Baptista Mafalda S, Vasconcelos Vitor M, Vasconcelos M Teresa S D
CIMAR/CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas, 289, 4050-123, Porto, Portugal,
Microb Ecol. 2014 Nov;68(4):671-8. doi: 10.1007/s00248-014-0454-x. Epub 2014 Jul 10.
In situ interactions between cyanobacteria and metals were studied at Torrão reservoir (Tâmega River, North Portugal). The metal content of water and sediments from the reservoir was monitored monthly at Marco de Canaveses (seasonally subjected to toxic blooms of Microcystis aeruginosa) and upstream at Amarante (no blooms recorded), for 16 months. During the 16 months of the study period, M. aeruginosa bloomed twice at Marco de Canaveses, firstly forming a scum, and later with colonies scattered throughout the reservoir. Metals Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were analysed in the sediment and in the water column. Cu-binding ligands in water were also determined. When no blooms were taking place, average metal levels for water and sediment were not statistically different at both locations. Therefore, it was considered that the absence of cyanobacteria blooms at Amarante was not due to differences in metal content. When blooms were taking place at Marco de Canaveses, a significant increase of metal levels in the sediment occurred simultaneously. Sediment quality guidelines showed that during this period, Cu and Pb concentrations (32.3 and 43.2 mg kg(-1), respectively) were potentially toxic. However, quantification of the exchangeable metal fraction indicated that these metals were probably not bioavailable. Concentration of Cu-binding ligands in water was higher during the blooms, indicating that cyanobacteria are capable of changing the metal speciation in situ in a reservoir.
在托朗水库（葡萄牙北部塔梅加河）研究了蓝藻与金属之间的原位相互作用。在16个月的时间里，每月对位于马尔科 - 德卡纳韦塞斯（季节性遭受铜绿微囊藻有毒水华）的水库水和沉积物以及上游阿马兰特（未记录到水华）的金属含量进行监测。在研究期间的16个月里，铜绿微囊藻在马尔科 - 德卡纳韦塞斯出现了两次水华，先是形成浮沫，后来菌落散布在整个水库。对沉积物和水柱中的镉、钴、铬、铜、铁、锰、镍、铅和锌等金属进行了分析。还测定了水中的铜结合配体。当没有水华发生时，两个地点水和沉积物中的平均金属水平在统计学上没有差异。因此，认为阿马兰特没有蓝藻水华不是由于金属含量的差异。当马尔科 - 德卡纳韦塞斯发生水华时，沉积物中的金属水平同时显著增加。沉积物质量指南表明，在此期间，铜和铅的浓度（分别为32.3和43.2毫克/千克）具有潜在毒性。然而，可交换金属部分的定量分析表明这些金属可能无法被生物利用。水华中水中铜结合配体的浓度较高，表明蓝藻能够在水库中原位改变金属的形态。
