oligotrophy (n.)

before vowels olig-, word-forming element meaning "few, the few," from Greek oligos "few, scanty, small, little," in plural, "the few;" a word of uncertain origin.

word-forming element meaning "food, nourishment," from Greek -trophia, from trophe "food, nourishment," related to trephein "make thrive, nourish, rear; to make solid, congeal, thicken."