HydroBASINS lev08 watershed · #5080130980
Bassin de Sungai Asahan
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 4 administrative regions : Asahan, Lake Toba, Tapanuli Utara, Toba Samosir
Sub-basin area
1 167,9km²
Upstream area
4 302,2km²
Discharge
157,39m³/s
Mean elev.
887m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de Binanga Mual1416 km²
- Bassin · #5080132430844 km²
4 dept-equivalent regions (GADM L2)
- 828.0 km²71.2% of basin
- 231.7 km²19.9% of basin
- Lake Toba86.0 km²7.4% of basin
- 17.0 km²1.5% of basin
1 intersecting protected areas
Dolok Surungan
IUCN IVWildlife Reserve
34.08 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
357 distinct species · 652 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 Sungai Asahan : 29 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 36 interactions GloBI sur 5 types (connectance 6.1%, filtre Serrano α=0.2). 6 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°
21,9°C
Annual rain
2 208mm
Moisture idx (CMI)
0,30
Runoff
1 255mm/an
PET
1 540mm
AET
1 491mm
Mean slope
7,8°
Water table
264cm
Forest
38%
Crops
30%
Urban
10%
Protected
3%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)