What are biodiversity units
Biodiversity units in the UK are used as part of the biodiversity metric, an official and statutory term referring to a way of measuring biodiversity value for the purposes of the Biodiversity Net Gain (BNG) regulations. For this purpose there are three types of biodiversity units, which are calculated in three separate modules or types used; area units, hedgerow units and watercourse units.
The metric approach is used to calculate how many units a habitat contains before a development takes place and how many units are needed to replace the units of habitat lost in order to achieve 10% BNG according to the regulation, through the creation or enhancement of habitat.
The biodiversity metric used to calculate biodiversity units takes into consideration the size, condition, strategic significance and type of the habitat under consideration. For habitats that are enhanced or newly created, the formula also takes account of; the difficulty of the creation or enhancement, the time it takes a habitat to reach its target condition and the distance from the habitat loss.
It measures all types of habitat, including:
- grassland
- hedgerows
- lakes
- woodland
- watercourses such as rivers and streams
The statutory (official) biodiversity metric calculation tool must be used in order to demonstrate that a developer has calculated the number of biodiversity units for existing habitat or habitat enhancements in accordance with the statutory biodiversity metric.
For further information on the Biodiversity Net Gain (BNG) visit here
For further information on the biodiversity metric calculation tools and guides visit here
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