HydroBASINS lev08 watershed · #2080049930
Bassin de Gwendraeth Fawr
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 : Carmarthenshire, NA
Sub-basin area
296,8km²
Upstream area
296,8km²
Discharge
6,49m³/s
Mean elev.
84m
Administrative coverage
2 dept-equivalent regions (GADM L2)
- Carmarthenshire285.9 km²95.9% of basin
- NA4.5 km²1.5% of basin
30 intersecting protected areas
Carmarthen Bay and Estuaries/ Bae Caerfyrddin ac Aberoedd
IUCN Not ReportedEmerald Network
18.35 km² overlap
Site of Special Scientific Interest
15.44 km² overlap
Carmarthen Bay and Estuaries / Bae Caerfyrddin ac Aberoedd
IUCN Not ReportedMarine Protected Area (OSPAR)
10.05 km² overlap
Burry Inlet
IUCN Not ReportedEmerald Network
7.94 km² overlap
Burry Inlet
IUCN Not ReportedWetland of International Importance (Ramsar Site)
7.87 km² overlap
Site of Special Scientific Interest
4.88 km² overlap
Burry Inlet
IUCN Not ReportedMarine Protected Area (OSPAR)
4.31 km² overlap
Carmarthen Bay Dunes/ Twyni Bae Caerfyrddin
IUCN Not ReportedEmerald Network
2.64 km² overlap
Pembrey Burrows And Saltings
IUCN Not ReportedLocal Nature Reserve
2.51 km² overlap
21 more protected areassorted by overlap area
Afon Tywi
IUCN IVSite of Special Scientific Interest
1.74 km² overlap
Mynydd Llangyndeyrn
IUCN IVSite of Special Scientific Interest
0.85 km² overlap
Cernydd Carmel
IUCN IVSite of Special Scientific Interest
0.76 km² overlap
Cernydd Carmel
IUCN Not ReportedEmerald Network
0.76 km² overlap
Gwernydd Pembre
IUCN IVSite of Special Scientific Interest
0.49 km² overlap
Coedydd Capel Dyddgen
IUCN IVSite of Special Scientific Interest
0.25 km² overlap
Coedydd Y Garn
IUCN IVSite of Special Scientific Interest
0.23 km² overlap
Coed Gwempa
IUCN IVSite of Special Scientific Interest
0.18 km² overlap
Ynys Uchaf
IUCN IVSite of Special Scientific Interest
0.16 km² overlap
Morfa Berwig
IUCN Not ReportedLocal Nature Reserve
0.13 km² overlap
Glan-Yr-Afon
IUCN Not ReportedLocal Nature Reserve
0.13 km² overlap
Ashpits Pond - Pwll Lagoon
IUCN Not ReportedLocal Nature Reserve
0.12 km² overlap
Site of Special Scientific Interest
0.09 km² overlap
Cwm Clydach, Cydweli
IUCN IVSite of Special Scientific Interest
0.08 km² overlap
Site of Special Scientific Interest
0.06 km² overlap
Gwel y Coed
IUCN IVSite of Special Scientific Interest
0.06 km² overlap
Waun-Fawr
IUCN IVSite of Special Scientific Interest
0.06 km² overlap
Caeau Rhyd-Y-Gwiail
IUCN IVSite of Special Scientific Interest
0.05 km² overlap
Pwll Lagoon
IUCN IVSite of Special Scientific Interest
0.05 km² overlap
North Dock Dunes
IUCN Not ReportedLocal Nature Reserve
0.04 km² overlap
Llyn Llech Owain
IUCN IVSite of Special Scientific Interest
0.03 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
7 927 distinct species · 179 092 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 37 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 Gwendraeth Fawr : 28 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 74 interactions GloBI sur 5 types (connectance 11.1%, filtre Serrano α=0.2). 9 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°
10,1°C
Annual rain
1 107mm
Moisture idx (CMI)
0,46
Runoff
1 060mm/an
PET
592mm
AET
528mm
Mean slope
3,6°
Water table
206cm
Forest
6%
Crops
15%
Urban
14%
Protected
9%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)