Articles
MODELLING SUNLIGHT INTERCEPTION AND PHOTOSYNTHETIC ACTIVITY-CORRELATION WITH FIELD DATA
Article number
526_40
Pages
365 – 372
Language
Abstract
A theoretical radiation model for the prediction of photosynthetic output was developed.
The model uses radiation interception inside a canopy and predicts hourly and daily photosynthetic rate.
It consists of several semi-empirical equations of which direct and diffuse radiation are the most important.
The model was adapted to field conditions by using measurements of radiation data obtained from vines trained to a slanting trellis with a square transverse section.
This model was calibrated against photosynthesis measured in the field using an ADC-photosynthesis meter.
The curvature of the predicted photosynthesis paralleled the curvature of the measured photosynthesis and a regression with correlation coefficient of 0.9861 and Willmot D-index of 0.9941 was obtained.
Further research is necessary to refine the model for application to different trellising systems, cultivars and environmental conditions.
The model uses radiation interception inside a canopy and predicts hourly and daily photosynthetic rate.
It consists of several semi-empirical equations of which direct and diffuse radiation are the most important.
The model was adapted to field conditions by using measurements of radiation data obtained from vines trained to a slanting trellis with a square transverse section.
This model was calibrated against photosynthesis measured in the field using an ADC-photosynthesis meter.
The curvature of the predicted photosynthesis paralleled the curvature of the measured photosynthesis and a regression with correlation coefficient of 0.9861 and Willmot D-index of 0.9941 was obtained.
Further research is necessary to refine the model for application to different trellising systems, cultivars and environmental conditions.
Authors
P.D. Haasbroek, J. Myburgh, J.J. Hunter
Keywords
Online Articles (54)