HydroBASINS lev08 watershed · #2080611440
Bassin de Río Cega
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 : Madrid, Segovia, Valladolid
Sub-basin area
2 567,9km²
Upstream area
2 567,9km²
Discharge
5,66m³/s
Mean elev.
929m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 0 basins
Source / headwater (no upstream basin)
3 dept-equivalent regions (GADM L2)
- 2054.3 km²79.9% of basin
- 515.8 km²20.1% of basin
- 1.3 km²0.1% of basin
11 intersecting protected areas
Sierra de Guadarrama
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
338.67 km² overlap
Sierra de Guadarrama - ZEPA
IUCN Not ReportedSpecial Protection Area (Birds Directive)
326.52 km² overlap
Natural Park
297.87 km² overlap
Lagunas de Cantalejo - ZEPA
IUCN Not ReportedSpecial Protection Area (Birds Directive)
113.71 km² overlap
Lagunas de Cantalejo
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
92.15 km² overlap
Sierra de Guadarrama
IUCN IINacional Park
37.30 km² overlap
Salgüeros de Aldeamayor
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
11.82 km² overlap
Riberas del Río Cega
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
5.37 km² overlap
Cuenca del río Lozoya y Sierra Norte
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.70 km² overlap
2 more protected areassorted by overlap area
Riberas del Río Duero y afluentes
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.03 km² overlap
Cueva de los Murciélagos
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.01 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
3 394 distinct species · 167 094 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 33 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 Río Cega : 22 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 74 interactions GloBI sur 4 types (connectance 14.0%, 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°
11,4°C
Annual rain
457mm
Moisture idx (CMI)
-0,55
Runoff
72mm/an
PET
1 015mm
AET
392mm
Mean slope
2,3°
Water table
528cm
Forest
29%
Crops
39%
Urban
0%
Protected
13%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)