The ganges in india and chang jiang (yangtze) in china are river valleys with concentrations of

They are both river valleys with the concentrations of rice. It supplies an everlasting source of irrigation to a large area of river valleys. There are other crops that have been cultivated there like sugarcane, oils seeds, lentils, wheat, potatoes, and most especially the main crop which is rice. Aside from that, there are also fishing opportunities down the river.