Brett A Melbourne & Paul J Daniel (2003)

A low-cost sensor for measuring spatio-temporal variation of light intensity on the stream bed

Journal of the North American Benthological Society 22(1): 143-151

Key words: light sensor, photosynthetically active radiation, measurement, streams, amplifier circuit


We describe a low-cost sensor for measuring light intensity on the stream bed that is simple and quick to construct. We also describe an amplifier circuit for use with the sensors. The sensor consists of a photodiode and diffuser encased in heatshrink tubing. The sensor had acceptable spectral and cosine responses, a good linear relationship with a Li-Cor Quantum sensor, and withstood the rigors of the stream-bed environment. The low cost of the sensor makes it suitable for studies of spatio-temporal variation, where many sensors are required.