Document Type : Original Articles

Authors

1 Department of Environmental Health Engineering, School of Health and Nutrition, Shiraz University of Medical Sciences, Shiraz, Iran

2 Department of Civil Engineering, college of engineering, Shiraz University, Shiraz, IR Iran

3 Department of Epidemiology, School of Health, Shiraz University of Medical Sciences, Shiraz, IR Iran

4 Department of Environmental Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, IR Iran

Abstract

Background: Groundwater nitrate pollution is an important environmental problem in water resources management. In this regard, specific measures aiming at prevention of water pollution will be helpful to managers and decision-makers. Identification of aquifers’ vulnerable areas and determination of groundwater protection zones using most widely used models, such as DRASTIC and CD, are one of the most useful approaches in water resources’ hygiene. Objective: The present study aimed to assess the vulnerability of Shiraz plain’s unconfined aquifer using the above-mentioned models. Methods: The main hydro-geologic factors affecting the transmission of pollution, including depth to water table, net recharge, aquifer media, soil media, topography, impact of the vadose zone, aquifer hydraulic conductivity, and land use parameters were rated, weighted, and integrated using GIS 9.3. Finally, the maps of Shiraz plain’s unconfined aquifer vulnerability were prepared. Results: The vulnerability maps based on these two indexes showed very similar results, identifying the southeastern part of the aquifer, around Maharlu Lake, as the vulnerable zone. The observed nitrate concentrations from the wells in the underlying aquifer were in accordance with these findings. The results of sensitivity analyses indicated the depth parameter as the most effective parameter in vulnerability assessment of Shiraz plain. Conclusion: As Shiraz plain has been covered with fine-grained sediments, except for some central and south-east regions which have moderate vulnerability and high nitrate concentration, its vulnerability is low. Given the intensive agricultural activities and also the rise in groundwater level in southeastern regions, more attention should be paid to these areas.

