuan

    2016-01-01

    Amino acids are important sources of soil organic nitrogen (N), which is essential for plant nutrition, but detailed information about which amino acids predominant and whether amino acid composition varies with elevation is lacking. In this study, we hypothesized that the concentrations of amino acids in soil would increase and their composition would vary along the elevational gradient of Taibai Mountain, as plant-derived organic matter accumulated and N mineralization and microbial immobilization of amino acids slowed with reduced soil temperature. Results showed that the concentrations of soil extractable total N, extractable organic N and amino acids significantly increased with elevation due to the accumulation of soil organic matter and the greater N content. Soil extractable organic N concentration was significantly greater than that of the extractable inorganic N (NO3−-N + NH4+-N). On average, soil adsorbed amino acid concentration was approximately 5-fold greater than that of the free amino acids, which indicates that adsorbed amino acids extracted with the strong salt solution likely represent a potential source for the replenishment of free amino acids. We found no appreciable evidence to suggest that amino acids with simple molecular structure were dominant at low elevations, whereas amino acids with high molecular weight and complex aromatic structure dominated the high elevations. Across the elevational gradient, the amino acid pool was dominated by alanine, aspartic acid, glycine, glutamic acid, histidine, serine and threonine. These seven amino acids accounted for approximately 68.9% of the total hydrolyzable amino acid pool. The proportions of isoleucine, tyrosine and methionine varied with elevation, while soil major amino acid composition (including alanine, arginine, aspartic acid, glycine, histidine, leucine, phenylalanine, serine, threonine and valine) did not vary appreciably with elevation (p>0.10). The compositional similarity of many

  12. Elevational Variation in Soil Amino Acid and Inorganic Nitrogen Concentrations in Taibai Mountain, China.

    PubMed

    Cao, Xiaochuang; Ma, Qingxu; Zhong, Chu; Yang, Xin; Zhu, Lianfeng; Zhang, Junhua; Jin, Qianyu; Wu, Lianghuan

    2016-01-01

    Amino acids are important sources of soil organic nitrogen (N), which is essential for plant nutrition, but detailed information about which amino acids predominant and whether amino acid composition varies with elevation is lacking. In this study, we hypothesized that the concentrations of amino acids in soil would increase and their composition would vary along the elevational gradient of Taibai Mountain, as plant-derived organic matter accumulated and N mineralization and microbial immobilization of amino acids slowed with reduced soil temperature. Results showed that the concentrations of soil extractable total N, extractable organic N and amino acids significantly increased with elevation due to the accumulation of soil organic matter and the greater N content. Soil extractable organic N concentration was significantly greater than that of the extractable inorganic N (NO3--N + NH4+-N). On average, soil adsorbed amino acid concentration was approximately 5-fold greater than that of the free amino acids, which indicates that adsorbed amino acids extracted with the strong salt solution likely represent a potential source for the replenishment of free amino acids. We found no appreciable evidence to suggest that amino acids with simple molecular structure were dominant at low elevations, whereas amino acids with high molecular weight and complex aromatic structure dominated the high elevations. Across the elevational gradient, the amino acid pool was dominated by alanine, aspartic acid, glycine, glutamic acid, histidine, serine and threonine. These seven amino acids accounted for approximately 68.9% of the total hydrolyzable amino acid pool. The proportions of isoleucine, tyrosine and methionine varied with elevation, while soil major amino acid composition (including alanine, arginine, aspartic acid, glycine, histidine, leucine, phenylalanine, serine, threonine and valine) did not vary appreciably with elevation (p>0.10). The compositional similarity of many

  13. [Effect of low molecular weight organic acids on inorganic phosphorus transformation in red soil and its acidity].

    PubMed

    Hu, Hongqing; Liao, Lixia; Wang, Xinglin

    2002-07-01

    Red soil samples collected from southern Hubei province and northern Jiangxi province were tested to analyze their inorganic phosphorus fractions, pH and active aluminum after incubated with added various organic acids. The results indicated that application of organic acids increased the content of Ca2-P in both red soils, in the order of citric acid > malic acid > succinic acid > acetic acid, did not affect the contents of Ca8-P and Ca10-P, but usually reduced Fe-P, Al-P and O-P. The pH values of the soils treated by organic acids, except for acetic acid, were reduced by 0.65-1.96, compared with the control. Soil active Al extracted with 0.02 mol.L-1 CaCl2 in treatments with citric, malic and succinic acid was 5.7-51.3 times as the control, and Al extracted with 1 mol.L-1 KCl also increased 4.0-67.3 times. However, acetic acid had little influence on active soil Al. It was concluded that in red soils, organic acid could improve phosphorus availability, but enhance the soil toxicity caused by active Al.

  14. Breast cyst fluid heparan sulphate is distinctively N-sulphated depending on apocrine or flattened type.

    PubMed

    Mannello, Ferdinando; Maccari, Francesca; Ligi, Daniela; Santi, Martina; Gatto, Francesco; Linhardt, Robert J; Galeotti, Fabio; Volpi, Nicola

    2015-04-01

    Breast cyst fluid (BCF) contained in gross cists is involved with its many biomolecules in different stages of breast cystic development. Type I apocrine and type II flattened cysts are classified based on biochemical, morphological and hormonal differences, and their different patterns of growth factors and active biocompounds may require different regulation. In a previous paper, hyaluronic acid in a very low content and chondroitin sulphate/dermatan sulphate were identified and characterized in BCF. In this new study, various apocrine and flattened BCFs were analyzed for HS concentration and disaccharide pattern. Apocrine HS was found specifically constituted of N-acetyl groups contrary to flattened HS richer in N-sulphate disaccharides with an overall N-acetylated/N-sulphated ratio significantly increased in apocrine compared with flattened (13.5 vs 3.7). Related to this different structural features, the charge density significantly decreased (~-30%) in apocrine versus flattened BCFs. Finally, no significant differences were observed for HS amount (~0.9-1.3 µg ml(-1) ) between the two BCF types even if a greater content was determined for flattened samples. The specifically N-sulphated sequences in flattened BCF HS can exert biologic capacity by regulating growth factors activity. On the other hand, we cannot exclude a peculiar regulation of the activity of biomolecules in apocrine BCF by HS richer in N-acetylated disaccharides. In fact, the different patterns of growth factors and active biocompounds in the two types of cysts may require different regulation by specific sequences in the HS backbone possessing specific structural characteristics and distinctive chemical groups.

  15. Influence of ameliorating soil acidity with dolomite on the priming of soil C content and CO2 emission.

    PubMed

    Shaaban, Muhammad; Wu, Lei; Peng, Qi-An; van Zwieten, Lukas; Chhajro, Muhammad Afzal; Wu, Yupeng; Lin, Shan; Ahmed, Muhammad Mahmood; Khalid, Muhammad Salman; Abid, Muhammad; Hu, Ronggui

    2017-02-21

    Lime or dolomite is commonly implemented to ameliorate soil acidity. However, the impact of dolomite on CO2 emissions from acidic soils is largely unknown. A 53-day laboratory study was carried out to investigate CO2 emissions by applying dolomite to an acidic Acrisol (rice-rapeseed rotation [RR soil]) and a Ferralsol (rice-fallow/flooded rotation [RF soil]). Dolomite was dosed at 0, 0.5, and 1.5 g 100 g(-1) soil, herein referred to as CK, L, and H, respectively. The soil pH(H2O) increased from 5.25 to 7.03 and 7.62 in L and H treatments of the RR soil and from 5.52 to 7.27 and 7.77 in L and H treatments of the RF soil, respectively. Dolomite application significantly (p ≤ 0.001) increased CO2 emissions in both RR and RF soils, with higher emissions in H as compared to L dose of dolomite. The cumulative CO2 emissions with H dose of dolomite were greater 136% in the RR soil and 149% in the RF soil as compared to CK, respectively. Dissolved organic carbon (DOC) and microbial biomass carbon (MBC) increased and reached at 193 and 431 mg kg(-1) in the RR soil and 244 and 481 mg kg(-1) in the RF soil by H treatments. The NH4(-)-N and NO3(-)-N were also increased by dolomite application. The increase in C and N contents stimulated microbial activities and therefore higher respiration in dolomite-treated soil as compared to untreated. The results suggest that CO2 release in dolomite-treated soils was due to the priming of soil C content rather than chemical reactions.

  16. [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.

  17. EDTA and HCl leaching of calcareous and acidic soils polluted with potentially toxic metals: remediation efficiency and soil impact.

    PubMed

    Udovic, Metka; Lestan, Domen

    2012-07-01

    The environmental risk of potentially toxic metals (PTMs) in soil can be diminished by their removal. Among the available remediation techniques, soil leaching with various solutions is one of the most effective but data about the impact on soil chemical and biological properties are still scarce. We studied the effect of two common leaching agents, hydrochloric acid (HCl) and a chelating agent (EDTA) on Pb, Zn, Cd removal and accessibility and on physico-chemical and biological properties in one calcareous, pH neutral soil and one non-calcareous acidic soil. EDTA was a more efficient leachant compared to HCl: up to 133-times lower chelant concentration was needed for the same percentage (35%) of Pb removal. EDTA and HCl concentrations with similar PTM removal efficiency decreased PTM accessibility in both soils but had different impacts on soil properties. As expected, HCl significantly dissolved carbonates from calcareous soil, while EDTA leaching increased the pH of the acidic soil. Enzyme activity assays showed that leaching with HCl had a distinctly negative impact on soil microbial and enzyme activity, while leaching with EDTA had less impact. Our results emphasize the importance of considering the ecological impact of remediation processes on soil in addition to the capacity for PTM removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Effects of long-term soil amendment with sewage sludges on soil humic acid thermal and molecular properties.

    PubMed

    Fernández, José M; Hockaday, William C; Plaza, César; Polo, Alfredo; Hatcher, Patrick G

    2008-12-01

    Sewage sludges are frequently used as soil amendments due to their high contents of organic matter and nutrients, particularly N and P. However, their effects upon the chemistry of soil humic acids, one of the main components of the soil organic matter, need to be more deeply studied in order to understand the relation between organic matter structure and beneficial soil properties. Two sewage sludges subjected to different types of pre-treatment (composted and thermally dried) with very different chemical compositions were applied for three consecutive years to an agricultural soil under long-term field study. Thermal analysis (TG-DTG-DTA) and solid-state (13)C NMR spectroscopy were used to compare molecular and structural properties of humic acids isolated from sewage sludges, and to determine changes in amended soils. Thermally dried sewage sludge humic acids showed an important presence of alkyl and O/N-alkyl compounds (70%) while composted sludge humic acids comprised 50% aromatic and carbonyl carbon. In spite of important differences in the initial chemical and thermal properties of the two types of sewage sludges, the chemical and thermal properties of the soil humic acids were quite similar to one another after 3 years of amendment. Long-term application of both sewage sludges resulted in 80-90% enrichment in alkyl carbon and organic nitrogen contents of the soil humic acid fraction.

  19. Effect of Short-Chain Fatty Acids and Soil Atmosphere on Tylenchorhynchus spp.

    PubMed Central

    McElderry, Claire F.; Browning, Marsha; Amador, José A.

    2005-01-01

    Short-chain fatty acids can be produced under anaerobic conditions by fermentative soil microbes and have nematicidal properties. We evaluated the effects of butyric and propionic acids on death and recovery of stunt nematodes (Tylenchorhynchus spp.), a common parasite of turfgrass. Nematodes in a sand-soil mix (80:20) were treated with butyric or propionic acid and incubated under air or N₂ for 7 days at 25 °C. Amendment of soil with 0.1 and 1.0 µmol (8.8 and 88 µg) butyric acid/g soil or 1.0 µmol (74 µg) propionic acid/g soil resulted in the death of all nematodes. The composition of the soil atmosphere had no effect on the nematicidal activity of the acids. Addition of hydrochloric acid to adjust soil pH to 4.4 and 3.5 resulted in nematode mortality relative to controls (41% to 86%) but to a lesser degree than short-chain fatty acids at the same pH. Nematodes did not recover after a 28-day period following addition of 10 µmol butyric acid/g soil under air or N₂. Carbon mineralization decreased during this period, whereas levels of inorganic N and microbial biomass-N remained constant. Short-chain fatty acids appear to be effective in killing Tylenchorhynchus spp. independent of atmospheric composition. Nematode mortality appears to be a function of the type and concentration of fatty acid and soil pH. PMID:19262845

  20. Transport of two naphthoic acids and salicylic acid in soil: experimental study and empirical modeling.

    PubMed

    Hanna, K; Lassabatere, L; Bechet, B

    2012-09-15

    In contrast to the parent compounds, the mechanisms responsible for the transport of natural metabolites of polycyclic aromatic hydrocarbons (PAH) in contaminated soils have been scarcely investigated. In this study, the sorption of three aromatic acids (1-naphthoic acid (NA), 1-hydroxy-2-naphthoic acid (HNA) and salicylic acid (SA)) was examined on soil, in a batch equilibrium single-system, with varying pH and acid concentrations. Continuous flow experiments were also carried out under steady-state water flow. The adsorption behavior of naphthoic and benzoic acids was affected by ligand functionality and molecular structure. All modeling options (equilibrium, chemical nonequilibrium, i.e. chemical kinetics, physical nonequilibrium, i.e. surface sites in the immobile water fraction, and both chemical and physical nonequilibrium) were tested in order to describe the breakthrough behavior of organic compounds in homogeneously packed soil columns. Tracer experiments showed a small fractionation of flow into mobile and immobile compartments, and the related hydrodynamic parameters were used for the modeling of reactive transport. In all cases, the isotherm parameters obtained from column tests differed from those derived from the batch experiments. The best accurate modeling was obtained considering nonequilibrium for the three organic compounds. Both chemical and physical nonequilibrium led to appropriate modeling for HNA and NA, while chemical nonequilibrium was the sole option for SA. SA sorption occurs mainly in mobile water and results from the concomitancy of instantaneous and kinetically limited sites. For all organic compounds, retention is contact condition dependent and differs between batch and column experiments. Such results show that preponderant mechanisms are solute dependent and kinetically limited, which has important implications for the fate and transport of carboxylated aromatic compounds in contaminated soils.

  1. Influences of humic acid and fulvic acid on horizontal leaching behavior of anthracene in soil barriers.

    PubMed

    Yu, Sheng; Li, Bang-Yu; Chen, Yi-Hu

    2015-12-01

    The influences of humic acid (HA) and fulvic acid (FA) on horizontal leaching behaviors of anthracene in barriers were investigated. Soil colloids (≤1 μm) were of concern because of their abilities of colloid-facilitated transport for hydrophobic organic compounds with soluble and insoluble organic matters. Through freely out of the barriers in the presence of soil colloids with FA added, the higher concentrations of anthracene were from 320 μg L(-1) (D1 and D3) to 390 μg L(-1) (D2 and D4) with 1 to 20 cm in length. The contents of anthracene were distributed evenly at 25 ng g(-1) dry weight (DW) (D1 and D3) and 11 ng g(-1) DW (D2 and D4) in barriers. Therefore, anthracene leaching behaviors were mainly induced by soil colloids with soluble organic matters. The insoluble organic matters would facilitate anthracene onto soil colloids and enhance the movement in and through porous media of soil matrix.

  2. Effects of simulated acid rain on soil fauna community composition and their ecological niches.

    PubMed

    Wei, Hui; Liu, Wen; Zhang, Jiaen; Qin, Zhong

    2017-01-01

    Acid rain is one of the severest environmental issues globally. Relative to other global changes (e.g., warming, elevated atmospheric [CO2], and nitrogen deposition), however, acid rain has received less attention than its due. Soil fauna play important roles in multiple ecological processes, but how soil fauna community responds to acid rain remains less studied. This microcosm experiment was conducted using latosol with simulated acid rain (SAR) manipulations to observe potential changes in soil fauna community under acid rain stress. Four pH levels, i.e., pH 2.5, 3.5, 4.5, and 5.5, and a neutral control of pH 7.0 were set according to the current pH condition and acidification trend of precipitation in southern China. As expected, we observed that the SAR treatments induced changes in soil fauna community composition and their ecological niches in the tested soil; the treatment effects tended to increase as acidity increased. This could be attributable to the environmental stresses (such as acidity, porosity and oxygen supply) induced by the SAR treatments. In addition to direct acidity effect, we propose that potential changes in permeability and movability of water and oxygen in soils induced by acid rain could also give rise to the observed shifts in soil fauna community composition. These are most likely indirect pathways of acid rain to affect belowground community. Moreover, we found that nematodes, the dominating soil fauna group in this study, moved downwards to mitigate the stress of acid rain. This is probably detrimental to soil fauna in the long term, due to the relatively severer soil conditions in the deep than surface soil layer. Our results suggest that acid rain could change soil fauna community and the vertical distribution of soil fauna groups, consequently changing the underground ecosystem functions such as organic matter decomposition and greenhouse gas emissions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Formation of diphenylthioarsinic acid from diphenylarsinic acid under anaerobic sulfate-reducing soil conditions.

    PubMed

    Hisatomi, Shihoko; Guan, Ling; Nakajima, Mami; Fujii, Kunihiko; Nonaka, Masanori; Harada, Naoki

    2013-11-15

    Diphenylarsinic acid (DPAA) is a toxic phenylarsenical compound often found around sites contaminated with phenylarsenic chemical warfare agents, diphenylcyanoarsine or diphenylchloroarsine, which were buried in soil after the World Wars. This research concerns the elucidation of the chemical structure of an arsenic metabolite transformed from DPAA under anaerobic sulfate-reducing soil conditions. In LC/ICP-MS analysis, the retention time of the metabolite was identical to that of a major phenylarsenical compound synthesized by chemical reaction of DPAA and hydrogen sulfide. Moreover the mass spectra for the two compounds measured using LC/TOF-MS were similar. Subsequent high resolution mass spectral analysis indicated that two major ions at m/z 261 and 279, observed on both mass spectra, were attributable to C12H10AsS and C12H12AsSO, respectively. These findings strongly suggest that the latter ion is the molecular-related ion ([M+H](+)) of diphenylthioarsinic acid (DPTA; (C6H5)2AsS(OH)) and the former ion is its dehydrated fragment. Thus, our results reveal that DPAA can be transformed to DPTA, as a major metabolite, under sulfate-reducing soil conditions. Moreover, formation of diphenyldithioarsinic acid and subsequent dimerization were predicted by the chemical reaction analysis of DPAA with hydrogen sulfide. This is the first report to elucidate the occurrence of DPAA-thionation in an anaerobic soil.

  4. Structural differences and the presence of unsubstituted amino groups in heparan sulphates from different tissues and species.

    PubMed Central

    Toida, T; Yoshida, H; Toyoda, H; Koshiishi, I; Imanari, T; Hileman, R E; Fromm, J R; Linhardt, R J

    1997-01-01

    This study presents a comparison of heparan sulphate chains isolated from various porcine and bovine tissues. 1H-NMR spectroscopy (500 MHz) was applied for structural and compositional studies on intact heparan sulphate chains. After enzymic digestion of heparan sulphate using heparin lyase I (EC 4.2.2.7) II and III (EC 4.2.2.8), the compositions of unsaturated disaccharides obtained were determined by analytical capillary electrophoresis. Correlations between the N-sulphated glucosamine residues and O-sulphation and between iduronic acid content and total sulphation were discovered using the data obtained by NMR and disaccharide analysis. Heparan sulphate chains could be classified into two groups based on the sulphation degree and the iduronic acid content. Heparan sulphate chains with a high degree of sulphation possessed also a significant number of iduronic acid residues and were isolated exclusively from porcine brain, liver and kidney medulla. The presence and amount of N-unsubstituted glucosamine residues (GlcNp) was established in all of the heparan sulphates examined. The structural context in which this residue occurs was demonstrated to be: high sulphation domain --> 4)-beta-D-GlcAp-(1 --> 4)-alpha-D-GlcNp-(1 --> 4)-beta-D-GlcAp-(1 --> low sulphation domain (where GlcNp is 2-amino-2-deoxyglucopyranose, and GlcAp is glucopyranosyluronic acid), based on the isolation and characterization of a novel, heparin lyase III-derived, GlcNp containing tetrasaccharide and hexasaccharide. The results presented suggest that structural differences may play a role in important biological events controlled by heparan sulphate in different tissues. PMID:9065769

  5. A Simulation of the Interaction of Acid Rain with Soil Minerals

    ERIC Educational Resources Information Center

    Schilling, Amber L.; Hess, Kenneth R.; Leber, Phyllis A.; Yoder, Claude H.

    2004-01-01

    The atmospheric issue of acid rains is subjected to a five-part laboratory experiment by concentrating on the chemistry of the infiltration process of acid rainwater through soils. This procedure of quantitative scrutiny helps students realize the efficacy of soil minerals in the consumption of surplus acidity in rainwater.

  6. A Simulation of the Interaction of Acid Rain with Soil Minerals

    ERIC Educational Resources Information Center

    Schilling, Amber L.; Hess, Kenneth R.; Leber, Phyllis A.; Yoder, Claude H.

    2004-01-01

    The atmospheric issue of acid rains is subjected to a five-part laboratory experiment by concentrating on the chemistry of the infiltration process of acid rainwater through soils. This procedure of quantitative scrutiny helps students realize the efficacy of soil minerals in the consumption of surplus acidity in rainwater.

  7. Declining acidic deposition begins reversal of forest-soil acidification in the northeastern U.S

    Treesearch

    Gregory B. Lawrence; Paul W. Hazlett; Ivan J. Fernandez; Rock Ouimet; Scott W. Bailey; Walter C. Shortle; Kevin T. Smith; Michael R. Antidormi

    2015-01-01

    Decreasing trends in acidic deposition levels over the past several decades have led to partial chemical recovery of surface waters. However, depletion of soil Ca from acidic deposition has slowed surface water recovery and led to the impairment of both aquatic and terrestrial ecosystems. Nevertheless, documentation of acidic deposition effects on soils has been...

  8. Organic Acids Regulation of Chemical-Microbial Phosphorus Transformations in Soils.

    PubMed

    Menezes-Blackburn, Daniel; Paredes, Cecilia; Zhang, Hao; Giles, Courtney D; Darch, Tegan; Stutter, Marc; George, Timothy S; Shand, Charles; Lumsdon, David; Cooper, Patricia; Wendler, Renate; Brown, Lawrie; Blackwell, Martin; Wearing, Catherine; Haygarth, Philip M

    2016-11-01

    We have used an integrated approach to study the mobility of inorganic phosphorus (P) from soil solid phase as well as the microbial biomass P and respiration at increasing doses of citric and oxalic acid in two different soils with contrasting agronomic P status. Citric or oxalic acids significantly increased soil solution P concentrations for doses over 2 mmol kg(-1). However, low organic acid doses (<2 mmol kg(-1)) were associated with a steep increase in microbial biomass P, which was not seen for higher doses. In both soils, treatment with the tribasic citric acid led to a greater increase in soil solution P than the dibasic oxalic acid, likely due to the rapid degrading of oxalic acids in soils. After equilibration of soils with citric or oxalic acids, the adsorbed-to-solution distribution coefficient (Kd) and desorption rate constants (k-1) decreased whereas an increase in the response time of solution P equilibration (Tc) was observed. The extent of this effect was shown to be both soil and organic acid specific. Our results illustrate the critical thresholds of organic acid concentration necessary to mobilize sorbed and precipitated P, bringing new insight on how the exudation of organic acids regulate chemical-microbial soil phosphorus transformations.

  9. Anti-inflammatory effect of chlorogenic acid on the IL-8 production in Caco-2 cells and the dextran sulphate sodium-induced colitis symptoms in C57BL/6 mice.

    PubMed

    Shin, Hee Soon; Satsu, Hideo; Bae, Min-Jung; Zhao, Zhaohui; Ogiwara, Haru; Totsuka, Mamoru; Shimizu, Makoto

    2015-02-01

    Chlorogenic acid (CHA) is an antioxidant polyphenol prevalent in human diet, with coffee, fruits, and vegetables being its main source. Effects of CHA and CHA metabolites were evaluated on the IL-8 production in human intestinal Caco-2 cells induced by combined stimulation with tumour necrosis factor alpha (TNFα) and H2O2. CHA and caffeic acid (CA) inhibited TNFα- and H2O2-induced IL-8 production. We also examined the in vivo effects of CHA and CA using dextran sulphate sodium (DSS)-induced colitis in mice. CHA attenuated DSS-induced body weight loss, diarrhea, fecal blood, and shortening of colon and dramatically improved colitis histological scores. Furthermore, increases in the mRNA expression of colonic macrophage inflammatory protein 2 and IL-1β, which were induced by DSS, were significantly suppressed by CHA supplementation. These results suggest that dietary CHA use may aid in the prevention of intestinal inflammatory conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Root-secreted malic acid recruits beneficial soil bacteria.

    PubMed

    Rudrappa, Thimmaraju; Czymmek, Kirk J; Paré, Paul W; Bais, Harsh P

    2008-11-01

    Beneficial soil bacteria confer immunity against a wide range of foliar diseases by activating plant defenses, thereby reducing a plant's susceptibility to pathogen attack. Although bacterial signals have been identified that activate these plant defenses, plant metabolites that elicit rhizobacterial responses have not been demonstrated. Here, we provide biochemical evidence that the tricarboxylic acid cycle intermediate L-malic acid (MA) secreted from roots of Arabidopsis (Arabidopsis thaliana) selectively signals and recruits the beneficial rhizobacterium Bacillus subtilis FB17 in a dose-dependent manner. Root secretions of L-MA are induced by the foliar pathogen Pseudomonas syringae pv tomato (Pst DC3000) and elevated levels of L-MA promote binding and biofilm formation of FB17 on Arabidopsis roots. The demonstration that roots selectively secrete L-MA and effectively signal beneficial rhizobacteria establishes a regulatory role of root metabolites in recruitment of beneficial microbes, as well as underscores the breadth and sophistication of plant-microbial interactions.

  11. Formation of chloroacetic acids from soil, humic acid and phenolic moieties.

    PubMed

    Fahimi, I J; Keppler, F; Schöler, H F

    2003-07-01

    The mechanism of formation of chloroacetates, which are important toxic environmental substances, has been controversial. Whereas the anthropogenic production has been well established, a natural formation has also been suggested. In this study the natural formation of chloroacetic acids from soil, as well as from humic material which is present in soil and from phenolic model substances has been investigated. It is shown that chloroacetates are formed from humic material with a linear relationship between the amount of humic acid used and chloroacetates found. More dichloroacetate (DCA) than trichloroacetate (TCA) is produced. The addition of Fe(2+), Fe(3+) and H(2)O(2) leads to an increased yield. NaCl was added as a source of chloride. We further examined the relationship between the structure and reactivity of phenolic substances, which can be considered as monomeric units of humic acids. Ethoxyphenol with built-in ethyl groups forms large amounts of DCA and TCA. The experiments with phenoxyacetic acid yielded large amounts of monochloroacetate (MCA). With other phenolic substances a ring cleavage was observed. Our investigations indicate that chloroacetates are formed abiotically from humic material and soils in addition to their known biotic mode of formation.

  12. Enhanced biodegradation of anthracene in acidic soil by inoculated Burkholderia sp. VUN10013.

    PubMed

    Somtrakoon, Khanitta; Suanjit, Sudarat; Pokethitiyook, Prayad; Kruatrachue, Maleeya; Lee, Hung; Upatham, Suchart

    2008-08-01

    The ability of Burkholderia sp. VUN10013 to degrade anthracene in microcosms of two acidic Thai soils was studied. The addition of Burkholderia sp. VUN10013 (initial concentration of 10(5) cells g(-1) dry soil) to autoclaved soil collected from the Plew District, Chanthaburi Province, Thailand, supplemented with anthracene (50 mg kg(-1) dry soil) resulted in complete degradation of the added anthracene within 20 days. In contrast, under the same test conditions but using autoclaved soil collected from the Kitchagude District, Chanthaburi Province, Thailand, only approximately 46.3% of the added anthracene was degraded after 60 days of incubation. In nonautoclaved soils, without adding the VUN10013 inocula, 22.8 and 19.1% of the anthracene in Plew and Kitchagude soils, respectively, were degraded by indigenous bacteria after 60 days. In nonautoclaved soil inoculated with Burkholderia sp. VUN10013, the rate and extent of anthracene degradation were considerably better than those seen in autoclaved soils or in uninoculated nonautoclaved soils in that only 8.2 and 9.1% of anthracene remained in nonautoclaved Plew and Kitchagude soils, respectively, after 10 days of incubation. The results showed that the indigenous microorganisms in the pristine acidic soils have limited ability to degrade anthracene. Inoculation with the anthracene-degrading Burkholderia sp. VUN10013 significantly enhanced anthracene degradation in such acidic soils. The indigenous microorganisms greatly assisted the VUN10013 inoculum in anthracene degradation, especially in the more acidic Kitchagude soil.

  13. [Effect of acetic acid on adsorption of acid phosphatase by some soil colloids and clay minerals].

    PubMed

    Zhao, Zhenhua; Huang, Qiaoyun; Jiang, Xin; Yu, Guifen; Wang, Fang; Li, Xueyuan

    2004-03-01

    This paper studied the effect of acetic acid with different concentrations and pH values on the adsorption of acid phosphatase by some soil colloids and clay minerals (SCCM). The results showed that the pH values for the maximum adsorption of the enzyme were between the IEP of the enzyme and the PZC of SCCM. In the acetic acid systems, the amount of the enzyme adsorbed by SCCM was in the order of goethite > yellow brown soil > latosol > kaolinite > delta-MnO2. A remarkable influence of acetic acid concentration on the adsorption amount and the binding energy of the enzyme was observed. With the increase of the concentration from 0 to 200 mmol.L-1 in the system, acetic acid exhibited an enhanced effect, followed by an inhibition action on the adsorption of the enzyme on SCCM. The changes of the binding energy (K value) for the enzyme on SCCM were on the contrary to those of the maximum adsorption. The possible mechanisms for the influence of acetic acid on the adsorption of enzyme by SCCM were also discussed.

  14. Strap grid tubular plate—a new positive plate for lead-acid batteries. Processes of residual sulphation of the positive plate

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Papazov, G.; Monahov, B.

    in the pores of the plate inner layers (close to the straps) increases. In concentrated H 2SO 4 solution the solubility of PbSO 4 crystals decreases. This slows down the rate of oxidation of PbSO 4 to PbO 2. Some parts of the PbSO 4 crystals in the PAM of the charged plate remain unoxidised (residual sulphation). Thus, the capacity of the plate is lower. Strap corrosion is the phenomenon that may limit the cycle life of SGT plates.

  15. Correlations between stream sulphate and regional SO2 emissions

    USGS Publications Warehouse

    Smith, R.A.; Alexander, R.B.

    1986-01-01

    The relationship between atmospheric SO2 emissions and stream and lake acidification has been difficult to quantify, largely because of the limitations of sulphur deposition measurements. Precipitation sulphate (SO4) records are mostly <5 yr in length and do not account for dry sulphur deposition. Moreover, a variable fraction of wet- and dry-deposited sulphur is retained in soils and vegetation and does not contribute to the acidity of aquatic systems. We have compared annual SO2 emissions for the eastern United States from 1976 to 1980 with stream SO4 measurements from fifteen predominantly undeveloped watersheds. We find that the two forms of sulphur are strongly correlated on a regional basis and that streams in the southeastern United States (SE) receive a smaller fraction (on average, 16%, compared with 24%) of regional sulphur emissions than do streams in the northeastern United States (NE). In addition to providing direct empirical evidence of a relationship between sulphur emissions and aquatic chemistry, these results suggest that there are significant regional differences in the fraction of deposited sulphur retained in basin soils and vegetation.The relationship between atmospheric SO//2 emissions and stream and lake acidification has been difficult to quantify, largely because of the limitations of sulphur deposition measurements. The authors have compared annual SO//2 emissions for the eastern United States from 1967 to 1980 with stream SO//4 measurements from fifteen predominantly undeveloped watersheds. They found that both the wet - and dry-deposited forms of sulphur are strongly correlated on a regional basis and that streams in the southeastern United States receive a smaller fraction (on average, 16%, compared with 24%) of regional sulphur emissions than do streams in the northeastern United States. In addition to providing direct empirical evidence of a relationship between sulphur emissions and aquatic chemistry, these results suggest that

  16. The influence of organic acids in relation to acid deposition in controlling the acidity of soil and stream waters on a seasonal basis.

    PubMed

    Chapman, Pippa J; Clark, Joanna M; Reynolds, Brian; Adamson, John K

    2008-01-01

    Much uncertainty still exists regarding the relative importance of organic acids in relation to acid deposition in controlling the acidity of soil and surface waters. This paper contributes to this debate by presenting analysis of seasonal variations in atmospheric deposition, soil solution and stream water chemistry for two UK headwater catchments with contrasting soils. Acid neutralising capacity (ANC), dissolved organic carbon (DOC) concentrations and the Na:Cl ratio of soil and stream waters displayed strong seasonal patterns with little seasonal variation observed in soil water pH. These patterns, plus the strong relationships between ANC, Cl and DOC, suggest that cation exchange and seasonal changes in the production of DOC and seasalt deposition are driving a shift in the proportion of acidity attributable to strong acid anions, from atmospheric deposition, during winter to predominantly organic acids in summer.

  17. Extraction of amino acids from soils and sediments with superheated water

    NASA Technical Reports Server (NTRS)

    Cheng, C. N.; Ponnamperuma, C.

