How can a small biomass of producers support a larger biomass of consumers?

1 Answer
Oct 10, 2017

Total biomass is important

Explanation:

A sheep on average eats around 3% of its body weight in DM (dry matter) per day. If you say one sheep weighs 50 kg, so that means on average each would eat between 1500 g of DM per day. If there is 120 g of DM in a square meter of a field, then each sheep would need 12.5 square meters of grazing per day to sustain itself. If you picture that amount, pace out 3.1 m by 4 m.

The key terms in here is renewal time. A sheep can live 8 years or so (if you allow of course). One sheep can produce one new sheep in a year. A grass renewes itself in a couple of weeks. As long as you do not eradicate grasses with chemicals or other means.

In two weeks a sheep can return the first area (it consumes or grazes). Thererefore, total area to support one sheep is #14times12.5 = 175# square meters.