Sand in the ocean ecosystem. The marine and coastal environment is both a sink for sand delivered from rivers and an active source of sand, continuously subject to erosional and depositional processes, longshore currents, tides, waves and bio-erosion. Naturally-occurring sand acts as both a connector and a buffer at the land-sea interface, functionally linking the marine and terrestrial ecosystems while protecting the land and stabilizing the coastline in what is generally considered one of the most costeffective climate mitigation strategies to enhance coastal resilience. It underpins island morphology, shapes the seabed, controls coastal erosion, offers essential nutrients and maintains biodiversity through the formation of sand bars, beaches, dunes and other coastal landforms that support highly specialized biotic assemblages and provide habitat for a wide variety of species.
Environmental impacts. By their very nature, dredging and coastal sand mining practices imply the relocation of large volumes of earth, resulting in critical habitat destruction, loss of biodiversity, sediment suspension, and changes in the bathymetry and topography of the seabed. This causes direct loss of organisms and disrupts entire food webs, leading to a decline in ecosystem functions and services, and a long-term loss of resilience to other stressors. Sand extraction is also a major driver of coastal erosion, accelerating the loss of protective features such as beaches, dunes and sandbars. This increases the vulnerability of the shoreline to floods and storm surges (including salinization of coastal aquifers) and puts at risk the integrity of coastal infrastructure and assets. Other widespread ecological impacts include noise and chemical pollution, transfer of invasive species, and greenhouse gas emissions. In some cases, it can take up to several decades to recover from damages to the ecosystem whereas other changes are irreversible.
Cite this report as: Jouffray J-B, Barbour FP, Blasiak R, Feine J, Gallagher L, Johansson D, Kuiper JJ, Pereira K, Rawat A, Schmitt RJP, Tokunaga K, Wabnitz CCC, Norström AV (2023) Ocean sand: Putting sand on the ocean sustainability agenda. Ocean Risk and Resilience Action Alliance (ORRAA) Report
https://oceanrisk.earth/wp-content/uploads/2023/05/ORRAA_Ocean_Sand_report.pdf