Calibration and validation of the AquaCrop model for the soybean crop grown under different levels of irrigation in the Motopiba region, Brazil

Abstract

The water-driven AquaCrop model to simulate yield response has been calibrated and validated for soybean cultivated under different water levels irrigation in Matopiba region, Brazil. The crop was submitted to seven irrigation treatments during the dry season and a dry treatment in the rainy season. The model was parameterized and calibrated by using soybean yield data collected at field level. Model performance was evaluated by using the following statistical parameters: prediction error (Pe), Nash-Sutcliffe efficiency index (E), coefficient of determination (R2), mean absolute error (MAE), root mean square error normalized (RMSEN) and Willmott’s index (d). The statistical analyses of the AquaCrop model calibrated for the Matopiba region disclosed error acceptable for yield prediction of soybean grown under tropical climate conditions. Results also indicated that the C2 soybean cultivar is more resistant to water stress than the C1 soybean grown in the Matopiba region, Brazil. In the treatments when the crop was well supplied with water, at least in one phase, the yield was greater than those with drought stress at last in one phase.

Soybean yield in the Matopiba region under climate changes

“…These results also indicate that the model has better performance in the simulation for the condition of no water deficit throughout the soybean cultivation cycle or in only one development stage. Similar results were obtained by Silva et al (2018) when they calibrated and validated the AquaCrop model to obtain soybean yield under different irrigation depths in the geographic region of Matopiba. Table 4 presents the CO 2 concentration and soybean yield for average medium-term period (2045/2046 and 2055/2056) and long-term period (2075/2076 and 2094/2095), compared with the current scenario, projected by the models HadGEM2-ES and MIROC5 under the scenarios RCP 4.5 and 8.5 in the study area.…”

“…Further details of the methodological procedures of the AquaCrop model can be found in Silva et al (2018). The AquaCrop model was calibrated and validated for the MATOPIBA geographic region using as input the daily data of the elements of climate (maximum and minimum air temperatures, maximum and minimum air relative humidity, rainfall, wind speed and solar radiation), crop, soil and field management collected from two field experiments, installed in the experimental area of the Universidade Federal de Tocantins (UFT), on the campus of Palmas, Brazil.…”

“…Grain production in the Matopiba region already represents 12.8% of the total production in Brazil, with soybean as the main grain and also the one with highest profitability, where much that is produced is intended for export. According to data from Brasil (2015), soybean production has significantly increased in the four states comprising the Matopiba region, with increments of 26.4% in Bahia,23.1% in Piauí,13.5% in Maranhão and 20.2% in Tocantins,Brazil. The possible climate changes projected for the 21 st century could significantly alter agricultural production, biodiversity and water resources, because with the warming evaporation will increase and water availability will decrease as the stored water is removed from the soil, generating a greater water deficit (Silva et al, 2018). Climate change can significantly alter crop production (FAO, 2012) because it will probably be accompanied by an increase in air temperature due to the increase in the concentration of carbon dioxide (CO 2 ), directly influencing the development, growth and yield of agricultural crops (Fagundes et al, 2010).…”

“…The capacity of the AquaCrop model (Raes et al, 2009;Steduto et al, 2009) to simulate the yield of different crops has been tested by several researchers worldwide: wheat in Siberia (Stricevic et al, 2011), cotton in the USA (Baumhardt et al, 2009), barley in Ethiopia (Araya et al, 2010); maize in Portugal (Paredes et al, 2015); soybean in Lebanon (Abi Saab et al, 2014) and in the Matopiba region, Brazil (Silva et al, 2018). In the context of the economic importance of soybean for the Matopiba region, it is imperative to conduct research studies addressing water use, taking into account the current pressure of agricultural practices on the water resources of this region through climate change scenarios.…”

Evaluation of Aquacrop Model in Simulating Bitter Gourd Water Productivity Under Saline Irrigation

“…This model has been used globally for crop growth modelling for different crops under diverse agro‐ecological conditions (Rezaverdinejad et al, ; Tavakoli et al, ). The AquaCrop model is an important tool with a major focus on increasing the number of irrigated zones and water consumption (da Silva, ). Recognizing the capabilities of AquaCrop, different research studies have assessed its application for the development of irrigation approaches (Linker et al, ; Linker and Ioslovich, ; Umair et al, ; Ojeda et al, ).…”