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Designing hydroponic systems: The importance of flow rate

  Added by: MR_NATURAL420  Last edited by: MR_NATURAL420  Viewed: 672 times   Rated by 17 users: 6.67/10
Most hydroponic systems have inadequate flow rates, which results in reduced oxygen levels at root surfaces. This stresses roots and can increase the incidence of disease. Oxygen is soluble only as a micronutrient, yet its uptake rate is much faster than any other nutrient element.
The nutrient film technique was designed to improve aeration of the nutrient solution because of the thin film of solution, but the slow flow rates in NFT cause channeling of the solution and reduced flow to areas with dense roots. The root surfaces in these areas become anaerobic, which diminishes root respiration, reduces nutrient uptake, increases N losses via denitrification, and makes roots susceptible to infection.
  Last modified: 02:00 - May 01, 2001 
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