滇西北剑湖沉积物钒空间分布特征和生态风险

用电感耦合等离子体发射光谱仪（ICP-OES）测定剑湖表层及柱状沉积物钒（V）含量，采用改进BCR连续提取法提取V各形态，并对V空间分布特征和生态风险进行了分析，揭示了粒度对剑湖沉积物V及形态含量的影响.结果表明，剑湖表层沉积物和柱状沉积物颗粒均以粉砂粒和细砂为主，细颗粒V含量更高.表层沉积物V含量为（117.82±63.31）mg/kg，其水平空间分布差异较大.V可交换态、可还原态、可氧化态和残渣态含量分别为（8.91±8.91），（18.36±10.53），（7.67±7.67），（80.22±58.71）mg/kg，主要以残渣态形式存在，且黏粒和粉砂粒对V可还原态和残渣态影响较大.V垂直分布差异大，底层V含量高于表层，少部分区域受黏粒和粉砂粒影响.剑湖沉积物V污染程度小，大部分地区潜在生态风险较低，底层沉积物污染程度和潜在生态风险都高于表层.

Spatial distribution characteristics and ecological risks of vanadium in sediments from Jianhu Lake,Northwest Yunnan Province,China

The inductively coupled plasma-optical emission spectrometer (ICP-OES) was used to determine the concentrations of vanadium in surface and columnar sediments from Jianhu Lake. The modified BCR sequential extraction method was used to extract the different fractions of vanadium, and then the characteristics of spatial distribution and ecological risks of vanadium were assessed, the effects of sediment particle size on the concentrations of vanadium and its fractions were also studied. The results showed that the sediment particles in surface and columnar sediments in Jianhu Lake were mainly composed of silt and fine sand, and the concentrations of vanadium in fine particles were higher. The concentration of vanadium in surface sediments from Jianhu Lake was (117.82±63.31)mg/kg, and its horizontal distribution varied substantially. The concentrations of vanadium in exchangeable, reducible, oxidizable, and residual fraction were (8.91±8.91), (18.36±10.53), (7.67±7.67), (80.22±58.71) mg/kg, respectively. This indicated that vanadium mainly presented in the form of residual fraction. Furthermore, the clay and silt in sediments had a great influence on the reducible and residual fractions of vanadium. The vertical distribution of vanadium also varied greatly, and the concentration of vanadium in bottom sediments was higher than that in surface layer. In addition, the concentrations of vanadium were affected by clay and silt in some areas of Jianhu Lake. The degree of vanadium pollution was mild in sediments from Jianhu Lake, and the potential ecological risks of vanadium were low in most areas. The contamination levels and the potential ecological risks of vanadium in the bottom sediments were higher than those in surface layer.