Water Resources Management and Precession Irrigation in the Jordan Valley - Palestine: Case study Cucumber Crop

摘要

Agricultural sector in the West Bank consume about 65% of the available fresh groundwater resources, and this ratio rise to 85% in the area of the Jordan Valley, where intensive agriculture applied. Growing vegetables (tomato, cucumber,...) under green houses is a common practice in this semi arid area, where more than one crop cultivated during the year. Water from springs (free of charge) and low cost groundwater taped from shallow private boreholes (up to 100 m) provided farmers with their agricultural water needs, this condition make precession irrigation rare, and difficult to implement. In the other hand, scarcity of water and salinization of groundwater are major challenges facing the irrigated agriculture in the Jordan Valley Re-evaluating the irrigation practices, by applying precession irrigation is one components that will help to manage the available groundwater resources, and as consequence to sustain the agricultural activities in the Jordan Valley. The objective of this research was to evaluate the actual water required for growing cucumber under high plastic greenhouse condition. The actual water amount required for cucumber was estimated by using the FOA procedure which depends on the equation: Etc= K_c* E_(t0), where K_c is the adjusted crop coefficient for cucumber in greenhouses and E_(t0) is the daily reference evapotranspiration. The Etc-values are used later on according to the average daily values of E_(t0) (December, January, February and march months) for the last five years. The experiment was conducted in Jericho area within the period of December 2007 until March 2008. The two donums experiment area was divided into five treatments (T1 to T5) according to different E_(t0). Each treatment consists of three replicates distributed randomly. Four of these treatment were controlled by measuring the quantity of water delivered to each one The 5th one (T5) was controlled by the farmer, where he used water as usual Drip irrigation technique was applied. Flow meters were used to measure the deliverable water by each treatment. Cucumber yield by each treatment was weighted in each harvest case. The water use efficiency was calculated and compared the production of treatments with water consumed. The results of this experiment show that treatment T2 where E_(t0)= 80% have the best results in saving water and good yield., and the current water amount consumed by one donum could be reduced (35%) from 450 m 3 to 169 m~3 without negative impact on the yield.