the coastal and marine zone of rio de janeiro is not just the ocean and its immediate coast, but the entire interface region between the state's land and the ocean, which is comprised of many different types of terrain and bodies of water, all supporting an incredible array of native species of flora and fauna.

the various ecosystems of the coastal zone include, sandy beaches, such as the iconic copacabana beach and ipanema beach, mangroves, such as those that hem the sepetiba bay, coastal lagoons, such as the water sporting hub of lagoa rodrigo de freitas or the eye-catching pools of região dos lagos, coral reefs off the coast of the ocean, and rocky shores, amongst various others.

the biological richness of the state's coastal zone is down to a combination of factors. firstly there is a high concentration of nutrients within the waters, including varying salinity. to add to this there are various different temperature gradients, as well as ample opportunities for shelter or support for the species.