山同河沉積物重金屬形態(tài)分析及生態(tài)風(fēng)險(xiǎn)評(píng)價(jià)

摘要：為了解峒河水體沉積物中重金屬的污染現(xiàn)狀及其潛在生態(tài)危害程度，采用改進(jìn)的“BCR提取法” 對(duì)峒河水體沉積物中重金屬元素Cr、Pb、Cu> Zn、Cd的形態(tài)分布特征進(jìn)行了分析，利用潛在 生態(tài)風(fēng)險(xiǎn)指數(shù)法對(duì)其進(jìn)行了綜合評(píng)價(jià)。形態(tài)分析結(jié)果表明，峒河沉積物重金屬含S均高于湖南省土壤背 景值，其中Zii的含ffl最高，Cu的含S最?。凰膫€(gè)采樣點(diǎn)中有效性排序?yàn)镃d>Pb>Zn〉Cu〉Cn其中Cd的有 效性最高，Cr的有效性最低；沉積物潛在生態(tài)風(fēng)險(xiǎn)評(píng)價(jià)結(jié)果表明，峒河表層沉積物中主要的重金屬污染 因子是Cd,各種重金屬的潛在生態(tài)危害系數(shù)大小順序?yàn)镃d>Pb>Zn〉Cr〉Cu;重金屬的潛在生態(tài)風(fēng)險(xiǎn)水平 較高，四個(gè)采樣點(diǎn)均為嚴(yán)重生態(tài)風(fēng)險(xiǎn)。
關(guān)鍵詞：重金屬；峒河沉積物；形態(tài)分析；潛在生態(tài)風(fēng)險(xiǎn)；BCR提取法

Speciation Analysis and Ecological Risk Assessment of Heavy Metal
in Water Sediment of Dong River
Abstract： In order to find out the present condition and potential ecological hazard of heavy metal contamination, Speciation distribution of Cr? Pb，Cu，Zn, Cd in water sediment of Dong River were analyzed and comprehensive eva luated separately by reformative BCR extraction and Hakanson potential ecological risk index method. The results of speciation analysis showed that the content of heavy metal elements in sediment of Dong River all exceeded the soil background value of Hunan Province，Cd had the top content while Cu was on the contrary; Valid order of four different spots was Cd〉Pb〉Zn〉Cu〉Cr，Cd had the top validity while Cr was on the contrary; The result of potential ecological risk assessment of sediment showed that the main heavy metal pollution element was Zn; The potential ecological hazard coefficient of different heavy metal element was Cd>Pb>Zn>Cr>Cu； the level of potential ecological risk of heavy metal in the surface sediment of Dong River was comparatively high. Ecological risk level of four different spots were all serious.
Key words： Heavy metal，Dong river sediment, Speciation analysis，Potential ecological risk,
BCR extraction