Aquatic ecosystems in the Amazon are exposed to mercury, mostly from natural sources. Hg accumulation in fish tissues poses a risk to the local population since fish is one of the main sources of protein in the region. The aim of this study was to evaluate Hg distribution in demersal and pelagic carnivorous fish between seasons in Puruzinho Lake in the Brazilian Amazon. Total Hg was quantified in 221 individuals of 8 species obtained during the high water and low water seasons. Two-way ANOVA indicated an interaction between foraging habitat and season. During high water, total Hg concentrations were similar between demersal and pelagic fish, while in low water, total Hg levels were higher in demersal fish. Pelagic and demersal fishes' Hg levels were similar between the two seasons.

中文翻译：

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来自巴西亚马逊普鲁兹尼奥湖的深海鱼类和远洋鱼类之间的汞积累变化。

亚马逊河的水生生态系统暴露于汞，其中大部分来自自然资源。鱼体内汞的积累对当地居民构成了威胁，因为鱼是该地区主要的蛋白质来源之一。这项研究的目的是评估巴西亚马逊河普鲁济尼奥湖不同季节的海底和中层肉食性鱼类中汞的分布。在高水位和低水位季节期间，对8种物种的221个人进行了总汞定量。双向方差分析表明觅食生境和季节之间存在相互作用。在高水位时，海底鱼类和远洋鱼类的总Hg浓度相似，而在低水位时，海底鱼类的总Hg水平较高。在两个季节之间，上层鱼类和深海鱼类的汞含量相似。