Analysis of climate change effects on crop water availability for paddy, wheat and berseem

Climate change has been a serious concern in the 21st century and mitigation strategies on its effects are less researched. The increase in temperature and changes in rainfall have forced researchers to ponder over reducing the wastage of fresh water. This paper deals with the rain water availability and the crop evapotranspiration (ETc) changes occurring and projected to occur over a time period of fifty years. Three major crops, paddy, wheat and berseem fodder were considered for three locations. Observed data and forecasted data for precipitation and temperature was obtained from India Meteorological Department and Can Esm2 model respectively. The Mann-Kendall (MK) test and the Thiel-Sen's Slope estimator (TSS) test were applied on the crop stage wise aggregated rain water available and the ETc to analyze the effects of climate change. In addition to the above study, the historical and projected means of crop period wise aggregated effective rainfall, total net irrigation requirement and total crop water requirement for a range of dates of sowing/transplanting for the above mentioned crops and locations were analyzed. It was seen by the analysis that the rainwater availability is seen to decrease and the temperatures increase with a delay in the sowing dates in the future scenarios causing an increase in the crop water requirements. Suitable shifting of the crop sowing or transplanting dates is seen to aid to better exploit the available rainwater and minimize the irrigation application.