HydroBASINS lev08 watershed · #2080570680
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 1 administrative regions : Aveyron
Sub-basin area
683,4km²
Upstream area
2 755,9km²
Discharge
52,93m³/s
Mean elev.
666m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de la Dourbie664 km²
- Bassin du Tarn240 km²
33 communes (GADM L5)Available for FRA, RWA
- Saint-Georges-de-Luzençon48.41 km²100% commune
- Millau48.17 km²28% commune
- Castelnau-Pégayrols46.66 km²87% commune
- Saint-Rome-de-Tarn45.80 km²88% commune
- Salles-Curan39.70 km²40% commune
- Viala-du-Tarn37.97 km²100% commune
- Saint-Rome-de-Cernon37.90 km²100% commune
- Montjaux31.69 km²100% commune
- Creissels28.66 km²100% commune
- Saint-Beauzély27.80 km²89% commune
- La Cavalerie26.41 km²65% commune
- Saint-Léons25.55 km²78% commune
- Le Truel24.34 km²92% commune
- Sainte-Eulalie-de-Cernon24.25 km²52% commune
- Ayssènes23.15 km²99% commune
- Lapanouse-de-Cernon22.86 km²100% commune
- Broquiès21.27 km²56% commune
- La Bastide-Pradines20.55 km²100% commune
- Saint-Victor-et-Melvieu18.07 km²100% commune
- Saint-Laurent-de-Lévézou12.11 km²52% commune
- Roquefort-sur-Soulzon11.98 km²72% commune
- Viala-du-Pas-de-Jaux11.63 km²60% commune
- Comprégnac11.02 km²100% commune
- Les Costes-Gozon10.61 km²53% commune
- Villefranche-de-Panat8.51 km²28% commune
- Tournemire8.44 km²100% commune
- Saint-Affrique6.56 km²6% commune
- Saint-Jean-et-Saint-Paul2.24 km²6% commune
- Nant1.31 km²1% commune
- Vézins-de-Lévézou1.02 km²1% commune
- Verrières0.14 km²0% commune
- Lestrade-et-Thouels0.01 km²0% commune
- Curan0.00 km²0% commune
10 intersecting protected areas
Grands Causses
IUCN VRegional Nature Park
636.78 km² overlap
Vallée du Tarn (de Brousse jusqu'aux gorges)
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
31.75 km² overlap
Gorges de la Dourbie et causses avoisinants
IUCN Not ReportedSpecial Protection Area (Birds Directive)
27.87 km² overlap
Devèzes de Lapanouse et du Viala-du-Pas-de-Jaux
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
15.09 km² overlap
Cirques de Saint-Paul-des-Fonts et de Tournemire
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
4.35 km² overlap
Cirque et grotte du Boundoulaou
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
2.23 km² overlap
Serre de Cougouille
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
1.68 km² overlap
Chaos ruiniforme du Rajal Del Gorp
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
1.05 km² overlap
Tourbières du Lévezou
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.97 km² overlap
1 more protected areassorted by overlap area
Grotte Du Boundoulaou
IUCN IVBiotope Protection Order
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
6 877 distinct species · 230 807 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 31 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 : 19 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 109 interactions GloBI sur 6 types (connectance 19.4%, filtre Serrano α=0.2). 15 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°
11,3°C
Annual rain
761mm
Moisture idx (CMI)
-0,20
Runoff
534mm/an
PET
958mm
AET
636mm
Mean slope
9,5°
Water table
412cm
Forest
35%
Crops
25%
Urban
1%
Protected
93%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)