Which outcome occurred when pre-Columbian civilizations over-cultivated terraces on steep Andean slopes?

💡 Explanation

When terraces were over-cultivated, soil erosion occurred because the lack of fallow periods and vegetation cover meant reduced soil cohesion leading to topsoil loss. Therefore nutrient depletion resulted, rather than biodiversity increase, yield enhancement, or pest reduction, which require soil conservation.

• Which agricultural challenge did pre-Columbian chinampa systems primarily address in the Valley of Mexico?
• Which soil failure risk is MOST increased when rainfall intensity exceeds terraced field drainage capacity?
• Which risk increases with increasing tin quantities beyond optimal proportions during Bronze-Age copper smelting?
• Which outcome occurred due to improperly compacted aggregate base beneath typical Roman roads?
• Which risk most directly reduces structural lifetime of terrace farming retaining walls during seasonal torrential rains?
• Which outcome resulted from pre-Columbian Andean terrace farming during periods of heavy rainfall?