COMPUTATION OF WATER DEFICIT AND ARIDITY INDEX FOR THE PURVANCHAL

The crop water requirement defers the quantity of water needed to meet the water losses through evapo-transpiration, potential evapo-transpiration, disease free under non-restricting soil conditions. The basic requirement of water is function of the soil moisture deficits as influenced by evapo-transpiration and soil and plant characteristics. Keeping this in view an experiment has been conducted to estimate the evapo-transpiration, potential evaporation and aridity index for the region of Faizabad distt. of Uttar Pradesh. Due to uneven and inadequate distribution pattern of rainfall in district, there is a need to computing the water deficit for planning of supplemental irrigation through which frequent failure of crops can be controlled, along-with to increase the water use efficiency under limited resources. The climatic data of 10 years (i.e. from 1999-2009) were recorded and analyzed by Thornthwait (1948) method to compute ets the water defit. On the basis of data analyzed the result revealed that the average potential evapo-transpiration, evapo-transpiration, water deficit and aridity index were found to be 1572.60 mm, 24.74 mm, 8.08 cm, and 0.82 respectively.