Drought Analysis of Southern Part of Chhattisgarh Agro-Climatic Plain Zone: A Case Study of Bilaspur District
Vijay Singh1,* and R. K. Isaac1
1,*Department of Soil and Water Conservation Engineering
Allahabad Agricultural Institute-Deemed University, Allahabad
Rainfall data of 20 years (1982-2001) based on standard weeks was analyzed for Bilaspur District of Chattisgarh State. The earliest dates of monsoon periods were determined along with their deviations from the mean value. The frequency of dry and wet weeks was calculated by using the concept developed by Pandarinath by considering 20mm rainfall in a week as a demarcation line. Dry and wet spells in pre monsoon, monsoon, and post monsoon periods were estimated by using Markov Chain Model. The monthly maximum rainfall at different probability levels was calculated by using Gumble Probability Method. It was observed that there were 23 dry weeks in pre monsoon and 19 wet spells in monsoon at 0.75 probability density, which was found in close proximity with the observed rainfall for the year 2001. The estimation of deficit periods showed that there was a need of irrigation water especially in the 20th to 23rd weeks and 30th to 33rd weeks after transplanting of paddy crop. Moisture deficit periods were calculated by comparing the mean monthly evapo-transpiration values with the mean monthly rainfall values of Chhattisgarh.
