29 results on '"Yongming Luo"'
Search Results
2. Legacy of contamination with metal(loid)s and their potential mobilization in soils at a carbonate-hosted lead-zinc mine area
- Author
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Xinyang Li, Tong Zhou, Zhu Li, Wenyong Wang, Jiawen Zhou, Pengjie Hu, Yongming Luo, Peter Christie, and Longhua Wu
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Silicon ,Environmental Engineering ,Sulfates ,Health, Toxicology and Mutagenesis ,Iron ,Public Health, Environmental and Occupational Health ,Carbonates ,Water ,General Medicine ,General Chemistry ,Pollution ,Soil ,Zinc ,Lead ,Metals, Heavy ,Environmental Chemistry ,Soil Pollutants ,Calcium ,Cadmium ,Environmental Monitoring - Abstract
Chemical weathering of carbonate-hosted Pb-Zn mines via acid-promoted or oxidative dissolution generates metal-bearing colloids at neutral mine drainage sites. However, the mobility and bioavailability of the colloids associated with metals in nearby soils are unknown. Here, we monitored the mobility of metal(loid)s in soils affected by aeolian deposition and river transport in the vicinity of a carbonate-hosted Pb-Zn mine. Using chemical extraction, ultrafiltration, and microscopic and spectroscopic analysis of metals we find that contamination levels of the soil metals cadmium (Cd), lead (Pb) and zinc (Zn) were negatively correlated with metal extractability. However, nano-scale characterization indicates that colloid-metal(loid) interactions induced potential mobilization and increased risk from metal(loid)s. Dynamic light scattering (DLS) and HRTEM-EDX-SAED analysis further indicate that organic matter (OM)-rich nano-colloids associated with calcium (Ca), silicon (Si) and iron (Fe) precipitates accounted for the majority of the dissolved metal fractions in carbonate-hosted Pb-Zn mine soils. More stable nano-crystals (ZnS, ZnCO
- Published
- 2022
3. Synergistic improving photo-Fenton and photo-catalytic degradation of carbamazepine over FeS
- Author
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Chao, Gong, Jinli, Zhai, Xi, Wang, Wenjie, Zhu, Daoli, Yang, Yongming, Luo, and Xiaoya, Gao
- Subjects
Minerals ,Carbamazepine ,Iron ,Environmental Pollutants ,Oxides ,Ascorbic Acid ,Hydrogen Peroxide ,Citric Acid - Abstract
Herein, a heterogeneous photo-Fenton and photo-catalytic system was constructed using oxide pyrite (FeS
- Published
- 2022
4. Investigation of defect-rich CeO
- Author
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Ying, Zhang, Liming, Zhang, Jichang, Lu, Wei, Liao, Jin, Zhang, Xiaoya, Gao, Yongming, Luo, and Wenjie, Zhu
- Abstract
Spherical cerium dioxide (CeO
- Published
- 2022
5. Synergistic improving photo-Fenton and photo-catalytic degradation of carbamazepine over FeS2/Fe2O3/organic acid with H2O2 in-situ generation
- Author
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Chao Gong, Jinli Zhai, Xi Wang, Wenjie Zhu, Daoli Yang, Yongming Luo, and Xiaoya Gao
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Environmental Engineering ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Environmental Chemistry ,General Medicine ,General Chemistry ,Pollution - Published
- 2022
6. Investigation of defect-rich CeO2 catalysts for super low-temperature catalytic oxidation and durable styrene removal
- Author
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Ying Zhang, Liming Zhang, Jichang Lu, Wei Liao, Jin Zhang, Xiaoya Gao, Yongming Luo, and Wenjie Zhu
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Environmental Engineering ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Environmental Chemistry ,General Medicine ,General Chemistry ,Pollution - Published
- 2022
7. Hydrogen peroxide combined with surfactant leaching and microbial community recovery from oil sludge
- Author
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Weiyan Chen, Yongming Luo, Qingling Wang, Ding Zhixian, Peter Christie, Jinyu Hou, and Wuxing Liu
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Environmental Engineering ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Surface-Active Agents ,chemistry.chemical_compound ,Pulmonary surfactant ,Soil Pollutants ,Environmental Chemistry ,Hydrogen peroxide ,Soil Microbiology ,Sewage ,Microbiota ,Public Health, Environmental and Occupational Health ,Hydrogen Peroxide ,General Medicine ,General Chemistry ,Pollution ,Hydrocarbons ,Biodegradation, Environmental ,Petroleum ,chemistry ,Microbial population biology ,Environmental chemistry ,Leaching (metallurgy) ,Oil sludge - Abstract
The remediation effects of hydrogen peroxide (H2O2) oxidation and surfactant-leaching alone or in combination on three typical oilfield sludges were studied. The removal efficiency of total petroleum hydrocarbons (TPHs) of Jidong, Liaohe and Jiangsu oil sludges by hydrogen peroxide oxidation alone was very poor (6.5, 6.8, and 3.4 %, respectively) but increased significantly (p
- Published
- 2022
8. Pollution, ecological-health risks, and sources of heavy metals in soil of the northeastern Qinghai-Tibet Plateau
- Author
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Xiuyun Min, Jian Lu, Yongming Luo, Jun Wu, and Leiming Li
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Adult ,Pollution ,China ,Environmental Engineering ,Ecological health ,Soil test ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,Tibet ,Risk Assessment ,01 natural sciences ,Soil ,Environmental protection ,Metals, Heavy ,Humans ,Industry ,Soil Pollutants ,Environmental Chemistry ,Child ,Ecosystem ,0105 earth and related environmental sciences ,media_common ,Pollutant ,021110 strategic, defence & security studies ,geography ,Plateau ,geography.geographical_feature_category ,Public Health, Environmental and Occupational Health ,Heavy metals ,General Medicine ,General Chemistry ,Contamination ,Environmental science ,Environmental Pollution ,Enrichment factor ,Environmental Monitoring - Abstract
The Qinghai-Tibet Plateau, especially the northeastern region, is not a pure land any more due to recently increasing anthropogenic activities. This study collected soil samples from 70 sites of the northeastern Qinghai-Tibet Plateau to evaluate pollution, ecological-health risks, and possible pollution sources of heavy metals. The concentrations of heavy metals in soil were relatively high. Values of geo-accumulation index exhibited that Hg pollution was the most serious meanwhile Hg possessed the strongest enrichment feature based on enrichment factor values. The modified degrees of contamination showed that about 54.3% and 17.1% of sampling sites were at moderate and high contamination degree while pollution load indexes illustrated that 72.9% and 27.1% of sampling sites possessed moderate and high contamination level, respectively. Ecological risk indexes of heavy metals in soil ranged from 234.6 to 3759.0, suggesting that most of sites were under considerable/very high risks. Cancer risks for adults and children were determined as high and high-very high levels while non-cancer risks for children were high although those for adults were low. Industrial source contributed to the main fraction of ecological and health risks. Summarily speaking, heavy metals in soil of the study area has caused significantly serious pollution and exerted high potential ecological and health risks, especially for children who are more susceptible to hurt from pollutants. Therefore, more efficient and strict pollution control and management in study area should be put out as soon as possible.
