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Exposé sur le trafic d'influence en milieu scolaire

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Par   •  8 Janvier 2020  •  Dissertation  •  2 097 Mots (9 Pages)  •  4 661 Vues

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INTRODUCTION

Controlling water supplies is a factor of conflict. Men have long been able to take advantage of water resources by settling near major rivers, lakes and shorelines. By using the rivers to move, and by creating facilities to capture the water.

In the Middle East, the regions of the Fertile Crescent from Egypt to Mesopotamia benefit from the water brought by three major rivers: the Tigris, the Euphrates and the Nile. These rivers have been the cradle of the great civilizations of the near and Middle East. In Southeast Asia, the civilization of Angkor has also developed around the control of water.

 

I - MOBILIZATION AND PROTECTION OF WATER RESOURCES

On the basis of the International Convention on the Rights of the Child, UNICEF defends the rights of the child all over the world and acts to ensure the survival and development of every child; the child has the right to enjoy the best possible state of health.

• To have access to drinking water and sanitation: build / rehabilitate wells and sanitary facilities (especially in schools for children).

• To fight against water-related diseases: -provide equipment for purifying, treating polluted water and drinking water supply; - educate households about good hygiene practices. Whether it is drinking water or water for other uses such as agriculture and energy, Africa faces a major challenge in mobilizing raw water resources. In fact, several billion cubic meters of water flow each year to the oceans because of the absence or insufficiency of suitable retention and storage structures; works whose realization is confronted with environmental issues and costs beyond the reach of local, national and continental financial resources.

With more than 60 watersheds of Transboundary Rivers, Africa will have to take into account the "conflict risk" in the sharing of these waters, both between countries, but also between uses. Similarly, the anarchic development of human settlements and the high concentration of populations on the beds of certain rivers expose them to the various discharges and pollutions of human activity, particularly in large urban centers.

Africa will therefore have to meet the challenge of mobilizing renewable water resources and their protection in the coming decades if it is to guarantee sustainable services.

1 - An abundant resource on Earth but unequally accessible

The Earth is called "the blue planet" because water covers 71% of its surface. The surface of the seas and oceans is therefore greater than that of the land masses. But fresh water only covers a small part of it. Indeed, seawater constitutes 97.5% of the world's water. Leaving only a small amount of fresh water distributed as follows:

• 70% of freshwater is held in the form of snow or glaciers on the mountains or in the ice sheets (very thick layer of ice covering a land, an island or a continent).

• 29.7% are groundwater contained in aquifers (more or less deep groundwater reserves). They are divided as follows:

. The groundwater: It is shallow and renewable, it is fed by precipitation, sources etc.

. fossil layers: They are very deep, contained in arid or semi-arid regions. Their farms deplete them and they are no-renewable.

The Earth is called "the blue planet" because water covers 71% of its surface. The surface of the seas and oceans is therefore greater than that of the land masses. But fresh water only covers a small part of it. Indeed, seawater constitutes 97.5% of the world's water. Leaving only a small amount of fresh water distributed as follows:

• 70% of freshwater is held in the form of snow or glaciers on the mountains or in the ice sheets (very thick layer of ice covering a land, an island or a continent).

• 29.7% are groundwater contained in aquifers (more or less deep groundwater reserves). They are divided as follows:

. The groundwater: It is shallow and renewable, it is fed by precipitation, sources etc.

. fossil layers: They are very deep, contained in arid or semi-arid regions. Their farms deplete them and they are non-renewable.

• 0.5% forms surface water, representing less than 1% of all fresh water on the Earth's surface. The water of lakes and rivers flows towards the seas, and thus participates in the water cycle. Men draw fresh water from groundwater, fossil aquifers, and surface water. Water is one of the main natural resources that generate life on the planet. This is why the whole society must daily pay attention to its use because the statistics are worrying.

2 - An unevenly distributed resource

Water resources are poorly distributed among countries, regions and people. Some regions are under water stress: a critical situation characterized by unavailability of water, it implies a shortage.

The cold areas are sparsely populated while they have plenty of water. On the other hand, arid regions are very populous and have only a very small amount of water.

Five countries have half of the world's water resources: Russia, China, Canada, Indonesia and the United States.

Thus, in the North the water needs are largely satisfied, the population over consumes and wastes water. While in the south 1.5 billion people do not have access to drinking water because of aridity and lack of sufficient infrastructure.

3 - Varied uses and arrangements for capturing water

Agriculture absorbs more than 70% of the water consumed in the world. The industry uses 20% and only 10% of the water is used for drinking, cooking, washing, etc. The UN estimates that each person needs 20 to 50 liters of water a day to meet their needs. Some productions are more water-hungry than others:

• 1 kilogram of apples consumes 500 liters of water.

• 1 kilogram of wheat consumes 1000 liters of water.

• 1 kilogram of hens consumes 1200 liters of water.

• 1 kilogram of milk consumes 2000 liters of water.

• 1 kilogram of sugar consumes 3000 liters of water.

• 1 kilogram of rice consumes 4000 liters of water.

• 1 kilogram of cheese consumes 5000 liters of water.

• 1 kilogram of cotton tee-shirt consumes 7000 liters of water.

• 1 kilogram of tea consumes 9000 liters of water.

• 1 kilogram of beef consumes 12,000 liters of water.

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