• Atolls database

  • Biogeochemical data into the water column

  • Morphometric data

• Numerical analysis

  • methods

  • variables

  • analysis

• Models

Table 1 – Forced variables (VFs)

(these values are given in the database)

1- SLag or LagArea 

Area of the lagoon in ha.

2- Por

Porosity, : the ratio between the linear aperture onto the ocean (hoas + immersed ring + passes) and the total perimeter of the atoll. This value ranges between 0 and 1.

3- Depth

Mean depth in m.

4- Shape

A shape index based on the ratio between the area and the square of the perimeter, multiplied by 2p. This gives a value of 1 for a perfectly circular atoll and a value tending towards 0 for atolls with oblong or complex shapes.

5- Lat

Latitude

6- Long

Longitude

7-LogArea

Log of the Area

8-Log Por

Log of the Porosity

9- RingArea

Area in ha of the coral ring, the emergent part of the atoll.

Tab. 2 – The  internal variables (IVs) relating to the water column

(the 28 IVs recorded can be consulted in the database)   

Sal

Salinity per thousand

NH₄

Dissolved ammonium (µmol NH₄ . l^-1)

NO_2-3

Dissolved nitrates + dissolved nitrites(µmol NO₂ + NO₃.l^-1)

PO₄

Dissolved phosphates (µmol PO₄.l^-1)

POC

Particulate organic carbon (µg C.l^-1)

Chla 

Total chlorophyll (µg Chl.l^-1)

Prod/Chla

Primary production/Chlorophyll a (g C.g Chl^-1.h^-1)

N Bact.

Bacterial levels (10⁶. ml^-1)

Prod/Bact.

Bacterial cell production / bacterial cell biomass (10^-3.h^-1)

Tab. 3 – Internal variables relating to the sediments, fish and benthos mentioned on this page

%C

organic carbon present in the sediment (% weight)

C/N

carbon to  nitrogen ratio in the sediment in moles

Macrophytes

Mean biomass of the macrophytes in g  dry weight /m² 

Coral

Abundance of coral/5m²

Mollusca

Abundance of mollusca/5m²

Echinodermata

Abundance of echinodermata/5m²

Fish

Total mass of fish in g/m²

Piscivores

Contribution of piscivorous fish to the biomass in g/m²

Herbivores

Contribution of herbivorous fish to the biomass in g/m²

Carnivores

Contribution of carnivorous fish to the biomass in g/m²

Planktonophages

Contribution of planktonophages to the biomass in g/m²

Corallivores

Contribution of corralivorous fish to the biomass in g/m²

Detritivores

Contribution of detritivorous fish to the biomass in g/m²