Broadly inflicted stressors can cause ecosystem thinning

Area of Science:

• Ecology
• Environmental Science
• Theoretical Ecology

Background:

• Anthropogenic stressors like habitat destruction and pollution broadly impact species mortality and fecundity.
• Ecological communities face threats from climate change, invasive species, and harvesting.

Purpose of the Study:

• To investigate how broadly inflicted stressors affect interspecies competition and ecosystem structure.
• To model the consequences of these stressors on functional redundancy and ecosystem stability.

Main Methods:

• Four analytical models of interspecies competition were developed.
• The models examined the effects of broadly inflicted stressors on species with similar ecological niches.

Main Results:

• Broadly inflicted stressors disproportionately cause competitive exclusions among ecologically similar species.
• Ecosystems become functionally thinner (less redundant) as stressor intensity increases.
• Stressors can indirectly cause extinctions at lower intensities than direct impacts, driven by species interactions.
• Hydra effects may occur, where higher stressor intensity increases the abundance of less sensitive species.

Conclusions:

• Ecosystems under stress may lose functional redundancy and temporal stability.
• While productivity might be buffered by favoring less sensitive species, overall ecosystem resilience is compromised.
• Understanding species interactions is crucial for predicting extinction dynamics under anthropogenic stress.