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 to US$448 billion which makes its economy about the size of Taiwan's and by 2017 this figure has increased to US$1.5 trillion ( or US$3.0 trillion in PPP), about the same size as Russia. The abundance of employment opportunities created a pool of wealthy, middle-income, professional consumers with an annual per capita income that puts them among China's wealthiest. Since the onset of China’s reform program, the Pearl River Delta Economic Zone has been the fastest growing portion of the fastest growing province in the fastest growing large economy in the world. Dongguan, Zhongshan, Nanhai, and Shunde (the later two