Mora Abrahan, Jumbo-Flores Diana, González-Merizalde Max, Bermeo-Flores Santos A, Alvarez-Figueroa Pablo, Mahlknecht Jürgen, Hernández-Antonio Arturo
Escuela de Ingeniería y Ciencias. Tecnológico de Monterrey, Av. Eugenio Garza Sada Sur 2501, CP 64849, Monterrey, Nuevo León, Mexico.
Universidad Nacional de Loja, Provincia de Loja, La Argelia, Loja, Ecuador.
Bull Environ Contam Toxicol. 2019 Feb;102(2):210-217. doi: 10.1007/s00128-019-02545-w. Epub 2019 Jan 18.
Artisanal and small-scale gold mining (ASGM) has been performed in the southern Ecuadorian Amazon since the colonial period. However, its effects on fluvial systems have been poorly investigated. Thus, in order to calculate the normalized enrichment factors (NEF) of several heavy metals in fluvial sediments of the Zamora River basin (Ecuadorian Amazon), we analyzed bottom sediments along ASGM-affected and unaffected river sections. The results indicated that sediments of the Congüime River have NEF between 2.2 and 2.3 for Cu (moderate contamination) and higher than 3 for Mn, Zn, Pb, and Hg (severe contamination). Similarly, a severe contamination is also observed in the lower Nangaritza River, due to sediments of this sector have NEF > 3 for Zn, Pb, and Hg. Bottom sediments from the Nambija and Zamora rivers showed a severe contamination with Hg (NEF > 3), suggesting the existence of ASGM activities in the upper Zamora River basin.
自殖民时期以来，厄瓜多尔亚马逊地区南部就一直在进行手工和小规模金矿开采（ASGM）。然而，其对河流系统的影响却鲜有研究。因此，为了计算萨莫拉河流域（厄瓜多尔亚马逊地区）河流沉积物中几种重金属的归一化富集因子（NEF），我们分析了受ASGM影响和未受影响的河段的底部沉积物。结果表明，孔圭梅河沉积物中铜的NEF在2.2至2.3之间（中度污染），而锰、锌、铅和汞的NEF高于3（重度污染）。同样，在楠加里察河下游也观察到重度污染，因为该河段沉积物中锌、铅和汞的NEF > 3。南比哈河和萨莫拉河的底部沉积物显示出汞的重度污染（NEF > 3），这表明萨莫拉河流域上游存在ASGM活动。
