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Ecosystem size determines food-chain length in lakes
D M Post1, M L Pace, N G Hairston
1Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York 14853, USA. dmp18@cornell.edu
Nature
|July 13, 2000
Summary
Ecosystem size, not productivity, determines food-chain length in natural systems. This finding impacts understanding of ecological communities and contaminant levels in predators.
Area of Science:
- Ecology
- Ecosystem Dynamics
Background:
- Food-chain length is a key ecological characteristic influencing community structure and contaminant bioaccumulation.
- Previous hypotheses on food-chain length determinants (productivity, ecosystem size) lack robust empirical support.
Purpose of the Study:
- To empirically test the productivity hypothesis, ecosystem-size hypothesis, and productive-space hypothesis for food-chain length.
- To determine the primary drivers of food-chain length in natural ecosystems.
Main Methods:
- Comparative analysis of food-chain length across various natural ecosystems.
- Statistical testing of relationships between food-chain length, ecosystem size, and productivity.
Main Results:
- Food-chain length significantly increases with ecosystem size.
- No significant relationship was found between food-chain length and ecosystem productivity.
Conclusions:
- Ecosystem size is the primary determinant of food-chain length, contradicting hypotheses focused solely on productivity.
- Findings suggest ecosystem size influences resource availability and habitat complexity, thereby shaping food-chain structure.
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