The Collaborative International Dictionary of English v.0.48:

Depauperate \De*pau"per*ate\, v. t. & i. [imp. & p. p.
   Depauperated; p. pr. & vb. n. Depauperating.] [LL.
   depauperatus, p. p. depauperare to impoverish; L. de- +
   pauperare to make poor, pauper poor.]
   To make poor; to impoverish.
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         Liming does not depauperate; the ground will last long,
         and bear large grain.                    --Mortimer.
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         Humility of mind which depauperates the spirit. --Jer.
                                                  Taylor.
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