What term describes the variety of different species within a specific ecosystem?

The term that describes the variety of different species within a specific ecosystem is biological diversity. This concept encompasses not only the number of species present but also their abundance and the ecological roles they play within that ecosystem. Biological diversity is essential for ecosystem stability, resilience, and the provision of ecosystem services, such as pollination, nutrient cycling, and habitat provision.

In contrast, population density refers to the number of individuals of a particular species within a defined area, which does not capture the variety of species present. Species uniformity would imply a lack of diversity, suggesting that many individuals belong to the same species, and therefore does not reflect the variety sought in the question. Genetic homogeneity indicates a lack of genetic diversity within a species, which can make populations more susceptible to diseases and changes in the environment, but again, this does not address the variety of different species in an ecosystem.