蟹类活动对河口潮滩沉积物重金属分布的影响

利用现场样方调查以及室内蟹箱模拟试验,研究了蟹类的掘穴、取食等活动对河口潮滩沉积物中Cu、Pb、Fe、Mn、Zn、Cr等重金属分布的影响.结果表明,蟹类活动可以显著地增加潮滩沉积物用以交换的表面积,改变周围沉积物的有机质含量和粒度特征,使沉积物中的重金属含量显著增加,为在沉积物-水界面发生的重金属交换过程提供了更多的物质来源.蟹类活动对沉积物中重金属垂向分布的影响与沉积物类型密切相关.图6表1参10

Effect of Crab Activities on Distribution of Heavy Metals in Estuarine Intertidal Sediments

Based on the field quadrat investigation of crab holes in intertidal sediments, together with the experiment of crab activities in a box, the effects of crab activities, such as digging tunnels and eating, on the distribution of Cu, Pb, Fe, Mn, Zn and Cr in intertidal sediments were studied. The results showed that the surface areas of intertidal sediments for exchanging could be obviously increased by crab activities. The content of organic matters in the sediments and the characteristics of particle size around the tunnels made by crabs could also be changed, resulting in an increase of heavy metals in sediments and providing more heavy metal sources for the exchanging process at the sediment-water interface. The effect of crab activities on the vertical distribution of heavy metals in sediments was closely related to the texture of sediments.