To investigate the genetic effects on the population of Coreius guichenoti of dam constructions in the upper reaches of the Yangtze River, we analyzed the genetic diversity and population structure of 12 populations collected in 2009 and 2019 using mitochondrial DNA (mtDNA) control regions. There was no significant difference in genetic diversity between 2009 and 2019 (P > 0.05), but the population structure tended to become stronger. Genetic differentiation (FST) among five populations (LX, BB, YB, SF and JA) collected in 2009 was not significant (P > 0.05). However, some populations collected in 2019 were significantly differentiated (P < 0.05), indicating that the population structure has undergone change. A correlation analysis showed that the genetic diversity of the seven populations collected in 2019 was significantly negatively correlated with geographical height (r = −0.808, P = 0.028), indicating that the populations at high elevations were more vulnerable than those at low elevations. In order to prevent the further decrease of genetic diversity and population resources, some conservation and restoration suggestions, such as fish passage and artificial breeding, are put forward.
Genetic diversity and phylogeography of
Daphnia similoides sinensis
located in the middle and lower reaches of the Yangtze River