Complex environmental conditions like heavy metal contamination and elevated CO concentration may cause numerous plant stresses and lead to considerable crop losses worldwide. Cadmium is a non-essential element and potentially highly toxic soil metal pollution, causing oxidative stress in plants and human toxicity. In order to assess a combination of complex factors on the responses of two genotypes of Festuca arundinacea (75B and 75C), a greenhouse experiment was conducted on plants grown in two Cd-contaminated soil conditions and two soil textures under combined effects of elevated ambient CO (700 ppm) and Epichloë endophyte infection.
View Article and Find Full Text PDFWater protection and bioremediation strategies in the vadose zone require understanding the factors controlling bacterial transport for different hydraulic conditions. Breakthrough experiments were made in two different flow conditions: i) an initial bacteria pulse under ponded infiltration into dry sand (-15,000 cm); ii) a second bacteria pulse into the same columns during subsequent infiltration in constant water content and steady-state flow. Escherichia coli (E.
View Article and Find Full Text PDFA total of 167 samples of agricultural soil, atmospheric dust and food crops (wheat and maize) were collected, and four heavy metals, including Zn, Cu, Ni, and Cr, were analyzed for their concentrations, pollution levels and human health risks. The mean heavy metal contents in the agricultural soil and atmospheric dust were exceeds background values and lower than their IEQS (Iranian Environmental Quality Standard) with an exception of Ni. A pollution assessment by Geo-accumulation Index (I) showed that the pollution levels were in the order of Ni> Cu> Cr> Zn for agricultural soils and Ni> Cu> Zn> Cr for atmospheric dust.
View Article and Find Full Text PDFMany reports have already been published regarding the removal of heavy metals from aqueous solutions onto activated carbon. However, the biosorbents' effect on the plant response still needs further investigation. In this study, activated carbon derived from the pomegranate peel [pomegranate activated carbons (PAC)] was used to see the effects of the addition of PAC on growing strawberry in Cd-contaminated sand.
View Article and Find Full Text PDFIt is important to study the status and trend of soil contamination with trace elements to make sustainable management strategies for agricultural soils. This study was conducted in order to model zinc (Zn), copper (Cu), and nickel (Ni) accumulation rates in agricultural soils of Kermanshah province using input and output fluxes mass balance and to evaluate the associated uncertainties. The input and output fluxes of Zn, Cu, and Ni into (from) the agricultural soils of Kermanshah province via livestock manure, mineral fertilizers, municipal waste compost, pesticides, atmospheric deposition, and crop removal were assessed for the period 2000-2014.
View Article and Find Full Text PDFThe objective of this study was to evaluate the effects of pyrolysis temperatures (300, 400, 500, 600 and 700°C) on properties of biochar produced from an urban sewage sludge. Biochar yield significantly decreased from 72.5% at 300°C to 52.
View Article and Find Full Text PDFThe effect of Neotyphodium endophytes on growth parameters and zinc (Zn) tolerance and uptake was studied in two grass species of Festuca arundinacea and Lolium perenne. Plants were grown under different Zn concentrations (control, 200, 400, 800, and 1800 mg kg(-1)) in potted soil for 5 months. The results showed that the number of plant tillers was 85 and 51% greater in endophyte infected Festuca (FaEI) and Lolium (LpEI), respectively, compared to their endophyte free (EF) plants.
View Article and Find Full Text PDFZinc (Zn) deficiency is a major problem for many people living on wheat-based diets. Here, we explored whether addition of green manure of red clover and sunflower to a calcareous soil or inoculating a non-indigenous arbuscular mycorrhizal fungal (AMF) strain may increase grain Zn concentration in bread wheat. For this purpose we performed a multifactorial pot experiment, in which the effects of two green manures (red clover, sunflower), ZnSO4 application, soil γ-irradiation (elimination of naturally occurring AMF), and AMF inoculation were tested.
View Article and Find Full Text PDFElevated contents of mercury (Hg) and nickel (Ni) in soils and foodstuffs can threaten human health. As contents of these metals in soil, water and food vary from place to place, the associated risks will also be different in various parts of a region and it should be considered for environmental decision making and human health management. The objective of this study was to map the variation of human health risks related to Ni and Hg in soil, water and foodstuffs across an entire region, in province of Hamedan western Iran as an example case.
View Article and Find Full Text PDFPhytoremediation is a promising technique for cleaning petroleum contaminated soils. In this study, the effects of two grass species (Festuca arundinacea Schreb. and Festuca pratensis Huds.
View Article and Find Full Text PDFSorption hysteresis in natural sorbents has important environmental implications for pollutant transport and bioavailability. We examined sorption reversibility of Cd(II) and Pb(II) on zeolite and bentonite. Sorption isotherms were derived by sorption of Cd(II) and Pb(II) from solutions containing a range of the metal concentrations corresponding to 10-100% maximum sorption capacity (SCmax) of the sorbents.
View Article and Find Full Text PDFEthylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and other synthetic polycarboxylic acids have been shown to possess substantial capacity as washing agents of heavy metal-polluted soils, but they are environmentally problematic. Therefore, a sample of natural soluble humic substances (HS) was tested as a possible substitute. The efficiency of HS to extract cadmium (Cd), copper (Cu), and lead (Pb) from a strongly polluted calcareous urban soil was compared with that of EDTA and NTA.
View Article and Find Full Text PDFWe performed a survey in central Iran to assess the variability in grain zinc (Zn), iron (Fe), and copper (Cu) concentrations of winter wheat and their relationships with soil and climate variables under field conditions. The goal was to identify factors that should be studied further to improve wheat cultivation in the study area with respect to the nutritional quality of this main Iranian staple crop. Soil and grain samples were collected from 137 randomly selected wheat fields in the provinces of Qom, Isfahan, and Fars.
View Article and Find Full Text PDFThe use of groundwater with high fluoride concentrations poses a health threat to millions of people around the world. This study aims at providing a global overview of potentially fluoride-rich groundwaters by modeling fluoride concentration. A large database of worldwide fluoride concentrations as well as available information on related environmental factors such as soil properties, geological settings, and climatic and topographical information on a global scale have all been used in the model.
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