胶州湾养殖海区沉积物中酸可挥发性硫的研究

Study on Acid-volatile Sulfide(AVS) of Sediment in Mariculture Region of Jiaozhou Bay

沉积物中酸可挥发性硫化物 (AVS)的含量对控制重金属在沉积物 /间隙水中的分配和重金属的生物可利用性方面有重要意义 ,也是海洋养殖业的重要指标之一 ,研究改正目前《海洋监测规范》中沉积物酸可挥发硫化物的测定方法基础上 ,建立了一套简单易行的仪器装置和分析程序。讨论了N2 流量、反应时间、酸强度、硫总量 4个方面对测定结果的影响。给出了胶州湾海区沉积物中AVS的定量数据。表明胶州湾养殖海区沉积物中AVS的含量显著高于非养殖海区和其它海湾沉积物中AVS的含量。

Acid volatile sulfide is operationally defined for the analysis of sulfide in aquatic sediment The AVS has been shown significance in controlling heavy metal partitioning between sediment and pore water and in explaining the bioavailability of metal toxicants Also,it is an important index of sediment quality in mariculture This paper describes apparatus that can be used in the evolution of sulfide from sediment and a method for the analysis of the evolved sulfide The method was studied with respect to N 2 gas flow rate,reaction time,acid concentration and sulfide amounts The evolution of sulfide was determined by iodimetric methods of analysis Using the apparatus and conditions described in this paper,the iodimetric method of analysis is capable of detecting AVS at concentration normally encountered with a recovery of sulfide of at least 90% Meanwhile,samples of sediment were compiled from mariculture region of Jiaozhou Bay and shrimp ponds and the AVS concentration was determined by this approach The average concentration of AVS in mariculture sediment was 11 41 μmol/L, which was higher than that in shrimp ponds and other natural marine sediment The richness of AVS in sediment of northeast region of Jiaozhou Bay was likely resulted form the discharge of mariculture waste water Furthermore, it was discussed for the method of normalization by AVS in predicting chemical activity and bioavailability of divalent metal