Investigating the relationship between climate change and Total Factor productivity growth of rainfed barley in Iran

The high dependence of developing countries on the agricultural sector and the impact of climate on the one hand, the technological and financial weakness of farmers on the other hand has doubled the importance of examining the relationship between climate change and agricultural productivity in these countries. The purpose of this study is to investigate the relationship between climate change and total productivity factor (TFP) growth of rainfed barley in Iran.

In this regard, first, the growth of rainfed barley TFP for major producing provinces in the period 1378-1397 was calculated using the Solo model and integrated data technique. Then, by calculating the standard precipitation index (SPI), the effects of climatic variables (average temperature, minimum temperature, maximum temperature and standard precipitation index) on TFP growth of rainfed barley were evaluated. Finally, using 18 climate change scenarios under HadCM2 and ECHAM4 models, TFP growth changes of rainfed barley were calculated.

During the study period, the average growth of rainfed barley TFP is positive and equal to 0.183. In addition, the average SPI index of major rainfed barley producing provinces indicates normal climatic conditions. Also in terms of climate, it varies between very severe drought and very high humidity. The study of the effects of climatic variables on the growth of rainfed barley TFP shows that the SPI index has a negative and significant effect and the minimum temperature has a positive and significant effect on the growth of rainfed barley TFP. Also, the growth rate of rainfed TFP due to climate change decreases by -0.08 on average.

According to the results, irregular rainfall at the wrong time can reduce the growth of TFP rainfed barley and on the other hand affect labor productivity. Due to the high sensitivity of rainfed barley to abnormal climatic conditions that reduce its productivity.