Which soil degradation effect most directly threatens the sustainability of ancient terrace farming in the Andes?

💡 Explanation

When terraces lack adequate drainage, water accumulates, increasing hydraulic pressure and mobilizing soil particles downwards, leading to the terraces collapsing as erosion worsens. Therefore, erosion ruins these agriculture platforms, rather than increasing salt from irrigation, lacking of nutrients from washing by rainfall, or pressure from land animal activities.

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