Respiration is breathing. Breathing produces carbon dioxide. Plants breathe, animals breathe, and organisms in the soil breathe. Plant respiration is estimated as a function of net primary productivity, and a fixed carbon use efficiency (0.5). Animal respiration is based on the sum of animal biomass from people, pets, and wildlife multiplied by an animal respiration rate for mammals. Soil respiration rate is a function of the ecosystem type.
Plant respiration = net primary productivity * carbon use efficiency.
Animal respiration = animal biomass * animal respiration rate.
Soil respiration = area of ecosystems * soil respiration rate density.
Depends upon:
—Parameters: animal respiration rate and soil respiration rate density
—Other metrics: plant growth and wildlife biomass