FREQUENCY RESPONSE OF A MARINE ECOSYSTEM 



35 



T 1 r 



0.1 CO CO 10 - 



(a) 



n 1 r 



0.1 CO CO 10 CO 



< 



□c 



LU 

 D 



I 10 

 < 



10^ 

 10" 

 10" 



1 10 



(b) 



< 4 



Q. 



T1 — n 



(c) 



— n — *" 



0.5 I 5 I 



1 10 



10' 



10^ 



1 — \ — r 



io""-i — |— 



2 5 10 



-4 



FREQUENCY, cycles/year 



-| — I — r 



2 5 10 



(d) 



Fig. 7 Bode amplitude and phase plots generated by cross-spectral 

 analysis of an input and a response, (a) Plots from a hypothetical 

 second-order linear system, oj^ ^nd <;" can be estimated graphically, 

 (b) Plots of Narragansett Bay ammonia vs. cell abundance, (c) Plots 

 of Narragansett Bay solar radiation vs. cell abundance, (d) Plots of 

 microcosm 2 ammonia vs. chlorophyll. 



