Descripción: UNEP Protected Areas Programme.
«Sian Ka'an lies on a partially emerged coastal limestone plain which forms part of the extensive barrier reef system along the eastern coast of Central America. Much of the reserve lies in a zone of recent Pleistocene origin which still appears to be in a transitional stage. A large series of sink holes (cenotes) exist in the area and are characteristic features of the Yucatan and Florida peninsulas. The hydrological cycle is complex and the water table is permanently close to the surface (never deeper than 8m). Asa result, each year during the dry season, about 20% of the terrestrial part of the reserve remains flooded. This figure increases to about 75% by the end of the rainy season.»
