Context:
Six billion tonnes of annual sand extraction from the world’s ocean floors is causing irreversible harm to marine benthic life, as revealed by a new global data platform on marine sediment extraction.
About Marine Sand
- Marine sand (or ocean sand) is a granular particle composed of silica, rock fragments and mineral particles.
Dredging:
- Dredging is the removal of sediments and debris from the bottom of lakes, rivers, harbors, and other water bodies.
- It is a routine necessity in waterways around the world because sedimentation—the natural process of sand and silt washing downstream—gradually fills channels and harbors
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Key Findings of Marine Sand Watch Platform:
- Developed by: GRID-Geneva, a Centre for Analytics within the UN Environment Programme (UNEP).Estimation of Sand Dredging: Between four and eight billion tonnes of sand are being dredeged from the ocean floor every year.
- Sand Turbidity: The extraction of sand increases the turbidity of water.
- It changes nutrient availability and causes noise pollution, thus affecting marine organisms greatly.
Benthic organisms:
- Benthic organisms live on or just beneath the bottom of the lagoon or in the intertidal zone (mainly mudflats).
- For Example: Sea anemones, Sponges
- They are important links in the estuarine food chains, providing an important food source for fishes, birds, and mammals.
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- Impact on Living Organism: Not just benthic organisms, people living in coastal communities will also be severely affected by this magnitude of sand dredging. Salinisation of Aquifers: Coastal or near-shore extraction can affect the salinisation of aquifers and future tourist development.
- Ban on Marine Sand Export: Some countries — including Indonesia, Thailand, Malaysia, Vietnam, and Cambodia — have banned marine sand export in the last 20 years.
News Source: Down to Earth
6 Sep 2023