- Published
- 2018
9. Biosurfactant-producing microorganism Pseudomonas sp. SB assists the phytoremediation of DDT-contaminated soil by two grass species
- Author
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Wuxing Liu, Beibei Wang, Ying Teng, Qingling Wang, Jinyu Hou, Xiaoyan Liu, Yongming Luo, and Peter Christie
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Festuca ,Environmental Engineering ,Environmental remediation ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,engineering.material ,Poaceae ,01 natural sciences ,DDT ,Bioremediation ,Pseudomonas ,Botany ,Lolium ,Soil Pollutants ,Environmental Chemistry ,Microbial biodegradation ,Fertilizers ,Soil Microbiology ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Rhizosphere ,biology ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,biology.organism_classification ,Pollution ,Soil contamination ,Acidobacteria ,Phytoremediation ,Biodegradation, Environmental ,Agronomy ,engineering ,Fertilizer - Abstract
Phytoremediation together with microorganisms may confer the advantages of both phytoremediation and microbial remediation of soils containing organic contaminants. In this system biosurfactants produced by Pseudomonas sp. SB may effectively help to increase the bioavailability of organic pollutants and thereby enhance their microbial degradation in soil. Plants may enhance the rhizosphere environment for microorganisms and thus promote the bioremediation of contaminants. In the present pot experiment study, dichlorodiphenyltrichloroethane (DDT) residues underwent an apparent decline after soil bioremediation compared with the original soil. The removal efficiency of fertilizer + tall fescue, fertilizer + tall fescue + Pseudomonas, fertilizer + perennial ryegrass, and fertilizer + perennial ryegrass + Pseudomonas treatments were 59.4, 65.6, 69.0, and 65.9%, respectively, and were generally higher than that in the fertilizer control (40.3%). Principal coordinates analysis (PCoA) verifies that plant species greatly affected the soil bacterial community irrespective of inoculation with Pseudomonas sp. SB. Furthermore, community composition analysis shows that Proteobacteria, Acidobacteria and Actinobacteria were the three dominant phyla in all groups. In particular, the relative abundance of Pseudomonas for fertilizer + tall fescue + Pseudomonas (0.25%) was significantly greater than fertilizer + tall fescue and this was related to the DDT removal efficiency.
- Published
- 2017
10. Evaluation of fatty acid derivatives in the remediation of aged PAH-contaminated soil and microbial community and degradation gene response
- Author
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Wuxing Liu, Yongming Luo, Qingling Wang, Jinyu Hou, Yucheng Wu, Jing Yuan, and Peter Christie
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Environmental Engineering ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Sodium ,0208 environmental biotechnology ,chemistry.chemical_element ,02 engineering and technology ,Lysobacter ,010501 environmental sciences ,complex mixtures ,01 natural sciences ,Plant Roots ,Actinobacteria ,Soil ,Pseudoxanthomonas ,Environmental Chemistry ,Soil Pollutants ,Polycyclic Aromatic Hydrocarbons ,Environmental Restoration and Remediation ,Soil Microbiology ,0105 earth and related environmental sciences ,biology ,Bacteria ,Microbiota ,Pseudomonas ,Fatty Acids ,Public Health, Environmental and Occupational Health ,food and beverages ,General Medicine ,General Chemistry ,biology.organism_classification ,Pollution ,Soil contamination ,020801 environmental engineering ,Biodegradation, Environmental ,chemistry ,Environmental chemistry ,bacteria ,Rhodococcus ,Gammaproteobacteria - Abstract
In this study, derivatives of two common fatty acids in plant root exudates, sodium palmitate and sodium linoleate (sodium aliphatates), were added to an aged Polycyclic aromatic hydrocarbons (PAHs) contaminated soil to estimate their effectiveness in the removal of PAHs. Sodium linoleate was more effective in lowering PAHs and especially high-molecular-weight (4-6 ring) PAHs (HMW-PAHs). Principal coordinates analysis (PCoA) indicates that both amendments led to a shift in the soil bacterial community. Moreover, linear discriminant effect size (LEfSe) analysis demonstrates that the specific PAHs degraders Pseudomonas, Arenimonas, Pseudoxanthomonas and Lysobacter belonging to the ฮณ-proteobacteria and Nocardia and Rhodococcus belonging to the Actinobacteria were the biomarkers of, respectively, sodium linoleate and sodium palmitate amendments. Correlation analysis suggests that four biomarkers in the sodium linoleate amendment treatment from ฮณ-proteobacteria were all highly linearly negatively related to HMW-PAHs residues (p 0.01) while two biomarkers in the sodium palmitate amendment treatment from Actinobacteria were highly linearly negatively related to LMW-PAHs residues (p 0.01). Higher removal efficiency of PAHs (especially HMW-PAHs) in the sodium linoleate amendment treatment than in the sodium palmitate amendment treatment might be ascribed to the specific enrichment of microbes from the ฮณ-proteobacteria. The bacterial functional KEGG orthologs (KOs) assigned to PAHs metabolism and functional C23O and C12O genes related to cleavage of the benzene ring were both up-regulated. These results provide new insight into the mechanisms of the two sodium aliphatate amendments in accelerating PAHs biodegradation and have implications for practical application in the remediation of PAHs-contaminated soils.
