Question

crop cultivation supported by ganga river

Answer 1

The Ganges and its all tributaries, especially the Yamuna, have been used for irrigation since ancient times. Dams and canals were common in gangetic plain by fourth century BCE. The Ganges-Brahmaputra-Meghna basin has a huge hydroelectric potential, on the order of 200,000 to 250,000 megawatts, nearly half of which could be easily harnessed. As of 1999, India tapped about 12% of the hydroelectric potential of the Ganges and just 1% of the vast potential of the Brahmaputra.

Answer 2

In case one decides to farm on banks of the river then Any crop that could survive occasional flooding and total submerging under water during high tides. One example is Rice it can survive such conditions also some varieties of rice can tolerant some level of salinity.