中文摘要：

金属元素进入水体后,威胁水体安全,水生生态系统功能受损。常规的金属离子浓度测试,反应了金属污染强度,但不能反应金属污染对当地生态系统的影响,因此,建立金属污染生物指示系统至关重要。硅藻是水生生态系统中的重要初级生产者,因其种类多、代时短、对环境因子敏感,在发达国家已广泛应用于常规水质监测。在金属胁迫下,硅藻在单个细胞水平与群落结构水平产生应答,基于此发展了一系列指标如生物量、指示物种、群落结构多样性、硅藻畸形率、植物螯合肽等应用于指示金属污染。对近几年硅藻应用于金属污染指示取得的进展予以综述,并提出系统性整合各项指示技术,根据室内与野外模拟结果分配各项指标权重,将是应用硅藻指示水体金属污染的重要途径。

英文摘要：

Heavy metal pollution of aquatic habitats is a major and persistent environmental issue,and has serious bad effect on aquatic ecosystem and human health. The monitoring of the heavy metal concentration could directly reflex the intensity of heavy metal pollution,but could not demonstrate the influence in the ecosystem,so it＇ s urgent to establish a biological indicator system to detect the effect of heavy metal pollution on the ecosystem. Diatoms,as one of the most important global primary producers,have been widely used for water quality assessment,especially for eutrophication water body and organic matter pollution. They can also be used as reliable indicators for metal pollution. Research has shown that diatom could respond to the heavy metal stress both at the single-cell level and at the level of community structure. In that case,many diatom-based indicators,such as diversity,diatom metrics,cell deformation and phytochelatin synthesis were proposed for the assessment of metal pollution. Generally,the indicators work well in the assessment of metal polluted sites. However,diversity and diatom metrics do not account for adverse metal effects in all cases,especially for the dredge-related metal pollution. Meanwhile,different diatom species respond to metal pollution differently,thus indicators based on a single index such as cell deformation or phytochelatin might not explain the metal pollution accurately. In a word,diatom undoubtedly has the potential to identify metal-related stress,though it is still a challenge to quantify the stress with single parameter.An approach integrating various levels of diatom-based indicators would be more promising in the metal pollution assessment.