| 摘要: |
| 旨于探索沉积剖面元素迁移强度的描述方法,讨论向海沼泽湿地沉积物化学元素的迁移积聚等基本地球化学特征,以深化对沼泽湿地沉积化学行为的某些认识。冬季在向海两处沼泽采集了代表一定范围汇水区与人类活动影响的沉积芯。利用Tessier等(1979)提出的连续提取法对沉积物中多种常量与微量元素地球化学相进行分离。可迁移系数、潜在迁移系数、非迁移系数的计算结果表明,在向海沼泽沉积剖面中,化学元素相对迁移强度为:Ca、Sr、Mn、Pb潜在活性最大,Ti、Al、K、Rb潜在活性最小,以此为依据,Ti、Al、K、Rb等元素适宜作为示踪元素。为消除沉积物构成组织的影响,以Al为参考元素对重金属元素形态两种分量进行归一化后,重金属环境非迁移分量与相对迁移分量均表现出在表层的富集,尤其表现在上游霍林河煤矿开发后20余年这一时期,人类活动的介入加速了重金属元素通过河流搬运向下游湿地的输入。 |
| 关键词: 向海沼泽湿地 沉积物 元素化学形态 迁移率 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目,40471136号;吉林省生态恢复重点实验室开放基金资助项目,DS200401号 |
附件 |
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| THE MOBILITY OF CHEMICAL ELEMENTS IN SEDIMENT CORES IN XIANGHAI WETLAND |
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WANG Guo-Ping1, LIU Jing-Shuang1, TANG Jie2
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1.Northeast Institute of Geography and Agricultural Ecology,Chinese Academy of Sciences,Changchun,130012;2.College of Environment and Resources,Jilin University,Changchun,130026
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| Abstract: |
| The Xianghai Wetland, 360km2, at 45°02'N 122°41'E is an alluvial geomorphic wetland in Xianghai National Nature Reserve, situated in western border of the Songnen Plain in Northeast P. R. China, a typical region where rivers and lakes are met. It has been listed in The List of Wetlands of International Importance (RAMSAR Site No. 548) since 1992. The wetland strides across semi-arid climatic zone and receives hydrological inputs mainly (about 55.2%) from the Huolin River that originates from the Great Xing’an Mountains, running 320 km and merges in to the wetland in the end. Ecologically, the wetland covers a transition zone between terrestrial and aquatic systems, receiving sediment inputs from them. To explore the mobility of chemical elements in sedimentary profiles for understanding the local pollution spreading mechanism in upstream areas, we conducted this study in 2000 on the marsh wetland in downstream of Huolin River. Sixty-one sediment samples were cored, 108cm long in a range covering 15000 hm2 characteristic of natural and anthropogenic impacts, in winter on 120 cm-thick-frozen layer in two marshes of the wetland. High resolution of isotopic dating with 210Pb and 137Cs shows that the age of the sediment was formed between 1760 to 1763 and chemical analysis using Tessier method on common five chemical forms of major and trace elements in typical sedimentation profiles revealed that K, Ca, Sr, Mn and Pb are potentially mobile elements in a descending order, while Ti, Al, K and Rb are immobile that selectable for use as tracing elements in environmental research. After normalization with Al for eliminating influence of sedimentary composition, we found that the non or relatively mobile fractions in the environment were tended to concentrate at the surface. In fact, the enrichment became more obvious in recent 20 years during which an open-pit coalmine (Huolinhe Coal Mine) was put into operation. In conclusion, human activities have speeded up the heavy metal transportation from river upstream to the wetland, which has damaged the land for obvious reason. |
| Key words: Xianghai Wetland, Sediments, Chemical forms of element, Mobility |
