HydroBASINS lev08 watershed · #2080545620
Bassin du Lignon
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 3 administrative regions : Ardèche, Haute-Loire, Loire
Sub-basin area
711,4km²
Upstream area
711,4km²
Discharge
8,11m³/s
Mean elev.
988m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 0 basins
Source / headwater (no upstream basin)
3 dept-equivalent regions (GADM L2)
- 663.1 km²93.0% of basin
- 33.3 km²4.7% of basin
- 16.6 km²2.3% of basin
44 communes (GADM L5)Available for FRA, RWA
- Tence52.41 km²100% commune
- Riotord49.72 km²96% commune
- Yssingeaux48.59 km²60% commune
- Mazet-Saint-Voy45.81 km²100% commune
- Le Chambon-sur-Lignon41.89 km²100% commune
- Montregard40.37 km²100% commune
- Dunières34.31 km²100% commune
- Saint-Jeures34.29 km²100% commune
- Lapte31.91 km²100% commune
- Araules31.71 km²100% commune
- Saint-Julien-Molhesabate26.26 km²95% commune
- Saint-Pal-de-Mons22.86 km²82% commune
- Grazac21.48 km²100% commune
- Raucoules21.04 km²100% commune
- Les Vastres18.56 km²61% commune
- Chaudeyrolles17.19 km²92% commune
- Saint-Régis-du-Coin15.37 km²74% commune
- Champclause14.75 km²67% commune
- Chenereilles14.32 km²100% commune
- Sainte-Sigolène13.78 km²45% commune
- Saint-Maurice-de-Lignon13.60 km²46% commune
- Fay-sur-Lignon13.27 km²100% commune
- Devesset12.98 km²43% commune
- Le Mas-de-Tence12.49 km²100% commune
- Saint-Front10.62 km²20% commune
- Mars9.08 km²48% commune
- Les Villettes8.49 km²73% commune
- Saint-André-en-Vivarais8.07 km²40% commune
- Saint-Bonnet-le-Froid8.01 km²59% commune
- Saint-Romain-Lachalm6.36 km²33% commune
- Montfaucon-en-Velay4.74 km²100% commune
- Monistrol-sur-Loire3.04 km²6% commune
- Saint-Agrève1.82 km²4% commune
- Saint-Clément1.16 km²6% commune
- Les Estables0.97 km²3% commune
- Marlhes0.59 km²2% commune
- La Versanne0.35 km²2% commune
- Saint-Genest-Malifaux0.28 km²1% commune
- Queyrières0.25 km²2% commune
- La Rochette0.09 km²1% commune
- Vanosc0.09 km²0% commune
- Montusclat0.03 km²0% commune
- Saint-Sauveur-en-Rue0.02 km²0% commune
- Burdignes0.02 km²0% commune
11 intersecting protected areas
Monts D\'Ardèche
IUCN VRegional Nature Park
44.44 km² overlap
Gorges de la Loire
IUCN Not ReportedSpecial Protection Area (Birds Directive)
41.47 km² overlap
Pilat
IUCN VRegional Nature Park
16.62 km² overlap
Mézenc
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
14.65 km² overlap
Haute vallée du Lignon
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
8.11 km² overlap
Le Mezenc
IUCN IVForest Managed Biological Reserve
1.80 km² overlap
Tourbières du Pilat et landes de Chaussitre
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.87 km² overlap
Sucs du Velay / Meygal
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.37 km² overlap
sources du gournier
IUCN IVLand acquired by a regional conservatory of natural areas
0.06 km² overlap
2 more protected areassorted by overlap area
Secteur des Sucs
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.05 km² overlap
Chaussitre Et Gimel
IUCN IVForest Managed Biological Reserve
0.04 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
4 798 distinct species · 373 626 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 41 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 Lignon : 7 espèces reliées par 310 interactions GloBI sur 6 types (connectance 13.6%, filtre Serrano α=0.2). 61 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°
7,6°C
Annual rain
855mm
Moisture idx (CMI)
0,08
Runoff
373mm/an
PET
780mm
AET
643mm
Mean slope
6,6°
Water table
445cm
Forest
79%
Crops
5%
Urban
1%
Protected
3%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)