Impact of Land Reclamation on the Evolution of Shoreline Change and Nearshore Vegetation Distribution in Yangtze River Estuary

Abstract

Land reclamation directly changes the local coastal morphology, causing potential ecological consequences. To quantify how land reclamation influences the shoreline change, we employed shape entropy, in addition to traditional parameters, including shoreline length, land area change rate, and fractal dimension, extracted from SPOT satellite images from a number of representative years throughout two decades (1987–2012) to describe shoreline changes in Yangtze River Estuary, China. The vegetation growth boundary, representing the nearshore vegetation distribution as an ecological indicator, was also extracted and compared with the shoreline result. This comparison indicated that both vegetation growth boundary and shoreline evolve in a more complex and yet more orderly pattern partly because of land reclamation. Vegetation growth boundary changes more dramatically than shoreline, due to the combined effects of agricultural development and artificial beach nourishment, as well as the alternation of tidal creeks. These results have important implications for coastal wetland conservation and utilization in regions with intensive land reclamation such as the Yangtze River Estuary.