Vol. 11, Special Issue 10 (2022)

Author(s):
M Mahanty, S Samantaray, A Priyadarshini, AKB Mohapatra and BS Rath

Abstract:
Investigation of trends and variability in rainfall patterns is of paramount importance for the effective planning and management of rain fed cropping systems. A detailed analysis was carried out to understand the changes in rainfall patterns and characteristics at a regional scale on agro-climatic zone basis, in North central plateau zone (Keonjhar and Mayurbhanj dist.) of Odisha. This study found that mean annual rainfall of North Central Plateau zone is 1450 mm, with an average of 67 rainy day. CV of annual rainfall of different blocks varies between 20-37%. This zone receives 63% & 67% of mean annual rainfall during SW monsoon in Keonjhar and Mayurbhanj district respectively. The Mann–Kendall (MK) test was used for the analysis of increasing and decreasing (monotonic) trends. It was also observed that annual rainfall in some of the blocks showing increasing trend and others are found to have significant decreasing trends in the magnitude of rainfall during the non-monsoon season. At 75% probability this zone received 1150 mm rainfall, which is good amount of rainfall for crop production. Mean annual maximum temperature of this zone was 31.5 °C and minimum temperature was 20 °C. Monsoon starts effectively from 22^nd week (9 June to 15 June) in North central plateau zone and remain active up to 41^th week (9^th October to 13^th October). Rice nursery bed preparation can be started by 22^nd SMW and harvesting operation can be completed by 38^th-42^nd week by selecting medium to long duration varieties. On upland and medium lands, early sowing of pre-rabi crops like cow pea, horse gram, green gram, black gram, Niger, tomato, cabbage, cauliflower, okra, and leafy vegetables to be done to conserve soil moisture.