Table 3 continued.






Fish production is a function of
radiation and the amount of land
surface covered by water. Depen-
dence on two or more such factors
is demonstrated by the work gate.
When the action appears multipli-
cative, the work gate is a simple
multiplier function.





Fish density is fish biomass di-
vided by water surface area, de-
noted by a divider work gate. As
surface water area shrinks, fish
density increases, its limit im-
posed by minimum water area and
maximum fish biomass.