Assessing temporal-spatial variations and classifying water quality of the Dinachal River, Iran, through field data collection

Document Type : Research Paper

Authors

1 Irrigation and Reclamation Engineering Department, Agricultural Faculty, University of Tehran, Karaj, Iran.

2 Professor, Department of Renewable Energies and Sustainable Resources Engineering, Faculty of New Sciences and Technologies, University of Tehran, Tehran, IRAN.

Abstract

Rivers play a crucial role as a primary water source for societies, emphasizing the need for continuous monitoring of their quality. In this article, we focus on the assessment of water quality in Dinachal River, located in Gilan province. The evaluation was conducted through field studies, sampling, and laboratory methods. Specifically, we measured and analyzed five hydraulic parameters and thirteen water quality parameters, including nitrate, phosphate, temperature, and acidity. The study encompassed seven selected sections along a 25 km stretch of Dinachal River in September 2021. To analyze the data, we employed various methods such as Schoeller, Piper, and Wilcox, along with the FAO and WQI indices. Spatially comparing the river water quality revealed a consistent increase in most parameters from the upstream section, with a steeper rise observed from the station near SafarMahaleh village (section4) towards the river's end. Notably, three parameters electrical conductivity, nitrate, and total dissolved solids experienced significant increases. Electrical conductivity rose from 315.67 µS/cm to 712 µS/cm, total dissolved solids increased from 202.03 to 455.68 mg/l, and nitrate levels elevated from 11.27 mg/l to 69.47 mg/l along the river. Conversely, nitrate levels rose from 19.4 mg/l to 21.4 mg/l, and electrical conductivity increased from 328 µS/cm to 416µS/cm. When comparing data between 1996and2016, specifically for the months of July and June, we noted that agricultural drains had caused nitrates to exceed the permissible limit. The findings indicate an overall deterioration in certain parameters, particularly in relation to electrical conductivity, nitrate levels, and total dissolved solids. These results emphasize the need for effective measures to mitigate pollution sources and preserve the river's water quality for the well-being of the surrounding communities.

Keywords

Main Subjects


Assessing temporal-spatial variations and classifying water quality of the Dinachal River, Iran, through field data collection

EXTENDED ABSTRACT

Introduction

The monitoring and assessment of water quality in rivers play a pivotal role in understanding the dynamics of aquatic ecosystems and their interactions with anthropogenic activities. The Dinachal River, located in Gilan Province, serves as a vital water source for both natural habitats and human utilization. Water quality, a key determinant of the river's ecological health and its suitability for various purposes, is subject to complex temporal and spatial variations influenced by a myriad of factors. The aim of the present article is to monitor the temporal and spatial quality of water in the Dinachal River in Gilan Province, based on field studies, sampling, and laboratory experiments.

Materials and Methods

The Dinachal River, coursing through the Gilan Province of Iran, was chosen as the focal point of this study due to its ecological significance and human dependency. The river's diverse catchment area, characterized by a blend of agricultural, residential, and industrial activities, provides a rich context for examining the intricate relationships between land use practices and water quality dynamics. To monitor the water quality of this river, five hydraulic parameters and thirteen water quality parameters such as nitrates, phosphates, temperature, and acidity were measured and studied at seven selected sections along a 25-kilometer stretch of the river. The test results are presented for use by other researchers in this article. For spatial monitoring, the variations in water quality parameters from upstream to downstream were compared, and for temporal monitoring, the data from research conducted in 2012 were compared with the data obtained from field visits. To analyze the results, many diagrams and indices such as Schuler, Piper, Wilcox diagrams, as well as FAO and WQI indices were used.

