Biodiversity Intactness - Biodiversity Intactness Index
Overview
Data Type | Ecological modelling and remote sensing data on pressures |
|---|---|
Source | |
Spatial Resolution | 100m |
Temporal Resolution | The BII data is available for the years 2017-2020. Updates are expected regularly. |
Interpretation | The BII estimates how intact an area's biodiversity is compared to a reference area unaffected by human pressures. For example, a BII score of 5.3 indicates that at this location only 53% of the biodiversity present in an undisturbed reference area remains. |
Concern Level | Very Low = Score 0 - 2 Low = Score 2 - 4 Moderate = Score 4 - 6 High = Score 6 - 8 Very High = Score 8 - 10 |
Framework Relevance | BII is relevant under CSRD (ESRS E4) as well as under TNFD and SBTN. |
Detailed Specification
Explanation
The Biodiversity Intactness Index (BII) is a global index estimating the change in biodiversity intactness in response to human pressures. Biodiversity Intactness is estimated as a combination of two metrics: Abundance, the quantity of individuals of a species, and Compositional Similarity, how similar the composition of species is to an intact baseline. The index is the output of a global spatial model. The model is calibrated based on the PREDICTS database which includes spatially referenced species observations from over 750 studies and 32’000 sites. The modelled human pressures are based on remote sensing data for crop land, built areas, roads, proximity to cities, population density, forest area and tree cover loss.
Transformation & Interpretation
The BII metric is the multiple of estimated values for Abundance and Compositional Similarity. The values have been normalized to a 0-100 scale by dividing the modeled value for an area without any human influence. The raw BII values are scaled to a range from 0 to 10 by dividing by the factor 10.
BII Values (%) | Score | Concern Level |
|---|---|---|
≤ 20% | 0 - 2 | Very Low |
20% - 40% | 2 - 4 | Low |
40% - 60% | 4 - 6 | Moderate |
60% - 80% | 6 - 8 | High |
> 80% | 8 - 10 | Very High |
The BII reflects the level of biodiversity intactness, where a score of 0 indicates complete biodiversity loss and a score of 10 represents fully intact, undisturbed biodiversity. For instance, a BII score of 5.3 means that only 53% of the biodiversity found in an undisturbed reference area remains at this location.
Note that the methodology used to convert BII to Concern Level was updated in January 2025. For completeness, the previous methodology is included at the bottom of the page
Source
The BII indicator is sourced from the Microsoft Planetary Computer and developed by Gassert et al. (2022).
Date of publication
2023
Confidence & Accuracy
Medium (best available at global scale). The BII provides large scale consistent monitoring of biodiversity intactness based on remote sensing data on human pressures and following a transparent methodology. Making it a useful for global comparison and prioritization. However, caution should be taken in interpreting the data at the local scale and the data is best complemented with additional indicators for biodiversity intactness.
