香港河流及近海表层沉积物和孔隙水的毒性研究

Studies on toxicity characteristics and factors in sediment and porewater of rivers in Hong Kong

采集并测定了香港重点监测河流河口及近海处的表层沉积物、孔隙水样品的理化特征及生物毒性 ;对比了沉积物与孔隙水、孔隙水与上覆水、经过不同处理的孔隙水以及加入重金属前后沉积物与孔隙水的毒性 ,并进行了浸提实验及其毒性测定 .研究结果表明 ,当重金属的含量很低时 ,沉积物孔隙水中硫化物和非离子氨可能是引起孔隙水毒性的最主要因素 ;在SEM AVS小于 1的情况下 ,沉积物的毒性与SEM AVS的值无关 ,其毒性取决于沉积物中AVS及其他有机物的含量 ;

Contents and toxicity of sediments and porewater in rivers of Hong Kong were measured and compared.Toxicity between sediment and porewater,porewater and overlaying water,porewater under different treatments were compared separately.Elutriate experiment was also conducted.The results show that sulfide and non ion ammonia would be the main factors on toxicity of sediment when contents of heavy metals are very low.When ratio of SEM and AVS is below 1,toxicity of sediment shows independence with the ratio of SEM and AVS,and the main factors may be AVS and other organic materials in sediment.Elutriate experiment could hid the true toxicity of sediment,because it had destroyed the active sulfide.