HydroBASINS lev08 watershed · #4080049560
Bassin de Yan Oya
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 14 administrative regions : Dambulla, Galenbindunuwewa, Gomarankadawala, Hingurakgoda, Horowpothana +9
Sub-basin area
1 661km²
Upstream area
1 661,6km²
Discharge
24,51m³/s
Mean elev.
92m
Administrative coverage
14 dept-equivalent regions (GADM L2)
- 643.0 km²38.9% of basin
- 214.2 km²12.9% of basin
- 193.4 km²11.7% of basin
- 147.6 km²8.9% of basin
- 79.2 km²4.8% of basin
- 75.7 km²4.6% of basin
- 52.6 km²3.2% of basin
- 52.4 km²3.2% of basin
18 intersecting protected areas
Paddawiya
IUCN IbReserved Forest
107.70 km² overlap
Pamburugashinna
IUCN IbReserved Forest
96.34 km² overlap
Hurulu Forest Reserve
IUCN Not ApplicableUNESCO-MAB Biosphere Reserve
61.56 km² overlap
Hurulu/Konwewa
IUCN IbReserved Forest
54.08 km² overlap
Sigiriya
IUCN IVSanctuary
27.25 km² overlap
Reserved Forest
25.33 km² overlap
Simbillakanda
IUCN IbReserved Forest
17.07 km² overlap
Hurulu
IUCN IaConservation Forest
16.19 km² overlap
Nambakada Forest
IUCN IbReserved Forest
8.63 km² overlap
9 more protected areassorted by overlap area
Kokebe
IUCN IbReserved Forest
6.79 km² overlap
Tumbikulama
IUCN IbReserved Forest
5.42 km² overlap
Unagollewa
IUCN IbReserved Forest
4.63 km² overlap
Kantalai
IUCN IbReserved Forest
4.25 km² overlap
Thananparichchan
IUCN IbReserved Forest
3.46 km² overlap
Talapathkanda
IUCN IbReserved Forest
1.47 km² overlap
Moragaswewa
IUCN IbReserved Forest
0.80 km² overlap
Angunawelapelessa
IUCN IbReserved Forest
0.47 km² overlap
Inamaluwa
IUCN IbReserved Forest
0.16 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
508 distinct species · 13 349 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 27 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 Yan Oya : 23 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 24 interactions GloBI sur 3 types (connectance 6.8%, 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°
27,3°C
Annual rain
1 553mm
Moisture idx (CMI)
0,01
Runoff
509mm/an
PET
1 534mm
AET
1 046mm
Mean slope
1,2°
Water table
72cm
Forest
44%
Crops
15%
Urban
0%
Protected
6%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)