Multiple Stressors Simplify Freshwater Food Webs.

Area of Science:

• Ecology
• Environmental Science
• Aquatic Ecosystems

Background:

• Freshwater ecosystems face numerous anthropogenic stressors.
• Understanding stressor interactions on food web structure is limited.
• Common stressors include warming, nutrient loading, and pollution.

Purpose of the Study:

• To investigate the combined effects of warming, nutrient loading, and insecticide pollution on shallow lake food web structure.
• To quantify single and interactive stressor impacts on network properties.

Main Methods:

• Large-scale mesocosm experiment simulating shallow lake conditions.
• Quantification of food web network structure under different stressor combinations.
• Analysis of energy transfer pathways and biomass distribution.

Main Results:

• Identified antagonistic and synergistic stressor interactions affecting feedback loops.
• Observed simplification of food web structure and elongated energy pathways.
• Shifted biomass distribution from benthic to pelagic pathways, increasing turbid state risk.

Conclusions:

• Multiple anthropogenic stressors interact to disrupt freshwater food web structure.
• These disruptions can lead to ecosystem regime shifts, impacting management strategies.
• Results are crucial for understanding and managing aquatic ecosystems under global change.