In many coastal arid and semi-arid regions, intensive groundwater abstraction to support tourism and agriculture has exacerbated water insecurity.
Which of the following correctly describes the process of saline intrusion in coastal aquifers and its classification as a contributor to water insecurity?
It is a physical degradation of water quality, where human-driven over-extraction lowers the hydrostatic pressure of the freshwater lens, allowing denser saltwater to migrate inland.
It is an economic water scarcity issue, where high salt concentration increases the cost of municipal filtration, rendering otherwise abundant freshwater physically inaccessible to low-income populations.
It is a natural physical cause of water insecurity, driven solely by rising sea levels that breach coastal sand dunes and flood unconfined aquifers from above.
It is a soft-engineering management failure, where excessive artificial recharge using treated wastewater elevates the water table and mobilises deep geogenic saline deposits.
