BiodiversityView Technical Details
BiodiversityView – Methodology Overview
The Map Impact methodology combines several data sources, alongside a novel satellite imagery analytics approach, to infer biodiversity condition, at any location.
Habitat Datasets
Map Impact’s solution currently utilises ancillary open-source datasets to identify habitat types. Habitat types align with the UK Habitat Classification (UKHAB) system, although currently available open-source data does not allow all habitats to be represented. Map Impact are a UKHAB Partner, and the UK Habitat Classification is used under license, with no onward licenses implied or provided. All rights reserved.
Each habitat is provided with a distinctiveness score, which assigns additional weighting to the final biodiversity score. The distinctiveness of each habitat is defined within the DEFRA Biodiversity Metric Calculator 4.0.
Ancillary habitat data sets are layered in a defined structure to provide the best available view of habitats. The following data sources and licenses are used:
- Living England: Satellite-based habitat classification, published by Natural England. Subject to the Open Government License.
- Priority Habitat, published by Natural England. Subject to the Open Government License, and Creative Commons License.
- Wood Pasture and Parkland, published by Natural England. Subject to the Open Government License.
- Open Mosaic, published by Natural England. Subject to the Open Government License.
- Greenspace, published by Ordnance Survey. Subject to the Open Government License.
- OpenStreetMap, licensed under the Open Data Commons Open Database License.
Satellite Imagery
Map Impact is utilising the Sentinel-2 satellite constellation operated by the European Space Agency. This is due to the historical archive of available satellite images (back to 2015), high frequency of collections, and the number of spectral bands which provide a range of indices that can be used to infer the condition of each habitat.
Satellite imagery is processed and analysed using Google Earth Engine. The use of Sentinel data is governed by the Copernicus Sentinel Data Terms and Conditions.
Hexagon grid
Map Impact is utilising the H3 Hexagonal hierarchical geospatial indexing system as a foundational layer with which to define a biodiversity score that combines both the habitat type and condition of habitat. The outcomes will be displayed using this hexagonal grid, utilising Resolution 11, where the length of each edge of the hexagon are approximately 29 metres, the longest distance across the hexagon is approximately 50 metres, and the area of each hexagon is approximately 0.2 hectares. The hexabin grid is chosen since it allows for a higher degree of connectivity to best reflect the true nature of habitats, with more adjacent cells than a square grid can provide.
Condition Score Range
This can be considered both an input and a variable. The current score range is 1 to 3 to align with the DEFRA Biodiversity Metric Calculator, where condition scores are deemed “Good, Moderate, or Poor.”