Which agricultural technique deployed by pre-Columbian civilisations prevented soil erosion on steep Andean slopes?

💡 Explanation

When slopes are cultivated, terrace farming creates level plots with retaining walls because gravity pulls soil downwards, initiating erosion, and the walls mechanically counteract this force. Therefore terrace farming effectively prevents soil loss, rather than chinampas, slash and burn or aqueducts which serve other pursposes like enhanced growing conditions or irrigation.

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