Related Experiment Video
Updated: Sep 11, 2025

Measuring the Structure, Composition, and Change of Underwater Environments with Large-area Imaging
Published on: April 18, 2025
Assessing biodiversity trends in a quasi-permanent non-equilibrium state
Etienne Lalechère1, Jonathan Lenoir2, Ronan Marrec2
1Center for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway; Centre for Computational and Data Science, University of Oslo, Oslo, Norway.
Biodiversity assessments often assume equilibrium, but long-term disturbances create non-equilibrium states. This study proposes a new framework using temporal influence functions to model these dynamic biodiversity trends.
Area of Science:
- Ecology
- Environmental Science
- Biodiversity Research
Background:
- Traditional biodiversity trend assessments rely on the 'equilibrium assumption,' assuming biodiversity is always balanced with current environmental drivers.
- Existing non-equilibrium frameworks still maintain that biodiversity is in equilibrium with contemporary drivers at any given time.
Purpose of the Study:
- To challenge the prevailing equilibrium assumption in biodiversity trend assessments.
- To propose a new conceptual framework for understanding and modeling biodiversity under long-term, non-equilibrium conditions.
- To introduce temporal influence functions for ecological modeling.
Main Methods:
- Conceptual analysis of biodiversity dynamics under long-term disturbances.
- Development of a novel framework based on temporal influence functions.
- Integration of the framework into existing ecological models.
Main Results:
- Identified that long-term disturbances can lead to quasi-permanent non-equilibrium biodiversity states.
- Proposed a flexible conceptual framework applicable to diverse ecological models.
- Demonstrated the potential of the framework for hindcasting past and projecting future non-equilibrium biodiversity trends.
Conclusions:
- The equilibrium assumption is a significant limitation in understanding biodiversity responses to environmental change.
- A paradigm shift towards non-equilibrium dynamics is necessary for accurate biodiversity assessments.
- The proposed temporal influence function framework offers a powerful tool for ecological research and conservation.
Related Concept Videos
Conservation of Declining Populations
Habitat Fragmentation
What is Biodiversity?
Conservation of Small Populations
Threats to Biodiversity
Ecological Disturbance

