HydroBASINS lev08 watershed · #2080587480
Bassin de Fiume Orcia
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 : Grosseto, Siena
Sub-basin area
879,8km²
Upstream area
879,8km²
Discharge
9,56m³/s
Mean elev.
441m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 0 basins
Source / headwater (no upstream basin)
2 dept-equivalent regions (GADM L2)
- 671.5 km²76.2% of basin
- 209.8 km²23.8% of basin
17 intersecting protected areas
Crete dell'Orcia e del Formone
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
81.40 km² overlap
Crete dell'Orcia e del Formone
IUCN Not ReportedSpecial Protection Area (Birds Directive)
81.40 km² overlap
Cono vulcanico del Monte Amiata
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
31.78 km² overlap
Monte Labbro e alta valle dell'Albegna
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
14.62 km² overlap
Monte Labbro e alta valle dell'Albegna
IUCN Not ReportedSpecial Protection Area (Birds Directive)
14.62 km² overlap
Lucciolabella
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
14.17 km² overlap
Lucciolabella
IUCN Not ReportedSpecial Protection Area (Birds Directive)
14.17 km² overlap
Regional/Provincial Nature Reserve
11.78 km² overlap
Ripa d'Orcia
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
8.30 km² overlap
8 more protected areassorted by overlap area
Monte Cetona
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
6.22 km² overlap
Regional/Provincial Nature Reserve
5.72 km² overlap
Monte Oliveto Maggiore e Crete di Asciano
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
5.26 km² overlap
Monte Oliveto Maggiore e Crete di Asciano
IUCN Not ReportedSpecial Protection Area (Birds Directive)
5.26 km² overlap
Regional/Provincial Nature Reserve
5.21 km² overlap
Regional/Provincial Nature Reserve
3.45 km² overlap
Regional/Provincial Nature Reserve
2.74 km² overlap
Regional/Provincial Nature Reserve
0.22 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
3 100 distinct species · 29 408 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 de Fiume Orcia : 30 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 119 interactions GloBI sur 5 types (connectance 13.2%, filtre Serrano α=0.2). 13 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°
12,8°C
Annual rain
695mm
Moisture idx (CMI)
-0,25
Runoff
342mm/an
PET
928mm
AET
583mm
Mean slope
7,5°
Water table
299cm
Forest
28%
Crops
49%
Urban
0%
Protected
3%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)