How does the amount of biomass at the fourth trophic level compare to the amount of biomass at the third trophic level immediately below it?

Answer 1

Biomass at the fourth trophic level is approximately ten times smaller than biomass at the third trophic level.

Answer 2

There is a detailed explanation at the link from which this quote comes:

In general, only about 10% of the energy consumed by one level is available to the next. For example, If hares consumed 1000 kcal of plant energy, they might only be able to form 100 kcal of new hare tissue. For the hare population to be in steady state (neither increasing nor decreasing), each year's consumption of hares by foxes should roughly equal each year's production of new hare biomass. So the foxes consume about 100 kcal of hare biomass, and convert perhaps 10 kcal into new fox biomass.

Answer 3

Generally, the rule of ten percent applies where 10 percent of the energy in a particular trophic level moves to the next trophic level. The rest of the energy goes towards movement, maintenance, reproduction and respiration. The population levels however are much more difficult to predict and are usually determined via research on a specific group of organisms and can vary due to the effects of predation, parasitism, and environmental constraints of each organism. Biomass is also difficult to predict and usually must be determined experimentally.

Answer 4

Trophic Level (Bottom Up)

-Detritivore

-Photoautotroph

-Herbivore

-Carnivore

Think of the trophic levels as a pyramid with the detritivore utilizing the largest (base level) energy store. The next level are the photoautotrophs. They feed off the available nutrients that have been broken down products of the detritivores. And so on and so on all way to carnivores. Notice if you were to draw this out it would resemble a stair stepped pyramid. It looks like a pyramid because the energy consumed from the lower trophic level is not completely utilized by the organisims of the next higher level.

Now when relating this to the biomass of an organism and it's ecology, it sort of makes sence that the number of individuals will be proportional to their food source, right? It's biomass is dependant on the way it interacts with its environment. Form dictates function.

EX: The polar bear utilizes the highest (and smallest) trophic level in Antarctica. Because of the limited resource, the bear needs to occupys a vast territory in order to survive. It is a large animal (i.e. high biomass) because it needs to maintain its body heat when looking for prey. That also augments it's need for a large territiory. I hope this cleared up what you wanted.

Answer 5

Energy attracts production in a food chain

Answer 6

Each trophic level contains one-tenth as much biomass as the level below it and ten times as much biomass as the level above it.

Answer 7

ask your teacher in Biology