Record substrate moisture, irrigation timing, root-zone temperature, drainage behavior, root appearance, and plant demand together.
Visual lesson 06
Root-zone oxygen diffusion
Compare air-filled and water-filled pore space to understand why oxygen replenishment can become limiting when media remains saturated and root or microbial respiration continues.
Root-zone gas exchange
Interactive concept mapPore space controls how quickly oxygen can be replaced
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Air-filled pores
Connected air spaces allow comparatively rapid diffusion between the atmosphere and the root zone.
A wet root zone is not automatically hypoxic, but persistent saturation increases the risk that oxygen supply cannot keep pace with respiration.
Knowledge check
PracticeCan you explain what the visual is showing?
Why can a persistently saturated root zone reduce oxygen availability around roots even when the irrigation water itself contains dissolved oxygen?
Track this lesson
Mark the lesson complete when you are comfortable with the visual, observations, and system context.
Evidence & further reading
Sources connected to this lesson
These references support specific biological, diagnostic, environmental, or process concepts used in this lesson. They are not a substitute for crop-specific testing or local regulatory guidance.Foundational angiosperm root-hair development, absorptive surface, nutrient acquisition, environmental response, and root–microbe interaction.
Cannabis photosynthetic and stomatal responses to water deficit, genotype-dependent drought response, biomass partitioning, and physiological interpretation under measured conditions.
Cannabis gas exchange, photosynthesis, transpiration, stomatal conductance, PPFD, temperature, and carbon-dioxide response under measured conditions.
System context