    1974-01-01

    A method of extraction for amino acids from soils and sediments involving superheated water has been investigated. About 75-97 per cent of the amino acids contained in four soils of a soil profile from Illinois were extracted by this method. Deep penetration of water into soil aggregates and partial hydrolysis of peptide bonds during this extraction by water at high temperature are likely mechanisms responsible for the release of amino acids from samples. This extraction method does not require subsequent desalting treatments when analyses are carried out with an ion-exchange amino acid analyzer.

  18. Extraction of amino acids from soils and sediments with superheated water

    NASA Technical Reports Server (NTRS)

    Cheng, C. N.; Ponnamperuma, C.

    1974-01-01

    A method of extraction for amino acids from soils and sediments involving superheated water has been investigated. About 75-97 per cent of the amino acids contained in four soils of a soil profile from Illinois were extracted by this method. Deep penetration of water into soil aggregates and partial hydrolysis of peptide bonds during this extraction by water at high temperature are likely mechanisms responsible for the release of amino acids from samples. This extraction method does not require subsequent desalting treatments when analyses are carried out with an ion-exchange amino acid analyzer.

  19. Atmospheric sulfur as related to acid precipitation and soil fertility

    SciTech Connect

    Suarez, E.L.; Jones, U.S.

    1982-09-01

    Conductivity, pH, and ionic components were determined in the rainfall and particulate matter at Clemson, S.C., Experiment, Ga., and Franklin, N.C., using a wet/dry collector. Sulfur in the air was collected at Clemson on a 30-d interval in a standard lead peroxide sampler. Soil samples were taken from 15 locations in South Carolina and analyzed for sulfur. It was observed that the average loading concentration of anions in rainwater increased during the spring-summer months and decreased during the fall-winter months. Sulfuric and nitric acids were found to be the major components of acid rainfall. Rainfall and air deposition contributed approximately 10.7 and 1.8 kg/ha of sulfur per year, respectively, at Clemson. Atmospheric deposition from the particulate matter contributed an estimated 3.0 kg/ha of sulfur during the year. Increases in corn grain and silage yields were obtained with the application of 18 kg/ha of sulfur at Darlington, S.C. A relationship between applied sulfur and crop response for the other crops considered could not be established. A need for reevaluating the findings and recommendations for sulfur fertilizers was apparent because of the contribution of atmospheric-deposited sulfur to the soil and plant sulfur supply.

  20. Trans fatty acids exacerbate dextran sodium sulphate-induced colitis by promoting the up-regulation of macrophage-derived proinflammatory cytokines involved in T helper 17 cell polarization

    PubMed Central

    Okada, Y; Tsuzuki, Y; Sato, H; Narimatsu, K; Hokari, R; Kurihara, C; Watanabe, C; Tomita, K; Komoto, S; Kawaguchi, A; Nagao, S; Miura, S

    2013-01-01

    Numerous reports have shown that a diet containing large amounts of trans fatty acids (TFAs) is a major risk factor for metabolic disorders. Although recent studies have shown that TFAs promote intestinal inflammation, the underlying mechanisms are unknown. In this study, we examined the effects of dietary fat containing TFAs on dextran sodium sulphate (DSS)-induced colitis. C57 BL/6 mice were fed a diet containing 1·3% TFAs (mainly C16:1, C18:1, C18:2, C20:1, C20:2 and C22:1), and then colitis was induced with 1·5% DSS. Colonic damage was assessed, and the mRNA levels of proinflammatory cytokines and major regulators of T cell differentiation were measured. The TFA diet reduced survival and exacerbated histological damage in mice administered DSS compared with those fed a TFA-free diet. The TFA diet significantly elevated interleukin (IL)-6, IL-12p40, IL-23p19 and retinoic acid-related orphan receptor (ROR)γt mRNA levels in the colons of DSS-treated animals. Moreover, IL-17A mRNA levels were elevated significantly by the TFA diet, with or without DSS treatment. We also examined the expression of proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and peritoneal macrophages. These cells were exposed to TFAs (linoelaidic acid or elaidic acid) with or without LPS and the mRNA levels of various cytokines were measured. IL-23p19 mRNA levels were increased significantly by TFAs in the absence of LPS. Cytokine expression was also higher in LPS-stimulated cells exposed to TFAs than in unexposed LPS-stimulated cells. Collectively, our results suggest that TFAs exacerbate colonic inflammation by promoting Th17 polarization and by up-regulating the expression of proinflammatory cytokines in the inflamed colonic mucosa. PMID:24028683

  1. Trans fatty acids exacerbate dextran sodium sulphate-induced colitis by promoting the up-regulation of macrophage-derived proinflammatory cytokines involved in T helper 17 cell polarization.

    PubMed

    Okada, Y; Tsuzuki, Y; Sato, H; Narimatsu, K; Hokari, R; Kurihara, C; Watanabe, C; Tomita, K; Komoto, S; Kawaguchi, A; Nagao, S; Miura, S

    2013-12-01

    Numerous reports have shown that a diet containing large amounts of trans fatty acids (TFAs) is a major risk factor for metabolic disorders. Although recent studies have shown that TFAs promote intestinal inflammation, the underlying mechanisms are unknown. In this study, we examined the effects of dietary fat containing TFAs on dextran sodium sulphate (DSS)-induced colitis. C57 BL/6 mice were fed a diet containing 1·3% TFAs (mainly C16:1, C18:1, C18:2, C20:1, C20:2 and C22:1), and then colitis was induced with 1·5% DSS. Colonic damage was assessed, and the mRNA levels of proinflammatory cytokines and major regulators of T cell differentiation were measured. The TFA diet reduced survival and exacerbated histological damage in mice administered DSS compared with those fed a TFA-free diet. The TFA diet significantly elevated interleukin (IL)-6, IL-12p40, IL-23p19 and retinoic acid-related orphan receptor (ROR)γt mRNA levels in the colons of DSS-treated animals. Moreover, IL-17A mRNA levels were elevated significantly by the TFA diet, with or without DSS treatment. We also examined the expression of proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and peritoneal macrophages. These cells were exposed to TFAs (linoelaidic acid or elaidic acid) with or without LPS and the mRNA levels of various cytokines were measured. IL-23p19 mRNA levels were increased significantly by TFAs in the absence of LPS. Cytokine expression was also higher in LPS-stimulated cells exposed to TFAs than in unexposed LPS-stimulated cells. Collectively, our results suggest that TFAs exacerbate colonic inflammation by promoting Th17 polarization and by up-regulating the expression of proinflammatory cytokines in the inflamed colonic mucosa. © 2013 British Society for Immunology.

  2. Equilibrium sorption of phenanthrene by soil humic acids.

    PubMed

    Liang, Chongshan; Dang, Zhi; Xiao, Baohua; Huang, Weilin; Liu, Congqiang

    2006-06-01

    This study investigated the effect of chemical heterogeneity of humic acids (HAs) on the equilibrium sorption of phenanthrene by HA extracts. Six HA samples were extracted from three different soils with 0.5 M NaOH and 0.1 M Na4P2O7 and were characterized with elemental analysis, infrared spectrometry, and solid-state 13C nuclear magnetic resonance (NMR) spectrometry. The equilibrium sorption measurements were carried out with a batch technique and using the six HA solids as the sorbents and phenanthrene as the sorbate. The measured sorption isotherm data were fitted to the Freundlich equation. The results showed that, for the same soil, (i) the total HA mass extracted with Na4P2O7 was 13.7-22.6% less than that extracted with NaOH, (ii) the Na4P2O7-extracted HA had higher O/C atomic ratio, greater content of polar organic carbons (POC), and lower aliphatic carbon content than the NaOH-extracted HA, and (iii) the Na4P2O7-extracted HA exhibited greater sorption isotherm linearity and but not dramatic difference in sorption capacities than the NaOH extracted HA. The differences in the HA properties resulting from the two different extraction methods may be because NaOH can hydrolyze insoluble HA fractions such as fatty acid like macromolecules bound on soils whereas Na4P2O7 could not. As a result, the HAs extracted with the two different methods had different polarity and functionality which affected their sorption property for phenanthrene.

  3. Sulphate reduction associated with hardgrounds: Lithification afterburn!

    NASA Astrophysics Data System (ADS)

    Dickson, J. A. D.; Wood, R. A.; Bu Al Rougha, H.; Shebl, H.

    2008-03-01

    Negative excursions in δ13C profiles from platform carbonates that coincide with pyritised hardgrounds are commonly linked to subaerial exposure events, but we show here that they can also result from subsurface bacterially-mediated early cementation in addition to the precipitation of syndepositional marine cements. A non-soil-derived origin for δ13C-depleted micrites offers an alternative origin and bathymetric interpretation for these surfaces. The Lower Cretaceous Lekhwair Formation platform carbonate successions from offshore Abu Dhabi contain abundant hardgrounds that are important for both regional correlation and control of subsurface flow. The micrite from these hardgrounds have average δ13C values of + 0.7‰; 1.5‰ lower than non-hardground micrites that are similar to contemporary open ocean values. Hardground δ13C values are due to the addition of 13C-depleted carbonate, generated as a by-product of sulphate reduction, to the 'normal' marine calcite that caused hardground lithification. Pyritisation of the hardgrounds occurred before, during and after 'normal' calcite precipitation. The persistence of sulphate reduction after hardground lithification is shown by the presence of pyrite and low δ13C micrite in sediment up to a few mm above the hardgrounds.

  4. Short range variability of soil chemistry in three acid soils in Ontario, Canada

    SciTech Connect

    Fournier, R.E.; Morrison, I.K.; Hopkin, A.A. )

    1994-01-01

    The objective of this study was to assess the efficacy of soil sampling and analysis methodologies used in Canada's Acid Rain National Early Warning System (ARNEWS). During July and August of 1992, twenty-five soil pits were sampled and analyzed for available phosphorus (P); exchangeable potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), aluminum (Al), sodium (Na), sulfate-sulfur (SO4-S), boron (B), and molybdenum (Mo); total nitrogen (N), P, K, Ca, Mg, Fe, Cu, Mn, Zn, Al, Na, sulfur (S), B, nickel (Ni), lead (Pb), and organic matter (O.M.); pH; and cation exchange capacity (C.E.C.) at three ARNEWS sites across Ontario. The soils were: (i) a till-derived Ferro-Humic Podzol (Humic Haplorthod), (ii) a Humo-Ferric Podzol (Haplorthod) developed in coarse glaciofluvial sand, and (iii) a Dystric Brunisol (Dystrochrept). The three sites were similar in chemical composition except for available P, exchangeable Ca, Mn, total Mn, O.M., and pH. Sample numbers calculated to achieve [+-]10% error with 95% confidence were much higher in mineral horizons than in forest-floor horizons. Organic macro-elements and pH were found to be the least variable parameters while micro-elements were significantly more variable. Analyses are categorized into groups requiring similar numbers of samples. Other studies have found comparable levels of variability and their results are compared to coefficients of variation generated by the Ontario results. Variability within a pit was also observed and found to be less than that found across each 20- x 20-m site but still very significant. Overall, the variability results from other studies appear to be applicable to Ontario acid soils for common analyses. Investigations observing micro-elements, or which require high levels of accuracy, should incorporate pilot studies to ascertain the degree of variability for their location. 14 refs., 7 tabs.

  5. Analysis of the indices of acidity in the soil profile and their relationship with pedogenesis

    NASA Astrophysics Data System (ADS)

    Kokotov, Yu. A.; Sukhacheva, E. Yu.; Aparin, B. F.

    2016-01-01

    A new notion—an acidic trace of pedogenesis in the field of soil acidity—is suggested. This notion implies a three-dimensional representation of the distribution of soil acidity in the soil profile and can be graphically shown in three two-dimensional projections that can be combined on a common V-diagram. Such V-diagrams are individual for each particular soil profile. At the same time, they have some common phenomenology in their shapes and in the position in the acidity field. A tendency for the S-shaped form of acidic trace is manifested by a sharp decrease in pH upon the reduction of base saturation at the high and low values of this index and by small changes in pH at the moderate values of base saturation in the area of acid buffering of the soil profile. This phenomenon is related to the weak acidity and polyfunctionality of the soils as ionite systems. An acidic trace can be subdivided into several characteristic parts related to different pedogenetic processes in their interaction. Its position in the field of acidity is largely determined by the acidity of parent material. Acidic traces of different types of soils in the northwestern Russia are discussed. It is argued that V-diagrams should be analyzed together with other soil characteristics.

  6. Capillary zone electrophoresis of soil humic acid fractions obtained by coupling size-exclusion chromatography and polyacrylamide gel electrophoresis.

    PubMed

    Cavani, Luciano; Ciavatta, Claudio; Trubetskaya, Olga E; Reznikova, Olga I; Afanas'eva, Gaida V; Trubetskoj, Oleg A

    2003-01-03

    Capillary zone electrophoresis (CZE) was used for characterisation of soil humic acid (HA) fractions obtained by coupling size-exclusion chromatography with polyacrylamide gel electrophoresis, on the basis of their molecular size and electrophoretic mobility. CZE was conducted using several low alkaline buffers as background electrolyte (BGE): 50 mM carbonate, pH 9.0; 50 mM phosphate, pH 8.5; 50 mM borate, pH 8.3; 50 mM Tris-borate+1 mM EDTA+7 M urea+0.1% sodium dodecyl sulphate (SDS), pH 8.3. Independently of BGE conditions, the effective electrophoretic mobility of HA fractions were in good agreement with their molecular size. The better resolution of HA were obtained in Tris-borate-EDTA buffer with urea and SDS. This results indicated that CZE, mostly with BGE-contained disaggregating agents, is useful for separating HAs in fractions with different molecular sizes.

  7. Transformation of external sulphate and its effect on phosphorus mobilization in Lake Moshui, Wuhan, China.

    PubMed

    Yu, Fenfang; Zou, Jiajia; Hua, Yumei; Zhang, Shaohui; Liu, Guanglong; Zhu, Duanwei

    2015-11-01

    Average concentrations of sulphate in lakes continue to increase sharply. The response of phosphorus to sulphate input is of great importance due to the relationship between eutrophication and ecological health. A four-week experiment was conducted under simulated conditions using samples from a heavily polluted lake, Lake Moshui, in Wuhan, China, to examine the influence of external sulphate on phosphorus release and the transformation of sulphate. The results showed that the diffusion of sulphate into the sediments promoted the proliferation of sulphate-reducing bacteria (SRB) and the reduction of sulphate. Acetic acid was consumed due to sulphate reduction. The soluble reactive phosphorus (SRP) and soluble Fe measured with diffusive equilibration in thin-films (DET) probes increased significantly after the input of sulphate. The content of SRP was consistent with the variation in both the SRB number and the S(0) content in the sediments. The maximum SRP concentration of 100.43 mg L(-1) was recorded 3 cm below the sediment-water interface on the 29th d, which was more than twice the value of the control. There was a positive correlation between concentrations of Fe and SRP in the overlying water and the pore water of the sediments.

  8. Effects of organic acids on cadmium and copper sorption and desorption by two calcareous soils.

    PubMed

    Najafi, Sarvenaz; Jalali, Mohsen

    2015-09-01

    Low molecular weight organic acids (LMWOAs) present in soil alter equilibrium pH of soil, and consequently, affect heavy metal sorption and desorption on soil constitutes. This study was conducted to investigate the effects of different concentrations (0.1, 1, 2.5, 5, 10, 30, 40, 50, 70, and 100 mM) of citric, malic, and oxalic acids on sorption and desorption of cadmium (Cd) and copper (Cu) in two calcareous soils. Increasing the concentrations of three LMWOAs decreased the equilibrium pH of soil solutions. The results indicated that increase in organic acids concentrations generally reduced Cd and Cu sorption in soils. Increase concentrations of LMWOAs generally promoted Cd and Cu desorption from soils. A valley-like curve was observed for desorption of Cu after the citric acid concentration increment in soil 2. Increasing the concentrations of three LMWOAs caused a marked decrease in Kd(sorp) values of Cd and Cu in soils. In general, citric acid was the most effective organic acid in reducing sorption and increasing desorption of both metals, and oxalic acid had the minimal impact. The results indicated that LMWOAs had a greater impact on Cu sorption and desorption than Cd, which can be attributed to higher stability constants of organic acids complexes with Cu compared to Cd. It can be concluded that by selecting suitable type and concentration of LMWOAs, mobility, and hence, bioavailability of heavy metals can be changed. So, environmental implications concerning heavy metals mobility might be derived from these findings.

  9. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS II: OPTIMIZATION OF CHROMATOGRAPHY AND EXTRACTION

    EPA Science Inventory

    With the objective of detecting and quantitating low concentrations of perfluorinated carboxylic acids (PFCAs), including perfluorinated octanoic acid (PFOA), in soils, we compared the analytical suitability of liquid chromatography columns containing three different stationary p...

  10. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS II: OPTIMIZATION OF CHROMATOGRAPHY AND EXTRACTION

    EPA Science Inventory

    With the objective of detecting and quantitating low concentrations of perfluorinated carboxylic acids (PFCAs), including perfluorinated octanoic acid (PFOA), in soils, we compared the analytical suitability of liquid chromatography columns containing three different stationary p...

  11. Studies on the metabolism of oestrone sulphate. Comparative perfusions of oestrone and oestrone sulphate through isolated rat livers

    PubMed Central

    Höller, Michael; Grochtmann, Wilhelm; Napp, Mechthild; Breuer, Heinz

    1977-01-01

    The metabolism of [4-14C]oestrone and of [6,7-3H2]oestrone sulphate was studied during cyclic perfusion and once-through perfusion of the isolated rat liver. The following results were obtained. 1. As shown by once-through perfusion, the two steroids are metabolized differently during the first passage through the organ. [4-14C]Oestrone was taken up by the liver and partly delivered as oestradiol-17β and oestriol into the medium. After uptake of [6,7-3H2]oestrone sulphate, only oestrone, liberated by hydrolysis, was delivered into the medium; no oestradiol-17β or oestriol could be detected in the medium after one passage through the organ. This indicates that intracellular oestrone, which was taken up as such, and oestrone, which derived from intracellular hydrolysis, may be metabolized in different compartments of the liver cell. 2. The results of the cyclic perfusion showed that intracellular oestrone is preferentially conjugated with glucuronic acid, and subsequently excreted into the bile. Intracellular oestrone sulphate is preferably reduced to oestradiol sulphate, thus indicating that oestrone sulphate is a better substrate for the 17β-hydroxy steroid oxidoreductase than is oestrone. 3. Albumin-bound oestrone sulphate acts as a large reservoir, and in contrast with free oestrone is protected from enzyme attack by its strong binding to albumin. 4. Oestrone sulphate is partly converted into the hormonally active oestrone by liver tissue. This suggests that liver not only inactivates oestrogens, but also provides the organism with oestrone, which is subsequently readily taken up by other organs. PMID:597232

  12. Liquid Swine Manure Can Kill Verticillium dahliae Microsclerotia in Soil by Volatile Fatty Acid, Nitrous Acid, and Ammonia Toxicity.

    PubMed

    Conn, Kenneth L; Tenuta, Mario; Lazarovits, George

    2005-01-01

    ABSTRACT In previous studies, liquid swine manure (LSM) was sometimes shown to reduce Verticillium wilt of potato caused by Verticillium dahliae. We also observed that microsclerotia of this fungus died within 1 day, or between 3 and 6 weeks, after addition of LSM to some acid soils and within 1 week in some alkaline soils. In this study, we demonstrated that a volatile fatty acid (VFA) mixture with an identical concentration of VFAs as that found in an effective LSM reduced germination in an acid soil (pH 5.1) to the same extent as the LSM after 1 day of exposure. Germination was reduced by 45, 75, and 90% in the 10, 20, and 40% ([wt/wt] soil moisture) treatments, respectively, with the latter being equivalent to an application of 80 hl/ha. Addition to this acid soil of 19 LSMs (30% [wt/wt] soil moisture) collected from different producers resulted in complete kill of microsclerotia with 12 manures. Effective manures had a total concentration of nonionized forms of VFAs in soil solution of 2.7 mM or higher. In some acid soils (pH 5.8), addition of LSM (40% [wt/wt] soil moisture) did not kill microsclerotia until 3 to 6 weeks later. Here, a reduction in viability of microsclerotia was attributed to the accumulation of 0.06 mM nitrous acid in the soil solution at 4 weeks. When an LSM was added (40% [wt/wt] soil moisture) to an alkaline soil (pH 7.9) where VFAs are not toxic, microsclerotia germination was reduced by 80% after 1 week. Here the pH increased to 8.9 and the concentration of ammonia reached 30 mM in the soil solution. An ammonium chloride solution having an equivalent concentration of ammonium as the manure was shown to have the same spectrum of toxicity as the manure in assays ranging from pH 7 to 9, both in solutions and above the solutions. At pH 9, the concentration of ammonia reached 18 mM and 100% mortality of microsclerotia occurred. Thus, in acid soils, LSM can kill microsclerotia of V. dahliae by VFA and/or nitrous acid toxicity and in alkaline

  13. Fractionation of bamboo hemicelluloses by graded saturated ammonium sulphate.

    PubMed

    Guan, Ying; Zhang, Bing; Qi, Xian-Ming; Peng, Feng; Yao, Chun-Li; Sun, Run-Cang

    2015-09-20

    The hemicelluloses were isolated with 10% KOH at 25°C from dewaxed and delignified bamboo powder. The alkali-soluble hemicelluloses from Sinocalamus affinis were fractionated by ammonium sulphate precipitation method. The bamboo alkali-soluble hemicelluloses yielded seven hemicellulosic fractions obtained at 0, 5, 15, 25, 40, 55, and 70% saturation with ammonium sulphate. It was found that the more branched hemicelluloses were precipitated at higher ammonium sulphate concentrations (55 and 70%), the more linear hemicelluloses were precipitated at lower ammonium sulphate concentrations (0, 5, 15, 25, and 40%). The molecular weights of hemicellulosic fractions become lower from 35,270 (H0) to 18,680 (H70)gmol(-1) with the increasing concentrations of saturated ammonium sulphate from 0 to 70%. Based on the FT-IR, (1)H, (13)C and 2D HSQC NMR studies, the alkali-soluble hemicelluloses were 4-O-methyl-glucuronoarabinoxylans composed of the (1→4)-linked β-d-xylopyranosyl backbone with branches at O-3 of α-L-arabinofuranosyl or at O-2 of 4-O-methyl-α-d-glucuronic acid.

  14. Fixed combination of hyaluronic acid and chondroitin-sulphate oral formulation in a randomized double blind, placebo controlled study for the treatment of symptoms in patients with non-erosive gastroesophageal reflux.

    PubMed

    Palmieri, B; Merighi, A; Corbascio, D; Rottigni, V; Fistetto, G; Esposito, A

    2013-12-01

    Proton pump inhibitors (PPIs) are a major breakthrough in the medical management of gastroesophageal reflux disease (GERD). In several patients with non erosive reflux disease symptoms (NERD) the response to PPIs is partial or limited and symptoms relief needs the administration of additional medications. The aim of this study was to evaluate the effect of a new medical device, based on an oral fixed combination of hyaluronic acid and chondroitin-sulphate (HA+CS), in a bioadhesive carrier, in adults with symptoms of non erosive gastroesophageal reflux and with a low response to PPIs. Twenty patients who had experienced heartburn and/or acid regurgitation for at least 3 days during a 7 day run-in period, without endoscopic mucosal breaks, were randomized in a double blind crossover study to receive four daily doses of a fixed oral combination of HA+CS and placebo for 14 days. Relief of cardinal symptoms of GERD was evaluated at the end of each period. A significant greater Sum of Symptoms Intensity Difference, compared to placebo, was observed after HA+CS treatment (-2.7 vs 0.5 - p < 0.01), being both heartburn (-1.6 vs 0.5 - p < 0.03) and acid regurgitation (-1.1 vs 0.1 - p < 0.03) significantly improved by the medical device. A speed of action ≤ 30 min was significantly more frequently reported by patients during HA+CS administration than with placebo (60% vs 30% - p = 0.05). Total disappearance of symptoms was observed in 50% of the patients compared to 10% during placebo administration (p = 0.01 between group comparison). A fixed combination of HA+CS has demonstrated to be effective in gastroesophageal reflux control, with a rapid onset of action.

  15. Metagenomic analysis of the rhizosphere soil microbiome with respect to phytic acid utilization.

    PubMed

    Unno, Yusuke; Shinano, Takuro

    2013-01-01

    While phytic acid is a major form of organic phosphate in many soils, plant utilization of phytic acid is normally limited; however, culture trials of Lotus japonicus using experimental field soil that had been managed without phosphate fertilizer for over 90 years showed significant usage of phytic acid applied to soil for growth and flowering and differences in the degree of growth, even in the same culture pot. To understand the key metabolic processes involved in soil phytic acid utilization, we analyzed rhizosphere soil microbial communities using molecular ecological approaches. Although molecular fingerprint analysis revealed changes in the rhizosphere soil microbial communities from bulk soil microbial community, no clear relationship between the microbiome composition and flowering status that might be related to phytic acid utilization of L. japonicus could be determined. However, metagenomic analysis revealed changes in the relative abundance of the classes Bacteroidetes, Betaproteobacteria, Chlorobi, Dehalococcoidetes and Methanobacteria, which include strains that potentially promote plant growth and phytic acid utilization, and some gene clusters relating to phytic acid utilization, such as alkaline phosphatase and citrate synthase, with the phytic acid utilization status of the plant. This study highlights phylogenetic and metabolic features of the microbial community of the L. japonicus rhizosphere and provides a basic understanding of how rhizosphere microbial communities affect the phytic acid status in soil.

  16. Effects of surfactants on low-molecular-weight organic acids to wash soil zinc.

    PubMed

    Chen, Yue; Zhang, Shirong; Xu, Xiaoxun; Yao, Ping; Li, Ting; Wang, Guiyin; Gong, Guoshu; Li, Yun; Deng, Ouping

    2016-03-01

    Soil washing is an effective approach to the removal of heavy metals from contaminated soil. In this study, the effects of the surfactants sodium dodecyl sulfate, Triton X-100, and non-ionic polyacrylamide (NPAM) on oxalic acid, tartaric acid, and citric acid used to remove zinc from contaminated soils were investigated. The Zn removal efficiencies of all washing solutions showed a logarithmic increase with acid concentrations from 0.5 to 10.0 g/L, while they decreased as pH increased from 4 to 9. Increasing the reaction time enhanced the effects of surfactants on Zn removal efficiencies by the acids during washing and significantly (P < 0.05) improved the removal under some mixed cases. Oxalic acid suffered antagonistic effects from the three surfactants and seriously damaged soil nutrients during the removal of soil Zn. Notably, the three surfactants caused synergistic effects on tartaric and citric acid during washing, with NPAM leading to an increase in Zn removal by 5.0 g/L citric acid of 10.60 % (P < 0.05) within 2 h. NPAM also alleviated the loss of cation exchange capacity of washed soils and obviously improved soil nitrogen concentrations. Overall, combining citric acid with NPAM offers a promising approach to the removal of zinc from contaminated soil.

  17. Selecting Rhizobium meliloti for inoculation of alfalfa planted in acid soils

    SciTech Connect

    Lowendorf, H.S.; Alexander, M.

    1983-01-01

    The study was conducted to obtain Rhizobium meliloti strains suitable for use with alfalfa grown in acid soils. Thirteen strains of R. meliloti were examined for their ability to grow in acidified culture media and seven of these were characterized for the ability to surive in acid and limed nonsterile soils or grow in the presence of the host legume, Medicago sativa L. The pH values of the most acid, defined medium that permitted growth of the bacteria from a small inoculum ranged from pH 5.3 to 6.0. For R. meliloti 411SE1 and GH1-1SE1, the minimum pH that allowed for growth, the critical pH, was not a dependable indicator of survival in a more acid medium. Strains of R. meliloti with relatively low critical pH values survived better in a limed soil but not in acid soils than strains with higher critical pH values. Three strains of R. meliloti previously identified as good inoculants for alfalfa in acid soils did not consistently survive beter than other strains in a planted or unplanted acid soil of pH 5.3. However, the plants increase the population densities of these three strains more than other strains. These results suggest that R. meliloti strains suitable for inoculation of alfalfa in acid soils may be selected not by simple saprophytic properties but by their stimulation by the host legume in acid soils.

  18. Biogenic arsenic volatilisation from an acidic wetland soil

    NASA Astrophysics Data System (ADS)

    Ilgen, Gunter; Huang, Jen-How; Lu, Shipeng; Tian, Liyan; Alewell, Christine

    2014-05-01

    Biogenic arsenic (As) volatilisation was budgeted at 26000 t yr-1as the largest input of the global As release into the atmosphere, thereby playing an important role in the biogeochemical cycle of As in the surface environment. In order to quantify As volatilisation from wetland soils and to elucidate the geochemical and microbiological factors governing As volatilisation, a series of incubations with an acidic wetland soil collected in NE-Bavaria in Germany were performed at 15oC for 4 months with addition of NaN3, arsenite (As(III)), FeCl3, NaSO4 and NaOAc with N2 and air in the headspace. Speciation of gaseous As in the headspace using GC-ICP-MS/ ESI-MS coupling showed the predominance of either arsine (AsH3) or trimethylarsine ((CH3)3As) in all treatments during the time course of incubation. Monomethylarsine ((CH3)AsH2) and dimethylarsine ((CH3)2AsH) could be only detected in trace amounts. Arsenic speciation in porewater with HPLC-ICP-MS revealed the predominance of As(III) and methylated As was never detectable. Arsenic volatilisation summed to 2.3 ng As (88% as AsH3) in the control incubations, which accounted for ~0.25 % of the total As storage in the wetland soil. Treatments with 10 mM NaN3 resulted in emission of only 0.03 ng As. In contrast, addition of 10 mM NaOAc stimulated microbial activities in wetland soils and subsequently rose As volatilisation to 8.5 ng As. It could be therefore concluded that As volatilisation from the wetland soils was mainly biological. Spiking 67 μM As(III) increased 10 times of As volatilisation and the proportion of methylated arsines increased to 66%, which is supposed to be caused by the largely enhanced As availability in porewater for microbes (480 ppb, ~65 times higher than those in the controls). Adding 10 mM FeCl3 stimulated microbial Fe(III) reducing activities but suppressed other microbial activities by lowering soil pH from 5 to 3.6, decreasing consequently As volatilisation to 0.3 ng As. The much lower redox

  19. [Effects of Low-Molecular-Weight Organic Acids on the Speciation of Pb in Purple Soil and Soil Solution].

    PubMed

    Liu, Jiang; Jiang, Tao; Huang, Rong; Zhang, Jin-zhong; Chen, Hong

    2016-04-15

    Lead (Pb) in purple soil was selected as the research target, using one-step extraction method with 0.01 mol · L⁻¹ sodium nitrate as the background electrolyte to study the release effect of citric acid (CA), tartaric acid (TA) and acetic acid (AC) with different concentrations. Sequential extraction and geochemical model (Visual Minteq v3.0) were applied to analyze and predict the speciation of Pb in soil solid phase and soil solution phase. Then the ebvironmental implications and risks of low-molecule weight organic acid (LMWOA) on soil Pb were analyzed. The results indicated that all three types of LMWOA increased the desorption capacity of Pb in purple soil, and the effect followed the descending order of CA > TA > AC. After the action of LMWOAs, the exchangeable Pb increased; the carbonate-bound Pb and Fe-Mn oxide bound Pb dropped in soil solid phase. Organic bound Pb was the main speciation in soil solution phase, accounting for 45.16%-75.05%. The following speciation of Pb in soil solution was free Pb, accounting for 22.71%-50.25%. For CA and TA treatments, free Pb ions and inorganic bound Pb in soil solution increased with increasing LMWOAs concentration, while organic bound Pb suffered a decrease in this process. An opposite trend for AC treatment was observed compared with CA and TA treatments. Overall, LMWOAs boosted the bioavailability of Pb in purple soil and had a potential risk to contaminate underground water. Among the three LMWOAs in this study, CA had the largest potential to activate soil Pb.

  20. Phytoremediation of uranium-contaminated soils: Role of organic acids in triggering uranium hyperaccumulation in plants

    SciTech Connect

    Huang, J.W.; Blaylock, M.J.; Kapulnik, Y.; Ensley, B.D.

    1998-07-01

    Uranium phytoextraction, the use of plants to extract U from contaminated soils, is an emerging technology. The authors report on the development of this technology for the cleanup of U-contaminated soils. In this research, they investigated the effects of various soil amendments on U desorption from soil to soil solution, studied the physiological characteristics of U uptake and accumulation in plants, and developed techniques to trigger U hyperaccumulation in plants. A key to the success of U phytoextraction is to increase soil U availability to plants. The authors have found that some organic acids can be added to soils to increase U desorption from soil to soil solution and to trigger a rapid U accumulation in plants. Of the organic acids (acetic acid, citric acid, and malic acid) tested, citric acid was the most effective in enhancing U accumulation in plants. Shoot U concentrations of Brassica juncea and Brassica chinensis grown in a U-contaminated soil increased from less than 5 mg kg{sup {minus}1} to more than 5,000 mg kg{sup {minus}1} in citric acid-treated soils. To their knowledge, this is the highest shoot U concentration reported for plants grown on U-contaminated soils. Using this U hyperaccumulation technique, they are now able to increase U accumulation in shoots of selected plant species grown in two U-contaminated soils by more than 1,000-fold within a few days. The results suggest that U phytoextraction may provide an environmentally friendly alternative for the cleanup of U-contaminated soils.

