As part of the UTOPIAN project, a data acquisition spanning from September 2021 to December 2021 has allowed for the evaluation the reef flat of Saint-Pierre, Reunion Island. The CORRAM method (COral Reef Rapid Assessment Method) was used, which involves estimating 8 Benthic Biodiversity Indicators (BBIs) composition through circular plots (coral cover, percentage of the genus Acropora within coral communities, algal cover, opportunistic species cover, structural complexity, diameter of the coral colony, coral state of health, density of coral juveniles), and the sedimentation. More than 750 circular plots have been assessed through snorkeling.

For each BBIs, a formula normalization and standardization was use to have a score between 0 and 3 (the value estimated in situ is the colonne with “Nb” and the colonne without “Nb” is the score). With the normalization, we calculated 3 indexes :

1. “Structure” : mean of live coral cover ("Rec_coral"), percentage of Acropora genus with coral community ("Acrop"), complexity structral ("Compl_stru) and diameter of coral colonie ("Taille_cor");
2. “Vitalite” : mean of 
3. “BENTH_DUR” : the mean of all BBIs score.

In parallele we have 10 abiotic environmental variables rank in 3 categories :  

• Geomorphology : bathymetry (from Hyscore project) - proximity to river, and reef crest (were acquired by calculating the 1/distance from each circular plot, using Qgis)
• Watershed variables : proximity to sewage pollution inputs (were acquired by calculating the 1/distance from each circular plot to the wasterwater discharge), the siltation of terrigenous input (collected in situ we the BBIs), and stress linked to turbidity (water samples collected within 170 stations across the reef)
• Physico-chemical parameters (temperature, salinity, pH, and dissolved oxygen (water samples evaluated in situ with a multi-parameter probe - YSE Professional Plus - within 170 stations across the reef)

The 170 stations was interpolated with ordinary kriging analysis and the predict values was excerpt to each circular plot.

So, we have 10 abiotic environmental variables values to each circular plot. 

Futhermore, we have information such as : date, latitude, longitude (EPSG : 32740), habitats, Observator