Copper Stress Causes Shell Morphology Changes in Early Juvenile Anodonta woodiana Based on Geometric-Morphometric Analysis.

In this study, the morphological characteristics of early juvenile shells of Anodonta woodiana, which were exposed to different concentrations of aqueous copper, were analyzed using 10 landmarks to determine morphological changes in the shells. Morphological changes mainly occurred at the top of the shell and front and back ends of the central axis. Stepwise discriminant analysis proved shape differences among experimental and control groups. The results of this study demonstrate for the first time that environmentally relevant copper concentrations cause stress-related morphological changes in A. woodiana in the vulnerable early juvenile stage.

Multi-mineral fingerprinting analysis of the Chinese mitten crab (Eriocheir sinensis) in Yangcheng Lake during the year-round culture period.

Chinese mitten crabs (Eriocheir sinensis), originating from Yangcheng Lake, are valuable aquatic products in China. To characterize changes in nutrients in this species in Yangcheng Lake during the year-round culture period, the contents of ten mineral elements in the third pereiopod were evaluated. Principal component analysis revealed that mineral elements changed substantially in the first three months. Thereafter, the elemental "fingerprint" stabilized, and samples could not be accurately distinguished. This pattern was supported by linear discriminant analysis and self-organizing map analysis. These results demonstrate that a long period of time is required for element characteristics to stabilize, suggesting that short-term breeding is insufficient to obtain the natural elemental "fingerprint." In addition, our findings provide a basis for verifying the origin of Chinese mitten crab and other aquatic taxa in Yangcheng Lake.