Extended Abstract

1. Introduction

Water scarcity has become one of the most critical challenges threatening the sustainability of agricultural production worldwide, particularly in arid and semi-arid regions. Agriculture accounts for nearly 70% of global freshwater withdrawals, making the efficient use of water resources a fundamental prerequisite for ensuring long-term food security and environmental sustainability. In Iran, recurrent droughts, excessive groundwater abstraction, declining aquifer levels, and the impacts of climate change have considerably intensified pressure on agricultural water resources. Consequently, improving water productivity while simultaneously reducing environmental degradation has become an essential objective for sustainable agricultural development. Among field crops, potato (Solanum tuberosum L.) plays a strategic role in food security due to its high yield potential, considerable economic value, and nutritional importance. Nevertheless, potato production is characterized by relatively high irrigation water requirements and intensive fertilizer application, which may increase both water consumption and environmental pollution. Therefore, evaluating potato production solely from an economic perspective is insufficient. A comprehensive sustainability assessment should simultaneously consider economic efficiency and environmental impacts associated with water use. The Water Footprint (WF) framework has emerged as one of the most comprehensive tools for evaluating agricultural water use by distinguishing blue, green, and grey water components. Combined with water productivity and sustainability indices, this approach provides valuable insights into the balance between agricultural profitability and environmental conservation.

Dehgolan Plain, located in Kurdistan Province, western Iran, is one of the country's major potato-producing regions. However, intensive groundwater exploitation and continuous agricultural expansion have placed considerable pressure on local water resources. Despite the importance of this production area, comprehensive studies simultaneously investigating economic water productivity and environmental sustainability remain limited. Accordingly, this study aimed to evaluate the sustainability of potato production in Dehgolan Plain during the period 2011–2021 (Iranian calendar: 1390–1400) using integrated indicators of economic water productivity and environmental sustainability.



2. Materials and Methods

This study used a quantitative analytical approach based on annual agricultural and climatic data for potato production in the Dehgolan Plain during 2011–2021. Data on cultivated area, yield, production costs, and net profit were obtained from the Kurdistan Agricultural Jihad Organization, while climatic data required for estimating crop water requirements were obtained from meteorological sources. Economic variables were converted to constant 2021 prices to eliminate the effect of inflation. Water Footprint (WF) was estimated using the methodology proposed by Hoekstra et al. (2011) and included Blue WF, Green WF, and Grey WF. Grey WF was estimated based on nitrogen fertilizer use. Water Economic Productivity (WEP), Economic Sustainability Index (ESI), Water Environmental Stress Index (WESI), and Composite Sustainability Index (CPS) were subsequently calculated to evaluate the economic and environmental performance of the production system. Descriptive analyses and a paired-samples t-test were used to examine temporal variations and compare the Blue and Grey WF components.





3. Results and Discussion

The results showed that the mean potato yield and Total Water Footprint were 33.4 t ha⁻¹ and 443 m³ t⁻¹, respectively. Blue and Grey WF were the dominant components, with mean values of 228 and 212 m³ t⁻¹, respectively, accounting for approximately 51% and 47% of the total WF. Green WF had a limited contribution, averaging about 1.5% of total WF, which indicates the substantial role of irrigation in potato production. Although the descriptive mean of Blue WF was higher than that of Grey WF, the paired-samples t-test showed that their difference was not statistically significant (t(10)=1.008, p=0.337). Grey WF fluctuated considerably during the study period, reaching its maximum value of 292 m³ t⁻¹ in 2018, which was associated with higher nitrogen fertilizer use and lower crop yield.

From the economic perspective, mean net profit was 163 million Toman ha⁻¹, while WEP averaged 148 Toman m⁻³ and varied from 99 to 182 Toman m⁻³. The ESI ranged from 68 to 135, with a mean of 101, indicating substantial annual variation in economic sustainability relative to the study-period average. The highest WEP and ESI were recorded in 2017, whereas the lowest WEP occurred in 2021. The CPS averaged 328 Toman m⁻³ and ranged from 218 to 438 Toman m⁻³. Environmental pressure also fluctuated over time, with the highest WESI recorded in 2020. Overall, the results indicate that economic profitability alone does not necessarily ensure sustainability and that improvements in water-use efficiency should be accompanied by appropriate management of nitrogen inputs and environmental pressure.





4. Conclusion

The findings demonstrate that potato production in the Dehgolan Plain is substantially dependent on irrigation water and is associated with considerable potential environmental pressure from nitrogen fertilizer use. The results further indicate that sustainable production cannot be assessed solely on the basis of economic profitability, as favorable economic performance does not necessarily coincide with lower environmental pressure. An integrated assessment of water footprint, economic water productivity, and sustainability indicators therefore provides a more comprehensive basis for evaluating production sustainability. Accordingly, improving irrigation efficiency and scheduling, optimizing nitrogen fertilizer application based on crop requirements, and enhancing water economic productivity are essential strategies for maintaining potato profitability while reducing pressure on regional water resources.