Environmental Value Assessment Scenario Tool (EVAST)
EVAST simulates the potential effects of government policies - specifically Defra's Environmental Land Management (ELM) scheme - on ecosystem service stocks, flows and values. It allows the ELM scheme to be developed, explored and stress-tested before implementation, including potential impacts on Defra's key priority areas of Biodiversity, Net Zero, Water Quality and Air Quality.
The EVAST modelling framework was co-designed with Defra by a UKCEH-led consortium to support the development of the Environmental Land Management (ELM) scheme. It comprises linked component models which respond to changes in land use and management at the most appropriate spatial resolution (down to field scale) to provide information on changes in ecosystem service stocks and flows including their associated monetary and non-monetary value. Component models are soft-coupled by passing data-cubes between partner organisations; these models include process-based, statistical and GIS models. The framework models changes related to Defra's key priority areas of Biodiversity, Net Zero, Water Quality and Air Quality.
Development of the EVAST modelling framework began in December 2019 and the project is due to complete in December 2023.
EVAST is co-created and custom-designed with Defra using an interative and responsive approach to make it particulary policy-relevant and impactful: (1) it fits Defra's wider modelling strategy; (2) it is informed by latest thinking on Defra's ELM scheme design; (3) it builds understanding between Defra personel and EVAST consortium modellers to improve understanding and confidence in the strengths and limits of modelling; (4) the cross-sectoral, integrated modelling approach works across Defra priority areas at the highest appropriate resolutions to identify synergies and trade offs between policy approaches and environmental sectors. These factors combine to support more nuanced decisions that reflect interactions between policy aims across environmental priorities (e.g. Carbon, Water quality, Biodiversity).
Development of EVAST is led by UKCEH in collaboration with Defra and a consortium including: ADAS; British Trust for Ornithology; Cranfield University; eftec (economics for the environment consultants); Forest Research.
Access to EVAST is restricted to lincenced users: Defra.
Development of EVAST is funded by Defra.
EVAST is used by Defra who commissioned it for policy planning.