HydroBASINS lev08 watershed · #2080022370
Bassin de Canal de Lanchères
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 : Seine-Maritime, Somme
Sub-basin area
92,9km²
Upstream area
92,9km²
Discharge
1,74m³/s
Mean elev.
19m
Administrative coverage
2 dept-equivalent regions (GADM L2)
- 85.8 km²92.0% of basin
- 0.0 km²0.0% of basin
12 communes (GADM L5)Available for FRA, RWA
- Cayeux-sur-Mer28.16 km²100% commune
- Woignarue13.40 km²80% commune
- Lanchères12.69 km²73% commune
- Pendé7.85 km²45% commune
- Saint-Valery-sur-Somme6.13 km²48% commune
- Ault5.97 km²100% commune
- Brutelles3.89 km²64% commune
- Friaucourt3.09 km²76% commune
- Mers-les-Bains2.50 km²46% commune
- Saint-Quentin-la-Motte-Croix-au-2.08 km²31% commune
- Le Tréport0.02 km²0% commune
- Ponthoile0.00 km²0% commune
13 intersecting protected areas
Regional Nature Park
79.95 km² overlap
Baie de Somme
IUCN Not ReportedWetland of International Importance (Ramsar Site)
33.45 km² overlap
Estuaires et littoral picards (baies de Somme et d'Authie)
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
22.78 km² overlap
Marine Nature Park
15.96 km² overlap
Biotope Protection Order
2.53 km² overlap
Hable d\'ault
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
2.14 km² overlap
Falaises et bois du rompval
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.70 km² overlap
Hâble D\'Ault
IUCN IVBiotope Protection Order
0.67 km² overlap
Le bois houdant
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.22 km² overlap
4 more protected areassorted by overlap area
Baie De Somme
IUCN IVNational Nature Reserve
0.09 km² overlap
Baie de Somme
IUCN Not ReportedMarine Protected Area (OSPAR)
0.08 km² overlap
Pointe du hourdel
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.01 km² overlap
Rencloture de la gaite
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 563 distinct species · 79 013 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 34 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 Lanchères : 28 espèces reliées par 76 interactions GloBI sur 5 types (connectance 12.8%, filtre Serrano α=0.2). 7 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°
10,6°C
Annual rain
644mm
Moisture idx (CMI)
-0,10
Runoff
587mm/an
PET
718mm
AET
507mm
Mean slope
0,9°
Water table
55cm
Forest
1%
Crops
59%
Urban
1%
Protected
16%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)