3B Review Sheet

Real world food webs have high diversity and connectance but short food chains (3-4 trophic levels)
Reasons:

• Energetic limitations (10% trophic transfer efficiency=
• Stability 

Diversity enhances stability
       Empirical evidence:

• Tree hole experiment
• Grassland experiment-plant different number of species on each plot. Plots with more types of plants were more stable

What does it mean if a is positive?
The other species is helping the species grow