以安徽省铜陵市杨山冲铜尾矿库复垦区(覆土复垦)和未复垦区生长的剑叶金鸡菊(Coreopsis lanceolata Linn.)为研究对象,对2个区域剑叶金鸡菊根际尾矿的基本理化性质和6种重金属元素含量进行了比较,并对2个区域剑叶金鸡菊不同器官的重金属元素含量及其转移系数和富集系数,以及Ca和总磷含量及其比值(R)进行了比较;在此基础上,对不同器官重金属元素含量与根际尾矿相应重金属元素含量以及相应器官Ca和总磷含量及R值进行了Pearson相关性分析.结果表明:2个区域的根际尾矿均偏碱性;复垦区根际尾矿的电导率及有机质、总碳、总氮、总磷、速效磷、速效钾、Cu、Zn、Pb和Cd含量均高于未复垦区;并且,2个区域根际尾矿的Cu、Zn、As和Cd含量均超过国家土壤二级标准.2个区域剑叶金鸡菊各器官的Cu、Zn和Mn含量均较高,而Pb、Cd和As含量较低;主根和须根的Cu和As含量以及茎叶的Cd和Zn含量均较高.与未复垦区相比,复垦区剑叶金鸡菊主根的Zn、Pb、Cd、Mn和As含量较高,而茎叶的重金属元素含量却较低.2个区域剑叶金鸡菊中Cd的转移系数最大,而Cu和As的转移系数分别为最小和未检出;并且,复垦区剑叶金鸡菊中Zn、Pb、Cd和Mn的转移系数显著(P<0.05)低于未复垦区.2个区域剑叶金鸡菊不同器官重金属元素的富集系数大多较低.另外,复垦区剑叶金鸡菊主根的Ca和总磷含量以及须根和茎叶的总磷含量均高于未复垦区.相关性分析结果表明:剑叶金鸡菊主根和须根的Pb含量与根际尾矿的Pb含量分别呈显著和极显著(P<0.01)正相关,茎叶的Cu和Zn含量与根际尾矿的相应重金属元素含量分别呈极显著和显著负相关;主根的Mn含量与Ca和总磷含量呈显著正相关;须根的Cd和As含量与Ca含量分别呈极显著和显著负相关,Mn含量与总磷含量呈显著负相关;茎叶的Cu、Zn和Cd含量与Ca含量以及Cu和Mn含量与R值均呈显著正相关,Mn含量与Ca含量呈极显著正相关.综合分析结果显示:剑叶金鸡菊对6种重金属元素均有一定的吸收和积累能力,属于多重金属耐性植物;并且,覆土复垦可显著降低重金属元素从剑叶金鸡菊根部向茎叶转移,建议将其作为Cu和As污染地植物固定修复的物种.%Taking Coreopsis lanceolata Linn. growing in reclamation(soil covering land reclamation)and non?reclamation areas of Yangshanchong copper tailings in Tongling City of Anhui Province as research objects,basic physicochemical properties and contents of six heavy metal elements in rhizosphere tailings of C. lanceolata in two areas were compared, and contents of heavy metal elements and their transfer coefficient and enrichment coefficient, and contents of Ca and total phosphorus and their ratio(R)in different organs of C. lanceolata in two areas were compared. On the basis, Pearson correlation analysis on contents of heavy metal elements in different organs with those of corresponding heavy metal elements in rhizosphere tailings,and with contents of Ca and total phosphorus and R value in corresponding organs were conducted. The results show that rhizosphere tailings in two areas are alkalescent; electric conductivity and contents of organic matter, total carbon, total nitrogen, total phosphorus, available phosphorus,available potassium, Cu, Zn, Pb, and Cd in rhizosphere tailings of reclamation area are higher than those of non?reclamation area; in addition, contents of Cu, Zn, As, and Cd in rhizosphere tailings of two areas exceed gradeⅡnational soil standard. Contents of Cu,Zn,and Mn in each organ of C. lanceolata in two areas are relatively high,while those of Pb,Cd,and As are relatively low;contents of Cu and As in main and fibrous roots and those of Cd and Zn in stem and leaf are relatively high. Compared with non?reclamation area,contents of Zn,Pb,Cd,Mn,and As in main root of C. lanceolata in reclamation area are higher, while contents of heavy metal elements in stem and leaf are lower. Transfer coefficient of Cd in C. lanceolata in two areas is the largest, while that of Cu and As is the smallest and undetected, respectively; in addition, transfer coefficients of Zn, Pb, Cd, and Mn in C. lanceolata in reclamation area are significantly(P<0.05)lower than those in non?reclamation area. Most of enrichment coefficients of heavy metal elements in different organs of C. lanceolata in two areas are relatively low. Moreover,contents of Ca and total phosphorus in main root,and total phosphorus content in fibrous root and stem and leaf of C. lanceolata in reclamation area are higher than those in non?reclamation area. The correlation analysis results show that there are significantly and extremely significantly(P<0.01)positive correlations of Pb content in main and fibrous roots of C. lanceolata with Pb content in rhizosphere tailings, respectively, and extremely significantly and significantly negative correlations of contents of Cu and Zn in stem and leaf with those of corresponding heavy metal elements in rhizosphere tailings,respectively. There are significantly positive correlations of Mn content with contents of Ca and total phosphorus in main root. There are extremely significantly and significantly negative correlations of contents of Cd and As with Ca content in fibrous root, respectively, and significantly negative correlation of Mn content with total phosphorus content. There are significantly positive correlations of contents of Cu,Zn,and Cd with Ca content and contents of Cu and Mn with R value in stem and leaf, and extremely significantly positive correlation of Mn content with Ca content. The comprehensive analysis results show that C. lanceolata has a certain absorption and accumulation abilities to six heavy metal elements and belongs to multiple heavy metal tolerant plant. In addition,soil covering land reclamation can significantly reduce the transfer of heavy metal elements from root to stem and leaf of C. lanceolata,it is suggested to take C. lanceolata as photostabilization remediation species in Cu and As pollution areas.
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