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1 Explain how the competitive exclusion principle and the unified neutral theory vary in explaining species coexistence.

2 How can we make use of physiological information such as photosynthetic pathway (e.g., C3 vs. C4) of component species in designing sustainable agroforestry systems?

3 Although shading is commonly associated with competition for light, shading can be beneficial in agroforestry systems. Describe the beneficial or facilitative role of shading with the help of examples.

4 What is meant by “safety‐net hypothesis” in an agroforestry context? Provide an example each from (a) alley cropping, (b) silvopasture, and (c) riparian buffer.

5 Agroforestry systems seem to have fewer pest problems than their monoculture counterparts. Explain the ecological basis of this phenomenon.

6 Describe the concept of hydraulic lift and its importance in improving the water balance of forage grass in a longleaf pine (Pinus palustris) silvopasture in the southern United States.

7 Explain how plants utilize root plasticity in avoiding belowground competition when grown in species mixtures.