Which long-term constraint faced chinampa agriculture concerning continuous maize cultivation?

💡 Explanation

In chinampas, intensive maize cultivation without adequate nutrient replenishment caused depletion of essential elements like nitrogen and phosphorus, reducing long-term soil fertility because of nutrient uptake by the crop. Therefore declining soil fertility posed aconstraint, rather than increased pests, rising water tables, or decreased sunlight, which depend on factors beyond soil nutrient depletion.

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