Indian Journal of Soil Conservation

Weekly rainfall, onset of effective monsoon, withdrawal of monsoon, onset and duration of critical dry spells and (weekly pan evaporation at different probabilities have been analyzed using Doorenbos and Pruitt's modified equation for Panderpali-I micro-watershed in Baragaon block ofdistrict Sundargarh, Orissa. Rainfall events at 70 per cent and pan evaporation at 20 per cent probability of exceedance have been considered for crop planning in rainfed uplands for kharif and rabi seasons. The weekly consumptive use of kharif crops was estimated assuming average crop coefficient value as 1.0. The results revealed that the duration of monsoon period is 92 days and short duration crops of 90–95 days should be preferred to be grown in rainfed uplahds. There is chance of drought towards the middle of 28^th and last part of 33^rd week coinciding with the initial growth and flowering stages of most of the rainfed crops, respectively. Effect of drought can be overcome with provision of suitable conservation measures, in-situ and ex-situ storage of excess runoff water in ponds and tanks for supplemental irrigation at the time of need during kharif. If possible, one or two tank irrigations at flowering or seed formation stage will be beneficial to the crops grown under residual soil moisture during rabi after the harvest of kharif crops with mulching ofthe crop residues over the soil surface.