HydroBASINS lev08 watershed · #2080571480
Bassin du Tarn
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 : Aveyron, Tarn
Sub-basin area
218,7km²
Upstream area
3 780,1km²
Discharge
70,63m³/s
Mean elev.
560m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin du Dourdou806 km²
- Bassin du Tarn683 km²
2 dept-equivalent regions (GADM L2)
- 214.0 km²97.6% of basin
- 5.2 km²2.4% of basin
23 communes (GADM L5)Available for FRA, RWA
- Alrance27.80 km²78% commune
- Réquista23.64 km²39% commune
- Lestrade-et-Thouels23.32 km²55% commune
- Villefranche-de-Panat19.22 km²63% commune
- Rebourguil18.03 km²51% commune
- Saint-Izaire17.78 km²51% commune
- Brousse-le-Château14.88 km²100% commune
- Brasc14.28 km²67% commune
- Broquiès12.26 km²32% commune
- Saint-Juéry11.50 km²39% commune
- Montclar10.30 km²79% commune
- Connac9.82 km²96% commune
- Fraissines4.74 km²77% commune
- Vabres-l'Abbaye2.60 km²6% commune
- La Bastide-Solages2.53 km²37% commune
- Le Truel2.10 km²8% commune
- Salles-Curan1.61 km²2% commune
- Calmels-et-le-Viala1.36 km²6% commune
- Durenque0.62 km²2% commune
- Trébas0.46 km²8% commune
- Ayssènes0.18 km²1% commune
- Coupiac0.14 km²1% commune
- Cadix0.00 km²0% commune
2 intersecting protected areas
Grands Causses
IUCN VRegional Nature Park
131.12 km² overlap
Vallée du Tarn (de Brousse jusqu'aux gorges)
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
5.30 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 133 distinct species · 18 990 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 38 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 du Tarn : 36 espèces + 2 bulles famille, 73 interactions GloBI documentées sur 6 types (connectance 10.4%, filtre Serrano α=0.2). Les 2 bulles regroupent des espèces visuellement absorbées par famille (≥3 espèces visibles).
Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).
Hydroclimate (BasinATLAS lev08)
Mean T°
11,6°C
Annual rain
771mm
Moisture idx (CMI)
-0,20
Runoff
467mm/an
PET
963mm
AET
644mm
Mean slope
10,3°
Water table
502cm
Forest
43%
Crops
8%
Urban
0%
Protected
60%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)