Sand is used to make concrete and glass, it is an
essential ingredient of nearly every modern highway, airport, dam, windowpane,
and solar panel. Although desert sand is plentiful, its wind-tumbled particles
are too smooth—and therefore not cohesive enough—for construction material.
Instead, builders prize sand from quarries, coastlines, and riverbeds.
Sand is being dredged from inland
freshwater lakes, altering lake ecology; as well as literally being hauled away
by the shovel full from India’s Arabian Sea shoreline. The sand removal is resulting in the loss of
seagrasses and declines in Ganges River dolphin and terrapins, a critically
endangered turtle.
Scientists are now tracing the
collateral damage of sand removal. Sediment
plumes, stirred up by the dredging, block sunlight impeding photosynthesis of
the nearby seagrass meadows. These
meadows nourish several species, including the dugong, which is also in
decline.
Between 1994 and 2012, global cement
production—a proxy for concrete use—tripled, from 1.37 billion to 3.7 billion
tons, driven largely by Asian construction.
Land reclamation projects, too, have a rapacious hunger for sand.
Singapore, for example, has expanded its land area by 22% using sand primarily
from Malaysia, Cambodia, and Indonesia as fill. sand mining—on an industrial
scale and by individual operators—greatly exceeds natural renewal rates.
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