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1.
Gil C  Boluda R  Ramos J 《Chemosphere》2004,55(7):1027-1034
This study determines total levels of three (Cd, Pb and Ni) potentially toxic trace elements in western Almería (Spain) greenhouse surface soil horizons using microwave digestion; it establishes the geochemical baseline concentration, and it investigates possible relationships between soil properties and elemental concentrations. The results show that the soil concentration of these heavy metals is lower than mentioned in the European and Spanish normative, but they are higher than those reported by other authors working on agricultural soils. The obtained geochemical baseline concentrations (mg kg(-1)) were: Cd 0.4-0.8, Pb 2.5-89.9 and Ni 16.1-30.7. Using the upper baseline criterion, 88% of greenhouse soils have relatively higher content of heavy metals because of their Cd, Pb and Ni concentration. Moreover, soil properties are related to heavy metals contents suggesting that among Cd, Pb and Ni have a similar origin and those total metal concentrations are controlled primarily by soil compositions.  相似文献   

2.
Soil contamination with anthropogenic metals resulting from biosolid application is widespread around the world. To better predict the environmental fate and mobility of contaminants, it is critical to study the capacity of biosolid-amended soils to retain and release metals. In this paper, nickel adsorption onto a calcareous soil, a lime-stabilized biosolid, and soil–biosolid mixtures (30, 75, and 150 t biosolid/ha) was studied in batch experiments. Sorption experiments showed that (1) Ni adsorption was higher onto the biosolid than the calcareous soil, and (2) biosolid acted as an adsorbent in the biosolid–soil mixtures by increasing Ni retention capacity. The sorption tests were complemented with the estimation of Ni adsorption reversibility by successive applications of extraction solutions with water, calcium (100 mg/L), and oxalic acid (equivalent to 100 mg carbon/L). It has been shown that Ni desorption rates in soil and biosolid-amended soils were lower than 30 % whatever the chemical reagent, indicating that Ni was strongly adsorbed on the different systems. This adsorption/desorption hysteresis effect was particularly significant at the highest biosolid concentration (150 t/ha). Finally, an adsorption empirical model was used to estimate the maximum permissible biosolid application rate using French national guideline. It has been shown that desorption effects should be quantitatively considered to estimate relevant biosolid loadings.  相似文献   

3.
Landfill gas (LFG) management is one of the most important tasks for landfill operation and closure because of its impact in potential global warming. The aim of this work is to present a case history evaluating an LFG capture and treatment system for the present landfill facility in Córdoba, Argentina. The results may be relevant for many developing countries around the world where landfill gas is not being properly managed. The LFG generation is evaluated by modeling gas production applying the zero-order model, Landfill Gas Emissions Model (LandGEM; U.S. Environmental Protection Agency [EPA]), Scholl Canyon model, and triangular model. Variability in waste properties, weather, and landfill management conditions are analyzed in order to evaluate the feasibility of implementing different treatment systems. The results show the advantages of capturing and treating LFG in order to reduce the emissions of gases responsible for global warming and to determine the revenue rate needed for the project’s financial requirements. This particular project reduces by half the emission of equivalent tons of carbon dioxide (CO2) compared with the situation where there is no gas treatment. In addition, the study highlights the need for a change in the electricity prices if it is to be economically feasible to implement the project in the current Argentinean electrical market.

Implications: Methane has 21 times more greenhouse gas potential than carbon dioxide. Because of that, it is of great importance to adequately manage biogas emissions from landfills. In addition, it is environmentally convenient to use this product as an alternative energy source, since it prevents methane emissions while preventing fossil fuel consumption, minimizing carbon dioxide emissions. Performed analysis indicated that biogas capturing and energy generation implies 3 times less equivalent carbon dioxide emissions; however, a change in the Argentinean electrical market fees are required to guarantee the financial feasibility of the project.  相似文献   


4.
Environmental Science and Pollution Research - This study examines China’s budgetary policy during the COVID-19 pandemic as a result of China’s insufficient ability to deal with a new...  相似文献   

5.
Environmental Science and Pollution Research - The heavy metal contamination of soil and groundwater is a serious threat to environment worldwide. The survival of human being primarily relies upon...  相似文献   

