Ontologia

Municipality · NLD

Alkmaar

Netherlands

CfbTemperate, no dry season, warm summer(100 %)

Species observed

5 141

Observations

297 665

Area

117,8km²

Ecological tissue

Sample of 41 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 Alkmaar : 35 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 108 interactions GloBI sur 5 types (connectance 12.5%, filtre Serrano α=0.2). 7 bulles taxonomiques (cascade genre/famille GloBI, ≥3 espèces).

Espèces affichées
42
Interactions affichées
108
Connectance
0.125
Patrimoniales
1
Plus dense que (national)0 %(top 100%)

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

Species present

5 141 distinct species · 297 665 observations

Source: GBIF Occurrence snapshot 2026-05-01.

Densité d'observations

297 665 obs · 3 cellules
Obs. / cellule
≥ 248 207
248 207–248 206
248 207–248 206
26 673–248 206
< 26 673

Source : GBIF — observations agrégées par hexagones 0.027° × 0.027° (~22km), filtre précision coordonnée < 10 km. Fond carte : OpenFreeMap · © OpenStreetMap.

Climate

Mean T°

10,2°C

Annual rain

922mm

Warmest m°

19,6°C

Coldest m°

1,8°C

Elevation: -3 m on average (min -4 m, max 2 m)

Bioclimatic detailsExpert
Annual mean temp.
10,2°C
Annual rain
922mm
Warmest month
19,6°C
Coldest month
1,8°C
Mean alt.
-3m
Min
-4m
Max
2m
Std. dev.
2m
Köppen-Geiger (dominant)
CfbTemperate, no dry season, warm summer(100 %)Temperate

CHELSA BIO 1-19 v2.1 · ETOPO DEM 60s · Köppen-Geiger 1991-2020 (Beck et al. 2018)

Soil & lithology

pH H₂O

6,7

Org. C

68,8g/kg

Clay

32,3%

Sand

26,0%

Silt

41,6%

Average over 0-30 cm. Per-depth details in expert panel.

Dominant lithology: suGLiM

3 soil depths detailedExpert
0–5 cm
pH H₂O
6,6
Org. C
81,5g/kg
Clay
31,3%
Sand
26,8%
Silt
41,9%
5–15 cm
pH H₂O
6,8
Org. C
51,6g/kg
Clay
32,5%
Sand
26,2%
Silt
41,3%
15–30 cm
pH H₂O
6,8
Org. C
73,3g/kg
Clay
33,2%
Sand
25,0%
Silt
41,7%

SoilGrids 250m (ISRIC, 2017) · GLiM v1.0 (Hartmann & Moosdorf 2012)

Land cover

Forest8.2%
Crops38.1%
Built-up3.8%
Bare soil0.6%
Other (grassland, water…)49.4%

Copernicus Global Land Cover 100m (Buchhorn et al. 2020)

Hydrology2 basins · 2 lakes · 9 rivers

Hydrology metrics for this exact territory

Stream length here

31,0km

Lake surface here

0,19km²

Basins crossed

2

Max stream order

2

Max drainage

1 905km²

Discharge in basins

1,7m³/s

Mean precip.

791mm/an

Mean T°

9,2°C

Moisture idx

0,24

Max snow

11%

Mean runoff

489mm/an

Mean elev. (basins)

-2m

Watersheds crossing here

Lakes (2, top by area)

Live spatial overlap (cached after first hit) · HydroBASINS lev08 × HydroLAKES × HydroRIVERS v10

Human pressure

Pop. density

5hab/km²

Night light

5,5nW

Built-up

377,9%

Pesticides

51,8kg/km²

GHSL POP/Built 2020 · VIIRS lumière nocturne · PEST-CHEMGRIDS 2020 (Maggi et al.)

Protected areas7

IUCN Not Reported · 4IUCN IV · 2IUCN Not Assigned · 1🌊 Marine · 1

NNN-NH

IUCN Not Assigned

Nature Reserves owned by professional nature management organizations · 2018

566 km²

Eilandspolder

IUCN Not Reported

Special Protection Area (Birds Directive) · 2000

14 km²

Complete list

WDPA (World Database on Protected Areas) — UNEP-WCMC & IUCN