- Published
- 2019
11. Residues and risks of veterinary antibiotics in protected vegetable soils following application of different manures
- Author
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Yongming Luo, Liu Xinghua, Yujuan Huang, Yang Zhou, Longhua Wu, and Haibo Zhang
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Risk ,China ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,02 engineering and technology ,Oxytetracycline ,010501 environmental sciences ,engineering.material ,01 natural sciences ,Soil ,Vegetables ,medicine ,Soil Pollutants ,Environmental Chemistry ,Fertilizers ,0105 earth and related environmental sciences ,Organic Agriculture ,021110 strategic, defence & security studies ,Compost ,Public Health, Environmental and Occupational Health ,Veterinary Drugs ,General Medicine ,General Chemistry ,Pollution ,Soil contamination ,Manure ,Anti-Bacterial Agents ,Agronomy ,Soil water ,Organic farming ,engineering ,Environmental science ,Fertilizer ,Soil fertility ,Environmental Monitoring ,medicine.drug - Abstract
The protected vegetable farming is a style of high frequent rotation farming which requires a huge amount of fertilizers to maintain soil fertility. A total of 125 surface soils covering from east to west of China were sampled for the analysis of 17 antibiotics in order to identify antibiotics contamination caused by long-term manures application. The results indicate that the agricultural land has accumulated a statistically significantly higher antibiotics concentration than conventional open croplands. The maximum oxytetracycline concentration was 8400 ฮผg kg(-1), the highest level that has ever been reported for oxytetracycline in soils. The residual concentration is decided by both plant duration and manure type. Short-term (
- Published
- 2016
12. Effects of plastic film residues on occurrence of phthalates and microbial activity in soils
- Author
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Shenghong Lv, Manyun Zhang, Shen Zhang, Yongming Luo, Gangcai Chen, Ying Teng, Tongbin Zhu, Jun Wang, and Peter Christie
- Subjects
animal structures ,Environmental Engineering ,Nitrogen ,Health, Toxicology and Mutagenesis ,Phthalic Acids ,Plastic film ,chemistry.chemical_element ,010501 environmental sciences ,01 natural sciences ,Soil ,chemistry.chemical_compound ,Soil Pollutants ,Environmental Chemistry ,Food science ,Soil Microbiology ,0105 earth and related environmental sciences ,Public Health, Environmental and Occupational Health ,Agriculture ,04 agricultural and veterinary sciences ,General Medicine ,General Chemistry ,Chinese agriculture ,Pollution ,Carbon ,Phthalic acid ,Agronomy ,chemistry ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Plastics ,Soil microbiology ,Mulch - Abstract
Plastic film mulching has played an important role in Chinese agriculture, especially in vegetable production, but large amounts of film residues can accumulate in the soil. The present study investigated the effects of plastic film residues on the occurrence of soil PAEs and microbial activities using a batch pot experiment. PAE concentrations increased with increasing plastic film residues but the soil microbial carbon and nitrogen, enzyme activities and microbial diversity decreased significantly. At the end of the experiment the PAE concentrations were 0-2.02 mg kg(-1) in the different treatments. Soil microbial C and N, enzyme activities, AWCD value, and Shannon-Weaver and Simpson indices declined by about 28.9-76.2%, 14.9-59.0%, 4.9-22.7%, 23.0-42.0% and 1.8-18.7%, respectively. Soil microbial activity was positively correlated with soil PAE concentration, and soil PAE concentrations were impacted by plastic color and residue volume. Correlations among, and molecular mechanisms of, plastic film residues, PAE occurrence and microbial activity require further study.
- Published
- 2016
13. The limited facilitating effect of dissolved organic matter extracted from organic wastes on the transport of titanium dioxide nanoparticles in acidic saturated porous media
- Author
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Chen Tu, Yongming Luo, Ruichang Zhang, and Haibo Zhang
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Environmental Engineering ,Swine ,Health, Toxicology and Mutagenesis ,0208 environmental biotechnology ,Nanoparticle ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Nanomaterials ,chemistry.chemical_compound ,Dissolved organic carbon ,Animals ,Environmental Chemistry ,Humic acid ,Benzopyrans ,Organic matter ,Humic Substances ,0105 earth and related environmental sciences ,Titanium ,chemistry.chemical_classification ,Sewage ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Pollution ,Manure ,020801 environmental engineering ,chemistry ,Environmental chemistry ,Titanium dioxide ,Nanoparticles ,Porous medium ,Porosity - Abstract
The complexity of natural dissolved organic matter (DOM) motivates the determination of how DOM from diverse sources affects the environmental behaviors of engineered nanoparticles. Here, three types of DOM, DOM extracted from swine manure (SWDOM), sludge (SLDOM) and sediment (SEDOM), were characterized, and their effects on the transport of titanium dioxide nanoparticles (TiO2 NPs, 30 nm in diameter) were evaluated and compared with those of humic acid (HA). Characterization tests showed differences in the aromaticity and weight-average molecular weight (Mw) properties among the three extracted DOM solutions, and greater distinctions were found between the extracted DOM and HA. All the extracted DOM facilitated TiO2 NPs transport in acidic porous media. Nevertheless, the enhancing effects varied among the different extracted DOM types. SWDOM had a promoting effect on TiO2 NPs mobility that was equivalent to that of SEDOM and much higher than that of SLDOM. However, the facilitating effects of all three extracted DOM types were limited compared to that of HA. Based on the combined analysis of DOM properties and TiO2 NPs transport behaviors, it could be concluded that aromaticity and Mw were the key properties determining the limited promoting effects of DOM on TiO2 NPs mobility, and the specific UV absorbance at 280 nm (normalized by concentration, SUVA280) was a facile and useful indicator of the DOM-promoted transport of TiO2 NPs. These findings revealed that transport potential in the presence of DOM would be overestimated if either HA or fulvic acid were chosen as the DOM model in studies.
