MEAN SPECIES ABUNDANCE: HOW TO MEASURE THE BIODIVERSITY IMPACT OF AN INVESTMENT PORTFOLIO?

EXTERNAL ARTICLE

Estimated reading time: 4 min.

As biodiversity loss becomes a systemic risk, finance must find ways to measure its footprint on nature. But how do we translate supply chains, emissions, and land use into a meaningful biodiversity impact? The answer lies in the MSA metric, and in combining scientific models like GLOBIO with economic datasets like EXIOBASE.

MSA stands for Mean Species Abundance. It reflects how intact an ecosystem is, from 1 (pristine) to 0 (fully degraded). By associating each business activity with land use, pollution, fragmentation, and other pressures, we can estimate the MSA·km² lost per million euros of revenue or investment.

THE LOGIC CHAIN BEHIND BIODIVERSITY IMPACT

1.    EXIOBASE gives resource use and emissions per euro of output for each (sector × country) pair.
2.    GLOBIO translates these physical flows into biodiversity loss (via pressure–impact relationships).
3.    Multiplying the two yields: MSA·km² per M€ — a footprint intensity.
4.    These values are aggregated across the portfolio, weighted by exposure or ownership.
For example, a portfolio exposed to European agriculture may generate 800 MSA·m²/k€, i.e. 0.8 m² of nature degraded for every €1,000 financed.

STATIC VS DYNAMIC

•    Static impact = legacy land occupation or fragmentation still present today (e.g. cropland, pasture).
•    Dynamic impact = additional degradation caused during the current year (e.g. deforestation, emissions, fertilizer use).
•    Both are essential to understand long-term risks and short-term performance.

WHAT DATA IS NEEDED?

•    Minimal: revenue breakdown by sector and geography.
•    Better: internal Scope 1–3 inventories.
•    Advanced: LCA data or detailed supplier-level emissions and land use.

WHY IT MATTERS FOR ASSET MANAGERS

MSA-based indicators enable:
•    portfolio footprinting (MSA·m²/k€, or MSAppb),
•    engagement with companies and sectors,
•    exclusion or prioritiZation policies,
•    alignment with TNFD, CSRD, or “nature-positive” targets.

By linking scientific insight to economic flows, biodiversity impact becomes measurable, and actionable, in financial terms. A critical step toward aligning portfolios with global nature goals by 2030.

USEFUL SOURCES
 

• Schipper, A. M., et al. (2020). Projecting terrestrial biodiversity intactness with GLOBIO 4
• Hudson, L. N., et al. (2016). The PREDICTS database: A global database of how local terrestrial biodiversity responds to human impacts. Ecology and Evolution, 6(21), 7014–7035
• Stadler, K., et al. (2018). EXIOBASE 3: Developing a time series of detailed environmentally extended multi-regional input–output tables
• CDC Biodiversité (2022). Global Biodiversity Score: Technical documentation – Version 2022
• FAIRR Initiative (2024). Corporate Biodiversity Footprints: Data and Case Studies Supporting Investor Action on Biodiversity