African Journal of Fisheries Science

ISSN 2375-0715

African Journal of Fisheries Science ISSN 2375-0715 Vol. 10 (1), pp. 001-010, January, 2022. © International Scholars Journals

Full Length Research Paper

Crystal phases of calcium carbonate within otoliths of CYPRINUS  CARPIO. L. from Miyun Reservoir and Baiyangdian Lake, China

Liang-Feng Yang1*, Sheng-Rong Li2, Guo-Wu Li2 and Jun-Yan Luo2

1The Geological Museum of China, Beijing 100034, China.

2State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences, Beijing, 100083, China.

Accepted 12 April, 2021

Abstract

Asteriscus (lagenar otolith) of CYPRINUS CARPIO. L. (Cyprinida, common carp) from the serious intermittent polluted Baiyangdian Lake and the little polluted Miyun Reservoir, all located in northern China, were chemically and mineralogically analyzed. All the analyzed fish showed that the composition of asterisci is dominated by calcium carbonate, with the minor elements As, Ba, Sr, and Zn; and the polymorph of CaCO3 in the asterisci is vaterite. Three different vaterite X-ray diffraction (XRD) patterns were found in the analyzed samples. For the 60% fish from both localities, two different vaterite XRD patterns coexist in the core area and the edge area in same asteriscus sample. Significant differences of the dimensions of crystalline cells of vaterites exist between these two localities, which reveals that crystal structure of vaterite polymorphs seem sensitive to water quality and water environment, its crystalline cell dimensions might be a potential proxy for monitoring the change of water quality.

Key words: Vaterite, biocrystallization, otoliths, microchemistry, proxy, Cyprinus Carpio. L.