Abstract

This study addresses the different biogeochemical parameters that control the dynamics of Hg, which is a less-studied metal in the Ebrié Lagoon. During two hydrological seasons, the dry season and the rainy season, we regularly sampled and analysed various compartments (e.g. sediments and fishes (Tilapia sp.)) of the lagoon. Thus, the physicochemical parameters were measured in situ (e.g. temperature, pH, salinity, redox potential and dissolved oxygen, total dissolved organic carbon, nitrates and sulphates), and the microbiological parameters (e.g. cultivable cells, total enzymatic activity and catabolic activity) were measured to establish the seasonal variations in the links between Hg and biogeochemical parameters through multivariate statistical analyses. The bioavailability of Hg from an unpolluted site was studied by comparing the ratios of fish and sediment. The results indicated that the seasons influenced the different biogeochemical factors, although for some factors, the variations were not significant. This influence was more pronounced in the dry season than in the rainy season. The impact of microbial activities and organic matter on Hg dynamics was observed in all seasons. However, other factors, such as pH, temperature, salinity, Eh and sulphates, influenced the dynamics of Hg only in the dry season.

中文翻译：

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埃布里亚泻湖（科特迪瓦）生态系统中汞动态的季节性：生物地球化学因素的影响。

摘要

这项研究解决了控制汞动力学的不同生物地球化学参数，汞是埃布里泻湖中研究较少的金属。在两个水文季节，干旱季节和雨季，我们定期采样和分析各种隔室（例如沉积物和鱼类（罗非鱼）sp。））。因此，就地测量了理化参数（例如温度，pH，盐度，氧化还原电势和溶解氧，总溶解有机碳，硝酸盐和硫酸盐），微生物参数（例如可培养细胞，总酶活性和分解代谢活性）为通过多变量统计分析测量汞和生物地球化学参数之间联系的季节性变化。通过比较鱼类和沉积物的比例，研究了无污染场所汞的生物利用度。结果表明，季节影响了不同的生物地球化学因素，尽管对于某些因素而言，变化并不显着。这种影响在旱季比雨季更为明显。在所有季节都观察到了微生物活动和有机物对汞动力学的影响。但是，其他因素（例如pH，温度，盐度，Eh和硫酸盐）仅在干燥季节影响Hg的动态。