Modeling groundwater vulnerability to pollution using Optimized DRASTIC model

7th IGRSM International Remote Sensing & GIS Conference and Exhibition

地球科学;计算机科学

Mogaji, Kehinde Anthony^1,2 ; Lim, Hwee San^2 ; Abdullar, Khiruddin^2

Department of Applied Geophysics, Federal University of Technology, P.M.B. 704, Akure, Nigeria^1

School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia^2

关键词: Analytic hierarchy process (ahp);    Correlation factors;    Decision support models;    Environmental decision making;    Groundwater vulnerability;    Groundwater vulnerability assessments;    Spatial Decision Support;    Vulnerability index;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/20/1/012002/pdf
DOI  :  10.1088/1755-1315/20/1/012002

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

The prediction accuracy of the conventional DRASTIC model (CDM) algorithm for groundwater vulnerability assessment is severely limited by the inherent subjectivity and uncertainty in the integration of data obtained from various sources. This study attempts to overcome these problems by exploring the potential of the analytic hierarchy process (AHP) technique as a decision support model to optimize the CDM algorithm. The AHP technique was utilized to compute the normalized weights for the seven parameters of the CDM to generate an optimized DRASTIC model (ODM) algorithm. The DRASTIC parameters integrated with the ODM algorithm predicted which among the study areas is more likely to become contaminated as a result of activities at or near the land surface potential. Five vulnerability zones, namely: no vulnerable(NV), very low vulnerable (VLV), low vulnerable (LV), moderate vulnerable (MV) and high vulnerable (HV) were identified based on the vulnerability index values estimated with the ODM algorithm. Results show that more than 50% of the area belongs to both moderate and high vulnerable zones on the account of the spatial analysis of the produced ODM-based groundwater vulnerability prediction map (GVPM).The prediction accuracy of the ODM-based-GVPM with the groundwater pH and manganese (Mn) concentrations established correlation factors (CRs) result of 90 % and 86 % compared to the CRs result of 62 % and 50 % obtained for the validation accuracy of the CDM-based GVPM. The comparative results, indicated that the ODM-based produced GVPM is more reliable than the CDM-based produced GVPM in the study area. The study established the efficacy of AHP as a spatial decision support technique in enhancing environmental decision making with particular reference to future groundwater vulnerability assessment.