Otolith Elements Of Synechogobius Ommaturus

Otoliths of teleost fishes are small, calcareous structures located within the inner ear, whose primary function appears to be the detection of sound and the balance of body. In exchange with fish and the water, the ions pass from the water into blood plasma by way of gills and digest system, Endolymph chemistry and otolith growth in fish and then deposit into otolith by metabolism. Otolith is metabolic inertness, i.e. it is acellular and physiologically static, once accreted, material is not resorbed or metabolically reworked. The deposit of ions were influenced by the concentrations of ions in the water, temperature, salinity and so on, so the concentration of element can reflect the environment of water. In recent years, otolith has been used abroad in population and stock identification, environment indication, life-history reestablishment with the process of analysis instrument(ICP-MS, Inductively Coupled Plasma Mass Spectrometry; EPMA, Electron Probe Micro Analysis; LA-ICP-MS, Laser Ablation Inductively Coupled Plasma Mass Spectrometry), but it is rarely in China. Based on otoliths collected from the recent research programms such as "908" special project of State Oceanic Administration of People's Republic of China, National Basic Research Program of China (973 program) (No.2005CB422306), etc., the concentrations of ten elements(K, Ca, Na, Mg, Sr, Pb, Ba, Mn, Co, Zn) of Synechogobius ommaturus otoliths that from eight locations(Dandong, Dalian, Tianjin, Dongying, Weihai, Qingdao, Ganyu, Xiamen)were measured by ICPMS. The aim of this study were to:(1) analyse the difference among sites; (2) provide base values of otolith chemical composition. The main findings were as follows:(1) Regression analysis were performed using body weight and standard lengt(2) In order to remove the potential effect of otolith weight on the elemental composition of the otolith, the concentration of each element was regressed against otolith weight. When a regression was significant, the residuals of the regression were used instead of the original concentrations in the subsequent analyses. In this study, Otolith weigh has a significant effect on Mn and K only. (3) Differences between male and female were tested by ANOVA, there was no significant difference between male and female(p>0.05)。(4) Differences in element concentrations among sites, or the residuals of the regression against otolith weight when appropriate were tested with ANOVA. There was significant difference among sites for Sr, Co, Ba, Pb and Sr/Ca by ANOVA; for K and Mn and the residuals (concentrations on otolith weight), there was significant difference; Sr/Ca has no significant difference among sites.(5) Cluster analyses were performed using the residuals of the regressions of elemental concentrations against otolith weight when appropriate. Dalian simples(collected from the aquaculture ponds) is different with simples from other locations.(6) Discriminant analyses were performed using the residuals of the regressions of elemental concentrations against otolith weight when appropriate. The average discriminant accuracy of the eight locations is 80.3%, the accuracy of Weihai and Xiamen are 100%.