The greed of the mighty rivers

Read the passage carefully and answer to the questions given below:

Meherjan lives in a slum on the Sirajgonj Town Protection Embankment. Her polythene-roofed shelter looks like a cage. She is nearly 45 but looks more than her age. Infront of her shelter, she is trying to make a fire to cook the day's only meal. Her weak hands tremble as she adds some fallen leaves and straw to the fire. The whispering wind from the river Jamuna makes the fire unsteady. The dancing flames remind Meherjan of the turmoil in her life. Not long ago Meherjan had everything- a family, cultivable land and cattle. The erosion of the Jamuna gradually consumed all her landed property. It finally claimed her only shelter during the last monsoon. It took the river only a day to devour Meher's house, trees, vegetable garden and the bamboo bush. She had a happy family once. Over the years, she lost her husband and her family to diseases that cruel hunger and poverty brought to the family. Now, she is the only one left to live on with the loss and the pain. The greedy Jamuna has shattered her dreams and happiness. There are thousand others waiting to share the same fate like Meherjan. Bangladesh is a land of rivers, some of whose banks overflow or erode during monsoon. Erosion is a harsh reality for the people living along the river banks. During each monsoon many more villages are threatened by the mighty rivers like the Jamuna, the Pad.ma and the Meghna. It is estimated that river erosion makes at least 100,000 people homeless every year in Bangladesh. Infact, river erosion is one of the main dangers caused by climate change. If we can't take prompt actions to adapt to climate change, there will be thousands of more Meherjans in our towns and villages every year.

In paragraph 3, ‘mighty rivers’ mean-