Food Web Similarity Increases With Productivity Similarity at a Continental Scale

Area of Science:

• Ecology
• Food web dynamics
• Biodiversity research

Background:

• Primary productivity is crucial for trophic interactions, but its influence on food web structure across continental scales remains unclear.
• Anthropogenic pressures pose a global threat to food web integrity, potentially leading to predictable disassembly.

Purpose of the Study:

• To investigate how plant productivity and anthropogenic fragmentation influence the similarity of food web networks.
• To assess these influences at both continental and regional scales across diverse ecosystems.

Main Methods:

• Analyzed food web structural equivalence for 127 protected areas, independent of species identity.
• Accounted for the scaling effects of species richness and connectance on food web structure.
• Compared food web similarity across sites with varying plant productivity and levels of anthropogenic fragmentation.

Main Results:

• Food webs exhibited significantly higher similarity at sites with similar plant productivity on a continental scale.
• Within woodland savannas and tropical rainforests, food web similarity was linked to similar levels of anthropogenic fragmentation.
• Empirical evidence demonstrates predictable patterns in food web structure related to environmental and anthropogenic factors.

Conclusions:

• Plant productivity is a key driver of continental-scale food web similarity.
• Anthropogenic fragmentation influences food web structure regionally, particularly in savannas and rainforests.
• Understanding these drivers is essential for predicting biodiversity and ecosystem function under environmental change.