A model for nutrient and water flow and their uptake by plants grown in a soilless culture

Research output: Contribution to journalArticlepeer-review

40 Scopus citations

Abstract

The objective of this study was to develop a sensitive means of control to optimize nutrient concentrations in the root zone of a soilless system, considering plant water and nutrient uptake, and solution circulation rates. A model is proposed to simulate ornamental plants' growth in a channel with a non-interacting soilless substrate, irrigated by point sources with constant discharge rates, spaced uniformly along the channel. The model accounts for compensation for transpiration water losses and consequent salinity buildup, and its interactions with plant growth and nutrient uptake. The added water may contain given concentrations of nutrients and/or toxic (saline) compounds, which would cause salinity buildup. Uptake of each solute is specific, according to a Michaelis-Menten kinetics mechanism, but passive uptake by the transpiration stream is also accounted for. Plant growth is affected by time/age and ionic balance in the solution. The model was calibrated with lettuce (Lactuca sativa L.) plants grown in volcanic ash. Simulation of potassium concentration change as a result of discharge rate and emitter spacing revealed that the two parameters could compensate one for the other, once a target lower limit is set. Potassium appeared to be most sensitive to sodium accumulation in the growth medium; this accumulation changed ionic concentration balance, which affected pH and bicarbonate concentration. Passive uptake of calcium by the transpiration stream is highly affected by the root fraction involved, but its calculated contribution is below published values is highly affected by the root fraction involved, but its calculated contribution is below published values.

Original languageEnglish
Pages (from-to)309-319
Number of pages11
JournalPlant and Soil
Volume271
Issue number1-2
DOIs
StatePublished - 1 Apr 2005

Keywords

  • Ion influx mechanisms
  • Lettuce (Lactuca sativa L.)
  • Nutrient uptake
  • Recycled nutrient solution
  • Salinity buildup
  • Soilless culture

ASJC Scopus subject areas

  • Soil Science
  • Plant Science

Fingerprint

Dive into the research topics of 'A model for nutrient and water flow and their uptake by plants grown in a soilless culture'. Together they form a unique fingerprint.

Cite this