The local species pool is known as alpha diversity. It is also the diversity present within the community. Beta diversity is the diversity present between the communities. The diversity present in the ranges of communities is known as Gamma diversity.

Introduction:
Alpha diversity is a measure of biodiversity that focuses on the diversity within a particular community or ecosystem. It provides information about the number of species and their relative abundance within a defined area. Alpha diversity is a fundamental concept in ecology and is often used to assess the health and functioning of ecosystems. In this question, we are asked to identify which level of diversity is described by alpha diversity.

Intra community diversity:
The correct answer is option B, intra community diversity. Intra community diversity refers to the diversity within a particular community or ecosystem. It measures the variety of species and their relative abundance within a given area. It is a measure of the richness and evenness of species within a community. Intra community diversity can be assessed using various metrics, such as species richness and the Shannon diversity index.

Diversity within biomes:
Option A, diversity within biomes, is not an accurate description of alpha diversity. Biomes are large-scale ecological regions characterized by distinct climate, vegetation, and animal life. Alpha diversity focuses on the diversity within a specific community or ecosystem, rather than the diversity within a larger biome.

Inter community diversity:
Option C, inter community diversity, is also not an accurate description of alpha diversity. Inter community diversity refers to the diversity between different communities or ecosystems. It compares the species composition and abundance across multiple communities. Alpha diversity, on the other hand, focuses on the diversity within a single community or ecosystem.

Diversity within a species population:
Option D, diversity within a species population, is not an accurate description of alpha diversity. Alpha diversity measures the diversity of species within a community or ecosystem, rather than within a single species population. It provides information about the variety and abundance of different species within a given area, rather than focusing on the genetic diversity within a single species population.

Conclusion:
In summary, alpha diversity describes the diversity within a particular community or ecosystem. It measures the richness and evenness of species within a given area and provides valuable information about the health and functioning of ecosystems. Alpha diversity is an important concept in ecology and is often used to assess the impact of environmental changes on biodiversity.