T2 – Extreme events impacts on rice production in the Mekong River basin

Short description

Climate change is increasing the occurrence and severity of extreme events such as droughts and heatwaves, with significant consequences for agricultural production. Cropping systems are particularly vulnerable to these stresses, as both water shortages and extreme temperatures can substantially reduce plant development and yields, especially when they occur during sensitive growth stages. This challenge is especially critical in the Mekong River basin, where rice cultivation is of major importance for regional livelihoods, food security, and the broader agricultural economy, and where production is strongly influenced by climatic and hydrological variability [1].

This thesis aims to investigate the impacts of drought and heatwave events on rice production in the Mekong River basin through an integrated modelling approach. A drought and heatwave generator will be used to develop synthetic extreme-event scenarios spanning a range of plausible stress conditions [2]. These scenarios will then be used within the VIC-Res hydrological model [3] to quantify changes in water availability and within the AquaCrop crop model to assess the resulting impacts on rice growth and yield. By combining hydrological and crop modelling under synthetic extreme conditions, the thesis aims to improve the understanding of how compound climate stresses propagate through water resources and agricultural systems, ultimately affecting rice production in the basin.

PROPOSED ACTIVITIES

Literature review

  • Review the literature on climate change impacts on agriculture, with particular focus on droughts, heatwaves, and compound extreme events.

Scenario development and model implementation

  • Analyze historical records of droughts and heatwaves in the Mekong River basin.
  • Develop synthetic drought and heatwave scenarios representing a wide range of plausible extreme conditions through perturbation of historical events.
  • Run VicRes and Aquacrop under both historical forcings and the generated synthetic scenarios.

Impact assessment and discussion

  • Assess the impacts of synthetic drought and heatwave events on water availability and rice yields through the integrated hydrological and crop modelling framework.
  • Investigate the sensitivity of rice production to different characteristics of extreme events, such as intensity, duration, and timing during the growing season.
  • Assess the added value of irrigation during extreme events compared with rainfed conditions.

REFERENCES

  1. Kang, H., Sridhar, V., Mainuddin, M., & Trung, L. D. (2021). Future rice farming threatened by drought in the Lower Mekong Basin. Scientific reports, 11(1), 9383. https://doi.org/10.1038/s41598-021-88405-2
  2. Zaniolo, M., Fletcher, S., & Mauter, M. (2024). FIND: A synthetic weather generator to control drought frequency, intensity, and duration. Environmental Modelling & Software, 172, 105927. https://doi.org/10.1016/j.envsoft.2023.105927
  3. Eldardiry, H., Mahto, S. S., Fatichi, S., & Galelli, S. (2025). VIC-Res Mekong: An open-source hydrological-water management model for the Mekong River basin. Environmental Modelling & Software, 106603. https://doi.org/10.1016/j.envsoft.2025.106603

Relevant courses and knowledge

Advanced Environmental Systems Analysis

Number of students

1/2

Requisites

The student should be comfortable with data handling and programming (Python).