Comment on the relative advantages and disadvantages of organic versus plastic mulches. What does conservation tillage conserve? How does it do it? Explain under what circumstances earthworm channels...

Comment on the relative advantages and disadvantages of organic versus plastic mulches. What does conservation tillage conserve? How does it do it?

Explain under what circumstances earthworm channels might increase downward saturated water flow, but not have much effect on the leaching of soluble chemicals applied to the soil.