Soil Application of Selenium in Wheat ( L.) Under Water Stress Improves Grain Quality and Reduces Production Losses.

Selenium (Se) is an essential element for humans. However, much of the world's human population is deficient in this element, which has become a public health problem. This study aimed to evaluate whether applying severe water stress to wheat plants ( L.

Spatial distribution of Pb and Zn in soils under native vegetation in Southeast Brazil.

Heavy metals can play an important biological role as micronutrients but also as potentially toxic elements (PTEs). Understanding the natural concentrations of PTEs-Pb and Zn included-in soils allows for the identification and monitoring of contaminated areas and their role in environmental risk assessment. In this study, we aim to determine semi-total or natural and available concentrations of Pb and Zn in topsoils (0-20 cm depth) from 337 samples under native vegetation in the State of Minas Gerais, Brazil.

Rare earth elements (REEs): geochemical patterns and contamination aspects in Brazilian benchmark soils.

Rare earth elements have been increasingly used in modern societies and soils are likely to be the final destination of several REE-containing (by)products. This study reports REE contents for topsoils (0-20 cm) of 175 locations in reference (n = 68) and cultivated (n = 107) areas in Brazil. Benchmark soil samples were selected accomplishing a variety of environmental conditions, aiming to: i) establishing natural background and anthropogenic concentrations for REE in soils; ii) assessing potential contamination of soils - via application of phosphate fertilizers - with REE; and, iii) predicting soil-REE contents using biomes, soil type, parent material, land use, sand content, and biomes-land use interaction as forecaster variables through generalized least squares multiple regression.

Modeling arsenic content in Brazilian soils: What is relevant?

Arsenic accumulation in the environment poses ecological and human health risks. A greater knowledge about soil total As content variability and its main drivers is strategic for maintaining soil security, helping public policies and environmental surveys. Considering the poor history of As studies in Brazil at the country's geographical scale, this work aimed to generate predictive models of topsoil As content using machine learning (ML) algorithms based on several environmental covariables representing soil forming factors, ranking their importance as explanatory covariables and for feeding group analysis.

Ecological risk assessment of cerium for tropical agroecosystems.

Cerium (Ce) is present in high technology materials and in mineral P fertilizers and the use and discharge of such resources may change the natural status of Ce in the soil environment. Brazilian soils in farming areas are significantly exposed to increased levels of unintentionally-added Ce through intensive input of phosphate fertilizers. The aims of this study were to evaluate the ecotoxicological risk to plants growing in tropical soils contaminated with Ce, as well as to create a database to support future legislation regulating the limits of this element in Brazilian and conceivably other tropical soils.