FREQUENCY RESPONSE OF A MARINE ECOSYSTEM 



33 



6000 



4800 



3600 - 



T 



20 30 



FREQUENCY, cycles/year 



(b) 



r 



40 



T 



50 



Fig. 6 Variance spectra, with 95% confidence interval, for ammonia 

 (a) and chlorophyll (b) in microcosm 2. Each spectral estimate is 

 smoothed over three adjacent frequency bands. B = 4.21 cycles/year. 

 These are similar to spectra for other sewage treatment replicates. 

 Spectra for control replicates were much less peaked. 



