中文摘要：

采用液-液萃取法和ICP-MS测试技术对巢湖的溶解态稀土元素进行了分析。结果表明，巢湖的溶解态稀土的含量与世界淡水相当，丰水期的样品含量高于其他季节。pH值和悬浮物、胶体是控制巢湖水体中溶解态稀土含量的主要因素。巢湖的溶解态稀土的分布模式以平坦型为主，少数呈现重稀土富集。丰水期和枯水期的溶解态稀土的（La／Yb）N值从西半湖区到东半湖区呈现有规律性的逐渐增大，并且丰水期的（La／Yb）N值低于枯水期。在富营养化湖泊中，胶体和水生生物可能是造成这一现象的主要原因。

英文摘要：

The dissolved rare earth elements （REEs） in the aquatic environment of Lake Chaohu were determined by inductively coupled plasma mass spectrometry （ICP-MS） after solvent extraction and back-extraction. The results show that the concentrations of dissolved REEs in Lake Chaohu are similar to those in freshwater of the world. Furthermore, these concentrations of dissolved REEs during high-water period are clearly higher than those during low-water season. The concentrations of dissolved REEs are mainly controlled by pH and the concentration of suspended and colloidal particles. The dissolved REEs in most lake waters show fiat NASC-normalized REE patterns, but a few samples showing heavy REE enrichment relative to NASC. The values of （La/Yb）N in highwater period and low-water season increase from west to east, and they in high-water period are larger than those in low-water season. These phenomena might be mainly resulted from colloidal particles and hydrophytes in the eutrophication lake.