Final answer:
A pyramid of biomass represents the total amount of living matter at each trophic level, while a pyramid of productivity represents the rate of energy or biomass production. Both types of pyramids are usually pyramid-shaped due to the flow of energy and biomass in an ecosystem.
Step-by-step explanation:
A pyramid of biomass represents the total amount of living matter (biomass) at each trophic level in an ecosystem. It shows the biomass decreasing as you move up the food chain, with the largest amount of biomass at the bottom with the producers. A pyramid of productivity, on the other hand, represents the rate at which energy or biomass is produced in an ecosystem. It shows the productivity increasing as you move up the food chain, with the highest productivity at the top with the apex predators.
The pyramid of biomass is typically pyramid-shaped because the energy is transferred and lost as you move up the food chain. As a result, there is less biomass available at higher trophic levels compared to lower trophic levels. The units for a pyramid of biomass are usually grams per square meter or kilograms per hectare, representing the mass of living organisms in a given area.
The pyramid of productivity is also usually pyramid-shaped because the energy flow follows the same pattern as the biomass pyramid. The units for a pyramid of productivity are typically grams per square meter per year or kilograms per hectare per year, representing the amount of biomass produced in a given area over a specific time period.