Places / horaholm-oncra-hor-l-001-hornhuizen

Horaholm (Oncra HOR-L-001), Hornhuizen

55.05 ha · arable, regenerative · NL · centroid 53.4014, 6.3664

Oncra registry project HOR-L-001: 55 ha regenerative arable and vegetable farm, biodynamic since 2020, Hornhuizen (Groningen). Boundary from the public registry KML (Dijksterweg 12 polder). Registered by the operator as a worked example for carbon inference; the remover is not yet a steward here.

Verdict · 2026-Q4

Insufficient data

unknown: diversity, structure, renewal, cycling, resilience, autonomy

Streams

Satellite: 892 clear observations, 2019-01-21 to 2026-09-26
Sound recorders: 0
Soil probes: 0
Visits: 0

Soil (SoilGrids 250 m, ISRIC, CC BY 4.0): Fluvisols, clay 28.8% · sand 28.4% · silt 42.7% · organic carbon 6.96% · pH 7.2

Last job: satellite.update · done

JSON NDVI CSV Readings JSON Add a device

Seven readings

The verdict is the weakest of the seven. Unknown is a real answer: it says which stream still has to arrive.

Productivityrising

capturing energy and building biomass (satellite greenness over the growing season)

confidence 100% · held 1 period

single-place reading: the last growing season against the place's own previous three; regional weather (a dry spring, a wet summer) is not yet subtracted because the neighbour crowd is not built

Diversityunknown

differentiating into many forms (species heard per year)

confidence 0% · held 0 periods

no sound stream yet: install a recorder and deliver detections

Structureunknown

trophic levels and habitat complexity (acoustic indices)

confidence 0% · held 0 periods

no acoustic indices yet (NDSI/ADI); deliver indices or let the server compute them from detections

Renewalunknown

reproducing and recruiting (breeding-season song)

confidence 0% · held 0 periods

no sound stream yet: breeding-season song is the renewal signal

Cyclingunknown

closing water and nutrient loops (soil breathing from lab samples or a flux probe, corrected for moisture and temperature)

confidence 0% · held 0 periods

no soil stream yet: install a moisture and temperature probe and take a yearly lab sample

Resilienceunknown

recovering after shocks (drought years in the satellite archive)

confidence 20% · held 0 periods

fewer than two shocks (>15% below the place's median) in the archive; resilience cannot be read yet

Autonomyunknown

holding its state with little management (machine noise)

confidence 0% · held 0 periods

no machine-noise signal yet; anthrophony from indices or engine detections from the recorder

Satellite greenness (NDVI), Sentinel-2

Each dot is one clear scene, cloud-masked with the scene classification layer, averaged over the pixels inside the boundary. Shaded bands are growing seasons.

Growing season	Mean NDVI	Clear scenes
2019	0.499	92
2020	0.448	114
2021	0.460	97
2022	0.438	42
2023	0.528	50
2024	0.529	40
2025	0.458	62
2026	0.563	82

Carbon, inferred (v0.1, a range, not an issuance)

Net ecosystem carbon balance per year: productivity from satellite greenness, minus soil breathing (from a temperature climatology until a probe exists), minus harvest export for this land use. Every parameter carries a low and a high value; the range is what the evidence supports. Credits would be issued for the lower bound. Method · JSON

Year	Scenes	NPP t C/ha	Soil breathing t C/ha	Export t C/ha	Net t CO₂/ha (box)	Central
2019	141	5.1 to 9.3	2.6 to 4.7	1.8 to 5.1	-17.4 to 18.0	1.0
2020	173	4.4 to 8.1	2.6 to 4.7	1.5 to 4.5	-17.3 to 14.5	-0.9
2021	154	4.7 to 8.7	2.6 to 4.7	1.7 to 4.8	-17.4 to 16.1	-0.0
2022	78	5.1 to 9.3	2.6 to 4.7	1.8 to 5.1	-17.4 to 18.0	0.9
2023	70	5.8 to 10.7	2.6 to 4.7	2.0 to 5.9	-17.4 to 22.1	3.0
2024	62	5.7 to 10.4	2.6 to 4.7	2.0 to 5.7	-17.4 to 21.3	2.7
2025	102	5.6 to 10.3	2.6 to 4.7	2.0 to 5.6	-17.4 to 20.9	2.4