Alpha diversity

Alpha diversity is the mean species diversity found within a site at a local scale, essentially a measure of how many different species live in a given local area. The ecologist R. H. Whittaker introduced the concept together with two related measures, beta and gamma diversity, forming a single framework for describing biodiversity at different spatial scales. In this framework, the total species diversity across a landscape, gamma diversity, results from combining the average local diversity captured by alpha diversity with the amount of variation between different sites, captured by beta diversity, letting ecologists break overall biodiversity down into distinct, measurable components.