Estuaries offer favorable conditions for human settlement. As a result, pollutants, such as metals, have been released to these systems. Those are adsorbed by particulate material that tend to settle at the bottom and sink in the sediment. This article analyses the results of metals in sediments of the Sado estuary (Portugal) on a large spatial scale, to differentiate areas according to their impacts and possible sources. The metals were analyzed by Atomic Absorption Spectroscopy and a Direct Mercury Analyser. Higher concentrations, particularly of As, Cr and Zn ([32, 40] mg/kg, [102, 115] mg/kg, [672, 896] mg/kg) were observed at upstream areas of the Alcácer and Marateca channels. Both anthropogenic and natural origins in the area were considered to understand the results, such as industrial activities and geological context. Overall, the concentrations registered do not reach levels of contamination, and the improvement in the quality of the estuary is reflected.

中文翻译：

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大西洋中外层河口沉积物中金属的空间变化（葡萄牙萨多河口）


河口为人类居住提供了有利条件。结果，金属等污染物已被释放到这些系统中。这些被颗粒材料吸附，这些颗粒材料往往会沉淀在底部并沉入沉积物中。本文在大空间尺度上分析了萨多河口（葡萄牙）沉积物中金属的结果，以根据其影响和可能的来源来区分区域。金属通过原子吸收光谱法和直接汞分析仪进行分析。在 Alcácer 和 Marateca 通道的上游区域观察到较高的浓度，特别是 As、Cr 和 Zn（[32， 40] mg/kg、[102， 115] mg/kg、[672， 896] mg/kg）。该地区的人为和自然起源都被考虑在内，以理解结果，例如工业活动和地质背景。总体而言，记录的浓度没有达到污染水平，反映了河口质量的改善。