Zonation (Ecol.). An arrangement of different plant communities in more or less definite zone, following one another in a constant order due to a continuous change in the habitat factors.

Zone (Ecol.). (a) One of the belts occupied by successive communities in a Zonation, (b) Soil See under Soil horizons.

Zone of Saturation (Ped.). The zone occupied by the ground water in the soil. See Water Table.

Zygote (Genet.). The cell formed by the sexual fusion of two Gametes. also the organism developing from such a cell BCFT..