HydroBASINS lev08 watershed · #2080572450
Bassin de la Douze
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 : Landes
Sub-basin area
298km²
Upstream area
1 161,4km²
Discharge
15,17m³/s
Mean elev.
95m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de la Douze443 km²
- Bassin de l'Estampon421 km²
1 dept-equivalent regions (GADM L2)
- 298.6 km²100.0% of basin
19 communes (GADM L5)Available for FRA, RWA
- Lencouacq55.75 km²56% commune
- Saint-Avit35.78 km²87% commune
- Cachen35.03 km²98% commune
- Arue31.52 km²64% commune
- Pouydesseaux26.98 km²80% commune
- Canenx-et-Réaut25.40 km²89% commune
- Lucbardez-et-Bargues21.52 km²99% commune
- Bélis15.40 km²77% commune
- Maillères14.05 km²92% commune
- Mont-de-Marsan9.42 km²26% commune
- Sarbazan7.31 km²33% commune
- Bostens6.61 km²87% commune
- Roquefort6.46 km²53% commune
- Le Sen4.19 km²8% commune
- Cère0.99 km²2% commune
- Lacquy0.97 km²5% commune
- Gaillères0.54 km²4% commune
- Saint-Justin0.44 km²1% commune
- Retjons0.26 km²0% commune
4 intersecting protected areas
Landes De Gascogne
IUCN VRegional Nature Park
181.16 km² overlap
Réseau hydrographique des affluents de la Midouze
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
12.16 km² overlap
Champ de tir du Poteau
IUCN Not ReportedSpecial Protection Area (Birds Directive)
0.15 km² overlap
Vallon Du Cros
IUCN IVBiotope Protection Order
0.06 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 579 distinct species · 74 231 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 39 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 la Douze : 27 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 120 interactions GloBI sur 6 types (connectance 14.6%, filtre Serrano α=0.2). 14 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°
12,5°C
Annual rain
974mm
Moisture idx (CMI)
-0,03
Runoff
473mm/an
PET
1 001mm
AET
718mm
Mean slope
1,1°
Water table
127cm
Forest
96%
Crops
1%
Urban
2%
Protected
20%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)