Use of Markov Chain for Dry and Wet week Analysis for Crop Planning at Aduthurai, Tamil Nadu, India

Knowledge of rainfall occurrence pattern is very important for making decision on crop planning and soil water conservation studies. Markov chain probability model was used to enlighten the long term frequency behavior of wet or dry weather spells during the main rainy season. This study used 35 years (1981-2015) of rainfall data and aggregated weekly rainfall data (52 weeks) was considered as standard week to study the probability of occurrence of wet and dry weeks. The probability of occurrences of initial and conditional probability is more than 50 % on 35 th week with threshold limit of 20 mm per week. Therefore the land preparation for sowing or planting could be undertaken in 35 th week respectively for the main rainy season crop cultivation. Study area dominated by North East Monsoon with mean annual rainfall of about 1100 mm. At Aduthurai region there is more chance for intermittent wet spell and hence drought resistant short duration pulse may be suggested. In addition, this analysis can be very helpful in identify the cropping pattern including cropping and intercropping system during that period.