Effect of climatic factors on farm income of rain-fed and irrigated farming households in Vietnam

The paper provides new evidence of the effect of temperature and precipitation on crop profit of farmers applying different farming systems across different seasons as well as geographical regions in Vietnam for the period 2004-2016. The result finds that the effect of fluctuation in temperature and rainfall on the crop profit of farmers is not uniform across the three regions (North, Central and South) and also considerable variation across rain-fed and irrigated farms. For the rain-fed farming system, (i) rainfall in the dry season has a nonlinearly (boolean AND) association with the profit, but rainfall in the rainy season has no effect, and (ii) dry season temperature and rainy season temperature have, respectively, boolean AND-shaped and U-shaped relationship with the profit. For the irrigated farming systems, the temperatures in the dry season and rainy season have a U-shaped relationship with the profit. The findings show that the irrigated farming systems have been effective in the long term in the face of climate change. Therefore, in preparation for adaptation to climate change, the Vietnamese agricultural sector needs a complete irrigation system at both farm and regional levels.