Climate change assessment and its impact on paddy production in Kottayam district of Kerala

The present paper analysed climate change overtime occurred for a period of 30 years in Kottayam district of Kerala and its impact in productivity of paddy. Trend analysis was performed using non-parametric Mann-Kendall test and Sen’s slope estimator for annual and different seasons. The results indicated a significant decreasing trend in annual and north east monsoon rainfall with an increase in north east and south west monsoon maximum temperature. For minimum temperature a negative trend was noticed for all seasons except summer and winter. Multiple linear regression performed to determine the impact of climate change in the paddy production showed maximum temperature in August, minimum temperature in June had positive and significant effect on Virippu paddy production in Kottayam. While the rainfall during July had a negative significant effect, indicated that excess rainfall during July adversely affect the paddy production during Virippu season. However, maximum and minimum temperature during October had a positive significant effect on the production of Paddy for the Puncha crop. Excess rainfall during October and November had a negative significant effect on Paddy production. High temperature especially night temperature have a positive impact on paddy during it's vegetative phase and excess rainfall have negative impact during reproductive phase of the crop.