- Published
- 2019
14. Changes in metal mobility assessed by EDTA kinetic extraction in three polluted soils after repeated phytoremediation using a cadmium/zinc hyperaccumulator
- Author
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Zhu Li, Peter Christie, Yongming Luo, and Longhua Wu
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Environmental Engineering ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,010501 environmental sciences ,01 natural sciences ,Sedum ,Metal ,Soil ,Environmental Chemistry ,Soil Pollutants ,Hyperaccumulator ,Edetic Acid ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Cadmium ,Chemistry ,Extraction (chemistry) ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Human decontamination ,Pollution ,Phytoremediation ,Kinetics ,Biodegradation, Environmental ,Lead ,visual_art ,Environmental chemistry ,Soil water ,visual_art.visual_art_medium ,Copper - Abstract
Phytoextraction is one of the most promising technologies for the decontamination of metal-polluted agricultural soils. Effects of repeated phytoextraction by the cadmium (Cd)/zinc (Zn) hyperaccumulator Sedum plumbizincicola on metal (Cd, Zn, copper (Cu) and lead (Pb)) mobility were investigated in three contaminated soils with contrasting properties. EDTA kinetic extraction and the two first-order reactions model showed advantages in the assessment of soil metal mobility and clearly discriminated changes in metal fractions induced by phytoextraction. Repeated phytoextraction led to large decreases in readily labile (Q10) and less labile (Q20) fractions of Cd and Zn in all three soils with the sole exception of an increase in the Q20 of Zn in the highly polluted soil. However, Q10 fractions of soil Cu and Pb showed apparent increases with the sole exception of Pb in the acid polluted soil but showed a higher desorption rate constant (k1). Furthermore, S. plumbizincicola decreased the non-labile fraction (Q30) of all metals tested, indicating that the hyperaccumulator can redistribute soil metals from non-labile to labile fractions. This suggests that phytoextraction decreased the mobility of the metals hyperaccumulated by the plant (Cd and Zn) but increased the mobility of the metals not hyperaccumulated (Cu and Pb). Thus, phytoextraction of soils contaminated with mixtures of metals must be performed carefully because of potential increases in the mobility of non-hyperaccumulated metals in the soil and the consequent environmental risks.
- Published
- 2017
15. Remediation of organochlorine pesticides (OCPs) contaminated site by successive methyl-ฮฒ-cyclodextrin (MCD) and sunflower oil enhanced soil washing โ Portulaca oleracea L. cultivation
- Author
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Mingming Sun, Fredrick Orori Kengara, Xin Jiang, Feng Hu, Yongming Luo, Mao Ye, and Xinlun Yang
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Environmental Engineering ,food.ingredient ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Colony Count, Microbial ,Beta-Cyclodextrins ,Portulaca ,complex mixtures ,Nutrient ,food ,Hydrocarbons, Chlorinated ,Plant Oils ,Soil Pollutants ,Sunflower Oil ,Environmental Chemistry ,Pesticides ,Environmental Restoration and Remediation ,Soil Microbiology ,Bacteria ,biology ,Chemistry ,Sunflower oil ,beta-Cyclodextrins ,Fungi ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Pesticide ,biology.organism_classification ,Pollution ,Environmental chemistry ,Soil microbiology - Abstract
An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs)-contaminated site. Elevated temperature (50 degrees C) combined with ultrasonication (35 kHz, 30 min) at 25 g L-1 methyl-beta-cyclodextrin and 100 mL L-1 sunflower oil were effective in extracting OCPs from the soil. After four successive washing cycles, the removal efficiency for total OCPs, DDTs, endosulfans, 1,2,3,4,5,6-hexachlorocyclohexanes, heptachlors, and chlordanes were all about 99%. The 4th washed soil with 3 months cultivation of Portulaca oleracea L. and nutrient addition significantly increase (p < 0.05) the number, biomass carbon, nitrogen, and functioning diversity of soil microorganisms. This implied that the microbiological functioning of the soil was at least partially restored. This combined cleanup strategy proved to be effective and environmental friendly. (C) 2014 Elsevier Ltd. All rights reserved.
- Published
- 2014
16. PGPR enhanced phytoremediation of petroleum contaminated soil and rhizosphere microbial community response
- Author
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Yongming Luo, Qingling Wang, Beibei Wang, Wuxing Liu, Ashley E. Franks, and Jinyu Hou
- Subjects
Festuca ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Lysobacter ,Bacterial Physiological Phenomena ,complex mixtures ,Petroleum Pollution ,Pseudoxanthomonas ,Botany ,Hydrogenophaga ,Environmental Chemistry ,Soil Pollutants ,Food science ,Biomass ,Rhizosphere ,biology ,Chemistry ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,biology.organism_classification ,Pollution ,Soil contamination ,Hydrocarbons ,Phytoremediation ,Biodegradation, Environmental ,Microbial population biology - Abstract
The aim of this study was to investigate petroleum phytoremediation enhancement by plant growth promoting bacteria (PGPR), specifically the correlation between petroleum hydrocarbon fractions and bacterial community structure affected by remediation and PGPR inocula. Aged petroleum contaminated soil was remediated by tall fescue (Testuca arundinacea L.) inoculated with two PGPR strains. Hydrocarbon degradation was measured by GC-MS (Gas-chromatography Mass-spectrometer) based on carbon fraction numbers (C8-C34). Changes in bacterial community structure were analyzed by high-throughput pyrosequencing of 16s rRNA. PGPR inoculation increased tall fescue biomass and petroleum hydrocarbons were removed in all the treatments. Maximum hydrocarbon removal, particular high molecular weight (C21-C34) aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs), was observed in tall fescue inoculated with PGPR. The relative abundance of phyla ฮณ-proteobacteria and Bacteroidetes increased after different treatments compared with controls. Moreover, a bacterial guild mainly comprising the genera Lysobacter, Pseudoxanthomonas, Planctomyces, Nocardioides, Hydrogenophaga, Ohtaekwangia was found to be positively correlated with C21-C34 petroleum hydrocarbons fractions removal by RDA analysis, implying that petroleum degradation was unrelated to bacterial community diversity but positively correlated with specific petroleum degraders and biosurfactant producers.
