Alpha diversity refers to the diversity of species within a particular habitat or ecosystem. It is a measure of the number and abundance of different species present in a specific area. Alpha diversity can be calculated using various indices, such as the Shannon-Wiener index or Simpson's index.

Beta diversity, on the other hand, is a measure of species turnover between different habitats or ecosystems. It quantifies the differences in species composition between two or more habitats. Beta diversity is important because it provides insights into the heterogeneity and uniqueness of different ecosystems.

Large genetic diversity within a population is significant for several reasons. Firstly, it enhances the population's ability to adapt and respond to environmental changes, such as climate change or the introduction of new diseases. Genetic diversity provides a wider range of traits and variations, increasing the chances of some individuals having advantageous characteristics that enable them to survive and reproduce.

Secondly, genetic diversity helps to prevent inbreeding and the associated negative effects of reduced genetic variation, such as decreased fertility and increased susceptibility to diseases. Inbreeding depression can lead to decreased population fitness and viability.

Lastly, genetic diversity is crucial for the long-term survival of a population. It provides the raw material for evolution and allows for the potential emergence of new traits or adaptations over time. Without genetic diversity, populations become more vulnerable to extinction as they lack the ability to respond to changing environments or threats.

In summary, alpha and beta diversity provide measures of species richness and composition within and between ecosystems, respectively. Large genetic diversity within a population is essential for its adaptability, resilience, and long-term survival.