PREDICTIVE CONTROL OF CONCENTRATION OF NUTRIENT SOLUTION ACCORDING TO INTEGRATED SOLAR RADIATION DURING ONE HOUR IN THE MORNING

The amount and the concentration of nutrient solution in growing plants by way of hydroponics are closely related to not only the kinds of plants and their development stages but also climatic conditions.
Irrigation system controlled by the time clock is not so efficient to maintain proper water and nutrient supply in the root zone since it is difficult to keep the balanced proportion of nutrients in the solution.
The irrigation should vary depending upon climatic conditions, especially solar radiation.
Data has been collected that can help predicting the concentration of nutrient solution with respect to solar radiation for one hour duration in the morning.
An attempt has been made to develop a computerized irrigation system which can control nutrient concentration depending upon daily integrated solar radiation and the development stages of cucumber plants.

The predicted daily integrated solar radiation was similar to the actual one.
In addition, little difference was observed between the predicted nutrient concentration by the computer system and the measured one.
Therefore, it is possible to control the nutrient concentration based on integrated solar radiation for one hour duration in the morning.
This is effective in maintaining the water and nutrients balance in the root zone.

International Symposium on Plant Production in Closed Ecosystems

M.Y. Roh, Y.B. Lee

computerized irrigation, hydroponics, nutrient concentration, root zone, solar radiation

https://doi.org/10.17660/ActaHortic.1996.440.45