Assessment of Long-Term Changes in Per Capita Renewable Water Resources on the Persian Gulf Coastal Islands in Hormozgan Province

Water scarcity constrains development across the Persian Gulf islands of Hormozgan Province, Iran. We quantified per-capita renewable water resources (RWRPC) for ten islands over ۱۹۹۶-۲۰۲۳ by integrating interpolated precipitation with census-based population estimates and applying three rainfall-loss scenarios to evaporation (۶۵-۷۵%). Although mean annual rainfall (۱۰۶-۱۷۵ mm) was highly variable, no significant downward trend was detected. In contrast, population growth drove an >۸۰% decline in RWRPC, pushing all islands below the Falkenmark water-stress threshold (۵۰۰ m³ yr¹ capita¹) by ۲۰۲۳. Under the ۷۰% loss scenario, long-term average RWRPC ranged from ۱۴۵ m³ yr¹ capita¹ on Kish to ۹,۸۷۴ m³ yr ۱ capita¹ on Hendurabi; projections to ۲۰۳۶ indicate further declines to ۸۷ and ۵,۵۷۵ m³ yr ۱ capita¹, respectively. A sectoral water-use capacity assessment, assuming that at most ۴۰% of renewable water is available for human use, shows that endogenous supplies cover only a fraction of domestic demand on densely populated islands, while yielding substantially higher economic returns if prioritized for industry or high-value agriculture. These results underscore difficult allocation trade-offs and the urgency of integrated water-resources management-combining rainwater harvesting, demand-side efficiency, and renewable-energy-powered desalination to secure resilient, sustainable development pathways for these arid coastal islands.

کلیدواژه ها:

Per capita water resources ، Water scarcity ، Persian Gulf islands ، Falkenmark index ، Sustainable water management