扬子鳄栖息地重金属含量及生物积累  

Heavy Metal Content and Bioaccumulation in Habitats Used by Alligator sinensis

作　　者：党雅婷 沈悦悦 章松 蒋宣清 晏鹏[1] DANG Ya-Ting;SHEN Yue-Yue;ZHANG Song;JIANG Xuan-Qing;YAN Peng(College of Life Sciences,Anhui Normal University,Wuhu 241000;Chinese Alligator National Nature Reserve Administration in Anhui,Xuancheng 242099,China)

机构地区：[1]安徽师范大学生命科学学院,芜湖241000 [2]安徽扬子鳄国家级自然保护区管理局,宣城242099

出　　处：《动物学杂志》2025年第1期80-92,共13页Chinese Journal of Zoology

基　　金：安徽省研究生教育质量工程项目(No.2022zyxwjxalk027)。

摘　　要：为了评估扬子鳄(Alligator sinensis)栖息地面临的重金属污染风险及长期生物积累,本研究于2021年5月和10月在安徽扬子鳄国家级自然保护区的8个样地内对水塘中的水、底部土壤沉积物以及圈养扬子鳄的饲料和已孵化的卵壳进行了重金属检测。8个样地中,夏渡样地生活着圈养扬子鳄种群,朱村、高井庙、杨林、红星、双坑、中桥和长乐样地为野外种群栖息地。研究聚焦于汞(Hg)、镉(Cd)、铜(Cu)、锌(Zn)、铬(Cr)、砷(As)和铅(Pb)7种重金属元素,采用综合污染指数(R)和地质积累指数(Igeo)评估污染等级。使用独立样本t检验分析5月与10月环境样本中重金属含量的差异,以生物富集系数(BCF)和生物放大系数(BMF)分析卵壳中重金属元素的生物积累情况。结果显示:1)5月和10月的栖息地水环境中As、Cu和Zn的含量存在显著差异,但水环境总体无污染(R<1)。仅Hg含量高于《地表水环境质量标准》,因此Hg具有潜在威胁;2)5月和10月的栖息地土壤沉积物中Hg、Zn、Cr和Cd的含量差异显著,其中Cd在5月表现为无污染,10月上升至偏中度污染(Igeo=1.56),而Hg在5月(Igeo=0.77)和10月(Igeo=0.30)均表现为轻微污染;3)卵壳中Cr和Pb含量超标,夏渡样地的数值高于其他样地;4)水环境中Cu和Zn(夏渡样地)的生物富集系数范围为2.05~38.61,卵壳对饲料中As、Cu、Zn和Cr的生物放大系数范围为1.26~4.64。本研究表明,Cu和Zn通过水环境积累于卵壳中,而圈养扬子鳄卵壳中的重金属也通过食物链积累。土壤沉积物中长期积累的Pb元素可能导致卵壳中Pb含量超标。值得注意的是,圈养扬子鳄卵壳中的重金属含量高于野外种群。重金属污染物通过环境和食物链的生物积累可能已经对保护区内扬子鳄的生殖产生了负面影响。因此,控制栖息地环境中Hg和Cd污染源并加强饲料的安全性是当务之急。[Objectives]This study aims to assess the risks of heavy metal pollution and long-term biological accumulation faced by the habitat of Alligator sinensis.In May and October 2021,heavy metal concentrations in water,soil sediments,feed for captive A.sinensis,and hatched eggshells were tested in eight sample areas within the National Nature Reserve of Chinese Alligator in Anhui Province.Among these,the Xiadu area hosts a captive population,while the Zhu Village,Gaojingmiao,Yanglin,Hongxing,Shuangkeng,Zhongqiao,and Changle areas harbor wild populations.The research focused on seven elements:mercury(Hg),cadmium(Cd),copper(Cu),zinc(Zn),chromium(Cr),arsenic(As),and lead(Pb).[Methods]The pollution levels in water and sediment contamination were evaluated using the comprehensive pollution index(R)and the Muller index(Igeo).Independent samples t-tests were used to analyze the differences in heavy metal concentrations between the environmental samples from May and October.To minimize harm,hatched eggshells were utilized to investigate heavy metal bioaccumulation instead of live individuals.The biological enrichment coefficient(BCF)indicated the accumulation of heavy metals from the environment,while the biological magnification coefficient(BMF)represented accumulation through the food chain.[Results]1)Significant differences were observed in the concentrations of As,Cu,and Zn between the water samples from May and October(Table 1).In comparison to October,As and Zn concentrations were higher in May,while Cu concentrations were lower during that month.The comprehensive pollution index indicated that the water environment was free from heavy metal pollution(R<1).However,the concentration of Hg exceeded the“Environmental Quality Standards for Surface Water,”suggesting that Hg poses a potential threat.2)Significant differences were also noted in the concentrations of Hg,Zn,Cd,and Cr in the sediment between May and October(Table 2).Compared to October,Hg and Zn concentrations were higher in May,whereas Cd and Cr concentratio

关 键 词：扬子鳄 栖息地 重金属 生物积累 

分 类 号：Q958[生物学—动物学]