Impacts of fertilization on metal(loid) transfer from soil to wheat in a long-term fertilization experiment – using 87Sr/86Sr isotopes as metal(loid) tracer
Year: 2025
Type: article
Abstract: • Mineral, organic and combined fertilization in long-term field trial were studied. • Mineral fertilization raised the most toxic metalloid concentrations in wheat grain. • Micronutrient Zn in wheat grain increased only with mineral + organic fertilization • The 87 Sr/ 86 Sr ratio of wheat grain are indicative of the fertilization treatment. Fertilizers are widely used to sustain food production but can alter soil chemistry and potentially contribute toxic metal(loid)s to agricultural systems. For the first time, this study examined the occurrence of select metal(loid)s (Zn, Sr, V, As, Cd, Pb, and U) alongside the 87 Sr/ 86 Sr isotope ratio in agricultural soil— both total and mobile pools— and wheat grain. Samples were collected from one of four fertilization treatments— mineral (NPK), organic (manure), combined mineral + organic, and unfertilized controls— within the 120-year Static Fertilization Experiment in Bad Lauchstädt, Germany. Fertilization treatments altered soil pH and organic carbon resulting in mineral fertilization lowering pH and increasing cation mobility (Cd, Zn, Sr), whereas organic fertilization increased pH and enhanced the mobility of non-cationic elements (V, As). These effects translated into higher Cd in mineral-fertilized wheat grain and higher As in mineral + organic wheat grain. Fertilization shifted the 87 Sr/ 86 Sr ratios in soils and wheat grains toward that of the applied fertilizers, with mineral and mineral + organic wheat grains inheriting the triple super phosphate signature (0.70778) and organic wheat grains matching manure (0.70883). The 87 Sr/ 86 Sr ratio in the mobile soil pool was correlated with mobile As, V, and P, demonstrating that the 87 Sr/ 86 Sr ratio reflects both fertilizer source and the mobility of select co-occurring metal(loid)s. Overall, this study demonstrates metal(loid) enrichment in soil and wheat from fertilization and establishes 87 Sr/ 86 Sr ratio as a robust tracer of fertilizer impacts. These findings underscore the need for targeted fertilization strategies to reduce contaminant accumulation in agroecosystems.
Source: Environment International
Authors: Robert C. Hill, Aleksandra Pieńkowska, Ines Merbach, Thomas Reitz, E.Marie Muehe, Avner Vengosh
Language: English
Topic: Heavy metals in environment
Subfield: Pollution
Field: Environmental Science
Domain: Physical Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $4,750
OpenAlex ID: W4414997470