Development of Data Acquisition Model for Daily Light Integral Measurement

Anton Louise P. de Ocampo


Daily Light Integral or DLI is the measure of the amount of Photosynthetic Photon Flux (PPF) that is received by plants throughout the day. This measurement is accounted for because there exists a relationship between the maximum yield and the amount of light the crops received. Knowing that the available sunlight is not enough, augmentation through the use of artificial lighting can be done. The aim of this study is to design a data acquisition model and implement it in an ATMega 5260 to measure the everyday DLI. Transducers were characterized to give accurate conversion of the solar irradiance incident to the sensors to variations on resistance. This characterization was done by comparing the actual measurements of solar illumination to characteristics described in the datasheet of the transducer. The Daily Light Integral was then calculated using the Planck’s distributions as well as the photon energy content of the Photo-synthetically Active Radiation (PAR). The developed instrument successfully logged a 24-hr measurement of the PPF and DLI on 2 different days. The results were verified using the method for estimating DLI as suggested in a study of Dr. Morgan (2013). A low-cost transducer can be accurately used to provide reliable measurements of Daily Light Integral provided that the model used for calculating the parameters are correct


artificial lightning; Daily Light Integral; Photo-synthetically Active Radiation; Light requirements of plants; Photon Flux

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