Based on the data shown in the graph, when would the species richness of the ecosystem have been the lowest?

Graphs can be used to represent real life situations.

The richness of the ecosystem is at the lowest in 1993, which is 3 years after the year of eruption.

From the graph (see attachment), we have the lowest point on the graph as:

This means that the richness is at the lowest in 1993

Also, from the graph, we have the year of eruption to be:

The difference between the year of eruption and the lowest point on the graph is:

This means that the richness is at the lowest three years after the year of eruption.

Read more about graph interpretation at:

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Hello. The graph to which this question refers, shows that after a volcanic eruption there is a decrease in the number of species of plants and animals in the region, in between this number begins to grow as time progresses.

According to the data, the species richness in an ecosystem is lower one year after the volcanic eruption.

Explanation:

The volcanic eruption has the capacity to decimate many species of plants, as well as species of animals, which decreases the richness of species in this ecosystem. However, the year following the volcanic eruption presents an even smaller species risk, since many species are unable to readapt to the new environment, thus undergoing a process of natural selection. As this adaptation progresses, the number of species will grow periodically, making the species richness greater in the ecosystem in four years.