What did the incas do to prevent erosion?

The Incas had a special concern to find ways to improve soil conditions for agriculture. The variety of the climate and the difficult territory, led them to look for different solutions, and there were many ways that they found to face the problem. Among the best known measures are the construction of platforms, which during the Inca government was given great importance. Although they demanded to mobilize large amounts of labor, which the Inca state could carry out relatively easily.

The platforms are artificial agricultural terraces that serve to obtain useful land for planting in the Andean slopes. They allowed to take better advantage of the water, both in rain and in irrigation, making it circulate through the channels that communicated their different levels, with this measure they avoided at the same time the hydraulic erosion of the soil. The platforms not only served for the cultivation of corn, but for the cultivation of different agricultural products, and even for different uses: for sowing, to avoid erosion, for the washing of mineral salt.

i believe it d) heterogeneous

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