There are many causes related to the depletion of rain forests. One would be fires. Another would be trees being cut down almost every year. The main destruction cause would be us humans.
A possible solution for stopping the depletion of rain forests would most probably be to make sure that the animals, plants, and the rain forest itself is healthy. If it is not, there may be serious trouble. Another solution would probably be for us humans to leave the rain forests alone. Alot of fires are caused by us, and chopping down the trees of the rain forest kills the animals, plants, and of course the trees in that rain forest, causing the rain forest to eventually deplete.
Because of Dhaka's position below sea level the city experiences yearly flooding, particularly around the monsoon seasons and has the constant threat of rising sea levels, which would of course cause more flooding.
