ABSTRACT Most of South America lacks studies on rainwater composition. The present study evaluates rainwater composition and bulk deposition inside Barcarena power station, located at the mouth of the Tocantins River with Amazon River in Brazil. In 2012, 24-h rainwater samples were collected inside the ELETRONORTE power plant (n = 93), and pH, EC, cations and anions were analyzed. In order of abundance, the rainwater ions were Na+ > Cl− > SO4−2 > Ca+2 > K+ > F− > Mg+2 > NH4+-N > NO3−-N. pH values ranged from 4.5 to 6.9, with 17 events with pH <5.6 and 5 events with pH < 5.0. Sodium and Cl− were the dominant ions with sea salt as main contribution. Acidity, enrichment factors and principal component analysis (PCA) indicate that F−, SO4−2 and NO3−-N in the rainwater came from anthropogenic sources. Fluoride correlated strongly (>0.85) with Ca+2 and Mg+2, likely originated from same source in the aluminum production chain. Potassium originated from a mixture of anthropogenic and natural sources, with a good correlation (>0.70) with NO3−-N and NH4+-N, indicating biomass burning and fertilizer origins. In 2012, Barcarena total bulk deposition ranged from 14,070 to 17,890 mg m−2 y−1 with significant contributions of SO4−2 (2,385 to 2,851 mg m−2 y−1), F− (419 to 479 mg m−2 y−1) and NO3−-N (128 to 280 mg m−2 y−1). EC values (4 to 254 µS cm−1) indicated a medium site pollution severity (> 175 µS cm−1), which increased the risk of damage to electrical components. Highlights Chemical characterization of Barcarena, PA/Brazil rainwater in 2012 events. Apportionment sources of ionic rainwater content evaluated by acidity fraction, enrichment factors and principal component analysis. Anthropic fluoride, sulfate and nitrate local deposition values were compared with other regional data. Maintenance procedure recommendations under identified atmospheric deposition. GRAPHICAL ABSTRACT

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托坎廷斯河口巴卡雷纳电站内的雨水地球化学

摘要 南美洲大部分地区缺乏对雨水成分的研究。本研究评估了位于巴西亚马逊河和托坎廷斯河口的巴卡雷纳发电站内的雨水成分和大量沉积物。2012 年，在 ELETRONORTE 电厂（n = 93）内收集了 24 小时雨水样本，并分析了 pH、EC、阳离子和阴离子。雨水离子丰度为Na+>Cl->SO4-2>Ca+2>K+>F->Mg+2>NH4+-N>NO3--N。pH 值范围为 4.5 至 6.9，其中 17 个事件的 pH <5.6 和 5 个事件的 pH < 5.0。钠离子和氯离子是主要离子，海盐是主要贡献离子。酸度、富集因子和主成分分析 (PCA) 表明雨水中的 F-、SO4-2 和 NO3--N 来自人为来源。氟化物与 Ca+2 和 Mg+2 密切相关 (>0.85)，可能来自铝生产链中的同一来源。钾来源于人为和天然来源的混合物，与 NO3--N 和 NH4+-N 具有良好的相关性 (>0.70)，表明生物质燃烧和肥料来源。2012 年，Barcarena 的总堆积量为 14,070 至 17,890 mg m-2 y-1，其中 SO4-2（2,385 至 2,851 mg m-2 y-1）、F-（419 至 479 mg m-2 y）贡献显着-1) 和 NO3--N（128 至 280 mg m-2 y-1）。EC 值（4 到 254 µS cm-1）表明场地污染严重程度中等（> 175 µS cm-1），这增加了电气元件损坏的风险。亮点 2012 年事件中宾夕法尼亚州巴卡雷纳/巴西雨水的化学特征。以酸度分数评价离子雨水含量的分配来源，富集因子和主成分分析。人为氟化物、硫酸盐和硝酸盐局部沉积值与其他区域数据进行了比较。已确定的大气沉积下的维护程序建议。图形概要