Ontologia

Ruisseau· 12 segments

L'Aa

Crosses 1 administrative regions : Pas-de-Calais

ruisseau

Total length

55km

Max discharge

7,8m³/s

Max Strahler

3

Segments matched

12

River geography1 admin regions · 33 communes

Parent watershed

hybas-2080022540934 km²

1 administrative regions crossed (GADM L2)

33 communes (L5)

14 intersecting protected areas

5 more protected areas

1 page = 1 named river (aggregation of 12 HydroRIVERS v10 segments). Spatial join cached after first hit.

Species present

551 distinct species · 2 528 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).

RègnesAnimalPlanteChampignonBacterie
RelationsPredationParasitismeSymbiosePollinisation
StatutEn dangerVulnérableProtégéeEndémique

Indicateurs du tissu écologique

Tissu écologique de L'Aa : 25 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 103 interactions GloBI sur 5 types (connectance 17.3%, filtre Serrano α=0.2). 10 bulles taxonomiques (cascade genre/famille GloBI, ≥3 espèces).

Espèces affichées
35
Interactions affichées
103
Connectance
0.173
Patrimoniales
1
Plus dense que (national)0 %(top 100%)

Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).

Hydrology (HydroRIVERS v10)

Total length

55km

Max discharge

7,8m³/s

Max Strahler

3

Segments matched

12

HydroRIVERS v1.0 (Lehner et al. 2019) aggregated by name + main_riv → 1 entity = 1 named river.