From the article, Los camellones alrededor del lago Titicaca, by Pierre Morlon, 2006, a bofedal is an artificial wet area used for cultivation, such as the qochas.
The site Atlantisbolivia.org is reporting an interesting image from Google Maps of bofedales near Lake Poopo, Bolivia. The site is telling "...it may not be realised on the ground, but these satellite images show that these ponds were at one time artificially constructed in rows, with interlinking small channels in the Pampa Aullagas region of the Altiplano. On the Altiplano there are many such examples of this type of landscape, some natural, some artificial as above, which are known asbofedales (wetlands)."