Biology – Biodiversity | e-Consult

Biodiversity, or biological diversity, is a complex concept that can be assessed at multiple levels. These levels provide a comprehensive understanding of the variety of life on Earth. The primary levels of assessment are:

• Ecosystem and Habitat Diversity: This level focuses on the variety of different ecosystems and habitats present in a given area. It considers the range of environments, such as forests, grasslands, wetlands, coral reefs, and deserts. Measuring this involves mapping and categorizing these habitats. For example, a landscape with a mix of woodland, farmland, and a river system would have high ecosystem diversity. Remote sensing techniques (satellite imagery) and ground surveys are used to assess this. The number of distinct habitat types is a key metric.
• Species Diversity: This level examines the number of different species present within a particular ecosystem or habitat. It's often measured using species richness (the total number of species) and species evenness (the relative abundance of each species). A high species richness and evenness indicate high species diversity. Methods include conducting surveys (e.g., transect walks, quadrats), DNA barcoding, and analyzing existing ecological records. The Shannon-Wiener index is a common measure of species diversity, taking both richness and evenness into account.
• Genetic Diversity: This level focuses on the variation in genes within a single species. It's crucial for a species' ability to adapt to changing environmental conditions. Genetic diversity can be assessed by analyzing DNA samples from a population. Techniques include analyzing allele frequencies, measuring heterozygosity, and using microsatellite markers. Low genetic diversity makes a species more vulnerable to disease and environmental changes. Conservation efforts often aim to maintain or increase genetic diversity within populations.

These levels are interconnected. For instance, high ecosystem diversity often supports high species diversity, which in turn contributes to genetic diversity within species.