Understanding factors influencing farmers' crop choice and agricultural transformation in the Upper Vietnamese Mekong Delta

CONTEXT: The Vietnamese Mekong Delta (VMD) is an Asian mega -delta which is vulnerable to climate change and sea level rise, and is undergoing demographic change. Farmers are encouraged to shift from rice monocultures to more diversified and flood -based cropping options to adapt to climate change, lessen negative environmental impacts and manage labour productivity. However, this transformation takes place slowly, especially in the flood -zone areas of the Upper VMD. There is currently limited understanding of farmers' complex decision -making that considers the dynamic interactions between farmers, socio-economic circumstances and biophysical environments in this sub -region. OBJECTIVE: The objective of this study was to investigate the key factors driving farmers' decisions to switch between rice monocultures and other flood adaptive crops, and to provide lessons learnt and policy recommendations for sustainable and resilient agricultural transformation in the Upper VMD. METHODS: The study developed an agent -based model to simulate individual decision making in the Upper VMD. The model was parameterised with secondary data on social, policy, economic and biophysical drivers and validated by comparing the simulation results with real data in the baseline. Sensitivity analyses were conducted to gain insights into influencing factors. RESULTS AND CONCLUSIONS: The agent -based model shows that when farmers seek profit maximisation, the most influential determinants of their crop choice are high dyke construction, farmers' risk preference, perceptions of environmental sustainability, knowledge and market access of new alternatives, and labour availability. Considering the current context where the majority of farmers depend on high dykes, the transition away from rice monocultures and high dyke cropping systems, as envisaged by the Government, needs to occur gradually over an extended period and be contingent on a combination of measures that help implement existing policies at the local level. This includes discouraging high dyke construction; innovative extension services to raise farmer awareness of environmental sustainability and potential flood -adaptive cropping alternatives; targeted policies and actions for risk averse farmers; and market -based solutions to improve market access and mechanisation. SIGNIFICANCE: This study contributes to the current discourse on sustainable and resilient agricultural development in the VMD. The agent -based model provides insights into the farmers' crop choices in the flood zone and factors influencing their choices. These are important inputs for locally targeted policy planning and implementation.