HydroBASINS lev08 watershed · #4081146090
Bassin de Vellar River
A watershed (drainage basin) is not a body of water — it is the land area where rainfall converges towards a single river that eventually reaches the sea (or an endorheic basin). Boundaries follow ridgelines.
Crosses 2 administrative regions : Cuddalore, Perambalur
Sub-basin area
116,4km²
Upstream area
2 991,9km²
Discharge
13,07m³/s
Mean elev.
82m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de Vellar1831 km²
- Bassin · #40811459801045 km²
2 dept-equivalent regions (GADM L2)
- Cuddalore88.4 km²76.3% of basin
- Perambalur27.5 km²23.7% of basin
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
131 distinct species · 884 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 33 species (selected proportionally per kingdom among those with at least one documented interaction here) to keep the graph readable. Hover for details, click to explore the full ecosystem of a species.
ℹ️ The territory contains many more species than displayed and all their documented interactions: the graph is intentionally the structural skeleton (top-N species by composite local score, edges filtered by Serrano 2009 disparity filter α=0.2).
Indicateurs du tissu écologique
Tissu écologique de Bassin de Vellar River : 25 espèces dont 3 patrimoniales (LR IUCN CR/EN/VU) reliées par 41 interactions GloBI sur 3 types (connectance 7.8%, filtre Serrano α=0.2). 8 bulles taxonomiques (cascade genre/famille GloBI, ≥3 espèces).
Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).
Hydroclimate (BasinATLAS lev08)
Mean T°
28,7°C
Annual rain
994mm
Moisture idx (CMI)
-0,44
Runoff
201mm/an
PET
1 765mm
AET
839mm
Mean slope
0,2°
Water table
28cm
Forest
20%
Crops
68%
Urban
17%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)