/* sheep.
Data on sheep and grass for eco system 
Alan Bundy 21.5.81 */

/* External Variables */
external_variable(light).
external_variable(temperature).


/* Parameters of sheep component */
parameter(rate_of_grazing(sheep),'1.25').
parameter(rate_of_defecation(sheep),'0.56').
parameter(specific_rate_of_respiration(sheep),'0.5').

/* State variables of sheep component */
state_variable(biomass(sheep),initial,'7.3').

/* Internal variables of sheep component */
internal_variable(biomass_respiration(sheep), '1.0'-'0.05'*temperature).

/* Processes affecting biomass of sheep component */
process(biomass(sheep),grazing(sheep)).
process(biomass(sheep),-defecation(sheep)).
process(biomass(sheep),-respiration(sheep)).

/* Parameters of grass component */
parameter(specific_rate_of_photosynthesis(grass),'0.53').
parameter(specific_rate_of_respiration(grass),'0.27').

/* State variable of grass component */
state_variable(biomass(grass),initial,'35.2').

/* Internal variables of grass component */
internal_variable(biomass_photosynthesis(grass),'1.0'+'0.03'*light+'0.005'*light^2).
internal_variable(biomass_respiration(grass),'1.0'+'0.03'*temperature).

/* Processes affecting biomass state variable of grass component */
process(biomass(grass),growth(grass)).
process(biomass(grass),-grazing(grass)).


/* Ecological Knowledge */
animal(sheep).
vegetable(grass).
grazes_on(sheep,grass).



