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Effect of Composting Process on Some Chemical-Biological Properties and Heavy Metals Behavior of Municipal Sewage Sludge as Affected by Various Bulking Agents 全文
2020
Saffari, M. | Saffari, V. R. | Khabazzadeh, H. | Naghavi, H.
The present study tries to investigate the effect of composting process on some properties and heavy metals status of two municipal sewage sludge (MSS) as affected by three different organic bulking agents (BAs) at three levels (10%, 25%, and 45% V/V). According to the results, the composting process could reduce the fecal coliform to class A, a reduction more obvious in treatments with BAs than produced composts without them. Changes in the chemical properties of the composts vary according to the type of MSS and Bas. Based on the compost quality standard, most of the produced samples are classified in compost-class II. Examination of the total form of three heavy metals (HMs: Zn, Ni, Fe) of both MSS shows that composting process without BAs increases the HMs total concentration, but using of BAs have not been clear trends. In the contrary, BAs application reduced the available form of Fe and Ni, but increased the Zn available form. Examination of chemical forms of each studied HMs also shows that the composting process reduces the Ni and Fe mobility factor, but increases that of Zn. Generally, while, prepared composts can classify into the compost-class II, based on their properties, the high concentration of total Zn above the standard limit makes it extremely restrictive to be used as class II compost. However, according to EPA regulations, the composts with this concentration of Zn can be used as a relatively safe organic material on agricultural land.
显示更多 [+] 显示较少 [-]Bio-Accumulation of Lead and Cadmium by Radish (Raphanus sativus) and Cress (Lepidium sativum) under Hydroponic Growing Medium 全文
2020
Hedayatzadeh, F. | Banaee, M. | Shayesteh, K.
In order to investigate the accumulation and bio-absorption of lead and cadmium in radish and cress, the present study has been conducted in a completely randomized design in three replicates in a hydroponic growing medium. The first factor includes the plant type at two levels (radish and cress), and the second factor is consisted of lead (Pb) (first experiment) at two levels (50 and 100 mg/L), cadmium (Cd) (second experiment) at one level (10 mg/L), and a combination of lead and cadmium (third experiment) again at two levels. After 23 days, roots and aerial parts of both plants have been dried for 48 hours at 70°C in an oven. Then, half gram (0.5 g) of the dried templates has been used to measure the accumulation of Pb and Cd by means of an atomic absorption spectrometer. The highest amount of Pb in radish and crest roots belong to 100 mg/L concentration and the combined Cd (10) + Pb (100) mg/L treatment, respectively, and the highest amount of Cd occurs in Cd (10) + Pb (50) for radish roots and in Cd (10) + Pb (100) combination for cress. Moreover, the Translocation Factor (TF), with a value below 1 and higher bio-concentration factor (BCF) in roots, compared to the aerial part of both radish and cress, seem to be due to the low capability of these plants to transfer Pb and Cd from roots to aerial part. There is a high potentiality for lead accumulation in the roots that prevent its transfer to the aerial part.
显示更多 [+] 显示较少 [-]Effect of Barley and Oat Plants on Phytoremediation of Petroleum Polluted Soils 全文
2020
Barati, M. | Safarzadeh, S. | Mowla, D. | Bakhtiari, F.
Total Petroleum Hydrocarbons (TPHs) are one of the most dangerousorganic contaminants in the environment. Therefore, the remediation of the oilcontaminatedsoil is necessary. The growth of barley and oat plant was studied in thecontaminated soils (4, 6, 8% TPHs) during 5 months. Plant height, wet and dry weight ofshoots and roots of both plants were measured. Results showed that oat and barley height,wet and dry weight of shoots and roots decreased with increasing contamination levels.Regardless of the plants species, the highest rate of TPH reduction was observed in soilwith 4% contamination and decreased with increasing the contamination level. The TPHsconcentration in the rhizosphere of barley and oat decreased by 29.66 and 24.04% at the6% TPHs level and by 21.24 and 17.48% at the 8% TPHs level, respectively. Cultivationof barley and oat plants significantly accelerated the biodegradation of hydrocarbons andreduced TPHs content in soil as compared to unplanted soil.
