A census
That would be the yield.
The amount of people in a given area, such as the number of people living in Canada is close to 30 million.All of the people inhabiting a specified area.
Pressure describes the amount of force exerted on a given area.
The Amount Of Force
I believe it is called the yield. It is a density problem, m/v were the mass would be the biomass and the v would be the area.
productivity
Birth rate is the amount of baby's per 1000 people living in a given area
pressure
It would be called the "Population Density"
Pressure
Pressure
Pressure