Skip to main content
Log in

Application of data-driven methods to predict the sodium adsorption rate (SAR) in different climates in Iran

  • Original Paper
  • Published:
Arabian Journal of Geosciences Aims and scope Submit manuscript

Abstract

Water quality is a very important factor for drinking, irrigation, and industry usage. Sodium adsorption rate (SAR) is one of the water quality parameters, which has a vital role in irrigation because of decreasing infiltration in the soil. For future planning of irrigation, forecasting of SAR is necessary. We applied radial basis function (RBF), adaptive neuro-fuzzy inference system-grid partitioning (ANFIS-GP), ANIFIS-SC (SC is subtractive clustering), and ANFIS-FCMC (FCMC is fuzzy c-means clustering), to predict SAR of Aras, Sefid-Rud, Karun, and Mond Rivers, which cover part of the north, northwest, southwest, and south of Iran. We used 15 years’ monthly data, including discharge, pH, chloride (Cl), sulfate (SO4), bicarbonate (HCO3), and electrical conductivity (EC), as input to neural networks. The RBF neural network reached proper results of SAR prediction in training and testing in the Aras, Sefid-Rud, Karun, and Mond Rivers, in which the mean square error (MSE) for training was between 0.000255 and 0.0017 and coefficient of determination (R2) of testing varies between 0.902 and 0.96 using normalized data. ANFIS-GP did not reach the proper model performance (R2 were between 0–0.21 and 0.55 and index of agreement were between 0.55 and 0.88) for the four rivers in comparison with ANFIS-SC and ANFIS-FCMC, since ANFIS-GP may need a long time of processing to analyze numerous combinations of the membership function. The normalization of input data of ANFIS-FCMC improved the performance of the model of the four rivers slightly. However, the normalization of input data of ANFIS-FCMC for SAR prediction of the Aras River did not improve the performance of the model (R2 = 0.48 and index of agreement = 0.44). We could state that variable processing via normalization might not necessarily improve ANFIS model performance. The training of ANFIS did not reach appropriate results for the Mond River because of scattering data. We may state that ANFIS is not a proper method for using scatter data. The results of sensitivity in Sefid-Rud River use the RBF neural network indicated that the electrical conductivity had a maximum effect (19.8%) and the discharge (13%) had the minimum effect on SAR prediction.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14

Similar content being viewed by others

References

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Gholamreza Asadollahfardi.

Additional information

Responsible Editor: Broder J. Merkel

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Rahnama, E., Bazrafshan, O. & Asadollahfardi, G. Application of data-driven methods to predict the sodium adsorption rate (SAR) in different climates in Iran. Arab J Geosci 13, 1160 (2020). https://doi.org/10.1007/s12517-020-06146-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s12517-020-06146-4

Keywords

Navigation