  1. Effect of soil acidity factors on yields and foliar composition of tropical root crops

    SciTech Connect

    Abruna-Rodriguez, F.; Vicente-Chandler, J.I. Rivera, E.; Rodriguez, J.

    1982-09-01

    Tropical root crops, a major source of food for subsistence farmers, varied in their sensitivity to soil acidity factors. Tolerance to soil acidity is an important characteristic of crops for the humid tropics where soils are often very acid and lime-scarce and expensive. Experiments on two Ultisols and an Oxisol showed that three tropical root crops differed markedly in sensitivity to soil acicity factors. Yams (Dioscorea alata L.) were very sensitive to soil acidity with yields on a Ultisol decreasing from 70% of maximum when Al saturation of the effective cation exchange capacity of the soil was 10 to 25% of maximum when Al saturation was 40%. On the other hand, cassava (Manihot esculenta Crantz) was very tolerant to high levels of soil acidity, yielding about 85% of maximum with 60% Al saturation. Taniers (Xanthosoma sp.) were intermediate between yams and cassava in their tolerance to soil acidity yielding about 60% of maximum with 50% Al saturation of the soil. Foliar composition of cassava was not affected by soil acidity levels and that of yams and taniers was also unaffected except for Ca content which decreased with decreasing soil pH and increasing Al saturation.Response of these tropical root crops to soil acidity components was far more striking on Ultisols than on the Oxisol. For yams, soils should be limed to about pH 5.5 with essentially no exhangeable Al/sup 3 +/ present whereas high yields of taniers can be obtained at about pH 4.8 with 20% exchangeable Al/sup 3 +/ and of cassava at pH as low as 4.5 with 60% exchangeable Al/sup 3 +/.

  2. Early indications of soil recovery from acidic deposition in U.S. red spruce forests

    Treesearch

    Gregory B. Lawrence; Walter C. Shortle; Mark B. David; Kevin T. Smith; Richard A. Warby; Andrei G. Lapenis

    2012-01-01

    Forty to fifty percent decreases in acidic deposition through the 1980s and 1990s led to partial recovery of acidified surface waters in the northeastern United States; however, the limited number of studies that have assessed soil change found increased soil acidification during this period. From existing data, it's not clear whether soils continued to worsen in...

  3. Influence of different forms of acidities on soil microbiological properties and enzyme activities at an acid mine drainage contaminated site.

    PubMed

    Sahoo, Prafulla Kumar; Bhattacharyya, Pradip; Tripathy, Subhasish; Equeenuddin, Sk Md; Panigrahi, M K

    2010-07-15

    Assessment of microbial parameters, viz. microbial biomass, fluorescence diacetate, microbial respiration, acid phosphatase, beta-glucosidase and urease with respect to acidity helps in evaluating the quality of soils. This study was conducted to investigate the effects of different forms of acidities on soil microbial parameters in an acid mine drainage contaminated site around coal deposits in Jainta Hills of India. Total potential and exchangeable acidity, extractable and exchangeable aluminium were significantly higher in contaminated soil compared to the baseline (p<0.01). Different forms of acidity were significantly and positively correlated with each other (p<0.05). Further, all microbial properties were positively and significantly correlated with organic carbon and clay (p<0.05). The ratios of microbial parameters with organic carbon were negatively correlated with different forms of acidity. Principal component analysis and cluster analyses showed that the microbial activities are not directly influenced by the total potential acidity and extractable aluminium. Though acid mine drainage affected soils had higher microbial biomass and activities due to higher organic matter content than those of the baseline soils, the ratios of microbial parameters/organic carbon indicated suppression of microbial growth and activities due to acidity stress.

  4. Modeling the contribution of soil fauna to litter decomposition influenced by acidic deposition

    SciTech Connect

    Cai, B.; Loucks, O.L; Kuperman, R. Argonne National Lab., IL )

    1993-06-01

    The effect of acidic deposition on soil pH and therefore on soil invertebrates and litter decomposition is being investigated in oak-hickory forests across a three-state, midwest, pollution gradient. The role of soil invertebrates has been assessed previously through the use of feeding, assimilation and respiratory rates. These energetic parameters depend strongly on the form of the allometric equations which have been improved here by incorporating uncertainties in body and population size. Results show that changes in reproduction and turnover dynamics of soil invertebrates (particularly of earthworms) due to acid-induced changes in soil pH explains observed patterns in litter depth.

  5. Sulphate release from building rubble of WWII

    NASA Astrophysics Data System (ADS)

    Mekiffer, Beate; Wessolek, Gerd; Vogeler, Iris; Brettholle, Mareike

    2010-05-01

    Sulphate concentration in the upper aquifer of Berlin, Germany is increasing continuously since 40 years. In downtown Berlin they particular exceed the precaution values of drinking water ordinance. We assume that the main source of sulphate in the groundwater is technogenic material, which is part of building rubble from WW II bombing. Nearly 115 Mio t of this material have been deposited in Berlin. Our aim is, ­ to identify rubble components which contain S and to quantify the S-pool of this material ­ to identify factors, influencing the release of SO4 and ­ to predict sulphate release from building rubble of WW II We analyzed total and water soluble S of various components and the fine earth fraction of the soils containing the rubble. We investigated the influence of physical and chemical parameters on the release of SO4 using unsaturated column experiments (With an automatic percolation system). Thereby, the particle size, the flow rate and the pH of the solution has been varied. Among the components, slag shows the highest total S-contents of up to 0,7% . Lignite Coal-ashes from Lusatia, Germany are also rich in SO4. The total S of brick varies between 0,01% and 0,3%. Mortar shows S-Values between 0,08 and 0,12%. In 75% of all samples show total S of less than 0,14%. There was no significant correlation between total S-amount and water-soluble SO4, which is caused by different chemical compounds in the samples. In the percolation experiments technogenic components with grain size <2mm cause a higher density, resulting in a lower percolation velocity. The concentration of ions in the according leachate is higher than in the leachate of coarse fraction (2 - 20mm). Gypsum-rich material (10%) released constant SO4 -concentration over the whole experiment. Slag-rich material released high initial SO4-concentrations which then fastly decreased. We concluded, that the kind of technogenic component and its grain size strongly influences the release of SO4 to the

  6. Soil-calcium depletion linked to acid rain and forest growth in the eastern United States

    USGS Publications Warehouse

    Lawrence, Gregory B.; Huntington, T.G.

    1999-01-01

    Since the discovery of acid rain in the 1970's, scientists have been concerned that deposition of acids could cause depletion of calcium in forest soils. Research in the 1980's showed that the amount of calcium in forest soils is controlled by several factors that are difficult to measure. Further research in the 1990's, including several studies by the U.S. Geological Survey, has shown that (1) calcium in forest soils has decreased at locations in the northeastern and southeastern U.S., and (2) acid rain and forest growth (uptake of calcium from the soil by roots) are both factors contributing to calcium depletion.

  7. 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.

  8. Organic amendment effects on the transformation and fractionation of aluminum in acidic sandy soil

    USDA-ARS?s Scientific Manuscript database

    This study was attempted to evaluate the transformation of aluminum (Al) in an acidic sandy soil amended with composts (yard waste, yard + municipal waste, GreenEdge®, and synthetic humic acid), based on soil Al fractionation by single and sequential extraction. The compost amendment significantly i...

  9. Humic acid toxicity in biologically treated soil contaminated with polycyclic aromatic hydrocarbons and pentachlorophenol.

    PubMed

    Nieman, J K C; Sims, R C; Sorensen, D L; McLean, J E

    2005-10-01

    Contaminated soil from a land treatment unit at the Libby Groundwater Superfund Site in Libby, MT, was amended with 14C pyrene and incubated for 396 days to promote biodegradation and the formation of soil-associated bound residues. Humic and fulvic acids were extracted from the treated soil microcosms and analyzed for the presence of pyrene residues. Biologic activity promoted 14C association with the fulvic acid fraction, but humic acid-associated 14C did not increase with biologic activity. The Aboatox flash toxicity assay was used to assess the toxicity of humic and fulvic acid fractions. The fulvic acid gave no toxic response, but the humic acid showed significant toxicity. The observed toxicity was likely associated with pentachlorophenol, a known contaminant of the soil that was removed by solvent extraction of the humic acid and that correlated well with toxicity reduction.

  10. 7 CFR 160.10 - Sulphate wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Sulphate wood turpentine. 160.10 Section 160.10... STANDARDS FOR NAVAL STORES General § 160.10 Sulphate wood turpentine. The designation “sulphate wood... in the sulphate process of cooking wood pulp, and commonly known as sulphate turpentine or sulphate...

  11. 7 CFR 160.10 - Sulphate wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Sulphate wood turpentine. 160.10 Section 160.10... STANDARDS FOR NAVAL STORES General § 160.10 Sulphate wood turpentine. The designation “sulphate wood... in the sulphate process of cooking wood pulp, and commonly known as sulphate turpentine or sulphate...

  12. Acid precipitation effects on soil pH and base saturation of exchange sites

    Treesearch

    W. W. McFee; J. M. Kelly; R. H. Beck

    1976-01-01

    The typical values and probable ranges of acid-precipitation are evaluated in terms of their theoretical effects on pH and cation exchange equilibrium of soils characteristic of the humid temperature region. The extent of probable change in soil pH and the time required to cause such a change are calculated for a range of common soils. Hydrogen ion input by acid...

  13. Climate change impacts on forest soil critical acid loads and exceedances at a national scale

    Treesearch

    Steven G. McNulty; Erika C. Cohen; Jennifer A. Moore Myers

    2013-01-01

    Federal agencies are currently developing guidelines for forest soil critical acid loads across the United States. A critical acid load is defined as the amount of acid deposition (usually expressed on an annual basis) that an ecosystem can absorb. Traditionally, an ecosystem is considered to be at risk for health impairment when the critical acid load exceeds a level...

  14. Aliphatic, Cyclic, and Aromatic Organic Acids, Vitamins, and Carbohydrates in Soil: A Review

    PubMed Central

    Vranova, Valerie; Rejsek, Klement; Formanek, Pavel

    2013-01-01

    Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic) and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research. PMID:24319374

  15. Aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil: a review.

    PubMed

    Vranova, Valerie; Rejsek, Klement; Formanek, Pavel

    2013-11-10

    Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic) and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research.

  16. Crossing the pedogenetic threshold: Apparent phosphorus limitation by soil microorganisms in unglaciated acidic eastern hardwood forests

    NASA Astrophysics Data System (ADS)

    Deforest, J. L.; Smemo, K. A.; Burke, D. J.

    2010-12-01

    The availability of soil phosphorus (P) can significantly influence microbial community composition and the ecosystem-level processes they mediate. However, the threshold at which soil microorganisms become functionally P-limited is unclear because of soil acidity effect on P availability. We reason that acidic temperate hardwood forest ecosystems are, in fact, functionally P-limited, but compensation occur via soil microbial production of phosphatase enzymes. We tested this hypothesis in glaciated and unglaciated mature mixed-mesophytic forests in eastern Ohio where both soil pH and P availability had been experientially manipulated. We measured the activity of two P acquiring soil enzymes, phosphomonoesterase (PMono) and phosphodiesterase (PDi), to understand how soil acidity and available P influence microbial function. Our experimental treatments elevated ambient soil pH from below 4.5 to around 5.5 and increased readily available phosphate from 3 to ~25 mg P/kg on glaciated soils and from 0.5 to ~5 mg P/kg on unglaciated soils. The P treatment decreased the activity of PDi by 82% relative to the control on unglaciated soils, but we observed no P treatment effect on glaciated soils. A similar result was observed for PMono. Soil pH, alone, did not significantly influence enzyme activities. Results suggest that soil microorganisms are more likely to be P-limited in older unglaciated soils. However, dramatically higher phosphatase activity in response to very low P availability suggests that an underlying ecosystem P limitation can be ameliorated by soil microbial community dynamics. This mechanism may be more important for older, unglaciated soils that have already crossed a pedogenic threshold where P availability influences ecosystem and microbial function.

  17. Microstructural Effects of Sulphate Attack in Sustainable Grouts for Micropiles.

    PubMed

    Ortega Álvarez, José Marcos; Esteban Pérez, María Dolores; Rodríguez Escribano, Raúl Rubén; Pastor Navarro, José Luís; Sánchez Martín, Isidro

    2016-11-08

    Nowadays, the use of micropiles has undergone a great development. In general, they are made with cement grout, reinforced with steel tubing. In Spain, these grouts are prepared using OPC, although the standards do not forbid the use of other cements, like sustainable ones. Micropiles are in contact with soils and groundwater, in which the presence of sulphates is common. Their deleterious effects firstly affect to the microstructure. Then, the aim of this research is to study the effects of sulphate attack in the microstructure of micropiles grouts, prepared with OPC, fly ash and slag commercial cements, compared to their behaviour when they are exposed to an optimum hardening condition. The microstructure evolution has been studied with the non-destructive impedance spectroscopy technique, which has never been used for detecting the effects of sulphate attack when slag and fly ash cements are used. Its results have been contrasted with mercury intrusion porosimetry and "Wenner" resistivity ones. The 28-day compressive strength of grouts has been also determined. The results of microstructure characterization techniques are in agreement, although impedance spectroscopy is the most sensitive for following the changes in the porous network of grouts. The results showed that micropiles made using fly ash and slag cements could have a good performance in contact with aggressive sodium sulphate media, even better than OPC ones.

  18. Microstructural Effects of Sulphate Attack in Sustainable Grouts for Micropiles

    PubMed Central

    Ortega Álvarez, José Marcos; Esteban Pérez, María Dolores; Rodríguez Escribano, Raúl Rubén; Pastor Navarro, José Luís; Sánchez Martín, Isidro

    2016-01-01

    Nowadays, the use of micropiles has undergone a great development. In general, they are made with cement grout, reinforced with steel tubing. In Spain, these grouts are prepared using OPC, although the standards do not forbid the use of other cements, like sustainable ones. Micropiles are in contact with soils and groundwater, in which the presence of sulphates is common. Their deleterious effects firstly affect to the microstructure. Then, the aim of this research is to study the effects of sulphate attack in the microstructure of micropiles grouts, prepared with OPC, fly ash and slag commercial cements, compared to their behaviour when they are exposed to an optimum hardening condition. The microstructure evolution has been studied with the non-destructive impedance spectroscopy technique, which has never been used for detecting the effects of sulphate attack when slag and fly ash cements are used. Its results have been contrasted with mercury intrusion porosimetry and “Wenner” resistivity ones. The 28-day compressive strength of grouts has been also determined. The results of microstructure characterization techniques are in agreement, although impedance spectroscopy is the most sensitive for following the changes in the porous network of grouts. The results showed that micropiles made using fly ash and slag cements could have a good performance in contact with aggressive sodium sulphate media, even better than OPC ones. PMID:28774026

  19. Extraction of rare earth elements from a contaminated cropland soil using nitric acid, citric acid, and EDTA.

    PubMed

    Tang, Hailong; Shuai, Weitao; Wang, Xiaojing; Liu, Yangsheng

    2017-08-01

    Rare earth elements (REEs) contamination to the surrounding soil has increased the concerns of health risk to the local residents. Soil washing was first attempted in our study to remediate REEs-contaminated cropland soil using nitric acid, citric acid, and ethylene diamine tetraacetic acid (EDTA) for soil decontamination and possible recovery of REEs. The extraction time, washing agent concentration, and pH value of the washing solution were optimized. The sequential extraction analysis proposed by Tessier was adopted to study the speciation changes of the REEs before and after soil washing. The extract containing citric acid was dried to obtain solid for the X-ray fluorescence (XRF) analysis. The results revealed that the optimal extraction time was 72 h, and the REEs extraction efficiency increased as the agent concentration increased from 0.01 to 0.1 mol/L. EDTA was efficient to extract REEs over a wide range of pH values, while citric acid was around pH 6.0. Under optimized conditions, the average extraction efficiencies of the major REEs in the contaminated soil were 70.96%, 64.38%, and 62.12% by EDTA, nitric acid, and citric acid, respectively. The sequential extraction analyses revealed that most soil-bounded REEs were mobilized or extracted except for those in the residual fraction. Under a comprehensive consideration of the extraction efficiency and the environmental impact, citric acid was recommended as the most suitable agent for extraction of the REEs from the contaminated cropland soils. The XRF analysis revealed that Mn, Al, Si, Pb, Fe, and REEs were the major elements in the extract indicating a possibile recovery of the REEs.

  20. Sustainable Soil Washing: Shredded Card Filtration of Potentially Toxic Elements after Leaching from Soil Using Organic Acid Solutions

    PubMed Central

    Ash, Christopher; Drábek, Ondřej; Tejnecký, Václav; Jehlička, Jan; Michon, Ninon; Borůvka, Luboš

    2016-01-01

    Shredded card (SC) was assessed for use as a sorbent of potentially toxic elements (PTE) carried from contaminated soil in various leachates (oxalic acid, formic acid, CaCl2, water). We further assessed SC for retention of PTE, using acidified water (pH 3.4). Vertical columns and a peristaltic pump were used to leach PTE from soils (O and A/B horizons) before passing through SC. Sorption onto SC was studied by comparing leachates, and by monitoring total PTE contents on SC before and after leaching. SC buffers against acidic soil conditions that promote metals solubility; considerable increases in solution pH (+4.49) were observed. Greatest differences in solution PTE content after leaching with/without SC occurred for Pb. In oxalic acid, As, Cd, Pb showed a high level of sorption (25, 15, and 58x more of the respective PTE in leachates without SC). In formic acid, Pb sorption was highly efficient (219x more Pb in leachate without SC). In water, only Pb showed high sorption (191x more Pb in leachate without SC). In desorption experiments, release of PTE from SC varied according to the source of PTE (organic/mineral soil), and type of solvent used. Arsenic was the PTE most readily leached in desorption experiments. Low As sorption from water was followed by fast release (70% As released from SC). A high rate of Cd sorption from organic acid solutions was followed by strong retention (~12% Cd desorption). SC also retained Pb after sorption from water, with subsequent losses of ≤8.5% of total bound Pb. The proposed use of this material is for the filtration of PTE from extract solution following soil washing. Low-molecular-mass organic acids offer a less destructive, biodegradable alternative to strong inorganic acids for soil washing. PMID:26900684

  1. Sustainable Soil Washing: Shredded Card Filtration of Potentially Toxic Elements after Leaching from Soil Using Organic Acid Solutions.

    PubMed

    Ash, Christopher; Drábek, Ondřej; Tejnecký, Václav; Jehlička, Jan; Michon, Ninon; Borůvka, Luboš

    2016-01-01

    Shredded card (SC) was assessed for use as a sorbent of potentially toxic elements (PTE) carried from contaminated soil in various leachates (oxalic acid, formic acid, CaCl2, water). We further assessed SC for retention of PTE, using acidified water (pH 3.4). Vertical columns and a peristaltic pump were used to leach PTE from soils (O and A/B horizons) before passing through SC. Sorption onto SC was studied by comparing leachates, and by monitoring total PTE contents on SC before and after leaching. SC buffers against acidic soil conditions that promote metals solubility; considerable increases in solution pH (+4.49) were observed. Greatest differences in solution PTE content after leaching with/without SC occurred for Pb. In oxalic acid, As, Cd, Pb showed a high level of sorption (25, 15, and 58x more of the respective PTE in leachates without SC). In formic acid, Pb sorption was highly efficient (219x more Pb in leachate without SC). In water, only Pb showed high sorption (191x more Pb in leachate without SC). In desorption experiments, release of PTE from SC varied according to the source of PTE (organic/mineral soil), and type of solvent used. Arsenic was the PTE most readily leached in desorption experiments. Low As sorption from water was followed by fast release (70% As released from SC). A high rate of Cd sorption from organic acid solutions was followed by strong retention (~12% Cd desorption). SC also retained Pb after sorption from water, with subsequent losses of ≤8.5% of total bound Pb. The proposed use of this material is for the filtration of PTE from extract solution following soil washing. Low-molecular-mass organic acids offer a less destructive, biodegradable alternative to strong inorganic acids for soil washing.

  2. An investigation of inorganic antimony species and antimony associated with soil humic acid molar mass fractions in contaminated soils.

    PubMed

    Steely, Sarah; Amarasiriwardena, Dulasiri; Xing, Baoshan

    2007-07-01

    The presence of antimony compounds is often suspected in the soil of apple orchards contaminated with lead arsenate pesticide and in the soil of shooting ranges. Nitric acid (1M) extractable Sb from the shooting range (8300 microg kg(-1)) and the apple orchard (69 microg kg(-1)) had considerably higher surface Sb levels than the control site (<1.5 microg kg(-1)), and Sb was confined to the top approximately 30 cm soil layer. Sb(V) was the principal species in the shooting range and the apple orchard surface soils. Size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) analysis of humic acids isolated from the two contaminated soils demonstrated that Sb has complexed to humic acid molar mass fractions. The results also indicate that humic acids have the ability to arrest the mobility of Sb through soils and would be beneficial in converting Sb(III) to a less toxic species, Sb(V), in contaminated areas.

  3. Copper and zinc adsorption by softwood and hardwood biochars under elevated sulphate-induced salinity and acidic pH conditions.

    PubMed

    Jiang, Shasha; Huang, Longbin; Nguyen, Tuan A H; Ok, Yong Sik; Rudolph, Victor; Yang, Hong; Zhang, Dongke

    2016-01-01

    Biochar adsorption may lower concentrations of soluble metals in pore water of sulphidic Cu/Pb-Zn mine tailings. Unlike soil, high levels of salinity and soluble cations are present in tailing pore water, which may affect biochar adsorption of metals from solution. In the present study, removal of soluble copper (Cu) and zinc (Zn) ions by soft- (pine) and hard-wood (jarrah) biochars pyrolysed at high temperature (about 700 °C) was evaluated under typical ranges of pH and salinity conditions resembling those in pore water of sulphidic tailings, prior to their direct application into the tailings. Surface alkalinity, cation exchange capacity, and negative surface charge of biochars affected Cu and Zn adsorption capacities. Quantitative comparisons were provided by fitting the adsorption equilibrium data with either the homogeneous or heterogeneous surface adsorption models (i.e. Langmuir and Freundlich, respectively). Accordingly, the jarrah biochar showed higher Cu and Zn adsorption capacity (Qmax=4.39 and 2.31 mg/g, respectively) than the softwood pine biochar (Qmax=1.47 and 1.00 mg/g). Copper and Zn adsorption by the biochars was favoured by high pH conditions under which they carried more negative charges and Cu and Zn ions were predicted undergoing hydrolysis and polymerization. Within the tested range, salinity had relatively weak effects on the adsorption, which perhaps influenced the surface charge and induced competition for negative charged sites between Na(+) and exchangeable Ca(2+) and/or heavy metal ions. Large amounts of waste wood/timber at many mine sites present a cost-effective opportunity to produce biochars for remediation of sulphidic tailings and seepage water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Electrochemical studies of zinc nickel codeposition in sulphate bath

    NASA Astrophysics Data System (ADS)

    Abou-Krisha, Mortaga M.

    2005-11-01

    The electrodeposition of Zn-Ni alloys from a sulphate bath was studied under different conditions. The bath had the composition 0.40 M sodium sulphate, 0.01 M sulphuric acid, 0.16 M boric acid, 0.20 M zinc sulphate and 0.20 M nickel sulphate. It is found that the plating bath temperature has a great effect on the cyclic voltammograms, galvanostatic measurements during electrodeposition, and consequently linear polarization resistance for corrosion study and the alloy composition. Under the examined conditions, the electrodeposition of the alloys was of anomalous type. X-ray diffraction measurements revealed that the alloys consisted of the δ-phase (Ni 3Zn 22) or a mixture of the two phases δ and γ (Ni 5Zn 21). The comparison between Ni deposition and Zn-Ni codeposition revealed that the remarkable inhibition of Ni deposition takes place due to the presence of Zn 2+ in the plating bath. The Ni deposition starts at -0.85 V in the bath of Ni deposition only, but the deposition starts at more negative potentials in the codeposition bath although the concentration of Ni 2+ is the same in the both baths.

  5. Identifying sources of acidity and spatial distribution of acid sulfate soils in the Anglesea River catchment, southern Australia

    NASA Astrophysics Data System (ADS)

    Wong, Vanessa; Yau, Chin; Kennedy, David

    2015-04-01

    Globally, coastal and estuarine floodplains are frequently underlain by sulfidic sediments. When exposed to oxygen, sulfidic sediments oxidise to form acid sulfate soils, adversely impacting on floodplain health and adjacent aquatic ecoystems. In eastern Australia, our understanding of the formation of these coastal and estuarine floodplains, and hence, spatial distribution of acid sulfate soils, is relatively well established. These soils have largely formed as a result of sedimentation of coastal river valleys approximately 6000 years BP when sea levels were one to two metres higher. However, our understanding of the evolution of estuarine systems and acid sulfate soil formation, and hence, distribution, in southern Australia remains limited. The Anglesea River, in southern Australia, is subjected to frequent episodes of poor water quality and low pH resulting in closure of the river and, in extreme cases, large fish kill events. This region is heavily reliant on tourism and host to a number of iconic features, including the Great Ocean Road and Twelve Apostles. Poor water quality has been linked to acid leakage from mining activities and Tertiary-aged coal seams, peat swamps and acid sulfate soils in the region. However, our understanding of the sources of acidity and distribution of acid sulfate soils in this region remains poor. In this study, four sites on the Anglesea River floodplain were sampled, representative of the main vegetation communities. Peat swamps and intertidal marshes were both significant sources of acidity on the floodplain in the lower catchment. However, acid neutralising capacity provided by carbonate sands suggests that there are additional sources of acidity higher in the catchment. This pilot study has highlighted the complexity in the links between the floodplain, upper catchment and waterways with further research required to understand these links for targeted acid management strategies.

  6. Metal mobilization from metallurgical wastes by soil organic acids.

    PubMed

    Potysz, Anna; Grybos, Malgorzata; Kierczak, Jakub; Guibaud, Gilles; Fondaneche, Patrice; Lens, Piet N L; van Hullebusch, Eric D

    2017-07-01

    Three types of Cu-slags differing in chemical and mineralogical composition (historical, shaft furnace, and granulated slags) and a matte from a lead recovery process were studied with respect to their susceptibility to release Cu, Zn and Pb upon exposure to organic acids commonly encountered in soil environments. Leaching experiments (24-960 h) were conducted with: i) humic acid (20 mg/L) at pH t0 = 4.4, ii) fulvic acid (20 mg/L) at pH t0 = 4.4, iii) an artificial root exudates (ARE) (17.4 g/L) solution at pH t0 = 4.4, iv) ARE solution at pH t0 = 2.9 and v) ultrapure water (pH t0 = 5.6). The results demonstrated that the ARE contribute the most to the mobilization of metals from all the wastes analyzed, regardless of the initial pH of the solution. For example, up to 14%, 30%, 24% and 5% of Cu is released within 960 h from historical, shaft furnace, granulated slags and lead matte, respectively, when exposed to the artificial root exudates solution (pH 2.9). Humic and fulvic acids were found to have a higher impact on granulated and shaft furnace slags as compared to the ultrapure water control and increased the release of metals by a factor up to 37.5 (Pb) and 20.5 (Cu) for granulated and shaft furnace slags, respectively. Humic and fulvic acids amplified the mobilization of metals by a maximal factor of 13.6 (Pb) and 12.1 (Pb) for historical slag and lead matte, respectively. The studied organic compounds contributed to different release rates of metallic contaminants from individual metallurgical wastes under the conditions tested. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Seasonal changes of principal anions contents and other soil properties in acidified forest soils

    NASA Astrophysics Data System (ADS)

    Drabek, O.; Tejnecky, V.; Bradová, M.; Němeček, K.; Šebek, O.; Zenáhlíková, J.; Boruvka, L.

    2011-12-01

    Acidification of forest soil is a natural degradation process enhanced by anthropogenic activities. The depositions of principal inorganic anions are the main external acidity inputs to forest ecosystems. The aim of the study was to describe seasonal changes of sulphate and nitrate behaviour in soils and influence of their depositions on the selected forest soil properties. The following soil properties were investigated: soil pH, DOC, selected elements contents and Al species content. The Jizera Mountains area (Czech Republic) was chosen as a representative soil mountainous ecosystem affected by acidification. Soil and precipitation samples were collected at monthly intervals from April to October during the years 2008-2010 under beech and spruce stands. Prevailing soil types were classified as Alumic Cambisols under beech and Entic Podzols under spruce stands (according to FAO classification). Soil samples were collected from surface fermentation (F) and humified (H) organic horizons and subsurface B horizons (cambic or spodic). The collected soil samples were analyzed immediately in a "fresh" state. Unsieved fresh samples were extracted by deionised water and content of anions (sulphate, nitrate, chloride and fluoride) in these extracts were determined by ion-exchange chromatography (IC); the Al speciation was performed by means of HPLC/IC. The extracts were also used for determination of main elements content (Al, Ca, Mg, Ca, Na and Fe) by means of ICP-OES. Content of anions and main elements content, pH and conductivity were determined also in the precipitation samples (throughfall, stemflow and bulk). Statistically significant differences in distributions of monitored anions between the tested soil horizons were observed. The highest content of sulphate was determined in F and B horizons. On the contrary, contents of nitrate were highest in F horizons and lowest in B horizons. Higher annual variability in the investigated characteristics was proven for

  8. Emission of nitrous acid from soil and biological soil crusts as a major source of atmospheric HONO on Cyprus

    NASA Astrophysics Data System (ADS)

    Meusel, Hannah; Tamm, Alexandra; Wu, Dianming; Kuhn, Uwe; Leifke, Anna-Lena; Weber, Bettina; Su, Hang; Lelieveld, Jos; Hoffmann, Thorsten; Pöschl, Ulrich; Cheng, Yafang

    2017-04-01

    Elucidation of the sources and atmospheric chemistry of nitrous acid (HONO) is highly relevant, as HONO is an important precursor of OH radicals. Up to 30% of the OH budget are formed by photolysis of HONO, whereas major fractions of HONO measured in the field derive from yet unidentified sources. Heterogeneous conversion of nitrogen dioxide (NO2) to HONO on a variety of surfaces (soot, humic acid aerosol) is assumed to be a major HONO source (Stemmler et al., 2007, Ammann et al., 1998). In rural regions, however, NO2 concentrations were found to be too low to explain observed HONO concentrations, as e.g., in the case of a recent field study on the Mediterranean island of Cyprus (Meusel et al., 2016). In this study a good correlation between missing sources of HONO and nitrogen oxide (NO) was found indicating a common origin of both reactive nitrogen compounds. Simultaneous emission of HONO and NO from soil was reported earlier (Oswald et al., 2013), and enhanced emission rates were found when soil was covered by biological soil crusts in arid and semi-arid ecosystems (Weber et al., 2015). In the present study we measured HONO and NO emissions of 43 soil and soil crust samples from Cyprus during full wetting and drying cycles under controlled laboratory conditions by means of a dynamic chamber system. The observed range of HONO and NO emissions was in agreement with earlier studies, but unlike the study of Weber et al. (2015), we found highest emission from bare soil, followed by soil covered by light and dark cyanobacteria-dominated biological soil crusts. Emission rates correlated well with the nitrite and nitrate contents of soil and biological soil crust samples, and higher nutrient contents of bare soil samples, as compared to the previous biological soil crust study, explain the higher bare soil emissions. Integrating the emission rates of bare soil and the different types of biological soil crusts, based on their local relative abundance, the calculated

  9. Ammonia-oxidizing activity and microbial community structure in acid tea (Camellia sinensis) orchard soil

    NASA Astrophysics Data System (ADS)

    Okamura, K.; Takanashi, A.; Yamada, T.; Hiraishi, A.

    2012-03-01

    The purpose of this study was to determine the ammonia-oxidizing activity and the phylogentic composition of microorganisms involved in acid tea (Camellia sinensis) orchard soil. All soil samples were collected from three sites located in Tahara and Toyohashi, Aichi Prefecture, Japan. The potential nitrification rate (PNR) was measured by the chlorate inhibition method. The soil pH of tea orchards studied ranged from 2.78 to 4.84, differing significantly from sample to sample, whereas that of meadow and unplanted fields ranged from 5.78 to 6.35. The PNR ranged from 0.050 to 0.193 μg NO2--Ng-1 h-1 and were positively correlated with the soil pH (r2 = 0.382, p<0.001). Bulk DNA was extracted from a tea orchard soil (pH 4.8; PNR, 0.078 μg NO2--Ng-1 h-1) and subjected to PCR-aided clone library analyses targeting archaeal and bacterial amoA genes. The detected archaeal clones separated from the cluster of the 'Soil clones' and tightly clustered with the clones originating from other acidic soil environments including the Chinese tea orchard soil. These results suggest that the specific archaeal populations dominate as the ammonia oxidizers in acid tea-orchard soils and possibly other acid soils, independent of geographic locations, which results from the adaptation to specific ecological niches.

