Geochemical fractions and phytoavailability of Zinc in a contaminated calcareous soil affected by biotic and abiotic amendments

Abstract

Many studies have conducted to determine the best management practice to reduce the mobility and phytoavailability of the trace metals in contaminated soils. In this study, geochemical speciation and phytoavailability of Zn for sunflower were studied after application of nanoparticles (SiO and zeolite, with an application rate of 200 mg kg) and bacteria [Bacillus safensis FO-036b(T) and Pseudomonas fluorescens p.f.169] to a calcareous heavily contaminated soil. Results showed that the biotic and abiotic treatments significantly reduced the Zn concentration in the aboveground to non-toxicity levels compared to the control treatment, and the nanoparticle treatments were more effective than the bacteria and control treatments. The concentration of CaCl-extractable Zn in the treated soils was significantly lower than those of the control treatment. The results of sequential extraction showed that the maximum portion of total Zn belonged to the fraction associated with iron and manganese oxides. On the contrary, the minimum percent belonged to the exchangeable and water-soluble Zn (F). From the environmental point of view, the fraction associated with iron and manganese oxides is less bioavailable than the F and carbonated fractions. On the basis of plant growth promotion, simultaneous application of the biotic and abiotic treatments significantly increased the aboveground dry biomass yield and also significantly reduced the CaCl-extractable form, uptake by aboveground and translocation factor of Zn compared to the control treatment. Therefore, it might be suggested as an efficient strategy to promote the plant growth and reduce the mobile and available forms of toxic metals in calcareous heavily contaminated soils.

Morpho-physiological and biochemical response of wheat to various treatments of silicon nano-particles under drought stress conditions

“…Sedghi et al 20 stated that the utilization of silicon nanoparticles is assuming a significant part in the plant resistance against the shortage of water over expanding amino acids, chlorophyll b contents, lipids, and proteins. Among other NPs, the Si-NPs are helpful in elevation the plant growth and photosynthesis under an intensive atmosphere 21 , 22 .…”

Lead Bioavailability in the Environment: Its Exposure and and Effects

“…Other sources are the manufacturing of batteries, coal burning, typecasting, and older houses and buildings. Mining and smelting activities are the other major exposure pathways of lead's entrance into the environment [1,11]. Farming practices, for example, spraying of pesticide and organic fertilizers as well as soil irrigation with wastewater, are also pathways for Pb release to the soil and water [12][13][14].…”

Integrated Soil Fertility Management in Fruit Crops: An Overview

“…The conducted researches in Iran have shown the positive effects of the simultaneous application of biological and chemical fertilizers on increasing the yield and decreasing the use of chemical fertilizers application (Amirabadi et al, 2010;Hassanabadi et al, 2012). Also, integrated application of biological and chemical fertilizers has reduced the environmental stress such as drought (Naseri et al, 2017), soil salinity (Daei et al, 2009), and soil compaction (Miransari et al, 2008) and soil contamination with toxic metals (Mousavi et al, 2018a(Mousavi et al, , 2017b(Mousavi et al, , 2018b. Mycorrhizal inoculants are the most widely used and known microbial inoculum used in different fruit crops of Iran (Table 10).…”