Abstract
Mega-desalination projects have become a central strategy for addressing water scarcity in arid coastal regions, yet their broader spatial and governance implications remain insufficiently examined. While prior studies have largely focused on operational impacts such as brine discharge, limited attention has been given to desalination-driven coastal land use change and its cumulative ecological and social consequences. This systematic review synthesizes global evidence on how mega-desalination projects act as drivers of coastal land transformation and assesses their impacts on marine and coastal ecosystems as well as emerging socio-environmental conflicts.
Following PRISMA guidelines, peer-reviewed articles and authoritative international reports published in this decade were systematically screened across major scientific databases. Thirty high-relevance studies were included and analyzed using an integrated framework that links land use change, ecosystem impacts, and governance dynamics. The findings indicate that mega-desalination projects often serve as spatial anchors for industrial clustering and shoreline hardening, resulting in habitat degradation, increased salinity and thermal stress, and reduced ecosystem resilience. Furthermore, governance gaps—characterized by centralized planning, limited stakeholder participation, and unequal cost–benefit distribution—emerge as key drivers of conflict between governments, local communities, and environmental systems. These insights are particularly relevant for the Persian Gulf and the Sea of Oman, where rapid desalination expansion intersects with ecological vulnerability and contested coastal governance.

EXTENDED ABSTRACT

Introduction

The accelerating deployment of large-scale seawater desalination has become a defining feature of water security strategies in arid and semi-arid coastal regions worldwide. Nowhere is this trend more pronounced than in the Persian Gulf and the Sea of Oman, where desalination supplies a dominant share of municipal and industrial freshwater demand. Despite its growing strategic importance, desalination is still predominantly conceptualized as a technical and sectoral solution to water scarcity. Such framing underestimates its role as a transformative coastal intervention that reshapes land use patterns, marine ecosystems, and governance relations simultaneously. This extended abstract synthesizes findings from a systematic review of international and Persian-language literature to examine desalination as a coupled land–sea system driver and a latent source of socio-environmental conflict.
Previous desalination research has focused primarily on near-field marine impacts, particularly brine discharge, thermal loading, and chemical additives. While these effects are well documented, they represent only one dimension of a broader transformation process. Recent studies increasingly highlight that mega-desalination plants are rarely isolated facilities; rather, they are embedded within industrialized coastal corridors that include power generation, petrochemical complexes, ports, and logistics hubs. This spatial co-location produces long-term land use change through shoreline hardening, land reclamation, exclusion zones, and altered coastal accessibility. However, the cumulative implications of these land-based transformations for marine ecosystem resilience and social conflict remain underexplored, particularly in semi-enclosed seas with limited flushing capacity such as the Persian Gulf

Methods and Analytical Framework
This study systematically reviews 30 peer-reviewed international and Persian-language publications, selected based on relevance to desalination impacts, coastal land use change, marine ecology, and governance in arid coastal settings. The analysis integrates empirical field studies, remote sensing assessments, oceanographic modelling, life-cycle analyses, and governance-oriented research. Findings are synthesized using a socio-ecological systems framework that links technological scale, spatial planning, ecological stress pathways, and institutional capacity. The Persian Gulf and the Sea of Oman are treated as focal case regions due to their extreme baseline conditions—high temperature, salinity, and evaporation rates—and their unparalleled density of desalination infrastructure.

Results and discussion
Desalination as a Driver of Coastal Land Use Transformation: Across the reviewed literature, desalination facilities consistently emerge as anchoring infrastructure that catalyses durable coastal land use reconfiguration. Studies show that plant siting decisions often prioritize proximity to energy supply, deep-water access, and industrial zones, reinforcing patterns of coastal industrial clustering. These processes convert previously multifunctional or ecologically sensitive shorelines into permanently industrialized landscapes. Remote sensing and GIS-based studies from the southern Iranian coast and Arabian Peninsula confirm accelerated shoreline modification, land reclamation, and loss of natural coastal buffers in proximity to desalination and associated infrastructure. Such spatial transformations generate path dependency, constraining future coastal management options and locking regions into high-impact development trajectories.
Ecological Impacts Beyond Brine Discharge: While brine discharge remains a central concern, the reviewed evidence demonstrates that ecological degradation linked to desalination arises through interacting stress pathways rather than single mechanisms. Field studies in the Persian Gulf document localized increases in salinity, temperature, and heavy metal concentrations in sediments near outfalls, accompanied by declines in microbenthic diversity and shifts in community composition. Modelling studies indicate that although basin-scale salinity increases may appear modest, near-field impacts frequently exceed ecological tolerance thresholds, particularly in shallow coastal environments. Importantly, land use change associated with desalination—such as shoreline armouring and habitat removal—reduces ecosystem resilience by eliminating natural buffers, seagrass meadows, mangroves, and tidal flats that would otherwise mitigate cumulative stress. In semi-enclosed systems, these spatial effects amplify the ecological footprint of desalination far beyond discharge zones.

Governance and the Emergence of Socio-Environmental Conflict: A key finding of this review is that environmental degradation does not automatically translate into overt conflict; rather, conflict emergence is mediated by governance structures. Desalination-intensive regions, particularly in the Persian Gulf, are characterized by centralized decision-making, sectoral fragmentation, and limited stakeholder participation. Environmental impact assessments are typically conducted at the project scale, failing to capture cumulative land–sea interactions and long-term coastal transformation [3]. As a result, coastal communities often experience restricted access to shorelines, declining fisheries, and degraded marine environments, while the primary benefits of desalinated water are transferred to distant urban or industrial users. This distributional asymmetry reframes environmental impacts as issues of procedural justice and legitimacy, creating conditions for latent and persistent socio-environmental conflict even in politically stable contexts.
An Integrated Conceptual Model: Synthesizing these findings, the study proposes an integrated conceptual model in which desalination-driven coastal conflict emerges from misalignments among four interdependent components: (1) technological and spatial drivers, including plant scale and industrial co-location; (2) ecological stress pathways, encompassing cumulative impacts on marine and coastal ecosystems; (3) governance filters, such as regulatory coherence, institutional coordination, and transboundary arrangements; and (4) social and distributional dynamics that shape how costs and benefits are perceived and allocated. Conflict is thus understood as structural and systemic, rather than episodic or project-specific.
Implications for the Persian Gulf and Comparable Regions: The Persian Gulf and the Sea of Oman exemplify regions where rapid desalination expansion coincides with ecological fragility, accelerating coastal industrialization, and evolving socio-political dynamics. Without integrated coastal zone management, strategic environmental assessment, and regional coordination, continued reliance on mega-desalination risks pushing already stressed marine ecosystems beyond critical thresholds. The findings underscore the need to reconceptualize desalination as a coastal land use intervention with systemic socio-ecological consequences, rather than a neutral technological solution to water scarcity.

Conclusion
This extended abstract demonstrates that the sustainability challenges associated with desalination are fundamentally spatial, ecological, and institutional in nature. Addressing them requires moving beyond project-based mitigation toward cumulative, conflict-sensitive, and ecosystem-informed planning frameworks. Such a shift is essential for ensuring the long-term environmental integrity and social legitimacy of desalination-driven water security strategies in the Persian Gulf, the Sea of Oman, and analogous arid coastal regions.