  10. Effects of simulated acid rain on microbial characteristics in a lateritic red soil.

    PubMed

    Xu, Hua-qin; Zhang, Jia-en; Ouyang, Ying; Lin, Ling; Quan, Guo-ming; Zhao, Ben-liang; Yu, Jia-yu

    2015-11-01

    A laboratory experiment was performed to examine the impact of simulated acid rain (SAR) on nutrient leaching, microbial biomass, and microbial activities in a lateritic red soil in South China. The soil column leaching experiment was conducted over a 60-day period with the following six SAR pH treatments (levels): 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 and one control treatment (pH = 7). Compared with the control treatment, the concentrations of soil organic matter, total nitrogen, total phosphorus, total potassium, soil microbial biomass carbon (MBC), soil microbial biomass nitrogen (MBN), and average well color density (AWCD) in the Ecoplates were all significantly decreased by leaching with SAR at different pH levels. The decrease in MBC and MBN indicated that acid rain reduced the soil microbial population, while the decrease in AWCD revealed that acid rain had a negative effect on soil bacterial metabolic function. Soil basal respiration increased gradually from pH 4.0 to 7.0 but decreased dramatically from pH 2.5 to 3.0. The decrease in soil nutrient was the major reason for the change of soil microbial functions. A principal component analysis showed that the major carbon sources used by the bacteria were carbohydrates and carboxylic acids.

  11. Geochemistry of alpine soils in the Colorado Front Range, with special reference to acid deposition

    SciTech Connect

    Litaor, M.I.

    1986-01-01

    Various components of the soil in the Green Lakes Valley, Colorado Front Range, were studied to evaluate the capacity of the terrestrial system to buffer acid deposition. This investigation suggests that the soils in the study area are probably unaffected by the current loading rate of acid deposition. The existence of calcite in eolian dust and the substantial contribution of dissolved organic carbon (DOC) to the acid-neutralizing capacity maintain the pH values of the soil solutions near neutrality. Chemical and physical characteristics of the soils, such as acid neutralizing capacity (ANC), cation exchange capacity, bulk density, and water retention capacities, are highly dependent on organic carbon content. In order to determine the contribution of humic substances to the buffering capacity of a given soil, DOC and pH of the soil solutions were measured. The aluminium solubility in the soil interstitial waters is a complex phenomenon that is controlled by the concentrations of DOC, H/sub 2/SiO/sub 4/, and pH. The soil water pH and concentrations of SO/sub 4//sup 2 -/ do not correlate with aluminum concentrations. The chemical equilibria of aluminum are being controlled by amorphous aluminosilicate Al(HO)/sub 3(1-x)/SiO/sub 2x/. Studies of the mineralogy and soil water chemistry comprise a useful combination in evaluating and predicting the chemical processes of a given soil environment.

  12. Bioaccumulation of perfluoroalkyl acids by earthworms (Eisenia fetida) exposed to contaminated soils.

    PubMed

    Rich, Courtney D; Blaine, Andrea C; Hundal, Lakhwinder; Higgins, Christopher P

    2015-01-20

    The presence of perfluoroalkyl acids (PFAAs) in biosolids-amended and aqueous film-forming foam (AFFF)-impacted soils results in two potential pathways for movement of these environmental contaminants into terrestrial foodwebs. Uptake of PFAAs by earthworms (Eisenia fetida) exposed to unspiked soils with varying levels of PFAAs (a control soil, an industrially impacted biosolids-amended soil, a municipal biosolids-amended soil, and two AFFF-impacted soils) was measured. Standard 28 day exposure experiments were conducted in each soil, and measurements taken at additional time points in the municipal soil were used to model the kinetics of uptake. Uptake and elimination rates and modeling suggested that steady state bioaccumulation was reached within 28 days of exposure for all PFAAs. The highest concentrations in the earthworms were for perfluorooctane sulfonate (PFOS) in the AFFF-impacted Soil A (2160 ng/g) and perfluorododecanoate (PFDoA) in the industrially impacted soil (737 ng/g). Wet-weight (ww) and organic carbon (OC)-based biota soil accumulation factors (BSAFs) for the earthworms were calculated after 28 days of exposure for all five soils. The highest BSAF in the industrially impacted soil was for PFDoA (0.42 goc/gww,worm). Bioaccumulation factors (BAFs, dry-weight-basis, dw) were also calculated at 28 days for each of the soils. With the exception of the control soil and perfluorodecanoate (PFDA) in the industrially impacted soil, all BAF values were above unity, with the highest being for perfluorohexanesulfonate (PFHxS) in the AFFF-impacted Soil A (139 gdw,soil/gdw,worm). BSAFs and BAFs increased with increasing chain length for the perfluorocarboxylates (PFCAs) and decreased with increasing chain length for the perfluoroalkyl sulfonates (PFSAs). The results indicate that PFAA bioaccumulation into earthworms depends on soil concentrations, soil characteristics, analyte, and duration of exposure, and that accumulation into earthworms may be a potential

  13. 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.

  14. Effects of acidic and neutral biochars on properties and cadmium retention of soils.

    PubMed

    Qi, Fangjie; Dong, Zhaomin; Lamb, Dane; Naidu, Ravi; Bolan, Nanthi S; Ok, Yong Sik; Liu, Cuixia; Khan, Naser; Johir, M A H; Semple, Kirk T

    2017-08-01

    In this study, an acidic biochar and a neutral biochar were applied at 5 wt% into two soils for an 11-month incubation experiment. One Ferrosol soil (Ba) was slightly acidic with low organic matter and the other Dermosol soil (Mt) was slightly alkaline with high organic matter. The acidic (pH = 3.25) wood shaving (WS) biochar had no marked impact on nutrient levels, cation exchange capacity (CEC), pH and acid neutralization capacity (ANC) of either soil. By contrast, the neutral (pH = 7.00) chicken litter (CL) biochar significantly increased major soluble nutrients, pH, ANC of soil Ba. In terms of C storage, 87.9% and 69.5% WS biochar-C can be sequestrated as TOC by soil Ba and Mt, respectively, whereas only 24.0% of CL biochar-C stored in soil Ba and negligible amount in Mt as TOC. Biochars did not have significant effects on soil sorption capacity and sorption reversibility except that CL biochar increased sorption of soil Ba by around 25.4% and decreased desorption by around 50.0%. Overall, the studied acidic C rich WS biochar held little agricultural or remedial values but was favourable for C sequestration. The neutral mineral rich CL biochar may provide short-term agricultural benefit and certain sorption capacities of lower sorption capacity soils, but may be unlikely to result in heightened C sequestration in soils. This is the first study comprehensively examining functions of acidic and neutral biochars for their benefits as a soil amendment and suggests the importance of pre-testing biochars for target purposes prior to their large scale production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Remediation of Pb-contaminated soils by washing with hydrochloric acid and subsequent immobilization with calcite and allophanic soil.

    PubMed

    Isoyama, Masahiro; Wada, Shin-Ichiro

    2007-05-17

    Removal of heavy metals from contaminated soil is not popular because of its high cost. Reducing the bioaccessible heavy metals content to an allowable level by washing with inorganic acids and subsequent immobilization of remained metals may be a low cost option for soil remediation. The applicability of this combined treatment was investigated using three different types of soil, a kaolinitic, a smectitic and an allophanic soil, which were artificially contaminated with Pb. The effectiveness of the treatment was evaluated using two main criteria: (i) reduction of the HCl extractable Pb (bioaccessible Pb) below 150 mg kg(-1), reduction of water extractable Pb below the concentration of 0.01 mg L(-1). These values correspond to allowable levels suggested by the Japanese Ministry of Environment. The soils were washed batch-wise at a solution to soil ratio of 5 L kg(-1) successively with 1 mol L(-1) HCl and 0.1 mol L(-1) CaCl(2) solutions. The two solutions were separated by filtration from one batch and reused for washing the next batch of soil without processing. The Pb concentration in the solutions increased after repeated use and removal efficiency gradually declined. The efficiency of the treatment was highly dependent on the type of soil. In the kaolinitic soil, HCl extractable Pb content of the soil from the first batch was about 50 mg kg(-1) and it exceeded 150 mg kg(-1) in that from sixth batch. But the combined soils from 1st to 10th batches gave bioaccessible Pb content barely below 150 mg kg(-1). For the smectitic soil having higher cation exchange capacity, the acceptable number of times of reuse was estimated to be 4. For the allophanic soil, treatment with the HCl solution was efficient only for the first batch of the soil, and the reuse of the acid solution was found to be ineffective. The application of 50 g kg(-1) of calcite or slacked lime was effective for reducing the water extractable Pb content. To keep soil pH near neutral and secure long

  16. [Effects of soil acidity on Pinus resinosa seedlings photosynthesis and chlorophyll fluorescence].

    PubMed

    Liu, Shuang; Wang, Qing-cheng; Liu, Ya-li; Tian, Yu-ming; Sun, Jing; Xu, Jing

    2009-12-01

    Red pine (Pinus resinosa) is one of the most important tree species for timber plantation in North America, and preliminary success has been achieved in its introduction to the mountainous area of Northeast China since 2004. In order to expand its growth area in other parts of Northeast China, a pot experiment was conducted to study the adaptability of this tree species to varying soil acidity. P. resinosa seedlings were grown in soils with different acidity (pH = 4.5, 5.5, 6.5, 7.5, and 8.0) to test the responses of their photosynthesis and chlorophyll fluorescence parameters to soil pH levels, and the appropriate soil acidity was evaluated. Dramatic responses in chlorophyll a and b contents, Pn and chlorophyll fluorescence parameters (Fo, Fm, Fv, Fv/Fm, and phi(PS II)) were detected under different soil acidity (P < 0.05), with the highest chlorophyll content and Pn under soil pH 5.5, and significantly lower chlorophyll content and Pn under soil pH 7.5 and 8.0. The chlorophyll content and Pn were 41% and 50%, and 61% and 88% higher under soil pH 5.5 than under soil pH 7.5 and 8.0. The seedlings had a significant photosynthetic inhibition under soil pH 7.5 and 8.0, but the highest Fv/Fm and phi (PS II) under soil pH 5.5. Comparing with those under soil pH 7.5 and 8.0, the Fv/Fm and phi (PS II) under soil pH 5.5 were 8% and 12%, and 22% and 35% higher, respectively. It was suggested that soil pH 5.5 was most appropriate for P. resinosa growth.

  17. The effect of acidity on the distribution and symbiotic efficiency of rhizobia in Lithuanian soils

    NASA Astrophysics Data System (ADS)

    Lapinskas, E. B.

    2007-04-01

    The distribution and symbiotic efficiency of nodule bacteria Rhizobium leguminosarum_bv. trifolii F., Sinorhizobium meliloti D., Rhizobium galegae L., and Rhizobium leguminosarum bv. viciae F. in Lithuanian soils as dependent on the soil acidity were studied in the long-term field, pot, and laboratory experiments. The critical and optimal pH values controlling the distribution of rhizobia and the symbiotic nitrogen fixation were determined for every bacterial species. The relationship was found between the soil pH and the nitrogen-fixing capacity of rhizobia. A positive effect of liming of acid soils in combination with inoculation of legumes on the efficiency of symbiotic nitrogen fixation was demonstrated.

  18. An acid-tolerant ammonia-oxidizing γ-proteobacterium from soil.

    PubMed

    Hayatsu, Masahito; Tago, Kanako; Uchiyama, Ikuo; Toyoda, Atsushi; Wang, Yong; Shimomura, Yumi; Okubo, Takashi; Kurisu, Futoshi; Hirono, Yuhei; Nonaka, Kunihiko; Akiyama, Hiroko; Itoh, Takehiko; Takami, Hideto

    2017-01-10

    Nitrification, the microbial oxidation of ammonia to nitrate via nitrite, occurs in a wide range of acidic soils. However, the ammonia-oxidizing bacteria (AOB) that have been isolated from soil to date are acid-sensitive. Here we report the isolation and characterization of an acid-adapted AOB from an acidic agricultural soil. The isolated AOB, strain TAO100, is classified within the Gammaproteobacteria based on phylogenetic characteristics. TAO100 can grow in the pH range of 5-7.5 and survive in highly acidic conditions until pH 2 by forming cell aggregates. Whereas all known gammaproteobacterial AOB (γ-AOB) species, which have been isolated from marine and saline aquatic environments, are halophiles, TAO100 is not phenotypically halophilic. Thus, TAO100 represents the first soil-originated and non-halophilic γ-AOB. The TAO100 genome is considerably smaller than those of other γ-AOB and lacks several genes associated with salt tolerance which are unnecessary for survival in soil. The ammonia monooxygenase subunit A gene of TAO100 and its transcript are higher in abundance than those of ammonia-oxidizing archaea and betaproteobacterial AOB in the strongly acidic soil. These results indicate that TAO100 plays an important role in the nitrification of acidic soils. Based on these results, we propose TAO100 as a novel species of a new genus, Candidatus Nitrosoglobus terrae.The ISME Journal advance online publication, 10 January 2017; doi:10.1038/ismej.2016.191.

  19. Anti-inflammatory effects of the selective phosphodiesterase 3 inhibitor, cilostazol, and antioxidants, enzymatically-modified isoquercitrin and α-lipoic acid, reduce dextran sulphate sodium-induced colorectal mucosal injury in mice.

    PubMed

    Kangawa, Yumi; Yoshida, Toshinori; Abe, Hajime; Seto, Yoshiki; Miyashita, Taishi; Nakamura, Michi; Kihara, Tohru; Hayashi, Shim-Mo; Shibutani, Makoto

    2017-04-04

    Developing effective treatments and preventing inflammatory bowel disease (IBD) are urgent challenges in improving patients' health. It has been suggested that platelet activation and reactive oxidative species generation are involved in the pathogenesis of IBD. We examined the inhibitory effects of a selective phosphodiesterase-3 inhibitor, cilostazol (CZ), and two antioxidants, enzymatically modified isoquercitrin (EMIQ) and α-lipoic acid (ALA), against dextran sulphate sodium (DSS)-induced colitis. BALB/c mice were treated with 0.3% CZ, 1.5% EMIQ, and 0.2% ALA in their feed. Colitis was induced by administering 5% DSS in drinking water for 8days. The inhibitory effects of these substances were evaluated by measuring relevant clinical symptoms (faecal blood, diarrhoea, and body weight loss), colon length, plasma cytokine and chemokine levels, whole genome gene expression, and histopathology. Diarrhoea was suppressed by each treatment, while CZ prevented shortening of the colon length. All treatment groups exhibited decreased plasma levels of interleukin (IL)-6 and tumour necrosis factor (TNF)-α compared with the DSS group. Microarray analysis showed that cell adhesion, cytoskeleton regulation, cell proliferation, and apoptosis, which might be related to inflammatory cell infiltration and mucosal healing, were affected in all the groups. DSS-induced mucosal injuries such as mucosal loss, submucosal oedema, and inflammatory cell infiltration in the distal colon were prevented by CZ or antioxidant treatment. These results suggest that anti-inflammatory effects of these agents reduced DSS-induced mucosal injuries in mice and, therefore, may provide therapeutic benefits in IBD.

  20. Hydraulic conductivity study of compacted clay soils used as landfill liners for an acidic waste.

    PubMed

    Hamdi, Noureddine; Srasra, Ezzeddine

    2013-01-01

    Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5 × 10(-10), 2.08 × 10(-9) and 6.8 × 10(-10)m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050 kg/m(3)). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200 days) using acidic waste solution (pH=2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050 kg/m(3)) are cracked after 60 and 20 days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity.

  1. Persistent episodic acidification of streams linked to acid rain effects on soil

    USGS Publications Warehouse

    Lawrence, G.B.

    2002-01-01

    Episodic acidification of streams, identified in the late 1980s as one of the most significant environmental problems caused by acidic deposition, had not been evaluated since the early 1990s despite decreasing levels of acidic deposition over the past decade. This analysis indicates that episodic acidification of streams in upland regions in the northeastern United States persists, and is likely to be much more widespread than chronic acidification. Depletion of exchangeable Ca in the mineral soil has decreased the neutralization capacity of soils and increased the role of the surface organic horizon in the neutralization of acidic soil water during episodes. Increased accumulation of N and S in the forest floor from decades of acidic deposition will delay the recovery of soil base status, and therefore, the elimination of acidic episodes, which is anticipated from decreasing emissions.

  2. Persistent episodic acidification of streams linked to acid rain effects on soil

    NASA Astrophysics Data System (ADS)

    Lawrence, G. B.

    Episodic acidification of streams, identified in the late 1980s as one of the most significant environmental problems caused by acidic deposition, had not been evaluated since the early 1990s despite decreasing levels of acidic deposition over the past decade. This analysis indicates that episodic acidification of streams in upland regions in the northeastern United States persists, and is likely to be much more widespread than chronic acidification. Depletion of exchangeable Ca in the mineral soil has decreased the neutralization capacity of soils and increased the role of the surface organic horizon in the neutralization of acidic soil water during episodes. Increased accumulation of N and S in the forest floor from decades of acidic deposition will delay the recovery of soil base status, and therefore, the elimination of acidic episodes, which is anticipated from decreasing emissions.

  3. Effects of dicyandiamide and dolomite application on N2O emission from an acidic soil.

    PubMed

    Shaaban, Muhammad; Wu, Yupeng; Peng, Qi-an; Lin, Shan; Mo, Yongliang; Wu, Lei; Hu, Ronggui; Zhou, Wei

    2016-04-01

    Soil acidification is a major problem for sustainable agriculture since it limits productivity of several crops. Liming is usually adopted to ameliorate soil acidity that can trigger soil processes such as nitrification, denitrification, and loss of nitrogen (N) as nitrous oxide (N2O) emissions. The loss of N following liming of acidic soils can be controlled by nitrification inhibitors (such as dicyandiamide). However, effects of nitrification inhibitors following liming of acidic soils are not well understood so far. Here, we conducted a laboratory study using an acidic soil to examine the effects of dolomite and dicyandiamide (DCD) application on N2O emissions. Three levels of DCD (0, 10, and 20 mg kg(-1); DCD0, DCD10, and DCD20, respectively) were applied to the acidic soil under two levels of dolomite (0 and 1 g kg(-1)) which were further treated with two levels of N fertilizer (0 and 200 mg N kg(-1)). Results showed that N2O emissions were highest at low soil pH levels in fertilizer-treated soil without application of DCD and dolomite. Application of DCD and dolomite significantly (P ≤ 0.001) reduced N2O emissions through decreasing rates of NH4 (+)-N oxidation and increasing soil pH, respectively. Total N2O emissions were reduced by 44 and 13% in DCD20 and dolomite alone treatments, respectively, while DCD20 + dolomite reduced N2O emissions by 54% when compared with DCD0 treatment. The present study suggests that application of DCD and dolomite to acidic soils can mitigate N2O emissions.

  4. The sulphated carbohydrate-protein linkage region isolated from chondroitin 4-sulphate chains of inter-alpha-trypsin inhibitor in human plasma.

    PubMed

    Yamada, S; Oyama, M; Kinugasa, H; Nakagawa, T; Kawasaki, T; Nagasawa, S; Khoo, K H; Morris, H R; Dell, A; Sugahara, K

    1995-05-01

    Inter-alpha-trypsin inhibitor (ITI) in human plasma has a unique structural architecture composed of three polypeptide chains (H1, H2 and L chains), which are linked to each other through a chondroitin 4-sulphate chain. The structure of the carbohydrate-protein linkage region of the chondroitin 4-sulphate chain attached to the L chain was investigated. The peptide-chondroitin sulphate fraction was isolated by anion-exchange chromatography after exhaustive digestion with lysyl endopeptidase and then V8 protease. The chondroitin 4-sulphate chain was released from the peptides by beta-elimination using NaB3H4 and then digested with chondroitinase ABC. These treatments resulted in a single 3H-labelled hexasaccharide alditol fraction derived from the linkage region which had been associated with the L chain. Chemical and enzymatic analyses as well as fast-atom bombardment-mass spectrometry (FAB-MS) analysis revealed that the 3H-labelled hexasaccharide alditol had the following structure: delta HexA-alpha 1-3GalNAc(4-sulphate)beta 1-4GlcA beta 1-3Gal(4-sulphate)beta 1-3Gal beta 1-4Xyl-ol (where delta HexA is 4-deoxy-alpha-L-threo-hex-4-enepyranosyluronic acid and Xyl-ol is xylitol). The structure contained the novel 4-sulphated Gal residue, which was previously demonstrated in a linkage hexasaccharide isolated from chondroitin 4-sulphate of rat chondrosarcoma (Sugahara et al., J. Biol. Chem., 263, 10168-10174, 1988) and of whale cartilage (Sugahara et al., Eur. J. Biochem., 202, 805-811, 1991). The above disulphated hexasaccharide alditol was the only component detected in the linkage region fraction of the chondroitin 4-sulphate chain of ITI, which implies some biological significance of this novel structure.

  5. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS: DETECTION AND QUANTITATION ISSUES AT LOW CONCENTRATIONS

    EPA Science Inventory

    Methods were developed for the extraction from soil, identification, confirmation and quantitation by LC/MS/MS of trace levels of perfluorinated octanoic acid (PFOA), perfluorinated nonanoic acid (PFNA) and perfluorinated decanoic acid (PFDA). Whereas PFOA, PFNA and PFDA all can...

  6. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS: DETECTION AND QUANTITATION ISSUES AT LOW CONCENTRATIONS

    EPA Science Inventory

    Methods were developed for the extraction from soil, identification, confirmation and quantitation by LC/MS/MS of trace levels of perfluorinated octanoic acid (PFOA), perfluorinated nonanoic acid (PFNA) and perfluorinated decanoic acid (PFDA). Whereas PFOA, PFNA and PFDA all can...

  7. Alleviating aluminum toxicity in an acid sulfate soil from Peninsular Malaysia by calcium silicate application

    NASA Astrophysics Data System (ADS)

    Elisa, A. A.; Ninomiya, S.; Shamshuddin, J.; Roslan, I.

    2016-03-01

    In response to human population increase, the utilization of acid sulfate soils for rice cultivation is one option for increasing production. The main problems associated with such soils are their low pH values and their associated high content of exchangeable Al, which could be detrimental to crop growth. The application of soil amendments is one approach for mitigating this problem, and calcium silicate is an alternative soil amendment that could be used. Therefore, the main objective of this study was to ameliorate soil acidity in rice-cropped soil. The secondary objective was to study the effects of calcium silicate amendment on soil acidity, exchangeable Al, exchangeable Ca, and Si content. The soil was treated with 0, 1, 2, and 3 Mg ha-1 of calcium silicate under submerged conditions and the soil treatments were sampled every 30 days throughout an incubation period of 120 days. Application of calcium silicate induced a positive effect on soil pH and exchangeable Al; soil pH increased from 2.9 (initial) to 3.5, while exchangeable Al was reduced from 4.26 (initial) to 0.82 cmolc kg-1. Furthermore, the exchangeable Ca and Si contents increased from 1.68 (initial) to 4.94 cmolc kg-1 and from 21.21 (initial) to 81.71 mg kg-1, respectively. Therefore, it was noted that calcium silicate was effective at alleviating Al toxicity in acid sulfate, rice-cropped soil, yielding values below the critical level of 2 cmolc kg-1. In addition, application of calcium silicate showed an ameliorative effect as it increased soil pH and supplied substantial amounts of Ca and Si.

  8. Potential origin and formation for molecular components of humic acids in soils

    NASA Astrophysics Data System (ADS)

    DiDonato, Nicole; Chen, Hongmei; Waggoner, Derek; Hatcher, Patrick G.

    2016-04-01

    Soil humic acids are the base soluble/acid insoluble organic components of soil organic matter. Most of what we know about humic acids comes from studies of their bulk molecular properties or analysis of individual fractions after extraction from soils. This work attempts to better define humic acids and explain similarities and differences for several soils varying in degrees of humification using advanced molecular level techniques. Our investigation using electrospray ionization coupled to Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) and nuclear magnetic resonance spectroscopy (NMR) has given new insight into the distinctive molecular characteristics of humic acids which suggest a possible pathway for their formation. Humic acids from various ecosystems, climate regions and soil textural classes are distinguished by the presence of three predominant molecular components: lignin-like molecules, carboxyl-containing aliphatic molecules and condensed aromatic molecules that bear similarity to black carbon. Results show that humification may be linked to the relative abundance of these three types of molecules as well as the relative abundance of carboxyl groups in each molecular type. This work also demonstrates evidence for lignin as the primary source of soil organic matter, particularly condensed aromatic molecules often categorized as black carbon and is the first report of the non-pyrogenic source for these compounds in soils. We also suggest that much of the carboxyl-containing aliphatic molecules are sourced from lignin.

  9. Identification of an extended N-acetylated sequence adjacent to the protein-linkage region of fibroblast heparan sulphate.

    PubMed Central

    Lyon, M; Steward, W P; Hampson, I N; Gallagher, J T

    1987-01-01

    The distribution of N-sulphate groups within fibroblast heparan sulphate chains was investigated. The detergent-extractable heparan sulphate proteoglycan from adult human skin fibroblasts, radiolabelled with [3H]glucosamine and [35S]sulphate, was coupled to CNBr-activated Sepharose 4B. After partial depolymerization of the heparan sulphate with nitrous acid, the remaining Sepharose-bound fragments were removed by treatment with alkali. These fragments, of various sizes, but all containing an intact reducing xylose residue, were fractionated on Sephacryl S-300 and the distribution of the 3H and 35S radiolabels was analysed. A decreased degree of sulphation was observed towards the reducing termini of the chains. After complete nitrous acid hydrolysis of the Sepharose-bound proteoglycan, analysis of the proximity of N-sulphation to the reducing end revealed the existence of an extended N-acetylated sequence directly adjacent to the protein-linkage sequence. The size of this N-acetylated domain was estimated by gel filtration to be approximately eight disaccharide units. This domain appears to be highly conserved, being present in virtually all the chains derived from this proteoglycan, implying the existence of a mechanism capable of generating such a non-random sequence during the post-polymeric modification of heparan sulphate. Comparison with the corresponding situation in heparin suggests that different mechanisms regulate polymer N-sulphation in the vicinity of the protein-linkage region of these chemically related glycosaminoglycans. PMID:2954540

  10. Impact of acid effluent from Kawah Ijen crater lake on irrigated agricultural soils: Soil chemical processes and plant uptake

    NASA Astrophysics Data System (ADS)

    van Rotterdam-Los, A. M. D.; Heikens, A.; Vriend, S. P.; van Bergen, M. J.; van Gaans, P. F. M.

    2008-12-01

    Volcanogenic contamination of irrigation water, caused by effluent from the hyperacid Ijen crater lake, has severely affected the properties of agricultural soils in East Java, Indonesia. From a comparison of acidified topsoil with subsoil and with top- and subsoil in a reference area, we identified processes responsible for changes in soil and soil solution chemistry induced by acid irrigation water, with emphasis on the nutrients Ca, Mg, Fe, and Mn, and on Al, which may become phytotoxic under acid conditions in soils. Compositional data for bulk soil composition and selective extractions with 1 M KCl and 0.2 M acid ammonium oxalate are used in a mass balance approach to specify element fluxes, including uptake by rice plants. The results show that input via irrigation water has produced an increase in the total aluminum content in the affected topsoil, which is of the same order of magnitude as the increase in labile Al. High bioavailability of Al, as reflected by concentrations in KCl extracts, is consistent with elevated concentrations observed in rice plants. In contrast, and despite the high input via irrigation water, Ca and Mg concentrations have decreased in all measured soil fractions through dissolution of amorphous phases and minerals, and through competition of Al for adsorption sites on the exchange complex and plant roots. Strong leaching is also evident for Fe and especially Mn. In terms of the overall mass balance of the topsoil, plant uptake of Al, Ca, Fe, Mg and Mn is negligible. If the use of acid irrigation would be stopped and the soil pH were to increase to values above 4.5, the observed phytotoxicity of Al will be halted. However, crops may then become fully dependent on the input from irrigation water or fertilizer for essential elements, due to the previous removal from the topsoil through leaching.

  11. Massive volcanic SO(2) oxidation and sulphate aerosol deposition in Cenozoic North America.

    PubMed

    Bao, Huiming; Yu, Shaocai; Tong, Daniel Q

    2010-06-17

    Volcanic eruptions release a large amount of sulphur dioxide (SO(2)) into the atmosphere. SO(2) is oxidized to sulphate and can subsequently form sulphate aerosol, which can affect the Earth's radiation balance, biologic productivity and high-altitude ozone concentrations, as is evident from recent volcanic eruptions. SO(2) oxidation can occur via several different pathways that depend on its flux and the atmospheric conditions. An investigation into how SO(2) is oxidized to sulphate-the oxidation product preserved in the rock record-can therefore shed light on past volcanic eruptions and atmospheric conditions. Here we use sulphur and triple oxygen isotope measurements of atmospheric sulphate extracted from tuffaceous deposits to investigate the specific oxidation pathways from which the sulphate was formed. We find that seven eruption-related sulphate aerosol deposition events have occurred during the mid-Cenozoic era (34 to 7 million years ago) in the northern High Plains, North America. Two extensively sampled ash beds display a similar sulphate mixing pattern that has two distinct atmospheric secondary sulphates. A three-dimensional atmospheric sulphur chemistry and transport model study reveals that the observed, isotopically discrete sulphates in sediments can be produced only in initially alkaline cloudwater that favours an ozone-dominated SO(2) oxidation pathway in the troposphere. Our finding suggests that, in contrast to the weakly acidic conditions today, cloudwater in the northern High Plains may frequently have been alkaline during the mid-Cenozoic era. We propose that atmospheric secondary sulphate preserved in continental deposits represents an unexploited geological archive for atmospheric SO(2) oxidation chemistry linked to volcanism and atmospheric conditions in the past.

  12. 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.

  13. Effects of heating on composition, degree of darkness, and stacking nanostructure of soil humic acids.

    PubMed

    Katsumi, Naoya; Yonebayashi, Koyo; Okazaki, Masanori

    2016-01-15

    Wildfires and prescribed burning can affect both the quality and the quantity of organic matter in soils. In this study, we investigated qualitative and quantitative changes of soil humic substances in two different soils (an Entisol from a paddy field and an Inceptisol from a cedar forest) under several controlled heating conditions. Soil samples were heated in a muffle furnace at 200, 250, or 300 °C for 1, 3, 5, or 12h. The humic acid and fulvic acid contents of the soil samples prior to and after heating were determined. The degree of darkness, elemental composition, carbon and nitrogen stable isotope ratios, (13)C nuclear magnetic resonance spectra, and X-ray diffraction patterns of humic acids extracted from the soils before and after heating were measured. The proportion of humic acids in total carbon decreased with increasing heating time at high temperature (300 °C), but increased with increasing heating time at ≤ 250 °C. The degree of darkness of the humic acids increased with increasing heating time and temperature. During darkening, the H/C atomic ratios, the proportion of aromatic C, and the carbon and nitrogen stable isotope ratios increased, whereas the proportions of alkyl C and O-alkyl C decreased. X-ray diffraction analysis verified that a stacking nanostructure developed by heating. Changes in the chemical structure of the humic acids from the heated soils depended on the type of soil. The major structural components of the humic acids from the heated Entisol were aromatic C and carboxylic C, whereas aliphatic C, aromatic C, and carboxylic C structural components were found in the humic acids from the heated Inceptisol. These results suggest that the heat-induced changes in the chemical structure of the humic acids depended on the source plant. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. P Limitation and Microbial Biogeochemistry in Acidic Forest Soils of the Northeastern United States

    NASA Astrophysics Data System (ADS)

    Smemo, K. A.; Deforest, J. L.; Burke, D. J.; Elliot, H. L.; Kluber, L. A.; Carrino-Kyker, S. R.

    2010-12-01

    In forest ecosystems with acidic soils, such as many hardwood forests of the Northeastern United States, net primary productivity should be limited by phosphorus (P) because P is biologically less available at pH < 5 and nitrogen (N) has become more abundant in response to anthropogenic inputs. However, previous studies have failed to demonstrate widespread P limitation in temperate forests that have naturally acidic soil or are exposed to chronic acid deposition; such findings are contrary to biogeochemical expectations. We hypothesize that many eastern forests possess an underlying P limitation not realized at the ecosystem level. Instead, shifts in the composition, structure and function of soil microbial communities compensate by acquiring more P from organic sources and P limitation is therefore not manifested at the aboveground (plant) level. To test this hypothesis, we manipulated soil pH and P availability in 72 20 x 40 m mature hardwood forest plots across northeastern (glaciated) and southeastern (unglaciated) Ohio beginning in late summer 2009. Ten months after treatment initiation, soil pH has increased from 4.5 to 5.5 and soil P has increased from 3 to ~25 mg P/kg soil on glaciated soils and from 0.5 to ~5 mg P/kg soil on unglaciated soils. To quantify treatment responses, we measured the activity of soil extracellular enzymes associated with liberation of P, N, and C from organic matter, as well as pools of N and N cycling processes. We saw no significant effects of our treatments on pools of available ammonium or nitrate, nor did we see effects on net N mineralization and net nitrification rates. However, glaciated soils had significantly greater nitrate pools and higher N cycling rates than older unglaciated soils. Nitrogen and C cycling enzymes in treatment plots were not significantly different than control plots, but N-acetylglucosaminidase activity (N acquisition) was significantly greater in the unglaciated soils and β-glucosidase and

  15. Understanding the effect low molecular weight organic acids on the desorption and availability of soil phosphorus

    NASA Astrophysics Data System (ADS)

    Blackburn, Daniel; Zhang, Hao; Stutter, Marc; Giles, Courtney; George, Timothy; Shand, Charles; Lumsdon, David; Cooper, Pat; Wendler, Renate; Brown, Lawrie; Blackwell, Martin; Darch, Tegan; Wearing, Catherine; Haygarth, Philip

    2016-04-01

    The mobility and resupply of inorganic phosphorus (P) from the soil solid phase after equilibration with increasing doses of citric acid (CA) and oxalic acid (OA) were studied in 2 soils with contrasting P status. The combined methods of diffusive gradients in thin films (DGT), diffusive equilibration in thin films (DET) and the DGT-induced fluxes in sediments model (DIFS) were used as tools to evaluate the changes in solid-to-solution interchange kinetics. A significant effect of CA and OA in soil solution P was observed only for doses over 1 mMol kg-1. Curiously, low organic acid doses (0.5-1 mMol kg-1) were associated with a steep increase in microbial biomass P, which was not seen for doses over 2 mMol kg-1. The trivalent CA was able to promote a higher increase in soil solution P than the bivalent OA for both soils. Organic phosphorus was only significantly mobilized by organic acids in the low P soil, possibly because in the high P soil these P forms were less labile than inorganic P. Both CA and OA promoted a decrease in the adsorbed-to-solution distribution coefficient, desorption rate constants and an increase in the response time of solution P equilibration. The extent of this effect was shown to be both soil specific and organic acid specific. Since both organic acids negatively affected the kinetics of P interchange between the soil matrix and the soil solution, their net effect on P bioavailability is expected to be much lower than the observed increase in solution concentration.

