Precipitation probability and water budgeting for crop planning in central Gujarat

Abstract

The rainfed agriculture is highly inconsistent due to temporal distribution of precipitation during the critical stages of crop growth leading to crop failure. The large spatial and temporal variation in precipitation distribution is observed in central Gujarat (Vaidya et al., 2008). The precipitation in Gujarat varies from 300 mm in the north and north-west to gradually increasing to 2500 mm in the Southern districts (Priyan, 2015). The spatial and temporal variability of precipitation is compounded due to increase in frequency and intensity of extreme precipitation events due to global climate change (Ghosh et al., 2012). The analysis of daily, weekly, monthly and seasonal precipitation of a region is useful in designing of water harvesting structure, decision for agricultural operations like field preparation, sowing, irrigation, fertilizer application etc. (Sharma et al., 1979). To optimize agricultural productivity in any region, there is an urgent need to quantify temporal precipitation variability as a first step of combating extreme effects of persistent dry spells and crop failure (Kumar et al., 2014). The weekly water budget indirectly indicates the length of assured moisture availability for growing crops in the region (Singh et al., 2013). Therefore, keeping the above mentioned facts in mind, an attempt is made to analyze the daily precipitation data of sixty years at Vasad for initial, conditional and consecutive dry and wet week probability, weekly precipitation at different probability, monthly, seasonal, annual variations of precipitation and weekly soil water budget for crop planning in central Gujarat.