HydroBASINS lev08 watershed · #2080487590
Bassin de Canal de Nantes à Brest - L'Oust Canalisé
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 : Morbihan
Sub-basin area
220,3km²
Upstream area
2 083,5km²
Discharge
39,75m³/s
Mean elev.
68m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
26 communes (GADM L5)Available for FRA, RWA
- Caro37.72 km²99% commune
- Ruffiac34.03 km²92% commune
- Sérent23.17 km²38% commune
- La Chapelle-Caro16.66 km²100% commune
- Missiriac13.78 km²100% commune
- Lizio11.80 km²69% commune
- Ploërmel11.52 km²22% commune
- Le Roc-Saint-André9.75 km²98% commune
- Saint-Congard8.56 km²39% commune
- Réminiac8.32 km²70% commune
- Monterrein7.08 km²100% commune
- Saint-Marcel6.78 km²52% commune
- Saint-Abraham6.53 km²100% commune
- Malestroit4.92 km²83% commune
- Saint-Servant4.59 km²20% commune
- Saint-Laurent-sur-Oust3.85 km²100% commune
- Augan2.94 km²7% commune
- Montertelot2.38 km²100% commune
- Saint-Martin-sur-Oust2.20 km²8% commune
- Pleucadeuc1.49 km²4% commune
- Tréal1.16 km²6% commune
- Saint-Nicolas-du-Tertre0.76 km²6% commune
- Quily0.72 km²14% commune
- Cruguel0.20 km²1% commune
- Guégon0.06 km²0% commune
- Guillac0.02 km²0% commune
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
1 424 distinct species · 17 300 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 30 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 Canal de Nantes à Brest - L'Oust Canalisé : 18 espèces reliées par 98 interactions GloBI sur 6 types (connectance 17.5%, filtre Serrano α=0.2). 16 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°
11,2°C
Annual rain
800mm
Moisture idx (CMI)
0,06
Runoff
565mm/an
PET
754mm
AET
560mm
Mean slope
2,5°
Water table
187cm
Forest
0%
Crops
71%
Urban
0%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)