Extended Abstract
Introduction
In recent years, hydrological systems have been increasingly affected by recurrent droughts and global climate change. Consequently, groundwater resources have gained growing significance. Groundwater has consistently attracted attention due to its inherent characteristics, including stability against seasonal fluctuations, reliability of extraction during drought conditions, relatively lower vulnerability, and superior quality compared to surface water. Karst springs, as natural outlets of aquifers, are considered fundamental components of urban hydrological systems. These resources play a pivotal role in supplying drinking water, maintaining ecological sustainability, and ensuring the social well-being of cities. Khorramabad, a city in western Iran, benefits from a dense network of springs and consequently supplies a significant portion of the region's water demand through its groundwater resources. Nevertheless, rapid urban expansion, land-use changes, excessive anthropogenic extraction, and climatic fluctuations have posed serious challenges to the quantitative and qualitative sustainability of these valuable resources. In response, the present study was conducted with the aim of an integrated analysis of the hydrological and economic status of five representative springs in Khorramabad, namely Motahari, Qiu, Golestan, Gardab-e Sangi, and Gardab-e Daraii. The findings of this research can provide a scientific basis for sustainable management, conservation prioritization, and economic policy-making concerning urban water resources.
Materials and Methods
The present study was conducted using an integrated (hydrological and economic) approach on five principal springs of Khorramabad city over the statistical period from 1984 to 2024. In the quantitative hydrology section, monthly discharge data and the non-parametric Mann–Kendall test were employed using Microsoft Excel to identify long-term trends. The hydrological and meteorological drought status was assessed using the SPI, SPEI, RDI, and SDI indices at temporal scales of 1, 3, 6, 12, and 24 months, utilizing the Python programming environment. In the water quality section, the Water Quality Index (WQI) was calculated in Excel, and Schoeller and Piper diagrams were generated using Chemistry software. The main parameters evaluated in the water quality assessment of the Khorramabad springs included pH, total hardness (TH), electrical conductivity (EC), total dissolved solids (TDS), chloride (Cl⁻), sulfate (SO₄²⁻), nitrate (NO₃⁻), phosphate (PO₄³⁻), bicarbonate (HCO₃⁻), sodium (Na⁺), potassium (K⁺), calcium (Ca²⁺), and magnesium (Mg²⁺). For economic valuation, the Contingent Valuation Method (CVM) was employed. The required data were collected through questionnaires and in-person interviews with 100 citizens residing in Khorramabad. Statistical analysis of the questionnaire data was performed using SPSS and Excel software. Finally, the Logit model and the maximum likelihood estimation method were applied in EViews13 software to estimate the Willingness to Pay (WTP) and the model parameters.
Results and Discussion
The findings of this study generally indicate that the spring water resources of Khorramabad are, on the one hand, facing a gradual and significant decline in discharge, while on the other hand, they possess favorable chemical quality. Long-term trend analysis of discharge reveals that the discharge of the springs has exhibited a significant decreasing trend over the past four decades. This gradual decline can be attributed to the cumulative effects of climate change, reduced aquifer recharge, and the high sensitivity of karst systems to environmental stresses. The examination of hydrological droughts also revealed that the springs have experienced severe flow reduction during sustained drought periods. From an economic perspective, the contingent valuation results showed that a significant proportion of citizens make direct use of spring water, with drinking water consumption being the predominant use of these resources. The willingness to pay for non-use values (e.g., preserving ecological and tourism values) was estimated at approximately 85,000 Iranian tomans per m3. Overall, there is a significant correlation between the hydrological status and the economic value of the springs; springs with greater flow stability and higher quality (e.g., Qiu and Motahari) also possess higher economic value, and people exhibit a greater willingness to pay for their protection. Moreover, the true value of the services provided by these resources far exceeds the current operational costs, and neglecting these values can lead to suboptimal decision-making and the perpetuation of unsustainable trends.
Conclusion
This study emphasizes that the sustainable management of Khorramabad's springs cannot rely solely on either hydrological or economic approaches alone; rather, it requires an integrated and holistic approach encompassing continuous scientific monitoring, hydrological analysis, economic policy-making based on the true value of resources, and active social participation. The findings can serve as a scientific basis for conservation prioritization (especially for springs with lower flow stability, such as Gardab-e Sangi), revising water allocation and pricing policies based on true economic value, and strengthening decision-making systems in urban water resource management. Ultimately, enhancing public awareness, investing in environmental education, and establishing mechanisms for public financial participation are fundamental prerequisites for the sustainable preservation of these valuable resources against climatic and anthropogenic threats. Based on the research findings, a comprehensive and integrated approach is proposed for the sustainable management of Khorramabad's springs. This approach should include: (1) continuous hydrological and water quality monitoring; (2) protection of karst recharge zones; (3) environmental education and public awareness programs to enhance social participation, particularly among youth and direct users; (4) integration of economic valuation (using contingent valuation and ecosystem service assessment) into water policy-making; (5) adaptive management to climate change, considering cumulative effects of medium- and long-term droughts; and (6) strengthening inter-sectoral collaboration among relevant organizations. |
