River delta slope offshore, waves will make river deltas smoother. Waves can also be responsible for carrying sediments away from the river delta, causing the delta to retreat. For deltas that form further upriver in an estuary, there are complex yet quantifiable linkages between winds, tides, river discharge, and delta water levels. Erosion is also an important control in tide-dominated deltas, such as the Ganges Delta, which may be mainly submarine, with prominent sandbars and ridges. This tends to produce a "dendritic" structure. Tidal deltas behave differently from a river- and wave-dominated deltas, which tend to have a few main distributaries. Once
Pearl River Delta Economic Zone reforms, and stock market development. The economic development of the Pearl River Delta Economic Zone took off after the reform programme was instituted. The region's GDP grew from just over US$8 billion in 1980 to more than US$89 billion in 2000 and nearly US$221.2 billion in 2005. During that period, the average real rate of GDP growth in the Pearl River Delta Economic Zone exceeded 16 percent, well above the People's Republic of China national figure of 9.8 percent. Since the onset of China's reform programme, the Pearl River Delta Economic Zone has been the fastest growing portion of the