8.5 Community Ecology

The structure of a community is defined by its species composition and species diversity. Species composition refers to the types of species present in a community, while species diversity accounts for both the variety of species and their relative abundances. One way to quantify species diversity is through Simpson's Diversity Index. This index is calculated using the formula: Here, n represents the total number of organisms of a particular species, and N is the total number of organisms of all species. Sigma indicates a summation of all of ${(\frac{n}{N})^2}$.A higher diversity index indicates greater species diversity, reflecting a healthier and more stable ecosystem.