Management strategies of a critical aquifer under the climate change in Jahrum of South-Central Iran (original) (raw)

The Jahrum aquifer is situated in South-Central Iran, within an arid climate. The water table and minimum hydraulic storage (MHS) of Jahrum aquifer have been significantly reduced in recent decades due to groundwater over-exploitation. The MHS is defined as "volume of water in excess of recycle water, stored in most aquifers to provide enough pressure-head to push water toward the discharging zones". The daily precipitation and temperature of Canadian's Coupled Global Climate Model 3.1 is downscaled at the Jahrum climatic station using LARS-WG for the 2015-2095 period and scenarios B1, A1B and A2. Under three scenarios, the precipitation will decrease and temperature will increase. The annual water balance of the Jahrum aquifer is calculated for the baseline period (1998-2010), as well as for several management alternatives, including reducing cultivated area, or and applying water stress or no stress during the dry periods under the three scenarios. The cultivated area or exploitation, and consequently, total irrigation water requirement is reduced in a way to compensate 50 and 100% volume of the MHS. The MHS recovery depends on the percentage of cultivated area reduction and water stress. In all scenarios and alternatives, the current cultivated area should be reduced, depending on the case, within a range of 61-84% to recover the MHS, completely. The MHS recovery period varies from 45 to 75 years in the three scenarios. It is recommended that the MHS recovery method be used for any aquifer exposed to over-exploitation and climate change.