Spatio-temporal analysis of the climate impact on rice yield in north-west India

Abstract

The effects of climate, fertilizers and irrigation on rice yield and spatial variations of growing season climatic variability were analyzed in the three regions (North-west, Central and South-west) of Indian Punjab from 1974 to 2013. There was a linear increase in rice yield in Punjab (30 kg ha−1 year−1 in north-east, 29 kg ha−1 year−1 in central and 34 kg ha−1 year−1 in south-west region) over 40 years. The results of Mann-Kendall test and Sen’s slope estimator showed an increase in minimum temperature (0.03 °C year−1 in North-east Punjab and, 0.04 °C year−1 each in Central and South-west Punjab) but no significant trend in maximum temperature and rainfall during the rice growing season (June–September). Among different climatic and technological variables, 49% of the variance in rice yield was explained by minimum temperature. Irrigation explained 33% of the remaining 51% variance in rice yield. The larger effect of climatic variables than fertilizer and irrigation suggest that adoption of climate smart and water conservation technologies are required to reduce rice yield variability in the future and improving food security. Spatial variations in yield, rainfall and temperature across Punjab were substantial and these have important consequences for food security by indicating the need for region-specific technologies.