Beneficial effect of climate change on wheat yield and water footprints in the Middle-Manyame sub-catchment, Zimbabwe
Climate change is a major concern in wheat agroecosystems as it can affect productivity and crop water use. This study used the AquaCrop model to evaluate climate change impacts on the wheat yield, crop water use and water footprint of wheat production in the Middle-Manyame sub-catchment of Zimbabwe...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
IWA Publishing
2022-08-01
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| Series: | Journal of Water and Climate Change |
| Subjects: | |
| Online Access: | http://jwcc.iwaponline.com/content/13/8/2895 |
| Summary: | Climate change is a major concern in wheat agroecosystems as it can affect productivity and crop water use. This study used the AquaCrop model to evaluate climate change impacts on the wheat yield, crop water use and water footprint of wheat production in the Middle-Manyame sub-catchment of Zimbabwe. Climate scenarios were based on simulations from the NCC-NorESM1-M, CCCma-CanESM2 and MOHC-HadGEM2-ES General Climate Models downscaled using three Regional Climate Models (RCA4, RegCM4 and CRCM5) under two Representative Concentration Pathways (RCP4.5 and RCP8.5). The results showed that, compared to the baseline climate (1980–2010), yield may increase by 22.60, 29.47 27.80, and 53.85% for the RCP4.5 2040 s, RCP4.5 2080 s, RCP8.5 2040 s and RCP8.5 2080 s scenarios, respectively. Crop water use may decrease by 1.68, 1.25, 3.7 and 6.47%, respectively, under the four scenarios, respectively. Consequently, the blue water footprint may decrease by 19, 23, 24 and 38%, respectively, under the four scenarios. Sensitivity analysis attributed the increase in yields and the decrease in crop water use to the CO2 fertilization effect, which had a dominant effect over high-temperature effects. The results suggest that future wheat yields could be enhanced while crop water use is reduced because of climate change. However, the realization of these benefits requires farmers to adapt to climate change by adopting recommended agronomic practices and farm input rates that are consistent with those used in the modelling approach of this study.
HIGHLIGHTS
Influence of climate variables consumptive water footprint (WF) of wheat was analysed first time for Zimbabwe.;
A beneficial increase in wheat yields and decrease in the blue WF was predicted over Middle-Manyame sub-catchment.;
Increase in yield is due to the [CO2] fertilization effect.;
The study confirms the local occurrence of the ‘evaporation paradox’.;
Realization of the beneficial effects on adaptation to climate change.; |
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| ISSN: | 2040-2244 2408-9354 |