- Published
- 2015
17. Fungal degradation of metsulfuron-methyl in pure cultures and soil
- Author
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Yunlong Yu, Yongming Luo, Xiao Wang, De Fang Fan, Ji Feng Yang, and Jing-Quan Yu
- Subjects
Environmental Engineering ,Strain (chemistry) ,Health, Toxicology and Mutagenesis ,Fungi ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Biodegradation ,Pollution ,Soil contamination ,Metsulfuron-methyl ,chemistry.chemical_compound ,Biodegradation, Environmental ,Bioremediation ,chemistry ,Soil water ,Soil Pollutants ,Environmental Chemistry ,Food science ,Arylsulfonates ,Energy source ,Incubation ,Soil Microbiology - Abstract
A fungal strain capable of utilizing metsulfuron-methyl as sole carbon and energy sources was isolated from a metsulfuron-methyl treated soil. The degradation characteristics of metsulfuron-methyl by this fungal strain were investigated in liquid culture and soil. More than 79% of metsulfuron-methyl at concentrations of 0.10 mg l โ1 , 1.0 mg l โ1 and 10.0 mg l โ1 in pure culture was degraded by strain MD after incubation for 7 days, whereas only 5.6%, 8.6% and 13.1% of metsulfuron-methyl were degraded at levels of 0.10 mg l โ1 , 1.0 mg l โ1 and 10.0 mg l โ1 in the controls, respectively. The incorporation of strain MD into soil was found to substantially increase the degradation of metsulfuron-methyl. Degradation was 7.5 and 3.8 times faster in strain MD amended soils than in sterilized and fresh soils. The results show that addition of the isolated strain MD enhances degradation of metsulfuron-methyl in water and soil.
- Published
- 2005
18. Changes in soil microbial biomass and Zn extractability over time following Zn addition to a paddy soil
- Author
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K.Q. Ding, Yongming Luo, Peter Christie, Xinru Jiang, Shugang Wu, Shuang-Shuang Liu, and Qingqing Zhao
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Environmental Engineering ,Soil test ,Health, Toxicology and Mutagenesis ,Acetates ,Risk Assessment ,Soil respiration ,Soil ,Animal science ,Soil pH ,Environmental Chemistry ,Biomass ,Incubation ,Edetic Acid ,Soil Microbiology ,Acetic Acid ,Nitrates ,Chemistry ,Public Health, Environmental and Occupational Health ,Environmental engineering ,Water ,General Medicine ,General Chemistry ,Carbon Dioxide ,Hydrogen-Ion Concentration ,Pollution ,Soil contamination ,Soil quality ,Zinc ,Zinc Compounds ,Respiration rate ,Soil microbiology - Abstract
A laboratory incubation study was conducted using a paddy soil spiked with two quantities of Zn as soluble Zn(NO3)2 and unamended controls. Three single extractants (1 M ammonium acetate (pH 7.0), 0.43 M acetic acid and 0.05 M EDTA) were used to assess the bioavailability of Zn. Biological community assessments were made microbial biomass (chloroform fumigation), soil basal respiration and dehydrogenase activity. During the 84-day period of the experiment, addition of Zn at both 500 and 1,000 mg kg(-1) had little detectable effect on soil pH. The concentration of NH4OAc-extractable Zn decreased rapidly within the initial six weeks. The concentration of HOAc-extractable Zn showed no decrease during 84 days incubation. EDTA-extractable Zn was greater than NH4OAc- and HOAc-extractable fractions, and showed a similar trend to NH4OAc-extractable after incubation. Microbial biomass, soil basal respiration and dehydrogenase activity all decreased over time during 84 days incubation. Addition of Zn resulted in a significant increase in specific respiration (qCO2). Microbial biomass and dehydrogenase activity did not appear to be influenced by added Zn, probably due to the strong buffering capacity of the soil. The Zn extracted by EDTA, HOAc and NH4OAc showed close relationships with each other (p < 0.001). Zinc extracted by 0.05 M EDTA and NH4OAc were highly correlated with soil basal respiration and specific respiration rate (p < 0.01). The results suggest that NH4OAc-extractable Zn combined with soil specific respiration could be used as parameters for risk assessment.
- Published
- 2003
19. Effect of cadmium on nodulation and N2-fixation of soybean in contaminated soils
- Author
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Yongshan Chen, Shao Jian Zheng, Yunlong Yu, Yun Feng He, Yuxuan Yang, Yongming Luo, Guangming Tian, and Ming Hung Wong
- Subjects
Environmental Engineering ,Rhizobiaceae ,Root nodule ,Health, Toxicology and Mutagenesis ,chemistry.chemical_element ,Root system ,Plant Roots ,Nitrogen Fixation ,Soil Pollutants ,Environmental Chemistry ,Cadmium ,biology ,Public Health, Environmental and Occupational Health ,food and beverages ,General Medicine ,General Chemistry ,Ultisol ,biology.organism_classification ,Pollution ,Microscopy, Electron ,Phytoremediation ,Horticulture ,chemistry ,Agronomy ,Nitrogen fixation ,Phytotoxicity ,Soybeans ,Rhizobium - Abstract
The effects of cadmium stress on nodulation, N 2 -fixation capabilities of the root nodule, the change in ultrastructure of the root nodule, soybean growth, and the distribution of cadmium in plants were studied. The results obtained show that the nodulation of soybean roots was greatly inhibited by the addition of Cd, especially at the addition level of 10 and 20 mg kg โ1 soil. The inhibition of plant growth, especially the root growth, increased as the cadmium concentration increased, with deleterious effects observed for the roots. The weight ratio of soybean root/leaf decreased as the Cd concentration increased, which might explain the reason for nodulation decreases. The results also indicate that N 2 -fixation of root nodule was stimulated to some extent at the low levels of Cd addition, but decreased sharply with further increase of the Cd concentration. High Cd levels were also associated with changes in the ultrastructure of root nodule, in which the effective N 2 -fixing area was reduced and the N 2 -fixing cells in the area also reduced. In addition, the results also reveal that the content of Cd in different parts of the plants was as follows: rootsโซstems>seeds, indicating that the accumulation of Cd by roots is much larger than that by any other part of the soybean plant, and might cause deleterious effects to root systems.
