Dick, Grasiele creator Schumacher, Mauro Valdir creator text periodical abstract or summary bl. continuing eng ABSTRACT Rainfall is one of the primary nutrient inputs to vegetation and its chemical composition is dependent on air quality as falling rain scavenges gaseous and particulate emissions from natural, industrial, and agricultural activities. The objective of this study was to evaluate whether the vegetation burn in a region of the Pampa biome influences the pH and chemical composition (anions) in incident rainfall. Nitrate, sulfate, and chloride concentrations, as well as the pH of the rainwater, were influenced by suspended particles in the atmosphere from biomass burning of native grassland and pasture renewal. The rainwater was acidified by, ash, and soot, which introduced large amounts of chloride and sulfate into the ecosystems caused by burning vegetation. Keywords: rainwater acidification, anions, atmospheric pollution. Publicação on-line; 20 ref.; 2 tables; 4 illus.; Summary (En) CHUVA ÁCIDA POLUIÇÃO DO AR ÂNION Rio de Janeiro-RJ Instituto de Florestas - UFRRJ 1994 2025-0451 1415-0980 / ISSN 2179-8087 0nline BR2026000286 v. 26(3) p. 1-6; (2019) https://www.scielo.br/j/floram/a/gfWLhZ97GLLTMfHJJQk7fMG/?format=pdf&lang=en https://www.scielo.br/j/floram/a/gfWLhZ97GLLTMfHJJQk7fMG/?format=pdf&lang=en BR-BrBNA 260407 20260407045455.0 eng