Scotland's Natural Capital Asset Index

Natural capital is a term for the habitats and ecosystems that provide social, environmental and economic benefits to humans. Scotland has a wide range of these habitats and ecosystems—each of which makes a unique contribution to the people’s wellbeing. Natural capital helps make the invisible benefits and value of nature visible. And the Natural Capital Asset Index is one tool to include nature in policy decisions where it historically has been overlooked, undervalued and unaccounted for.

The Natural Capital Asset Index (NCAI) is a composite index which tracks changes in the capacity of Scotland's terrestrial ecosystems to provide benefits to people. It does not include the benefits from the marine environment (although a feasibility study assessing whether this is possible was carried out in 2019).

Historically, Scotland's natural capital deteriorated until the 1990s. Most habitats were declining during this period, especially bogs and grassland. Evidence from the NCAI suggests the potential of Scotland’s habitats to deliver ecosystem services has improved over the past 20 years and has now plateaued around its peak in 2017, as seen in Figure 1. Further details can be found in the Natural Capital Asset Index 2023 summary.

The Natural Capital Asset Index is included as a measure for the National Indicator 'Increase our natural capital' in the National Performance Framework. Recently released data for the year 2021 suggests that Scotland’s stock of Natural Capital is being maintained. The capacity of ecosystems to provide benefits fluctuates over time due to changes in habitat quantity and quality. We track habitat quantity in the NCAI using what we know about land cover change in Scotland. Habitat quality is tracked using 38 separate indicators which rely on datasets gathered by a range of public organisations and citizen science schemes.

The full Natural Capital Asset Index 2023 used to track the change in Scotland’s natural capital is available online while the full history of the development of the NCAI and the theoretical underpinnings that support it can be found in our journal article, published by Ecological Indicators.