Extended Abstract
Introduction
Drought disrupts livelihood and ecological systems in peri-urban areas, triggering widespread population displacement. This displacement leaves profound social consequences on the structure of both origin and destination communities, including the disintegration of social networks, exacerbated inequalities, and altered patterns of urban settlement.
Iran, with an average annual rainfall of 260 mm (one-third of the global average), is among the world's arid countries and has limited water resources. Due to population growth, expansion of the agricultural and technological sectors, and similar factors, the per capita renewable water resources in Iran have declined. According to United Nations forecasts, by the 2020s, this amount will fall below the water scarcity threshold (1000 cubic meters), plunging the country into severe water scarcity. This will widen the gap between water supply and demand, leading to economic losses, socio-political tensions, and health risks. Therefore, these combined conditions underscore that water scarcity is a central social issue (Astaneh et al., 2019: 110).
Zanjan City, the capital of Zanjan Province and one of the cities in northwestern Iran, has experienced rapid population growth and physical expansion in recent decades. This expansion has largely occurred in a dispersed, peripheral manner, primarily on lands surrounding the city. The peripheral areas of Zanjan, which were once mainly villages and agricultural lands, have now become arenas for rapid land-use changes, extensive migration, and the formation of heterogeneous urban fabrics. These areas serve as connecting rings and transitional zones between the city and the countryside and, due to multiple and often weak management, are highly vulnerable. On the other hand, Zanjan Province, and particularly the peri-urban area of Zanjan City, has increasingly faced prolonged droughts, declining rainfall, falling groundwater levels, and reduced surface water flow in recent years. This has undermined the economic and livelihood foundations of the residents in these areas.
Under such conditions, ignoring the social and human dimensions of drought-induced displacement can deepen inequalities and exacerbate social harms. Therefore, addressing this issue is critically important not only in urban and rural planning but also in broader developmental policy-making. A detailed examination of the social impacts of these displacements can help identify critical points, develop damage mitigation strategies, and enhance the resilience of local communities against environmental crises.
Accordingly, the main research question is posed as follows: What social impacts has drought-induced displacement had in the peri-urban areas of Zanjan, and which of these impacts has been more significant?

Methodology
This applied research employed a mixed (qualitative-quantitative) method and a questionnaire tool. Data were collected from two groups: 50 experts (using the Delphi method) and 334 local residents on the outskirts of Zanjan city. Data analysis utilized Delphi, one-sample t-test, and the DEMATEL model.

Results and discussion
The Delphi results indicate a strong consensus and high stability in expert opinions regarding the social impact indicators, as the negligible difference in crisp values between the two stages (between 0.004 and 0.015) confirms the content validity and reliability of the research indicator framework. Based on the one-sample t-test results, migration to the periphery of Zanjan has led to fragile and unstable economic improvements, failing to eliminate the structural vulnerability caused by drought. Conversely, this displacement has been accompanied by a deep rupture in social networks, a decline in the sense of belonging, and increased stress, creating a "vulnerability trap" that reduces the resilience of migrants and casts doubt on the sustainability of settlement in these areas.Finally, according to the DEMATEL model, "Economic Status" is the key driver (cause) of the system, exerting the most influence on other components, while "Future Outlook" is a dependent component (effect). "Social Cohesion" and "Mental Health" play crucial mediating roles. To prevent economic growth from translating into social division, interventions must simultaneously focus on economic improvement and strengthening support networks.

Conclusion
This research demonstrates that drought-induced displacement to the periphery of Zanjan is a complex process with contradictory outcomes. Although migration has slightly improved the economic conditions of some households, this improvement is superficial and unstable and has not eliminated the structural vulnerability caused by drought. In contrast, the social cost of this displacement has been substantial. The severe breakdown of traditional support networks, decreased social participation and sense of belonging, and increased stress and anxiety are among the most prominent negative impacts. This erosion of social capital has severely undermined the resilience of the migrant community against future shocks. Structural relationship analysis also confirms that economic and livelihood status plays the role of a key driver, while future prospects and sustainability are a dependent and resultant component. Therefore, short-term economic improvements cannot compensate for the loss of social cohesion and identity. Ultimately, it can be said that forced migration in this context, rather than creating a successful transition, has created a kind of "vulnerability trap" in which migrants on the urban periphery are caught in fragile conditions lacking adequate social support. This finding underscores the necessity of designing integrated policy interventions that simultaneously address sustainable livelihoods and the strengthening of social capital.

Funding
According to the responsible author, this article has no financial support

Authors’ Contribution
Authors contributed equally to the conceptualization and writing of the article. All of the authors approved thecontent of the manuscript and agreed on all aspects of the work declaration of competing interest none.

Conflict of Interest