- Published
- 2003
20. Novel use of soil moisture samplers for studies on anaerobic ammonium fluxes across lake sedimentโwater interfaces
- Author
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Yongming Luo, Jianzhong Song, Peter Christie, and Qingqing Zhao
- Subjects
China ,Geologic Sediments ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Soil ,Flux (metallurgy) ,Sedimentโwater interface ,Environmental Chemistry ,Anaerobiosis ,Water pollution ,Water content ,Data Collection ,Public Health, Environmental and Occupational Health ,Environmental engineering ,Water ,Sediment ,Humidity ,General Medicine ,General Chemistry ,Hydrogen-Ion Concentration ,Pollution ,Quaternary Ammonium Compounds ,Environmental chemistry ,Environmental science ,Rheology ,Microcosm ,Eutrophication ,Porosity ,Surface water - Abstract
Small soil suction samplers have been used for several years to sample soil solution for chemical analysis in laboratory and glasshouse experiments. They are very cheap, effective and convenient. Here we describe for the first time their use in studies on sediment porewater. Bulk sediment from West Lake, a shallow hypereutrophic lake in Hangzhou, Zhejiang Province, China, was placed in laboratory microcosms and incubated in the dark at 25 degrees C for 182 days to evaluate the feasibility of using the samplers to extract sediment porewater and to estimate NH4+ flux across the sediment-water interface under anaerobic conditions. The results show that the samplers were capable of sequentially extracting sediment porewater, 15 ml of which could be readily extracted for analysis within 30-45 min by vacuum applied using a plastic syringe. The NH4+ flux under laboratory conditions was characterized by a fast phase during the initial 18 days of incubation followed by a slower linear phase, with average release rates of 11.6 and 3.6 mg N m(-2) d(-1), respectively.
- Published
- 2003
21. Rapid degradation of butachlor in wheat rhizosphere soil
- Author
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Xue-Bo Pan, Yun Feng He, Ming Hung Wong, Yongming Luo, Yingxu Chen, and Yunlong Yu
- Subjects
China ,Bioaugmentation ,Rhizosphere ,Environmental Engineering ,Chemistry ,Inoculation ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Plant Roots ,Pollution ,Soil contamination ,Soil ,chemistry.chemical_compound ,Biodegradation, Environmental ,Bioremediation ,Agronomy ,Soil water ,Environmental Chemistry ,Acetanilides ,Poaceae ,Environmental Pollution ,Triticum ,Butachlor - Abstract
The degradative characteristics of butachlor in non-rhizosphere, wheat rhizosphere, and inoculated rhizosphere soils were measured. The rate constants for the degradation of butachlor in non-rhizosphere, rhizosphere, and inoculated rhizosphere soils were measured to be 0.0385, 0.0902, 0.1091 at 1 mg/kg, 0.0348, 0.0629, 0.2355 at 10 mg/kg, and 0.0299, 0.0386, 0.0642 at 100 mg/kg, respectively. The corresponding half-lives for butachlor in the soils were calculated to be 18.0, 7.7, 6.3 days at 1 mg/kg, 19.9, 11.0, 2.9 days at 10 mg/kg, and 23.2, 18.0, 10.8 days at 100 mg/kg, respectively. The experimental results show that the degradation of butachlor can be enhanced greatly in wheat rhizosphere, and especially in the rhizosphere inoculated with the bacterial community designated HD which is capable of degrading butachlor. It could be concluded that rhizosphere soil inoculated with microorganisms-degrading target herbicides is a useful pathway to achieve rapid degradation of the herbicides in soil.
- Published
- 2003
22. Soil Cd availability to Indian mustard and environmental risk following EDTA addition to Cd-contaminated soil
- Author
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Alan J. M. Baker, Ming Hung Wong, Xinru Jiang, Yongming Luo, Peter Christie, and Qingqing Zhao
- Subjects
Environmental Engineering ,Health, Toxicology and Mutagenesis ,Statistics as Topic ,Plant Roots ,Risk Assessment ,complex mixtures ,Soil ,Animal science ,Soil Pollutants ,Environmental Chemistry ,Chelation ,Leaching (agriculture) ,Edetic Acid ,Chelating Agents ,Chemistry ,Public Health, Environmental and Occupational Health ,food and beverages ,General Medicine ,General Chemistry ,Pollution ,Soil contamination ,Phytoremediation ,Agronomy ,Loam ,Soil water ,Shoot ,Environmental Pollutants ,Phytotoxicity ,Plant Shoots ,Cadmium ,Mustard Plant - Abstract
A pot experiment was conducted to investigate the influence of EDTA on the extractability of Cd in the soil and uptake of Cd by Indian mustard (Brassica juncea). Twenty levels of soil Cd concentration ranging from 10 to 200 mg kg(-1) were produced by spiking aliquots of a clay loam paddy soil with Cd(NO3)2. One week before the plants were harvested EDTA was applied to pots in which the soil had been spiked with 20, 40, 60...200 mg Cd kg(-1). The EDTA was added at the rate calculated to complex with all of the Cd added at the 200 mg kg(-1) level. Control pots spiked with 10, 30, 50... 190 mg Cd kg(-1) received no EDTA. The plants were harvested after 42 days' growth. Soil water- and NH4NO3-extractable Cd fractions increased rapidly following EDTA application. Root Cd concentrations decreased after EDTA application, but shoot concentrations increased when the soil Cd levels were130 mg kg(-1) and Cd toxicity symptoms were observed. The increases in soil solution Cd induced by EDTA did not increase plant total Cd uptake but appeared to stimulate the translocation of the metal from roots to shoots when the plants appeared to be under Cd toxicity stress. The results are discussed in relation to the possible mechanisms by which EDTA may change the solubility and bioavailability of Cd in the soil and the potential for plant uptake and environmental risk due to leaching losses to groundwater.
