Building islands in open seas is not a new concept, but the scale and speed at which China has created artificial islands in the South China Sea over the past decade is unprecedented. Through massive dredging operations, submerged coral reefs have been transformed into permanent landforms, altering one of the world’s most ecologically sensitive marine regions. While these projects are often discussed in the context of geopolitics and shipping routes, their environmental consequences remain far less visible.
The Spratly Islands lie at the heart of one of the richest marine ecosystems on Earth. Over thousands of years, coral reefs here formed complex underwater landscapes that supported diverse marine life. In just a few years, dredging vessels removed sand, coral, and sediment from the seabed and deposited it onto shallow reefs, raising them above sea level. Satellite images clearly show the physical transformation, but scientists warn that the real damage lies beneath the surface.
Dredging Operations Have Permanently Altered the Seabed
Creating land in the middle of the sea requires enormous quantities of material. Dredging ships scrape sand and coral from the ocean floor, often extracting it from nearby reefs and lagoons. This material is then pumped onto submerged features until solid land emerges.
The process releases fine sediment into the water, which can drift across large distances. These suspended particles block sunlight, making it difficult for corals and seagrass to survive. When the sediment settles, it can smother living reefs, cutting off oxygen and disrupting water circulation. Marine scientists say these changes destroy reef structures that took centuries to develop.
Coral reefs are living systems, not just rocky foundations. They serve as habitats for fish, breeding grounds for larvae, and natural barriers that shape ocean currents. Once buried under sand and concrete, the organisms that build reefs die, and recovery becomes highly unlikely within any human timeframe.
Loss of Coral Reefs Threatens Marine Life and Coastal Communities
The South China Sea supports some of the highest marine biodiversity in the world, including endangered species such as sea turtles, sharks, and giant clams. Reefs in the Spratly region also act as nursery grounds for fish populations that supply fisheries across Southeast Asia. Damage to these reefs affects ecosystems far beyond the immediate construction zones.
Artificial islands also change how water moves through the region. Natural reefs influence currents and wave patterns, but solid land structures redirect water flow, leading to erosion in some areas and sediment buildup in others. These changes can damage nearby reefs that were not directly dredged and disrupt the movement of nutrients and marine larvae.
Experts say the environmental impact of large-scale reef burial is largely irreversible. Unlike oil spills or surface pollution, the physical removal of reef structures leaves little opportunity for recovery. While some artificial islands include limited environmental measures, such efforts cannot replace lost ecosystems.
From above, the reclaimed islands appear stable and orderly. Beneath the waterline, broken reefs, altered seabeds, and disrupted habitats tell a more troubling story. Scientists continue to study the long-term consequences, but access to some areas remains restricted. What is already clear is that artificial island construction in sensitive marine environments carries ecological costs that extend far beyond the visible shoreline.