Performance of pre-hispanic irrigation systems in the Andean region of Bolivia

Abstract

In the area that is today Bolivia, the pre-Hispanic era was a period of great learning, marked by the management and use of natural resources, where farming became one of the cornerstones of production and where irrigation was an essential practice. In different areas, pre-Hispanic surface irrigation methods are still in use today, such as kanis irrigation and zigzag corrugated furrow irrigation. The primary aim of this paper is to compare the performance of the above irrigation systems using a potato crop at the Choquenaira Experimental Farm located at an altitude of 3877 m above sea level. During the growing cycle, there were seven irrigation events for each system.With kanis irrigation, the advance times were very short due to the high flow rates and the shortness of the furrows. As a result, there were no major variations in the opportunity time. The volume of water applied per hectare during the growing cycle was 1315m3, while the crop-water requirement was estimated at 1854m3/ha. The application efficiency of irrigation varied from 18% to 100%, with deficit irrigation in three events.In the case of zigzag corrugated furrow irrigation, the advance times were higher due to the greater length of the furrow. The total volume of water applied was 2595 m3/ha while the calculated crop-water requirement was 2644m3/ha, thus quite similar. The application efficiency of irrigation varied from 18% to 91.3%, with deficit irrigation and high values of surface runoff.The time required for irrigation, and by extension the labour required, is greater for the kanis irrigation system, which is consequently regarded as more suited to small areas of land. The yield of potato tubers was larger using the kanis method compared to the zigzag furrow irrigation method due to the more efficient use of water.