Assessing the Effects of Drought on Rice Yields in the Mekong Delta

In contrast to other natural disasters, droughts may develop gradually and last for extended periods of time. The World Meteorological Organization advises using the Standardized Precipitation Index (SPI) for the early identification of drought and understanding of its characteristics over various geographical areas. In this study, we use long-term rainfall data from 14 rain gauge stations in the Vietnamese Mekong Delta (1979-2020) to examine correlations with changes in rice yields. Results indicate that in the winter-spring rice cropping season in both 2016 and 2017, yields declined, corresponding with high humidity levels. Excessive rainfall during these years may have contributed to waterlogging, which in turn adversely affected yields. The results highlight that not only drought, but also humidity has the potential to adversely affect rice yield.

Automated summary

Compared to other natural disasters, droughts have a gradual development and longer duration. The World Meteorological Organization suggests using the Standardized Precipitation Index (SPI) for early drought identification and understanding its characteristics in different geographical areas. This study analyzes long-term rainfall data from 14 rain gauge stations in the Vietnamese Mekong Delta (1979-2020) to examine its correlation with rice yield changes. The results show that in the winter-spring rice cropping seasons of 2016 and 2017, there was a decline in yields, which corresponds to high humidity levels. Excessive rainfall during these years may have caused waterlogging, negatively impacting yields. The findings emphasize that not only drought, but also humidity can have detrimental effects on rice yield.