The soils were formed under periodic flood conditions that explain their hydromorph characteristics where gley soils predominate.
Temporal and spatial alterations of the hydrological regime led to very different soil groups:
-alluvial soils with various salinity degrees existed along the embankments;
-initial fluviatile soils with low salinity were present on the embankments in the center of the islands;
-gley soils and peaty gley soils existed in the lower areas with temporary inundation;
-moderately calacarious-limnic soils were formed ay the bottom of the permanent lakes and others waters.
The nutrient cycling of nitrogen, carbon and phosphorous occurs in the soils as well as the retention and adsorption of C, N, P, K, s through clay minerals and humic acids.
SOURCE : IBIS TOURS BIRD-WATCHING SPECIALISTS