Assessment of the climate-change impacts and evaluation of adaptation measures for paddy productivity in Quang Nam province, Vietnam
This study investigates the impacts of climate change on winter and summer paddy yields and evaluates adaptation measures in order to overcome the projected impacts of climate change in Quang Nam province of Vietnam. Future climate-change scenarios for the periods of 2020s, 2050s and 2080s were projected by downscaling the outputs of HadCM3 general circulation model for the two selected IPCC SRES A2 and B2 scenarios. The AquaCrop model was used to simulate the impact of future climate on paddy yield. The minimum and maximum temperatures of the basin are expected to increase by 0.35–1.72 and 0.93–3.69 °C, respectively in future. Similarly, the annual precipitation is expected to increase by 9.75 % in future. Results show that climate change will reduce paddy yield in winter season for both scenarios and all time periods, whereas an increase in the yield is expected in the summer season for 2020s and 2050s relative to baseline yield. The overall decrease in paddy yield in winter season can be offset, and paddy yield of summer season can be enhanced to potential level by altering the transplanting dates and by introducing supplementary irrigation. Late transplanting of paddy shows an increase in yield by 20–27 % in future, whereas supplementary irrigation in winter season paddy shows an increase in yield up to 42 % in future. The results of this study can be used by policy makers and key stakeholders to optimize paddy production under changing climate regimes in Quang Nam province of Vietnam.