During the early 1880s what factor most contributed to the South having an agricultural economy gradpoint

There were many farms in the South, in contrast with the industrialized North. To keep these farms working and operating to the full potential, people used slaves. The slaves would pick the crops and do work.

hope this helps

crop rotation kepy different plants in the soil instead of once constintly. when switching out plants you have different nutrients being absorbed at different speeds and different roots growing differently therfore the spoil and water flow have to adapt and carry fresh nutrients to carry the constant changes that were going on in the soil.