Assessment of groundwater quality in Seydan-Farooq plain for irrigation and drinking purposes
Message:
Abstract:
Introduction

Groundwater quality study is one of the important tools for the sustainable development of a region and pro vides crucial information for managing water in different sectors. In recent years, water withdrawal from Iran’s aquifers has reduced the groundwater quality in most of the plains. This research was conducted to investigate the groundwater quality of Seydan-Farooq plain for agricultural and drinking purposes and also mapping some effective chemical parameters in these two sections.

Material and methods

In this research, the results of chemical analysis of twelve wells in 2016 were used. First, ground water type and hydrogeochemical facies were determined. Factors controlling groundwater chemistry were determined using Gibbs diagram and plot of Ca+Mg versus SO4+HCO3. To classify water for irrigation, electrical conductivity )EC(, sodium adsorption ratio )SAR(, sodium percentage )%Na(, magnesium ratio, corrosivity ratio, and permeability index were used. Then, the map of some important parameters for irrigation water was prepared. To classify water for drinking pur poses, chemical parameters were first compared with World Health Organization )WHO) guidelines. Next, some important parameters for drinking such as total dissolved solids, total hardness, and chloride ion concentration were compared with existing standards and their effects on human health were discussed. Then, the map of these parameters for the study plain was prepared. Finally, the quality of water for drinking purposes was evaluated using the Schoeller diagram.

Results and discussion

The distribution pattern of samples in Durov diagram indicated the tendency of some samples to reach the end of the hydrogeochemical evolutionary cycle. As such, the bicarbonate type was changed into chloride type in
a short time. Based on Gibbs diagram and the plot of Ca+Mg versus SO4+HCO3, rockwater interaction and dissolution of carbonate rocks were the main factors changing the groundwater chemical quality of the plain. According to SAR value, all samples fell in the excellent category which is suitable for irrigation and there is no risk of soil alkalinity. While in terms of salinity )EC(, they are acceptable in the agricultural sector. Based on the percentage of sodium, samples were categorized as excellent, which are suitable for irrigation. According to the permeability index, all samples, except for one sample, showed good irrigation quality and did not change the soil permeability. In the majority of samples, the magnesium ratio was less than 50, which is suitable for irrigation. Comparison of chemical parameters with the WHO guidelines showed that none of the parameters exceeded the permissible limit. Comparison of TDS and chloride in samples with other existing standards showed that only one sample was brackish, which is not suitable for drinking purposes. Based on the groundwater hardness, water of the study plain was classified as high hardness water. According to the Schoeller diagram, the water quality of the study plain was classified in the good category.

Conclusion

According to the hydrogeochemical results, waterrock interaction and weathering of carbonate minerals are the main factors in changing water chemistry. Since the majority of rocks recharging the aquifer are calcareous, it seems obvious that calcium and bicarbonate ions are dominant in the groundwater. In all samples, except those wells with pos sible saltwater intrusion, parameters such as salinity risk, SAR, sodium solution, and permeability index were acceptable for irrigation and there was no risk of soil alkalinity. Aquifer recharge by limestone-dolomite and dolomitic rocks in some regions has increased the magnesium ratio of groundwater in about 40% of samples. It has also increased the groundwater hardness. None of the chemical parameters exceeded the permissible limit set by the WHO and Schoeller diagram indicated that the water quality of the study plain was classified in the good category.

Article Type:
Research/Original Article
Language:
Persian
Published:
Environmental Sciences, Volume:17 Issue: 3, 2019
Pages:
89 - 106
magiran.com/p2056561  
برخی از خدمات از جمله دانلود متن مقالات تنها به مشترکان مگیران ارایه می‌گردد. شما می‌توانید به یکی از روش‌های زیر مشترک شوید:
اشتراک شخصی
در سایت عضو شوید و هزینه اشتراک یک‌ساله سایت به مبلغ 300,000ريال را پرداخت کنید. همزمان با برقراری دوره اشتراک بسته دانلود 100 مطلب نیز برای شما فعال خواهد شد!
اشتراک سازمانی
به کتابخانه دانشگاه یا محل کار خود پیشنهاد کنید تا اشتراک سازمانی این پایگاه را برای دسترسی همه کاربران به متن مطالب خریداری نمایند!
توجه!
  • دسترسی به متن مقالات این پایگاه در قالب ارایه خدمات کتابخانه دیجیتال و با دریافت حق عضویت صورت می‌گیرد و مگیران بهایی برای هر مقاله تعیین نکرده و وجهی بابت آن دریافت نمی‌کند.
  • حق عضویت دریافتی صرف حمایت از نشریات عضو و نگهداری، تکمیل و توسعه مگیران می‌شود.
  • پرداخت حق اشتراک و دانلود مقالات اجازه بازنشر آن در سایر رسانه‌های چاپی و دیجیتال را به کاربر نمی‌دهد.