Keywords

  1. Kumar SK, Rammohan V, Sahayam JD, Jeevanandam
  2. M. Assessment of ground water quality and
  3. hydrogeochemistry of Manimuktha River basin, Tamil
  4. Nadu, India. Environ Monit Assess 2009; 159(1-4):
  5. -51.
  6. Fazeli M, Kalantari N, Rahimi MH, Khoobyari A.
  7. Temporal and spatial distribution of nitrate in the Zydun
  8. plain,s groundwater resources. Water Eng 2011; 4(8):
  9. -51.
  10. Tilahun K, Merkel BJ. Assessment of groundwater
  11. vulnerability to pollution in Dire Dawa, Ethiopia using
  12. DRASTIC. Environ. Earth Sci 2010; 59(7): 1485-96.
  13. Sinan M, Razack M. An extension to the DRASTIC
  14. model to assess groundwater vulnerability to pollution:
  15. application to the Haouz aquifer of Marrakech
  16. (Morocco). Environ Geol 2009; 57(2): 349-63.
  17. Hailin Y, Ligang X, Chang Y, Jiaxing X. evaluation of
  18. groundwater vulnerability with improved DRASTIC
  19. method. Procedia Environ. Sci 2011; 10: 2690-5.
  20. Rahman A. A GIS based DRASTIC model for assessing
  21. groundwater vulnerability in shallow aquifer in
  22. Aligarh, India. Appl. Geogr 2008; 28(1): 32-53.
  23. Leone A, Ripa M.N, Uricchio V, Deak J, Vargay
  24. Z. Vulnerability and risk evaluation of agricultural
  25. nitrogen pollution for Hungary’s main aquifer using
  26. DRASTIC and GLEAMS models. J Environ Manage
  27. ; 90(10): 2969-78.
  28. Nel J, Xu Y, Batelaan O, Brendonck L. Benefit and
  29. implementation of groundwater protection zoning
  30. in South Africa. Water Resour Manage 2009; 23:
  31. -911.
  32. Saidi S, Bouri S, Ben Dhia H. Groundwater vulnerability
  33. and risk mapping of the Hajeb-jelma aquifer (Central
  34. Tunisia) using a GIS-based DRASTIC model. Environ
  35. Earth Sci 2010; 59: 1579-88.
  36. Qian H, Li P, Howard K.W.F, Yang C, Zhang X.Assessment of groundwater vulnerability in the
  37. Yinchuan Plain, Northwest China using OREADIC.
  38. Environ Monit Assess 2012; 184: 3613-28.
  39. Babiker IS, Mohamed MAA, Hiyama T, Kato K. A
  40. GIS-based DRASTIC model for assessing aquifer
  41. vulnerability in Kakamigahara Heights, Gifu
  42. Prefecture, central Japan. Sci. Total Environ 2005;
  43. (1): 127-40.
  44. Martinez-Bastida JJ, Arauzo M, Valladolid M. Intrinsic
  45. and specific vulnerability of groundwater in central
  46. Spain: the risk of nitrate pollution. Hydrogeol J 2010;
  47. (3): 681-98.
  48. Sener E, Sener S, Davraz A. Assessment of aquifer
  49. vulnerability based on GIS and DRASTIC methods:
  50. a case study of the Senirkent-Uluborlu Basin (Isparta,
  51. Turkey). Hydrogeol J 2009; 17(8): 2023-35.
  52. Pathak DR, Hiratsuka A, Awata I, Chen L. Groundwater
  53. vulnerability assessment in shallow aquifer of
  54. Kathmandu Valley using GIS-based DRASTIC model.
  55. Environ Geol 2009; 57(7): 1569-78.
  56. Al Hallaq AH, Elaish BSA. Assessment of aquifer
  57. vulnerability to contamination in Khanyounis
  58. Governorate, Gaza Strip-Palestine, using the DRASTIC
  59. model within GIS environment. Arab. J Geosci 2012;
  60. (4): 833-47.
  61. Wen X, Wu J, Si J. A GIS-based DRASTIC model for
  62. assessing shallow groundwater vulnerability in the
  63. Zhangye Basin, northwestern China. Environ Geol
  64. ; 57(6): 1435-42.
  65. Lee S. Evaluation of waste disposal site using the
  66. DRASTIC system in Southern Korea. Environ Geol
  67. ; 44(6): 654-64.
  68. Jamrah A, Al-Futaisi A, Rajmohan N, Al-Yaroubi S.
  69. Assessment of groundwater vulnerability in the coastal
  70. region of Oman using DRASTIC index method in GIS
  71. environment. Environ Monit Assess. 2008; 147(1-3):
  72. -38.
  73. Al-Adamat RAN, Foster IDL, Baban SMG.
  74. Groundwater vulnerability and risk mapping for the
  75. Basaltic aquifer of the Azraq basin of Jordan using
  76. GIS, Remote sensing and DRASTIC. Appl Geogr 2003;
  77. : 303-24.
  78. Chitsazan M, Akhtari Y. A GIS-based DRASTIC
  79. Model for Assessing Aquifer Vulnerability in Kherran
  80. Plain, Khuzestan, Iran. Water Resour Manage 2009;
  81. : 1137-55.
  82. Barber C, Bates LE, Barron R, Allison H. Assessment
  83. of the relative vulnerability of groundwater to pollution:
  84. a review and background paper for the conference
  85. workshop on vulnerability assessment. J Aust Geol
  86. Geophys 1993; 14(2/3): 1147-54.
  87. Merchant JW. GIS-based groundwater pollution hazard
  88. assessment: a critical review of the DRASTIC model.
  89. ISPRS J Photogramm 1994; 60(9): 1117-28.
  90. Napolitano P, Fabbri A. Single-parameter sensitivity
  91. analysis for aquifer vulnerability assessment using
  92. DRASTIC and SINTACS. Proceedings of the Vienna
  93. Conference on HydroGIS 96: Application of geographic
  94. information systems in hydrology and water resources
  95. management IAHS Publ 1996; 235: 559-66.
  96. Brahim FB, Khanfir H, Bouri S. Groundwater
  97. vulnerability and risk mapping of the Northern Sfax
  98. Aquifer, Tunisia. Arab J Sci Eng 2012; 37(5): 1405-21.
  99. Zhou Sh, Wu Y, Wang Zh, Lu L, Wang R. The nitrate
  100. leached below maize root zone is available for deeprooted
  101. wheat in winter wheat-summer maize rotation
  102. in the North China Plain. Environ Pollut 2008; 152: