On the Andean highlands, the "qochas" are lakes or ponds of natural or artificial origin. An ancient agricultural technique is based on their use. Linked together by a network of canals, qochas form a system of water and soil management, alternately used for crops or pasture. The concave structure of qochas controls the strong evaporation produced by solar radiation and wind blowing. Qochas can be observed in the satellite imagery of Google Maps.
Cite
@article{arxiv.1104.4748,
title = {Qochas on Andean highlands},
author = {Amelia Carolina Sparavigna},
journal= {arXiv preprint arXiv:1104.4748},
year = {2011}
}