What benefits did Aswan Dam bring to the Egyptian people?

Beneficial effects: 1. Dam is a comprehensive utilization project integrating flood control, irrigation, shipping and power generation. 1964 A rare flood occurred in the Nile. Because the first phase of Aswan High Dam was completed at that time, it could store water and prevent floods, which saved the Egyptian people from a disaster. Since then, the Aswan High Dam has successfully solved the threat of the Nile flood to Egypt again and again.

2. In terms of industry, the dam has 12 175 MW generators with a total power of 2 100 MW. Power generation started in 1967, and 1998 accounted for 15% of Egypt's total power generation. At the peak, it accounts for half of Egypt's total power generation and can even export electricity to neighboring countries.

3. In agriculture, dams have effectively reduced the losses caused by 1964 and 1973 floods and 1972-1973 and1984 droughts. Egypt was basically self-sufficient in food when almost all of Africa was in famine. The reservoir has also developed fisheries.

Another special advantage is that Egypt got rid of its unfriendly neighbor Sudan and had the opportunity to control the Nile water, Egypt's lifeline.

counteraction

1. The dam project led to the continuous decline of arable soil fertility in river basins. Before the dam was built, agriculture in the lower Nile benefited from the seasonal changes of the river. When the rainy season comes every year, the flooded river covers a lot of fertile sediment on the cultivated land, which periodically supplements the soil with fertility and water. However, after the completion of the dam, although water diversion irrigation can ensure that crops are not threatened by the previous drought. However, due to sediment blocking in the upstream of the reservoir area, the land in the downstream irrigation area can not be nourished. As a result, the fertility of the land is declining.

2. After the completion of the dam, soil salinization appeared on both banks of the Nile. Because the river is no longer flooded, there will not be a lot of river water to take away the salt in the soil in the rainy season. Continuous irrigation will raise the groundwater level and bring the salt in the deep soil to the surface. In addition, the irrigation water has high salt content and many chemical residues, which leads to soil salinization.

3. The water quality of the Nile in the reservoir area and downstream of the reservoir has deteriorated, which has endangered the health of residents who use this river as their living water source. After the completion of the dam, the water quality and physical properties of the reservoir are obviously worse than the original Nile water. Water evaporation in reservoir area is an important reason for water quality change. Another reason is that the decline of land fertility forces farmers to use a lot of chemical fertilizers, and the residual part of chemical fertilizers returns to the Nile with irrigation water, which increases the nitrogen and phosphorus content of the river water, leading to eutrophication of the river water and an increase in the average density of plant plankton in the downstream river water. In addition, soil salinization leads to a large increase of salt and chemical residues in the soil. Even if the groundwater is polluted, the salt content of the Nile water will also increase. These changes not only have a significant impact on the survival of organisms in the river and the irrigation of cultivated land in the basin, but also poison the drinking water of residents in the lower reaches of the Nile.

4. The change of river water nature makes aquatic plants and algae spread everywhere, which not only evaporates a lot of river water, but also blocks the river irrigation channels and so on. Due to the regulation of river flow, the turbidity of river water decreases and the water quality changes, which leads to the proliferation of aquatic plants. These aquatic plants not only spread all over irrigation channels, but also invaded major rivers. They hinder the effective operation of irrigation channels and need to be cleaned by mechanical or chemical methods frequently. This way. This also increases the maintenance cost of the irrigation system. At the same time, aquatic plants also transpiration a lot of water. According to the estimation of the Ministry of Irrigation in Egypt, the annual water loss due to transpiration of aquatic weeds reaches 40% of the irrigation water.

5. The riverbed of the lower Nile has been seriously eroded, and the coastline of the Nile estuary has retreated. The decrease of sediment in the river has led to the erosion of the riverbed in the lower Nile.