【摘要】：對(duì)取自浙江近岸泥質(zhì)區(qū)的柱狀樣DZ-28沉積物進(jìn)行了粒度分析、210Pb和137 Cs同位素測(cè)年分析以及常量元素和重金屬元素(As、Cd、Cr、Cu、Hg、Pb和Zn)含量分析,并用綜合污染指數(shù)和潛在生態(tài)危害指數(shù)評(píng)價(jià)了近140年來(lái)研究區(qū)重金屬污染程度的變遷。結(jié)果表明:柱狀樣沉積物的平均沉積速率為0.85cm/a;Al、Fe、K、Mn和Mg的含量與中值粒徑具有相似的變化趨勢(shì),它們?cè)?0世紀(jì)80年代后含量逐漸增加,而Si和Ca則具有相反的變化趨勢(shì),這可能是由長(zhǎng)江流域內(nèi)大壩修建等一系列水利工程建設(shè)和上游水土保持工作的廣泛開(kāi)展所引起的;重金屬元素含量在1982年前基本保持不變;在1982—2005年間均出現(xiàn)較大幅度增長(zhǎng),表明長(zhǎng)江流域的人類(lèi)活動(dòng)強(qiáng)度在80年代后顯著增加,導(dǎo)致巨量的重金屬污染物被釋放到長(zhǎng)江中并被輸送到研究區(qū)域,從而導(dǎo)致沉積物中這些元素的絕對(duì)含量明顯升高;2005年后,Cu、Cr和Zn的增加趨勢(shì)減緩,表明該時(shí)期內(nèi)我國(guó)的環(huán)保政策等措施有效地控制了重金屬污染物的排放,而Pb含量的增加可能與這一時(shí)期三峽大壩蓄水有關(guān);研究區(qū)的重金屬綜合污染程度和潛在生態(tài)危害程度均低,表明近140年來(lái)研究區(qū)所面臨的生態(tài)風(fēng)險(xiǎn)程度很低。近140年來(lái)重金屬分布及演化特征與長(zhǎng)江流域經(jīng)濟(jì)發(fā)展和國(guó)家環(huán)境保護(hù)政策等人類(lèi)活動(dòng)密切相關(guān)。
[Abstract]:The grain-size analysis of columnar DZ-28 sediments taken from the muddy area of Zhejiang Province was carried out. The isotopic dating of 210Pb and 137 Cs and the contents of major elements and heavy metal elements (As,Cd,Cr,Cu,Hg,Pb and Zn) were analyzed. The changes of heavy metal pollution in the study area during the past 140 years were evaluated by comprehensive pollution index and potential ecological hazard index. The results show that the average deposition rate of columnar sediments is 0.85 cm / a, and the contents of mn and Mg in Alanfen Feankek are similar to those of the median particle size. The contents of mn and Mg in columnar sediments increase gradually after 1980s, but Si and Ca have the opposite trend. This may be caused by a series of water conservancy projects such as dam construction in the Yangtze River basin and extensive development of soil and water conservation work in the upper reaches; the content of heavy metal elements remained basically unchanged before 1982; and between 1982 and 2005, there was a considerable increase in the content of heavy metals. The results show that the intensity of human activities in the Yangtze River basin increased significantly after the 1980s, resulting in the release of heavy metal pollutants into the Yangtze River and their transport to the study area. As a result, the absolute content of these elements in sediments increased obviously, and the increasing trend of Zn and Cr decreased after 2005, which indicated that the environmental protection policies and other measures effectively controlled the emission of heavy metal pollutants in this period. However, the increase of Pb content may be related to the water storage of the three Gorges Dam in this period, and the comprehensive pollution degree and potential ecological hazard degree of heavy metals in the study area are both low, which indicates that the ecological risk in the study area is very low in the last 140 years. The distribution and evolution of heavy metals in the last 140 years are closely related to human activities such as the economic development of the Yangtze River Basin and national environmental protection policies.
【作者單位】： 山東科技大學(xué)地球科學(xué)與工程學(xué)院;中國(guó)地質(zhì)調(diào)查局青島海洋地質(zhì)研究所;國(guó)土資源部海洋油氣資源和環(huán)境地質(zhì)重點(diǎn)實(shí)驗(yàn)室;
【基金】：國(guó)家自然科學(xué)基金項(xiàng)目(41330964;41306063) 泰山學(xué)者工程專(zhuān)項(xiàng)經(jīng)費(fèi)資助 中國(guó)地質(zhì)調(diào)查局地質(zhì)調(diào)查項(xiàng)目(GZH201200506)
【分類(lèi)號(hào)】：P736.21;X55
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本文編號(hào)：2201036