Ecometrica’s Normative Biodiversity Metric: is it really a good idea?

Ecometrica, a Scottish consultancy, just wrote up guidelines for a new biodiversity metric. The Normative Biodiversity Metric (NBM) uses an interesting shortcut between “pristine” land and biodiversity to assess the overall land-holdings of the organization being assessed.

Because the metric uses widely applicable classes of “pristiness”, it can itself be widely applied, at various spatial scales. In fact, NBM relies on existing mapped data concerning land-use and land-cover. This wide applicability is the metric’s main strength.

In trying to apply concepts and ideas developed for green house gas emissions (GHG) to biodiversity, Ecometrica has chosen to simplify the later to a single easy to use metric. Why not? That choice does however raise the issue of over-simplification. When does “pristine” actually equate biodiversity and is that particular biodiversity the most relevant one to consider in assessing an corporation’s impact?

The NBM is designed to provide an equivalent to corporate GHG assessment, for biodiversity impact.

The documentation shows that the metric can incorporate additional field information, e.g. from surveys of the species or habitats that are actually present on-site. Yet, it is clear that the metric was developed to avoid field surveys as much as possible:

the biodiversity assessment methodology cannot be wholly dependent on the use of ecological surveys carried out by experts

Is that really a good idea? As usual, it depends what you use the metric for…

2 Responses to “Ecometrica’s Normative Biodiversity Metric: is it really a good idea?”

  1. Martin says:

    Is it a good idea? Well, how about “is it a workable idea”? There are many problems with the paper and the concepts it outlines, but the principal one is the scale against which they intend to measure the “value” of biodiversity. This scale runs from “artificial” land cover to “pristine” areas. The paper gives examples of both – artifical cover includes built environments, while prisine areas are exemplified by rain forest and coastal wetlands.

    If the index is to be useful, there has to be an operational definition to allow people independently to decide how to locate the condition of a landscape or ecosystem on this scale. Until we can agree on what we mean by “pristine”, or any of the other gradations in their scale, this NBM is an arbitrary, subjective and unworkable index.

  2. I want to highlight here one of the key questions the same people from econometrica raise for their work:
    “Subjectivity in assigning pristineness classes – How can this be addressed?”
    there is a lot in to this and the index is not useful.

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