- Published
- 2003
23. Chemical speciation and extractability of Zn, Cu and Cd in two contrasting biosolids-amended clay soils
- Author
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X. L. Qiao, Peter Christie, Ming Hung Wong, and Yongming Luo
- Subjects
Environmental Engineering ,Biosolids ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Amendment ,chemistry.chemical_element ,Acetates ,Soil ,Metals, Heavy ,Soil Pollutants ,Environmental Chemistry ,Anaerobiosis ,Edetic Acid ,Acetic Acid ,media_common ,Cadmium ,Sewage ,Chemistry ,Extraction (chemistry) ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Hydrogen-Ion Concentration ,Pollution ,Soil contamination ,Zinc ,Speciation ,Environmental chemistry ,Soil water ,Clay ,Aluminum Silicates ,Red soil ,Oxidation-Reduction ,Copper - Abstract
An incubation experiment was conducted to study the chemical speciation and extractability of three heavy metals in two contrasting biosolids-amended clay soils. One was a paddy soil of pH 7.8 and the other was a red soil of pH 4.7 collected from a fallow field. Anaerobically digested biosolids were mixed with each of the two soils at three rates: 20, 40 and 60 g kg โ1 soil (DM basis), and unamended controls were also prepared. The biosolids-amended and control soils were incubated at 70% of water holding capacity at 25 °C for 50 days. Separate subsamples were extracted with three single extractants and a three-step sequential extraction procedure representing acetic acid (HOAc)-soluble, reducible and oxidisable fractions to investigate the extractability and speciation of the heavy metals. As would be expected, there were good relationships between biosolids application rate and metal concentrations in the biosolids-amended soils. The three heavy metals had different extractabilities and chemical speciation in the two biosolids-amended soils. Ethylene diamine tetraacetic acid extracted more Cu, Zn and Cd than did the other two single extractants. The oxidisable fraction was the major fraction for Cu in both biosolids-amended soils and the HOAc-soluble and reducible fractions accounted for most of the Zn. In contrast, Cd was present mainly in the reducible fraction. The results are discussed in relation to the mobility and bioavailability of the metals in polluted soils.
- Published
- 2003
24. Assessment of EDTA heap leaching of an agricultural soil highly contaminated with heavy metals
- Author
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Yongming Luo, Pengjie Hu, Jie Zhao, Longhua Wu, Like Chen, Xueying Cao, Changxun Dong, Peter Christie, and Bingfan Yang
- Subjects
Crops, Agricultural ,China ,Environmental Engineering ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Amendment ,Heap leaching ,Pilot Projects ,Metals, Heavy ,Vegetables ,Environmental Chemistry ,Soil Pollutants ,Organic matter ,Leaching (agriculture) ,Kjeldahl method ,Edetic Acid ,Environmental Restoration and Remediation ,chemistry.chemical_classification ,Chemistry ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Pollution ,Loam ,Environmental chemistry ,Soil water ,Environmental Pollution - Abstract
The efficiency of heavy metal removal from soil by EDTA leaching was assessed in a column leaching experiment at the laboratory scale and field heap leaching at the pilot scale using a sandy loam sierozem agricultural soil contaminated with Cd, Cu, Pb, and Zn. Soil amendment and aging were conducted to recover leaching soils. The percentages of Cd, Cu, Pb, and Zn removed by column leaching were 90%, 88%, 90%, and 67%, respectively, when 3.9 bed volumes of 50 mM EDTA were used. At the pilot scale, on-site metal removal efficiencies using the selected leaching procedure were 80%, 69%, 73% and 62% for Cd, Cu, Pb and Zn, respectively. EDTA leaching decreased soil CEC, total P, total K and available K concentrations but increased organic matter and total Kjeldahl N concentrations. The subsequent amendment and soil aging further reduced the DTPA-extractable heavy metals in the leached soils. Growth of the first crop of pak choi in the leached soil was inhibited but the second crop grew well after the soil was aged for one year and the concentrations of Cd and Pb in the edible parts were below the Chinese statutory limits. The results demonstrate the potential feasibility of the field leaching technique using EDTA combined with subsequent amendment and soil aging for the remediation of heavy metal-contaminated agricultural soils. (C) 2014 Elsevier Ltd. All rights reserved.
- Published
- 2014
25. Isolation and characterization of plant growth-promoting rhizobacteria and their effects on phytoremediation of petroleum-contaminated saline-alkali soil
- Author
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Qingling Wang, Wuxing Liu, Jinyu Hou, Linlin Ding, and Yongming Luo
- Subjects
Festuca ,Environmental Engineering ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Molecular Sequence Data ,Biology ,Rhizobacteria ,complex mixtures ,Alkali soil ,Soil ,Bacterial Proteins ,Stress, Physiological ,Klebsiella ,Environmental Chemistry ,Petroleum Pollution ,Carbon-Carbon Lyases ,Rhizosphere ,Inoculation ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Sequence Analysis, DNA ,Pollution ,Soil contamination ,Phytoremediation ,Biodegradation, Environmental ,Agronomy ,Halotolerance ,Environmental Pollution - Abstract
This study aimed to isolate promising halotolerant and alkalotolerant plant growth-promoting rhizobacteria and to study their effects on the growth of tall fescue and phytodegradation efficiency in a petroleum-contaminated saline-alkaline soil. A total of 115 PGPR strains were isolated from the rhizosphere of tall fescue grown in petroleum-contaminated saline-alkaline soils. Of these, 5 strains indicating 1aminocyclopropane-l-carboxylic acid deaminase activity >1.0 M proportional to-KB mg(-1) h(-1) were selected for further studies. The isolate D5A presented the highest plant-growth-promoting activity and was identified as Klebsiella sp. It grew well on the Luria-Bertani medium containing 9% NaCI and at a pH range of 4-10. A pot experiment was then conducted to study the effect of isolates on phytoremediation. The results showed that inoculation of D5A promoted tall fescue growth and enhanced remediation efficiency in petroleum-contaminated saline-alkaline soil. (C) 2014 Elsevier Ltd. All rights reserved.
