| Fish-scale-deposition rate (SDR) of 47 surface sediment samples and 6 sediment cores from central Yellow Sea, changjiang estuary, fujian and zhejiang coastal area have been investigated in this study, to reveal fish-scale-deposition information and spatial distribution in typical fishery sea area. This study proved the feasibility of applying SDR to trace fish population fluctuations in Yellow Sea, and made the preparation for reconstruction of long-term fish population fluctuations.Results showed that Anchovy (Engraulis japonicus) and Pacific herring scales are often fragmented and damaged while small yellow croaker, acropoma japonicum, white croaker and Setipinna taty scales are often >50% intact.The species composition of fish-scale-deposition in central yellow sea was simple. Anchovy (Engraulis japonicus) and small yellow croaker (Pseudosciaena polyactis) were the major fish in Yellow Sea. In surface sediment anchovy made up 75.00% and small yellow croaker made up 25.00%. The positions where found scales, distributed on northwest and southeast edge of central Yellow Sea approximately, and SDR was high around 10594 position (34°59.9′N, 122°29.9′E) and 12694 position (33°59.9′N, 123°59.0′E).The vertical distributions of SDR of 3 positions in central Yellow Sea were inhomogeneous with depth increasing. Determined on the basis of 210pb analysis, the deposition rates of 10594 and 12694 position are 0.350cm/a, 0.153cm/a respectively, and the sediment was undisturbed. The estimation of deposition rates of 10794 core is 0.1cm/a. The correlation analysis between the Anchovy SDR of three cores show that, the correlation between 10594 and 10794 is significant at the 0.05 level. The last 150 years anchovy population fluctuations in Yellow Sea were reconstructed on the recalibrated scale-deposition data. Three peaks of anchovy scales deposition appeared in 1860-1890, 1930-1940, 1980-1990 from 1860 to 2005 and anchovy resource fluctuate at a period of 40-60 years.The small yellow croaker scale deposition record shows that three peaks approximately appeared in 1900, 1930 and 1960. The Pacific herring scales were found only in 10594 position in 1890-1900. After 20 century 70s, fish species composition significant changed on the basis of the species composition of fish-scale-deposition.In changjiang estuary, SDR was lower than that in central yellow sea, and the species composition of fish-scale-deposition was complex. 68.06% scales were identified in changjiang estuary surface sediment; small yellow croaker, acropoma japonicum and anchovy were the major fish, made up 29.17%, 12.50% and 8.33% respectively. The positions where found scales, distributed along central Zhoushan Fishing Ground and paralleled to the coastal line approximately. SDR was high around H-28 position (28°09.1′N, 122°55.3′E). Determined on the basis of 210pb analysis, the deposition rate of H-18 core was 0.225cm/a, but the natural record of sediment was destroyed or distorted by turbulence and the activity of benthic animals. The vertical distributions of SDR in changjiang estuary were irregular, but the same change trend and the major fish that had continuous change trend, did not appear in the vertical distributions of 3 cores.Compared with changjiang estuary, in central Yellow Sea the SDR is higher and the sedimentary environment, material resource and deposition are more stable. Central Yellow Sea is the more appropriate area for applying SDR to reconstruct fish population fluctuations.
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