title: Effects of sewage sludge fertilizer on heavy metal accumulation and consequent responses of sunflower (Helianthus annuus).
abstract: Use of sewage sludge, a biological residue produced from sewage treatment processes in agriculture, is an alternative disposal technique of waste. To study the usefulness of sewage sludge amendment for Helianthus annuus, a pot experiment was conducted by mixing sewage sludge at 2.5, 5, and 7.5 % (w/w) amendment ratios to the agricultural soil. Soil pH decreased whereas electrical conductivity, organic matter, total N, available P, and exchangeable Na, K, and Ca increased in soil amended with sewage sludge in comparison to unamended soil. Sewage sludge amendment led to significant increase in Pb, Ni, Cu, Cr, and Zn concentrations of soil. The increased concentration of heavy metals in soil due to sewage sludge amendment led to increases in shoot and root concentrations of Cr, Cu, Ni, and Zn in plant as compared to those grown on unamended soil. Accumulation was more in roots than shoots for most of the heavy metals. Moreover, high metal removal for the harvestable parts of the crops was recorded. Sewage sludge amendment increased root and shoot length, leaves number, biomass, and antioxidant activities of sunflower. Significant increases in the activities of antioxidant enzymes and in the glutathione, proline, and soluble sugar content in response to amendment with sewage sludge may be defense mechanisms induced in response to heavy metal stress. Graphical abstract Origin, fate and behavior of sewage sludge fertilizer.
authors.affiliation: ENIS. Laboratory of Water-Energy-Environment, University of Sfax-Tunisia, Street Soukra Km 3.5. BP 1173, 3038, Sfax, Tunisia. dalel_belhaj@yahoo.fr.
authors.forename: Dalel
authors.initials: D
authors.lastname: Belhaj
authors.affiliation: ENIS. Laboratory of Water-Energy-Environment, University of Sfax-Tunisia, Street Soukra Km 3.5. BP 1173, 3038, Sfax, Tunisia.
authors.forename: Nada
authors.initials: N
authors.lastname: Elloumi
authors.affiliation: ENIS. Laboratory of Water-Energy-Environment, University of Sfax-Tunisia, Street Soukra Km 3.5. BP 1173, 3038, Sfax, Tunisia.
authors.forename: Bouthaina
authors.initials: B
authors.lastname: Jerbi
authors.affiliation: Faculty of Pharmacy, Laboratory of Botany and Cryptogamy, University of Limoges, GRESE EA 4330, 2 rue du Docteur Marcland, 87025, Limoges, France.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Zouari
authors.affiliation: Department of Life Sciences, University of Sfax-Tunisia, FSS, Street Soukra Km 3.5, Sfax, Tunisia.
authors.forename: Ferjani Ben
authors.initials: FB
authors.lastname: Abdallah
authors.affiliation: Department of Life Sciences, Laboratory of Biodiversity and Aquatic Ecosystems, Ecology and Planktonology, University of Sfax-Tunisia, FSS, Street Soukra Km 3.5, BP 1171, 3000, Sfax, Tunisia.
authors.forename: Habib
authors.initials: H
authors.lastname: Ayadi
authors.affiliation: ENIS. Laboratory of Water-Energy-Environment, University of Sfax-Tunisia, Street Soukra Km 3.5. BP 1173, 3038, Sfax, Tunisia.
authors.forename: Monem
authors.initials: M
authors.lastname: Kallel
mesh_terms: D000383:Agriculture; D018533:Biomass; D005308:Fertilizers / Q000032:analysis*; D006368:Helianthus / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D019216:Metals, Heavy / Q000032:analysis* / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism; D014416:Tunisia
chemical_list: D005308:Fertilizers; D019216:Metals, Heavy; D012722:Sewage; D012987:Soil; D012989:Soil Pollutants
keywords: Metal accumulation; Oxidative stress; Sewage sludge amendments; Sunflower