Type 4
The watercourse has a low gradient, has average grain size, with the presence of stones and boulders. The water is fresh, generally lightly loaded. The watercourse is often too wide for the riparian areas to be connected. Aggradations form in the bed or at the bottom of the banks and are colonized by herbaceous plants. The watercourse is generally not framed by the hillsides and may present floodable banks.
Connection of riparian areas (if intact): partial or total
Altitude: <100 m (2-72 m)
Watercourse width (low): >20 m
Grain size (banks and bed): Pebbles, stones very present (few boulders), few / no rocks
Gradient: Low to medium: 1.5% (0-3%)
Current:
Usually low to medium
Banks: 24 ° (4 ° -90 °), bank generally extended by a plain
Salinity:
<1 g/L
Ten-year daily rainfall: 175 to 198 mm
Tree species: Andira inermis, Inga ingoides, Lonchocarpus heptaphyllus, Inga laurina, Cordia sulcata, Homalium racemosum, Ceiba pentandra, Citharexylum spinosum*, Margaritaria nobilis, Mangifera indica, Leucaena leucocephala*, Gliricidia sepium, Cocos nucifera. Shrub species: Piper dilatatum (if sufficient humidity), Senna alata, Mimosa pigra. Herbaceous species : Sphagneticola trilobata, Commelina diffusa, Steinchisma laxum, Cyperus involucratus, Cenchrus purpureus, Coix lacryma-jobi. Note: the most downstream parts can be very xerophilic.