HydroBASINS lev08 watershed · #2080018840
Bassin de Rio Ota
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 7 administrative regions : Alenquer, Arruda dos Vinhos, Azambuja, Cadaval, Sobral de Monte Agraço +2
Sub-basin area
543,9km²
Upstream area
70 756km²
Discharge
424,31m³/s
Mean elev.
109m
Administrative coverage
Hydrographic chain
▼ Drains into
Outlet (drains to ocean / endorheic)
▲ Receives from 3 basins
- Bassin de Rio Maior901 km²
- Bassin de Ribeira de Magos257 km²
- Bassin de Rio do Olho92 km²
7 dept-equivalent regions (GADM L2)
- 288.5 km²53.0% of basin
- Vila Franca de XiraLisboa · Portugal95.9 km²17.6% of basin
- AzambujaLisboa · Portugal84.6 km²15.5% of basin
- Arruda dos VinhosLisboa · Portugal49.4 km²9.1% of basin
- Sobral de Monte AgraçoLisboa · Portugal19.5 km²3.6% of basin
- CadavalLisboa · Portugal5.1 km²0.9% of basin
- Torres VedrasLisboa · Portugal1.3 km²0.2% of basin
5 intersecting protected areas
Serra de Montejunto
IUCN VProtected Landscape
18.78 km² overlap
Estuário do Tejo
IUCN Not ReportedSpecial Protection Area (Birds Directive)
14.97 km² overlap
Estuário do Tejo
IUCN Not ReportedSite of Community Importance (Habitats Directive)
14.81 km² overlap
Serra de Montejunto
IUCN Not ReportedSite of Community Importance (Habitats Directive)
14.69 km² overlap
Local Natural Monument
3.16 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 179 distinct species · 39 230 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 37 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 Rio Ota : 26 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 100 interactions GloBI sur 5 types (connectance 15.0%, filtre Serrano α=0.2). 11 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°
15,9°C
Annual rain
722mm
Moisture idx (CMI)
-0,24
Runoff
353mm/an
PET
953mm
AET
573mm
Mean slope
4,4°
Water table
213cm
Forest
30%
Crops
37%
Urban
6%
Protected
3%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)