An Australian-based biodiversity intelligence startup has developed a model incorporating global and local metrics to assess ecosystem and species health, seeking to enhance data comparability and steer companies in nature-related disclosures.
Xylo Systems reviewed existing biodiversity metrics, including those suggested by the Taskforce on Nature-related Financial Disclosures (TNFD), and selected the most suitable ones to inform its Biodiversity Model.
“While a single, comprehensive metric is appealing for its simplicity and comprehensibility, it can be misleading without proper contextual understanding,” the company said in a white paper released on Wednesday.
The analysis took into account nine global biodiversity metrics focused on ecosystem conditions:
- Red List of Ecosystems (RLE)
- Red List Index of Ecosystem (RLIE)
- Ecosystem Health Index (EHI)
- Ecosystem Intactness Index (EII)
- Ecosystem Area Index (EAI)
- Proportion of Land Degraded (PLD)
- Marine Cumulative Human Impacts (MCHI)
- Forest Landscape Integrity Index (FLII)
- Ecosystem Integrity Index (Ell)
The latter was selected as the most effective metric, as others apply only to specific ecosystems, such as MCHI and FLII, do not include spatial data, like RLIE, EHI, and EAI, or – as in the case of PLD – require additional data input, according to Xylo Systems.
The paper also considered three separate metrics on species extinction risk – Species Threat Abatement and Restoration (STAR), Biodiversity Intactness Index (BII), and Mean Species Abundance (MSA), the former being the only one that has been performance tested.
“However, as its coverage of taxa is currently still fairly limited and it has a fairly coarse resolution, we have found that it needs to be supported by a second metric,” said the paper.
“Compared to MSA, which focuses more on species abundance, the BII incorporates both abundance and compositional similarity to a predicted baseline of no human disturbance, and is therefore a more robust option.”
ENABLING COMPARISONS
Researchers then looked at local biodiversity metrics, which have the potential to capture on-site species richness and evenness but, unlike global ones, typically do not allow for comparisons between different locations across the world.
Xylo Systems picked the Global Biodiversity Information Facility (GBIF), which aggregates primarily crowd-sourced data, giving a comprehensive overview of the species present in an area, though data collected from citizen science often contains biases from the lack of standardisation, according to the paper.
“We addressed data limitations from crowd-sourced GBIF using rarefaction and standardisation by coverage, and designed a species richness measure that is easily interpretable and comparable between projects when referenced against the BII,” it said.
“As the BII is a measure of abundance and compositional similarity, it can be used to indicate if the local biodiversity observed is low or high compared to the habitat’s baseline.”
In recent months, pressure has mounted on companies and financial institutions to assess their impacts on nature, along with the emergence of voluntary and mandatory reporting schemes, such as the TNFD recommendations and the EU’s Corporate Sustainability Reporting Directive (CSRD).
Last week, French-headquartered bank BNP Paribas said combining a set of metrics largely focused on species abundance and diversity, including MSA and BII, can help companies effectively bridge biodiversity monitoring gaps.
By Sergio Colombo – sergio@carbon-pulse.com
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