显示更多 [+] 显示较少 [-]Emissions and Fuel Life Cycle Assessment of Non-passenger Diesel Vehicles in Qatar 全文
2020
Al-Thani, H. | Al-Ghamdi, S. | Koc, M. | Isaifan, R. j.
The life cycle of diesel fuel in non-passenger vehicles was assessed for all registered vehicles in Qatar as of November 2017. The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model was used as a source of normalized data to evaluate diesel fuel emissions for all non-passenger vehicle categories. This work aims at estimating the emissions from all non-passenger diesel vehicles in Qatar and evaluating the impact of the fuel life cycle assessment. The emissions of CO2, NOx, CO, SO2, VOC, black carbon (BC), organic carbon, fine particulates PM2.5, and coarse particulates PM10 were evaluated. SO2 emissions were found to be dominant during the well to pump (WTP) stage of the life cycle assessment (LCA) process, while the pump to wheel (PTW) stage was found to be dominated by CO, VOC, PM10, PM2.5, and BC emissions. NOx and organic carbon emissions were virtually the same during both stages. Total greenhouse gas emissions amounted to 5367 kt of CO2 equivalent (CO2-eq) in 2017 as compared with that in 2014 (5277 kt), the only reported value in Qatar for transportation emissions. In addition, several mitigation strategies are proposed to ensure sustainability in the transport sector and to minimize the negative impact of diesel fuel emissions in the country.
显示更多 [+] 显示较少 [-]Algal Indices as a Biomonitoring Tool to Assess Eutrophication in the Urban Ponds: a Case Study 全文
2020
Vishal, R. | Meeta, B.
Eutrophication of the urban water bodies is one the biggest challenge causing severe ecological and economic loss. Urban ponds are more prone to eutrophication due to their small size and polluted catchment areas. Biomonitoring using phytoplankton provides cost-effective estimation of the level of eutrophication. Ten urban ponds in different areas of the Mumbai city were chosen to investigate the phytoplankton community structure, and level of eutrophication. We assessed the 3 algal indices viz. Shannon-Wiener indices, Palmer and Nygard's (Myxophycean and diatom) indices. Linear relationship of these indices was tested against Carlson trophic state indices in order to assess the effectiveness of these indices to measure the degree of eutrophication in urban lakes. All ten lakes were found to be eutrophic, of which two were very low eutrophic (TSI – 53.74-53.95), four were low-mid eutrophic (TSI – 55.18 – 57.5), and four lakes were mid eutrophic (TSI 61.4 – 62.2). Shannon-Wiener indices (r= -0.73) and Myxophycean indices (r= 0.77) showed strong correlation with TSI whereas Diatom indices (r= -0.12) and Palmer’s Algal Pollution Indices (r= - 0.47) showed weak correlation with TSI. Thus study found that Shannon-Wiener indices and Myxophycean indices are reliable and cost effective means to assess the eutrophication of urban ponds in Mumbai.
显示更多 [+] 显示较少 [-]Analyses and Pollution Potential of heavy metals at The Jerangau-Jabor Landfill in Kuantan, Malaysia 全文
2020
How F., N. F. | Mohd Noh, N. S. | Nordin, N. A. | Abang Sapani, D. F. N.
The impact of Industrialization has always been related to the better economic and social transformation. However, it should be well planned for environmental sustainability. Landfilling is the most used municipal solid waste (MSW) disposal method in Malaysia. Raw and treated leachate collected from Jerangau-Jabor Landfill Site (JJLS), Kuantan, Pahang were analysed for the content of silver, cadmium, chromium, copper, iron, lead, zinc using Flame Atomic Absorption Spectrometry (FAAS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The metal analyses result were compared with standard limits from the Environmental Quality (Control of Pollution from Solid Waste Transfer Station and Landfill) Regulations 2009, Malaysian Environmental Quality Act 1974 (Act 127) set by the Department of Environment, Ministry of Natural Resources and Environment, Malaysia and used to calculate the sub-leachate pollution index of heavy metals (sub-LPIhm) to evaluate the pollution potential of the heavy metals. The sub-LPIhm is one of the sub-index needed to calculate the Leachate Pollution Index (LPI) together with the sub-LPI organic (sub-LPIorg) and sub-LPI inorganic (sub-LPIinorg). LPI is the level of leachate pollution potential of a landfill site. All the heavy metals in the raw leachate were significantly higher than the treated leachate. Some were found to be above the permissible standard limit stipulated in the regulation. However, the sub-LPIhm showed that the level of heavy metal pollution potential of the leachate is low. It is recommended that the treated leachate should undergo continuous treatment to ensure the discharge leachate complied with the standard limit.