  16. Microbial Mechanisms Underlying Acidity-induced Reduction in Soil Respiration Under Nitrogen Fertilization

    NASA Astrophysics Data System (ADS)

    Niu, S.; Li, Y.

    2016-12-01

    Terrestrial ecosystems are receiving increasing amounts of reactive nitrogen (N) due to anthropogenic activities, which largely changes soil respiration and its feedback to climate change. N enrichment can not only increase N availability but also induce soil acidification, both may affect soil microbial activity and root growth with a consequent impact on soil respiration. However, it remains unclear whether elevated N availability or soil acidity has greater impact on soil respiration (Rs). We conducted a manipulative experiment to simulate N enrichment (10 g m-2 yr-1 NH4NO3) and soil acidity (0.552 mol H+ m-2 yr-1 sulfuric acid) and studied their effects on Rs and its components in a temperate forest. Our results showed that soil pH was reduced by 0.2 under N addition or acid addition treatment. Acid addition significantly decreased autotrophic respiration (Ra) and heterotrophic respiration (Rh) by 21.5% and 22.7% in 2014, 34.8% and 21.9% in 2015, respectively, resulting in a reduction of Rs by 22.2% in 2014 and 26.1% in 2015. Nitrogen enrichment reduced Ra, Rh, Rs by 21.9%, 16.2%, 18.6% in 2014 and 22.1%, 5.9%, 11.7% in 2015, respectively. The reductions of Rs and its components were attributable to decrease of fine root biomass, microbial biomass, and cellulose degrading enzymes. N addition did not change microbial community but acid addition increased both fungal and arbuscular mycorrhiza fungi PLFAs, and N plus acid addition significantly enhanced fungal to bacterial ratio. All the hydrolase enzymes were reduced more by soil acidity (43-50%) than nitrogen addition (30-39%). Structural equation model showed that soil acidity played more important role than N availability in reducing soil respiration mainly by changing microbial extracellular enzymes. We therefore suggest that N deposition induced indirect effect of soil acidification on microbial properties is critical and should be taken into account to better understand and predict ecosystem C cycling in

  17. Mobilization of soil-borne arsenic by three common organic acids: Dosage and time effects.

    PubMed

    Onireti, Olaronke O; Lin, Chuxia

    2016-03-01

    A batch experiment was conducted to investigate the mobilization of soil-borne arsenic by three common low-molecular-weight organic acids with a focus on dosage and time effects. The results show that oxalic acid behaved differently from citric acid and malic acid in terms of mobilizing As that was bound to iron compounds. At an equivalent molar concentration, reactions between oxalic acid and soil-borne Fe were kinetically more favourable, as compared to those between either citric acid or malic acid and the soil-borne Fe. It was found that reductive dissolution of soil-borne Fe played a more important role in liberating As, as compared to non-reductive reactions. Prior to the 7th day of the experiment, As mobility increased with increasing dose of oxalic acid while there was no significant difference (P > 0.05) in mobilized As among the treatments with different doses of citric acid or malic acid. The dosage effect on soil-borne As mobilization in the citric acid and malic acid treatments became clear only after the 7th day of the experiment. Soluble Ca present in the soils could cause re-immobilization of As by competing with solution-borne Fe for available organic ligands to form practically insoluble organic compounds of calcium (i.e. calcium oxalate). This resulted in transformation of highly soluble organic complexes of iron (i.e. iron oxalate complexes) into slightly soluble organic compounds of iron (i.e. iron oxalate) or free ferric ion, which then reacted with the solution-borne arsenate ions to form practically insoluble iron arsenates in the latter part of the experiment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Influence of ingestion of aluminum, citric acid and soil on mineral metabolism of lactating beef cows.

    PubMed

    Allen, V G; Horn, F P; Fontenot, J P

    1986-05-01

    Lactating beef cows (16 Hereford and 34 Angus, 430 kg average body weight, aged 8 to 10 yr) were fed a basal diet containing 200 micrograms/g Al alone or supplemented with Al-citrate, citric acid, soil or soil plus citric acid for 56 d. Diets containing Al-citrate, soil and soil plus citric acid contained 1,730, 1,870 and 1,935 micrograms/g Al, dry-basis, respectively. Adding soil to the diet also increased Mg and Fe content of the diet. Aluminum values in ruminal contents of beef cows fed the basal alone or supplemented with citric acid, Al-citrate, soil or soil plus citric acid were 800, 990, 2,930, 3,410 and 2,910 micrograms/g, air-dry basis, respectively. Serum Mg and inorganic P declined (P less than .01) and urinary Ca concentration increased (P less than .01) for cows fed Al-citrate. By d 56, serum Mg was 1.5 and 2.2 mg/dl, and serum P was 3.8 and 6.8 mg/dl, for cows fed Al-citrate and basal diets, respectively. Calcium concentrations in urine were 281 and 11 micrograms/g for cows fed Al-citrate and basal diets, respectively. Citric acid, soil and soil plus citric acid had no detrimental effects on serum Mg and inorganic P, or urinary Ca concentration. By d 56, serum Ca was higher (P less than .06) in cows fed Al-citrate, compared with cows on the other four diets. Bone Ca, P, Zn and percent ash were not significantly affected by treatment but bone Mg tended to be slightly lower (P less than .07) for cows fed Al-citrate.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Soil acidity, temperature, and water relationships of four clovers in Sierra Nevada meadows

    Treesearch

    Raymond D. Ratliff; Ethelynda E. Harding

    1993-01-01

    Sites in meadows of the Sierra Nevada near Fresno, California, were studied to learn whether Bolander's (Trifolium holanderi Gray.), longstalked (T. longipes Nutt.), carpet (T. monanthum Gray.), and mountain (T. wormskioldii Lehm.) clovers occurred under the same soil acidity, temperature...

  20. 7 CFR 160.10 - Sulphate wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Sulphate wood turpentine. 160.10 Section 160.10... STANDARDS FOR NAVAL STORES General § 160.10 Sulphate wood turpentine. The designation “sulphate wood... in the sulphate process of cooking wood pulp, and commonly known as sulphate turpentine or...

  1. 7 CFR 160.10 - Sulphate wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Sulphate wood turpentine. 160.10 Section 160.10... STANDARDS FOR NAVAL STORES General § 160.10 Sulphate wood turpentine. The designation “sulphate wood... in the sulphate process of cooking wood pulp, and commonly known as sulphate turpentine or...

  2. 7 CFR 160.10 - Sulphate wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Sulphate wood turpentine. 160.10 Section 160.10... STANDARDS FOR NAVAL STORES General § 160.10 Sulphate wood turpentine. The designation “sulphate wood... in the sulphate process of cooking wood pulp, and commonly known as sulphate turpentine or...

  3. Chicken manure biochar as liming and nutrient source for acid Appalachian soil.

    PubMed

    Hass, Amir; Gonzalez, Javier M; Lima, Isabel M; Godwin, Harry W; Halvorson, Jonathan J; Boyer, Douglas G

    2012-01-01

    Acid weathered soils often require lime and fertilizer application to overcome nutrient deficiencies and metal toxicity to increase soil productivity. Slow-pyrolysis chicken manure biochars, produced at 350 and 700°C with and without subsequent steam activation, were evaluated in an incubation study as soil amendments for a representative acid and highly weathered soil from Appalachia. Biochars were mixed at 5, 10, 20, and 40 g kg into a Gilpin soil (fine-loamy, mixed, active, mesic Typic Hapludult) and incubated in a climate-controlled chamber for 8 wk, along with a nonamended control and soil amended with agronomic dolomitic lime (AgLime). At the end of the incubation, soil pH, nutrient availability (by Mehlich-3 and ammonium bicarbonate diethylene triamine pentaacetic acid [AB-DTPA] extractions), and soil leachate composition were evaluated. Biochar effect on soil pH was process- and rate-dependent. Biochar increased soil pH from 4.8 to 6.6 at the high application rate (40 g kg), but was less effective than AgLime. Biochar produced at 350°C without activation had the least effect on soil pH. Biochar increased soil Mehlich-3 extractable micro- and macronutrients. On the basis of unit element applied, increase in pyrolysis temperature and biochar activation decreased availability of K, P, and S compared to nonactivated biochar produced at 350°C. Activated biochars reduced AB-DTPA extractable Al and Cd more than AgLime. Biochar did not increase NO in leachate, but increased dissolved organic carbon, total N and P, PO, SO, and K at high application rate (40 g kg). Risks of elevated levels of dissolved P may limit chicken manure biochar application rate. Applied at low rates, these biochars provide added nutritional value with low adverse impact on leachate composition. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Bioavailability of heavy metals in strongly acidic soils treated with exceptional quality biosolids

    SciTech Connect

    Basta, N.T.; Sloan, J.J.

    1999-03-01

    New federal regulations may increase application of exceptional quality (EQ) biosolids to acidic soils, and information on the effect of this practice on bioavailability of heavy metal is limited. The objective of this study was to compare bioavailability of heavy metal in soil treated with nonalkaline or alkaline EQ biosolids with limestone-treated soils. Three acidic soils (pH 3.7--4.3) were treated with three amounts of lime-stabilized biosolids (LS), anaerobic-digested biosolids (AN), or agricultural limestone (L), and incubated at 25 C. Soil solution Cd, Zn, and other chemical constituents were measured at 1, 30, 90, and 180 d incubation. Soil solution Cd and Zn were AN > LS {ge} L, C. Soil solution Cd and Zn increased with AN applied but decreased wit h LS applied. The high application of LS had soil solution Zn dramatically decreased at soil pH > 5.5 and >5.1, respectively. Soil solution Cd and Zn increases were AN > LS with incubation time. Biosolids treatments increased heavy metal in Ca(NO{sub 3}){sub 2} and NaOAc fractions. Except for Cd, most metal from biosolids were in EDTA and HNO{sub 3} fractions. Heavy metal bioavailability, measured using lettuce (Latuca sativa L.), was AN > LS {ge} L, C. Although state regulations prohibiting application of nonalkaline EQ biosolids to acidic soil is a prudent practice, application of EQ alkaline biosolids that achieves soil pH > 5 minimizes risk from soil solution Cd and Zn and plant uptake of heavy metal.

  5. Emerging Technology Summary. ACID EXTRACTION TREATMENT SYSTEM FOR TREATMENT OF METAL CONTAMINATED SOILS

    EPA Science Inventory

    The Acid Extraction Treatment System (AETS) is intended to reduce the concentrations and/or teachability of heavy metals in contaminated soils so the soil can be returned to the site from which it originated. The objective of the project was to determine the effectiveness and com...

  6. Effect of tannic acid on the transcriptome of the soil bacterium Pseudomonas protegens Pf-5

    USDA-ARS?s Scientific Manuscript database

    Tannins are plant-produced organic compounds that are found in soils, are able to sequester iron, and have antimicrobial properties. We studied the effect of tannic acid on the molecular physiology of the soil-inhabiting biocontrol bacterium Pseudomonas protegens Pf-5 (formerly Pseudomonas fluoresce...

  7. Site-specific critical acid load estimates for forest soils in the Osborn Creek watershed, Michigan

    Treesearch

    Trevor Hobbs; Jason Lynch; Randy. Kolka

    2017-01-01

    Anthropogenic acid deposition has the potential to accelerate leaching of soil cations, and in turn, deplete nutrients essential to forest vegetation. The critical load concept, employing a simple mass balance (SMB) approach, is often used to model this process. In an evaluation under the U.S. Forest Service Watershed Condition Framework program, soils in all 6th level...

  8. Acid mist and soil Ca and Al alter the mineral nutrition and physiology of red spruce

    Treesearch

    P.G. Schaberg; D.H. DeHayes; G.J. Hawley; G.R. Strimbeck; J.R. Cumming; P.F. Murakami; C.H. Borer

    2000-01-01

    We examined the effects and potential interactions of acid mist and soil solution Ca and Al treatments on foliar cation concentrations, membrane-associated Ca (mCa), ion leaching, growth, carbon exchange, and cold tolerance of red spruce (Picea rubens Sarg.) saplings. Soil solution Ca additions increased foliar Ca and Zn concentrations, and increased...

  9. Emerging Technology Summary. ACID EXTRACTION TREATMENT SYSTEM FOR TREATMENT OF METAL CONTAMINATED SOILS

    EPA Science Inventory

    The Acid Extraction Treatment System (AETS) is intended to reduce the concentrations and/or teachability of heavy metals in contaminated soils so the soil can be returned to the site from which it originated. The objective of the project was to determine the effectiveness and com...

  10. FATTY ACID STABLE ISOTOPE INDICATORS OF MICROBIAL CARBON SOURCE IN TROPICAL SOILS

    EPA Science Inventory

    The soil microbial community plays an important role in tropical ecosystem functioning because of its importance in the soil organic matter (SOM) cycle. We have measured the stable carbon isotopic ratio (delta13C) of individual phospholipid fatty acids (PLFAs) in a variety of tr...

  11. USE OF FATTY ACID STABLE CARBON ISOTOPE RATIO TO INDICATE MICROBIAL CARBON SOURCE IN TROPICAL SOILS

    EPA Science Inventory


    We use measurements of the concentration and stable carbon isotope ratio of individual microbial phospholipid fatty acids (PLFAs) in soils as indicators of live microbial biomass levels, broad microbial community structure, and microbial carbon source. For studies of soil o...

  12. Regularities of extracting humic acids from soils using sodium pyrophosphate solutions

    NASA Astrophysics Data System (ADS)

    Bakina, L. G.; Drichko, V. F.; Orlova, N. E.

    2017-02-01

    Regularities of extracting humic acids from different soil types (soddy-podzolic soil, gray forest soil, and all chernozem subtypes) with sodium pyrophosphate solutions at different pH values (from 5 to 13) have been studied. It is found that, regardless of soil type, the process occurs in two stages through the dissociation of carboxylic groups and phenolic hydroxyls, each of which can be described by a logistic function. Parameters of the logistic equations approximating the extraction of humic acids from soils at different pH values are independent of the content and composition of humus in soils. Changes in the optical density of humic acids extracted from soils using sodium pyrophosphate solutions with different pH values are described in the first approximation by the Gaussian function. The optically densest humic acids are extracted using sodium pyrophosphate solutions at pH 10. Therefore, it is proposed to use an extract with pH 10 for the characterization of organic matter with the maximum possible degree of humification in the given soil.

  13. Forms and Lability of Phosphorus in Humic Acid Fractions of Hord Silt Loam Soil

    USDA-ARS?s Scientific Manuscript database

    Phosphorus (P) has long been known to be present in soil humic fractions, but little is known about specific P forms in humic fractions, or their lability. We extracted the mobile humic acid (MHA) and recalcitrant calcium humate (CaHA) fractions from a Nebraska Hord silt loam soil under continuous c...

  14. USE OF FATTY ACID STABLE CARBON ISOTOPE RATIO TO INDICATE MICROBIAL CARBON SOURCE IN TROPICAL SOILS

    EPA Science Inventory


    We use measurements of the concentration and stable carbon isotope ratio of individual microbial phospholipid fatty acids (PLFAs) in soils as indicators of live microbial biomass levels, broad microbial community structure, and microbial carbon source. For studies of soil o...

  15. Ameliorating soil acidity of tropical Oxisols by liming for sustainable crop production

    USDA-ARS?s Scientific Manuscript database

    The greatest potential for expanding the world’s agricultural frontier lies in the savanna regions of the tropics, which are dominated by Oxisols. Soil acidity and low native fertility, however, are major constraints for crop production on tropical Oxisols. Soil acidification is an ongoing natural p...

  16. FATTY ACID STABLE ISOTOPE INDICATORS OF MICROBIAL CARBON SOURCE IN TROPICAL SOILS

    EPA Science Inventory

    The soil microbial community plays an important role in tropical ecosystem functioning because of its importance in the soil organic matter (SOM) cycle. We have measured the stable carbon isotopic ratio (delta13C) of individual phospholipid fatty acids (PLFAs) in a variety of tr...

  17. Effects of nitrogen fertilization on the acidity and salinity of greenhouse soils.

    PubMed

    Han, Jiangpei; Shi, Jiachun; Zeng, Lingzao; Xu, Jianming; Wu, Laosheng

    2015-02-01

    A greenhouse pot experiment was conducted to study the effects of conventional nitrogen fertilization on soil acidity and salinity. Three N rates (urea; N0, 0 kg N ha(-1); N1, 600 kg N ha(-1); and N2, 1,200 kg N ha(-1)) were applied in five soils with different greenhouse cultivation years to evaluate soil acidification and salinization rate induced by nitrogen fertilizer in lettuce production. Both soil acidity and salinity increased significantly as N input increased after one season, with pH decrease ranging from 0.45 to 1.06 units and electrolytic conductivity increase from 0.24 to 0.68 mS cm(-1). An estimated 0.92 mol H(+) was produced for 1 mol (NO2 (-) + NO3 (-))-N accumulation in soil. The proton loading from nitrification was 14.3-27.3 and 12.1-58.2 kmol H(+) ha(-1) in the center of Shandong Province under N1 and N2 rate, respectively. However, the proton loading from the uptake of excess bases by lettuces was only 0.3-4.5 % of that from nitrification. Moreover, the release of protons induced the direct release of base cations and accelerated soil salinization. The increase of soil acidity and salinity was attributed to the nitrification of excess N fertilizer. Compared to the proton loading by lettuce, nitrification contributed more to soil acidification in greenhouse soils.

  18. Effects of Fe oxide on N transformations in subtropical acid soils

    PubMed Central

    Jiang, Xianjun; Xin, Xiaoping; Li, Shiwei; Zhou, Junchao; Zhu, Tongbin; Müller, Christopher; Cai, Zucong; Wright, Alan L.

    2015-01-01

    Subtropical ecosystems are often characterized by high N cycling rates, but net nitrification rates are often low in subtropical acid soils. NO3−-N immobilization into organic N may be a contributing factor to understand the observed low net nitrification rates in these acid soils. The effects of Fe oxide and organic matter on soil N transformations were evaluated using a 15N tracing study. Soil net nitrification was low for highly acidic yellow soil (Ferralsols), but gross ammonia oxidation was 7 times higher than net nitrification. In weakly acidic purple soil (Cambisols), net nitrification was 8 times higher than in Ferralsols. The addition of 5% Fe oxide to Cambisols, reduced the net nitrification rate to a negative rate, while NO3−-N immobilization rate increased 8 fold. NO3−-N immobilization was also observed in Ferralsols which contained high Fe oxides levels. A possible mechanism for these reactions could be stimulation of NO3−-N immobilization by Fe oxide which promoted the abiotic formation of nitrogenous polymers, suggesting that the absence of net nitrification in some highly acid soils may be due to high rates of NO3−-N immobilization caused by high Fe oxide content rather than a low pH. PMID:25722059

  19. Adsorption and mobility of Cr(III)-organic acid complexes in soils.

    PubMed

    Cao, Xinhua; Guo, Jing; Mao, Jingdong; Lan, Yeqing

    2011-09-15

    The soluble Cr(III) is likely to be complexed with organic ligands in ligand-rich soil. Cr(VI) chemical reduction by organic acids and bioreduction by microorganisms can produce soluble Cr(III)-organic acids complexes. Thus, it is of great significance to investigate the absorption and mobility of Cr(III)-organic acid complexes in soils. In this study, Cr(III)-EDTA and Cr(III)-cit were prepared and purified, and then were examined for adsorption and mobility. The results demonstrated that Cr(III) was strongly bound to soil, while Cr(III)-organic acid complexes had no or slight interaction with soils since Cr(III)-EDTA and Cr(III)-cit complexes mainly existed as the forms of [Cr(III)-EDTA](-) and [Cr(III)-cit], respectively, under the tested conditions with initial pH 4.0-9.0. The adsorption of Cr(III) increased but that of Cr(III)-organic acid complexes decreased with the content of soil organic matter. Compared with Cr(III)-EDTA, the mobility of Cr(III)-cit in soil columns was reduced, due to the specific adsorption between soils and Cr(III)-cit which contained one free hydroxyl group. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Detrimental effects of boric-acid-treated soil against foraging subterranean termites (Isoptera: Rhinotermitidae)

    Treesearch

    Bradford M. Kard

    2001-01-01

    111 laboratory bioassays, boric acid (BA) mixed with soil caused significant subterranean termite mortality. In clloice tests, eastern subterranean and Formosan subterranean tennites were exposed to boric acid mixed with soil at concentrations of 0.05, 0.25, 0.50, 1.00, 2.00, and 4.00 percent Al (wt:wt). Termites could choose to remain in their main nests wit13 non-...

  1. Contributions of acid deposition and natural processes to cation leaching from forest soils: a review

    SciTech Connect

    Johnson, D.W.; Van Miegroet, H.; Cole, D.W.; Richter, D.D.

    1983-01-01

    Methods of quantifying the roles of atmospheric acid inputs and internal acid generation by carbonic, organic, and nitric acids are illustrated by reviewing data sets from several intensively studied sites in North America. Some of the sites (tropical, Costa Rica (La Selva); temperate deciduous, Tennessee (Walker Branch); and temperate coniferous, Washington (Thompson)) received acid precipitation whereas others (northern, southeast Alaska (Petersburg); and subalpine, Washington Cascades (Findley Lake)) did not. Natural leaching by carbonic acid dominated soil leaching in the tropical and temperate coniferous sites, nitric acid (caused by nitrification) dominated leaching in an N-fixing temperate deciduous site (red alder in Washington), and organic acids dominated surface soil leaching in the subalpine site and contributed to leaching of surface soils in several other sites. Only at the temperate deciduous sites in eastern Tennessee did atmospheric acid input play a major role in soil leaching. In no case, however, are the annual net losses of cations regarded as alarming as compared to soil exchangeable cation capital.

  2. Composition of exchangeable bases and acidity in soils of the Crimean Mountains

    NASA Astrophysics Data System (ADS)

    Kostenko, I. V.

    2015-08-01

    Acid forest and mountainous meadow soils of the Crimean Mountains were studied. The amount of hydrogen and aluminum ions extracted from these soils depended on the pH of extracting agents. The maximum values of the soil acidity were obtained upon the extraction with a strongly alkaline solution of sodium acetate in 0.05 N NaOH. The application of this extractant made it possible to determine the total exchange acidity, the total amount of extractable aluminum, and the total cation exchange capacity of the soils after the extraction of all the acidic components from them. The values of these characteristics were significantly higher than the values of the potential acidity and cation exchange capacity obtained by the routine analytical methods. Hydrogen predominated among the acidic components of the exchange acidity in the humus horizons, whereas aluminum predominated among them in the underlying mineral horizons. Hydrothermic conditions and the character of vegetation and parent materials were the major factors affecting the relationships between bases and acidic components in the soil adsorption complex.

  3. Effects of discharging acid-mine drainage into evaporation ponds lined with clay on chemical quality of the surrounding soil and water

    NASA Astrophysics Data System (ADS)

    Mapanda, F.; Nyamadzawo, G.; Nyamangara, J.; Wuta, M.

    Compacted clay layers are commonly used as liners to limit acid-mine drainage (AMD) percolation into the surrounding environment from containment areas or ponds. In the long term, this practical and sometimes economical means of AMD disposal has often presented other considerable environmental challenges. The chemical quality of soil, river water and groundwater surrounding evaporation ponds lined with clay was determined at Iron-Duke Mine in Glendale, Zimbabwe. At this mine over 150 m 3/d of wastewater containing AMD were discharged daily for over a decade. The soils located downslope in relation to the ponds and closer to the ponds were acidified (pH 2.8-4.4) and enriched with salts. The level of contamination was highest within 15 m from the ponds and at 2-6 m depths from the surface. The variability in soil pH and electrical conductivity with position, distance from the ponds and depth from surface was attributed to the vertical and lateral flow of contaminated groundwater containing leachates from the ponds. The groundwater and river water surrounding the ponds were contaminated with arsenic (As), iron (Fe), nickel (Ni), sulphate, salts and acidity, and the level of contamination increased with proximity to the ponds. Potential public health hazards from consumption of the groundwater and river water were high. It was concluded that discharging of AMD into the ponds has not been an environmentally effective means of AMD containment and disposal. There was need for better AMD disposal means, particularly those that would improve the containment of AMD to reduce its seepage.

  4. Dolomite application to acidic soils: a promising option for mitigating N2O emissions.

    PubMed

    Shaaban, Muhammad; Peng, Qi-An; Hu, Ronggui; Wu, Yupeng; Lin, Shan; Zhao, Jinsong

    2015-12-01

    Soil acidification is one of the main problems to crop productivity as well as a potent source of atmospheric nitrous oxide (N2O). Liming practice is usually performed for the amelioration of acidic soils, but the effects of dolomite application on N2O emissions from acidic soils are still not well understood. Therefore, a laboratory study was conducted to examine N2O emissions from an acidic soil following application of dolomite. Dolomite was applied to acidic soil in a factorial design under different levels of moisture and nitrogen (N) fertilizer. Treatments were as follows: dolomite was applied as 0, 1, and 2 g kg(-1) soil (named as CK, L, and H, respectively) under two levels of moisture [i.e., 55 and 90 % water-filled pore space (WFPS)]. All treatments of dolomite and moisture were further amended with 0 and 200 mg N kg(-1) soil as (NH4)2SO4. Soil properties such as soil pH, mineral N (NH4 (+)-N and NO3 (-)-N), microbial biomass carbon (MBC), dissolved organic carbon (DOC), and soil N2O emissions were analyzed throughout the study period. Application of N fertilizer rapidly increased soil N2O emissions and peaked at 0.59 μg N2O-N kg(-1) h(-1) under 90 % WFPS without dolomite application. The highest cumulative N2O flux was 246.32 μg N2O-N kg(-1) under 90 % WFPS without dolomite addition in fertilized soil. Addition of dolomite significantly (p ≤ 0.01) mitigated N2O emissions as soil pH increased, and H treatment was more effective for mitigating N2O emissions as compared to L treatment. The H treatment decreased the cumulative N2O emissions by up to 73 and 67 % under 55 and 90 % WFPS, respectively, in fertilized soil, and 60 and 68 % under 55 and 90 % WFPS, respectively, in unfertilized soil when compared to those without dolomite addition. Results demonstrated that application of dolomite to acidic soils is a promising option for mitigating N2O emissions.

  5. Temperature effects on protein depolymerization and amino acid immobilization rates in soils.

    NASA Astrophysics Data System (ADS)

    Noll, Lisa; Hu, Yuntao; Zhang, Shasha; Zheng, Qing; Wanek, Wolfgang

    2017-04-01

    Increasing N deposition, land use change, elevated atmospheric CO2 concentrations and global warming have altered soil nitrogen (N) cycling during the last decades. Those changes affected ecosystem services, such as C and N sequestration in soils, which calls for a better understanding of soil N transformation processes. The cleavage of macromolecular organic N by extracellular enzymes maintains an ongoing flow of new bioavailable organic N into biotic systems and is considered to be the bottle neck of terrestrial N cycling in litter and soils. Recent studies showed that protein depolymerization is susceptible to changes in C and N availabilities. Based on general biological observations the temperature sensitivity of soil organic N processes is expected to depend on whether they are rather enzyme limited (i.e. Q10=2) or diffusion limited (i.e. Q10= 1.0 - 1.3). However, temperature sensitivities of protein depolymerization and amino acid immobilization are still unknown. We therefore here report short-term temperature effects on organic N transformation rates in soils differing in physicochemical parameters but not in climate. Soil samples were collected from two geologically distinct sites close to the LFZ Raumberg-Gumpenstein, Styria, Austria, each from three different management types (arable land, grassland, forest). Four replicates of mineral soil were taken from every site and management type. The area provides a unique opportunity to study geological and management controls in soils without confounding effects of climate and elevation. The soils differ in several soil chemical parameters, such as soil pH, base saturation, soil C: N ratio and SOM content as well as in soil physical parameters, such as soil texture, bulk density and water holding capacity. Soils were pre-incubated at 5, 15 and 25˚ C for one day. Protein depolymerization rates and amino acid immobilization rates were assessed by an isotope pool dilution assay with 15N labeled amino acids at

  6. Mechanisms of soil humic acid adsorption onto montmorillonite and kaolinite.

    PubMed

    Chen, Hongfeng; Koopal, Luuk K; Xiong, Juan; Avena, Marcelo; Tan, Wenfeng

    2017-10-15

    To explore the adsorption mechanisms of a soil humic acid (HA) on purified kaolinite and montmorillonite, a combination of adsorption measurements, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and isothermal titration calorimetry (ITC) was employed at pH 4.0, 6.0 and 8.0. The adsorption affinities and plateaus of HA on the two clays increased with decreasing pH, indicating the importance of electrostatic interaction. The effects were more significant for kaolinite than for montmorillonite. The substantial adsorption at pH 8.0 indicated hydrophobic interaction and/or H-bonding also played a role. The ATR-FTIR results at pH 8.0 showed that the Si-O groups located at basal faces of the two clays were involved in the adsorption process. For kaolinite, at pH 4.0 and 6.0, HA adsorption occurred via OH groups on the edge faces and basal octahedral faces (both positively charged), plus some adsorption at Si-O group. The exothermic molar adsorption enthalpy decreased relatively dramatically with adsorption up to adsorption values of 0.7μmol/g on montmorillonite and 1.0μmol/g on kaolinite, but the decrease was attenuated at higher adsorption. The high exothermic molar enthalpy of HA binding to the clays was ascribed to ligand exchange and electrostatic binding, which are enthalpy-driven. At high adsorption values, JGHA adsorption by hydrophobic attraction and H-bonding also occurs. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Murine T lymphocytes and T-lymphoma cells produce chondroitin sulphate and heparan sulphate proteoglycans and free heparan sulphate glycosaminoglycan.

    PubMed Central

    Wilson, A P; Rider, C C

    1991-01-01

    Normal murine splenic T lymphocytes and T-lymphoma cells were incubated with [35S]sulphate in low-sulphate medium for 4 hr. Gel filtration and SDS-PAGE revealed that the radiolabelled macromolecules secreted by these cells were almost exclusively chondroitin sulphate and heparan sulphate proteoglycans of relatively low molecular weight (MW), 100,000-200,000. Triton X-100 extracts of the cells contained similar proteoglycans. Under the conditions employed the incorporation of radiolabel by cells grown in vivo was equally distributed between cell-retained and secreted fractions, whereas cells grown in vitro retained some 75% of incorporated label. In general heparan sulphate predominated over chondroitin sulphate in both secreted and cell-retained fractions. Cell extracts also contained a minor proportion of free glycosaminoglycan, which is almost exclusively heparan sulphate. These chains, like those incorporated into the proteoglycan, were around 12,000 MW. The T-lymphoma cells RDM-4, whether grown in vitro or in vivo, also incorporated a substantial proportion of [35S]sulphate into a single, cell-retained protein, 100,000 MW. No such radiolabelled protein was detectable in T cells. Images Figure 3 Figure 4 Figure 5 PMID:1900056

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

    PubMed

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

    2016-11-09

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

  9. How do crop plants tolerate acid soils? Mechanisms of aluminum tolerance and phosphorous efficiency.

    PubMed

    Kochian, Leon V; Hoekenga, Owen A; Pineros, Miguel A

    2004-01-01

    Acid soils significantly limit crop production worldwide because approximately 50% of the world's potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring tolerance to acid soil stress has been a focus of intense research interest over the past decade. The primary limitations on acid soils are toxic levels of aluminum (Al) and manganese (Mn), as well as suboptimal levels of phosphorous (P). This review examines our current understanding of the physiological, genetic, and molecular basis for crop Al tolerance, as well as reviews the emerging area of P efficiency, which involves the genetically based ability of some crop genotypes to tolerate P deficiency stress on acid soils. These are interesting times for this field because researchers are on the verge of identifying some of the genes that confer Al tolerance in crop plants; these discoveries will open up new avenues of molecular/physiological inquiry that should greatly advance our understanding of these tolerance mechanisms. Additionally, these breakthroughs will provide new molecular resources for improving crop Al tolerance via both molecular-assisted breeding and biotechnology.

  10. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    NASA Astrophysics Data System (ADS)

    Karicheva, E.; Guseva, N.; Kambalina, M.

    2016-03-01

    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  11. Soil calcium status and the response of stream chemistry to changing acidic deposition rates

    USGS Publications Warehouse

    Lawrence, G.B.; David, M.B.; Lovett, Gary M.; Murdoch, Peter S.; Burns, Douglas A.; Stoddard, J.L.; Baldigo, Barry P.; Porter, J.H.; Thompson, A.W.

