Major impacts of sea-level rise on agriculture in the Yangtze delta area around Shanghai

Abstract

The projected rise in sea level for the next century will have profound impacts on peri-urban agricultural production in the Yangtze delta area. This paper assesses the major impacts of the rise in sea level on coastal processes, flood hazards and saline water incursion in relation to sustainable development of peri-urban agriculture in the deltaic plain around Shanghai, People's Republic of China. It is concluded that the rise in sea level will cause coastal erosion along the southern coast and slow sedimentary accretion in a number of shoals within the Yangtze estuary. This change will severely limit the extent of intertidal flats available for land reclamation. The rise in sea level will also increase flood risk, raise the groundwater table and prolong waterlogging. Consequently, agricultural yields will be seriously reduced. During dry seasons, saline water will dominate the deltaic area for much longer periods and shortages of freshwater for agriculture are expected to be more pronounced. Four counter-measures have been adopted by the Shanghai Municipal Government in an attempt to mitigate the effects of sea-level rise.