NO2 - and NO3 - leaching and solubilization of Al in variable charge soils treated with sewage sludge

The use of sewage sludge (SS) for agricultural purposes provides macronutrients and micronutrients and increases the soil organic matter. This study was conducted after 5 years of agricultural sludge application to a variable charge soil (clay loam-textured dark red dystroferric oxisol) in an experimental field at the Brazilian Federal Agriculture Research Institute in JaguariA(0)na, So Paulo. The mineralization of SS organic matter forms sulfate (SO4 (2-)) and ammonium (NH4 (+)) or ammonia (NH3). Subsequently, nitrification of NH4 (+) or NH3 occurs, resulting in the formation of nitrite (NO2 (-)) and NO3 (-) which release H+ and increases the redox potential of the solution. In studied area, the SS organic matter decomposition favored the anion exclusion, which led to SO4 (2-), NO2 (-) and NO3 (-) leaching along the profile. At 2 m, the soil solution showed pH and Eh values of 4.2 and 600 mV, respectively. In addition, the highest soil NO2 (-) (27 mg/L), NO3 (-) (1220 mg/L) and Al (20 mg/L) concentrations were observed at 2 m. The low pH and high Eh at 2 m potentially resulted from the oxidation of leached NO2 (-). Furthermore, the H+ released in solution due to nitrification was partially consumed during the solubilization of soil Al compounds, such as kaolinite and amorphous Al oxide. Geochemical modeling (GM) indicated that Al3+ in solution results from the solubilization of kaolinite and amorphous Al oxide. GM also highlights the importance of soil oxide protonation in buffering the soil solution acidity and in controlling the solubility of Al compounds and free Al in solution.The use of sewage sludge (SS) for agricultural purposes provides macronutrients and micronutrients and increases the soil organic matter. This study was conducted after 5 years of agricultural sludge application to a variable charge soil (clay loam-textured dark red dystroferric oxisol) in an experimental field at the Brazilian Federal Agriculture Research Institute in JaguariA(0)na, So Paulo. The mineralization of SS organic matter forms sulfate (SO4 (2-)) and ammonium (NH4 (+)) or ammonia (NH3). Subsequently, nitrification of NH4 (+) or NH3 occurs, resulting in the formation of nitrite (NO2 (-)) and NO3 (-) which release H+ and increases the redox potential of the solution. In studied area, the SS organic matter decomposition favored the anion exclusion, which led to SO4 (2-), NO2 (-) and NO3 (-) leaching along the profile. At 2 m, the soil solution showed pH and Eh values of 4.2 and 600 mV, respectively. In addition, the highest soil NO2 (-) (27 mg/L), NO3 (-) (1220 mg/L) and Al (20 mg/L) concentrations were observed at 2 m. The low pH and high Eh at 2 m potentially resulted from the oxidation of leached NO2 (-). Furthermore, the H+ released in solution due to nitrification was partially consumed during the solubilization of soil Al compounds, such as kaolinite and amorphous Al oxide. Geochemical modeling (GM) indicated that Al3+ in solution results from the solubilization of kaolinite and amorphous Al oxide. GM also highlights the importance of soil oxide protonation in buffering the soil solution acidity and in controlling the solubility of Al compounds and free Al in solution74646254638FAPESP [02/09667-3, 02/12671-2, 03/10949-6

Bio-Inspired Systems in Nonsurgical Periodontal Therapy to Reduce Contaminated Aerosol during COVID-19: A Comprehensive and Bibliometric Review

Background: On 30 January 2020, a public health emergency of international concern was declared as a result of the new COVID-19 disease, caused by the SARS-CoV-2 virus. This virus is transmitted by air and, therefore, clinical practices with the production of contaminant aerosols are highly at risk. The purpose of this review was to assess the effectiveness of bio-inspired systems, as adjuvants to nonsurgical periodontal therapy, in order to formulate bio-inspired protocols aimed at restoring optimal condition, reducing bacteremia and aerosols generation. Methods: A comprehensive and bibliometric review of articles published in English. Research of clinical trials (RCTs) were included with participants with chronic or aggressive periodontal disease, that have compared benefits for nonsurgical periodontal therapy (NSPT). Results: Seventy-four articles have been included. For probing depth (PPD) there was a statically significant improvement in laser, probiotic, chlorhexidine groups, such as gain in clinical attachment level (CAL). Bleeding on probing (BOP) reduction was statistically significant only for probiotic and chlorhexidine groups. There were changes in microbiological and immunological parameters. Conclusions: The use of bio-inspired systems in nonsurgical periodontal treatment may be useful in reducing risk of bacteremia and aerosol generation, improving clinical, microbiological and immunological parameters, of fundamental importance in a context of global pandemic, where the reduction of bacterial load in aerosols becomes a pivotal point of clinical practice, but other clinical trials are necessary to achieve statistical validity

Ion leaching and soil solution acidification in a vadose zone under soil treated with sewage sludge for agriculture

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOIn this study, we performed monitoring of the soil solution (SS) over 10 years on a loamy/clayey-textured Dark Red Dystroferric Oxisol that received sewage sludge for agricultural purposes. The SS was obtained by lysimeters installed along the walls of a1928189FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO02/09667-3,02/12671-2, 03/10949-6, 11/19106-8,152112/2005-