Activated ZnCl2 biochar and humic acid as additives in monoammonium phosphate fertilizer: Physicochemical characterization and agronomic effectiveness.

Activated zinc biochar (ZnBC) and humic acid (HA) were used as coating agents in a soluble monoammonium phosphate (MAP) to modify phosphorus (P) use efficiency by altering adsorption/desorption kinetics between the granule region and the soil. The coated treatments MAPZnBC and MAPHA were compared with MAP through P diffusivity, kinetics, and agronomic evaluation. Eucalyptus sawdust was used as biomass for biochar synthesis, and a pre-pyrolysis treatment with zinc chloride (ZnCl) was applied.

Algal biomass from wastewater: soil phosphorus bioavailability and plants productivity.

The cultivation of microalgae in wastewater allows to obtain a biomass concentrated in nutrients and organic material. This biomass added to phosphate fertilizers can promote a slow release of the nutrient and consequently a higher absorption of phosphorus (P). The objective of this study was to investigate P uptake by plants subjected to triple superphosphate (TSP) fertilization, added with microalgae biomass (MB) grown in wastewater.

Agronomic efficiency of phosphate fertilizers produced by the re-use of a metallurgical acid residue.

The production of fertilizers with industrial wastes reduces the environmental impacts of waste disposal and improves environmental sustainability by generating added-value products. Our objective with this study was to evaluate the agronomic performance and potential soil/plant contamination with heavy metals of alternative phosphate (P) fertilizers, obtained from the acidulation of phosphate rocks (PR) by a metallurgical acidic waste. Seven P fertilizers were evaluated: three PR (Araxá, Patos, and Bayóvar), their respective acidulated products (PAPR), and triple superphosphate fertilizer (TSP).

Nitrogen release from urea with different coatings.

Background: Coatings or urease inhibitors are designed to reduce losses of ammonia [NH ] from urea fertilizers. However, nitrogen (N) release and its effects on soil solution have not previously been evaluated under standardized conditions in soils. In this study, the urea fertilizers were incubated in chambers filled with sandy loam soil, adapted for the collection of NH and soil solution by centrifugation.

Sulfur and Zinc Availability from Co-granulated Zn-Enriched Elemental Sulfur Fertilizers.

Acidification by oxidation of elemental sulfur (ES) can solubilize ZnO, providing slow release of both sulfur (S) and zinc (Zn) in soil. For this study, a new granular fertilizer with ES and ZnO was produced and evaluated. The effect of incorporating microorganisms or a carbon source in the granule was also evaluated.

Increasing Soluble Phosphate Species by Treatment of Phosphate Rocks with Acidic Waste.

The development of efficient fertilizers with a diminished environmental footprint will help meet the increasing demand for food and nutrients by a growing global population. Our objective was to evaluate whether an acidic mine waste (AMW) could be used beneficially by reacting it with sparingly soluble phosphate rocks (PRs) to produce more soluble P fertilizer materials. Three PRs from Brazil and Peru were reacted with different concentrations of AMW.

Soluble phosphate fertilizer production using acid effluent from metallurgical industry.

Preventive and effective waste management requires cleaner production strategies and technologies for recycling and reuse. Metallurgical industries produce a great amount of acid effluent that must be discarded in a responsible manner, protecting the environment. The focus of this study was to examine the use of this effluent to increase reactivity of some phosphate rocks, thus enabling soluble phosphate fertilizer production.

Zinc deficiency affects physiological and anatomical characteristics in maize leaves.

Zinc (Zn) is an essential microelement involved in several plant physiological processes. Therefore, it is important to identify Zn deficiencies promptly--before extensive damage occurs to the plant. The diagnostic tools that are used to identify Zn deficiencies are very important in areas where Zn deficiencies occur.