Dynamic behavior of CO2 uptake as affected by light: system identification based on spectral analysis

Summary The dynamic behavior of CO₂ uptake in sunflower plants was measured in a computer controlled apparatus and identified systematically using spectral analysis.To obtain impulse responses of net CO₂ uptake, power spectra were estimated by the Fast Fourier Transform (FFT) method. FFT was done by computing 512 separate data points sampled at one minute intervals. From examination of coherency, it was determined that dynamic behavior of CO₂ uptake could be estimated by linear filtering based on impulse response as affected by the light in changes slower than 0.08 cycle min^-1. This suggests that other dynamic phenomena in physiological ecology could be estimated effectively by using advanced system theory involving many algorithms.