    1999-01-01

    Despite a decreasing trend in acidic deposition rates over the past two to three decades, acidified surface waters in the northeastern United States have shown minimal changes. Depletion of soil Ca pools has been suggested as a cause, although changes in soil Ca pools have not been directly related to long-term records of stream chemistry. To investigate this problem, a comprehensive watershed study was conducted in the Neversink River Basin, in the Catskill Mountains of New York, during 1991-1996. Spatial variations of atmospheric deposition, soil chemistry, and stream chemistry were evaluated over an elevation range of 817-1234 m to determine whether these factors exhibited elevational patterns. An increase in atmospheric deposition of SO4 with increasing elevation corresponded with upslope decreases of exchangeable soil base concentrations and acid-neutralizing capacity of stream water. Exchangeable base concentrations in homogeneous soil incubated within the soil profile for one year also decreased with increasing elevation. An elevational gradient in precipitation was not observed, and effects of a temperature gradient on soil properties were not detected. Laboratory leaching experiments with soils from this watershed showed that (1) concentrations of Ca in leachate increased as the concentrations of acid anions in added solution increased, and (2) the slope of this relationship was positively correlated with base saturation. Field and laboratory soil analyses are consistent with the interpretation that decreasing trends in acid-neutralizing capacity in stream water in the Neversink Basin, dating back to 1984, are the result of decreases in soil base saturation caused by acidic deposition.

  12. Selenium speciation in acidic environmental samples: application to acid rain-soil interaction at Mount Etna volcano.

    PubMed

    Floor, Geerke H; Iglesías, Mònica; Román-Ross, Gabriela; Corvini, Philippe F X; Lenz, Markus

    2011-09-01

    Speciation plays a crucial role in elemental mobility. However, trace level selenium (Se) speciation analyses in aqueous samples from acidic environments are hampered due to adsorption of the analytes (i.e. selenate, selenite) on precipitates. Such solid phases can form during pH adaptation up till now necessary for chromatographic separation. Thermodynamic calculations in this study predicted that a pH<4 is needed to prevent precipitation of Al and Fe phases. Therefore, a speciation method with a low pH eluent that matches the natural sample pH of acid rain-soil interaction samples from Etna volcano was developed. With a mobile phase containing 20mM ammonium citrate at pH 3, selenate and selenite could be separated in different acidic media (spiked water, rain, soil leachates) in <10 min with a LOQ of 0.2 μg L(-1) using (78)Se for detection. Applying this speciation analysis to study acid rain-soil interaction using synthetic rain based on H(2)SO(4) and soil samples collected at the flanks of Etna volcano demonstrated the dominance of selenate over selenite in leachates from samples collected close to the volcanic craters. This suggests that competitive behavior with sulfate present in acid rain might be a key factor in Se mobilization. The developed speciation method can significantly contribute to understand Se cycling in acidic, Al/Fe rich environments. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Sorption of vapors of some organic liquids on soil humic acid and its relation to partitioning of organic compounds in soil organic matter

    USGS Publications Warehouse

    Chlou, G.T.; Kile, D.E.; Malcolm, R.L.

    1988-01-01

    Vapor sorption of water, ethanol, benzene, hexane, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,2-dibromoethane on (Sanhedron) soil humic acid has been determined at room temperature. Isotherms for all organic liquids are highly linear over a wide range of relative pressure (P/P??), characteristic of the partitioning (dissolution) of the organic compounds in soil humic acid. Polar liquids exhibit markedly greater sorption capacities on soil humic acid than relatively nonpolar liquids, in keeping with the polar nature of the soil humic acid as a partition medium. The limiting sorption (partition) capacities of relatively non-polar liquids are remarkably similar when expressed in terms of volumes per unit weight of soil humic acid. The soil humic acid is found to be about half as effective as soil organic matter in sorption of relatively nonpolar organic compounds. The nearly constant limiting sorption capacity for nonpolar organic liquids with soil humic acid on a volume-to-weight basis and its efficiency in sorption relative to soil organic matter provide a basis for predicting the approximate sorption (partition) coefficients of similar compounds in uptake by soil in aqueous systems.

  14. Using poly-glutamic acid as soil-washing agent to remediate heavy metal-contaminated soils.

    PubMed

    Yang, Zong-Han; Dong, Cheng-Di; Chen, Chiu-Wen; Sheu, Yih-Terng; Kao, Chih-Ming

    2017-05-20

    The extraction efficiency of heavy metals from soils using three forms of gamma poly-glutamic acid (γ-PGA) as the washing agents was investigated. Controlling factors including agent concentrations, extraction time, pH, and liquid to soil ratio were evaluated to determine the optimum operational conditions. The distribution of heavy metal species in soils before and after extraction processes was analyzed. Up to 46 and 74% of heavy metal removal efficiencies were achieved with one round and a sequential extraction process using H-bonding form of γ-PGA (200 mM) with washing time of 40 min, liquid to solid ratio of 10 to 1, and pH of 6. Major heavy metal removal mechanisms were (1) γ-PGA-promoted dissolution and (2) complexation of heavy metal with free carboxyl groups in γ-PGA, which resulted in heavy metal desorption from soils. Metal species on soils were redistributed after washing, and soils were remediated without destruction of soil structures and productivity.

  15. Thermal properties of lithium sulphate

    NASA Astrophysics Data System (ADS)

    Suleiman, B. M.; Gustavsson, M.; Karawacki, E.; Lundén, A.

    1997-09-01

    The thermal conductivity and diffusivity of lithium sulphate have been measured simultaneously, using the transient plane source technique over the temperature range 300 - 900 K. The thermal conductivity decreases slowly up to about 640 K, whereupon a distinct rise occurs, indicating the onset of a pre-transitional behaviour, which causes a continuous growth of the conductivity up to the structural phase transition at 851 K, whereupon a very sharp increase occurs. A similar behaviour has been observed for the thermal diffusivity, for which a very sharp dip occurs at the transition point due to the exceptionally large transition enthalpy. The pre-transitional behaviour of heat transport is associated with the librational disorder of the sulphate anions known from Raman scattering studies of both phases (and neutron scattering from the cubic phase), whereas the translational disorder of lithium cations is of hardly any importance. It is thus possible to link the `paddle-wheel' concept of ion migration in the cubic phase to the enhancement of heat transport observed in the `pre-transition' region, as well as to the large difference in heat-transport rates between the monoclinic and cubic phases.

  16. Nitrogen saturation, soil acidification, and ecological effects in a subtropical pine forest on acid soil in southwest China

    NASA Astrophysics Data System (ADS)

    Huang, Yongmei; Kang, Ronghua; Mulder, Jan; Zhang, Ting; Duan, Lei

    2015-11-01

    Elevated anthropogenic nitrogen (N) deposition has caused nitrate (NO3-) leaching, an indication of N saturation, in several temperate and boreal forests across the Northern Hemisphere. So far, the occurrence of N saturation in subtropical forests and its effects on the chemistry of the typically highly weathered soils, forest growth, and biodiversity have received little attention. Here we investigated N saturation and the effects of chronically high N inputs on soil and vegetation in a typical, subtropical Masson pine (Pinus massoniana) forest at Tieshanping, southwest China. Seven years of N flux data obtained in ambient conditions and in response to field manipulation, including a doubling of N input either as ammonium nitrate (NH4NO3) or as sodium nitrate (NaNO3) solution, resulted in a unique set of N balance data. Our data showed extreme N saturation with near-quantitative leaching of NO3-, by far the dominant form of dissolved inorganic N in soil water. Even after 7 years, NH4+, added as NH4NO3, was nearly fully converted to NO3-, thus giving rise to a major acid input into the soil. Despite the large acid input, the decrease in soil pH was insignificant, due to pH buffering caused by Al3+ mobilization and enhanced SO42- adsorption. In response to the NH4NO3-induced increase in soil acidification and N availability, ground vegetation showed significant reduction of abundance and diversity, while Masson pine growth further declined. By contrast, addition of NaNO3 did not cause soil acidification. The comparison of NH4NO3 treatment and NaNO3 treatment indicated that pine growth decline was mainly attributed to acidification-induced nutrient imbalance, while the loss in abundance of major ground species was the combining effect of N saturation and acidification. Therefore, N emission control is of primary importance to curb further acidification and eutrophication of forest soils in much of subtropical south China.

  17. Stromal accumulation of chondroitin sulphate in mammary tumours of dogs

    PubMed Central

    Hinrichs, U; Rutteman, G R; Nederbragt, H

    1999-01-01

    To contribute to the investigation of the composition of the extracellular matrix in epithelial tumours, mammary gland tissues of dogs (including tumours, hyperplasias and normal tissue as well as metastatic lesions in lymph nodes and lung) were studied histochemically and immunohistochemically for distribution of sulphated glycosaminoglycans (s-GAGs). The formaline-fixed tissue was stained by alcian blue at pH 5.8, using the ‘critical electrolyte concentration’ to study the degree of sulphation of s-GAGs. s-GAGs were characterized by degradation with enzymes and nitrous acid and by immunohistochemistry with two anti-chondroitin sulphate monoclonal antibodies. The light microscopic investigation of s-GAG deposits revealed a limited number of patterns of their distribution. The main s-GAGs found in the mammary gland tumours of dogs and in metastatic lesions were chondroitin sulphate (CS) and heparin/heparan sulphate (HEP/HS). CS accumulated in diffuse structures between epithelial cells as well as around clusters of tumour cells. The latter pattern, possibly representing a mesenchymal reaction to the tumour, was present in 74% of the tumours, and in 67% of these, highly sulphated CS was present. A diffuse accumulation of CS was present almost exclusively in complex and mixed tumours; because of the expression of the 3B3 epitope for CS in immature cartilage the spindle cells of complex tumours are argued to be the precursors of the cartilage in mixed tumours. HEP/HS was stored mainly in mast cells that were found in increased numbers in hyperplasias and tumours. By pretreatment of microscopic slides with chondroitinase AC or ABC immunostaining of fibronectin could be made possible in areas in which CS was abundantly present, suggesting that CS may mask fibronectin epitopes. It is concluded that CS with different degrees of sulphation is the most important s-GAG in the extracellular matrix of mammary tumours of dogs. CS and other s-GAGs accumulate at different

  18. Ameliorating soil acidity and physical properties of two contrasting texture Ultisols with wastewater sludge biochar.

    PubMed

    Zong, Yutong; Wang, Yefeng; Sheng, Ye; Wu, Chengfeng; Lu, Shenggao

    2017-06-21

    The production of biochar is a safe and beneficial disposal way for wastewater sludge. The biochar produced from wastewater sludge can be used as soil amendments for improving soil properties and for increasing crop yield. This work investigated the influences of wastewater sludge biochar (WSB) on the pH, exchangeable acidity, and physical properties of strongly acidic Ultisols with contrasting texture (clayey soil and sandy loam). Two soils were mixed with WSB at the rate of 0, 10, 20, and 40 g biochar kg(-1) soil and incubated for 240 days at 75% field water capacity. Incubation experimental results indicated that WSB significantly increased soil pH and exchangeable Ca(2+) and Mg(2+) contents, and decreased soil exchangeable H(+) and Al(3+), compared with the control. The application of WSB enhanced the formation of 5-2-mm macroaggregate, and decreased the content of <0.25-mm microaggregate. WSB application significantly increased aggregate stability of soils, determined by mean weight diameter (MWD) of aggregate. WSB increased the field water capacity and available water content (AWC) of sandy loam while WSB was not found to increase significantly water-holding capacity and AWC of clayey soil. WSB significantly reduced plastic index and tensile strength (TS) of clayey soil and did not alter the TS of sandy loam. Overall results suggest that WSB is a suitable amendment for strongly acidic Ultisols with poor physical properties. However, the soil texture affected greatly the improvement effect of WSB on poor physical properties in soils.

  19. Links between Ammonia Oxidizer Community Structure, Abundance, and Nitrification Potential in Acidic Soils ▿ †

    PubMed Central

    Yao, Huaiying; Gao, Yangmei; Nicol, Graeme W.; Campbell, Colin D.; Prosser, James I.; Zhang, Limei; Han, Wenyan; Singh, Brajesh K.

    2011-01-01

    Ammonia oxidation is the first and rate-limiting step of nitrification and is performed by both ammonia-oxidizing archaea (AOA) and bacteria (AOB). However, the environmental drivers controlling the abundance, composition, and activity of AOA and AOB communities are not well characterized, and the relative importance of these two groups in soil nitrification is still debated. Chinese tea orchard soils provide an excellent system for investigating the long-term effects of low pH and nitrogen fertilization strategies. AOA and AOB abundance and community composition were therefore investigated in tea soils and adjacent pine forest soils, using quantitative PCR (qPCR), terminal restriction fragment length polymorphism (T-RFLP) and sequence analysis of respective ammonia monooxygenase (amoA) genes. There was strong evidence that soil pH was an important factor controlling AOB but not AOA abundance, and the ratio of AOA to AOB amoA gene abundance increased with decreasing soil pH in the tea orchard soils. In contrast, T-RFLP analysis suggested that soil pH was a key explanatory variable for both AOA and AOB community structure, but a significant relationship between community abundance and nitrification potential was observed only for AOA. High potential nitrification rates indicated that nitrification was mainly driven by AOA in these acidic soils. Dominant AOA amoA sequences in the highly acidic tea soils were all placed within a specific clade, and one AOA genotype appears to be well adapted to growth in highly acidic soils. Specific AOA and AOB populations dominated in soils at particular pH values and N content, suggesting adaptation to specific niches. PMID:21571885

  20. Extractive and oxidative removal of copper bound to humic acid in soil.

    PubMed

    Hwang, Bo-Ram; Kim, Eun-Jung; Yang, Jung-Seok; Baek, Kitae

    2015-04-01

    Copper (Cu) is often found strongly bound to natural organic matter (NOM) in soil through the formation of strong Cu-NOM complexes. Therefore, in order to successfully remediate Cu-contaminated soils, effective removal of Cu bound to soil organic matter should be considered. In this study, we investigated soil washing methods for Cu removal from a synthetic Cu-contaminated model silica soil coated with humic acid (HA) and from field contaminated soil. Various reagents were studied to extract Cu bound to NOM, which included oxidant (H2O2), base (NaOH), and chelating agents (citric acid and ethylenediaminetetraacetic acid (EDTA)). Among the wash reagents, EDTA extracted Cu most effectively since EDTA formed very strong complexes with Cu, and Cu-HA complexes were transformed into Cu-EDTA complexes. NaOH extracted slightly less Cu compared to EDTA. HA was effectively extracted from the model soil under strongly alkaline conditions with NaOH, which seemed to concurrently release Cu bound to HA. However, chemical oxidation with H2O2 was not effective at destroying Cu-HA complexes. Fourier transform infrared spectroscopy and elemental analysis revealed that chelating agents such as citrate and EDTA were adsorbed onto the model soil via possible complexation between HA and extraction agents. The extraction of Cu from a field contaminated soil sample was effective with chelating agents, while oxidative removal with H2O2 and extractive removal with NaOH separated negligible amounts of Cu from the soil. Based on these results, Cu bound to organic matter in soil could be effectively removed by chelating agents, although remnant agents may remain in the soil.

  1. Daily and seasonal changes in soil amino acid composition in a semiarid grassland exposed to elevated CO2 and warming

    USDA-ARS?s Scientific Manuscript database

    Soil amino acids are often an important source of nitrogen (N) for plants, and anticipated global changes, including climate warming and rising atmospheric CO2 levels, have the potential to alter plant and microbial production and consumption of this N source in soils. We determined soil amino acid ...

  2. Development of an Inhaled Sustained Release Dry Powder Formulation of Salbutamol Sulphate, an Antiasthmatic Drug

    PubMed Central

    Kumaresan, C.; Sathishkumar, K.

    2016-01-01

    The present research was aimed to develop and characterize a sustained release dry powder inhalable formulation of salbutamol sulphate. The salbutamol sulphate microparticles were prepared by solvent evaporation method using biodegradable polymer poly (D,L-lactic-co-glycolic acid) to produce salbutamol sulphate microparticle mixed with carrier respirable grade lactose for oral inhalation of dry powder. The drug content were estimated to produce 1 mg sustained release salbutamol sulphate per dose. Total four formulations K1, K2, K3 and K4 were prepared with 1:1, 1:2, 1:3, 1:4 ratio of salbutamol sulphate:poly (D,L-lactic-co-glycolic acid). The developed formulations were studied for physicochemical properties, in vitro drug relase and Anderson cascade impaction studies. The prepared formulations effectively releases drug for 12 h in diffusion bag studies. Based on dissolution performance the 1:1 ratio of salbutamol sulphate:poly (D,L-lactic-co-glycolic acid) produces in vitro release 92.57% at 12 h and having particle size of microparticles (D0.5μm) 5.02±0.6 and the pulmonary deposition of dry powder 34.5±3.21 (respiratory fraction in percentage). PMID:27168692

  3. Development of an Inhaled Sustained Release Dry Powder Formulation of Salbutamol Sulphate, an Antiasthmatic Drug.

    PubMed

    Kumaresan, C; Sathishkumar, K

    2016-01-01

    The present research was aimed to develop and characterize a sustained release dry powder inhalable formulation of salbutamol sulphate. The salbutamol sulphate microparticles were prepared by solvent evaporation method using biodegradable polymer poly (D,L-lactic-co-glycolic acid) to produce salbutamol sulphate microparticle mixed with carrier respirable grade lactose for oral inhalation of dry powder. The drug content were estimated to produce 1 mg sustained release salbutamol sulphate per dose. Total four formulations K1, K2, K3 and K4 were prepared with 1:1, 1:2, 1:3, 1:4 ratio of salbutamol sulphate:poly (D,L-lactic-co-glycolic acid). The developed formulations were studied for physicochemical properties, in vitro drug relase and Anderson cascade impaction studies. The prepared formulations effectively releases drug for 12 h in diffusion bag studies. Based on dissolution performance the 1:1 ratio of salbutamol sulphate:poly (D,L-lactic-co-glycolic acid) produces in vitro release 92.57% at 12 h and having particle size of microparticles (D0.5μm) 5.02±0.6 and the pulmonary deposition of dry powder 34.5±3.21 (respiratory fraction in percentage).

  4. A mild hand cleanser, alkyl ether sulphate supplemented with alkyl ether carboxylic acid and alkyl glucoside, improves eczema on the hand and prevents the growth of Staphylococcus aureus on the skin surface.

    PubMed

    Fukui, S; Morikawa, T; Hirahara, M; Terada, Y; Shimizu, M; Takeuchi, K; Takagi, Y

    2016-12-01

    Washing the hands using cleansers with antiseptic materials is the most popular method for hand hygiene and helps maintain health by preventing food poisoning and bacterial infections. However, repeated hand washing tends to induce eczema of the hand, such as dryness, cracking and erythema. Moreover, eczema on the hand leads to increased levels in Staphylococcus aureus (S. aureus) on the skin surface in contrast to expectations. Thus, mild hand cleansers which induce less eczema even with repeated washings are desired. Here, we evaluated the efficacy of a hand cleanser formulated with alkyl ether sulphate (AES), alkyl ether carboxylic acid (AEC) and alkyl glucoside (AG) that contains isopropyl methylphenol (IPMP) on skin symptoms and S. aureus levels. Eczema of the hand and the presence of S. aureus on the skin surface were analysed prior to and following 4 weeks of usage of the hand cleanser. A soap-based hand cleanser with IPMP was used as a reference cleanser. Eczema and cutaneous conditions were evaluated by visual grading, transepidermal water loss (TEWL), stratum corneum moisture-retention ability (MRA) and skin surface pH. The repeated use of the soap-based hand cleanser significantly worsened the hand dryness, scaling and cracks on the tips of the fingers and significantly increased the TEWL and decreased the MRA. In contrast, usage of the test cleanser only induced a significant increase in skin dryness but did not induce skin scaling or cracking and did not increase TEWL or decrease the MRA. Corresponding to these changes in skin symptoms, the presence of S. aureus increased the following use of the reference cleanser but not the test cleanser. There was no significant difference in skin surface pH between the two cleansers. Moreover, the increase in S. aureus was significantly correlated to the worsening of skin dryness and scaling. These results suggest that not only antimicrobial activity but also the mildness, which minimizes cutaneous effects

  5. Iron bioavailability in 8-24-month-old Thai children from a micronutrient-fortified quick-cooking rice containing ferric ammonium citrate or a mixture of ferrous sulphate and ferric sodium ethylenediaminetetraacetic acid.

    PubMed

    Chavasit, Visith; Porasuphatana, Suparat; Suthutvoravut, Umaporn; Zeder, Christroph; Hurrell, Richard

    2015-12-01

    A quick-cooking rice, produced from broken rice, is a convenient ingredient for complementary foods in Thailand. The rice is fortified with micronutrients including iron during the processing procedure, which can cause unacceptable sensory changes. A quick-cooking rice fortified with ferric ammonium citrate (FAC) or a mixture of ferrous sulphate (FeSO4 ) and ferric sodium ethylenediaminetetraacetic acid (NaFeEDTA), with a 2:1 molar ratio of iron from FeSO4  : iron from NaFeEDTA (FeSO4  + NaFeEDTA), gave a product that was organoleptically acceptable. The study compared iron absorption by infants and young children fed with micronutrient-fortified quick-cooking rice containing the test iron compounds or FeSO4 . Micronutrient-fortified quick-cooking rice prepared as a traditional Thai dessert was fed to two groups of 15 8-24-month healthy Thai children. The iron fortificants were isotopically labelled with (57) Fe for the reference FeSO4 or (58) Fe for the tested fortificants, and iron absorption was quantified based on erythrocyte incorporation of the iron isotopes 14 days after feeding. The relative bioavailability of FAC and of the FeSO4  + NaFeEDTA was obtained by comparing their iron absorption with that of FeSO4 . Mean fractional iron absorption was 5.8% [±standard error (SE) 1.9] from FAC and 10.3% (±SE 1.9) from FeSO4  + NaFeEDTA. The relative bioavailability of FAC was 83% (P = 0.02). The relative bioavailability of FeSO4  + NaFeEDTA was 145% (P = 0.001). Iron absorption from the rice containing FAC or FeSO4  + NaFeEDTA was sufficiently high to be used in its formulation, although iron absorption from FeSO4  + NaFeEDTA was significantly higher (P < 0.00001). © 2015 John Wiley & Sons Ltd.

  6. Optimized Extraction Method To Remove Humic Acid Interferences from Soil Samples Prior to Microbial Proteome Measurements.

    PubMed

    Qian, Chen; Hettich, Robert L

    2017-07-07

    The microbial composition and their activities in soil environments play a critical role in organic matter transformation and nutrient cycling. Liquid chromatography coupled to high-performance mass spectrometry provides a powerful approach to characterize soil microbiomes; however, the limited microbial biomass and the presence of abundant interferences in soil samples present major challenges to proteome extraction and subsequent MS measurement. To this end, we have designed an experimental method to improve microbial proteome measurement by removing the soil-borne humic substances coextraction from soils. Our approach employs an in situ detergent-based microbial lysis/TCA precipitation coupled to an additional cleanup step involving acidified precipitation and filtering at the peptide level to remove most of the humic acid interferences prior to proteolytic peptide measurement. The novelty of this approach is an integration to exploit two different characteristics of humic acids: (1) Humic acids are insoluble in acidic solution but should not be removed at the protein level, as undesirable protein removal may also occur. Rather it is better to leave the humics acids in the samples until the peptide level, at which point the significant differential solubility of humic acids versus peptides at low pH can be exploited very efficiently. (2) Most of the humic acids have larger molecule weights than the peptides. Therefore, filtering a pH 2 to 3 peptide solution with a 10 kDa filter will remove most of the humic acids. This method is easily interfaced with normal proteolytic processing approaches and provides a reliable and straightforward protein extraction method that efficiently removes soil-borne humic substances without inducing proteome sample loss or biasing protein identification in mass spectrometry. In general, this humic acid removal step is universal and can be adopted by any workflow to effectively remove humic acids to avoid them negatively competing

  7. Cultivation of an obligate acidophilic ammonia oxidizer from a nitrifying acid soil.

    PubMed

    Lehtovirta-Morley, Laura E; Stoecker, Kilian; Vilcinskas, Andreas; Prosser, James I; Nicol, Graeme W

    2011-09-20

    Nitrification is a fundamental component of the global nitrogen cycle and leads to significant fertilizer loss and atmospheric and groundwater pollution. Nitrification rates in acidic soils (pH < 5.5), which comprise 30% of the world's soils, equal or exceed those of neutral soils. Paradoxically, autotrophic ammonia oxidizing bacteria and archaea, which perform the first stage in nitrification, demonstrate little or no growth in suspended liquid culture below pH 6.5, at which ammonia availability is reduced by ionization. Here we report the discovery and cultivation of a chemolithotrophic, obligately acidophilic thaumarchaeal ammonia oxidizer, "Candidatus Nitrosotalea devanaterra," from an acidic agricultural soil. Phylogenetic analysis places the organism within a previously uncultivated thaumarchaeal lineage that has been observed in acidic soils. Growth of the organism is optimal in the pH range 4 to 5 and is restricted to the pH range 4 to 5.5, unlike all previously cultivated ammonia oxidizers. Growth of this organism and associated ammonia oxidation and autotrophy also occur during nitrification in soil at pH 4.5. The discovery of Nitrosotalea devanaterra provides a previously unsuspected explanation for high rates of nitrification in acidic soils, and confirms the vital role that thaumarchaea play in terrestrial nitrogen cycling. Growth at extremely low ammonia concentration (0.18 nM) also challenges accepted views on ammonia uptake and metabolism and indicates novel mechanisms for ammonia oxidation at low pH.

  8. Cultivation of an obligate acidophilic ammonia oxidizer from a nitrifying acid soil

    PubMed Central

    Lehtovirta-Morley, Laura E.; Stoecker, Kilian; Vilcinskas, Andreas; Prosser, James I.; Nicol, Graeme W.

    2011-01-01

    Nitrification is a fundamental component of the global nitrogen cycle and leads to significant fertilizer loss and atmospheric and groundwater pollution. Nitrification rates in acidic soils (pH < 5.5), which comprise 30% of the world's soils, equal or exceed those of neutral soils. Paradoxically, autotrophic ammonia oxidizing bacteria and archaea, which perform the first stage in nitrification, demonstrate little or no growth in suspended liquid culture below pH 6.5, at which ammonia availability is reduced by ionization. Here we report the discovery and cultivation of a chemolithotrophic, obligately acidophilic thaumarchaeal ammonia oxidizer, “Candidatus Nitrosotalea devanaterra,” from an acidic agricultural soil. Phylogenetic analysis places the organism within a previously uncultivated thaumarchaeal lineage that has been observed in acidic soils. Growth of the organism is optimal in the pH range 4 to 5 and is restricted to the pH range 4 to 5.5, unlike all previously cultivated ammonia oxidizers. Growth of this organism and associated ammonia oxidation and autotrophy also occur during nitrification in soil at pH 4.5. The discovery of Nitrosotalea devanaterra provides a previously unsuspected explanation for high rates of nitrification in acidic soils, and confirms the vital role that thaumarchaea play in terrestrial nitrogen cycling. Growth at extremely low ammonia concentration (0.18 nM) also challenges accepted views on ammonia uptake and metabolism and indicates novel mechanisms for ammonia oxidation at low pH. PMID:21896746

  9. Sultr4;1 mutant seeds of Arabidopsis have an enhanced sulphate content and modified proteome suggesting metabolic adaptations to altered sulphate compartmentalization

    PubMed Central

    2010-01-01

    Background Sulphur is an essential macronutrient needed for the synthesis of many cellular components. Sulphur containing amino acids and stress response-related compounds, such as glutathione, are derived from reduction of root-absorbed sulphate. Sulphate distribution in cell compartments necessitates specific transport systems. The low-affinity sulphate transporters SULTR4;1 and SULTR4;2 have been localized to the vacuolar membrane, where they may facilitate sulphate efflux from the vacuole. Results In the present study, we demonstrated that the Sultr4;1 gene is expressed in developing Arabidopsis seeds to a level over 10-fold higher than the Sultr4;2 gene. A characterization of dry mature seeds from a Sultr4;1 T-DNA mutant revealed a higher sulphate content, implying a function for this transporter in developing seeds. A fine dissection of the Sultr4;1 seed proteome identified 29 spots whose abundance varied compared to wild-type. Specific metabolic features characteristic of an adaptive response were revealed, such as an up-accumulation of various proteins involved in sugar metabolism and in detoxification processes. Conclusions This study revealed a role for SULTR4;1 in determining sulphate content of mature Arabidopsis seeds. Moreover, the adaptive response of sultr4;1 mutant seeds as revealed by proteomics suggests a function of SULTR4;1 in redox homeostasis, a mechanism that has to be tightly controlled during development of orthodox seeds. PMID:20426829

  10. H-binding groups in lignite vs. soil humic acids: NICA-Donnan and spectroscopic parameters

    SciTech Connect

    Drosos, M.; Jerzykiewicz, M.; Deligiannakis, Y.

    2009-04-15

    A comparative study has been carried out for two sets of humic acids isolated from lignites and soils. H-binding data were analyzed using the NICA-Donnan model, for three Greek lignite humic acids (HA) plus IHSS Leonardite reference HA, and five Greek soil HAs plus a commercial peat HA. {sup 13}C-CP-MAS NMR and H-binding data provide quantitative estimates for functional groups, showing that lignite HAs of diverse origin have strikingly homogeneous properties, while the H-binding structural units of soil HAs are characterized by a large degree of variability. Consistent differences between soil HA vs. lignite HA are revealed at the level of functional groups' concentrations. In the pH range 4 to 10, soil HA showed a charge variation < 3 (equiv kg{sup -1}) while lignite HAs showed a higher charge variation > 3.5 (equiv kg{sup -1}).

  11. Influence of various concentrations of selenic acid (IV) on the activity of soil enzymes.

    PubMed

    Nowak, J; Kaklewski, K; Klódka, D

    2002-05-27

    The aim of this experiment was the assessment of the influence of various concentrations of H2SeO3 (0.05, 0.5 and 5 mM) on the activity of soil enzymes over 112 days. The lab experiment was performed using soil samples (dust-silt black soil of 1.92% organic C content, pH 7.7), 60% maximal water capacity. The soil samples were treated with a selenic acid water solution at the concentrations mentioned above. As a reference, natural soil was used (without the selenic acid). The activity of the following enzymes was tested: beta-glucosidase, nitrate reductase, urease, dehydrogenase, acid and alkaline phosphatases. The soil was sampled at days 0, 1, 3, 7, 14, 28, 56 and 112. The results of the study have shown that the selenic acid had no effect on the activity of the beta-glucosidase in soil. In the course of the whole experiment, the applied selenic acid inhibited activity of the nitrate reductase up to 70% at 5 mM, and the activity of dehydrogenase was also decreased--by up to 85% at 5 mM, similarly to urease (with the exception of days 14 and 28), and acid phosphatase (until day 56). The activity of alkaline phosphatase was increased by the lowest concentration of selenic acid and decreased by the highest, which was found in the course of the whole experiment. The 5-mM concentration of selenic acid inhibited the activity of all the enzymes tested in this experiment.

  12. What can legacy datasets tell us about soil quality trends? Soil acidity in Victoria

    NASA Astrophysics Data System (ADS)

    Marchant, B. P.; Crawford, D. M.; Robinson, N. J.

    2015-07-01

    Purpose-built soil monitoring networks have been established in many countries to identify where soil functionality is threatened and to target remediation initiatives. An alternative to purpose-built soil monitoring networks is to use legacy soils information. Such information yields almost instant assessments of soil change but the results should be interpreted with caution since the information was not collected with monitoring in mind. We assess the threat of soil acidification in Victoria using two legacy datasets: (i) the Victorian Soils Information System (VSIS) which is a repository of the results of soil analyses conducted for scientific purposes since the 1950s and (ii) a database of 75 000 routine soil test results requested by farmers between 1973 and 1993. We find that the VSIS measurements are clustered in space and time and are therefore suitable for local rather than broad-scale assessments of soil change. The farmers’ results have better spatial and temporal coverage and space-time models can be used to quantify the spatial and temporal trends in the pH measurements. However, careful validation of these findings is required since we do not completely understand how the measured paddocks were selected and we cannot be certain that sampling or laboratory protocols have not changed with time.

  13. Prolonged acid rain facilitates soil organic carbon accumulation in a mature forest in Southern China.

    PubMed

    Wu, Jianping; Liang, Guohua; Hui, Dafeng; Deng, Qi; Xiong, Xin; Qiu, Qingyan; Liu, Juxiu; Chu, Guowei; Zhou, Guoyi; Zhang, Deqiang

    2016-02-15

    With the continuing increase in anthropogenic activities, acid rain remains a serious environmental threat, especially in the fast developing areas such as southern China. To detect how prolonged deposition of acid rain would influence soil organic carbon accumulation in mature subtropical forests, we conducted a field experiment with simulated acid rain (SAR) treatments in a monsoon evergreen broadleaf forest at Dinghushan National Nature Reserve in southern China. Four levels of SAR treatments were set by irrigating plants with water of different pH values: CK (the control, local lake water, pH ≈ 4.5), T1 (water pH=4.0), T2 (water pH=3.5), and T3 (water pH=3.0). Results showed reduced pH measurements in the topsoil exposed to simulated acid rains due to soil acidification. Soil respiration, soil microbial biomass and litter decomposition rates were significantly decreased by the SAR treatments. As a result, T3 treatment significantly increased the total organic carbon by 24.5% in the topsoil compared to the control. Furthermore, surface soil became more stable as more recalcitrant organic matter was generated under the SAR treatments. Our results suggest that prolonged acid rain exposure may have the potential to facilitate soil organic carbon accumulation in the subtropical forest in southern China. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Interactions of aluminum with forest soils and vegetation: Implications for acid deposition

    SciTech Connect

    Maynard, A.A.

