Based on the data shown in the graph, which of the following best describes how ecologists could determine when this ecosystem is approaching a climax community?
A
Determine if the keystone species in the ecosystem is present two years after the volcanic eruption
B
Measure the biomass of the pioneer species present before and after the volcanic eruption
(C
Record the number and type of producers present every year after the eruption
D
Calculate the net primary productivity of a specific indicator species every year after the eruption

Scientists can tell that an ecosystem's climax is approaching when they record the number and type of producers present each year after the eruption, as shown in option C.

We can arrive at this answer because:

An ecological community reaches its climax when it reaches its last stage of ecological succession.

At this stage, animals and plants are well developed and interact in a balanced way.

Thus, the ecological region must have a considerably high number of producers, as it shows that the basis for interactions between living beings is well established.

Thus, scientists must observe the number of producers that settle in each ecological succession, to be able to determine when the community is close to its climax.

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