Results

The results of the spatial comparison of river water quality indicate that the values of most parameters, including phosphorus, sodium, calcium, and potassium, gradually increased from upstream to downstream, with a relatively constant slope, but experienced a sharper increase from section 4 onwards. Among these parameters, electrical conductivity, nitrate, and total dissolved solids have shown significant increases across the examined stretch. Specifically, the electrical conductivity has increased from 315.67 µS/cm to 712 µS/cm, total dissolved solids have increased from 202.03 mg/l to 455.68 mg/l, and nitrate concentration has increased from 11.27 mg/l to 69.47 mg/l. However, the acidity parameter, in contrast to the others, exhibited only a minor change, increasing from 7.75 to 7.82, whereas the dissolved oxygen experienced a reduction from 7.68 mg/l to 4.99 mg/l. Furthermore, the results of the temporal comparison of river water quality demonstrate that the dissolved oxygen content has experienced a negligible decrease of approximately 8%, while nitrate concentration has increased from 19.4 mg/l to 21.4 mg/l, and electrical conductivity has increased from 328 µS/cm to 416 µS/cm, when compared to the past. Notably, the acidity parameter has shown no substantial variation from the past, decreasing from 7.91 to 7.81. Based on comparisons spanning from 1996 to 2016, encompassing the months of June to July, it is evident that due to the inflow of agricultural runoff, nitrate levels have exceeded permissible limits. Nonetheless, when examinations were conducted in September 2021, marked by the absence of agricultural activities, the nitrate conditions along the entire river, except for the final segment, exhibited stability.

Conclusion

 In conclusion, this study underscores the crucial significance of monitoring and comprehending the temporal and spatial dynamics of water quality in the Dinachal River within Gilan Province. The results pinpoint variations in numerous parameters, illuminating the impact of agricultural activities and other factors on water quality. These findings underscore the necessity of sustainable resource management strategies to maintain the health and usability of surface water resources in the region.