    1989-01-01

    Recent evidence suggests that an important ecological consequence of acidic deposition is increased aluminum mobilization. There is concern that increased aluminum activity may produce toxic effects in forested ecosystems. My studies were concerned with the behavior of pedogenic and added aluminum in soils derived from chemically different parent material. Soil aluminum was related to the aluminum content of the vegetation found growing in the soils. In addition, aluminum levels of forest litter was compared to levels determined 40 years ago. Field, greenhouse, and laboratory investigations were conducted in which the effects of aluminum concentration on germination and early growth was determined. Soils were then used in greenhouse and laboratory studies to establish patterns of soil and plant aluminum behavior with implications to acid deposition. Results show that the amount of aluminum extracted was related to the pH value of the extracting solution and to the chemical characteristics of the soil. Some acid rain solutions extracted measurable amounts of aluminum from selected primary minerals. Germination and early growth of Pinus radiata was controlled by levels of aluminum in the soil or in solution. Field studies indicated that most forest species were sensitive to rising levels of aluminum in the soil. In general, ferns and fern allies were less sensitive to very high levels of aluminum in the soil, continuing to grow when more advanced dicots have disappeared. Aluminum tissue levels of all species were related to the concentration of aluminum in the soil as was the reappearance of species. Aluminum levels in leaf litter have risen at least 50% in the last 40 years. These values were consistent over 3 years. The implications to acid deposition were discussed.

  15. The effect of organic acid on the spectral-induced polarization response of soil

    NASA Astrophysics Data System (ADS)

    Schwartz, N.; Shalem, T.; Furman, A.

    2014-04-01

    In spectral-induced polarization (SIP) studies of sites contaminated by organic hydrocarbons, it was shown that biodegradation by-products in general, and organic acids in particular, significantly alter the SIP signature of the subsurface. Still a systematic study that considers the effect of organic acid on the physicochemical and electrical (SIP) properties of the soil is missing. The goal of this work is to relate between the effect of organic acid on the physicochemical properties of the soil, and the soil electrical properties. To do so, we measured the temporal changes of the soil chemical (ion content) and electrical (low-frequency SIP) properties in response to influx of organic acid at different concentrations, gradually altering the soil pH. Our results show that organic acid reduces the soil pH, enhances mineral weathering and consequently reduces both the in-phase and quadrature conductivity. At the pH range where mineral weathering is most significant (pH 6-4.5) a negative linear relation between the soil pH and the soil formation factor was found, suggesting that mineral weathering changes the pore space geometry and hence affecting the in-phase electrical conductivity. In addition, we attribute the reduction in the quadrature conductivity to an exchange process between the natural cation adsorbed on the mineral surface and hydronium, and to changes in the width of the pore bottleneck that results from the mineral weathering. Overall, our results allow a better understanding of the SIP signature of soil undergoing acidification process in general and as biodegradation process in particular.

  16. Response of soil respiration to acid rain in forests of different maturity in southern China.

    PubMed

    Liang, Guohua; Liu, Xingzhao; Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  17. Response of Soil Respiration to Acid Rain in Forests of Different Maturity in Southern China

    PubMed Central

    Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types. PMID:23626790

  18. Ferrous sulphate interacts with captopril

    PubMed Central

    Schaefer, J P; Tam, Y; Hasinoff, B B; Tawfik, S; Peng, Y; Reimche, L; Campbell, N R C

    1998-01-01

    Aims To determine if iron binds strongly to captopril and reduces captopril absorption. Methods A variety of in vitro experiments was conducted to examine iron binding to captopril and a randomized, double-blind, placebo controlled, cross-over study design was used to assess the in vivo interaction. Captopril (25 mg) was coingested with either ferrous sulphate (300 mg) or placebo by seven healthy adult volunteers. Subjects were phlebotomized and had blood pressure measured at 0, 0.25, 0.5, 1, 2, 4, 6, 8, and 12 h post ingestion. A 1 week washout period was used. Results The coingestion of ferrous sulphate and captopril was associated with a 37% (134 ng ml−1 h, 95% CI 41–228 ng ml−1 h, P=0.03) decrease in area under the curve (AUC) for unconjugated plasma captopril. There were no substantial changes in Cmax (mean difference;–32; 95% CI −124–62 ng ml−1(P=0.57)) or in tmax (mean difference; 0; 95% CI −18–18 min (P=0.65)) for unconjugated captopril when captopril was ingested with iron. There was a statistically insignificant increase in AUC for total plasma captopril of 43% (1312 ng ml−1 h, 95% CI −827–3451 ng ml−1 h P=0.27) when captopril was ingested with iron. The addition of ferric chloride to captopril resulted in the initial rapid formation of a soluble blue complex which rapidly disappeared to be replaced by a white precipitant. The white precipitate was identified as captopril disulphide dimer. There were no significant differences in systolic and diastolic blood pressures between the treatment and placebo groups. Conclusions Co-administration of ferrous sulphate and iron results in decreased unconjugated captopril levels likely due to a chemical interaction between ferric ion and captopril in the gastrointestinal tract. Care is required when coprescribing captopril and iron salts. PMID:9803987

  19. Magnesium sulphate salts and the history of water on Mars.

    PubMed

    Vaniman, David T; Bish, David L; Chipera, Steve J; Fialips, Claire I; Carey, J William; Feldman, William C

    2004-10-07

    Recent reports of approximately 30 wt% of sulphate within saline sediments on Mars--probably occurring in hydrated form--suggest a role for sulphates in accounting for equatorial H2O observed in a global survey by the Odyssey spacecraft. Among salt hydrates likely to be present, those of the MgSO4*nH2O series have many hydration states. Here we report the exposure of several of these phases to varied temperature, pressure and humidity to constrain their possible H2O contents under martian surface conditions. We found that crystalline structure and H2O content are dependent on temperature-pressure history, that an amorphous hydrated phase with slow dehydration kinetics forms at <1% relative humidity, and that equilibrium calculations may not reflect the true H2O-bearing potential of martian soils. Mg sulphate salts can retain sufficient H2O to explain a portion of the Odyssey observations. Because phases in the MgSO4*nH2O system are sensitive to temperature and humidity, they can reveal much about the history of water on Mars. However, their ease of transformation implies that salt hydrates collected on Mars will not be returned to Earth unmodified, and that accurate in situ analysis is imperative.

  20. Magnesium sulphate salts and the history of water on Mars

    NASA Astrophysics Data System (ADS)

    Vaniman, David T.; Bish, David L.; Chipera, Steve J.; Fialips, Claire I.; William Carey, J.; Feldman, William C.

    2004-10-01

    Recent reports of ~30wt% of sulphate within saline sediments on Mars-probably occurring in hydrated form-suggest a role for sulphates in accounting for equatorial H2O observed in a global survey by the Odyssey spacecraft. Among salt hydrates likely to be present, those of the MgSO4.nH2O series have many hydration states. Here we report the exposure of several of these phases to varied temperature, pressure and humidity to constrain their possible H2O contents under martian surface conditions. We found that crystalline structure and H2O content are dependent on temperature-pressure history, that an amorphous hydrated phase with slow dehydration kinetics forms at <1% relative humidity, and that equilibrium calculations may not reflect the true H2O-bearing potential of martian soils. Mg sulphate salts can retain sufficient H2O to explain a portion of the Odyssey observations. Because phases in the MgSO4.nH2O system are sensitive to temperature and humidity, they can reveal much about the history of water on Mars. However, their ease of transformation implies that salt hydrates collected on Mars will not be returned to Earth unmodified, and that accurate in situ analysis is imperative.

  1. Comparison of solvent mixtures for pressurized solvent extraction of soil fatty acid biomarkers.

    PubMed

    Jeannotte, Richard; Hamel, Chantal; Jabaji, Suha; Whalen, Joann K

    2008-10-19

    The extraction and transesterification of soil lipids into fatty acid methyl esters (FAMEs) is a useful technique for studying soil microbial communities. The objective of this study was to find the best solvent mixture to extract soil lipids with a pressurized solvent extractor system. Four solvent mixtures were selected for testing: chloroform:methanol:phosphate buffer (1:2:0.8, v/v/v), chloroform:methanol (1:2, v/v), hexane:2-propanol (3:2, v/v) and acetone. Soils were from agricultural fields and had a wide range of clay, organic matter and microbial biomass contents. Total lipid fatty acid methyl esters (TL-FAMEs) were the extractable soil lipids identified and quantified with gas chromatography and flame ionization detection. Concentrations of TL-FAMEs ranged from 57.3 to 542.2 nmole g(-1) soil (dry weight basis). The highest concentrations of TL-FAMEs were extracted with chloroform:methanol:buffer or chloroform:methanol mixtures than with the hexane:2-propanol or acetone solvents. The concentrations of TL-FAMEs in chemical groups, including saturated, branched, mono- and poly-unsaturated and hydroxy fatty acids were assessed, and biological groups (soil bacteria, mycorrhizal fungi, saprophytic fungi and higher plants) was distinguished. The extraction efficiency for the chemical and biological groups followed the general trend of: chloroform:methanol:buffer> or =chloroform:methanol>hexane:2-propanol=acetone. Discriminant analysis revealed differences in TL-FAME profiles based on the solvent mixture and the soil type. Although solvent mixtures containing chloroform and methanol were the most efficient for extracting lipids from the agricultural soils in this study, soil properties and the lipid groups to be studied should be considered when selecting a solvent mixture. According to our knowledge, this is the first report of soil lipid extraction with hexane:2-propanol or acetone in a pressurized solvent extraction system.

  2. Assessment of bioavailable organic phosphorus in tropical forest soils by organic acid extraction and phosphatase hydrolysis.

    PubMed

    Darch, Tegan; Blackwell, Martin S A; Chadwick, David; Haygarth, Philip M; Hawkins, Jane M B; Turner, Benjamin L

    2016-12-15

    Soil organic phosphorus contributes to the nutrition of tropical trees, but is not accounted for in standard soil phosphorus tests. Plants and microbes can release organic anions to solubilize organic phosphorus from soil surfaces, and synthesize phosphatases to release inorganic phosphate from the solubilized compounds. We developed a procedure to estimate bioavailable organic phosphorus in tropical forest soils by simulating the secretion processes of organic acids and phosphatases. Five lowland tropical forest soils with contrasting properties (pH 4.4-6.1, total P 86-429 mg P kg(- 1)) were extracted with 2 mM citric acid (i.e., 10 μmol g(- 1), approximating rhizosphere concentrations) adjusted to soil pH in a 4:1 solution to soil ratio for 1 h. Three phosphatase enzymes were then added to the soil extract to determine the forms of hydrolysable organic phosphorus. Total phosphorus extracted by the procedure ranged between 3.22 and 8.06 mg P kg(- 1) (mean 5.55 ± 0.42 mg P kg(- 1)), of which on average three quarters was unreactive phosphorus (i.e., organic phosphorus plus inorganic polyphosphate). Of the enzyme-hydrolysable unreactive phosphorus, 28% was simple phosphomonoesters hydrolyzed by phosphomonoesterase from bovine intestinal mucosa, a further 18% was phosphodiesters hydrolyzed by a combination of nuclease from Penicillium citrinum and phosphomonoesterase, and the remaining 51% was hydrolyzed by a broad-spectrum phytase from wheat. We conclude that soil organic phosphorus can be solubilized and hydrolyzed by a combination of organic acids and phosphatase enzymes in lowland tropical forest soils, indicating that this pathway could make a significant contribution to biological phosphorus acquisition in tropical forests. Furthermore, we have developed a method that can be used to assess the bioavailability of this soil organic phosphorus.

  3. [Nitrate nitrogen leaching and residue of humic acid fertilizer in field soil].

    PubMed

    Liu, Fang-chun; Xing, Shang-jun; Duan, Chun-hua; Du, Zhen-yu; Ma, Hai-lin; Ma, Bing-yao

    2010-07-01

    To elucidate the potential influence of humic acidfertilizer on groundwater and soil quality in clay soil (CS) and sandy soil (SS), nitrate nitrogen leaching and residue of different fertilizers in field soil were studied using a self-made leaching field device. Nitrate nitrogen concentration in leaching water of fertilizer treatments was 28.1%-222.2% higher than that of non-nitrogen treatment in different times, but humic acid fertilizer could prevent nitrate nitrogen leaching both in CS and SS, especially in CS. Nitrate nitrogen concentration of leaching water in CS was 41.2%-59.1% less than that in SS and the inhibiting effect in CS was greater than that in SS. Nitrate nitrogen could be accumulated in soil profile by fertilizer application. The residue of nitrate nitrogen retained in 0-40 cm soil layer of humic acid fertilizer treatment was 59.8% and 54.4% respectively, higher than that of urea and compound fertilizer treatments. Nitrate nitrogen amount of humic acid, urea and compound fertilizer treatments in SS was significantly less than that in CS, being 81.7%, 81.1% and 47.6% respectively. Compared with the conventional fertilizer, humic acid fertilizer treatment improved the contents of organic matter, available nitrogen, phosphorus, and potassium of upper layer soil as well as cation exchange capacity. Besides, total amount of water-soluble salts in humic acid fertilizer treatment was decreased by 24.8% and 22.5% in comparison to urea and compound fertilizer treatments in CS, respectively. In summary, the application of humic acid fertilizer could improve physical and chemical properties of upper layer soil and reduce the risk of potential pollution to groundwater.

  4. Cadmium solubility and bioavailability in soils amended with acidic and neutral biochar.

    PubMed

    Qi, Fangjie; Lamb, Dane; Naidu, Ravi; Bolan, Nanthi S; Yan, Yubo; Ok, Yong Sik; Rahman, Mohammad Mahmudur; Choppala, Girish

    2018-01-01

    This study was designed to investigate the effects of acidic and neutral biochars on solubility and bioavailability of cadmium (Cd) in soils with contrasting properties. Four Cd contaminated (50mg/kg) soils (EN: Entisol, AL: Andisol, VE: Vertisol, IN: Inceptisol) were amended with 5% acidic wood shaving biochar (WS, pH=3.25) and neutral chicken litter biochar (CL, pH=7.00). Following a 140-day incubation, the solubility and bioavailability/bioaccessibility of cadmium (Cd) were assessed. Results showed that both biochars had no effect on reducing soluble (pore water) and bioavailable (CaCl2 extractable) Cd for higher sorption capacity soils (AL, IN) while CL biochar reduced those in lower sorption capacity soils (EN, VE) by around 50%. Bioaccessibility of Cd to the human gastric phase (physiologically based extraction test (PBET) extractable) was not altered by the acidic WS biochar but reduced by neutral CL biochar by 18.8%, 29.7%, 18.0% and 8.82% for soil AL, EN, IN and VE, respectively. Both biochars reduced soluble Cd under acidic conditions (toxicity characteristic leaching procedure (TCLP) extractable) significantly in all soils. Pore water pH was the governing factor of Cd solubility among soils. The reduction of Cd solubility and bioavailability/bioaccessibility by CL biochar may be due to surface complexation while the reduced mobility of Cd under acidic conditions (TCLP) by both biochars may result from the redistribution of Cd to less bioavailable soil solid fractions. Hence, if only leaching mitigation of Cd under acidic conditions is required, application of low pH biochars (e.g., WS biochar) may be valuable. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Acid sulfate soils and human health--a Millennium Ecosystem Assessment.

    PubMed

    Ljung, Karin; Maley, Fiona; Cook, Angus; Weinstein, Philip

    2009-11-01

    Acid sulfate soils have been described as the "nastiest soils on earth" because of their strong acidity, increased mobility of potentially toxic elements and limited bioavailability of nutrients. They only cover a small area of the world's total problem soils, but often have significant adverse effects on agriculture, aquaculture and the environment on a local scale. Their location often coincides with high population density areas along the coasts of many developing countries. As a result, their negative impacts on ecosystems can have serious implications to those least equipped for coping with the low crop yields and reduced water quality that can result from acid sulfate soil disturbance. The Millennium Ecosystem Assessment called on by the United Nations in 2000 emphasised the importance of ecosystems for human health and well-being. These include the service they provide as sources of food and water, through the control of pollution and disease, as well as for the cultural services ecosystems provide. While the problems related to agriculture, aquaculture and the environment have been the focus of many acid sulfate soil management efforts, the connection to human health has largely been ignored. This paper presents the potential health issues of acid sulfate soils, in relation to the ecosystem services identified in the Millennium Ecosystem Assessment. It is recognised that significant implications on food security and livelihood can result, as well as on community cohesiveness and the spread of vector-borne disease. However, the connection between these outcomes and acid sulfate soils is often not obvious and it is therefore argued that the impact of such soils on human well-being needs to be recognised in order to raise awareness among the public and decision makers, to in turn facilitate proper management and avoid potential human ill-health.

  6. Estimates of critical acid loads and exceedances for forest soils across the conterminous United States

    Treesearch

    Steven G. McNulty; Erika C. Cohen; Jennifer A. Moore Myers; Timothy J. Sullivan; Harbin Li

    2007-01-01

    Concern regarding the impacts of continued nitrogen and sulfur deposition on ecosystem health has prompted the development of critical acid load assessments for forest soils. A critical acid load is a quantitative estimate of exposure to one or more pollutants at or above which harmful acidification-related effects on sensitive elements of the environment occur. A...

  7. Determination of the D and L isomers of some protein amino acids present in soils

    NASA Technical Reports Server (NTRS)

    Pollock, G. E.; Cheng, C.-N.; Cronin, S. E.

    1977-01-01

    The D and L isomers of some protein amino acids present in soils were measured by using a gas chromatographic technique. The results of two processing procedures were compared to determine the better method. Results of the comparison indicated that the determination of D and L percentages requires amino acid purification if one is to obtain accurate data. It was found that very significant amounts of D-alanine, D-aspartic acid, and D-glutamic acid were present in the contemporary soils studied. Valine, isoleucine, leucine, proline, and phenylalanine generally contained only a trace to very small amounts of the D isomer. It is probable that the D-amino acids from the alanine, aspartic, and glutamic acids are contributed to the soil primarily via microorganisms. The finding of very significant quantities of some D-amino acids (about 5-16%) in present-day soils may alert some investigators of geological sediments to a possible problem in using amino acid racemization as an age-dating technique.

  8. [Determination of 13C enrichment in soil amino acid enantiomers by gas chromatogram/mass spectrometry].

    PubMed

    He, Hong-Bo; Zhang, Wei; Ding, Xue-Li; Bai, Zhen; Liu, Ning; Zhang, Xu-Dong

    2008-06-01

    The transformation and renewal of amino acid enantiomers is of significance in indicating the turnover mechanism of soil organic matter. In this paper, a method of gas chromatogram/mass spectrometry combined with U-13 C-glucose incubation was developed to determine the 13C enrichment in soil amino acid enantiomers, which could effectively differentiate the original and the newly synthesized amino acids in soil matrix. The added U-13 C-glucose was utilized rapidly to structure the amino acid carbon skeleton, and the change of relative abundance of isotope ions could be determined by mass spectrometry. The direct incorporation of U-13 C glucose was estimated by the intensity increase of m/z (F + n) to F (F was parent fragment, and n was the carbon number in the fragment), while the total isotope incorporation from the added 13C could be calculated according to the abundance ratio increment summation from m/z (Fa + 1) through (Fa + T) (Fa was the fragment containing all original skeleton carbons, and T was the carbon number in the amino acid molecule). The 13C enrichment in the target compound was expressed as atom percentage excess (APE), and that of D-amino acid needed to be corrected by the coefficient of hydrolysis-induced racemization. The 13C enrichment reflected the carbon turnover velocity of individual amino acid enantiomers, and was powerful to investigate the dynamics of soil amino acids.

  9. Impact of mitigation strategies on acid sulfate soil chemistry and microbial community.

    PubMed

    Wu, Xiaofen; Sten, Pekka; Engblom, Sten; Nowak, Pawel; Österholm, Peter; Dopson, Mark

    2015-09-01

    Potential acid sulfate soils contain reduced iron sulfides that if oxidized, can cause significant environmental damage by releasing large amounts of acid and metals. This study examines metal and acid release as well as the microbial community capable of catalyzing metal sulfide oxidation after treating acid sulfate soil with calcium carbonate (CaCO3) or calcium hydroxide (Ca(OH)2). Leaching tests of acid sulfate soil samples were carried out in the laboratory. The pH of the leachate during the initial flushing with water lay between 3.8 and 4.4 suggesting that the jarosite/schwertmannite equilibrium controls the solution chemistry. However, the pH increased to circa 6 after treatment with CaCO3 suspension and circa 12 after introducing Ca(OH)2 solution. 16S rRNA gene sequences amplified from community DNA extracted from the untreated and both CaCO3 and Ca(OH)2 treated acid sulfate soils were most similar to bacteria (69.1% to 85.7%) and archaea (95.4% to 100%) previously identified from acid and metal contaminated environments. These species included a Thiomonas cuprina-like and an Acidocella-like bacteria as well as a Ferroplasma acidiphilum-like archeon. Although the CaCO3 and Ca(OH)2 treatments did not decrease the proportion of microorganisms capable of accelerating acid and metal release, the chemical effects of the treatments suggested their reduced activity.

  10. Nucleic Acid Extraction from Synthetic Mars Analog Soils for in situ Life Detection.

    PubMed

    Mojarro, Angel; Ruvkun, Gary; Zuber, Maria T; Carr, Christopher E

    2017-08-01

    Biological informational polymers such as nucleic acids have the potential to provide unambiguous evidence of life beyond Earth. To this end, we are developing an automated in situ life-detection instrument that integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG) instrument. Our goal is to isolate and determine the sequence of nucleic acids from extant or preserved life on Mars, if, for example, there is common ancestry to life on Mars and Earth. As is true of metagenomic analysis of terrestrial environmental samples, the SETG instrument must isolate nucleic acids from crude samples and then determine the DNA sequence of the unknown nucleic acids. Our initial DNA extraction experiments resulted in low to undetectable amounts of DNA due to soil chemistry-dependent soil-DNA interactions, namely adsorption to mineral surfaces, binding to divalent/trivalent cations, destruction by iron redox cycling, and acidic conditions. Subsequently, we developed soil-specific extraction protocols that increase DNA yields through a combination of desalting, utilization of competitive binders, and promotion of anaerobic conditions. Our results suggest that a combination of desalting and utilizing competitive binders may establish a "universal" nucleic acid extraction protocol suitable for analyzing samples from diverse soils on Mars. Key Words: Life-detection instruments-Nucleic acids-Mars-Panspermia. Astrobiology 17, 747-760.

  11. Early indications of soil recovery from acidic deposition in U.S. red spruce forests

    USGS Publications Warehouse

    Lawrence, Gregory B.; Shortle, Walter C.; David, Mark B.; Smith, Kevin T.; Warby, Richard A.F.; Lapenis, Andrei G.

    2012-01-01

    Forty to fifty percent decreases in acidic deposition through the 1980s and 1990s led to partial recovery of acidified surface waters in the northeastern United States; however, the limited number of studies that have assessed soil change found increased soil acidification during this period. From existing data, it's not clear whether soils continued to worsen in the 1990s or if recovery had begun. To evaluate possible changes in soils through the 1990s, soils in six red spruce (Picea rubens Sarg.) stands in New York, Vermont, New Hampshire, and Maine, first sampled in 1992 to 1993, were resampled in 2003 to 2004. The Oa-horizon pH increased (P 42−, which decreased the mobility of Al throughout the upper soil profile. Results indicate a nascent recovery driven largely by vegetation processes.

  12. Simultaneous adsorption/desorption of quaternary ammonium herbicides by acid vineyard soils

    NASA Astrophysics Data System (ADS)

    Conde Cid, Manuel; Paradelo Núñez, Remigio; Fernández Calviño, David; Nóvoa Muñoz, Juan Carlos; Arias Estévez, Manuel

    2017-04-01

    Competitive adsorption and desorption of three quaternary ammonium herbicides (paraquat, diquat, and difenzoquat) have been studied in four sandy-loam acid vineyard soils from NW Spain and Portugal. The soils present organic matter contents between 3 and 48 g kg-1 and copper contents ranging from 25 to 107 mg kg-1. Adsorption has been studied under equilibrium conditions in batch experiments, and kinetics were studied in a stirred-flow chamber. Adsorption and desorption followed a Freundlich model and kinetics were well described by the pseudo-first-order model. The retention capacity for the pesticides by the four soils followed the sequence: paraquat > diquat > difenzoquat. The different adsorption capacities of each soil were not related to pH, clay or organic matter contents, as could be expected, but rather to soil copper content. The results show that competition with copper for adsorption sites is an important factor in quaternary ammonium herbicides retention in soils with these characteristics.

  13. Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids.

    PubMed

    Arwidsson, Zandra; Elgh-Dalgren, Kristin; von Kronhelm, Thomas; Sjöberg, Ragnar; Allard, Bert; van Hees, Patrick

    2010-01-15

    Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10-60 min. Nonetheless, after 10d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, would require a pre-leaching step lasting several days in order to be efficient.

  14. Physicochemical properties, cytotoxicity, and antimicrobial activity of sulphated zirconia nanoparticles

    PubMed Central

    Mftah, Ae; Alhassan, Fatah H; Al-Qubaisi, Mothanna Sadiq; El Zowalaty, Mohamed Ezzat; Webster, Thomas J; Sh-eldin, Mohammed; Rasedee, Abdullah; Taufiq-Yap, Yun Hin; Rashid, Shah Samiur

    2015-01-01

    Nanoparticle sulphated zirconia with Brønsted acidic sites were prepared here by an impregnation reaction followed by calcination at 600°C for 3 hours. The characterization was completed using X-ray diffraction, thermal gravimetric analysis, Fourier transform infrared spectroscopy, Brunner-Emmett-Teller surface area measurements, scanning electron microscopy with energy dispersive X-ray spectroscopy, and transmission electron microscopy. Moreover, the anticancer and antimicrobial effects were investigated for the first time. This study showed for the first time that the exposure of cancer cells to sulphated zirconia nanoparticles (3.9–1,000 μg/mL for 24 hours) resulted in a dose-dependent inhibition of cell growth, as determined by (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Similar promising results were observed for reducing bacteria functions. In this manner, this study demonstrated that sulphated zirconia nanoparticles with Brønsted acidic sites should be further studied for a wide range of anticancer and antibacterial applications. PMID:25632233

  15. Accumulation of different sulfur fractions in Chinese forest soil under acid deposition.

    PubMed

    Wang, Zhanyi; Zhang, Xiaoshan; Zhang, Yi; Wang, Zhangwei; Mulder, Jan

    2011-09-01

    Atmogenic sulfur (S) deposition loading by acid rain is one of the biggest environmental problems in China. It is important to know the accumulated S stored in soil, because eventually the size (and also the "desorption" rate) determines how rapidly the soil water pH responds to decrease in S deposition. The S fractions and the ratio of total carbon/total sulfur (C/S) of forest soil in 9 catchments were investigated by comparing soils at the rural and urban sites in China. The S fractions included water-soluble sulfate-S (SO(4)-S), adsorbed SO(4)-S, insoluble SO(4)-S and organic S. The ratio of C/S in soil at the rural site was significantly (p < 0.05) greater than that at the urban site. C/S of soil in the A horizon was significantly (p < 0.05) and negatively correlated with the wet S-deposition rate. The ratio of C/S presents a better indicator for atmogenic S loading. Organic S was the dominant form in soils at rural sites; contributing more than 69% of the total S in the uppermost 30 cm soil. Organic S and adsorbed SO(4)-S were the main forms of S in soil at urban sites. High contents of water-soluble SO(4)-S and adsorbed SO(4)-S were found in uppermost 30 cm soils at urban sites but not at rural sites. Decades of acid rain have caused accumulation of inorganic SO(4)-S in Chinese forest soil especially at the urban sites. The soil at urban sites had been firstly acidified, and the impacts on the forest ecosystem in these areas should be noticed.

  16. Ecosystem-specific selection of microbial ammonia oxidizers in an acid soil

    NASA Astrophysics Data System (ADS)

    Saiful Alam, M.; Ren, G.; Lu, L.; Zheng, Y.; Peng, X.; Jia, Z.

    2013-01-01

    The function of ammonia-oxidizing archaea (AOA) and bacteria (AOB) depends on the availability of ammonia substrate and the supply of oxygen. The interactions and evolutions of AOA and AOB communities along ecological gradients of substrate availability in complex environment have been much debated, but rarely tested. In this study, two ecosystems of maize and rice crops under different fertilization regimes were selected to investigate the community diversification of soil AOA and AOB in response to long-term field fertilization and flooding management in an acid soil. Real-time quantitative PCR of amoA genes demonstrated that the abundance of AOA was significantly stimulated after conversion of upland to paddy soils, while slight decline of AOB populations was observed. DGGE fingerprints of amoA genes further revealed remarkable changes in community compositions of AOA in paddy soil when compared to upland soil. Sequencing analysis revealed that upland soil was dominated by AOA within the soil group 1.1b lineage, while the marine group 1.1a lineage predominated AOA communities in paddy soils. Irrespective of upland and paddy soils, long-term field fertilizations led to higher abundance of amoA genes of AOA and AOB than control treatment that received no fertilization, whereas archaeal amoA gene abundances outnumbered their bacterial counterpart in all samples. Phylogenetic analyses of amoA genes showed that Nitrosospira cluster 3-like AOB dominated bacterial ammonia oxidizers in both paddy and upland soils, regardless of fertilization treatments. The results of this study suggest that the marine group 1.1a AOA could be better adapted to low-oxygen environment than AOA ecotypes of the soil group 1.1b lineage, and implicate that long-term flooding as the dominant selective force driving the community diversification of AOA populations in the acid soil tested.

  17. Understanding the mechanism behind the nitrous acid (HONO) emissions from the northern soils

    NASA Astrophysics Data System (ADS)

    Bhattarai, Hem Raj; Siljanen, Henri MP; Biasi, Christina; Maljanen, Marja

    2016-04-01

    The interest of the flux of nitrous acid (HONO) from soils has recently increased. HONO is an important source of the oxidant OH- radical in the troposphere and thus results a reduction of the greenhouse gas methane (CH4) in the atmosphere. Soils have been recently found to be potential sources of HONO as these emissions are linked to other nitrogen cycle processes, especially presence of nitrite in soils. Ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) have been suggested as possible yet substantial sources of HONO. Along with soil pH, other physical properties such as C:N, nitrogen availability, soil moisture and temperature may effect HONO emissions. Our preliminary results demonstrate that drained acidic peatlands with a low C:N produces higher NO, N2O and HONO emissions compared to those in pristine peatlands and upland forest soils. This study will identify the hotspots and the process involved in HONO emissions in northern ecosystems. Along with HONO, we will examine the emissions of NO and N2O to quantify the related N-gases emitted. These results will add a new piece of information in our knowledge of the nitrogen cycle. Soil samples will be collected from several boreal and arctic sites in Finland, Sweden and Russia. In the laboratory, soil samples will be manipulated based on previously described soil physical properties. This will be followed by labelling experiment coupled with selective nitrification inhibitor experiment in the soils. Our first hypothesis is that northern ecosystems are sources of HONO. Second, is that the soil properties (C:N ratio, moisture, N-availability, pH) regulate the magnitude of HONO emissions from northern soils. Third is that the first step of nitrification (ammonium oxidation) is the main pathway to produce HONO. This study will show that the northern ecosystems could be sources of HONO and therefore increasing the oxidizing capacity of the lower atmosphere.

  18. Studies of the compositions of humic acids from Amazonian Dark Earth soils.

    PubMed

    Novotny, Etelvino H; deAzevedo, Eduardo R; Bonagamba, Tito J; Cunha, Tony J F; Madari, Beáta E; de M Benites, Vinícius; Hayes, Michael H B

    2007-01-15

    The compositions of humic acids (HAs) isolated from cultivated and forested "Terra Preta de Indio" or Amazonian Dark Earth soils (anthropogenic soils) were compared with those from adjacent non-anthropogenic soils (control soils) using elemental and thermogravimetric analyses, and a variety of solid-state nuclear magnetic resonance techniques. The thermogravimetric index, which indicates the molecular thermal resistance, was greater for the anthropogenic soils than for the control soils suggesting polycyclic aromatic components in the former. The cultivated anthropogenic soils were more enriched in C and depleted in H than the anthropogenic soils under forest, as the result of the selective degradation of aliphatic structures and the possible enrichment of H-deficient condensed aromatic structures. The combination of variable amplitude cross-polarization (VACP) and chemical shift anisotropy with total suppression of spinning sidebands experiments with composite pi pulses could be used to quantify the aromaticity of the HAs from the anthropogenic soils. From principal component analysis, using the VACP spectra, it was possible to separate the different constituents of the HAs, such as the carboxylated aromatic structures, from the anthropogenic soils and plant derived compounds. The data show that the HAs from anthropogenic soils have high contents of aryl and ionisable oxygenated functional groups, and the major functionalities from adjacent control soils are oxygenated functional groups from labile structures (carbohydrates, peptides, and with evidence for lignin structures). The anthropogenic soils HAs can be considered to be more recalcitrant, and with more stable reactive functional groups which may, in part, explain their more sustainable fertility due to the organic matter contribution to the soil cation exchange capacity.