显示更多 [+] 显示较少 [-]Phytoremediation of soil Contaminated by Heavy Metals within a Technical Landfill Center Vicinity: Algerian Case Study 全文
2020
Boukaka, Kh. | Mayache, B.
The contamination of environment with heavy metals has become a serious problem which can affect the human health. Three heavy metals (Zn, Cd and Pb) were determined in soil and plants for below and aboveground parts along landfill Demina center, located in the wilaya of Jijel, Algeria to evaluate their behavior and uptake by Ditrichia viscosa, Juncus effusus and Solanum nigrum. In our research we tried to study the capacity of these spontaneous plants to accumulate and to translocate heavy metals from soil to their tissues during three years. The heavy metals examined in the soils of the study area showed variations in concentrations, the study area may be practically unpolluted with Zn and Pb (CF; 0.45 and 0.98 successively) and very contaminated with Cd (CF; 8.53). According to the results obtained, the soil is uncontaminated with lead (Igeo=-0.60) and zinc (Igeo= -1.42) but it is heavily contaminated with cadmium (Igeo=2.5) along the study area. Overall the BCFS (bioconcentration factors) are superior to 1, for the all heavy metals and species. However, BCFs follow the following order; BCFZn>BCFPb>BCFCd for Ditrichia viscosa, the following order BCFPb>BCFZn>BCFCd for Juncus effuses and follow the following order; BCFZn>BCFCd>BCFPb for Solanum nigrum. The TFs (translocation factor) of the present study showed that Solanum nigrum can translocate the three of the metals into their aboveground parts.
显示更多 [+] 显示较少 [-]Physiological and Growth Responses to Pollutant-Induced Biochemical Changes in Plants: A Review 全文
2020
Mulenga, C. | Clarke, C. | Meincken, M.
Physiological and Growth Responses to Pollutant-Induced Biochemical Changes in Plants: A Review 全文
2020
Mulenga, C. | Clarke, C. | Meincken, M.
Industrial activities compromise the ambient air quality at a local, regional and global level through gaseous and dust emissions. This study reviews uptake mechanisms and the associated phytotoxicity of pollutants in plants, focusing on heavy metals and SO2. It further describes detoxification mechanisms and the resultant biochemical and physiological changes in plants. Finally, the morpho-physiological and growth responses to stress-induced biochemical changes are discussed. Heavy metals and SO2 enter the plant tissue through the stomata, cuticular layers, lenticels and root hairs. In the plant cells, SO2 converts to SO32- or SO42- ions upon reacting with water molecules, which in excess are toxic to plants. However, the detoxification process of SO32- increases the production of reactive oxygen species (ROS). ROS are toxic to plants and damages biomolecules such as lipids, proteins, carbohydrates and DNA. On the other hand, heavy metals, such as Cu and Fe catalyse the Fenton/Haber-Weiss reactions, breaking down H2O2 into OH•. Additionally, Pb and Zn inhibit the activities of ROS-detoxifying enzymes, while other heavy metals bind to cellular layers making them rigid, thereby reducing cell division. Therefore, pollutant toxicity in plants affects biochemical parameters damaging organic molecules and limiting cambial activity. Damaged biomolecules inhibit the plant's capacity to carry out physiological functions, such as photosynthesis, stomatal functions, transpiration and respiration while impaired cambial activity reduces cell division and elongation resulting in reduced plant growth and productivity.
显示更多 [+] 显示较少 [-]Physiological and growth responses to pollutant-induced biochemical changes in plants : a review 全文
2020
Mulenga, C. | Clarke, C. | Meincken, M.
