43 on the middle portion of the lake, dramatic changes have occurred. The western portion transformed into a shallow and temporal lake where full inundations seem to occur on a decadal basis. Currently, Cuitzeo displays a salinity gradient ranging from fresh (ca. 700 μS cm−1) east portion to a saline (up to ca. 13 000 μS cm−1), soda-alkaline (Na2CO3 > NaCl, Na2SO4 > KCl) west basin (Alcocer & Hammer, 1999).