Abstract
The aim of the Norwegian Nature Index (NI) is to provide an overview of the state of biodiversity within and across major ecosystems. The index is composed of a series of indicators, each representing individual species or diversity measures. The indicators are standardized and scaled in relation to a reference state, and combined for ecosystems or geographical regions, to give a number between 1 (reference state) and 0 (seriously degraded biodiversity). In 2010, the state of biodiversity was highest in mountains, ocean, coastal waters, and freshwater (NI=0.69–0.80), intermediate for mires and wetlands (NI=0.55), and lowest for open lowlands and forests (NI=0.43–0.44). The NI increased 8–10% in freshwater and the ocean (bottom and pelagic) from 1990–2010, but decreased by>10% in open lowlands during the same period. Since its launch in September 2010, the Nature Index has been approved by the Ministry of Finance as an indicator for biodiversity in the set of sustainable development indicators and approved by the Ministry of Environment as an indicator of the state of major ecosystems.