Question

Can a species diversity increase or decrease after a fire on a grassland

Answer 1

Species diversity refers to the number of different species in a community or ecosystem. So for example if you have an ecosystem and there are all different areas of that system like water, trees, and ground levels. obviously monkeys do not live in the water so, if you were to affect the water it would more than likely not affect the monkeys directly even though that water IS part of their ecosystem, but it will affect the other animals, living in that water. so if you were to take out a species in that water you are taking away a part of that ecosystem that makes it diverse. To answer your question, yes the species diversity can decrease after a fire on a grassland.

Answer 2

The species diversity would decrease after a fire on a grassland. Every organism has a particular genotype. Typically, as the population increases, so does a population's and species's  diversity because of the greater diversity of the allele frequency. In events such as fires, you are removing organisms from the population which causes a less diverse allele frequency.