Ecosystem Resilience
Ecosystem Resilience is the capacity of an ecological system to absorb disturbance, reorganize, and retain essentially the same function, structure, identity, and feedbacks. It is a measure of the magnitude of disturbance that can be absorbed before the system changes its controlling variables and state.
Core Principles
- Resistance vs. Resilience: Resistance is the ability to remain unchanged during disturbance; resilience is the ability to recover after change.
- Adaptive Capacity: The scope for an ecosystem to adjust to climate change, taking advantage of opportunities, or responding to or coping with adverse effects.
- Biodiversity as Insurance: High species richness often correlates with functional redundancy, ensuring that if one species fails, others can maintain ecosystem processes.
- Thresholds and Tipping Points: Non-linear changes where small perturbations lead to large-scale regime shifts.
Case Study: Ancient Stability and Geological Survival
The concept of resilience is not limited to rapid recovery from acute shocks but also encompasses long-term persistence through geological time scales.
- Daintree Rainforest Example:
- The Daintree Rainforest: Oldest Living Tropical Ecosystem, Ancient Biodiversity, and Geological Survival serves as a critical example of deep-time resilience.
- As one of the oldest living tropical ecosystems, it has persisted through significant climatic and geological shifts, demonstrating how ancient biodiversity contributes to long-term ecosystem stability.
- Its survival highlights the role of geological context in maintaining habitat continuity, allowing for the preservation of lineages that might otherwise be lost in younger, more volatile ecosystems.
Mechanisms of Resilience
- Functional Redundancy: Multiple species performing similar roles.
- Modularity: Compartmentalization of interactions to prevent cascade failures.
- Feedback Loops: Positive feedbacks that reinforce stability (e.g., nutrient cycling).
- Memory: Ecological memory via seed banks, soil microbiomes, or long-lived species.
References
- Daintree Rainforest: Oldest Living Tropical Ecosystem, Ancient Biodiversity, and Geological Survival