Anwar A. Aly

Conocarpus biochar as a soil amendment for reducing heavy metal availability and uptake by maize plants.

The objective of this study was to assess the use of Concarpus biochar as a soil amendment for reducing heavy metal accessibility and uptake by maize plants (Zea mays L.). The impacts of biochar rates (0.0, 1.0, 3.0, and 5.0% w/w) and two soil moisture levels (75% and 100% of field capacity, FC) on immobilization and availability of Fe, Mn, Zn, Cd, Cu and Pb to maize plants as well as its application effects on soil pH, EC, bulk density, and moisture content were evaluated using heavy metal-contaminated soil collected from mining area. The biochar addition significantly decreased the bulk density and increased moisture content of soil. Applying biochar significantly reduced NH4OAc- or AB-DTPA-extractable heavy metal concentrations of soils, indicating metal immobilization. Conocarpus biochar increased shoot dry biomass of maize plants by 54.5–102% at 75% FC and 133–266% at 100% FC. Moreover, applying biochar significantly reduced shoot heavy metal concentrations in maize plants (except for Fe at 75% FC) in response to increasing application rates, with a highest decrease of 51.3% and 60.5% for Mn, 28% and 21.2% for Zn, 60% and 29.5% for Cu, 53.2% and 47.2% for Cd at soil moisture levels of 75% FC and 100% FC, respectively. The results suggest that biochar may be effectively used as a soil amendment for heavy metal immobilization and in reducing its phytotoxicity.

Olive mill wastewater treatment using a simple zeolite-based low-cost method

Olive mill wastewater (OMW), a liquid by-product of the olive oil industry, represents a severe environmental problem owing to its high pollution load. In this study, successive columns containing different types of natural materials were investigated for their OMW treatment efficiency. Passing OMW through three columns of gravel, fine sand, and a mixture of acidified cotton and zeolite (weight:weight ratio of cotton:clinoptilolite of 2:1), followed by treatment with activated charcoal (AC) and lime, was the best treatment in terms of the quality of water obtained. This treatment decreased concentrations of [Formula: see text] , B, K, P, and total fat in OMW by mean percentages of 78.0, 92.4, 66.6, 48.3, and 93.3%, respectively. Furthermore, it decreased OMW turbidity and electric conductivity (EC) by 96.8 and 48.4%, respectively. Most contaminants were removed from the OMW in the cotton/clinoptilolite column owing to the high sorption affinity of clinoptilolite on its active sites. The AC was efficient for organic particle removal; meanwhile, lime was used to raise the pH of the treated OMW (TOMW) from 2.9 to 5.1. This simple method enables us to obtain environmentally friendly TOMW that can be safely used for irrigation.

Hydrochemical characteristics of Egypt western desert oases groundwater

In this study, the distribution of the chemical constituents (major, minor, and trace elements) is determined in different localities in Egypt’s western desert oases, i.e., Bahariya, Farafra, Bahrean, Siwa, El-Gara, and Al-Jaghbub oases. The Nubian Sandstone Aquifer (NSA) is shared between all oases; however, the Limestone Aquifer (LA) is shared only between the western oases, i.e., Bahrean, Siwa, El-Gara, and Al-Jaghbub. The LA is usually located above NSA in Egypt’s western desert. The results indicate notable difference in chemical characteristics between the LA and the NSA waters. Under furrow surface irrigation systems that are commonly used in the Bahariya and Farafra oases, negligible potential for harmful effects on soils and plants is anticipated. However, in case of using drip or sprinkler irrigation systems, the iron and manganese identified in groundwater may precipitate, causing blockages to occur. The LA waters salinity is found to be higher than NSA and above acceptable level for irrigation. Besides, salinity, chloride, and water sodicity make this water unsuitable for irrigation. Durov and piper diagrams reveal that the majority of investigated waters were calcium–magnesium sulfate water type corresponding the Bahariya and Farafra, and sodium, chloride, and sulfate water type corresponding the Siwa, Bahrean, El-Gara, and Al-Jaghbub waters. The saturation indices for minerals indicated that most studied LA waters were undersaturated for halite; however, the NSA waters were saturated with respect to aragonite, calcite, and dolomite.

Contaminants and salinity removal of olive mill wastewater using zeolite nanoparticles

ABSTRACT Successive columns of gravel, fine sand, and mixture of acidified cotton and zeolite clinoptilolite nanoparticles (ZNP) were found efficient in olive mill waste water (OMW) treatment and desalination. The treatment decreased OMW’s salinity from 10.9 to 1.6 dSm−1 due to K+ removal. Furthermore, most total phenol contents were removed. The adsorption of K+ (aqueous solution) onto normal zeolite particles (NSP) and ZNP indicated that the pseudo-second order kinetic model is best model for K+ adsorption. Langmuir model was best fit model for K+ adsorption equilibrium. K+ maximum adsorption capacities were 7.2 and 16.5 mgg−1 for NSP and ZNP, respectively.

Salinity Stress Promote Drought Tolerance of Chenopodium Quinoa Willd

ABSTRACT A greenhouse experiment was conducted to investigate the impact of water and salt stress in Quinoa plants (Chenopodium quinoa Willd.). Irrigation treatments using saline solutions of 0 (control), 50(T1), 200(T2), 400(T3), 600(T4), and 800(T5) mM sodium chloride (NaCl) were adopted. The results indicated that quinoa plants can tolerate water stress (50%FC) when irrigated with moderately saline water (T1 and T2, respectively). Salinity stress increases quinoa drought tolerance in terms of biomass production. Neither osmotic stress nor ions deficiency/toxicity seems to be determinant under T1 and 100%FC. Salinity induced a significant increase of sodium (Na+) and chloride (Cl−), while reduced magnesium (Mg2+) and calcium (Ca2+) in stems, leaves, seed’s coating, and seeds. The potassium (K+)/Na+ ratio never fell below 1 with T1; yet, fell to 0.78 and 0.89 with T2 for 100% and 50%FC, respectively. The seed coat limited the passage of possibly toxic concentrations of Na+ and Cl− to seed interior, as high Na+ and Cl− was found in the seed coat.