6.
The present work compares the efficiency of homogenous Fenton and photo-Fenton processes in the presence of Fe(III)–EDDS complex under different experimental conditions. 4-tert-Butylphenol (4-t-BP), which is one of the endocrine disrupting chemicals, was used as a model pollutant to investigate the Fenton and photo-Fenton application. The efficiency of homogenous photo-Fenton process was significantly much higher than homogenous Fenton process, which is due to the rapid formation of Fe2+ under UV irradiation of the iron complex and the photochemical formation of HO? from the photolysis of the complex Fe(III)–EDDS. Through the degradation of 4-t-BP, the effect of Fe(III)–EDDS concentration, H2O2 concentration, pH, and oxygen was investigated in both processes. Such trend was also correlated with pH calculating the polychromatic Fe2+ quantum yield formation at pH 4.0, 6.0, and 8.6. The results showed that at high Fe(III)–EDDS and H2O2 concentrations, a negative effect was found. By the way, the Fenton process was found to be enhanced at basic pH. These results can be very useful for the use and optimization of such iron complex in water treatment process as function of different physico-chemical conditions.  相似文献   

7.
Environmental Science and Pollution Research - A sectorial approach for assessing heavy metal pollution in rivers neglects the inter-relationship between its environmental compartments and thus...  相似文献   

8.
The results of an interdisciplinary research program on the subsurface persistence and transport of pathogenic bacteria and viruses are evaluated on the basis of an expanded advection-dispersion model which considers the persistence of these microorganisms under the conditions found within an aquifer, the retardation by adsorption-desorption processes and the role of filtration processes. The model indicates that the principal controls are filtration processes, the microorganisms being fixed on the filter media are ultimately eliminated or inactivated by biological, chemical and physical processes.  相似文献   

9.
Environmental Science and Pollution Research - This study firstly aimed to investigate the potential of simultaneous metal (loid) removal from metal (oid) solution through adsorption on iron-peat,...  相似文献   

10.
Published estimates for base metal emissions from the copper–nickel industry on the Kola Peninsula are re-examined in the light of (a) chemical data on the composition of the ores; (b) official emission figures for 1994; and (c) modelled emissions based on dry and wet deposition estimates derived from data for snow and rain samples collected in 1994. The modelled emissions, official emission figures and chemical data are mutually compatible for Ni, Cu and Co and show that previously published figures underestimated the emissions of the major elements, Ni and Cu (though within the same order of magnitude) and overestimated the emissions of As, Pb, Sb and Zn by up to several orders of magnitude, in some cases exceeding the calculated total input to the plants. Published estimates have neglected information on the nature and chemistry of the ores processed in metallurgical industries in the Noril'sk area of Siberia and the Urals. Revised emission estimates for 1994, using knowledge of the chemistry of the ores, are proposed: taken with published information on total emissions up to 2000 these data give an indication of emission levels in more recent years.  相似文献   

11.
Plant communities on plots with different metal pollution levels were compared in a field study in order to select the most suitable plant species for the direction of secondary succession toward the targeted grassland vegetation. The vegetational succession showed a gradual increase in plant cover and the number of plant species on the less polluted locations. Two predominant grass species Calamagrostis varia and Sesleria caerulea were selected for phytostabilisation, but a severely reduced seed germination capacity obstructed their use in practice. The mycorrhizal succession showed a gradual replacement of non-mycorrhizal with mycorrhizal plant species. Similar levels of arbuscular mycorrhizal colonisation of a particular plant species may be developed within each growing season regardless of the levels of pollution, with the exception of vesicle/intraradical spore formation. The results suggest that lower overall mycorrhizal colonisation levels and increased vesicle/spore formation may be a part of a mycorrhizal strategy at the most polluted locations.  相似文献   

12.
Environmental Science and Pollution Research - Metal–organic frameworks (MOFs) are a polymer hybrid family of compounds comprising metal ions that have been deliberately incorporated in...  相似文献   

13.
Environmental Science and Pollution Research - Heavy metals is a collective term describing metals and metalloids with a density higher than 5 g/cm3. Some of them are essential...  相似文献   

14.
Mineral phases and their content were determined in attic dust samples collected from 27 houses in the Tikve? Valley, Republic of Macedonia. By using quantitative X-ray diffraction, the principal mineral phases were determined to be the serpentinite group (chrysotile, lizardite) and amphibole group of minerals (ribecite, tremolite, actinolite) present in the attic dust samples from this region which are not common constituents of urban dust. Strong correlations existed between these mineral phases in the dust and those in ores processed at a ferronickel smelter plant situated in this region. Spatial distributions of specific mineral phases were made and were consistent with wind directions and predicted deposition (60–70 %) of dust emitted from the metallurgical plant.  相似文献   

