Adsorção de fósforo por solo tratado do semiárido brasileiro

Abstract

Eutrophication is a major cause of deterioration of aquatic ecosystems worldwide and occurs when nutrients, nitrogen and phosphorus improve, leading to overgrowth of algae, especially cyanobacteria, which can release toxins and cause imbalance in biota and on physicochemical properties of water. This continuous nutrient resource, whether from point or diffuse sources, on aquatic systems results in increased phosphorus on sediment, which can lead to internal fertilization, which is an internal and relevant source. To mitigate this problem, restoration techniques such as the application of geo-engineering (manipulation of the biogeochemical cycle of the phosphorus) using natural or modified adsorbents for phosphorus adsorption molecules can be applied. Thus, the objective of this work was to evaluate the application of geoengineering techniques when using a natural soil of the Brazilian tropical semiarid (Planosol/Afisols) with simple modification by acidification with the intention of enhancing its adsorption at low cost at low cost. For data analysis we used the Langmuir isotherm model and it showed that for the soil in question the acid soil was not satisfactory. This is probably due to the mineralogical composition of the soil that has some low zero-charge point (PCZ) minerals and insufficient pH-dependent fillers to meet the treatment and was therefore not responsive to adsorption. This work was important to show the unfeasibility of this methodology in low PCZ soils, bringing new findings and direction to new work and new approaches that help bridge the low cost geoengineering gap.