Biodiversity and ecosystem services net gain assessment: A comparison of metrics

Biodiversity offsetting aims to mitigate the impacts of development through habitat restoration or creation. Biodiversity net gain seeks to go further by achieving an increase in biodiversity. There is further interest in the wider ecosystem services impacts of development, although this broader scope may increase the resources required for assessments. We apply a habitat map based approach to biodiversity and ecosystem services net gain on a site in central Scotland where there is a proposal combining development, land use change and habitat creation. The results suggest that biodiversity net gain can be achieved through trading-up to more distinctive habitats and improving habitat condition. The loss of ecosystem services was not offset, whether considering the potential for the affected habitats to supply services, or the demand for services as indicated by their value. However, the valuation did not account for changes in the numbers of service beneficiaries, although these will increase the value of services the pressure on supply is also increased. The broadening of the application of ecosystem services assessments into planning and development also creates trade-offs between the sophistication of assessment approaches and their usability by non-specialist practitioners.