Tuesday, 24 June 2014

Monoculture and entropy - Hadrian's Wall



These fields are near Harlow Hill on the Hadrian's Wall. The top two pictures show the monoculture wheat. Very uniform so I'd argue low entropy. The field edge in the bottom picture shows what it should be like with a rough mixture. The Second Law of Thermodynamics says that you can only go from lower total entropy to higher total entropy. So the change that made the field have a lower entropy must have resulted in a raising of the entropy elsewhere in the Universe. The entropy is lowered in the field by the use of herbicides to remove the other competing plants. But this may also remove the natural predators of the pest species that might eat the wheat, so pesticides need to be used as well. So where is the increase in entropy? I need to think about that.