Groundwater of Abu Dhabi Emirate: a regional assessment by means of remote sensing and geographic information system
- PDF / 14,478,043 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 11 Downloads / 190 Views
ORIGINAL PAPER
Groundwater of Abu Dhabi Emirate: a regional assessment by means of remote sensing and geographic information system Samy Ismail Elmahdy 1 & Mohamed Mostafa Mohamed 1,2
Received: 15 January 2015 / Accepted: 13 April 2015 # Saudi Society for Geosciences 2015
Abstract Mapping of geological, topographical, and hydrological elements is critical for understanding and assessing the regional hydrological setting in an arid region. In this study, a synergistic approach has been developed, which uses a combination of remote sensing data and geographic information system (GIS) to map factors controlling groundwater recharge, discharge, and quality across the Abu Dhabi Emirate. The Spectral Angel Mapper (SAM) algorithm, which uses a n-D angle to match the pixels to reference spectra, was used to map new water-bearing rocks, and the deterministic eight-node (D8) algorithm, which allows flow to only one of the eight neighbors based on the direction of steepest descent, was used to map paleochannels. The terrain category was applied to simulate seawater intrusion from digital elevation model (DEM). New maps of lithology, normalized difference vegetation index (NDVI), and paleochannels were derived and interpreted from multi-sources of remote sensing data. The study indicated that the area was produced by a fluvial and eolian process and recharged by local, intermediate, and regional flows. The results showed that the Oman and Hafeet Mountains are the natural sources of groundwater recharge as well as HCO3, Ca, Na, and Mg in groundwater. The mapped factors were spatially correlated with hydrologic anomalies observed in groundwater wells. The integrated approach is
* Samy Ismail Elmahdy [email protected] 1
Civil and Environmental Engineering Department, United Arab Emirates University, P.O. Box 15551, Al-Ain, United Arab Emirates
2
Irrigation and Hydraulics Department, Faculty of Engineering, Cairo University, P.O. Box 12211, Giza, Egypt
timely, cost-effective, and can be used in arid regions for numerical modeling as well as water balance analysis. Keywords Remote sensing . GIS . UAE . Groundwater . Paleochannels . Al Ain
Introduction The availability of surface water in the United Arab Emirates (UAE) is limited because of low rainfall and high evaporation rates. Additionally, the UAE has been experiencing rapid urbanization and intensive human activities. These activities have a negative impact on groundwater quality in the Quaternary sand aquifer underlying the city. Mapping of hydrological, environmental, and geological elements is a key component to understand the hydrological setting of Abu Dhabi Emirate. In Abu Dhabi Emirate, natural elements such as paleochannels, lithological units, topographic slope, and anthropological factors affect agricultural activity, aquifer thickness, shallow water table, and seawater intrusion resulting in increased groundwater salinity and contamination (Mohamed and Elmahdy 2014; Elmahdy and Mohamed 2014a, c). Groundwater assessment in Abu Dhabi Emirate provides the hydrol
Data Loading...
