Scientists Propose a Single ‘Biodiversity Equivalent’ Metric to Rival CO2 Accounting

A team of Finnish researchers has unveiled a new accounting framework that could do for biodiversity what the carbon dioxide equivalent did for climate: compress the dizzying complexity of global species loss into a single, comparable number that can sit directly on a company’s income statement. The method, called the Biodiversity Equivalent Impact Assessment, or BIOVALENT, was developed by scientists at the University of Jyväskylä and published in the Journal of Industrial Ecology. Its central innovation is the biodiversity equivalent, a spatially explicit measure of the potential global loss of species across terrestrial, freshwater and marine ecosystems, expressed as the fraction of the world’s species at risk of extinction due to an organization’s activities.

The motivation is stark. Biodiversity loss is driven by land and sea use change, direct exploitation of nature, climate change, pollution and invasive alien species, all of which stem from deeper root causes such as consumption patterns, trade and governance. Organizations sit at the heart of that system: direct emissions from roughly 9,000 companies accounted for more than 38 percent of global greenhouse gas emissions in 2021, and the environmental impacts of nearly any organization ripple through international supply chains to every corner of the planet. Yet while carbon footprinting has matured into a routine corporate practice, biodiversity footprinting remains fragmented, with a patchwork of methods that are difficult to compare across regions and value chains.

The core problem the researchers set out to solve is one of perspective. Existing biodiversity indicators are typically regional, meaning they weigh a hectare of degraded land in Finland the same as a hectare in Brazil. The team illustrates the trap with a simple example. Suppose an organization converts 200 hectares in Finland where 25 percent of species abundance remains, and 100 hectares in Brazil where 50 percent remains. A regional metric based on Mean Species Abundance would score both impacts identically at 50 MSA-hectares. But when the same impacts are evaluated with a global metric, the Potentially Disappeared Fraction of Species from the LC-IMPACT database, the Brazilian footprint comes out roughly 42 times larger than the Finnish one, because Brazil hosts far more species found nowhere else on Earth.

That difference matters for decision-making. Regional indicators ignore the global distribution and vulnerability of species, so two organizations with identical regional footprints may have radically different true impacts on global species richness. For a multinational with supply chains spanning dozens of countries, regional metrics make it nearly impossible to prioritize where action would deliver the greatest benefit for global biodiversity. The researchers argue that because trade flows distribute biodiversity impacts worldwide, organizations need indicators that can identify, report and compare impacts across global value chains in a unified way.

The biodiversity equivalent builds on the global Potentially Disappeared Fraction of Species indicator by weighting ecosystem-specific footprints with the estimated number of plant and animal species in each realm. The formula multiplies the terrestrial footprint by 0.801, the freshwater footprint by 0.096 and the marine footprint by 0.102, reflecting the estimated share of the world’s species living in each ecosystem type. The result is a single number that estimates what fraction of the planet’s species are at risk of global extinction from a given activity. Because the values are tiny, they are reported with metric prefixes such as nano, pico or femto biodiversity equivalents, mirroring the way kilograms of carbon dioxide equivalents become tonnes. Crucially, the metric captures the intuition that the same pressure causes less global harm in species-poor regions than in species-rich ones, while equal biodiversity equivalent values mean equal fractions of global species potentially lost, wherever they occur.

Turning the metric into a practical tool required a six-step methodology. First, an organization selects the activities to assess, with system boundaries essentially set by its financial accounts. Second, it quantifies the drivers of biodiversity loss, such as land use or greenhouse gas emissions, caused per unit of each activity, drawing on life cycle assessment and environmentally extended input-output analysis. Third, the location of each driver is traced using regionalized databases like ecoinvent and EXIOBASE, and spatially explicit biodiversity impact factors are calculated by combining the location matrix with LC-IMPACT data. Fourth, the organization’s activity data are harmonized with the LCA and input-output classifications. Fifth, ecosystem-specific footprints are calculated and merged into the biodiversity equivalent. The resulting global impact factors have been released as an open database so that other organizations, experts and researchers can apply the method without rebuilding it from scratch.

The sixth step is the most provocative: assembling a value-transforming financial-environmental impact statement. The researchers argue that environmental accounting today remains superficially integrated with financial reporting and is routinely ignored in management decisions, even though organizational decision-making is ultimately guided by financial accounts. Their solution is to give footprints a monetary cost that becomes visible in the income statement, for instance by financing offsets that match the calculated carbon and biodiversity footprints. Once footprints carry a price, they alter the financial value of the organization itself, forcing senior executives and investors to confront environmental damage in the same ledger where profits and losses live.

To test the framework, the team used the University of Jyväskylä as a living lab. The institution, with 14,600 degree students, 2,800 staff members and an annual turnover of 230 million euros, is comparable in scale to a large corporation. The results were revealing. The university’s carbon footprint fell 15 percent between 2019 and 2023, from 22,723 to 19,405 tonnes of carbon dioxide equivalents, as heat and electricity emissions declined. Yet its biodiversity footprint stayed essentially flat at 58 nano biodiversity equivalents, because a shift to biomass in energy production and rising purchases of items like IT equipment and food offset the gains. The finding underscores how carbon reductions alone can mask persistent biodiversity harm, and how a unified metric exposes trade-offs that separate reporting would hide.

The offsetting demonstration produced the study’s most striking numbers. Using the World Bank’s carbon price for the European Union, about 96 US dollars per tonne of carbon dioxide equivalent in 2023, and a purpose-built biodiversity offsetting cost, the researchers calculated what it would cost the university to offset its 2023 footprint. If the cost were spread over 30 years like the depreciation of a large investment, offsetting in Finland would cost roughly 435.78 million euros annually, while the same global biodiversity offset completed in Brazil would cost around 0.60 million euros. The biodiversity equivalent, being location-independent in the way the carbon dioxide equivalent measures global warming potential, allows impacts distributed across the world to be offset anywhere, and the team is candid that this global offsetting idea is controversial and deliberately simplified for illustration.

The authors acknowledge the risks. Monetizing nature could legitimize further destruction, and carbon offsetting schemes have repeatedly failed to achieve additionality, a problem that plagues biodiversity offsetting as well. Offsetting in species-rich countries more cheaply than in species-poor ones raises uncomfortable questions about equity between the Global South and Global North, even as the researchers argue the method could help expose and mitigate the unsustainable appropriation of resources from the South. The biodiversity equivalent also cannot capture genetic, functional and ecosystem diversity, and it merges drivers that behave differently over time, since land use impacts do not accumulate the way greenhouse gas concentrations do. Still, the team believes the metric could let organizations benchmark themselves against global goals such as the Kunming-Montreal target of reducing extinction rates tenfold by 2050, and that value-transforming accounting, backed by regulation, taxation and mandatory offsetting, is essential to drive the transformative changes in production and consumption needed to halt biodiversity loss.

Subject of Research: Integrated carbon and biodiversity footprint accounting with a unified biodiversity equivalent metric

Article Title: Value-transforming financial, carbon and biodiversity footprint accounting

Article References: El Geneidy, S., Peura, M., Aumanen, V.-M., Baumeister, S., Helimo, U., Vainio, V., & Kotiaho, J. S. (2026). Value-transforming financial, carbon and biodiversity footprint accounting. Journal of Industrial Ecology. https://doi.org/10.1007/s44498-026-00151-8

Image Credits: AI Generated

DOI: 10.1007/s44498-026-00151-8

Keywords: biodiversity footprint, biodiversity equivalent, carbon footprint, financial accounting, environmental accounting, life cycle assessment, EXIOBASE, LC-IMPACT, biodiversity offsetting, species extinction, corporate sustainability, industrial ecology