HydroBASINS lev08 watershed · #4080558110
Bassin de 小百川
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 : Nikkō, Shioya
Sub-basin area
191,5km²
Upstream area
799,6km²
Discharge
19,54m³/s
Mean elev.
662m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de 鬼怒川319 km²
- Bassin de 男鹿川289 km²
2 dept-equivalent regions (GADM L2)
- 174.0 km²90.8% of basin
- 17.5 km²9.2% of basin
7 intersecting protected areas
Nikko
IUCN VNational Park
77.49 km² overlap
Green Corridor
54.68 km² overlap
Kobyaku shogakko
IUCN IVPrefectural Wildlife Protection Area
0.24 km² overlap
National Natural Monument
0.12 km² overlap
Takaharayama Iramomi
IUCN IVRare Population Protected Forest
0.06 km² overlap
Shojinsawa
IUCN IVBiocenosis Protected Forest
0.02 km² overlap
Funyu nishi shogakko
IUCN IVPrefectural Wildlife Protection Area
0.02 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
494 distinct species · 1 015 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 35 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 小百川 : 31 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 39 interactions GloBI sur 5 types (connectance 6.6%, filtre Serrano α=0.2). 4 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°
9,9°C
Annual rain
1 845mm
Moisture idx (CMI)
0,50
Runoff
714mm/an
PET
905mm
AET
903mm
Mean slope
14,7°
Water table
367cm
Forest
75%
Crops
17%
Urban
8%
Protected
40%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)