CITATION: Mulenga, C., Clarke, C. & Meincken, M. 2020. Physiological and growth responses to pollutant-induced biochemical changes in plants : a review. Pollution, 6(4):827-848, doi:10.22059/poll.2020.303151.821. | The original publication is available at https://jpoll.ut.ac.ir | ENGLISH ABSTRACT: Industrial activities compromise the ambient air quality at a local, regional and global level through gaseous and dust emissions. This study reviews uptake mechanisms and the associated phytotoxicity of pollutants in plants, focusing on heavy metals and SO2. It further describes detoxification mechanisms and the resultant biochemical and physiological changes in plants. Finally, the morpho-physiological and growth responses to stress-induced biochemical changes are discussed. Heavy metals and SO2 enter the plant tissue through the stomata, cuticular layers, lenticels and root hairs. In the plant cells, SO2 converts to SO32- or SO42- ions upon reacting with water molecules, which in excess are toxic to plants. However, the detoxification process of SO32- increases the production of reactive oxygen species (ROS). ROS are toxic to plants and damages biomolecules such as lipids, proteins, carbohydrates and DNA. On the other hand, heavy metals, such as Cu and Fe catalyse the Fenton/Haber-Weiss reactions, breaking down H2O2 into OH•. Additionally, Pb and Zn inhibit the activities of ROS-detoxifying enzymes, while other heavy metals bind to cellular layers making them rigid, thereby reducing cell division. Therefore, pollutant toxicity in plants affects biochemical parameters damaging organic molecules and limiting cambial activity. Damaged biomolecules inhibit the plant's capacity to carry out physiological functions, such as photosynthesis, stomatal functions, transpiration and respiration while impaired cambial activity reduces cell division and elongation resulting in reduced plant growth and productivity. | https://jpoll.ut.ac.ir/article_78852.html | Publisher's version
显示更多 [+] 显示较少 [-]Taguchi Optimization of Adsorptive Treatment of Effluent from Lead-acid Battery Recycling unit Using Pressmud-a Sugar Industry Waste 全文
2020
Meshram, S. | Thakur, C. | Soni, A. B.
Lead-acid battery recycling is one of the organized process which helps in overcoming the demand of lead for the production of the storage batteries. During recycling, a large amount of effluent is generated which contains lead beyond the permissible limit and harmful for the environment. This effluent was treated by adsorption as an alternative technique by using another waste (pressmud) as an adsorbent obtained from the sugar industry. Properties of the pressmud were determined through Fourier transform infrared spectroscopy, scanning electron microscope and X-ray diffraction analysis. Taguchi method L16 orthogonal array (4^3) was used for batch adsorption study for the parameters, initial pH, adsorbent dose and contact time. The optimum value for the adsorption of Pb(II) onto pressmud was found at effluent pH 4.5, adsorbent dose 1.0 g/50mL and time 240 min from the Signal-to-Noise ratio analysis. Kinetic and isotherm studies were also carried out to understand the mechanism of adsorption. Langmuir isotherm fitted best to the experimental data with R2=0.994 and kinetics of adsorption followed the pseudo-second-order model with R2=0.993.
显示更多 [+] 显示较少 [-]Pb phytostabilization by fast-growing trees inoculated with Pb-resistant plant growth-promoting endophytic bacterium 全文
2020
Yongpisanphop, Jiraporn | Babel, S. | Kruatrachue, M. | Pokethitiyook, P.
Inoculation of endophytic bacteria has been accepted as a promising technique to assist phytostabilization of heavy metal-contaminated soils. This study investigated the effects of inoculating a bacterial strain closely related to Pseudomonas pyschrophila on the plant growth, and phytostabilization of fast-growing trees Acacia mangium and Eucalyptus camaldulensis, growing on artificial spiked soil with Pb up to 1500 mg/kg. After 60 days, the results showed that the strain closely related to P. pyschrophila slightly increased Pb bioavailability and Pb uptake by A. mangium, compared to non-inoculated controls. It slightly reduced Pb bioavailability in soil, but it did not affect the Pb uptake by E. camaldulensis, compared to non-inoculated controls. Interestingly, it was able to significantly increase Pb content in shoots by 3.07-fold in A. mangium and 2.95-fold in E. camaldulensis, compared to non-inoculated controls. Although the inoculation of the strain closely related to P. pyschrophila slightly increased the translocation factor (TF) of Pb in both tree species, their TF values were less than 1. This indicates that plants associated with the strain closely related to P. pyschrophila are suitable for phytostabilization of A. mangium, which may be used for cleaning up Pb contaminated sites. This strain displayed different influences on plant species and was found not suitable for phytostabilization of E. camaldulensis.
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