Figure 8. Energetics model of Hillsborough County natural system illustrating 

 the translation of the model into differential equation form. 



where 



E = 



N = 



j = 



J = 



r 



J = 







J = 

 J = 







•J = 



(ki-ko)J N-k-,N-k.N = differential equation for N 

 ^ 1 2 r 3 4 ^ 



Energy source (solar, rain, and wind) 



natural biomass 



energy flow coefficients 



inflow of energy (solar insolation) 



energy not used (albedo) 



energy absorbed by system (absorbed insolation) 



J + J = conservation of energy 

 r 



k J N 

 r 



J + k NJ 

 r or 



(k^M<2) jf^=k M_k N 

 1+k N ^ ^ 



292 



