Which of the following is not a characteristic of alley cropping systems that are being studied as one alternative to slash-and-burn systems?
A) The woody border plants help conserve water in the cropped alleys by shading the soil.
B) Organic mulch cut from border plants helps control weeds and prevents runoff and erosion.
C) Food crops are grown in alleys with borders provided by woody species.
D) Crop yields in humid regions have generally been satisfactory using this system.
E) Nutrients accumulated from subsurface soil layers by the border plants are added in residues to the surface of the cropped areas.
Question 2
Which of the following is not a likely component of the ecology-based paradigm for future intensified U.S. food production?
A) pest management systems that minimize the use of chemical pesticides
B) organic-inorganic combinations that build active soil organic matter
C) rotation systems that enhance biological diversity
D) increased rates of nitrogen fertilizer to reduce deficiencies of this element
E) All of the above are unlikely.
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