Environmental problem

Good morning every body,

My presentation today is about the environmental problem. This problem comes from our impacts on the water cycle. There are four different types of impacts: changes to earth’s surface, changes to earth’s climate, air pollution and withdrawals for human use. I am going to talk about two first impacts.

Firstly, the route of the water cycle changes as human cut down tree and overuse the land. Water stops filtering through the ground. Instead, water runs straight into the streams or rivers. This may not only cause floods, but also erode the land it flows over. This cause damage, and also bring more sediment   nuhu and other pollution into the rivers. Events in Bangladesh give us a good example. That country is very flat. Most of the land is only a few meters above sea level. They get a lot of floods in recent years and it likely to get worse. Extreme flooding is now common there. When people travel hundreds and sometimes thousands of kilometers up the river to India and Nepal, they found that many trees were cut down from the lower parts of the Hymalayan mountains. This has caused erosion, and the eroded material, the sediment, has washed down the river. Because of this, the Ganges River basin has risen between five and seven meters in recant years! A flood in 1998 covered 60% of the country and caused nearly a 1000 deaths.

Secondly, when water just quickly runs off the ground rather than soaking through it or being taken up by trees, there is less water left to evaporate and cause local rainfall. Soon, spring will dry up as the supply to the groundwater reservoirs that feed them reduces. Dry and lifeless streams are common in areas with few trees. This has terrible results for both the ecosystems and the humans who depend on the flow.

In conclusion, several of the environmental problems we face at the moment come from our impacts on the water cycle. Changes in earth’s surface and changes in earth’s climate are two among of four impacts on the water cycle. People should think and do something immediately to protect our planet.

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