So with slavery outlawed in an ATL USA would they turn back to indentured service as a way to get the labor necessary to run the big plantations or would the plantations by necessity be split up and shrunk to something more reasonable?
1) What Indentured Servitude was, and is, explained here fairly well:
http://en.wikipedia.org/wiki/Indentured_servant
Why it was what it was is better explained here:
http://eh.net/Clio/Publications/indentured.shtml
2) What happened when it declined (last paragraph)
http://www.africanaonline.com/slavery_introduction.htm
3) Why it was declining:
"1680s – Rising wages in England shrank the pool of poor people willing to gamble on a new life (or an early death) as indentured servants in America. During this time, more black slaves were arriving in America than white servants"
I haven't been able to cross reference this cause elsewhere to any original sources (except JSTOR and most of us don't have access)
But, for purely economical reasons, while Indentured Servitude served (until late 1600's, early 1700's) cheap labor requirements and population replacement purposes, eventually it transformed the labor economy by giving rise to more and more Indenture Completed people who were frustrated at the finite amount of servants arriving, and their own conditions... Given increased economics (wages) in England & Europe, the numbers of servants began to drop as well. When the English Crown lost the sole license of slave trading (and they'd only been importing to Caribbean and S. America), merchants jumped at the opportunity to provide mass quantities of labor, more cheaply than indentureds.
You can try here:
http://www.mrbaker.org/American Life in the 17th Century.htm
and here (for greater detail)
http://chss.montclair.edu/english/furr/spl/thandekawhiting.html
In short, combine a) improving economic conditions b) improving living conditions c) increasing labor crises situations and d) racism to provide a reasonable explanation for the declining population of IS and the rising population of 'Chattel'.
Distasteful subject, and extremely rife with problematic political controversy
However, I did like how one article pointed out that the ration, in ~1640-1650, was 1 to 6... black to white, indentured servants. That, in the labor pool, skin color was truly seen as only skin deep and they 'laughed, worked, stole hogs, got drunk, and even made love together' frequently, as a common occurrence.
A small ray of hope for mankind, yes?