Introduction

The publication of When Ecology Urbanizes and the recent associated research work (PUCA, BAUM, Métropolitiques) illustrate a major development: urban ecology is becoming a structured scientific field, focused not on greening, but on the mechanisms that regulate life in cities.

Soils, urban forms, ecological continuities, cohabitations, adaptive dynamics: the "living city" is now analyzed as a biological system, subject to measurable interactions.

For IRICE, an independent assessment body, this development is not merely conceptual. It confirms a profound transformation: urban biodiversity can be rigorously measured, and therefore assessed.

1. When research refocuses the city on its living mechanisms

The book highlights a clear break with previous approaches to "nature in the city." Recent research no longer focuses on the presence of vegetation as an end in itself, but on the functional mechanisms that urban systems enable (or prevent):

• ecological functions: movement, reproduction, feeding;
• pressures exerted by morphology: waterproofing, fragmentation, heat, management;
• internal and metropolitan continuities: matrices of displacements, permeabilities;
• multi-species cohabitation: interactions, conflicts, adaptations;
• living soils: earthworms, microfauna, biological qualities.

This analytical framework shifts urban biodiversity into an objective domain, compatible with evaluation.

2. A scientific convergence with independent, evidence-based frameworks

Without proposing an operational tool, the book confirms a strong trend: urban biodiversity must be understood from measurable processes.

This approach aligns with the foundations of IRICE's frameworks:

• taking into account the pressures exerted by urban forms,
• the analysis of actual ecological functionalities,
• the integration of the temporal dynamics of living organisms,
• the qualification of cohabitation in dense urban fabrics,
• evaluating results, rather than intentions.

These elements are at the heart of the methodological structures used in Effinature certification and in independent assessment via the Biodiversity Performance Score (BPS).

The work therefore confirms a theoretical convergence, without this being sought: the research describes the mechanisms; the independent reference frameworks translate them into verifiable criteria.

3. What this changes for local authorities and project owners

The rise of urban ecology as a science implies three major changes in projects:

(1) The focus is shifting from “greening” to ecological performance

The question is no longer: where to plant? But: what ecological mechanisms are actually being supported?

(2) Diagnostics must integrate mechanisms at multiple scales

Plot → block → neighborhood → territory. A localized intervention only has effects if it fits into these continuities.

(3) Independent evaluation becomes structuring

In a context where research provides mechanistic models, the operational challenge becomes: how to guarantee an impartial, stable analysis that is compatible with these mechanisms?

This is where independent, evidence-based frameworks become relevant.

4. IRICE: Translating science into independent assessment

The approach developed over several years by IRICE directly addresses this scientific evolution, without replacing it:

• Effinature applies ecological mechanisms to real estate projects to qualify the performance of living systems.
• The BPS allows projects to be evaluated according to these same mechanisms, without issuing certification, in a logic of independent analysis.

These tools do not comment on the book. They only show that the scientific trajectory described in the book corresponds to a methodological requirement already present in impartial evaluation.

Conclusion

Urban ecology is undergoing a profound transformation: it is becoming a science of urban life, structured by the analysis of ecological mechanisms. The book *When Ecology Urbanizes* offers a clear synthesis of this, confirming that urban biodiversity is no longer merely a matter of discourse, but a quantifiable, comparable, and verifiable field.

In this context, independent assessment tools play an essential role: they allow us to translate this scientific knowledge into measurable benchmarks, capable of supporting the transition from the "built city" to the living city.