Simulation of quinoa production in the Bolivian highlands with the aquacrop model with future scenarios generated by LARS-WG and QPM

Gavi Alavi; Jan Diels; Patrick Willems; Magali García Cárdenas

Abstract

The Altiplano of Bolivia is a semi-arid to arid region with adverse conditions for agriculture (4000 masl). Quinoa (Chenopodium quinoa Willd.), A highly nutritious food, is well adapted to the unfavorable conditions of the Altiplano. The present study aims to determine the impact of climate change on quinoa in three locations in the Bolivian highlands (Viacha, Patacamaya and Río Mulatos). Two downscaling methods were used to generate future climate scenarios (SREs and RCPs): LARS (scenarios B1, A1B and A2 for SRE) and QPM (scenarios 4.5 and 8.5 for CPR). Precipitation, maximum and minimum temperature were generated for three different periods (2030s, 2050s and 2090s). To estimate the productivity of quinoa, the AquaCrop model was used. Among the results is that the maximum and minimum temperatures are increased more in RCPs than in SREs, for the years 2030s and 2090s. Monthly precipitation did not show significant changes during the dry season. The number of days with frost is reduced. Likewise, the probabilities of periods of frost that can damage quinoa (-3 ° C) would be reduced. AquaCrop estimates that the average cycle would be reduced in all locations and scenarios. In addition, they indicated that if the conditions of management in the field (irrigation to dry land, low fertility, etc.) are similar to the current ones the production does not vary much for SRE. However for RCPs, in Patacamaya and Rio Mulatos the production would be reduced in a range of 0.1 to 0.2 Mg ha^-1. Finally, in Patacamaya and Río Mulatos it is expected that the loss of production due to water stress will increase and in Viacha there will be a slight decrease in water stress. Positive and negative effects on quinoa are expected in the Bolivian highland.