Note on the distribution of crustaceans in floodplain ponds in the Ciuc Basin (Romania) and implications foe habitat restoration

In the Ciuc Basin, Olt river was regulated and the old riverbed was filled in the late 1970s and early 1980s. There are few published data on the habitat changes caused by these works. I studied the distribution of two large branchiopods (Chirocephalus shadini and Lynceus brachyurus) and a calanoid copepod (Hemidiaptomus amblyodon) in ponds of riverbed and non-riverbed origin. I found that these species occur more frequently in non-riverbed ponds and the density of C. shadini was 3.6 times larger on average in non-riverbed ponds than in riverbed ponds. I conclude that these organisms could be used as indicators in reconstituting the small-scale habitat structure of the floodplain before the river regulation.