CyberDodo and ground water tables (1-53)
Two types of ground water tables can be identified, those that are refilled when it rains and those that were filled a very long time ago and are not renewed.
1. Renewable water tables
As indicated on the first page, they are at risk, and not just due to pollution. Another major danger is the increasing pumping of water, which uses up most of it. As the population does not stop growing, and it has its needs, the unceasing collection of water does not even allow the water tables to fill, with the risk of drying out.
Not forgetting another danger linked to the reduced volume, the waters coming from the surface are increasingly polluted, they proportionally contaminate the reservoir more easily and can make the ground water table unfit for human consumption.
Finally, agriculture is also a threat at two levels. This has to do with exponential irrigation needs which make pumping multiply but also the use of a multitude of chemical products (like pesticides) which rain water will carry into underground reservoirs.
2. Fossile water
The situation of water tables referred to as ‘fossiles’ is even more serious, as they are faced with all the problems mentioned above, as well as the fact that they are not filled again.
Each litre that is drawn is one litre less!
Countries which should find alternatives more or less soon for their fresh water supply are situated in various parts of the globe, such as Australia or Siberia, the Arabic peninsula or even the centre of the United States.
What does the future hold for us?
It is indeed impossible to foresee with certainty what is going to happen in the decades to come, however, some serious trends are emerging, linked notably to overpopulation, pollution and global warming.
Numerous experts fear that conflicts may break out between neighbouring countries for the control of water, a situation which has more or less tended to take place in the Near East. But Asia, South America and Africa are not immune to tensions between the states in relation to fresh water supply.
Agriculture is another major issue, because it is no longer possible to ‘grow whatever you want wherever you want’ by using chemical fertilisers on the one hand and on the other hand removing cubic metres upon cubic metres of water from ground water tables which are increasingly under pressure. Only rational agriculture using plants adapted to local climatic conditions is compatible with the sustainable management of water resources.
With regard to global warming, it represents a global challenge, its impact on fresh water reserves can become one of the main threats to the survival of the human species.
Examples: rainful in certain regions could reduce dramatically, bringing in a reduction of volume of water courses, lakes and ground water tables, with the terrible consequences that one can anticipate; sea levels could rise and contaminate numerous ground water tables, making them unfit for human consumption.
It is therefore fundamental to preserve fresh water as of today, for future generations, but also for us!
To see the cartoon on water resources, click here
For the quiz, click here
© CyberDodo Productions Ltd
As we saw in the case file on water, 70% of our planet is covered in water, which could lead us to believe that it is a renewable resource. Everything changes when you look at the situation from the point of view of a human being who needs fresh water to survive …
Because the figures are no longer the same at all; out of 100 drops of water that fall on earth, 97 are salty, therefore they can not be consumed directly by humans - there are only 3 drops of fresh water, but 2 out of these 3 drops are in an iced state.
Human beings can therefore only rely on 1 drop of water out of 100, and this is without even subtracting anything, because 65 % of this meagre resource is taken up by irrigation of crops and another 20% by industry!
Do you understand our title better: “Fresh water is very precious”? In this context where accessible fresh water is very rare, ground water tables become as precious as hidden treasure … however, what is a ground water table?
It is a reservoir created by nature which holds water. This reservoir consists of a floor that has a waterproof bed which stops water from penetrating beneath it.
Why are ground water tables so important?
We have already seen that a little more than a tenth of a drop of fresh water (out of 100) is availabe for direct consumption by man, which is very little. Pay attention, because this phrase will explain the issues at stake in this case file: 95% of this rare resource is stored in ground water tables. In other words, the future of man depends on the water contained in these natural reservoirs because they provide a half to a quarter of our water for consumption, depending on the countries.
But the ever increasing encroachment of the human species, as well as pollution, are a serious threat to the environment.
To understand this, let’s imagine that we are out in the wild, man has not yet ravaged the earth and it is raining. After being soaked up by the vegetation and drunk by the animals, the remaining water slowly inflitrates the soil, penetrating the mineral beds as it gradually flows through the different geological strata. In one phase, it encounters a waterproof bed, such as clay, and will accumulate in order to set up a ground water table.
When the surface soil is filled with water, it will flow until it joins rivulets, rivers, dams, etc…which in turn flow into lakes and seas. Later, this water evaporates, forming clouds that will give rain, etc.
A perpetual cycle, in fact, until man became involved, and because of his obsession with turning everything into concrete, water from towns no longer directly infiltrates the earth, but is collected and then goes to water purification stations where it comes into contact with pollutants which shall be more or less properly processed before the water is rejected to nature.
At the worst, after having washed through the roads and drains that are filled up with all types of garbage, the water then reaches the ground water tables, which it will pollute.
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