Rarity-weighted Species Richness (Biorarity)
An index of species richness adjusted by rarity, highlighting areas with unique and geographically restricted species distributions.
Description
This indicator provides a global estimate of species richness, weighted by the rarity of each species. It ranges from 0 (low richness) to 100 (high richness). Richness is calculated from probability distributions of thousands of species, representing habitat suitability. These distributions are combined with rarity weights (range-size rarity), giving greater importance to species with restricted geographic ranges.
The underlying data comes from species occurrence records (GBIF) and environmental layers that describe habitat characteristics. This combination allows the indicator to highlight areas of high biodiversity and ecological uniqueness, which are essential for the provision of ecosystem services such as pollination, water regulation, and climate resilience.
What it measures
- Species richness at global scale, adjusted by species rarity.
- Relative contribution of birds, mammals, amphibians, and other taxa.
- Probability-based habitat suitability, weighted by range-size rarity.
How to interpret
- Low values (near 0): Few species, limited rarity.
- High values (closer to 100): High species richness and concentration of rare, geographically restricted taxa.
Unit / Scale
Index (0–100, rarity-weighted).
Author / Source
Lemu (2024)
— built with occurrence data from the Global Biodiversity Information Facility (GBIF) and environmental covariates.
🔗 https://www.gbif.org
Applications in Atlas
- Identification of priority zones for biodiversity conservation.
- Support for land-use planning and sustainable territorial management.
- Definition of land-use compatibility based on ecological value.
- Assessment of ecological vulnerability to land-use change and human pressures.
- Integration into ecosystem service analyses (e.g., pollination, water regulation, climate resilience).