Resumen
- Arracacha root is an upland crop, quite tolerant to water scarcity conditions, nevertheless, in cases of abnormal climate variability patterns the risk of drought and thus crop productivity loss gets higher. This study aimed to develop an adequate understanding of arracacha crop water management for irrigation purpose. Crop evapotranspiration (ETc) and crop coefficient (Kc) were determined based on water balance evaluation on a daily basis in volumetric lysimeter-scale experiments during the crop growing season. Meteorological data base of monthly temperature and precipitation, in Cajamarca (Tolima region, Colombia), from 1980 to 2011 were analyzed. Arracacha soil characterization was carried out in the region. Furthermore, crop water requirement and Net Irrigation Requirement were determined, using Cropwat model, for different hydrological years: Average, El Niño and La Niña. Results showed that total water consumption for arracacha root was 820 mm along the whole growing season. The development stage was the largest stage, nevertheless, the highest water consumption was registered at the Mid-stage which was 39.4 % of the total water consumption. Seasonal crop coefficients were 0.57, 0.72, 0.95 and 0.90 at Initial (Init), Development (Dev), Mid and Late stage, respectively. Furthermore, high yield reductions are expected in the Mid-stage if limited water is supplied. The proposed modeling framework could be recommended for arracacha farmers to select the most suitable scenario for better agricultural water resources management.