Relevance for CSRD
CSRD requires companies to assess the condition of biodiversity and ecosystems around their sites. For this, the Biodiversity Intactness index is relevant under:
ESRS Article | Disclosure or application requirement |
|---|---|
ESRS E4 DR 16 (a) (ii) | breakdown of sites according to ecological status of the areas (with reference to the specific ecosystem baseline level) |
ESRS E4 DR 41(b) | disclose with regard to ecosystems condition |
ESRS E4 DR 41(b) (i) | metrics for quality of ecosystems relative to a pre-determined reference state |
ESRS E4 DR 41(b) (ii) | metrics for multiple species within an ecosystem (...) species richness and abundance indicators (...) against the reference state |
ESRS E4 DR 41(b) (iii) | metrics that reflect structural components of condition |
ESRS E4 AR 7 (c) | identify current integrity and importance of biodiversity and ecosystem at each location |
CSRD requires companies to consider and describe the data used in their analysis (ESRS E4 AR 27). For convenience, here a description of the relevant criteria:
ESRS Data Criteria | Comment |
|---|---|
(a) methodology, | Methodology: BII is estimated based on a global ecological model combining species observations and remote sensing data. Reason for selection: The indicator has been selected to assess the condition of ecosystems and biodiversity. The selected metric is science-based, peer-reviewed, widely used. Assumptions: The indicator is model based and incorporates several assumptions detailed in Gassert et al. (2022). Limitations & uncertainties:The BII provides large scale consistent monitoring of biodiversity intactness based on remote sensing data on human pressures and following a transparent methodology. Making it a useful for global comparison and prioritization. However, caution should be taken in interpreting the data at the local scale and the data is best complemented with additional indicators for biodiversity intactness. |
(b) scope of metric | The BII indicator is applied at site level. |
(c) biodiversity component of metric | The BII is mainly an ecosystem-level nature indicator. It estimates ecosystem composition by providing variables on species abundance and compositional similarity. Through the use of species-level output variable BII also can be considered contributing to the estimation of species-level biodiversity components of population size and extinction risk. |
(d) covered geographies | The BII indicator has global coverage. |
(e) integration of ecological thresholds | The BII indicator does not relate to a specific planetary boundary although the model integrates several human pressures that relate to planetary boundaries, land-system change in particular. |
(f) frequency of monitoring, baseline condition and period | The BII indicator is expected to be updated annually. |
(g) data type (primary, secondary, modelled, expert judgement | The BII indicator relies on modelled data. |
Relevance for TNFD
The BII indicator is a suitable indicator to estimate ecosystem composition under the criteria of Ecosystem Integrity within TNFD’s LOCATE step.
Relevance for SBTN
The BII indicator is a suitable biodiversity State of Nature indicator useful to SBTN Step 1: Assess and Step 2: Interpret & Prioritize.
| SBTN Data & Tool Criteria | Evaluation | Comment |
|---|---|---|
Relevance | ✅ | BII is a biodiversity state of nature indicator aligned with SBTN methodology. |
Representative | ✅ | BII data represents a close fit with the SBTN characterization of biodiversity state of nature indicators and is appropriate to be applied under Step1: Assess and Step 2: Interpret & Prioritize. |
Spatial and Temporal Resolution | ✅ | The BII indicator is provided at the spatial resolution a 100-meter grid. The BII data is available for the years 2017-2020. |
Stability and Preservation | ✅ | BII data sets are likely to be maintained and preserved long-term as they are provided by established remote sensing companies and available through Microsoft Planetary Computer and Google Earth Engine. |
Accessibility | ✅ | The BII data is readily accessible online. |
Interpretability | ✅ | The BII indicator is sufficiently interpretable and generates an appropriate input for the SBTN methodology. |
Coverage | ✅ | BII has global coverage. |
Authoritative and Accurate | ✅ | BII data is based on the well established PREDICTS data base and a transparent and science-based methodology. |
Previous methodology [pre-January 2025]
Transformation & Interpretation
The BII metric is the multiple of estimated values for Abundance and Compositional Similarity. The values have been normalized to a 0-1 scale by dividing the modeled value for an area without any human influence. The global distribution of BII values is heavily negatively skewed. This means that most global values lie within the range of 0.8 and 1 with relatively few values below. The uneven distribution of BII values complicates a meaningful interpretation of the normalized value itself. In order to ensure an intuitive and ecologically meaningful interpretation the following transformation is applied.
- The raw BII values are converted into their global percentiles (their relative position within the global distribution of BII values, expressed as a percentage).
- The percentile values are divided by 10 in order to align with the 0-10-scale of most Nala State of Nature indicators.
The interpretation of the BII score resulting from this transformation is straightforward and ecologically meaningful. A site having an BII score of 6 means that 6 out 10 global areas have a lower modelled biodiversity intactness (abundance & compositional similarity) than the area of interest.
The scores are translated into Concern Levels applying the following intervals:
Very Low = Score 0 - 2
Low = Score 2 - 4
Moderate = Score 4 - 6
High = Score 6 - 8
Very High = Score 8 - 10