  19. Sulphate efflorescences at the geyser near Pinchollo, southern Peru

    NASA Astrophysics Data System (ADS)

    Ciesielczuk, Justyna; Żaba, Jerzy; Bzowska, Grażyna; Gaidzik, Krzysztof; Głogowska, Magdalena

    2013-03-01

    Sulphate mineralization precipitated around a geyser located above the village of Pinchollo, Chivay district and below Hualca Hualca volcano (6025 m a.s.l.) in the Western Cordillera of southern Peru is described. The geyser is one of many manifestations of thermal activity in the Arequipa department. Its age is estimated to be Upper Pleistocene-Holocene, as the discharge point lies at the intersection of a fault system with latitudinal dip-slip fault cutting a volcanic-debris avalanche of probably Pleistocene age. Thermal waters present in the Chivay district are mainly chloride-rich with a neutral pH. They are rich in Li, Sr, and B. The water erupting in the geyser boils at about 85 °C, as it lies at some 4353 m a.s.l. The minerals examined, of various habits and various yellow, orange and white colours were precipitated on the soil and on plants close to the geyser (location 1), on the walls of a 1 m diameter pothole filled with boiling water (location 1a) and at a distance of some 100 m to the west of the geyser (location 2). All are sulphates. Their chemical composition is fairly simple, consisting of Al, Fe, K, Mg, Ca, S, NH4 and O, and all display chemical zoning. But the phase composition is more complex. In all locations, alunogene, copiapite, coquimbite, tschermigite and gypsum are present. Close to the geyser (location 1) magnesium-containing sulphates, namely, boussingaultite and pickeringite also occur. Iron sulphates such as mohrite and rozenite precipitate on the walls of the pothole (location 1a). Sulphates containing potassium such as jarosite, alunite and voltaite-voltaite (Mg) dominate among the efflorescences in location 2, where hematite was also noted. Any quartz and kaolinite or illite/mica admixture identified in some samples derives from adjacent soil. The present geothermal system does not involve the deposition of precious-metal deposits such as those associated with an earlier deep-going epithermal system that scavenged a large volume

  20. Litter Decomposition in Low and High Mortality Northern Red Oak Stands on Extremely Acidic Southwestern Pennsylvania Soils

    Treesearch

    Michael C. Demchik; William E. Sharpe

    2004-01-01

    Previous research has shown that decomposition of organic matter is slower in soils with high levels of soil acidity and available aluminum (Al). The objective of this experiment was to determine if differences in decomposition rates of northern red oak leaves occurred between extremely acidic and less acidic sites that also differed in oak mortality. Leaf litter from...

  1. 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.

  2. Isolation and characterisation of putative adhesins from Helicobacter pylori with affinity for heparan sulphate proteoglycan.

    PubMed

    Ruiz-Bustos, E; Ochoa, J L; Wadström, T; Ascencio, F

    2001-03-01

    A pool of heparan sulphate-binding proteins (HSBPs) from Helicobacter pylori culture supernates was obtained by sequential ammonium sulphate precipitation and affinity chromatography on heparin-Sepharose. The chromatographic procedure yielded one major fraction that contained proteins with heparan sulphate affinity as revealed by inhibition studies of heparan sulphate binding to H. pylori cells. Preparative iso-electric focusing, SDS-PAGE and blotting experiments, with peroxidase(POD)-labelled heparan sulphate as a probe, indicated the presence of two major extracellular proteins with POD-heparan sulphate affinity. One protein had a molecular mass of 66.2 kDa and a pI of 5.4, whilst the second protein had a molecular mass of 71.5 kDa and a pI of 5.0. The N-terminal amino acid sequence of the 71.5-kDa HSBP did not show homology to any other heparin-binding protein, nor to known proteins of H. pylori, whereas the 66.2-kDa HSBP showed a high homology to an Escherichia coli chaperon protein and equine haemoglobin. A third HSBP was isolated from an outer-membrane protein (OMP) fraction of H. pylori cells with a molecular mass of 47.2 kDa. The amino acid sequence of an internal peptide of the OMP-HSBP did not show homology to the extracellular HSBP of H. pylori, or to another microbial HSBP.

  3. Rhizosheaths on wheat grown in acid soils: phosphorus acquisition efficiency and genetic control

    PubMed Central

    James, Richard A.; Weligama, Chandrakumara; Verbyla, Klara; Ryan, Peter R.; Rebetzke, Gregory J.; Rattey, Allan; Richardson, Alan E.; Delhaize, Emmanuel

    2016-01-01

    Rhizosheaths comprise soil bound to roots, and in wheat (Triticum aestivum L.) rhizosheath size correlates with root hair length. The aims of this study were to determine the effect that a large rhizosheath has on the phosphorus (P) acquisition by wheat and to investigate the genetic control of rhizosheath size in wheat grown on acid soil. Near-isogenic wheat lines differing in rhizosheath size were evaluated on two acid soils. The soils were fertilized with mineral nutrients and included treatments with either low or high P. The same soils were treated with CaCO3 to raise the pH and detoxify Al3+. Genotypic differences in rhizosheath size were apparent only when soil pH was low and Al3+ was present. On acid soils, a large rhizosheath increased shoot biomass compared with a small rhizosheath regardless of P supply. At low P supply, increased shoot biomass could be attributed to a greater uptake of soil P, but at high P supply the increased biomass was due to some other factor. Generation means analysis indicated that rhizosheath size on acid soil was controlled by multiple, additive loci. Subsequently, a quantitative trait loci (QTL) analysis of an F6 population of recombinant inbred lines identified five major loci contributing to the phenotype together accounting for over 60% of the total genetic variance. One locus on chromosome 1D accounted for 34% of the genotypic variation. Genetic control of rhizosheath size appears to be relatively simple and markers based on the QTL provide valuable tools for marker assisted breeding. PMID:26873980

  4. Red spruce germination and growth in soil-mediated regeneration microcosms under acid precipitation

    SciTech Connect

    Ho, M.

    1992-01-01

    In the past three decades, atmospheric pollution has caused substantial problems for the environment as well as for many biological processes. The objective of this study focuses on red spruce (Picea ruben Sarg.) regeneration potential and chemical change within the soil-water-plant continuum following simulated acid rain treatments. Inceptisols from three forests at 1735, 1920, and 2015 m at Mt. Mitchell, North Carolina had lower pH, bulk density, and higher organic matter, and base cations as altitude increased. Red spruce seeds were collected from two nearby standing trees at the 1735 m site. A strip-split-split plot experiment was constructed using soils from the two lower elevations, which support natural red spruce stands. Besides a control (pH 5.6, NO[sub 3]:SO[sub 4] ratio 0.10), eight treatments corresponding to two pHs (3.5 and 4.2) with four NO[sub 3]:SO[sub 4] ratios (0.20, 0.33, 0.40, and 0.67) each were used. Seedling emergence and growth, chemistry of soil. Soil leachate, and plant tissue were analyzed to test soil differences and treatment effects of acidity, nitrate, and sulfate. Temporal patterns of germination respond more to soil than to rain chemistry, but significant interactions were found. Besides higher survival, faster germinating seedlings in the 1735 m soil also produced more complex root system and more biomass. Lower root-to-shoot ratios at more acidic treatments suggest a negative effect of acidity on root growth. Canonical discriminant analysis revealed that factors controlling overall soil chemistry were dominated by soil origin, then by rain pH.

  5. Adsorption of antimony(V) by floodplain soils, amorphous iron(III) hydroxide and humic acid.

    PubMed

    Tighe, Matthew; Lockwood, Peter; Wilson, Susan

    2005-12-01

    Antimony (Sb) emissions to the environment are increasing, and there is a dearth of knowledge regarding Sb fate and behaviour in natural systems. In particular, there is a lack of understanding of sorption of the oxidised Sb(V) species onto soils and soil phases. In this study sorption of Sb(V) by two organic rich soils with high levels of oxalate extractable Fe was examined over the pH range of 2.5-7. Furthermore, the sorption behaviour of Sb(V) was examined in two phases mimicking those dominant in the experimental soils, namely a solid humic acid and an amorphous Fe(OH)3, across the same pH range. Sorption of Sb by the soils and the humic acid fitted a Freundlich type isotherm, with the equation parameters reflecting changes in bonding affinity corresponding to pH changes. The soils sorbed >75% of the added Sb in all trials, and 80-100% at pH values less than approximately 6.5. The Fe(OH)3 retained >95% of the added Sb in all experiments. The humic acid sorbed up to 60% of the added Sb at acidic pH values, but sorption decreased to zero at higher pH values. Further adsorption studies are recommended, such as examining the effects of ion competition and changes in ionic strength.

  6. Quality improvement of acidic soils by biochar derived from renewable materials.

    PubMed

    Moon, Deok Hyun; Hwang, Inseong; Chang, Yoon-Young; Koutsospyros, Agamemnon; Cheong, Kyung Hoon; Ji, Won Hyun; Park, Jeong-Hun

    2017-02-01

    Biochar derived from waste plant materials and agricultural residues was used to improve the quality of an acidic soil. The acidic soil was treated for 1 month with both soy bean stover-derived biochar and oak-derived biochar in the range of 1 to 5 wt% for pH improvement and exchangeable cation enhancement. Following 1 month of treatment, the soil pH was monitored and exchangeable cations were measured. Moreover, a maize growth experiment was performed for 14 days with selected treated soil samples to confirm the effectiveness of the treatment. The results showed that the pH of the treated acidic soil increased by more than 2 units, and the exchangeable cation values were greatly enhanced upon treatment with 5 wt% of both biochars, after 1 month of curing. Maize growth was superior in the 3 wt% biochar-treated samples compared to the control sample. The presented results demonstrate the effective use of biochar derived from renewable materials such as waste plant materials and agricultural residues for quality improvement of acidic soils.

  7. Paramagnetic properties of humus acids of podzolic and bog-podzolic soils

    NASA Astrophysics Data System (ADS)

    Lodygin, E. D.; Beznosikov, V. A.; Chukov, S. N.

    2007-07-01

    The contents of free radicals in preparations of humic and fulvic acids extracted from virgin and plowed podzolic, surface gleyic podzolic, and peaty podzolic-gleyic soils were determined. The concentration of paramagnetic centers in the humic acids was 1.5-2 times higher than that in the fulvic acids. The agricultural use decreases the paramagnetic activity of the humus compounds and promotes the accumulation of biothermodynamically stable organic compounds in the plow horizons.

  8. Nucleic Acid Extraction from Synthetic Mars Analog Soils for in situ Life Detection

    PubMed Central

    Mojarro, Angel; Ruvkun, Gary; Zuber, Maria T.

    2017-01-01

    Abstract Biological informational polymers such as nucleic acids have the potential to provide unambiguous evidence of life beyond Earth. To this end, we are developing an automated in situ life-detection instrument that integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG) instrument. Our goal is to isolate and determine the sequence of nucleic acids from extant or preserved life on Mars, if, for example, there is common ancestry to life on Mars and Earth. As is true of metagenomic analysis of terrestrial environmental samples, the SETG instrument must isolate nucleic acids from crude samples and then determine the DNA sequence of the unknown nucleic acids. Our initial DNA extraction experiments resulted in low to undetectable amounts of DNA due to soil chemistry–dependent soil-DNA interactions, namely adsorption to mineral surfaces, binding to divalent/trivalent cations, destruction by iron redox cycling, and acidic conditions. Subsequently, we developed soil-specific extraction protocols that increase DNA yields through a combination of desalting, utilization of competitive binders, and promotion of anaerobic conditions. Our results suggest that a combination of desalting and utilizing competitive binders may establish a “universal” nucleic acid extraction protocol suitable for analyzing samples from diverse soils on Mars. Key Words: Life-detection instruments—Nucleic acids—Mars—Panspermia. Astrobiology 17, 747–760. PMID:28704064

  9. A modified acid digestion procedure for extraction of tungsten from soil.

    PubMed

    Bednar, A J; Jones, W T; Chappell, M A; Johnson, D R; Ringelberg, D B

    2010-01-15

    Interest in tungsten occurrence and geochemistry is increasing due to increased use of tungsten compounds and its unknown biochemical effects. Tungsten has a complex geochemistry, existing in most environmental matrices as the soluble and mobile tungstate anion, as well as poly- and heteropolytungstates. Because the geochemistry of tungsten is substantially different than most trace metals, including the formation of insoluble species under acidic conditions, it is not extracted from soil matrices using standard acid digestion procedures. Therefore, the current work describes a modification to a commonly used acid digestion procedure to facilitate quantification of tungsten in soil matrices. Traditional soil digestion procedures, using nitric and hydrochloric acids with hydrogen peroxide yield <1 up to 50% recovery on soil matrix spike samples, whereas the modified method reported here, which includes the addition of phosphoric acid, yields spike recoveries in the 76-98% range. Comparison of the standard and modified digestion procedures on National Institute of Standards and Technology Standard Reference Materials yielded significantly improved tungsten recoveries for the phosphoric acid modified method. The modified method also produces comparable results for other acid extractable metals as the standard methods, and therefore can be used simultaneously for tungsten and other metals of interest.

  10. Nucleic Acid Extraction from Synthetic Mars Analog Soils for in situ Life Detection

    NASA Astrophysics Data System (ADS)

    Mojarro, Angel; Ruvkun, Gary; Zuber, Maria T.; Carr, Christopher E.

    2017-08-01

    Biological informational polymers such as nucleic acids have the potential to provide unambiguous evidence of life beyond Earth. To this end, we are developing an automated in situ life-detection instrument that integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG) instrument. Our goal is to isolate and determine the sequence of nucleic acids from extant or preserved life on Mars, if, for example, there is common ancestry to life on Mars and Earth. As is true of metagenomic analysis of terrestrial environmental samples, the SETG instrument must isolate nucleic acids from crude samples and then determine the DNA sequence of the unknown nucleic acids. Our initial DNA extraction experiments resulted in low to undetectable amounts of DNA due to soil chemistry-dependent soil-DNA interactions, namely adsorption to mineral surfaces, binding to divalent/trivalent cations, destruction by iron redox cycling, and acidic conditions. Subsequently, we developed soil-specific extraction protocols that increase DNA yields through a combination of desalting, utilization of competitive binders, and promotion of anaerobic conditions. Our results suggest that a combination of desalting and utilizing competitive binders may establish a "universal" nucleic acid extraction protocol suitable for analyzing samples from diverse soils on Mars.

  11. Citric acid facilitated thermal treatment: An innovative method for the remediation of mercury contaminated soil.

    PubMed

    Ma, Fujun; Peng, Changsheng; Hou, Deyi; Wu, Bin; Zhang, Qian; Li, Fasheng; Gu, Qingbao

    2015-12-30

    Thermal treatment is a promising technology for the remediation of mercury contaminated soils, but it often requires high energy input at heating temperatures above 600°C, and the treated soil is not suitable for agricultural reuse. The present study developed a novel method for the thermal treatment of mercury contaminated soils with the facilitation of citric acid (CA). A CA/Hg molar ratio of 15 was adopted as the optimum dosage. The mercury concentration in soils was successfully reduced from 134 mg/kg to 1.1mg/kg when treated at 400°C for 60 min and the treated soil retained most of its original soil physiochemical properties. During the treatment process, CA was found to provide an acidic environment which enhanced the volatilization of mercury. This method is expected to reduce energy input by 35% comparing to the traditional thermal treatment method, and lead to agricultural soil reuse, thus providing a greener and more sustainable remediation method for treating mercury contaminated soil in future engineering applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Chemical stabilization of cadmium in acidic soil using alkaline agronomic and industrial by-products.

    PubMed

    Chang, Yao-Tsung; Hsi, Hsing-Cheng; Hseu, Zeng-Yei; Jheng, Shao-Liang

    2013-01-01

    In situ immobilization of heavy metals using reactive or stabilizing materials is a promising solution for soil remediation. Therefore, four agronomic and industrial by-products [wood biochar (WB), crushed oyster shell (OS), blast furnace slag (BFS), and fluidized-bed crystallized calcium (FBCC)] and CaCO3 were added to acidic soil (Cd = 8.71 mg kg(-1)) at the rates of 1%, 2%, and 4% and incubated for 90 d. Chinese cabbage (Brassica chinensis L.) was then planted in the soil to test the Cd uptake. The elevation in soil pH caused by adding the by-products produced a negative charge on the soil surface, which enhanced Cd adsorption. Consequently, the diethylenetriamine pentaacetic acid (DTPA)-extractable Cd content decreased significantly (P < 0.05) in the incubated soil. These results from the sequential extraction procedure indicated that Cd converted from the exchangeable fraction to the carbonate or Fe-Mn oxide fraction. The long-term effectiveness of Cd immobilization caused by applying the 4 by-products was much greater than that caused by applying CaCO3. Plant shoot biomass clearly increased because of the by-product soil amendment. Cd concentration in the shoots was < 10.0 mg kg(-1) following by-product application, as compared to 24 mg kg(-1) for plants growing in unamended soil.

  13. Influence of soil tillage and erosion on the dispersion of glyphosate and aminomethylphosphonic acid in agricultural soils

    NASA Astrophysics Data System (ADS)

    Todorovic, Gorana Rampazzo; Rampazzo, Nicola; Mentler, Axel; Blum, Winfried E. H.; Eder, Alexander; Strauss, Peter

    2014-03-01

    Erosion processes can strongly influence the dissipation of glyphosate and aminomethylphosphonic acid applied with Roundup Max® in agricultural soils; in addition, the soil structure state shortly before erosive precipitations fall can be a key parameter for the distribution of glyphosate and its metabolite. Field rain simulation experiments showed that severe erosion processes immediately after application of Roundup Max® can lead to serious unexpected glyphosate loss even in soils with a high presumed adsorption like the Cambisols, if their structure is unfavourable. In one of the no-tillage-plot of the Cambisol, up to 47% of the applied glyphosate amount was dissipated with surface run-off. Moreover, at the Chernozem site with high erosion risk and lower adsorption potential, glyphosate could be found in collected percolation water transported far outside the 2x2 m experimental plots. Traces of glyphosate were found also outside the treated agricultural fields.

  14. Effective treatment of PAH contaminated Superfund site soil with the peroxy-acid process.

    PubMed

    Scott Alderman, N; N'Guessan, Adeola L; Nyman, Marianne C

    2007-07-31

    Peroxy-organic acids are formed by the chemical reaction between organic acids and hydrogen peroxide. The peroxy-acid process was applied to two Superfund site soils provided by the U.S. Environmental Protection Agency (EPA). Initial small-scale experiments applied ratios of 3:5:7 (v/v/v) or 3:3:9 (v/v/v) hydrogen peroxide:acetic acid:deionized (DI) water solution to 5g of Superfund site soil. The experiment using 3:5:7 (v/v/v) ratio resulted in an almost complete degradation of the 14 EPA regulated polycyclic aromatic hydrocarbons (PAHs) in Bedford LT soil during a 24-h reaction period, while the 3:3:9 (v/v/v) ratio resulted in no applicable degradation in Bedford LT lot 10 soil over the same reaction period. Specific Superfund site soil characteristics (e.g., pH, total organic carbon content and particle size distribution) were found to play an important role in the availability of the PAHs and the efficiency of the transformation during the peroxy-acid process. A scaled-up experiment followed treating 150g of Bedford LT lot 10 soil with and without mixing. The scaled-up processes applied a 3:3:9 (v/v/v) solution resulting in significant decrease in PAH contamination. These findings demonstrate the peroxy-acid process as a viable option for the treatment of PAH contaminated soils. Further work is necessary in order to elucidate the mechanisms of this process.

  15. Effect of pH and organic acids on nitrogen transformations and metal dissolution in soils

    SciTech Connect

    Fu, Minhong.

    1989-01-01

    The effect of pH (4, 6, and 8) on nitrogen mineralization was evaluated in three Iowa surface soils treated with crop residues (corn (Zea mays L.), soybean (Glycine max (L.) Merr.), and sorghum (Sorghum vulgare Pers.), or alfalfa (Medicago sativa L.)) and incubated in leaching columns under aerobic conditions at 30C for 20 weeks. In general, N mineralization was significantly depressed at soil pH 4, compared with pH 6 or 8. The types of crop residues added influenced the pattern and amount of N mineralization. A study on the effect of 19 trace elements on the nitrate red activity of four Iowa surface soils showed that most trace elements inhibited this enzyme in acid and neutral soils. The trace elements Ag(I), Cd(II), Se(IV), As(V), and W(VI) were the most effective inhibitors, with >75% inhibition. Mn(II) was the least effective inhibitor, with <10% inhibition. Other trace elements included Cu(I), Co(II), Cu(II), Fe(II), Ni(II), Pb(II), Zn(II), Al(III), As(III), Cr(III), Fe(III), V(IV), Mo(VI), and Se(VI). The application of high-performance liquid chromatography (HPLC) showed that, when coupled to a refractive index detector, it is a rapid, sensitive, and accurate method for determining organic acids in soils. Three organic acids, acetic (2-20 mM), propionic (0-3 mM), and n-butyric (0-1.4 mM), were identified with HPLC and confirmed by gas chromatography in crop-residue-treated soils incubated under waterlogged conditions at 25C for 72 h. No organic acids were detected under aerobic conditions. Four mineral acids and 29 organic acids were studied for their effect on N mineralization and metal dissolution in soils incubated under waterlogged conditions at 30C for 10 days.

  16. Emission control for precursors causing acid rain (V): Improvement of acid soil with the bio-briquette combustion ash.

    PubMed

    Dong, Xu-Hui; Sakamoto, Kazuhiko; Wang, Wei; Gao, Shi-Dong; Isobe, Yugo

    2004-01-01

    The bio-briquette technique which mixes coal, biomass and sulfur fixation agent and bio-briquettes under 3-5 t/cm2 line pressure has aroused people's attention in view of controlling the air pollution and the acid rain. In this paper, the physicochemical properties of bio-briquette and its ash were investigated. And the acid soil was improved by the bio-briquette combustion ash, which contained nutritive substances such as P, N, K and had the acid-neutralizing capacity (ANC). The pH, EC, effective nutrient elements (Ca, Mg, K, P and N), heavy metal elements (Al, Cu, Cd, Cr, Zn and Mn) and acid-neutralizing capacity change of ash-added soils within the range of 0-10%, were also studied. Specially, when 5% bio-briquette combustion ash was added to the tested soil, the content of the effective elements such as Ca, Mg and K rose by 100 times, 7 times and twice, respectively. The total nitrogen also increased by about twice. The results showed the oxyanions such as that of Al, Cu, Cd, Cr, Zn and Mn were not potentially dangerous, because they were about the same as the averages of them in Chinese soil. It is shown that the ANC became stronger, though the ANC hardly increases in the ash-added soil. On the basis of the evaluation indices, it is concluded that the best mixture ratio is to add 2.5%-8% of the bio-briquette combustion ash to the tested soil.

  17. Soil solution response to experimentally reduced acid deposition in a forest ecosystem

    SciTech Connect

    Alewell, C.; Matzner, E.; Bredemeier, M.; Blanch, K.

    1997-05-01

    In order to measure and predict reversibility of soil solution acidification under experimentally reduced acid input, a manipulation study with artificial {open_quote}preindustrial{close_quote} throughfall was established. A roof was installed underneath the canopy in a Norway Spruce stand of the German Soiling area. Water failing onto the roof was adjusted to clean rain concentrations before redistribution. Soil solutions were collected with suction cup lysimeters at various depths and were analyzed for major ions. The response of soil solution chemistry in the upper soil (10 cm depth) to a reduction of N, SO{sub 4}, and H input was rapid. While NO{sub 3} concentration in deeper soil layers reached input levels after 2 yr of treatment, SO{sub 4} concentration in the seepage water at 1 m depth remained high relative to the reduced input due to a release of formerly stored S from the soil. Aluminum concentration followed a similar pattern as the SO{sub 4} concentrations. The ion concentrations in soil leachate were predicted reasonably well using the MAGIC model with the measured SO{sub 4} sorption isotherms and the throughfall fluxes as model input Although the parameters of the Langmuir isotherm had no significant influence to the prediction of SO{sub 4} concentration in the upper soil layer, they were crucial for the prediction of SO{sub 4} dynamics in deeper soil layers. The model predicted that the reversibility of soil acidification at the Soiling area is delayed for decades due to the release of soil SO{sub 4}. 38 refs., 5 figs., 4 tabs.

  18. The role of arbuscular mycorrhizas in decreasing aluminium phytotoxicity in acidic soils: a review.

    PubMed

    Seguel, Alex; Cumming, Jonathan R; Klugh-Stewart, Katrina; Cornejo, Pablo; Borie, Fernando

    2013-04-01

    Soil acidity is an impediment to agricultural production on a significant portion of arable land worldwide. Low productivity of these soils is mainly due to nutrient limitation and the presence of high levels of aluminium (Al), which causes deleterious effects on plant physiology and growth. In response to acidic soil stress, plants have evolved various mechanisms to tolerate high concentrations of Al in the soil solution. These strategies for Al detoxification include mechanisms that reduce the activity of Al3+ and its toxicity, either externally through exudation of Al-chelating compounds such as organic acids into the rhizosphere or internally through the accumulation of Al-organic acid complexes sequestered within plant cells. Additionally, root colonization by symbiotic arbuscular mycorrhizal (AM) fungi increases plant resistance to acidity and phytotoxic levels of Al in the soil environment. In this review, the role of the AM symbiosis in increasing the Al resistance of plants in natural and agricultural ecosystems under phytotoxic conditions of Al is discussed. Mechanisms of Al resistance induced by AM fungi in host plants and variation in resistance among AM fungi that contribute to detoxifying Al in the rhizosphere environment are considered with respect to altering Al bioavailability.

  19. Lanthanides in humic acids of soils, paleosols and cultural horizons (Southern Urals, Russia)

    NASA Astrophysics Data System (ADS)

    Dergacheva, Maria; Nekrasova, Olga

    2013-04-01

    In recent years, commercial interest in this element group increases. As consequence, their content may increase in environment, including soil and soil components. This requires quantitative estimations of rare metal accumulation by soils and their humic acids. The latter began to be actively used as fertilizers and it is alarming, because information about rare element participation (including lanthanides) in metabolism of live organisms is inconsistent. There was investigated lanthanide content in humic acids extracted from humus horizons of different objects of archaeological site Steppe 7 (Southern Urals, Russia). Humic acids were extracted from modern background soils and paleosols and cultural horizons of the Bronze Age as well. According to archaeological data burial of paleosols under a barrow and formation of the cultural layer (CL) took place 3600 and 3300-3200 years BP, respectively. The area of the site is located in the forest-steppe landscape, far from industrial plants. Lanthanides in soils are immobile elements, and such number of objects will allow to receive information about their content changing over time and to have more detailed basis for the future monitoring of this territory as well. Humic acids were precipitated from 0,1 n NaOH extraction after preliminary decalcification. Cleaning of humic acid preparations by 6N HCl or HF+HCl was not carried out. Determination of La, Ce, Sm, Eu, Tb, Yb and Lu was performed by multi-element neutron-activation analysis. According to carried out diagnostics and reconstruction of natural conditions of all object formation, all objects correspond to steppe type landscape with a different level of humidity. Analysis of received data has shown that cerium is presented in humic acid preparations in the largest quantities among lanthanides (on average 4,0-6,6 mg/kg of preparation mass). The average content of samarium, europium, ytterbium and lutetium in the humic acids in the order of magnitude ranges from 0

  20. Impacts of simulated acid rain on recalcitrance of two different soils.

    PubMed

    Dai, Zhongmin; Liu, Xingmei; Wu, Jianjun; Xu, Jianming

    2013-06-01

    Laboratory experiments were conducted to estimate the impacts of simulated acid rain (SAR) on recalcitrance in a Plinthudult and a Paleudalfs soil in south China, which were a variable and a permanent charge soil, respectively. Simulated acid rains were prepared at pH 2.0, 3.5, 5.0, and 6.0, by additions of different volumes of H2SO4 plus HNO3 at a ratio of 6 to 1. The leaching period was designed to represent 5 years of local annual rainfall (1,200 mm) with a 33 % surface runoff loss. Both soils underwent both acidification stages of (1) cation exchange and (2) mineral weathering at SAR pH 2.0, whereas only cation exchange occurred above SAR pH 3.5, i.e., weathering did not commence. The cation exchange stage was more easily changed into that of mineral weathering in the Plinthudult than in the Paleudalfs soil, and there were some K(+) and Mg(2+) ions released on the stages of mineral weathering in the Paleudalfs soil. During the leaching, the release of exchangeable base cations followed the order Ca(2+) >K(+) >Mg(2+) >Na(+) for the Plinthudult and Ca(2+) >Mg(2+) >Na(+) >K(+) for the Paleudalfs soil. The SARs above pH 3.5 did not decrease soil pH or pH buffering capacity, while the SAR at pH 2.0 decreased soil pH and the buffering capacity significantly. We conclude that acid rain, which always has a pH from 3.5 to 5.6, only makes a small contribution to the acidification of agricultural soils of south China in the short term of 5 years. Also, Paleudalfs soils are more resistant to acid rain than Plinthudult soils. The different abilities to prevent leaching by acid rain depend upon the parent materials, types of clay minerals, and soil development degrees.

  1. N{sub 2}O production pathways in the subtropical acid forest soils in China

    SciTech Connect

    Zhang Jinbo; Cai Zucong; Zhu Tongbin

    2011-07-15

    To date, N{sub 2}O production pathways are poorly understood in the humid subtropical and tropical forest soils. A {sup 15}N-tracing experiment was carried out under controlled laboratory conditions to investigate the processes responsible for N{sub 2}O production in four subtropical acid forest soils (pH<4.5) in China. The results showed that denitrification was the main source of N{sub 2}O emission in the subtropical acid forest soils, being responsible for 56.1%, 53.5%, 54.4%, and 55.2% of N{sub 2}O production, in the GC, GS, GB, and TC soils, respectively, under aerobic conditions (40%-52%WFPS). The heterotrophic nitrification (recalcitrant organic N oxidation) accounted for 27.3%-41.8% of N{sub 2}O production, while the contribution of autotrophic nitrification was little in the studied subtropical acid forest soils. The ratios of N{sub 2}O-N emission from total nitrification (heterotrophic+autotrophic nitrification) were higher than those in most previous references. The soil with the lowest pH and highest organic-C content (GB) had the highest ratio (1.63%), suggesting that soil pH-organic matter interactions may exist and affect N{sub 2}O product ratios from nitrification. The ratio of N{sub 2}O-N emission from heterotrophic nitrification varied from 0.02% to 25.4% due to soil pH and organic matter. Results are valuable in the accurate modeling of N2O production in the subtropical acid forest soils and global budget. - Highlights: {yields} We studied N{sub 2}O production pathways in subtropical acid forest soil under aerobic conditions. {yields} Denitrification was the main source of N{sub 2}O production in subtropical acid forest soils. {yields} Heterotrophic nitrification accounted for 27.3%-41.8% of N{sub 2}O production. {yields} While, contribution of autotrophic nitrification to N{sub 2}O production was little. {yields} Ratios of N{sub 2}O-N emission from nitrification were higher than those in most previous references.

  2. Extractability of elements in sugar maple xylem along a gradient of soil acidity.

    PubMed

    Bilodeau Gauthier, Simon; Houle, Daniel; Gagnon, Christian; Côté, Benoît; Messier, Christian

    2008-01-01

    Dendrochemistry has been used for the historical dating of pollution. Its reliability is questionable due primarily to the radial mobility of elements in sapwood. In the present study, the extractability of seven elements was characterized to assess their suitability for the monitoring of environmental conditions. Nine mature sugar maple trees (Acer saccharum Marsh.), a wide-ranging species in eastern North America that has suffered decline in past decades, were sampled in three Quebec watersheds along a soil acidity gradient. Five-year groups of annual tree rings were treated by sequential chemical extractions using extractants of varying strength (deionized H2O, 0.05 M HCl, and concentrated HNO(3)) to selectively solubilize the elements into three fractions (water-soluble, acid-soluble, and residual). Monovalent K; divalent Ba, Ca, Cd, Mg, Mn; and trivalent Al cations were found mostly in the water-soluble, acid-soluble, and residual fractions, respectively. Forms more likely to be mobile within the tree (water-soluble and acid-soluble) do not seem to be suitable for temporal monitoring because of potential lateral redistribution in sapwood rings. However, certain elements (Cd, Mn) were responsive to current soil acidity and could be used in spatial variation monitoring. Extractability of Al varied according to soil acidity; at less acidic sites, up to 90% of Al was contained in the residual form, whereas on very acidic soils, as much as 45% was found in the water-soluble and acid-soluble fractions. Sequential extractions can be useful for determining specific forms of metals as key indicators of soil acidification.

  3. Using spin labels to study molecular processes in soils: Covalent binding of aromatic amines to humic acids of soils

    NASA Astrophysics Data System (ADS)

    Aleksandrova, O. N.; Kholodov, V. A.; Perminova, I. V.

    2015-08-01

    Interactions of aliphatic and aromatic amines with soil and humic acids isolated from it are studied by means of spin labels and electron paramagnetic resonance (EPR) spectroscopy. Nitroxyl radicals containing amino groups are used as spin labels. It is found experimentally that aromatic amines are instantaneously converted to the bound state. It is shown