For photochemical smog to form, VOCs must be present. In order to create photochemical smog, bond(s) with nitrogen oxide, and therefore the nitrogen oxide is no longer available to combine with .

The rate that would change would be the  searching efficiency/attack rate. there are only two other rates in this model: the  growth rate of prey, and the  predator or consumer mortality rate.the  searching efficiency/attack rate is what indicates how effectively can a predator capture its prey whether in the searching process or actual capturing/attacking process. 

Sorry  i don't understand can you rephrase that