珠江河口及近海水域中Cu的形态分布及其对藻类的生物毒性

Copper speciation in Pearl River Estuary and its bioavailability to aglae

对珠江河口及近海水域样品中Cu的总含量以及颗粒态、游离态Cu含量进行分析,结果发现,Cu的总浓度有随河口向外海递增的趋势,并非完全体现陆源性规律。说明研究水域中Cu不仅可能具有其他来源,同时在很大程度上受到沿岸上升流的影响。但是游离态Cu的分布却表现相反的规律,无论是游离态Cu的浓度还是游离态Cu在总Cu中所占的份额都自河口向外海随盐度的增加而降低。说明Cu的形态分布在更大程度上取决于水体的理化性质。本研究还通过对不同盐度水样的杜氏藻培养后Cu吸收量的测定,即通过Cu对藻类的生物有效性验证了Cu形态的分布规律。

The contents of total copper, particulate copper, and free copper ion in the samples obtained during the cruise on July 2002 in the Pear River Estuary were measured. It was found that, even though the total copper contents increased with salinity, the concentrations of free copper ion and the ratio of free copper ion to total copper decreased with the salinity of water. It could conclude that, except the run off from the river, there must be other sources of copper to the Pear River Estuary; and the upwelling affected the copper contents and its speciation distribution heavily. In this study, the copper uptake by Dunaliella tertiolecta was also analyzed after cultivating in water samples from different station in order to verify the copper speciation distribution character in the Pear River Estuary.