Impacts of Site-Specific Nutrient Management in Irrigated Rice Farms in the Red River Delta, Northern Vietnam

This study estimates the impact of the adoption of SSNM practices on rice production of smallholder farmers in Vietnam using cross-section household data (n = 371) gathered from the provinces of Ha Nam and Ha Tay in the Red River Delta. Specifically, it investigates the economic impact of SSNM, focusing on SSNM-induced changes in the yield, profit, nitrogen use and pesticide use of farmers. The instrumental variables (IV) approach is used to achieve this objective because it deals with endogeneity and self-selection bias present in the study. SSNM improves the paddy yield of farmers by 0.6 tons per hectare and profit by $150 per hectare. It has no statistically significant effect on the amount of pesticide and nitrogen use of farmers. The higher profits for adopters versus non-adopters of SSNM arise from increased grain yield rather from reducing fertilizer costs and pesticide costs. Results of the impact analysis identified several directions that can be pursued to improve further the adoption of SSNM.