Coco Coir and Hydroponic Cultivation Glossary A Technical Reference for Hydroponic Production in Controlled Environment Agriculture Aeration The presence and movement of air within the substrate root zone. Aeration is governed by air filled porosity and pore structure and is essential for oxygen diffusion to roots. Inadequate aeration leads to reduced root respiration, impaired nutrient uptake, and increased susceptibility to root pathogens. Air Filled...