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Study of the Coupling Relationship between Micro-CT Character of Carp Otolith and the Heavy Metals in Waters

Author: ZuoLiNa
Tutor: LiShengRong
School: Chinese Geology University (Beijing)
Course: Mineralogy,petrology, Mineral Deposit Geology
Keywords: Carp otolith Heavy metal elements Micro-CT Standard Type Characteristics
CLC: P584
Type: Master's thesis
Year: 2009
Downloads: 75
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Abstract

The fish otolith become good environmental information carrier biologically inert, objective record of the enrichment of the historical changes of the water environment and the low concentration of pollutants. Home and abroad to carry out the the fish otoliths lakes water quality assessment and dynamic monitoring study is mainly based on micro-chemical analysis of water and otolith, to find all kinds of simple and sensitive standard features confirmed the presence of fish otoliths and water quality must coupling relationship is also very necessary. Baiyangdian water quality environment quite different and the Miyun Reservoir carp two research areas the otolith as research object, the first time the X-ray tomography (CT) and Micro-CT technology to carp otoliths of heavy metals in the water environment response relationship study of the elements, while taking advantage of XRD, SEM, LA-ICP-MS technologies such as carp otolith phase, the elements of the structure, morphology and enrichment, scanning electron microscope of clearly observed vector ear Stone Japanese round rings boundaries; micro-XRD experiments quarry species and the crystal structure of the two carp ear no holistic, but the cell parameters are slightly different cell parameters of the Baiyangdian waters noticeable distortion tendency micro otolith lattice parameters a generally smaller than the standard lattice parameters a, the sagittal otolith cell parameters a also generally smaller than the standard lattice parameters a and cell parameters b, c generally larger than the standard cell parameters, the ears of the Miyun Reservoir stone cell parameters fluctuate near the standard cell parameters, no significant law; LA-ICP-MS analysis showed that the content of the Baiyangdian waters otoliths Cu and Pb content is greater than the corresponding elements of the Miyun Reservoir, Miyun Reservoir otolith constant The elements Mg content above the the Baiyangdian waters otolith Mg content; Micro-CT experimental data statistics show that the the Baiyangdian waters carp otolith Micro-CT values ??higher than the Miyun Reservoir carp otolith Micro-CT values. The above experimental results and comprehensive analysis of the data showed that: basic water quality of the study area will not affect the choice of the otolith calcium carbonate polymorphs, but slightly affected cell parameters, major elements Mg, Ba and heavy metals Cu, Pb, and common leading to calcium carbonate distortion of the unit cell parameters. The degree of enrichment of heavy metal elements Cu and Pb is the main reason that led to two study area waters Micro-CT value differences. Atomic number of Cu and Pb in the Baiyangdian waters carp otolith content, and directly led to the generation of high-density voxel, Cu and Pb collisions when the X-ray incident process, due to the coefficient of Cu and Pb atoms , the electron binding energy of high, high density, atomic structure most closely, the X-rays can be absorbed, i.e. the X-ray absorption coefficient, leading to Micro-CT value. In summary, the use of Micro-CT experimental data statistical comparison reflects the atomic number of heavy metals in the carp otolith information. Elements in the otoliths and water elements have similar trends in the distribution and enrichment of the corresponding element in Water. Therefore, the the carp otoliths Micro-CT features of the water environment of heavy metal elements coupling, can be used as a standard-type characteristics indication of heavy metals in water information.

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