15.
The area included in the present investigation is that surrounding Ziqlab dam in the northern Jordan Valley. The water chemistry of the impounded lake shows that it is dominated by Mg, Ca, Na and HCO3. These waters reflects the dominance of carbonate weathering with some contribution of silicates. Mg + Ca + Na and HCO3 + Cl account for about 90% of the total cations and anions. X-ray analysis shows that, kaolinte and illite are the dominant clay minerals in sediments behind Ziqlab dam. Anthropogenic activities within the Ziqlab catchments area contribute to increasing of the ionic concentrations. These include various development activities in the catchments area, waste disposal (especially the untreated municipal and domestic sewage) into the Ziqlab River, and agricultural activities. Ziqlab dam water chemistry is within the range of stability field of kaolinite.  相似文献   

16.
Ten aircraft-collected cascade impactor samples from the North American Arctic were analyzed using analytical electron microscopy. Morphological, mineralogical and elemental information were obtained from individual particles, as well as compositional data and size distribution estimates of the bulk aerosol. Categorization of carbonaceous material into organic-type and combustion-type carbon particles was performed in this study. This was accomplished through the use of a new ultra-thin window X-ray spectrometer, which can directly detect carbon X-rays emitted from particles, and through interpretation of morphological and electron diffraction data. Verification of graphite as a specific carbon mineral phase present in Arctic soot particles was performed in this manner.Several classes of particles were present in most of the aerosol samples and size fractions. These included liquid H2SO4 droplets, which were always present in the highest numbers, and crustal-type and composite SO4−2 particles. A small fraction (0–30%) of a random sampling of SO2−4particles from all impactor stages were found to contain detectable nitrogen, suggesting that partial neutralization by NH3 may have occurred in this minority of the SO2−4 droplets. Particles rich in non-combustion carbon and thought to be composed of organic material were also observed in most samples. Haze samples collected off the coast of Alert, NWT, show moderate loadings of H2SO4 droplets. Judging from these loadings and those from higher-altitude samples, ambient aerosol particle concentrations must have been considerably higher in the haze. The extent to which local activity at Alert has influenced these haze samples is not known, although a major contribution is not expected. Stratospheric samples did not contain several classes of particles thought to have major anthropogenic source inputs to the Arctic, such as black carbon and coal-fired combustion spheres. The lightest particle loadings in any samples were collected in the upper troposphere near the tropopause, where condensation nuclei counts during sampling fell to as low as 10 cm−3.  相似文献   

17.
Environmental Science and Pollution Research - Long-term exposure to environmental neurotoxic metals is implicated in the induction of dementia and cognitive decline. The present study aims to...  相似文献   

18.
Environmental Science and Pollution Research - To mitigate environmental pollution caused by the escape of dust during coal storage and transportation, humic acid (HA) and grafted acrylamide (AM)...  相似文献   

19.
Environmental Science and Pollution Research - Since renewable energy is essentially non-carbohydrate in nature, it can generate little or no pollutants and can therefore help in achieving both...  相似文献   

20.
Abstract

The landfill of Morelia, the capital city of the state of Michoacán in central-western Mexico, is located 12 km west of the city and has operated since 1997 without a structure engineered and designed to control the generation in situ of biogas and leachates. A geological evaluation of the landfill site is presented in this paper. The results indicate that the site lacks ideal impermeable sub-surface strata. The subsurface strata consist of highly fractured basaltic lava flows (east-west fault and fracture system trend) and sand-size cineritic material with high permeability and porosity. Geochemical analysis of groundwater from Morelia’s municipal aquifer shows a high concentration of heavy metals (Cd, Pb, As) exceeding the Mexican environmental regulations, along with the presence of some organic pollutants (phenols). Analyses of samples of the landfill’s permanent leachate ponds show very high concentrations of the same contaminants. Samples were taken from the leachate pond and from nearby water-wells during the rainy season (summer 1997) and the dry season (spring 1997, 1998, and 1999). In all cases, the concentration of contaminants registered exceeded the standards for drinking water of the World Health Organization (American Public Health Association, American Water Works Association, and Water Pollution Control Federation, 2000). Some metal contaminants could be leaching directly from the landfill.  相似文献   

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