Water balance studies for the crop planning in Ranchi, Jharkhand

Abstract

The rainfall data of 35 years was analyzed to quantify the rainfall efficiency for increased production for Ranchi region. The actual evaporation in driest year due to prolonged dry spell gives rise to severe drought condition affecting the crop growth adversely. No surplus water was recorded during driest year. In respect of coefficient of variation, the month of July registered the lowest coefficient of variation of 35 per cent followed by August (38 per cent) indicating lesser variability during this month. The threshold level of coefficient of variation ranges of 50-100 per cent was associated with April to October and indicated the dependability of rainfall in these months as compared to other months. The maximum length of growing season of 28 week, while minimum 12 week was recorded. In normal conditions, the length of growing season were recorded 18 week. Therefore, short duration paddy variety Birsa Gora-101, maize, i.e., Devki, Ganga-11, Suran and kharif pulses are suitable for the region.