Alipour, A., Rahimi, J & Azarnivand, A. (2016). Groundwater Quality Analysis for Drinking and Agriculture Purposes- a prerequisite for land use plannig in the arid and semi-arid Regions of Iran. Pasture and watershed scientific-research journal, (2) 70. (In Persian)
Alizadeh, M., Mirzaei & Kiya, H. (2016). Investigating the Spatial Trends of Water Quality Indicators In the Kan and Karaj River Basins. Journal of Environmental Health Engineering, (3)4. (In Persian)
Bahrami, N & Asadi, I. (2014). Groundwater: Qualitative Assessment of Groundwater Resources of Shabestar-Sufian Plain. National Congress of Irrigation and Drainage of Iran. (In Persian)
Bhatti, E. U. H., Khan, M. M., Shah, S. A. R., Raza, S. S., Shoaib, M., & Adnan, M. (2019). Dynamics of water quality: Impact assessment process for water resource management. Processes, 7(2), 102
Chen, S. S., Kimirei, I. A., Yu, C., Shen, Q., & Gao, Q. (2022). Assessment of urban river water pollution with urbanization in East Africa. Environmental science and pollution research international, 29(27), 40812–40825.
De Baat, M. L., Van der Oost, R., Van der Lee, G. H., Wieringa, N., Hamers, T., Verdonschot, P. F. M., De Voogt, P., & Kraak, M. H. S. (2020). Advancements in effect-based surface water quality assessment. Water research, 183, 116017.
FAO, (1970). FAO standards for irrigation.
Hoaghia, M. A., Moldovan, A., Kovacs, E., Mirea, I. C., Kenesz, M., Brad, T & Moldovan, O. T. (2021). Water quality and hydrogeochemical characteristics of some karst water sources in Apuseni Mountains, Romania. Water13(6), 857.
Maghsoudi, R., Abedi Koupai, J & Mir Abbasi Najafabadi, R. (2021). Investigating the effects of Beheshtabad river water Abstraction on Downstream Water Quality. Iran Water and Soil Research, (9) 52. (In Persian)
Manafi Mollayousefi, M & Malekani, L (2022). Evaluation of the Water Quality of Sofi-chai River by Shannon Entropy and AHP methods. Scientific Research Journal of Irrigation and Water Engineering of Iran, (2) 13. (In Persian)
Megahed, H. A., GabAllah, H. M., Ramadan, R. H., AbdelRahman, M. A., D’Antonio, P., Scopa, A., & Darwish, M. H. (2023). Groundwater Quality Assessment Using Multi-Criteria GIS Modeling in Drylands: A Case Study at El-Farafra Oasis, Egyptian Western Desert. Water, 15(7), 1376.
Mohammadi Ghaleni, M & Ebrahimi, K. (2019). Sensitivity analysis of the Qual2kw Model in the Modeling of water Quality parameters of Sefirod. Iran Irrigation and Drainage Journal, (5) 13. (In Persian)
Mohammadi Ghaleni, M & Kardan Moghaddam, H. (2022). Introducing a New Drinking Quality Index for Surface Water Resources Using Multivariate Analysis (Case Study: Sefidroud River). Water and soil research, (4)36. (In Persian)
Mohammadi Ghaleni, M., Ebrahimi, K & Omid, MH. (2014). Investigating the self-purification of Pisikhan and Dinachal Rivers from Gilan Province with the Development and Application of Mathematical Model and Field Data Collection. Applied Research Plan. Gilan Regional Water Joint Stock Company, (2) 14. (In Persian)
Naderi, MH., Pourgholam Amiji, M., Khoshravesh, M., Ghojoghi, A & Arab, N. (2019). Evaluation of spatial-temporal Comparisons of Water Quality Parameters and Health of Ziarat River Using NSFWQI Quality Index and Statistical Analysis. Iran Water and Soil Research (Agricultural Sciences of Iran), (6) 51. (In Persian)
Neil R. McIntyre, Thorsten Wagener, Howard S. Wheater, Zeng Si Yu (2003); Uncertainty and risk in water quality modelling and management. Journal of Hydroinformatics. 5 (4): 259–274.
Noori, R., Jafari, F; Forman Asgharzadeh, D & Akbarzadeh, A. (2011). Offering a Proper Framework to Investigate Water Quality of the Atrak river. Health and environment, (2)4. (In Persian)
Ouyang, Y. (2005). Evaluation of river water quality monitoring stations by principal component analysis. Water Research, 39(12), 2621-2635.
Pashazadeh Laleh, Z., Jafari, H & Vaezi Hir, AR. (2019). Assessment of Aji-chai River Pollution in Tabriz Plain Area Using Water Quality Indices. Water and soil, (6)34. (In Persian)
Rahimi, M., Besharat, S & Verdinejad, V (2015). Quality Evaluation of the of Groundwater Resources of Ardabil Aquifer for Agricultural and Drinking Uses. Environment and water engineering, (4)2. (In Persian)
Rahnama, S & Sayari, N. (2018). Survey and Trends of Chemical Water Quality Parameters of Tajan River Water Quality Using Principal Component Analysis and AquaChem Software. Human and Environment Quarterly, (48)1. (In Persian)
Ramalho, F. L., Cabral, J. B. P., Alves, W. D. S., de Barcelos, A. A., dos Santos, F. F., & Paulino, A. T. (2022). Spatial and temporal evaluation of water streams using quality indexes: a case study. Water14(21), 3526.
Ravikumar, P., Somashekar, R. K., & Prakash, K. L. (2015). A comparative study on usage of Durov and Piper diagrams to interpret hydrochemical processes in groundwater from SRLIS river basin, Karnataka, India. Elixir Earth Sci80(2015), 31073-31077.
Salehi, H., Soleymani, L & Ebrahimi Mohammadi, Sh (2015). An Assesment of Groundwater Quality Using the AqQA Model and Determination of the Most Suitable Method for Their Zoning (case study: Qorve city, Kurdistan). Scientific Quarterly Journal of Water Resources Engineering, (29)9. (In Persian)
Sarkar, A., & Pandey, P. (2015). River water quality modelling using artificial neural network technique. Aquatic procedia, 4, 1070-1077.
Schoeller, H. (1956). Géochimie des eaux souterraines. Societe Technip.‏
Shahinejad, B., Izadi, Z. & Javadi, B. (2021). Evaluation of Qual2Kw Model in Qualitative Simulation of Khorram Abad River. Hydrogeomorphology, (26)8. (In Persian)
Whitehead, P., Dolk, M., Peters, R., & Leckie, H. (2019). Water Quality Modelling, Monitoring, and Management. Water Science, Policy, and Management. 55-73.
Zait, R.; Sluser, B.; Fighir, D.; Plavan, O.; Teodosiu, C. (2022) Priority Pollutants Monitoring and Water Quality Assessment in the Siret River Basin, Romania. Water14, 129.