Complex sentence: The soil was depleted by imbalanced fertilizing, and the productivity reduced further by improper tillage where the weeds are not permitted to grow, therefore inhibit it to tap the buffer available in the subsoil.
Split into simpler sentences: The soil was depleted by imbalanced fertilizing and productivity was reduced further by improper tillage. Weeds are not permitted to grow, therefore inhibiting the buffer available in the subsoil.