江西德兴铜矿区大坞河流域环境介质中Cu含量变化趋势

Trend analysis of Cu contamination in environmental media of the Dawu River in the Dexing copper mine, Jiangxi Province

以2004年和2011年江西德兴铜矿开采区影响的大坞河流域共计140件水、土、底泥及种植物样品中Cu的含量为研究对象,参考国家标准对大坞河流域不同河段Cu污染进行评价,研究不同环境介质中Cu含量随时间变化的规律,并且探讨种植物中Cu元素的来源。研究表明,从空间上看大坞河源区和上游的样品超标率最高,分别达到70.3%和90.9%。7年间研究区环境介质中的Cu元素总体是趋于恶化的,除地表水和土壤中Cu含量有所降低外,其他环境介质中的Cu含量都有所增加,最明显的是2011年小白菜中的Cu元素含量是2004年的11.68倍。与种植物密切相关的地表水和对应土壤中Cu元素的变化规律存在较大差异,据此推断其Cu元素来源与元素形态、大气干湿沉降等因素有关。

In 2004 and 2011, 140 environmental media samples were collected along the Dawu River of the Dexing copper mine in Jiangxi Province and analyzed for Cu. On the basis of the national standard, the spatial-temporal variation of Cu regional environ-ment contamination and the source of heavy metals in plants were studied during the seven years. The results show that the samples whose values exceeded the national standard were mostly distributed at the source （70.3%） and in the upstream area （90.9%） of the Dawu River. Except for the surface water and soil, the trend of Cu in environmental media in 2004 and 2011 was on the whole worsening. And the cabbage whose content of Cu element in 2011 was 11.68 times that in 2004 seemed to be the obvious environ-mental media. There existed obvious differences of the variation regularity between plants and other environmental media such as sur-face water and soil. It is inferred that the source of Cu in plants has close relation with atmospheric deposition.