Effect of Sea-Level Rise and Human Activity on the Yangtze Delta, China

The Yangtze Delta, with an area of about 40,000 km2 and a population of about 40 million, is one of the largest and most heavily populated deltas in the world. The low-lying delta includes a considerable amount of reclaimed lands with elevations less than 2 m above mean sea level. Natural rates of subsidence throughout the delta appear to be less than 5 mm/year, but locally rates have exceeded 100 mm/year where groundwater pumping has been excessive.Future sea-level rise will directly threaten the safety of the delta lowlands, particularly if subsidence accelerates in response to groundwater removal. The impact of rising sea level also may be exacerbated if water and sediment from the Yangtze River is prevented from reaching the East China Sea. A great part of the delta could be affected by salt-water intrusion, causing damage to agriculture, industry, water supply, and inland navigation.