418 



J. L. Tiwari et al. 



where 



y 502 = concentration of R-DOC in the water column, and 

 z = depth of pond as a function of time, mimics the average 

 pond water level and changes seasonally. 

 = 16+4 sin [(2 tt/ .000349) + 1 .5708] . 



This function was used to simulate the amount of light in the model 

 for algal photosynthesis. Later, real incident radiation data were used to 

 validate the empirical results using the periodic light generator. 



Similarly, another empirical function was developed from available 

 temperature data to introduce temperature differences into the model: 



r= 1 2 sin [( TT/— 480 w) / 2400j 



(9) 



TABLE 1 0- 1 State Variables of the Benthic Model 



Symbol 



Description 



Initial values 

 (mgCm ') 



.Xi Benthic surface algal biomass 



^2 Benthic buried algal biomass 



Xi Benthic total algal biomass = x\-\- Xz 



X\o\ Benthic bacterial biomass 



X201 Benthic ciliate biomass 



X20-1 Benthic micrometazoan biomass 



AT 203 Benthic flagellate biomass 



X301 New litter (first year dead vascular plants) 



-^401 

 X402 



JC5OI 

 Xh02 



Benthic detritus 



Inert particulate carbon 



Benthic useful dissolved organic carbon 

 Benthic refractory dissolved organic carbon 



JC602 Benthic CO 2 



Xgoi Benthic chironomid larvae, cohort I beginning at 530 hr 



Xmi Benthic chironomid larvae, cohort 2 



jr803 Benthic chironomid larval biomass, cohort 3 



X804 Benthic chironomid larval biomass, cohort 4 



jcsos Total benthic chironomid larvae biomass = j:8oi+jc802+X803+jc804 



-^806 X\ +X2+JC 101 +^201 "("JC202+JC203+.X401 



JCSOT (X ik Wk) -^ (X 101 ^805) +(X' 201X806) + 

 {X 20lk 807 ) + (X 203K 808) + (X 401 A; 8O9) 



X1401 Benthic detrital phosphorus (mg P m '^) 



Xisoi Benthic colloidal phosphorus (mg P m "*) 



X1601 Benthic phosphate phosphorus (mg P m '') 



40.0 



80.0 



120.0 



350.0 



1.0 



30.0 



40.0 



80000.0 



500.0 

 1700000.0 



4.0 

 1240.0 



0.0 



144.0 

 70.0 

 56.0 

 70.0 



0.0 



0.0 

 0.04 