- Published
- 2014
26. Determination of low levels of polycyclic aromatic hydrocarbons in soil by high performance liquid chromatography with tandem fluorescence and diode-array detectors
- Author
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Mengfang Chen, Yujuan Huang, Jing Wei, Jing Song, and Yongming Luo
- Subjects
Detection limit ,Environmental Engineering ,Chromatography ,Soil test ,Elution ,Chemistry ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Pollution ,Soil contamination ,High-performance liquid chromatography ,Matrix (chemical analysis) ,Congener ,Spectrometry, Fluorescence ,Limit of Detection ,Environmental chemistry ,Soil water ,Environmental Chemistry ,Soil Pollutants ,Polycyclic Aromatic Hydrocarbons ,Chromatography, High Pressure Liquid ,Environmental Monitoring - Abstract
Risk assessment of polycyclic aromatic hydrocarbons (PAHs) contaminated soil and source apportionment require accurate analysis of the concentration of each PAH congener in the soil. However, determination of low level PAH congeners in soil is difficult because of similarity in the chemical properties of 16 PAHs and severe matrix interferences due to complex composition of soils. It is therefore imperative to develop a sensitive and accurate method for determination of low level PAHs in soil. In this work, high performance liquid chromatography equipped with fluorescence and diode-array detectors (HPLC-FLD-DAD) was used to determine the concentration of 16 PAHs in soil. The separation of the 16 PAHs was achieved by optimization of the mobile phase gradient elution program and FLD wavelength switching program. Qualitative analysis of the 16 PM-Is was based on the retention time (RT) and each PAH specific spectrum obtained from DAD. In contrast, the quantitative analysis of individual PAH congeners was based on the peak areas at the specific wavelength with DAD and FLD. Under optimal conditions the detection limit was in the range 1.0-9.5 mu g L-1 for 16 PAHs with DAD and 0.01-0.1 mu g L-1 for 15 PAHs with FLD, and the RSD of PAHs was less than 5% with DAD and 3% with FLD. The spiked recoveries were in the range 61-96%, with the exception of NaP (
- Published
- 2012
27. Use of a multi-layer column device for study on leachability of nitrate in sludge-amended soils
- Author
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Yongming Luo, Xianliang Qiao, Ming Hung Wong, Jing Song, and Peter Christie
- Subjects
Environmental Engineering ,Nitrates ,Soil test ,Sewage ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Environmental engineering ,Soil classification ,General Medicine ,General Chemistry ,Hydrogen-Ion Concentration ,Pollution ,Soil contamination ,Kinetics ,Soil ,Solubility ,Soil water ,Environmental Chemistry ,Soil horizon ,Environmental science ,Soil Pollutants ,Leaching (agriculture) ,Red soil ,Sludge ,Environmental Monitoring - Abstract
This paper described a multi-layer column device constructed with six cylindrical polythene tubes with installation of Rhizon soil moisture samplers (Rhizon SMS). The feasibility of using the column device to collect soil solution and percolate and to monitor leachability of nitrate in two sludge-amended soils was evaluated under glasshouse conditions. The soil moisture sampler in the device was demonstrated to be a non-destructive, simultaneous, sequential, convenient and rapid sampling tool for multiple-site porewater extraction. The device provided an in situ monitoring technique for leachability of nitrate in a soil profile following application of the anaerobically digested sewage sludge. The monitored results showed that surface soil amendment of the sewage sludge increased markedly the concentration of nitrate in the soil solutions at depths of 10-30 cm in a neutral paddy soil and at 30-50 cm in an acid red paddy soil. This amendment also largely increased nitrate in the percolates of the acid red soil. The movement and distribution patterns of nitrate in the profile were related to soil types, profile depths and experimental periods. Land application of sewage sludge may pose a risk in groundwater contamination of nitrate.
- Published
- 2003
28. Effects of EDTA and low molecular weight organic acids on soil solution properties of a heavy metal polluted soil
- Author
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M.H. Wong, Yongming Luo, Longhua Wu, and Peter Christie
- Subjects
Environmental Engineering ,Soil test ,Health, Toxicology and Mutagenesis ,Oxalic acid ,Carboxylic Acids ,Malates ,chemistry.chemical_element ,Plant Roots ,Citric Acid ,chemistry.chemical_compound ,Soil ,Metals, Heavy ,Environmental Chemistry ,Soil Pollutants ,Chelation ,Edetic Acid ,Rhizosphere ,Cadmium ,Oxalic Acid ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Hydrogen-Ion Concentration ,Pollution ,Soil contamination ,Carbon ,Molecular Weight ,Zinc ,chemistry ,Lead ,Environmental chemistry ,Malic acid ,Citric acid ,Copper ,Mustard Plant - Abstract
A pot experiment was conducted to study the effects of EDTA and low molecular weight organic acids (LMWOA) on the pH, total organic carbon (TOC) and heavy metals in the soil solution in the rhizosphere of Brassica juncea grown in a paddy soil contaminated with Cu, Zn, Pb and Cd. The results show that EDTA and LMWOA have no effect on the soil solution pH. EDTA addition significantly increased the TOC concentrations in the soil solution. The TOC concentrations in treatments with EDTA were significantly higher than those in treatments with LMWOA. Adding 3 mmol kg(-1) EDTA to the soil markedly increased the total concentrations of Cu, Zn, Pb and Cd in the soil solution. Compared to EDTA, LMWOA had a very small effect on the metal concentrations. Total concentrations in the soil solution followed the sequence: EDTA >> citric acid (CA) approximately oxalic acid (OA) approximately malic acid (MA) for Cu and Pb; EDTA >> MA >> CA approximately OA for Zn; and EDTA >> MA >> CA > OA for Cd. The labile concentrations of Cu, Zn, Pb and Cd showed similar trends to the total concentrations.
- Published
- 2003
29. Soil solution Zn and pH dynamics in non-rhizosphere soil and in the rhizosphere of Thlaspi caerulescens grown in a Zn/Cd-contaminated soil
- Author
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Peter Christie, Yongming Luo, and Alan J. M. Baker
- Subjects
Environmental Engineering ,Health, Toxicology and Mutagenesis ,Bulk soil ,Plant Roots ,Soil pH ,Environmental Chemistry ,Soil Pollutants ,Hyperaccumulator ,Tissue Distribution ,Rhizosphere ,biology ,Chemistry ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Hydrogen-Ion Concentration ,Plants ,biology.organism_classification ,Pollution ,Soil contamination ,Phytoremediation ,Zinc ,Agronomy ,Thlaspi caerulescens ,Cadmium - Abstract
Temporal changes in soil solution properties and metal speciation were studied in non-rhizosphere soil and in the rhizosphere of the hyperaccumulator Thlaspi caerulescens J. & C. Presl (population from Prayon, Belgium) grown in a Zn- and Cd-contaminated soil. This paper focuses on soil solution Zn and pH dynamics during phytoextraction. The concentration of Zn in both non-rhizosphere and rhizosphere soil solutions decreased from 23 mg/l at the beginning to 2 mg/l at the end of the experiment (84 days after transplanting of seedlings), mainly due to chemical sorption. There was no significant difference in overall Zn concentration between the planted and the unplanted soil solutions (P > 0.05). Soil solution pH decreased initially and then increased slightly in both planted and unplanted soil zones. From 60 to 84 days after transplanting, the pH of the rhizosphere soil solution was higher than that of non-rhizosphere soil solution (P
- Published
- 2000
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