Which describes an effect of spanish and portuguese exploration to the new world on the populations of native civilizations in the 16th century?

A description would be enslavement and ultimate death. The Spanish and Portuguese saw themselves as superior to these native civilizations, thus killing off most of them. 

The statistics for the eastern war are grim. more than three-million men died in the fighting, more than nine-million men were wounded, and every major country which participated lost its form of government.