What is the main reason the Southern economy was dependent on slave labor?

Southern economy was dependent on slave labour because they grew labour intensive cash crops.The south was mainly dependent on agriculture and farming as the main economy,and to maintain large plantation and fields slave labour was needed.  

Explanation:

as the maasai legends tell, "in the beginning of the world, enkai was the only god: the guardian of rain, fertility, sun, and love. with that love, enkai birthed three sons." solución